WorldWideScience

Sample records for circadian intraocular pressure

  1. Circadian intraocular pressure rhythm is generated by clock genes.

    Science.gov (United States)

    Maeda, Ari; Tsujiya, Sosuke; Higashide, Tomomi; Toida, Kazunori; Todo, Takeshi; Ueyama, Tomoko; Okamura, Hitoshi; Sugiyama, Kazuhisa

    2006-09-01

    The present study in a mouse model was undertaken to reveal the role of the circadian clock genes Cry1 and Cry2 in generation of 24-hour intraocular pressure (IOP) rhythm. IOP was measured at eight time points daily (circadian time [CT] 0, 3, 6, 9, 12, 15, 18, and 21 hours), using a microneedle method in four groups of C57BL/6J mice (groups 1 and 3, wild-type; groups 2 and 4, Cry-deficient [Cry1-/-Cry2-/-]). During the IOP measurements, mice in groups 1 and 2 were maintained in a 12-hour light-dark cycle (LD), whereas mice in groups 3 and 4 were kept in a constant darkness (DD) that started 24 to 48 hours before the measurements. Circadian IOP variations in each group were evaluated by one-way analysis of variance (ANOVA) and Scheffé tests. In wild-type mice living in LD conditions, pressures measured in the light phase were significantly lower than those in the dark phase. This daily rhythm was maintained under DD conditions with low pressure in the subjective day and high pressure in the subjective night. In contrast, Cry-deficient mice did not show significant circadian changes in IOP, regardless of environmental light conditions. These findings demonstrate that clock oscillatory mechanisms requiring the activity of core clock genes are essential for the generation of a circadian rhythm of intraocular pressure.

  2. Circadian rhythm of intraocular pressure in the rat.

    Science.gov (United States)

    Moore, C G; Johnson, E C; Morrison, J C

    1996-02-01

    To define the characteristics of the diurnal variation of intraocular pressure (IOP) in eyes of awake rats, ten male brown Norway rats were entrained to a 12-hour light:12-hour dark (12L:12D) lighting schedule and were conditioned to IOP measurement with the TonoPen XL tonometer while awake, using only 0.5% proparacaine HCl anesthesia. The IOP measurements were performed in 4 experiments: Preliminary-IOP was measured at 6-hour intervals in both eyes of each animal, to determine correlation between right and left eyes; Light:Dark-lighting remained the same as in the preliminary experiment, but the measurement schedule was altered so that measurements were obtained at 4-hour intervals in alternating eyes, over two 24-hour light cycles; Dark:Dark-animals were placed in constant dark (0L:24D) and, after 72 h, measurements were obtained at 4-hour intervals in alternating eyes. Animals were then re-entrained to the previous 12L:12D schedule for 7 days, after which they were returned to constant dark and the experiment was repeated; and Dark:Light-animals were entrained to a reversed light:dark cycle (12D:12L) for 28 days, after which measurements were obtained in the same fashion as in the Light:Dark experiment. Close agreement was found between right- and left-eye IOPs. Animals on a 12L:12D schedule exhibited lowest IOP while the lights were on (19.3 +/- 1.9 mm Hg), and highest (31.3 +/- 1.3 mm Hg) while the lights were off. Pressure changes anticipated the change from light to dark and dark to light. This pattern persisted in constant dark, and was reversed when the cycle was changed to 12D:12L. Brown Norway rats possess a regular rhythm of IOP that is entrained by the cycle of light and dark, and persistence of this rhythm in constant dark establishes it as a circadian rhythm. Furthermore, our results indicate that reliable and physiologically meaningful IOP measurements can be obtained in awake rats using the TonoPen XL tonometer.

  3. Circadian Intraocular Pressure Fluctuation and Disease Progression in Primary Angle Closure Glaucoma.

    Science.gov (United States)

    Tan, Shaoying; Yu, Marco; Baig, Nafees; Chan, Poemen Pui-man; Tang, Fang Yao; Tham, Clement C

    2015-07-01

    To document the continuous circadian intraocular pressure (IOP) fluctuation using a contact lens sensor during normal daily activities, and to study the relationship between IOP fluctuation and disease progression in primary angle closure glaucoma (PACG) eyes. Circadian IOP fluctuations were recorded by Sensimed Triggerfish sensors in 25 PACG eyes. The sensor output signals were smoothed using B-spline smoothing transform and described by functional data analysis. Glaucoma progression was documented with serial changes in mean deviation (MD) and visual field index (VFI) in Humphrey automated perimetry and retinal nerve fiber layer (RNFL) thickness. The signals were compared between the progressive and stable groups by permutation tests on functional t-statistic. Statistically significant differences were found from 2200 to 2300 and from 0700 to 0800 in gradients of the IOP fluctuation curve, as well as from 2300 to 2400 and 0800 to 0900 in curvatures of the IOP fluctuation curves, between the progressive MD and stable MD groups (P < 0.05). Significant gradient differences were also found from 1500 to 1600 and 0600 to 0800 between the progressive VFI and stable VFI groups, and from 2400 to 0100 and 0200 to 0300 between the progressive RNFL and stable RNFL groups (P < 0.05). Significant differences in circadian IOP fluctuation between progressive and stable PACG eyes were identified. Large IOP fluctuations may be associated with disease progression in PACG eyes.

  4. Circadian Intraocular Pressure Fluctuation and Disease Progression in Primary Angle Closure Glaucoma

    National Research Council Canada - National Science Library

    Tan, Shaoying; Yu, Marco; Baig, Nafees; Chan, Poemen Pui-man; Tang, Fang Yao; Tham, Clement C

    2015-01-01

    .... Circadian IOP fluctuations were recorded by Sensimed Triggerfish sensors in 25 PACG eyes. The sensor output signals were smoothed using B-spline smoothing transform and described by functional data analysis...

  5. Circadian intraocular pressure patterns in healthy subjects, primary open angle and normal tension glaucoma patients with a contact lens sensor.

    Science.gov (United States)

    Agnifili, Luca; Mastropasqua, Rodolfo; Frezzotti, Paolo; Fasanella, Vincenzo; Motolese, Ilaria; Pedrotti, Emilio; Di Iorio, Angelo; Mattei, Peter A; Motolese, Eduardo; Mastropasqua, Leonardo

    2015-02-01

    To examine the circadian intraocular pressure (IOP) patterns in healthy subjects, in primary open angle and normal tension glaucoma (POAG; NTG) using a contact lens sensor (CLS; Sensimed Triggerfish, Lausanne, Switzerland). This was an observational, nonrandomized study. Ten healthy subjects (Group 1, 10 eyes) and 20 glaucomatous patients [20 eyes, 10 with POAG (Group 2) and 10 with NTG (Group 3)] were enrolled. All patients were controlled with prostaglandin analogues. The 24-hr IOP pattern was the main outcome. The morning (6AM-11AM), afternoon/evening (noon-11PM) and night (midnight-5AM) subperiod patterns, peaks and prolonged peaks (>1 hr) were secondary outcomes. Mean 24-hr IOP pattern showed a nocturnal acrophase in all groups. Patterns were significantly different among groups (p = 0.02), with highest nocturnal IOP values in POAG. Prolonged peaks were more common in patients with glaucoma (70%) than in healthy subjects (33.3%) (p < 0.001). Significant differences were found for Groups 2 and 3 in the morning versus afternoon/evening (p = 0.019 and p = 0.035, Bonferroni correction), morning versus night (p = 0.005 and p < 0.0001) and afternoon/evening versus night periods comparisons (p < 0.0001 for both groups). In Group 1, patterns significantly differed in the morning versus night and afternoon/evening versus night period comparisons (p < 0.0001). Continuous 24-hr IOP monitoring with the CLS revealed a nocturnal acrophase in healthy subjects and, more markedly, in glaucoma. Because the diurnal IOP profile seems not to predict the nocturnal rhythm, the circadian IOP pattern should be evaluated in clinical practice. These findings may be worthwhile for the management of glaucoma. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  6. Picos de pressão intra-ocular: comparação entre curva tensional diária, minicurva e medida da pressão intra-ocular às 6 horas Intraocular pressure peaks: comparison between the circadian curve, diurnal curve and the 6 a.m. measurement

    Directory of Open Access Journals (Sweden)

    Luciana Duarte Rodrigues

    2004-02-01

    ária e da minicurva.INTRODUCTION: Intraocular pressure (IOP is a major risk factor for the development of open angle glaucoma (OAG. Intraocular pressure control is the main target of glaucoma therapy at the moment. The 24-hour intraocular pressure curve (circadian curve-CC is of great importance for open angle glau-coma diagnosis and follow-up. Because of practical facilities, simplified methods such as the diurnal curve (DC have been used. PURPOSE: Comparison between circadian curve and diurnal curve as regards intraocular pressure peak detection and the verification of the influence of postural variation on 6 a.m. measurement. METHODS: Sixty-four open angle glaucoma or suspected glaucoma patients (126 eyes were submitted to circadian curve. Diurnal curves considered 9 a.m. - noon - 3 p.m. 6 p.m. measurements of the circadian curve. At 6 a.m., measurements were performed in the dark, while patients were lying, with the Perkins tonometer. Then, another measurement was taken, with the Goldmann tonometer with the patients seated. Mean intraocular pressure and intraocular pressure peaks in the circadian and diurnal curves were compared, as well as the time when the peaks occurred. RESULTS: Mean IOP was higher in the open angle glaucoma patients in both the circadian curve and diurnal curve. When the circadian curve and diurnal curve were compared, mean intraocular pressure was higher in the 6 a.m. circadian curve IOP measurement was higher when taken in bed. The diurnal curve did not detect 60.42% of the peaks in open angle glaucoma patients and 88.24% of the peaks in suspected glaucoma patients. CONCLUSIONS: 1. The circadian curve detects more intraocular pressure peaks than the diurnal curve; 2. Six a.m. intraocular pressure is higher when taken in bed; 3. 6 a.m. intraocular pressure in bed is higher than the mean intraocular pressure in both circadian curve and diurnal curve.

  7. PATTERN OF INTRAOCULAR PRESSURE IN

    African Journals Online (AJOL)

    manoeuver, forced blinking, intraocular inflammation, ocular trauma, ocular surgery, retinal or choroidal detachment, restriction, arid systemic diseases such as diabetes mellitus and thyroid disorders.“ Procedures such as retrobulbar anaesthesia, general anaesthesia, external pressure on the eyeball, topical eye drops ...

  8. Associations with intraocular pressure across Europe

    DEFF Research Database (Denmark)

    Khawaja, Anthony P; Springelkamp, Henriët; Creuzot-Garcher, Catherine

    2016-01-01

    Raised intraocular pressure (IOP) is the most important risk factor for developing glaucoma, the second commonest cause of blindness globally. Understanding associations with IOP and variations in IOP between countries may teach us about mechanisms underlying glaucoma. We examined cross...

  9. Sleeping posture and intraocular pressure.

    Science.gov (United States)

    Wong, Melissa Hsing Yi; Lai, Annie Hiu On; Singh, Mandeep; Chew, Paul Tec Kuan

    2013-03-01

    This prospective observational case series aimed to determine whether the lateral decubitus position, which is commonly adopted during sleep, has an effect on intraocular pressure (IOP) in normal controls. Patients without glaucoma were recruited from those visiting outpatient clinics for non-glaucomatous conditions. The left eye of each patient was included. IOP was first measured using Tono-Pen® XL applanation tonometer in the supine position, following which a second measurement was immediately obtained for the left lateral head position. Measurements were obtained with the patient lying on one soft and one hard pillow for each position, and patients remained awake during these measurements. One tonometry reading was obtained for each position. Readings were recorded only when the average of four independent readings produced a statistical confidence index of 5%. Results were analysed using the paired Student's t-test for comparison of the means. IOP in the left lateral decubitus position (17.48 ± 3.18 mmHg) was significantly higher than in the supine position (14.48 ± 3.09 mmHg) when using soft pillows (p IOP in the left lateral decubitus position also exceeded that measured in the supine position (16.65 ± 3.54 mmHg vs. 13.65 ± 3.58 mmHg; p IOPs measured for the same position when different kinds of pillows were used. The lateral decubitus position adopted during sleep is associated with changes in IOP in healthy volunteers.

  10. Digital palpation of intraocular pressure.

    Science.gov (United States)

    Birnbach, C D; Leen, M M

    1998-09-01

    Previous studies investigating the accuracy of digital palpation through the eyelids to estimate intraocular pressure (IOP) have shown disappointing results. In this study, the accuracy of digital assessment of IOP by palpation of the bare cornea is investigated. The IOP of a cadaveric eye model was varied from 5 to 40 mm Hg in increments of 5 mm Hg. Two examiners, one experienced and one inexperienced, digitally palpated the corneas and estimated IOP. The results were compared before and after a 1-hour training session. Prior to the training session, the experienced examiner guessed correctly 46% of the time and was correct within 5 mm Hg 100% of the time. The inexperienced examiner guessed correctly 21% of the time and was within 5 mm Hg 62% of the time. After the training session, the experienced examiner's score did not significantly (38% correct, 88% within 5 mm Hg, P = .05. Digital assessment of IOP by palpation of bare cornea is accurate when performed by experienced individuals. A minimal amount of training using the eye model may improve one's accuracy.

  11. Anterior ischaemic optic neuropathy and intraocular pressure.

    OpenAIRE

    Katz, B; Weinreb, R N; Wheeler, D T; Klauber, M R

    1990-01-01

    Anterior ischaemic optic neuropathy is a stroke syndrome of the distal optic nerve, characterised by disc oedema and optic nerve dysfunction--loss of central vision, loss of colour vision, a relative afferent pupillary defect, and nerve fibre layer field loss. We prospectively evaluated the changes of intraocular pressure throughout the day in 16 patients with non-arteritic anterior ischaemic optic neuropathy and 15 normal control subjects of similar age and race. The peak intraocular pressur...

  12. Attempted eyelid closure affects intraocular pressure measurement.

    Science.gov (United States)

    Gandhi, P D; Gürses-Ozden, R; Liebmann, J M; Ritch, R

    2001-04-01

    To evaluate the effect of attempted eyelid closure on intraocular pressure measurement. Normal subjects underwent intraocular pressure measurement in both eyes using Goldmann applanation tonometry and Tono-pen XL (Mentor, Inc, Norwell, Massachusetts) by the same examiner holding the eyelids open, both with and without the subject simultaneously attempting forced eyelid closure. Subjects were seated during all measurements and waited 5 minutes between measurements with each instrument; the order of measurement was randomized. Thirty eyes of 15 subjects (six men, nine women) were enrolled. Mean age was 30.5 +/- 5.2 years (range, 24 to 40 years). With Goldmann applanation tonometry, intraocular pressure increased in both eyes with attempted eyelid closure by a mean of 1.5 +/- 2.0 mm Hg (P =.0002, paired t test; range, -2 to 8 mm Hg). With the Tono-pen XL, intraocular pressure also increased in both eyes with attempted eyelid closure by a mean of 1.9 +/- 2.7 mm Hg (P =.0002, paired t test; range, -2 to 9 mm Hg). Tono-pen XL mean intraocular pressure values in both eyes (14.4 +/- 2.3 mm Hg) consistently overestimated those of Goldmann applanation tonometry (13.0 +/- 2.2 mm Hg) by a mean of 1.4 +/- 2.3 mm Hg. Attempted forced eyelid closure is a common and statistically significant source of error in routine outpatient measurement of intraocular pressure and could influence clinical management of glaucoma.

  13. 24-hour intraocular pressure and ocular perfusion pressure in glaucoma.

    Science.gov (United States)

    Quaranta, Luciano; Katsanos, Andreas; Russo, Andrea; Riva, Ivano

    2013-01-01

    This review analyzes the currently available literature on circadian rhythms of intraocular pressure (IOP), blood pressure, and calculated ocular perfusion pressure (OPP) in patients with open-angle glaucoma. Although adequately powered, prospective trials are not available. The existing evidence suggests that high 24-hour IOP and OPP fluctuations can have detrimental effects in eyes with glaucoma. The currently emerging continuous IOP monitoring technologies may soon offer important contributions to the study of IOP rhythms. Once telemetric technologies become validated and widely available for clinical use, they may provide an important tool towards a better understanding of long- and short-term IOP fluctuations during a patient's daily routine. Important issues that need to be investigated further include the identification of appropriate surrogate measures of IOP and OPP fluctuation for patients unable to undergo 24-hour measurements, the determination of formulae that best describe the relationship between systemic blood pressure and IOP with OPP, and the exact clinical relevance of IOP and OPP fluctuation in individual patients. Despite the unanswered questions, a significant body of literature suggests that OPP assessment may be clinically relevant in a significant number of glaucoma patients. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Pathophysiology of glaucoma and continuous measurements of intraocular pressure.

    Science.gov (United States)

    Sit, Arthur J; Liu, John H K

    2009-03-01

    Glaucoma is a leading cause of visual impairment and blindness worldwide. The main risk factor for glaucoma is an elevated intraocular pressure (IOP), which is also the only currently treatable risk factor. Despite its importance, our understanding of IOP is incomplete and our ability to measure IOP is limited. IOP is known to undergo both random fluctuations as well as variations following a circadian pattern. In humans, IOP is highest at night and lower during the daytime, largely due to changes in body position, although other factors appear to contribute. In rabbits, IOP is also highest at night and lower during the day, likely due to circadian variations in sympathetic nervous system activity. Random and circadian IOP variations may be important to glaucoma pathogenesis, independent of the diurnal IOP level. However, due to limitations with current IOP measurement technology, clinical practice typically involves only a few IOP measurements per year. As well, current technology does not allow 24-hour monitoring of pressure without the use of sleep laboratories or hospital admission. Two strategies for automating IOP measurement are temporary (non-invasive) monitoring and permanent (implantable) monitoring. Efforts at developing devices to allow continuous IOP monitoring have occurred for over 40 years without producing a clinical device. Current technological progress would seem to suggest that such devices are possible at this time, and a review of previous attempts provides guidelines for their development.

  15. Intraocular Pressure in Pregnant and Non-Pregnant Nigerian Women

    African Journals Online (AJOL)

    Erah

    A number of hormones are known to affect intraocular pressure. Of these, the female sex hormones are the predominant ones to cause variations in intraocular pressure. The aim of this study was to determine if variation in sex hormones in pregnancy affects intraocular pressure. This study was a longitudinal one.

  16. [Research progress in intraocular pressure monitoring of glaucoma].

    Science.gov (United States)

    Hao, Jie; Zhen, Yi; Ma, Jian-min; Wang, Ning-li

    2013-09-01

    Elevation of intraocular pressure (IOP) is a major risk factor for the development and the progression in glaucoma optic nerve damage. The reduction of IOP remains mainstream strategy of glaucoma therapy. A large fluctuation of IOP in the circadian rhythm may play a role in the optic nerve damage in glaucoma progression. IOP monitoring provides important information of IOP mean, peak and fluctuation to assist the diagnosis and treatment of glaucoma. With the development of technology, the commonly used methods of IOP monitoring including IOP measurement for diurnal, 24 hours, and habitual body position have evolved to continuous IOP-monitoring using novel device. The influencing factors including tonometer, body position and the light have been taken into account for the reliability of IOP measurement. In this review, we summarized the recent progress in IOP monitoring and the factors affecting the IOP measurements and discussed immense opportunity of IOP-monitoring to better diagnose and to treat for glaucoma.

  17. Implantable intraocular pressure monitoring systems: Design considerations

    KAUST Repository

    Arsalan, Muhammad

    2013-12-01

    Design considerations and limitations of implantable Intraocular Pressure Monitoring (IOPM) systems are presented in this paper. Detailed comparison with the state of the art is performed to highlight the benefits and challenges of the proposed design. The system-on-chip, presented here, is battery free and harvests energy from incoming RF signals. This low-cost design, in standard CMOS process, does not require any external components or bond wires to function. This paper provides useful insights to the designers of implantable wireless sensors in terms of design choices and associated tradeoffs. © 2013 IEEE.

  18. [Contemporary possibilities of intraocular pressure measurement].

    Science.gov (United States)

    Hornová, J; Baxant, A

    2013-10-01

    Authors introduced current possibilities of measuring intraocular pressure (IOP). A list of available methods of monitoring IOP is published; contact measurement method IOP directly on the cornea, but also over upper lid, methodology of minimal contact and non-contact measurement. Following contact methods are described; former measurements of IOP by impression Schiotz tonometer and the current methodology applanation. So far as the gold standard measurement Goldmann applanation tonometer (GAT) is considered, another methodology with applanation measurements are compared: Pascal dynamic contoured tonometer (DCT ), BioResonator - resonant applanation tonometer (ART ), digital applanation tonometer Tonopen and last hit: continuous measurement of IOP by Sensimed Triggerfish. Orientation and rapid assessment is palpation pressure control over the lid and measuring by tonometer Diaton. Rebound tonometer (RBT) iCare belongs to measurements with minimal contact, no need anesthetic drops and fluorescein, therefore a self - home version of IOP measurements (Icare ONE) is developed. Non-contact measurement of IOP by different pneumotonometers is popular for screening assessment of IOP. Reichert Ocular Response Analyzer (ORA) is a non-contact applanation IOP measurement and reveals additional properties of the cornea. In the discussion of a range methodology is evaluated, the experience of other authors and their own experience is compared. For monitoring of patients is necessary to select the most suitable methodology, measure repeatedly and accurately to allow long-term monitoring of intraocular pressure.

  19. Effect of resisting tonometry on intraocular pressure.

    Science.gov (United States)

    Frantz, K A; Peters, R J; Maino, D M; Gunderson, G G

    1994-10-01

    Children and patients with developmental delay frequently resist the procedure of tonometry. Intraocular pressure (IOP) readings, if obtained under stressful circumstances, may have questionable reliability because IOP is influenced by numerous factors characteristic of the uncooperative patient. These factors include possible increases in arterial blood pressure, intraocular vascular engorgement, and pressure on the globe. A study of the effect upon IOP of these factors occurring simultaneously has not been reported previously. We measured IOP using the Tono-Pen on 40 cooperative adults under normal conditions and again under conditions simulating the resistant patient. Paired t-test revealed a statistically significant difference between IOP readings under the two conditions (p IOP under "resistant" conditions showing more variability and averaging 6mmHg higher than under normal conditions. We conclude that IOP readings in resistant patients should be viewed with caution. The possibility of obtaining false high readings in these patients could lead to unnecessary glaucoma evaluations if based only on elevated IOP readings.

  20. The intraocular pressure and diabetes-A correlative study

    Directory of Open Access Journals (Sweden)

    Arora V

    1989-01-01

    Full Text Available In the present study 60 diabetics were examined for intraocular pressure, scleral rigidity and facility of outflow. The intraocular pressure was found higher than in the general population except in patients with proliferative retinopathy. There was no marked difference in scleral rigidity in diabetics. The facility of outflow was lower in diabetic patients.

  1. Intraocular Pressure Lowering Effects of Methanolic Leaf and Stem ...

    African Journals Online (AJOL)

    The intraocular pressure (IOP) lowering activities of the leaf and stem extracts of Gongronema latifolium were investigated on rabbits. Increased intraocular pressure was induced using a combination of prazosin with oral and ophthalmic prednisolone and determined by tonometry. Oral administration of the leaf and stem ...

  2. Effect of prophylactic intraocular pressure-lowering medication on intraocular pressure spikes after intravitreal injections.

    Science.gov (United States)

    Frenkel, Max P C; Haji, Shamim A; Frenkel, Ronald E P

    2010-12-01

    To determine if prophylactic use of intraocular pressure (IOP)-lowering medication is effective in reducing the IOP spikes after intravitreal injections of pegaptanib, bevacizumab, and ranibizumab. Seventy-one patients with exudative age-related macular degeneration received intravitreal injections of 1 of 3 anti-vascular endothelial growth factor medications: 30 patients received pegaptanib (0.09 mL), 47 patients received bevacizumab (0.05 mL), and 42 patients received ranibizumab (0.05 mL). Intraocular pressure-lowering medication, 1 hour prior to the injection, was used 63%, 74%, and 66% of the time in eyes that received pegaptanib, ranibizumab, and bevacizumab, respectively. Intraocular pressure was measured prior to injection, within 1 minute after injection, and every 5 to 10 minutes until the pressure was reduced to a safe level. All 3 intravitreal injections caused significant initial IOP spikes (mean [SD] IOP of 38.5 [11.56] mm Hg in the pegaptanib group, 37.75 [8.36] mm Hg in the ranibizumab group, and 34.88 [10.45] mm Hg in the bevacizumab group). The IOP reduced to less than 30 mm Hg in all 3 groups within 20 minutes. Prophylactic medication did not prevent postinjection IOP spikes. Patients with and without glaucoma showed a similar rate of IOP normalization over time in all 3 groups. Intraocular pressure spikes after intravitreal injection of pegaptanib, ranibizumab, and bevacizumab are common and in most cases transient. Routine prophylactic use of IOP-lowering medications is essentially ineffective in preventing IOP spikes after intravitreal injection of pegaptanib, ranibizumab, and bevacizumab and therefore not necessary before the injection.

  3. New technologies for measuring intraocular pressure.

    Science.gov (United States)

    Garcia-Feijoo, Julian; Martinez-de-la-Casa, Jose María; Morales-Fernandez, Laura; Saenz Frances, Federico; Santos-Bueso, Enrique; Garcia-Saenz, Sofia; Mendez-Hernandez, Carmen

    2015-01-01

    The level of intraocular pressure (IOP) is the main known risk factor for the development and progression of glaucomatous optic neuropathy. Despite Goldmann applanation tonometry (GAT) being the gold standard for determining IOP since the last century, its limitations were obvious from the start and include substantial effects of several eye variables such as axial length, curvature, rigidity, and corneal thickness. These limitations have prompted the development of numerous formulas and nomograms designed to compensate for the ocular characteristics effect on GAT, but none of these methods has been entirely satisfactory. Similarly, as a result of efforts to mitigate some of the limitations of conventional tonometry, several new tonometers have appeared on the scene. © 2015 Elsevier B.V. All rights reserved.

  4. Postprandial Glucose as a Risk Factor for Elevated Intraocular Pressure.

    Science.gov (United States)

    Wu, Chen-Jung; Fang, Wen-Hui; Kao, Tung-Wei; Chen, Ying-Jen; Liaw, Fang-Yih; Chang, Yaw-Wen; Wang, Gia-Chi; Peng, Tao-Chun; Chen, Wei-Liang

    2016-01-01

    The aim of this study was to investigate the association between postprandial glucose and intraocular pressure in a relatively healthy population. We examined 1,439 adults getting a health check-up in a health promotion center at Tri-Service General Hospital (TSGH) in Taiwan between 2012 and 2013. All participants underwent examinations to measure metabolic variables and intraocular pressure. Multiple linear regression analyses were performed to assess the relationship between postprandial glucose and intraocular pressure. The levels of postprandial glucose were divided into quartiles with subjects in the lowest quartile being regarded as the reference group to perform quartile-based analysis. Covariate adjustment was designed for three models for further analysis. Subjects with higher quartiles of postprandial glucose level had a higher systolic blood pressure, a greater waist circumference and an elevated fasting glucose level (all p postprandial glucose and intraocular pressure. The trends of intraocular pressure across increasing quartiles of postprandial glucose were statistically significant (all p for trend postprandial glucose positively correlated with elevated intraocular pressure.

  5. Elevated intraocular pressure in patients with acromegaly.

    Science.gov (United States)

    Quaranta, Luciano; Riva, Ivano; Mazziotti, Gherardo; Porcelli, Teresa; Floriani, Irene; Katsanos, Andreas; Giustina, Andrea; Konstas, Anastasios G P

    2014-07-01

    To evaluate central corneal thickness (CCT) and intraocular pressure (IOP) in a cohort of acromegalic patients, and to correlate CCT with serum levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). Consecutive patients affected by acromegaly underwent a comprehensive endocrinological and ophthalmological evaluation, including serum GH and IGF-1 levels, CCT measured with ultrasonic pachymetry and IOP assessed with Goldmann applanation tonometry. Fourteen patients with acromegaly and 28 healthy controls were included in the study. Acromegalic patients had a statistically higher median CCT (570 μm [range 551.5-638] vs 542.7 μm [range 461.5-610]; p < 0.01) and higher median IOP (17.2 mm Hg [range 14-21] vs 13.7 mm Hg [range 10.5-19]; p < 0.01) than healthy controls. No statistically significant correlation was found among CCT and GH, CCT and IGF-1, IOP and GH, IOP and IGF-1 in the acromegalic group, whereas a statistically significant correlation was documented between CCT and IOP in the entire cohort (Spearman's correlation coefficient: 0.56, p < 0.01). However, when IOP was corrected for CCT no significant difference was found between the two study groups (p = 0.07). Our results suggest that acromegaly is associated with an increased CCT, which could lead to an overestimation of IOP readings as determined with Goldmann applanation tonometry.

  6. Relation between intraocular pressure and size of transverse sinuses

    Energy Technology Data Exchange (ETDEWEB)

    Kantarci, Mecit; Onbas, Omer; Alper, Fatih; Okur, Adnan [Atatuerk University, Department of Radiology, Medical Faculty, Erzurum (Turkey); Dane, Senol; Gumustekin, Kenan [Atatuerk University, Department of Physiology, Medical Faculty, Erzurum (Turkey); Aslankurt, Murat [Atatuerk University, Department of Ophtalmatology, Medical Faculty, Erzurum (Turkey); Yazici, Ahmet Taylan [Beyoglu Goez Egitim ve Arastirma Hastanesi, Istanbul (Turkey)

    2005-01-01

    There are asymmetries in the sizes of transverse sinus and intraocular pressure. The purpose of this study was to investigate possible relationships between the asymmetry of transverse sinuses in TOF MR venography and intraocular pressures of right and left eyes. In this study, subjects were 63 male and 42 female medical school students, aged 18-21 years (mean{+-}SD; 19.72{+-}0.67 years). Subjects with neurological and ophthalmologic disease, particularly dural sinus thrombosis, myopia, trauma and glaucoma, were excluded the study. Subjects were divided into five groups according to the magnitudes of the right- and left-transverse sinuses in MR venography results. There is a functional relation between intraocular pressures of the right and left eyes and asymmetry of the transverse sinus. If the transverse sinus on one side is larger and its venous drainage is greater, the intraocular pressure of the eye on this side is lower. It can be speculated that the transverse sinus size may be associated with pathogenesis of diseases with increased intraocular pressure such as glaucoma. We aim to determine the relation between the size and drainage of transverse sinuses in TOF MR venography and intraocular pressure in patients with open-angle glaucoma in our next study. (orig.)

  7. The effect of blue-blocking and neutral intraocular lenses on circadian photoentrainment and sleep one year after cataract surgery

    DEFF Research Database (Denmark)

    Brøndsted, Adam Elias; Haargaard, Birgitte; Sander, Birgit

    2017-01-01

    PURPOSE: To compare the long-term effect on circadian photoentrainment and sleep in patients implanted with neutral and blue-blocking intraocular lenses 1 year after cataract surgery. METHODS: Randomized, controlled trial involving 67 patients with age-related cataract. Intervention was cataract...... compared with neutral IOLs. Cataract surgery improved the response of ipRGCs and sleep quality. However, the effect of cataract surgery on sleep quality may be unrelated to circadian photoentrainment....

  8. Dysglycemia induces abnormal circadian blood pressure variability

    Directory of Open Access Journals (Sweden)

    Kumarasamy Sivarajan

    2011-11-01

    Full Text Available Abstract Background Prediabetes (PreDM in asymptomatic adults is associated with abnormal circadian blood pressure variability (abnormal CBPV. Hypothesis Systemic inflammation and glycemia influence circadian blood pressure variability. Methods Dahl salt-sensitive (S rats (n = 19 after weaning were fed either an American (AD or a standard (SD diet. The AD (high-glycemic-index, high-fat simulated customary human diet, provided daily overabundant calories which over time lead to body weight gain. The SD (low-glycemic-index, low-fat mirrored desirable balanced human diet for maintaining body weight. Body weight and serum concentrations for fasting glucose (FG, adipokines (leptin and adiponectin, and proinflammatory cytokines [monocyte chemoattractant protein-1 (MCP-1 and tumor necrosis factor-α (TNF-α] were measured. Rats were surgically implanted with C40 transmitters and blood pressure (BP-both systolic; SBP and diastolic; DBP and heart rate (HR were recorded by telemetry every 5 minutes during both sleep (day and active (night periods. Pulse pressure (PP was calculated (PP = SBP-DBP. Results [mean(SEM]: The AD fed group displayed significant increase in body weight (after 90 days; p Conclusion These data validate our stated hypothesis that systemic inflammation and glycemia influence circadian blood pressure variability. This study, for the first time, demonstrates a cause and effect relationship between caloric excess, enhanced systemic inflammation, dysglycemia, loss of blood pressure control and abnormal CBPV. Our results provide the fundamental basis for examining the relationship between dysglycemia and perturbation of the underlying mechanisms (adipose tissue dysfunction induced local and systemic inflammation, insulin resistance and alteration of adipose tissue precursors for the renin-aldosterone-angiotensin system which generate abnormal CBPV.

  9. Intraocular pressure: modulation as treatment for glaucoma.

    Science.gov (United States)

    Caprioli, Joseph; Varma, Rohit

    2011-09-01

    To review the role of intervisit intraocular pressure (IOP) fluctuation as an independent risk factor for glaucoma. Perspective after literature review. Analysis of pertinent publications in the peer-reviewed literature. Disparate findings regarding the role of intervisit IOP variation have been published. IOP variation was a significant risk factor in the Advanced Glaucoma Intervention Study (AGIS), the Collaborative Initial Glaucoma Treatment Study, and other smaller studies. These studies have in common low IOPs (often after surgery) and moderately advanced disease. In the AGIS, when patients were stratified by mean IOP, only those patients with low IOPs showed the detrimental effects of IOP variation. IOP variation was not a significant risk factor in the Early Manifest Glaucoma Treatment Trial, and in 2 separate studies of ocular hypertensives. These studies have in common generally higher IOPs and an earlier stage of glaucoma (or no glaucoma at all). We believe these results are complementary rather than contradictory: existing data suggest that the effects of IOP variation depend on the characteristics of the patient, the baseline IOP, their stage of damage, the type of glaucoma, and other as-yet unknown factors. Practitioners should consider whether patients who are progressing at low mean IOP may benefit from having IOP variation reduced. Single elevated measures of IOP may not be an anomaly or may not be related to compliance, but may identify patients who are at high risk for progressive glaucomatous damage, and thus should be monitored more carefully and potentially treated more aggressively. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. A history of intraocular pressure and its measurement.

    Science.gov (United States)

    Stamper, Robert L

    2011-01-01

    Doctors have not always associated elevated intraocular pressure with the vision loss from glaucoma. Although several individuals appear to have noted firmness of the eye in this condition as far back as the 10th century, elevated intraocular pressure was not routinely assessed until the latter part of the 19th century. von Graefe developed the first instrument for measuring intraocular pressure in 1865. The first reasonably accurate instrument was the Maklakoff applanation tonometer of the late 19th century; it was in widespread use throughout Eastern Europe until relatively recently. Schiötz developed an indentation tonometer that was widely used throughout the world during the first two thirds of the 20th century. Goldmann's applanation tonometer of 1950 began the era of truly accurate intraocular pressure measurement. It is still the most widely used tonometer in the world. Other devices such as the McKay-Marg tonometer (or its offspring the Tono-Pen), the pneumatonometer, and airpuff applanation tonometers are gaining adherents. The dynamic contour tonometer is the first totally new concept in tonometry in over 100 years. It is probably the most accurate of all the tonometers and is relatively independent of corneal biomechanical properties unlike its predecessors. Transpalpebral tonometers are attractive as they do not require topical anesthesia; however, they add the biomechanical properties of the eyelid to the list of potential errors and have not proven very accurate. The future should, hopefully, bring tonometers that can give diurnal or even longer indications of intraocular pressure variation. Although intraocular pressure elevation (or its absence) no longer can be counted on for diagnostic purposes, the role of intraocular pressure in the management of glaucomatous optic neuropathy remains critical.

  11. in Preventing Rise of Intraocular Pressure (Iop)

    African Journals Online (AJOL)

    tulyasys

    INTRODUCTION. Cataract surgery is currently the most common ophthalmic surgical procedure in the world. This procedure involves the extracapsular extraction of the opaque lens fibers and implantation of an intraocular lens (IOL) which restores good vision.[1]. However, posterior capsular opacification (PCO), which is ...

  12. Travoprost lowers intraocular pressure in healthy student volunteers ...

    African Journals Online (AJOL)

    We evaluated the change in diurnal intraocular pressure (IOP) induced by the instillation of single dose travoprost 0.004% and placebo into the eyes of 20 healthy African volunteers in a randomized double masked, placebo controlled, crossover, single centre study. Pulse rate, systolic and diastolic blood pressure, and ...

  13. The Relationship Between Systemic Blood Pressure and Intraocular ...

    African Journals Online (AJOL)

    Some studies in the Caucasian subject showed that systemic blood pressure is related to in-traocular pressure (IOP) and that hypertensive patients are prone to develop raised IOP (glaucoma) but there are few records from black Africans where systemic hypertension is com-mon. We have thus examined IOP in 113 ...

  14. Intraocular Pressure in Pregnant and Non-Pregnant Nigerian Women

    African Journals Online (AJOL)

    Erah

    Estrogen and Progesterone receptors and hormone levels in human myometrium and placenta in term pregnancy. Am J Obstet Gynecol. 2000;. 150:501-505. 15. Klein BE, Klein R and Knudtson MD. Intraocular pressure and systemic blood pressure: longitudinal perspective: the. Beaver Dam Eye Study. Br J Ophthalmol.

  15. Blood pressure modifies retinal susceptibility to intraocular pressure elevation.

    Directory of Open Access Journals (Sweden)

    Zheng He

    Full Text Available Primary open angle glaucoma affects more than 67 million people. Elevated intraocular pressure (IOP is a risk factor for glaucoma and may reduce nutrient availability by decreasing ocular perfusion pressure (OPP. An interaction between arterial blood pressure and IOP determines OPP; but the exact contribution that these factors have for retinal function is not fully understood. Here we sought to determine how acute modifications of arterial pressure will affect the susceptibility of neuronal function and blood flow to IOP challenge. Anaesthetized (ketamine:xylazine Long-Evan rats with low (∼60 mmHg, sodium nitroprusside infusion, moderate (∼100 mmHg, saline, or high levels (∼160 mmHg, angiotensin II of mean arterial pressure (MAP, n = 5-10 per group were subjected to IOP challenge (10-120 mmHg, 5 mmHg steps every 3 minutes. Electroretinograms were measured at each IOP step to assess bipolar cell (b-wave and inner retinal function (scotopic threshold response or STR. Ocular blood flow was measured using laser-Doppler flowmetry in groups with similar MAP level and the same IOP challenge protocol. Both b-wave and STR amplitudes decreased with IOP elevation. Retinal function was less susceptible to IOP challenge when MAP was high, whereas the converse was true for low MAP. Consistent with the effects on retinal function, higher IOP was needed to attenuated ocular blood flow in animals with higher MAP. The susceptibility of retinal function to IOP challenge can be ameliorated by acute high BP, and exacerbated by low BP. This is partially mediated by modifications in ocular blood flow.

  16. Patterns of intraocular pressure elevation after aqueous humor outflow obstruction in rats.

    Science.gov (United States)

    Jia, L; Cepurna, W O; Johnson, E C; Morrison, J C

    2000-05-01

    To determine the diural intraocular pressure (IOP) response of Brown Norway rat eyes after sclerosis of the aqueous humor outflow pathways and its relationship to optic nerve damage. Hypertonic saline was injected into a single episcleral vein in 17 animals and awake IOP measured in both the light and dark phases of the circadian cycle for 34 days. Mean IOP for light and dark phases during the experimental period were compared with the respective pressures of the uninjected fellow eyes. Optic nerve cross sections from each nerve were graded for injury by five independent masked observers. For fellow eyes, mean light- and dark-phase IOP was 21 +/- 1 and 31 +/- 1 mm Hg, respectively. For four experimental eyes, mean IOPs for both phases were not altered. Six eyes demonstrated significant mean IOP elevations only during the dark phase. Of these, five showed persistent, large circadian oscillations, and four had partial optic nerve lesions. The remaining seven eyes experienced significant IOP elevations during both phases, and all had extensive optic nerve damage. Episcleral vein injection of hypertonic saline is more likely to increase IOP during the dark phase than the light. This is consistent with aqueous outflow obstruction superimposed on a circadian rhythm of aqueous humor production. Because these periodic IOP elevations produced optic nerve lesions, both light- and dark-phase IOP determinations are necessary for accurate correlation of IOP history to optic nerve damage in animals housed in a light- dark environment.

  17. Tear Film Functions and Intraocular Pressure Changes in Pregnancy.

    African Journals Online (AJOL)

    AJRH Managing Editor

    Department of Ophthalmology, Ladoke Akintola University of Technology Teaching Hospital, Ogbomoso¹; Department of. Family Medicine, Jericho .... mean was taken as the final reading. Intraocular Pressure. Done in sitting position and the right eye measured first in accordance with convention. A drop of local anesthetic ...

  18. Tear production and intraocular pressure in canine eyes with ...

    African Journals Online (AJOL)

    ... and intraocular pressure (IOP) in dogs with unilateral corneal ulceration using the Schirmer tear test (STT) and rebound (TonoVet®) tonometry. IOP and STT values were recorded in both ulcerated and non-ulcerated (control) eyes of 100 dogs diagnosed with unilateral corneal ulceration. Dogs presented with other ocular ...

  19. Intraocular Pressure Changes During Ramadan Fasting: Effect of ...

    African Journals Online (AJOL)

    Background: Ramadan fasting (RF) alters many systemic milieus. Dehydration from fasting may cause weight loss, while sedentary lifestyle of some Muslims during fasting results in weight gain. RF is associated with low intraocular pressure (IOP). We aim to find out changes in IOP and its relationship to weight changes ...

  20. Investigation of the relationship between intraocular pressure and ...

    African Journals Online (AJOL)

    In a randomized prospective study of volunteers attending Abia State University Optometry Clinic, Uturu, 100 healthy subjects of either sex were enlisted into study, ages 17-39yrs (mean 22-9+2.4) and body weight56to 02kg, in order to establish the association between total body water and intraocular pressure.

  1. comparative study of the intraocular pressure elevation potentials of ...

    African Journals Online (AJOL)

    risk of elevated intraocular pressure (IOP) was compared for dexamethasone phosphate (Decadron ) and fluorometholone acetate (Flarex ) on 32 normotensive volunteers, comprising 12 males and 20 females of the age range 18-40 years. However, age and sex were not considered in the study. An IOP increase of >.

  2. Intraocular pressure and visual acuity across the phases of the ...

    African Journals Online (AJOL)

    Context: Available literature suggests that the pattern of variation in intraocular pressure (IOP) in different phases of the menstrual cycle is inconsistent. Results from studies on the effects of oestrogen and progesterone alone or in combination, on IOP have been conflicting. Aim: To determine the pattern of changes in IOP ...

  3. Short Term Effect of Exercise on Intraocular Pressure of Ocular ...

    African Journals Online (AJOL)

    Aim: Numerous international studies have indicated that several physiological changes can influence the intraocular pressure (IOP) of subjects. In order to assess visual health status through physiological changes, the effects of rest and exercise on IOP were investigated in ocular hypertensive subjects and their ...

  4. Comparison of intraocular pressure reduction of initial and adjunct ...

    African Journals Online (AJOL)

    Objective: The objective was to compare the intraocular pressure (IOP) lowering effect of selective laser trabeculoplasty (SLT) as initial and adjunct therapy in primary open angle glaucoma (POAG). Subjects and Methods: Retrospective chart review of POAG patients who had SLT either as initial or adjunct therapy over a ...

  5. Site of trabeculectomy and control of intraocular pressure: a ...

    African Journals Online (AJOL)

    Background/Objective: To determine the extent to which the site of trabeculectomy affects the extent of drop in intraocular pressure in an African population. Methods: A prospective study involving 54 eyes randomly allocated to a nasal, central and temporal trabeculectomy group and followed up for a period of six months.

  6. Changes in intraocular pressure and horizontal pupil diameter ...

    African Journals Online (AJOL)

    The objective of this study was to determine the effects of topical 0.5% tropicamide, 1% atropine sulphate and 10% phenylephrine hydrochloride ophthalmic solutions on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in the dog during the first hour after treatment. Forty clinically and ophthalmologically ...

  7. Effect of Solanum Melongena (Garden Egg) on Intraocular Pressure ...

    African Journals Online (AJOL)

    Solanum melongena Linn, is one of the medicinal plants of Africa. Its effect on intraocular pressure (IOP) was investigated in 100 normotensive volunteers whose ages ranged between 16 and 30 (mean 22.5+3.4) years, attending the Abia State University Optometry clinic Uturu. Each subject had initial IOP measured before ...

  8. Comparison of Intraocular Pressure Reduction of Initial and Adjunct ...

    African Journals Online (AJOL)

    Intraocular pressure (IOP) is a modifiable risk factor for glaucoma. Reduction of IOP, through medical, surgical, and laser treatment modalities, remains the mainstay of therapy for the disease.[6] The choice of modality is dependent on several factors. The treatment regimen that lowers IOP below a level that is likely to ...

  9. Comparison of Intraocular Pressure Reduction of Initial and Adjunct ...

    African Journals Online (AJOL)

    head cupping, and visual field loss.[1]. Globally, glaucoma is presently the leading cause of irreversible blindness worldwide with a projected estimate of 79.6 million cases by the year 2020.[2] In. Comparison of Intraocular Pressure. Reduction of Initial and Adjunct Selective. Laser Trabeculoplasty for Primary Open Angle.

  10. Intraocular pressure after descemet stripping endothelial keratoplasty (DSEK)

    NARCIS (Netherlands)

    Nieuwendaal, Carla P.; van der Meulen, Ivanka J. E.; Lapid-Gortzak, Ruth; Mourits, Maarten P.

    2013-01-01

    To assess the incidence of elevated intraocular pressure (IOP) after descemet stripping endothelial keratoplasty (DSEK). Retrospective case series. From the start of the technique in our hospital in 2003 until the middle of 2010, 73 eyes underwent DSEK, of which 66 (90.5 %) had a clear graft 1 year

  11. Using an anterior chamber maintainer to control intraocular pressure during phacoemulsification.

    Science.gov (United States)

    Blumenthal, M; Assia, E I; Chen, V; Avni, I

    1994-01-01

    We describe a phacoemulsification technique that uses an anterior chamber maintainer (ACM) to control intraocular pressure. Continuous irrigation through the ACM maintains pressurized intraocular conditions throughout surgery and when the automated system is not activated. Intraocular pressure is stabilized at predetermined levels with minor fluctuations. Viscoelastics can be used in conjunction with the ACM.

  12. Effect of marihuana on intraocular and blood pressure in glaucoma.

    Science.gov (United States)

    Merritt, J C; Crawford, W J; Alexander, P C; Anduze, A L; Gelbart, S S

    1980-03-01

    Marihuana inhalation was accompanied by increased heart rate and decreased intraocular and blood pressure in 18 subjects with heterogenous glaucomas. The hypotensive effects appeared in 60 to 90 minutes as the decrease in intraocular pressure (IOP) appeared to follow the decrease in blood pressure. In addition to any local effect, the mechanism of lowered to any local effect, the mechanism of lowered IOP may also involve the decreased pressure perfusing the ciliary body vasculature as a result of the peripheral vasodilatory properties of marihuana. Postural hypotension, tachycardia, palpitations, and alterations in mental status occurred with such frequency as to mitigate against the routine used in the general glaucoma population. Our data indicate that further research should be directed to local means of delivering the ocular hypotensive cannabinoid to the glaucomatous eye.

  13. The new factors defining variability of circadian’s rhythms of intraocular and perfusion pressure of glaucoma patients

    Directory of Open Access Journals (Sweden)

    N. A. Baranova

    2016-01-01

    Full Text Available Currently, the most scientifically based local risk and progressive factors are elevated levels of intraocular pressure and its instability during the day, caused by local hydromechanical disturbances. However, the other factors affecting the circadian changes of intraocular pressure levels are still evaluated. It was found that light is one of the most important factors affecting the intensity of the cyclical fluctuations of various biological processes, including, and fluctuations of intraocular pressure. At the same time, glaucoma can lead to a variety of sleep disorders, due to a mismatch between cycles «sleep-wake». One if this reason is the death of retinal ganglion cells and their axons. Such damage indirectly lead to a decrease in production of the pigment melanopsin, which is located in the retina. It is not involved in the visual process, but ensures the implementation of circadian rhythms «sleep-wake» and mediated suppression of epiphyseal melatonin. Most likely, melatonin plays a protective role in the occurrence and progression of glaucoma, protecting retinal cells against free radicals and has a direct impact on the intraocular pressure level. Several studies have shown that the circadian change in intraocular pressure levels, and in particular, its substantial reduction, is influenced by melatonin. In this regard, glaucoma is a disease in which the death of retinal cells, including producing melanopsin, a unique opportunity to study violations of cyclic rhythms. Melatonin acts on such established risk factors and progression of glaucoma as hypertension and diabetes. There are published results of the use of melatonin agonists in the experiment and clinical practice. So, in addition to local and systemic hypotensive action, normalizes sleep patients. Data about the melatonin’s effects on the direct and indirect reduction of intraocular pressure, neuroprotective effects and reducing symptoms of depression can

  14. Foldable micro coils for a transponder system measuring intraocular pressure

    Energy Technology Data Exchange (ETDEWEB)

    Ullerich, S.; Schnakenberg, U. [Technische Hochschule Aachen (Germany). Inst. of Materials in Electrical Engineering 1; Mokwa, W. [Technische Hochschule Aachen (Germany). Inst. of Materials in Electrical Engineering 1]|[Fraunhofer Inst. of Microelectronic Circuits and Systems, Duisburg (Germany); Boegel, G. vom [Fraunhofer Inst. of Microelectronic Circuits and Systems, Duisburg (Germany)

    2001-07-01

    A foldable transponder system consisting of a chip and a micro coil for measuring intraocular pressure continuously is presented. The system will be integrated in the haptic of a soft artificial intraocular lens. Calculations of planar micro coils with 6 mm and 10.3 mm in diameter show the limits for planar coils with an outer diameter of 6 mm. For the realisation of the transponder system a 20 {mu}m thick coil with an outer diameter of 10.3 mm, an inner diameter of 7.7 mm, 16 turns and a gap of 20 {mu}m between the windings was selected. Measurements show a good agreement between calculated and measured values. Wireless pressure measurements were carried out showing a linear behaviour of the output signal with respect to the applied pressure. (orig.)

  15. Corneal biomechanical properties and intraocular pressure in high myopic anisometropia.

    Science.gov (United States)

    Xu, Suzhong; Xu, Aiqin; Tao, Aizhu; Wang, Jianhua; Fan, Fan; Lu, Fan

    2010-07-01

    To investigate corneal biomechanical properties and intraocular pressure (IOP) in patients with high myopic anisometropia. Patients with high myopic anisometropia (n = 23) and emmetropic subjects (n = 55) were enrolled. Corneal hysteresis (CH), Goldmann-correlated intraocular pressure (IOPg), corneal resistance factor, and corneal-compensated IOP (IOPcc) were measured with Ocular Response Analyzer. Central corneal thickness was measured by optical coherence tomography. Zeiss IOL-Master determined the values of corneal refractive power and ocular axial length. Significant differences were presented in CH, IOPg, and IOPcc among the high myopic, contralateral, and normal eyes (analysis of variance, Panisometropia. High myopic eyes showed decreased CH, but not corneal resistance factor, which indicates that some aspects of corneal biomechanical properties may be altered in high myopic eye of anisometropia. It is also suggested that anisometropic eyes with different refractive errors do not share the same biomechanical properties, which may impact IOP measurement.

  16. Comparison of the effects of Viscoat and Healon on postoperative intraocular pressure.

    Science.gov (United States)

    Barron, B A; Busin, M; Page, C; Bergsma, D R; Kaufman, H E

    1985-09-15

    We compared the effects of Viscoat and Healon on postoperative increases in intraocular pressure in patients undergoing uncomplicated extracapsular cataract extraction with posterior chamber intraocular lens implantation in a prospective, randomized, single-masked study. Eleven eyes received Viscoat and 13 received Healon. The Viscoat or Healon was aspirated from the anterior chamber with the irrigation-aspiration tip of an automated irrigation-aspiration system at the end of the procedure. No prophylactic intraoperative or postoperative ocular hypotensive agents were used. Intraocular pressure was measured at three, six, 12, and 24 hours postoperatively. Compared with preoperative intraocular pressure, postoperative intraocular pressure was significantly increased in both the Viscoat group and the Healon group. Some postoperative intraocular pressures were as high as 50 to 60 mm Hg, despite removal of the viscoelastic substance at the end of surgery. There was no significant difference in the postoperative intraocular pressures of the Viscoat group and the Healon group.

  17. Systematic Review of Current Devices for 24-h Intraocular Pressure Monitoring.

    Science.gov (United States)

    Ittoop, Sabita M; SooHoo, Jeffrey R; Seibold, Leonard K; Mansouri, Kaweh; Kahook, Malik Y

    2016-10-01

    Glaucoma is a common optic neuropathy that can lead to irreversible vision loss, and intraocular pressure (IOP) is the only known modifiable risk factor. The primary method of treating glaucoma involves lowering IOP using medications, laser and/or invasive surgery. Currently, we rely on in-office measurements of IOP to assess diurnal variation and to define successful management of disease. These measurements only convey a fraction of a patient's circadian IOP pattern and may frequently miss peak IOP levels. There is an unmet need for a reliable and accurate device for 24-h IOP monitoring. The 24-h IOP monitoring devices that are currently available and in development fall into three main categories: self-monitoring, temporary continuous monitoring, and permanent continuous monitoring. This article is a systematic review of current and future technologies for measuring IOP over a 24-h period.

  18. Intraocular pressure estimation using proper orthogonal decomposition

    CSIR Research Space (South Africa)

    Botha, N

    2012-07-01

    Full Text Available for corresponding pressures. The obtained numerical results are compared with the experimental data [5] in Figure 2 for three different age groups, with the corresponding material coefficients (c.f. Equation (2)) given in Table 3. It is clear from the RMSE, which...) for each material coefficient will be used for the sampling range in the POD analysis. Table 3. Optimized material coefficients obtained from the optimization process for the different age groups (maximum values are shown in red, and minimum in blue). C...

  19. Short-term intraocular pressure changes after intravitreal bevacizumab injection

    Directory of Open Access Journals (Sweden)

    Ali Dehghani

    2014-06-01

    Full Text Available Intravitreal injections of anti-vascular endothelial growth factors (anti-VEGFs have become more popular quickly in recent years. Bevacizumab is an anti- vascular endothelial growth factor agent (anti-VEGF used to treat choroidal neovascularization and retinal vascular disorders. Rare long lasting ocular adverse events are reported in the intravitreal injection of this drug that include intraocular inflammation, retinal tears, vitreous hemorrhage, endophtalmitis, and lens changes. One important concern about intravitreal injection of anti-VEGF drug is intraocular pressure (IOP elevation. There are two kinds of IOP elevation. First one is an acute elevation of IOP (after few minutes and the second is delayed IOP elevation (after few months. The prevalence of IOP elevation immediately after injection is significantly high and seems to have the potential risk for optic nerve fiber loss results in decreased vision but fortunately this IOP elevation seems to be transient in most of studies.

  20. The interaction between intracranial pressure, intraocular pressure and lamina cribrosal compression in glaucoma.

    Science.gov (United States)

    McMonnies, Charles W

    2016-05-01

    This review examines some of the biomechanical consequences associated with the opposing intraocular and intracranial forces. These forces compress the lamina cribrosa and are a potential source of glaucomatous pathology. A difference between them creates a displacement force on the lamina cribrosa. Increasing intraocular pressure and/or decreasing intracranial pressure will increase the trans-lamina cribrosa pressure difference and the risk of its posterior displacement, canal expansion and the formation of pathological cupping. Both intraocular pressure and intracranial pressure can be elevated during a Valsalva manoeuvre with associated increases in both anterior and posterior lamina cribrosa loading as well as its compression. Any resulting thinning of or damage to the lamina cribrosa and/or retinal ganglion cell axons and/or astrocyte and glial cells attached to the matrix of the lamina cribrosa and/or reduction in blood flow to the lamina cribrosa may contribute to glaucomatous neuropathy. Thinning of the lamina cribrosa reduces its stiffness and increases the risk of its posterior displacement. Optic nerve head posterior displacement warrants medical or surgical lowering of intraocular pressure; however, compared to intraocular pressure, the trans-lamina cribrosa pressure difference may be more important in pressure-related pathology of the optic nerve head region. Similarly important could be increased compression loading of the lamina cribrosa. Reducing participation in activities which elevate intraocular and intracranial pressure will decrease lamina cribrosa compression exposure and may contribute to glaucoma management and may have prognostic significance for glaucoma suspects. © 2016 The Authors. Clinical and Experimental Optometry © 2016 Optometry Australia.

  1. Associations with Intraocular Pressure in a Large Cohort

    Science.gov (United States)

    Chan, Michelle P.Y.; Grossi, Carlota M.; Khawaja, Anthony P.; Yip, Jennifer L.Y.; Khaw, Kay-Tee; Patel, Praveen J.; Khaw, Peng T.; Morgan, James E.; Vernon, Stephen A.; Foster, Paul J.

    2016-01-01

    Purpose To describe the associations of physical and demographic factors with Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated intraocular pressure (IOPcc) in a British cohort. Design Cross-sectional study within the UK Biobank, a large-scale multisite cohort study in the United Kingdom. Participants We included 110 573 participants from the UK Biobank with intraocular pressure (IOP) measurements available. Their mean age was 57 years (range, 40–69 years); 54% were women, and 90% were white. Methods Participants had 1 IOP measurement made on each eye using the Ocular Response Analyzer noncontact tonometer. Linear regression models were used to assess the associations of IOP with physical and demographic factors. Main Outcome Measures The IOPg and IOPcc. Results The mean IOPg was 15.72 mmHg (95% confidence interval [CI], 15.70–15.74 mmHg), and the mean IOPcc was 15.95 mmHg (15.92–15.97 mmHg). After adjusting for covariates, IOPg and IOPcc were both significantly associated with older age, male sex, higher systolic blood pressure (SBP), faster heart rate, greater myopia, self-reported glaucoma, and colder season (all P corneal biomechanical properties. The increase in both IOPg and IOPcc with age was greatest among those of mixed ethnicities, followed by blacks and whites. The same set of covariates explained 7.4% of the variability of IOPcc but only 5.3% of the variability of IOPg. Conclusions This analysis of associations with IOP in a large cohort demonstrated that some variables clearly have different associations with IOPg and IOPcc, and that these 2 measurements may reflect different biological characteristics. PMID:26795295

  2. Circadian clock-mediated regulation of blood pressure.

    Science.gov (United States)

    Douma, Lauren G; Gumz, Michelle L

    2017-12-02

    Most bodily functions vary over the course of a 24h day. Circadian rhythms in body temperature, sleep-wake cycles, metabolism, and blood pressure (BP) are just a few examples. These circadian rhythms are controlled by the central clock in the suprachiasmatic nucleus (SCN) of the hypothalamus and peripheral clocks located throughout the body. Light and food cues entrain these clocks to the time of day and this synchronicity contributes to the regulation of a variety of physiological processes with effects on overall health. The kidney, brain, nervous system, vasculature, and heart have been identified through the use of mouse models and clinical trials as peripheral clock regulators of BP. The dysregulation of this circadian pattern of BP, with or without hypertension, is associated with increased risk for cardiovascular disease. The mechanism of this dysregulation is unknown and is a growing area of research. In this review, we highlight research of human and mouse circadian models that has provided insight into the roles of these molecular clocks and their effects on physiological functions. Additional tissue-specific studies of the molecular clock mechanism are needed, as well as clinical studies including more diverse populations (different races, female patients, etc.), which will be critical to fully understand the mechanism of circadian regulation of BP. Understanding how these molecular clocks regulate the circadian rhythm of BP is critical in the treatment of circadian BP dysregulation and hypertension. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Ambulatory 24-h intraocular pressure monitoring in the management of glaucoma.

    Science.gov (United States)

    Mansouri, Kaweh; Weinreb, Robert N

    2015-05-01

    To review current status and future of ambulatory 24-h intraocular pressure monitoring. Despite important advances in the diagnosis and management of glaucoma during the last decade, the fundamental understanding of intraocular pressure, its only modifiable risk factor, remains elusive. The current practice of single intraocular pressure measurements during a clinic visit does not adequately reflect the variability of intraocular pressure throughout the 24-h day. There has been considerable progress recently with the prototype and commercial introduction of continuous 24-h intraocular pressure monitoring devices. Implantable intraocular pressure sensors have the advantage to directly measure intraocular pressure over many months and years, whereas temporary (contact lens based) approaches provide a noninvasive alternative for repeated 24-h periods. This review provides an overview of implantable devices as well as a critical assessment of a 24-h contact lens sensor. Recent advances in microelectromechanical systems and nanoelectromechanical systems have enabled the development of 24-h intraocular pressure monitoring devices. Once these technologies have shown their safety and efficacy, larger questions as to the data interpretation and handling will arise. It is likely that the use of 24-h intraocular pressure monitoring will herald fundamental changes in our understanding and management of glaucoma.

  4. Is 24-hour Intraocular Pressure Monitoring Necessary in Glaucoma?

    Science.gov (United States)

    Mansouri, Kaweh; Weinreb, Robert N.; Medeiros, Felipe A.

    2013-01-01

    Although intraocular pressure (IOP) is the only treatable risk factor for glaucoma, its 24-hour behavior is poorly understood. Conflicting information is available in the literature with regard to the importance and predictive value of IOP peaks and fluctuations on the risk of glaucoma development and progression. This may be secondary to lack of prospective studies designed to address this issue. This article critically reviews the current evidence for the importance of 24-h IOP measurements in glaucoma and discusses shortcomings of current methods to assess 24-h IOP data, drawing attention to new developments in this field. PMID:23697618

  5. Twenty-four hour intraocular pressure measurements and home tonometry.

    Science.gov (United States)

    Meier-Gibbons, Frances; Berlin, Michael S; Töteberg-Harms, Marc

    2018-03-01

    IOP is the only treatable risk factor contributing to glaucoma and most management and treatment of glaucoma is based on IOP. However, current IOP measurements are limited to office hours and control of glaucoma in many patients would benefit from the ability to monitor IOP diurnally so as not to miss abnormal pressures, which occur outside of office hours Consequently, to improve patient care, the ability to enable accurate and minimally disruptive diurnal IOP monitoring would improve caring for these patients. The studies we selected for this review can be divided into three categories: self-/home-tonometry, continuous invasive intraocular pressure measurements, and continuous noninvasive ocular measurements. The desire to obtain better insight in our patients' true diurnal IOP has led to the development of home-tonometers, in addition to extraocular and intraocular continuous pressure measurement devices. All of the devices have respective advantages and disadvantages, but none to date completely fulfills the goal of providing a true diurnal IOP profile.Video abstracthttp://links.lww.com/COOP/A27.

  6. Tear Film Functions and Intraocular Pressure Changes in Pregnancy.

    Science.gov (United States)

    Ibraheem, Waheed A; Ibraheem, Anifat B; Tjani, Aramide M; Oladejo, Samuel; Adepoju, Susan; Folohunso, Bukola

    2015-12-01

    Pregnancy related ocular changes are diverse with varied clinical outcome. In a cross-sectional, descriptive case control study, we evaluated tear film functions and intraocular pressure during pregnancy and compared the results with non-pregnant women. A total of 270 participants including 165 healthy pregnant women and 105 non-pregnant who were free from systemic and pre-pregnancy eye diseases were investigated. Snellen's chart, fluorescein dye, No 41 Whatman filter paper, Perkin's tonometer were employed to assess visual acuity, tear break up time (TBUT), Schirmer's test (ST), intraocular pressure (IOP) on all subjects. The mean values for IOP (mmHg), TBUT (seconds) and Schirmer's reading (mm) were: 13.24 ± 2.18, 25.05 ± 9.30, 37.03 ± 17.06 and 14.24 ± 2.66, 22.10 ± 10.81, 50.13 ± 19.10 for cases and controls respectively. Schirmer's reading (SR) was significantly lower among pregnant women. Only age had a statistically significant association with the measured parameters. Our study revealed reduced SR during pregnancy. We suggest routine ocular assessment for pregnant women to forestall deleterious sequelae of dry eye.

  7. A new device to noninvasively estimate the intraocular pressure produced during ocular compression

    Directory of Open Access Journals (Sweden)

    Korenfeld MS

    2016-01-01

    Full Text Available Michael S Korenfeld,1,2 David K Dueker3 1Comprehensive Eye Care, Ltd., 2Department of Ophthalmology and Visual Sciences, Washington University, Washington, MO, USA; 3Hamad Medical Corporation, Doha, Qatar Purpose: To describe a noninvasive instrument that estimates intraocular pressure during episodes of external globe compression and to demonstrate the accuracy and reliability of this device by comparing it to the intraocular pressures simultaneously and manometrically measured in cannulated eyes. Methods: A thin fluid-filled bladder was constructed from flexible and inelastic plastic sheeting and was connected to a pressure transducer with high pressure tubing. The output of the pressure transducer was sent to an amplifier and recorded. This device was validated by measuring induced pressure in the fluid-filled bladder while digital pressure was applied to one surface, and the other surface was placed directly against a human cadaver eye or in vivo pig eye. The human cadaver and in vivo pig eyes were each cannulated to provide a manometric intraocular pressure control. Results: The measurements obtained with the newly described device were within ~5% of simultaneously measured manometric intraocular pressures in both a human cadaver and in vivo pig eye model for a pressure range of ~15–100 mmHg. Conclusion: This novel noninvasive device is useful for estimating the intraocular pressure transients induced during any form of external globe compression; this is a clinical setting where no other devices can be used to estimate intraocular pressure. Keywords: glaucoma, intraocular pressure, tonometer, ocular compression

  8. Intraocular hemorrhage in sudden increased intracranial pressure (Terson syndrome).

    Science.gov (United States)

    Gutierrez Diaz, A; Jimenez Carmena, J; Ruano Martin, F; Diaz Lopez, P; Muñoz Casado, M J

    1979-01-01

    We examined 19 cases with SAH, 4 of which presented intraocular hemorrhages (retinal, subhyaloid and in vitreous). The mortality rate was 50% when the intraocular hemorrhages were present compared to 20% when they were absent.

  9. The synergistic effect of inflammation and metabolic syndrome on intraocular pressure: A cross-sectional study.

    Science.gov (United States)

    Lee, I-Te; Wang, Jun-Sing; Fu, Chia-Po; Chang, Chia-Jen; Lee, Wen-Jane; Lin, Shih-Yi; Sheu, Wayne Huey-Herng

    2017-09-01

    Intraocular pressure is associated with metabolic syndrome. C-reactive protein (CRP) is associated with cardiovascular disease, irrespective of the presence of metabolic syndrome. In this study, we examined the synergistic effect of CRP and metabolic syndrome on intraocular pressure.A total of 1041 subjects were included for data analyses in this cross-sectional study. Intraocular pressure was measured using a noncontact tonometer, and serum CRP levels were measured using a commercially available kit.The intraocular pressure was significantly higher in the subjects with metabolic syndrome than in those without (14.1 ± 3.0 vs 13.4 ± 3.0 mm Hg, P = .002). Furthermore, intraocular pressures significantly increased according to CRP tertiles (13.1 ± 3.0, 13.7 ± 3.0, and 13.8 ± 3.0 mm Hg from the lowest to highest tertile of CRP, respectively; P = .002). The highest intraocular pressure was observed in subjects with metabolic syndrome in the highest CRP tertile (P value for trend syndrome and that high CRP levels were significantly associated with high intraocular pressure (95% confidence interval: 0.080-1.297, P = .027).In conclusion, systemic inflammation, reflected by serum CRP levels, is associated with high intraocular pressure in subjects with and without metabolic syndrome.

  10. Change in Intraocular Pressure During Point-of-Care Ultrasound

    Directory of Open Access Journals (Sweden)

    Berg, Cameron

    2015-03-01

    Full Text Available Introduction: Point-of-care ocular ultrasound (US is a valuable tool for the evaluation of traumatic ocular injuries. Conventionally, any maneuver that may increase intraocular pressure (IOP is relatively contraindicated in the setting of globe rupture. Some authors have cautioned against the use of US in these scenarios because of a theoretical concern that an US examination may cause or exacerbate the extrusion of intraocular contents. This study set out to investigate whether ocular US affects IOP. The secondary objective was to validate the intraocular pressure measurements obtained with the Diaton® as compared with standard applanation techniques (the Tono-Pen®.   Methods: We enrolled a convenience sample of healthy adult volunteers. We obtained the baseline IOP for each patient by using a transpalpebral tonometer. Ocular US was then performed on each subject using a high-frequency linear array transducer, and a second IOP was obtained during the US examination. A third IOP measurement was obtained following the completion of the US examination. To validate transpalpebral measurement, a subset of subjects also underwent traditional transcorneal applanation tonometry prior to the US examination as a baseline measurement. In a subset of 10 patients, we obtained baseline pre-ultrasound IOP measurements with the Diaton® and Tono-Pen®, and then compared them.   Results: The study included 40 subjects. IOP values during ocular US examination were slightly greater than baseline (average +1.8mmHg, p=0.01. Post-US examination IOP values were not significantly different than baseline (average -0.15mmHg, p=0.42. In a subset of 10 subjects, IOP values were not significantly different between transpalpebral and transcorneal tonometry (average +0.03mmHg, p=0.07.   Conclusion: In healthy volunteer subjects, point-of-care ocular US causes a small and transient increase in IOP. We also showed no difference between the Diaton® and Tono-Pen® methods

  11. Intraocular pressure in very low birth weight preterm infants and its association with postconceptional age

    Directory of Open Access Journals (Sweden)

    Rodrigo L. Lindenmeyer

    2012-11-01

    Full Text Available OBJECTIVE: To evaluate intraocular pressure in very low birth weight preterm infants and correlate it with postconceptional age. METHODS: The intraocular pressure in a prospective cohort of very low birth weight premature infants (defined as a birth weight <1,500 g and gestational age <32 weeks admitted to Hospital de Clínicas de Porto Alegre , Brazil was evaluated weekly. The evaluated outcome was the variation in the intraocular pressure following changes in the postconceptional age (defined as the gestational age at birth plus the age in weeks at the time of examination in the weeks following preterm birth. Mixed-effects models were used for the statistical analysis to determine the intraocular pressure variation according to postconceptional age, and means and 10th and 90th percentiles were calculated for the intraocular pressure values. RESULTS: Fifty preterm infants with a mean gestational age of 29.7 ± 1.6 weeks and a mean birth weight of 1,127.7 ± 222.7 g were evaluated. The mean intraocular pressure for the entire cohort considering both eyes was 14.9 ± 4.5 mmHg, and 13.5% of all recorded intraocular pressure values were greater than 20 mmHg. The analysis revealed a mean reduction in the intraocular pressure of 0.29 mmHg for each increase in postconceptional age (p = 0.047; 95% CI: -0.58 to -0.0035. The mean intraocular pressure (P10-P90 decreased from 16.3 mmHg (10.5222.16 at 26.3 weeks to 13.1 mmHg (7.28-18.92 at 37.6 weeks of postconceptional age. CONCLUSIONS: The mean intraocular pressure in very low birth weight preterm infants was 14.9 ± 4.5 mmHg. This value decreased 0.29 mmHg per week as the postconceptional age increased.

  12. 24-h monitoring devices and nyctohemeral rhythms of intraocular pressure.

    Science.gov (United States)

    Aptel, Florent; Weinreb, Robert N; Chiquet, Christophe; Mansouri, Kaweh

    2016-11-01

    Intraocular pressure (IOP) is not a fixed value and varies over both the short term and periods lasting several months or years. In particular, IOP is known to vary throughout the 24-h period of a day, defined as a nyctohemeral rhythm in humans. In clinical practice, it is crucial to evaluate the changes in IOP over 24 h in several situations, including the diagnosis of ocular hypertension and glaucoma (IOP is often higher at night) and to optimize the therapeutic management of glaucoma. Until recently, all evaluations of 24-h IOP rhythm were performed using repeated IOP measurements, requiring individuals to be awakened for nocturnal measurements. This method may be imperfect, because it is not physiologic and disturbs the sleep architecture, and also because it provides a limited number of time point measurements not sufficient to finely asses IOP changes. These limitations may have biased previous descriptions of physiological IOP rhythm. Recently, extraocular and intraocular devices integrating a pressure sensor for continuous IOP monitoring have been developed and are available for use in humans. The objective of this article is to present the contributions of these new 24-h monitoring devices for the study of the nyctohemeral rhythms. In healthy subjects and untreated glaucoma subjects, a nyctohemeral rhythm is consistently found and frequently characterized by a mean diurnal IOP lower than the mean nocturnal IOP, with a diurnal bathyphase - usually in the middle or at the end of the afternoon - and a nocturnal acrophase, usually in the middle or at the end of the night. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. The Effect of Cataract Surgery on Circadian Photoentrainment: A Randomized Trial of Blue-Blocking versus Neutral Intraocular Lenses.

    Science.gov (United States)

    Brøndsted, Adam Elias; Sander, Birgit; Haargaard, Birgitte; Lund-Andersen, Henrik; Jennum, Poul; Gammeltoft, Steen; Kessel, Line

    2015-10-01

    Cataract decreases blue light transmission. Because of the selective blue light sensitivity of the retinal ganglion cells governing circadian photoentrainment, cataract may interfere with normal sleep-wake regulation and cause sleep disturbances. The purpose was to investigate the effect of cataract surgery on circadian photoentrainment and to determine any difference between blue-blocking and neutral intraocular lenses (IOLs). The study was a single-center, investigator-driven, double-masked, block-randomized clinical trial. One eye in 76 patients with bilateral age-related cataract eligible for cataract surgery was included. Intervention was cataract surgery by phacoemulsification. Patients were randomized to receive a blue-blocking or neutral IOL. Primary outcome was activation of intrinsic photosensitive ganglion cells using post-illumination pupil response (PIPR) to blue light from 10 to 30 seconds after light exposure as a surrogate measure. Secondary outcomes were circadian rhythm analysis using actigraphy and 24-hour salivary melatonin measurements. Finally, objective and subjective sleep quality were determined by actigraphy and the Pittsburgh Sleep Quality Index. The blue light PIPR increased 2 days (17%) and 3 weeks (24%) after surgery (P blue-blocking and neutral IOLs, whereas low preoperative blue light transmission was inversely associated with an increase in PIPR (P = 0.021) and sleep efficiency (P = 0.048). Cataract surgery increases photoreception by the photosensitive retinal ganglion cells. Because of inconsistency between the significant findings and the many parameters that were unchanged, we can conclude that cataract surgery does not adversely affect the circadian rhythm or sleep. Longer follow-up time and fellow eye surgery may reveal the significance of the subtle changes observed. We found no difference between blue-blocking and neutral IOLs, and, because of the minor effect of surgery in itself, an effect of IOL type seems highly unlikely

  14. Continuous intraocular pressure (IOP) measurement during glaucoma drainage device implantation.

    Science.gov (United States)

    Gouws, Pieter; Moss, Edward B; Trope, Graham E; Ethier, C Ross

    2007-05-01

    To measure the effect of the implantation of a glaucoma drainage device on the intraocular pressure (IOP) during the implantation surgery. We implanted telemetry devices into 1 eye each of 3 white New Zealand rabbits. Once the telemetry was found to be working and the rabbits had fully recovered from surgery, we implanted a glaucoma drainage device into the same eye while continually monitoring the IOP with the telemetry devices. During surgery IOP was extremely variable, however, extremely high pressures were recorded in association with suturing and viscoelastic injection. The fact that pressures are significantly raised during some surgical events should make surgeons aware that manipulations need to be kept as short as possible to prevent further potential damage to glaucomatous optic nerves. There is a possibility of dramatically raising the IOP during surgery, specifically in complicated cases requiring prolonged manipulation and/or forcible deepening of the anterior chamber. In such cases, it may be a good idea to time the duration of manipulations to prevent prolonged episodes of elevated IOP.

  15. Correlation of the intraocular pressure with increased intracranial pressure in rabbits

    Directory of Open Access Journals (Sweden)

    Eskandari H

    2000-08-01

    Full Text Available Although measurement of intracranial pressure by noninvasive methods has been suggested, but mainly invasive methods are used for this purpose-Increase in episcleral venous pressure can be expected to result in a linear increase in intraocular pressure. Congested oculat veins with capillary leakage and hemorrhage are seen when the ICP is increased, thus theoretically measurement of intraocular pressure can be a procedure for estimation of the ICP. This study was performed to find whether there is andy relationship between intraocular pressure and ICP, so we used 12 albino rabbits in two divided groups. Our study was not designed to elucidate the mechanism of change but merely to record any changes observed. All measures except an increase in ICP were applied on the test group as well as on the control group. After general anesthesia with the combination of ketamin, rampune, and pentobarbital a burr hole was made in the lambda region of the skull and a cannula was placed in the subdural space. The ICP in the test group increased up to 15 mmHg and was constant throughout the experiment. Intraocular pressure was measured by Schiotz tonometers afte general anesthesia, after cannulation of the skull, and immediately after increasing the ICP which was repated in 15 minutes interval for 4 hours. There was no statistical difference between the two groups (P:0.997 . results show that neither cannulation nor general anesthesia for 4 hours produce alteration in IOP in the control group nor increasing of the ICP to level of 15 mmHg produces any alteration in IOP on the test group.

  16. Circadian pattern of blood pressure in normal pregnancy and preeclampsia.

    Science.gov (United States)

    Gupta, Hem Prabha; Singh, R K; Singh, Urmila; Mehrotra, Seema; Verma, N S; Baranwal, Neelam

    2011-08-01

    AIMS #ENTITYSTARTX00026; To find out the circadian pattern of blood pressure in normotensive pregnant women and in women with preeclampsia. A cross-sectional prospective observational case control study. Blood pressure was sampled in thirty-five normotensive pregnant women (control) and thirty five preeclamptic women (study group) by using non-invasive automatic ambulatory blood pressure monitoring machine for 72 h. Blood pressure (BP) was not constant over 24 h period and it oscillated from time to time in control group. BP was maximum during early part of afternoon. However, in preeclampsia besides quantitative increase in BP, circadian BP oscillations were less pronounced and in around 50% subjects BP was maximum during evening and night hours. Both systolic and diastolic BP showed definite reproducible circadian pattern in both preeclamptic and normotensive pregnant women. This pattern both quantitatively and qualitatively was different in preeclamptic women. Standardized 24 h BP monitoring allows quantitative and qualitative evaluation of hypertensive status and is important for timing and dosing of antihypertensive medications.

  17. Intraocular pressure in postmenopausal Nigerian women with and without systemic hypertension

    Directory of Open Access Journals (Sweden)

    J. A. Ebeigbe

    2011-12-01

    Full Text Available Background: Mean intraocular pressure (IOP in postmenopausal women has been reported higher than that in menstruating women. Also, intraocular pressure is said to be positively correlated with systemic blood pressure. No previous study in Nigeria has compared intraocular pressure in postmenopausal women with and without systemic hypertension. Purpose: To investigate the effects of menopause on intraocular pressure in subjects with and without high blood pressure. Methods: Normotensive and hypertensive premenopausal and postmenopausal subjects in the   same agerange of 45 to 55 years were studied. Intraocular pressure was measured with the hand-held Kowa applanation tonometer.  Blood pressure was taken in the sitting position at the right upper arm using a manual mercury sphygmomanometer with the right cuff size. The average of two readings was recorded. Results: Mean IOP for premenopausal normotensive women was 14.58 ± 2.56 mmHg whilethat of postmenopausal normotensive women was16.15 ± 1.80 mmHg (p<0.05.  Also, the difference in mean IOP between premenopausal hypertensive (16.58 ± 3.23 mmHg and postmenopausal hypertensive women (18.24 ± 3.89 mmHgwas statistically significant (p<0.05. A statistically significant and positive correlation was observed between IOP and systemic blood pressure in postmenopausal hypertensive women, p<0.05.Conclusion: Menopause significantly increases intraocular pressure. Mean intraocular pressure of hypertensive postmenopausal women was significantly higher than that of normotensive post-menopausal women, (p<0.05. Knowledge of the normal level of intraocular pressure during various stages of the female reproductive cycle may help during glaucoma screening. (S Afr Optom 2011 70(3 117-122

  18. The Application of a Contact Lens Sensor in Detecting 24-Hour Intraocular Pressure-Related Patterns

    Directory of Open Access Journals (Sweden)

    Sarah C. Xu

    2016-01-01

    Full Text Available Glaucoma is one of the leading causes of blindness worldwide. Recent studies suggest that intraocular pressure (IOP fluctuations, peaks, and rhythm are important factors in disease advancement. Yet, current glaucoma management remains hinged on single IOP measurements during clinic hours. To overcome this limitation, 24-hour IOP monitoring devices have been employed and include self-tonometry, permanent IOP, and temporary IOP monitoring. This review discusses each IOP measuring strategy and focuses on the recently FDA-approved contact lens sensor (CLS. The CLS records IOP-related ocular patterns for 24 hours continuously. Using the CLS, IOP-related parameters have been found to be associated with the rate of visual field progression in primary open-angle glaucoma, disease progression in primary angle-closure glaucoma, and various clinical variables in ocular hypertension. The CLS has been used to quantify blink rate and limbal strain and measure the circadian rhythm in a variety of disease states including normal-tension glaucoma and thyroid eye disease. The effects of various IOP-lowering interventions were also characterized using the CLS. CLS provides a unique, safe, and well-tolerated way to study IOP-related patterns in a wide range of disease states. IOP-related patterns may help identify patients most at risk for disease progression and assist with the development of tailored treatments.

  19. Continuous 24-hour intraocular pressure monitoring for glaucoma--time for a paradigm change.

    Science.gov (United States)

    Mansouri, K; Weinreb, R

    2012-03-28

    Glaucoma is the main cause of irreversible blindness and intraocular pressure (IOP) is its only modifiable risk factor. The importance of robust lowering of IOP for prevention of glaucoma onset and progression is well established. Although IOP is a dynamic parameter with individual circadian rhythms, current management usually relies on single IOP measurements during regular clinic hours performed a few times a year. Recent technological advances have provided clinicians with tools for continuous IOP monitoring during a 24 hour period in an ambulatory setting. There are two approaches being investigated. The first is permanent IOP monitoring through an implantable sensor and the other is temporary monitoring through a contact lens sensor. In this article, we discuss the shortcomings of the current gold standard for tonometry (Goldmann Applanation Tonometry) and the current experience with the first commercially available continuous 24 hour IOP monitoring technology (SENSIMED Triggerfish®); a telemetric contact lens sensor produced by a Swiss start-up company (Sensimed AG, Lausanne, Switzerland). Recent studies suggest that 24 hour continuous monitoring of IOP can be integrated into clinical practice and have the potential to contribute to the reduction of glaucoma-related vision loss.

  20. Intraocular pressure variations during zygomatic fracture reduction and fixation: a clinical study.

    LENUS (Irish Health Repository)

    Murray, Dylan J

    2012-02-03

    BACKGROUND: The reduction of midface fractures has been associated with the rare but devastating complication of blindness. An increase in intraocular pressure is important in the mechanism of blindness in this setting. In this study, the authors assessed the intraocular pressure in patients who underwent zygomatic fracture reduction (with or without fixation). METHODS: Using applanation tonometry, 29 patients underwent intraocular pressure measurements before, during, and after fracture fixation. The contralateral pressures were measured and used as the control. RESULTS: There were 29 patients with a mean age of 35 years, and the mean time to surgery was 5 days. Preoperatively, all patients had normal intraocular pressures and normal visual acuity. All patients underwent a Gillies lift and 18 patients required open reduction and fixation of the frontozygomatic suture (n = 4) or the infraorbital margin (n = 2), and the remainder (n = 12) required fixation of both points. There was no statistically significant increase in the intraocular pressures following the reduction of uncomplicated zygomatic fractures. Statistically significant pressure reductions were noted immediately after reduction and fixation. CONCLUSIONS: The surgical reduction of uncomplicated zygomatic fractures has no adverse effect on the intraocular pressure. It is the authors\\' opinion that adjunctive measures to reduce the pressures are unnecessary.

  1. Computerized invasive measurement of time-dependent intraocular pressure

    Directory of Open Access Journals (Sweden)

    T.V.O. Campos

    2006-09-01

    Full Text Available Several methods have been described to measure intraocular pressure (IOP in clinical and research situations. However, the measurement of time varying IOP with high accuracy, mainly in situations that alter corneal properties, has not been reported until now. The present report describes a computerized system capable of recording the transitory variability of IOP, which is sufficiently sensitive to reliably measure ocular pulse peak-to-peak values. We also describe its characteristics and discuss its applicability to research and clinical studies. The device consists of a pressure transducer, a signal conditioning unit and an analog-to-digital converter coupled to a video acquisition board. A modified Cairns trabeculectomy was performed in 9 Oryctolagus cuniculus rabbits to obtain changes in IOP decay parameters and to evaluate the utility and sensitivity of the recording system. The device was effective for the study of kinetic parameters of IOP, such as decay pattern and ocular pulse waves due to cardiac and respiratory cycle rhythm. In addition, there was a significant increase of IOP versus time curve derivative when pre- and post-trabeculectomy recordings were compared. The present procedure excludes corneal thickness and error related to individual operator ability. Clinical complications due to saline infusion and pressure overload were not observed during biomicroscopic evaluation. Among the disadvantages of the procedure are the requirement of anesthesia and the use in acute recordings rather than chronic protocols. Finally, the method described may provide a reliable alternative for the study of ocular pressure dynamic alterations in man and may facilitate the investigation of the pathogenesis of glaucoma.

  2. Reliable intraocular pressure measurement using automated radio-wave telemetry

    Directory of Open Access Journals (Sweden)

    Paschalis EI

    2014-01-01

    Full Text Available Eleftherios I Paschalis,* Fabiano Cade,* Samir Melki, Louis R Pasquale, Claes H Dohlman, Joseph B CiolinoMassachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA*These authors contributed equally to this workPurpose: To present an autonomous intraocular pressure (IOP measurement technique using a wireless implantable transducer (WIT and a motion sensor.Methods: The WIT optical aid was implanted within the ciliary sulcus of a normotensive rabbit eye after extracapsular clear lens extraction. An autonomous wireless data system (AWDS comprising of a WIT and an external antenna aided by a motion sensor provided continuous IOP readings. The sensitivity of the technique was determined by the ability to detect IOP changes resulting from the administration of latanoprost 0.005% or dorzolamide 2%, while the reliability was determined by the agreement between baseline and vehicle (saline IOP.Results: On average, 12 diurnal and 205 nocturnal IOP measurements were performed with latanoprost, and 26 diurnal and 205 nocturnal measurements with dorzolamide. No difference was found between mean baseline IOP (13.08±2.2 mmHg and mean vehicle IOP (13.27±2.1 mmHg (P=0.45, suggesting good measurement reliability. Both antiglaucoma medications caused significant IOP reduction compared to baseline; latanoprost reduced mean IOP by 10% (1.3±3.54 mmHg; P<0.001, and dorzolamide by 5% (0.62±2.22 mmHg; P<0.001. Use of latanoprost resulted in an overall twofold higher IOP reduction compared to dorzolamide (P<0.001. Repeatability was ±1.8 mmHg, assessed by the variability of consecutive IOP measurements performed in a short period of time (≤1 minute, during which the IOP is not expected to change.Conclusion: IOP measurements in conscious rabbits obtained without the need for human interactions using the AWDS are feasible and provide reproducible results.Keywords: IOP, pressure transducer, wireless, MEMS, implant, intraocular

  3. A STUDY ON VARIATION OF INTRAOCULAR PRESSURE AND OCULAR PERFUSION PRESSURE OVER A 24-HOUR PERIOD

    Directory of Open Access Journals (Sweden)

    Maheswari Parakkai Subramaniam

    2017-08-01

    Full Text Available BACKGROUND Glaucoma is the second leading cause of blindness globally. Intraocular pressure and vascular risk factors have been proposed to be important risk factors in the development of glaucoma. The aim of this study is to describe the variation of ocular perfusion pressure and intraocular pressure in normal subjects, glaucoma suspects, which include Ocular Hypertension (OHT suspects and Normotensive Glaucoma (NTG suspects and established primary open-angle glaucoma patients over a period of 24 hours. MATERIALS AND METHODS A cross-sectional study was conducted for 24 hours at the glaucoma services of a tertiary eye care hospital at Chennai. Totally, 30 eyes (right eye of 30 patients were included and they were categorised into four groups- Group A (normal- Subjects with normal IOP, fields and normal optic nerve head and RNFL on fundus examination; 12 eyes were included. Group B (ocular hypertension suspects- Subjects with normal fields and normal optic nerve head on fundus examination, but with elevated IOP; 8 eyes were included. Group C (normotensive glaucoma NTG suspects- Subjects with normal IOP and fields, but with optic nerve head changes like increased cup disc ratio, focal notching, focal NRR thinning or RNFL wedge defects; 8 eyes were included. Group D (primary open-angle glaucoma- Subjects with increased IOP, typical glaucomatous field defects and optic nerve head and RNFL changes suggestive of glaucoma; 7 eyes were included. A thorough baseline investigation including applanation tonometry with central corneal thickness correction, gonioscopy and fields by automated perimeter (Octopus 301 perimeter were done. Intraocular pressure and blood pressure were recorded at 12 p.m., 6 p.m., 12 a.m. and 6 a.m. The systolic, diastolic and mean ocular perfusion pressures were calculated. RESULTS Four parameters viz. intraocular pressure, systolic perfusion pressure, diastolic perfusion pressure and mean perfusion pressure were analysed over a

  4. Is the observed lowering of intraocular pressure due to treatment?

    Directory of Open Access Journals (Sweden)

    Ravi Thomas

    2013-01-01

    Full Text Available Objective: Use Bayes′ theorem to estimate the intraocular pressure (IOP lowering effect of medical treatment initiated for glaucoma and determine if IOP comparisons to the baseline IOP of the same eye is clinically useful. Materials and Methods: The probability that treatment with prostaglandin is responsible for an observed 20% decrease in IOP with prostaglandin treatment was calculated using Bayes′ theorem using the following available information: the probability of a 20% decrease in IOP given treatment with prostaglandin, the probability of a treatment effect using prostaglandin and the overall probability of a 20% decrease in IOP. The calculations were repeated to account for a possible 2 mmHg overestimation of effect caused by measurement error in performing applanation tonometry. Results: The probability that treatment is responsible for an observed 20% decrease in IOP following initiation of treatment with a prostaglandin was 99%. After adjusting for measurement error this probability was 98%. Obtaining two IOP measurements marginally increased the probability. Conclusion: Following initiation of treatment with prostaglandin, Bayes′ theorem allows us to infer that treatment effect is the most likely explanation for an observed 20% decrease in IOP from the baseline; this inference remains even after adjusting for known measurement error. The high probability of a treatment effect is due to the high prior odds of treatment effect and the high likelihood ratio for prostaglandin producing such an effect. If data is available, similar calculations can be used for other percentage decreases, other medications and for the monocular trial.

  5. Intraoffice variability of corneal biomechanical parameters and intraocular pressure (IOP).

    Science.gov (United States)

    González-Méijome, José M; Queirós, António; Jorge, Jorge; Díaz-Rey, Alberto; Parafita, Manuel A

    2008-06-01

    To evaluate the intraoffice hour variability of intraocular pressure (IOP) and in vivo biomechanical properties of the cornea, as measured with the Ocular Response Analyzer (ORA). The right eye of each of 58 young healthy subjects (14 men, 44 women) was measured at 1-hour intervals from 9.00 a.m. until 7.00 p.m. with the ORA. Subjects' age ranged from 19 to 45 years (average +/- standard deviation, 25 +/- 6 years). Average intraoffice hour variability of IOP and corneal biomechanical parameters were not statistically significant, showing a stable profile during the hours of the day studied. An interesting finding was that although there were no significant diurnal variations in any of the parameters, minor changes in corneal-compensated IOP and a Goldmann-equivalent IOP were significantly correlated with the intraoffice hour variability of corneal biomechanical parameters corneal hysteresis (CH) and the corneal resistance factor (CRF). Corneal-compensated IOP changes were the most strongly associated with intraoffice hour variability in CH for all measurement times (r = 0.598; p biomechanical behavior of the cornea against the mechanical stimuli used by current non-contact tonometers. The most stable period to measure IOP and biomechanical parameters with ORA was in the afternoon.

  6. Correlations between corneal hysteresis, intraocular pressure, and corneal central pachymetry.

    Science.gov (United States)

    Touboul, David; Roberts, Cynthia; Kérautret, Julien; Garra, Caroline; Maurice-Tison, Sylvie; Saubusse, Elodie; Colin, Joseph

    2008-04-01

    To analyze the correlation between corneal hysteresis (CH) measured with the Ocular Response Analyzer (ORA, Reichert) and ultrasonic corneal central thickness (CCT US) and intraocular pressure measured with Goldmann applanation tonometry (IOP GA). Bordeaux 2 University, Ophthalmology Department, Bordeaux, France. This study comprised 498 eyes of 258 patients. Corneal hysteresis, corneal resistance factor (CRF), and IOP corneal-compensated (IOPcc) were provided by the ORA device; CCT US and IOP GA were also measured in each eye. The study population was divided into 5 groups: normal (n = 122), glaucoma (n = 159), keratoconus (n = 88), laser in situ keratomileusis (LASIK) (n = 78), and photorefractive keratectomy (n = 39). The Pearson correlation was used for statistical analysis. Corneal hysteresis was not strongly correlated with IOP or CCT US. The mean CH in the LASIK (8.87 mm Hg) and keratoconus (8.34 mm Hg) groups was lower than in the glaucoma (9.48 mm Hg) and normal (10.26 mm Hg) groups. The lower the CH, the lower its correlation with IOPcc and IOP GA. A CH higher than the CRF was significantly associated with the keratoconus and post-LASIK groups. Corneal hysteresis, a new corneal parameter, had a moderate dependence on IOP and CCT US. Weaker corneas could be screened with ORA parameters, and low CH could be considered a risk factor for underestimation of IOP. The CCT US should continue to be considered a useful parameter.

  7. Aerobic exercise and intraocular pressure in normotensive and glaucoma patients

    Directory of Open Access Journals (Sweden)

    Chatzibalis Theodosios

    2009-08-01

    Full Text Available Abstract Background With the increasing number of people participating in physical aerobic exercise, jogging in particular, we considered that it would be worth knowing if there are should be limits to the exercise with regard to the intraocular pressure (IOP of the eyes. The purpose of this study is to check IOP in healthy and primary glaucoma patients after aerobic exercise. Methods 145 individuals were subdivided into seven groups: normotensives who exercised regularly (Group A; normotensives in whose right eye (RE timolol maleate 0.5% (Group B, latanoprost 0.005% (Group C, or brimonidine tartrate 0.2% (Group D was instilled; and primary glaucoma patients under monotherapy with β-blockers (Group E, prostaglandin analogues (Group F or combined antiglaucoma treatment (Group G instilled in both eyes. The IOP of both eyes was measured before and after exercise. Results A statistically significant decrease was found in IOP during jogging. The aerobic exercise reduces the IOP in those eyes where a b-blocker, a prostaglandin analogue or an α-agonist was previously instilled. The IOP is also decreased in glaucoma patients who are already under antiglaucoma treatment. Conclusion There is no ocular restriction for simple glaucoma patients in performing aerobic physical activity.

  8. Effects of fasting on intraocular pressure in a black population.

    Science.gov (United States)

    Hassan, Mustapha B; Isawumi, Michaeline A

    2014-01-01

    There is a dearth of literature available on the effects of fasting on Intraocular pressure (IOP) among all races and worldwide. To determine the effects of fasting on IOP in a black African population. A population-based survey utilizing multistage random sampling techniques was carried out among healthy adult Muslims who were examined before and during Ramadan fast in Osogbo, Nigeria. Demographics were obtained, visual acuities, clinical examination of both eyes, and IOPs were done. Weights and waist circumference were measured. Data were analyzed using Statistical Package for Social Sciences ( SPSS) Version 16. Analysis generated frequencies and cross tabulations, whereas statistical significant values were derived using paired sample t-test and P fasting, the mean weights were 65.92 kg SD 12.98 and 65.29 kg SD 12.41 with a reduction of 0.63 kg SD 3.82 (P = 0.214, 95% confidence interval (CI): 0.372-1.626); and the mean waist circumference was 87.20 cm SD 12.39 and 81.78 cm SD 11.65 (P = 0.000, 95% CI 4.128-6.720), respectively. Mean IOPs were 15.98 mmHg SD 3.11 and 14.08 mmHg SD 2.71 before and during fasting, respectively (P = 0.000, 95% CI 0.98558-2.82798). The study shows that fasting significantly reduced IOP in an ocularly healthy black African population.

  9. Calcium channels and their blockers in intraocular pressure and glaucoma.

    Science.gov (United States)

    Mayama, Chihiro

    2014-09-15

    Several factors besides high intraocular pressure assumed to be associated with the development and progression of glaucoma, and calcium channel blockers (CCBs) have been an anticipated option for glaucoma treatment by improving ocular perfusion and/or exerting neuroprotective effects on retinal ganglion cells with safety established in wide and long-term usage. Decrease in IOP has been reported after topical application of CCBs, however, the effect is much smaller and almost negligible after systemic application. Various CCBs have been reported to increase posterior ocular blood flow in vivo and to exert direct neuroprotection in neurons in vitro. Distribution of the drug at a pharmacologically active concentration in the posterior ocular tissues across the blood-brain barrier or blood-retina barrier, especially in the optic nerve head and retina where the ganglion cells mainly suffer from glaucomatous damage, is essential for clinical treatment of glaucoma. Improved visual functions such as sensitivity in the visual field test have been reported after administration of CCBs, but evidences from the randomized studies have been limited and effects of CCBs on blood flow and direct neuroprotection are hardly distinguished from each other. © 2013 Published by Elsevier B.V.

  10. Intraocular pressure fluctuation during microincision vitrectomy with constellation vision system.

    Science.gov (United States)

    Sugiura, Yoshimi; Okamoto, Fumiki; Okamoto, Yoshifumi; Hiraoka, Takahiro; Oshika, Tetsuro

    2013-11-01

    To investigate intraocular pressure (IOP) fluctuation during various vitrectomy maneuvers using the vitrectomy system (Alcon Constellation Vision System). An experimental study as laboratory investigation. In porcine eyes, 23- and 25-gauge vitrectomy was performed, and IOP fluctuations were evaluated in vitreous cutting mode, in aspiration mode, and during scleral compression. The measurements were performed with the IOP control setting turned on or off. Using the 23-gauge system with the IOP control setting turned on, IOP decreased from 30 to 23.7 mm Hg after starting vitreous cutting, and then returned to 30 mm Hg in 2.6 seconds. When the IOP control setting was turned off, IOP decreased to 19.1 mm Hg in 0.9 seconds, and remained at that pressure. Under aspiration at 650 mm Hg without cutting, IOP showed a sharp depression from 30 to 12.2 mm Hg, and then returned to 30.6 mm Hg in 2.6 seconds with the IOP control setting turned on. When the IOP control setting was turned off, IOP decreased to 2.2 mm Hg in 9.7 seconds, and did not recover. When the sclera was compressed without aspiration, IOP rapidly increased to 70-100 mm Hg, and then slowly decreased to 30 mm Hg in 3.5-4.0 seconds, with or without the IOP control system. Similar data were obtained with 25-gauge vitrectomy. The IOP control system can attenuate IOP fluctuations during vitrectomy maneuvers. There was no significant difference in IOP fluctuations between 23- and 25-gauge systems. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Evaluation of the diurnal intraocular pressure fluctuations and blood pressure under dehydration due to fasting

    Directory of Open Access Journals (Sweden)

    Gonen Baser

    2016-12-01

    Full Text Available Introduction: This study aimed to investigate the diurnal intraocular pressure fluctuations under dehydration conditions and the relationship between the intraocular pressure fluctuations and blood pressure. Methods: The intraocular pressures (IOP, body weights, as well as systolic and diastolic blood pressures (SBP, DBP of 36 fasting healthy volunteers were recorded at 8:00 a.m. and 5:00 p.m. in the Ramadan of 2014 and two weeks after it. The data were analyzed using paired Student’s t-test and Pearson correlation analysis. Results: As the results demonstrated, the mean diurnal IOP differences of IOP, SBP, DBP, and weight were 2.67±1.33 mmHg, 9.44±8.02 mmHg, 3.33±5.94 mmHg, and 0.90±0.46 kg during the fasting period, respectively. In addition, the mean diurnal IOP differences of IOP, SBP, DBP, and weight were -0.33±1.4 mmHg (P=0.001, 0.55±7.25mmHg (P=0.003, -3.33±5.94 mmHg (P=0.001, and 0.12±0.45 kg (P=0.001 during the control period, respectively. There was a moderate correlation between the diurnal IOP and SBP differences (r=0.517, P=0.028. Conclusion: Based on the findings of the current study, the total fluid volume might have a more dominant effect on IOP peaks than the sympathetic system activity. Furthermore, the SBP was found to correlate with the IOP.

  12. Risk factors for intraocular pressure rise following phacoemulsification

    Directory of Open Access Journals (Sweden)

    Muge Coban-Karatas

    2013-01-01

    Full Text Available Purpose: This study was designed to analyze the risk factors resulting in high intraocular pressure (IOP, which was accepted as IOP higher than 22 mmHg, following uncomplicated phacoemulsification. Materials and Methods: The records of 812 eyes of 584 patients who underwent uncomplicated phacoemulsification were evaluated. There were 330 men and 254 women ranging between the age of 26 and 89 years (65.4 ± 9.8 years. The preoperative, postoperative first day (day 1, first week (day 7, and first month (day 30 IOP values were analyzed. Data on history of diabetes, glaucoma, pseudoexfoliation (PXF, incision site, capsular staining with trypan blue, and surgeon were recorded. A multinomial regression analysis was performed to analyse the relationship of the factors with postoperative high IOP. Results: The mean IOP was 15.6 ± 4.3 mmHg preoperatively. Postoperatively that were changed to 19.7 ± 9.0 mmHg at day 1, 12.7 ± 4.5 mmHg at day 7, and 12.8 ± 3.7 mmHg at day 30. The factors such as surgeon, presence of PXF, diabetes, surgical incision site, and trypan blue were not related to the postoperative high IOP (P > 0.05, in all. The only factor that related to high IOP at all visits was glaucoma (P < 0.005. Conclusion: According to our results, preoperative diagnosis of glaucoma seems to be the only factor to affect the postoperative IOP higher than 22 mmHg.

  13. Lens parameters as predictors of intraocular pressure changes after phacoemulsification.

    Science.gov (United States)

    Moghimi, S; Abdi, F; Latifi, G; Fakhraie, G; Ramezani, F; He, M; Lin, S C

    2015-11-01

    To evaluate intraocular pressure (IOP) change after cataract surgery in non-glaucomatous eyes with narrow and open angles (OAs) and its relation to novel lens parameters measured by anterior segment optical coherence tomography (AS-OCT). University affiliated hospital, Farabi Eye Hospital, Tehran, Iran. Prospective interventional case series. In this prospective study, 85 non-glaucomatous eyes underwent phacoemulsification and lens implantation. Thirty-nine eyes had OAs and 46 eyes had narrow angles (NAs). IOP and biometric parameters were measured by AS-OCT preoperatively and 3 months after surgery. Change in IOP and its relation to biometric parameters, including lens vault (LV), anterior vault (AV), defined as the sum of the LV and the ACD, and relative LV (rLV), defined as the ratio of the LV to the AV, were evaluated. The main outcome measure was degree of IOP change after phacoemulsification. Of the 85 patients included in the analysis, 35 were male and 50 were female with an overall mean age of 62.2 ± 8.9 years. The average IOP reduction was -4.95 ± 2.26 mm Hg, from a preoperative mean of 17.12 ± 2.47 mm Hg, at 3 months after cataract surgery. The amount of IOP reduction was significantly greater in the NA compared with the OA group. In multivariate linear regression analysis, preoperative IOP and AV were significantly associated with IOP decrease (all ≤ 0.03). Cataract surgery results in IOP reduction in both OA and NA eyes. The amount of IOP reduction is related to AV.

  14. Corneal biomechanical properties and intraocular pressure measurement in Marfan patients.

    Science.gov (United States)

    Kara, Necip; Bozkurt, Ercument; Baz, Okkes; Altinkaynak, Hasan; Dundar, Huseyin; Yuksel, Kemal; Yazici, Ahmet Taylan; Demirok, Ahmet; Candan, Sukru

    2012-02-01

    To compare the biomechanical properties of the cornea and intraocular pressure (IOP) between patients with Marfan syndrome and age-matched controls. Departments of Ophthalmology and Genetics, Bakirkoy Maternity and Children Diseases Hospital, and Beyoglu Eye Education and Research Hospital, Istanbul, Turkey. Cross-sectional study. This study comprised patients with Marfan syndrome (study group) and healthy individuals (control group). The study group was subdivided into patients with ectopia lentis and patients without ectopia lentis. In the right eye of each patient, the corneal hysteresis (CH), corneal resistance factor (CRF), Goldman-correlated IOP, and corneal-compensated IOP were recorded. Overall, the mean CH, CRF, Goldman-correlated IOP, and corneal-compensated IOP were not significantly different between the study group and the control group. The mean CH was 9.9 mm Hg ± 1.2 (SD) in study eyes with ectopia lentis and 11.2 ± 1.5 mm Hg in study eyes without ectopia lentis (P=.016); the mean CRF was 8.2 ± 1.8 mm Hg and 11.3 ± 1.9 mm Hg, respectively (P<.001). The mean Goldman-correlated IOP was 11.7 ± 2.7 mm Hg in study eyes with ectopia lentis and 16.2 ± 4.3 in study eyes without ectopia lentis (P=.003); the mean corneal-compensated IOP was 13.5 ± 4.1 mm Hg and 15.6 ± 3.8 mm Hg, respectively (P=.07). The CH, CRF, and Goldman-correlated IOP were significantly lower in the Marfan syndrome eyes with ectopia lentis than in the Marfan syndrome eyes without ectopia lentis. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  15. Changes in intraocular pressure after pharmacologic pupil dilation

    Directory of Open Access Journals (Sweden)

    Kim Joon

    2012-09-01

    Full Text Available Abstract Background Intraocular pressure (IOP may vary according to the change of ocular conditions. In this study, we want to assess the effect and mechanism of pupil dilation on IOP in normal subjects. Methods We prospectively evaluated 32 eyes of 32 patients (age; 61.7 ± 8.2 years with normal open angles under diurnal IOP. IOP was measured every two hours from 9 AM to 11 PM for one day to establish baseline values and was measured again for one day to assess the differences after dilation. To induce dilation, we administered 2.5% phenylephrine and 1% tropicamide every 5 minutes from 8:30 AM to 8:45 AM and for every two hours from 11 AM to 9 PM to keep the pupil dilated. Diurnal IOP, biometry, Visante OCT, and laser flare photometry were measured before and after dilation. Results We observed a significant increase in IOP after dilation, 1.85 ± 2.01 mmHg (p = 0.002. IOP elevation remained significant until about four hours after dilation. Thereafter, IOP decreased slowly and eventually reached pre-dilation level (p > 0.05. Flare values decreased, and the anterior chamber angle became wider after mydriasis. Conclusions Dilation of the pupil significantly and incidentally elevated IOP in normal subjects. Further related studies are warranted to characterize the mechanism of the increased IOP after dilation.

  16. Fluctuations in Intraocular Pressure Increase the Trabecular Meshwork Extracellular Matrix

    Directory of Open Access Journals (Sweden)

    Huan Zou

    2014-04-01

    Full Text Available Background/Aims: The trabecular meshwork (TM tissue is constantly exposed to dynamic stress caused by intraocular pressure (IOP. The effects of such biomechanical stress on the TM have not been analyzed. This study developed an animal model of fluctuating IOP and evaluated the effects of these fluctuations on TM tissue. Methods: To create fluctuation in the IOP, one eye of adult SD rats was exposed to cyclic stress with IOP fluctuation ranging from 5 mmHg to 45 mmHg at a 1/60 Hz frequency for 30 minutes every day for several weeks. The other eye was not treated and served as the control. Hematoxylin-eosin staining was used to evaluate changes in the ganglion cells and the morphology, thickness and density of the TM; immunohistochemistry was used to detect α-smooth muscle actin (α-SMA, laminin (LA and fibronectin (FN expression in the TM. Results: After several weeks of daily IOP fluctuation, the TM thickness remained unchanged, whereas the density dramatically increased. α-SMA, LA and FN were expressed in rat TM tissue, and the percentages of areas with positive expression significantly increased. The IOP was similar in the treated and control eyes and only tended to increase on day 22 of the experiment. Throughout the 28-day experiment, no ganglion cells were lost. Conclusions: Large fluctuations in IOP promoted the synthesis of α-SMA, LA and FN in the TM and increased the density of the TM, suggesting that fluctuations in IOP can induce pathological changes in the TM.

  17. Apparatus and method for non-contact, acoustic resonance determination of intraocular pressure

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Dipen N. (Los Alamos, NM); Wray, William O. (Los Alamos, NM)

    1994-01-01

    Apparatus and method for measuring intraocular pressure changes in an eye under investigation by detection of vibrational resonances therein. An ultrasonic transducer operating at its resonant frequency is amplitude modulated and swept over a range of audio frequencies in which human eyes will resonate. The output therefrom is focused onto the eye under investigation, and the resonant vibrations of the eye observed using a fiber-optic reflection vibration sensor. Since the resonant frequency of the eye is dependent on the pressure therein, changes in intraocular pressure may readily be determined after a baseline pressure is established.

  18. Apparatus and method for non-contact, acoustic resonance determination of intraocular pressure

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, D.N.; Wray, W.O.

    1994-12-27

    The apparatus and method for measuring intraocular pressure changes in an eye under investigation by detection of vibrational resonances therein. An ultrasonic transducer operating at its resonant frequency is amplitude modulated and swept over a range of audio frequencies in which human eyes will resonate. The output therefrom is focused onto the eye under investigation, and the resonant vibrations of the eye observed using a fiber-optic reflection vibration sensor. Since the resonant frequency of the eye is dependent on the pressure therein, changes in intraocular pressure may readily be determined after a baseline pressure is established. 3 figures.

  19. Elevated Intraocular Pressure due to Arteriovenous Fistula between External Carotid Artery and Facial Vein.

    Science.gov (United States)

    Cagatay, Halil Huseyin; Ekinci, Metin; Sendul, Selam Yekta; Uslu, Ceylan; Demir, Mehmet; Ulusay, Sıtkı Mert; Uysal, Ender; Seker, Selma

    2014-01-01

    Aqueous outflow via the conventional outflow pathway is dependent on the pressure gradient between intraocular pressure (IOP) and episcleral venous pressure (EVP). Elevated IOP resulting from increased EVP is a well-known complication of arteriovenous fistulas, which are usually between the carotid artery and the cavernous sinus. Arteriovenous malformations usually occur spontaneously, after a trauma or from iatrogenic causes, and they manifest with findings of chemosis, dilatation of the conjunctival vessels, exophthalmos, and extraocular motility limitation. In this study, we present a case of elevated IOP due to facial arteriovenous malformations following a functional neck dissection surgery that caused intraocular pressure elevation.

  20. Elevated Intraocular Pressure due to Arteriovenous Fistula between External Carotid Artery and Facial Vein

    Directory of Open Access Journals (Sweden)

    Halil Huseyin Cagatay

    2014-01-01

    Full Text Available Aqueous outflow via the conventional outflow pathway is dependent on the pressure gradient between intraocular pressure (IOP and episcleral venous pressure (EVP. Elevated IOP resulting from increased EVP is a well-known complication of arteriovenous fistulas, which are usually between the carotid artery and the cavernous sinus. Arteriovenous malformations usually occur spontaneously, after a trauma or from iatrogenic causes, and they manifest with findings of chemosis, dilatation of the conjunctival vessels, exophthalmos, and extraocular motility limitation. In this study, we present a case of elevated IOP due to facial arteriovenous malformations following a functional neck dissection surgery that caused intraocular pressure elevation.

  1. Cognitive brain responses during circadian wake-promotion: evidence for sleep-pressure-dependent hypothalamic activations.

    Science.gov (United States)

    Reichert, Carolin F; Maire, Micheline; Gabel, Virginie; Viola, Antoine U; Götz, Thomas; Scheffler, Klaus; Klarhöfer, Markus; Berthomier, Christian; Strobel, Werner; Phillips, Christophe; Salmon, Eric; Cajochen, Christian; Schmidt, Christina

    2017-07-17

    The two-process model of sleep-wake regulation posits that sleep-wake-dependent homeostatic processes interact with the circadian timing system to affect human behavior. The circadian timing system is fundamental to maintaining stable cognitive performance, as it counteracts growing homeostatic sleep pressure during daytime. Using magnetic resonance imaging, we explored brain responses underlying working memory performance during the time of maximal circadian wake-promotion under varying sleep pressure conditions. Circadian wake-promoting strength was derived from the ability to sleep during an evening nap. Hypothalamic BOLD activity was positively linked to circadian wake-promoting strength under normal, but not under disproportionally high or low sleep pressure levels. Furthermore, higher hypothalamic activity under normal sleep pressure levels predicted better performance under sleep loss. Our results reappraise the two-process model by revealing a homeostatic-dose-dependent association between circadian wake-promotion and cognition-related hypothalamic activity.

  2. Acute effects of consumption of energy drinks on intraocular pressure and blood pressure

    Directory of Open Access Journals (Sweden)

    Ilechie AA

    2011-04-01

    Full Text Available A Alex Ilechie, Sandra TettehDepartment of Optometry, University of Cape Coast, GhanaBackground: Energy drinks contain a wide variety of ingredients including caffeine, for which there have been conflicting reports regarding its effects on intraocular pressure (IOP and blood pressure. The aim of this study was to investigate the acute effects of an energy drink (Red Bull® on the IOP and blood pressure of healthy young adults.Methods: Thirty healthy university students of either gender, aged 18–30 (mean 23.20 ± 2.81 years were randomly selected to participate in this study. The subjects were randomly divided into two groups (experimental and control and were asked to abstain from caffeine for 48 hours prior to and during the study. Baseline IOP and blood pressure were measured. The experimental group (n = 15 consumed one can of the energy drink (containing 85 mg of caffeine in 250 mL and measurements were repeated at 30, 60, and 90 minutes, while the control group drank 250 mL of water and were tested over the same time period.Results: When compared with baseline, a significant decrease (P < 0.05 in mean IOP at 60 and 90 minutes was observed in the experimental group. There was no corresponding change in systolic or diastolic blood pressure.Conclusion: Our results suggest that energy drinks (ie, Red Bull produce a significant reduction in IOP but have no effect on blood pressure. These findings may be interpreted as reflecting the effect of the combination of caffeine and taurine in the Red Bull energy drink. This effect may result from the known hypotensive effect of taurine, and warrants further study.Keywords: acute effect, intraocular pressure, blood pressure, glaucoma, caffeine, taurine

  3. The Effect of Phacoemulsification with Posterior Chamber Intraocular Lens Implantation on Intraocular Pressure and Anterior Chamber Depth

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Mohamadi

    2013-12-01

    Full Text Available Purpose: To evaluate intraocular pressure (IOP and anterior chamber depth (ACD change after phacoemulsification with posterior chamber intraocular lens implantation Methods: In this quasi-experimental study, 84 patients with senile cataract were included. All patients had normal IOP. Patients with traumatic and complicated cataract, any history of uveitis, glaucoma, or other ocular disease or surgery were excluded. Patients underwent phacoemulsification and intraocular lens implantation by the same surgeon. IOP, ACD, and lens thickness were measured and recorded before surgery. IOP was measured at 4, 8 and 12 postoperative weeks and ACD was measured 12 weeks after surgery. Results: The mean preoperative ACD significantly increased from 2.93 mm to 3.54 mm postoperatively (p<0.0001. Mean preoperative IOP was 16.06 mmHg which decreased to 12.01 IOP mmHg, 12.57 mmHg and 12.90 mmHg at 4 weeks, 8 weeks and 12 weeks postoperatively, respectively (all p-values<0.0001. There was a correlation between lens thickness and changes of and ACD after the surgery. There was also a positive correlation between preoperative IOP and IOP reduction after the surgery. Conclusion: Phacoemulsification decreases IOP specially in eyes with higher preoperative IOP and thicker lenses.

  4. Intraocular pressure and glaucoma: Is physical exercise beneficial or a risk?

    Science.gov (United States)

    McMonnies, Charles William

    2016-01-01

    Intraocular pressure may become elevated with muscle exertion, changes in body position and increased respiratory volumes, especially when Valsalva manoeuver mechanisms are involved. All of these factors may be present during physical exercise, especially if hydration levels are increased. This review examines the evidence for intraocular pressure changes during and after physical exercise. Intraocular pressure elevation may result in a reduction in ocular perfusion pressure with the associated possibility of mechanical and/or ischaemic damage to the optic nerve head. A key consideration is the possibility that, rather than being beneficial for patients who are susceptible to glaucomatous pathology, any intraocular pressure elevation could be detrimental. Lower intraocular pressure after exercise may result from its elevation causing accelerated aqueous outflow during exercise. Also examined is the possibility that people who have lower frailty are more likely to exercise as well as less likely to have or develop glaucoma. Consequently, lower prevalence of glaucoma would be expected among people who exercise. The evidence base for this topic is deficient and would be greatly improved by the availability of tonometry assessment during dynamic exercise, more studies which control for hydration levels, and methods for assessing the potential general health benefits of exercise against any possibility of exacerbated glaucomatous pathology for individual patients who are susceptible to such changes. Copyright © 2015 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  5. Measurement of Intraocular Pressure by Patients With Glaucoma.

    Science.gov (United States)

    Pronin, Savva; Brown, Lyndsay; Megaw, Roly; Tatham, Andrew J

    2017-10-01

    The ability of patients to measure their own intraocular pressure (IOP) would allow more frequent measurements and better appreciation of peak IOP and IOP fluctuation. To examine whether patients with glaucoma can perform self-tonometry using a rebound tonometer and examine patient acceptability. An observational study in which IOP was assessed using Goldmann applanation tonometry and a rebound tonometer. Consecutive patients were provided with a patient information sheet and those consenting to take part in the study received standardized self-tonometry training and were then instructed to measure their own IOP under observation. This study was conducted at a glaucoma clinic at a university hospital from March 1, 2016, to December 30, 2016, and included both eyes of 100 patients with glaucoma or ocular hypertension. The percentage of patients who could successfully perform self-tonometry. Complete success was defined by a good technique and an IOP reading within 5 mm Hg of that obtained by a clinician using the same device. A 3-item questionnaire was used to examine perceptions of self-tonometry among patients. Among the 100 patients, the mean (SD) age was 67.5 (10.9) years (53% female). A total 73 of 100 patients (73%) met the complete success criteria. An additional 6 patients could use the device but had IOP readings greater than 5 mm Hg different from those obtained by the clinician. On average, IOP by the rebound tonometer was 2.66 mm Hg lower than Goldmann applanation tonometry (95% limits of agreement, -3.48 to 8.80 mm Hg). The IOPs with the rebound tonometer were similar whether obtained by self-tonometry or investigator, with excellent reproducibility with an intraclass correlation coefficient of 0.903 (95% CI, 0.867-0.928). A total of 56 of 79 successful or partially successful patients (71%) felt self-tonometry was easy, with 73 of 79 (92%) reporting self-tonometry to be comfortable, and a similar number happy to perform self-tonometry in the future

  6. Systemic Medication and Intraocular Pressure in a British Population

    Science.gov (United States)

    Khawaja, Anthony P.; Chan, Michelle P.Y.; Broadway, David C.; Garway-Heath, David F.; Luben, Robert; Yip, Jennifer L.Y.; Hayat, Shabina; Wareham, Nicholas J.; Khaw, Kay-Tee; Foster, Paul J.

    2014-01-01

    Objective To determine the association between systemic medication use and intraocular pressure (IOP) in a population of older British men and women. Design Population-based, cross-sectional study. Participants We included 7093 participants from the European Prospective Investigation into Cancer–Norfolk Eye Study. Exclusion criteria were a history of glaucoma therapy (medical, laser, or surgical), IOP asymmetry between eyes of >5 mmHg, and missing data for any covariables. The mean age of participants was 68 years (range, 48–92) and 56% were women. Methods We measured IOP using the Ocular Response Analyzer. Three readings were taken per eye and the best signal value of the Goldmann-correlated IOP value considered. Participants were asked to bring all their medications and related documentation to the health examination, and these were recorded by the research nurse using an electronic case record form. The medication classes examined were angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, α-blockers, β-blockers, calcium channel blockers, diuretics, nitrates, statins, insulin, biguanides, sulfonylureas, aspirin, and other nonsteroidal anti-inflammatory drugs. We examined associations between medication use and IOP using multivariable linear regression models adjusted for age, sex, and body mass index. Models containing diabetic medication were further adjusted for glycosylated hemoglobin levels. Main Outcome Measures Mean IOP of the right and left eyes. Results Use of systemic β-blockers (−0.92 mmHg; 95% CI, −1.19, −0.65; P<0.001) and nitrates (−0.63 mmHg; 95% CI, −1.12, −0.14; P = 0.011) were independently associated with lower IOP. The observed associations between statin or aspirin use with IOP were no longer significant after adjustment for β-blocker use. Conclusions This is the first population-based study to demonstrate and quantify clinically significant differences in IOP among participants using systemic

  7. Comparative evaluation of intraocular pressure changes subsequent to insertion of laryngeal mask airway and endotracheal tube.

    Directory of Open Access Journals (Sweden)

    Ghai B

    2001-07-01

    Full Text Available AIMS: To evaluate the intraocular pressure and haemodynamic changes subsequent to insertion of laryngeal mask airway and endotracheal tube. SUBJECTS AND METHODS: The study was conducted in 50 adult patients. A standard general anaesthesia was administered to all the patients. After 3 minutes of induction of anaesthesia baseline measurements of heart rate, non-invasive blood pressure and intraocular pressure were taken following which patients were divided into two groups: laryngeal mask airway was inserted in group 1 and tracheal tube in group 2. These measurements were repeated at 15-30 second, every minute thereafter up to 5 minutes after airway instrumentation. RESULTS: A statistically significant rise in heart rate, systolic blood pressure, diastolic blood pressure and intraocular pressure was seen in both the groups subsequent to insertion of laryngeal mask airway or endotracheal tube. Mean maximum increase was statistically more after endotracheal intubation than after laryngeal mask airway insertion. The duration of statistically significant pressure responses was also longer after endotracheal intubation. CONCLUSION: Laryngeal mask airway is an acceptable alternative technique for ocular surgeries, offering advantages in terms of intraocular pressure and cardiovascular stability compared to tracheal intubation.

  8. Rollable and implantable intraocular pressure sensor for the continuous adaptive management of glaucoma.

    Science.gov (United States)

    Piffaretti, Filippo; Barrettino, Diego; Orsatti, Paolo; Leoni, Lorenzo; Stegmaier, Peter

    2013-01-01

    We designed and tested a new rollable and implantable medical device to directly and continuously measure intraocular pressure. Since high intraocular pressure is a leading risk factor for glaucoma, such a system could solve the difficulties encountered in the management of this condition. In fact, glaucoma is one among those pathologies that could most benefit of an adaptive patient-specific medicine device. The presented prototype was realized with standard industrial microelectronic technologies (Flip-Chip on Kapton flexible PCB) and off-the-shelf IC components. Detailed system description and measurements, obtained during in-vitro and laboratory characterizations, are reported.

  9. Etamsylate (Dicynone) reduces aqueous humor formation and intraocular pressure in rabbits.

    Science.gov (United States)

    Jozsa, M

    1983-01-01

    The rate of aqueous humor production (measured by the clearance of 125I-labeled albumin administered into the anterior chamber) and the intraocular pressure (measured via an electronic transducer) fell after subconjunctival infection of 37 mg (0.3 ml) of etamsylate (Dicynone) in rabbits. The differences between treated and untreated animals with respect to both variables were statistically significant. It is conjectured that the action of etamsylate in lowering intraocular pressure may be mediated at least in part by its reduction of aqueous humor formation.

  10. Tolerability of 24-hour intraocular pressure monitoring of a pressure-sensitive contact lens.

    Science.gov (United States)

    Lorenz, Katrin; Korb, Christina; Herzog, Nicola; Vetter, Jan M; Elflein, Heike; Keilani, Munir M; Pfeiffer, Norbert

    2013-01-01

    To investigate tolerability and safety of a new diagnostic device for 24-hour intraocular pressure monitoring in healthy subjects and age-matched glaucoma patients. Twenty healthy subjects (group 1) and 20 age-matched glaucoma patients (group 2) were included in this prospective, single-center, open, observational parallel group study. The SENSIMED Triggerfish Sensor is a soft disposable contact lens embedding a telemetry chip and strain gauge sensor for continuous intraocular pressure monitoring. The Sensor was placed in 1 eye for 24 hours. Tolerability was evaluated using a visual analog scale (range, 0 to 100; 0=no discomfort; 100=very severe discomfort). Safety parameters included best corrected visual acuity, pachymetry, epithelial defects, conjunctival erythema, and corneal topography. Mean age was 61.7 years in group 1 and 65.0 years in group 2. Nineteen healthy subjects and 19 glaucoma patients (95%) completed the 24-hour wearing period. Early discontinuation resulted from pain (n=1) or inappropriate fitting of the sensor due to steep corneal radii (n=1). Mean tolerability was 21.8 in group 1 (range, 7 to 67) and 26.8 in group 2 (range, 0 to 71). Corneal epithelial staining (Modified Oxford scale, grade 0 to 4) changed from 0.4 (group 1) and 1.0 (group 2) at baseline to 1.8 (group 1) and 2.8 (group 2) after monitoring. No statistically significant differences could be detected between both groups. This new pressure-sensitive contact lens is tolerable and safe over a 24-hour wearing period in healthy subjects and glaucoma patients. Both normals and glaucoma patients had a similar safety and tolerability profile.

  11. A noncontact intraocular pressure measurement device using a micro reflected air pressure sensor for the prediagnosis of glaucoma

    Science.gov (United States)

    Kim, Kyoung Hwan; Kim, Byeong Hee; Seo, Young Ho

    2012-03-01

    This study investigates a novel, portable tonometer using a micro reflected air pressure sensor for the prediagnosis of glaucoma. Because glaucoma progresses slowly and is not painful, glaucoma patients require a portable prediagnosis system to periodically measure intraocular pressure at home. Conventionally, intraocular pressure is measured by an air-puff tonometer whereby the cornea is deformed by a short pulse of air pressure and the magnitude of the corneal deformation is measured by optic systems such as a combination of laser- and photodiodes. In this study, a micro reflected air pressure sensor was designed, fabricated, and tested in order to measure the magnitude of corneal deformation without optic systems. In an experimental study, artificial eyes with different internal pressures were fabricated and these pressures were measured by the aforementioned system.

  12. Elevated Intraocular Pressure due to Arteriovenous Fistula between External Carotid Artery and Facial Vein

    OpenAIRE

    Halil Huseyin Cagatay; Metin Ekinci; Selam Yekta Sendul; Ceylan Uslu; Mehmet Demir; Sıtkı Mert Ulusay; Ender Uysal; Selma Şeker

    2014-01-01

    Aqueous outflow via the conventional outflow pathway is dependent on the pressure gradient between intraocular pressure (IOP) and episcleral venous pressure (EVP). Elevated IOP resulting from increased EVP is a well-known complication of arteriovenous fistulas, which are usually between the carotid artery and the cavernous sinus. Arteriovenous malformations usually occur spontaneously, after a trauma or from iatrogenic causes, and they manifest with findings of chemosis, dilatation of the con...

  13. Assessment of Intraocular and Systemic Vasculature Pressure Parameters in Simulated Microgravity with Thigh Cuff Countermeasure

    Science.gov (United States)

    Huang, Alex S.; Balasubramanian, Siva; Tepelus, Tudor; Sadda, Jaya; Sadda, Srinivas; Stenger, Michael B.; Lee, Stuart M. C.; Laurie, Steve S.; Liu, John; Macias, Brandon R.

    2017-01-01

    Changes in vision have been well documented among astronauts during and after long-duration space flight. One hypothesis is that the space flight induced headward fluid alters posterior ocular pressure and volume and may contribute to visual acuity decrements. Therefore, we evaluated venoconstrictive thigh cuffs as a potential countermeasure to the headward fluid shift-induced effects on intraocular pressure (IOP) and cephalic vascular pressure and volumes.

  14. [Fluctuation of intraocular pressure in 24-hour telemonitoring compared to tonometry during normal office hours].

    Science.gov (United States)

    Jürgens, C; Antal, S; Henrici, K; Grossjohann, R; Tost, F H

    2009-01-01

    Elevated intraocular pressure (IOP) is a clinically relevant factor in glaucoma progression. As a dynamic parameter the IOP depends on various internal and exogenic influencing factors. Therefore, we analysed intraindividual IOD variations between ambulant care and 24-h home-monitoring using self-tonometry. This study is based on paper-based glaucoma cards of 25 patients with primary open angle glaucoma. Additionally, all patients participated in a telemedical home-monitoring study with self-measurements of IOP and blood pressure stored in an electronic patient record. The glaucoma cards contained a total number of 409 IOP values with documentation periods from 0.5 to 10 years. In the teletonometry project all 25 patients were observed for 6 months with 1490 recorded IOP values. Statistical analysis was performed with SPSS software. Average IOP values for all 25 glaucoma patients were 16.3 +/- 2.9 mmHg for both eyes in glaucoma card documentation, whereas the electronic patient records showed IOP averages of 18.9 +/- 4.7 mmHg for right eyes and 18.2 +/- 4.4 mmHg for left eyes. Corresponding to the practice opening hours the glaucoma cards contained no IOP records from 12:00 pm to 01:30 pm as well as between 06:00 pm and 07:15 am. In these time periods 17 % of all IOP values recorded in 24-hour teletonometry were higher than 20 mmHg. However, statistical analysis and clinical evaluation of device parameters and measurement characteristics revealed sporadic measuring errors. The additional involvement of self-tonometry in telemedical 24-h home-monitoring is a feasible method to record and detect intraday IOP fluctuations. Compared to single IOP measurements documented in common paper-based glaucoma cards, the 24-h electronic patient record showed more frequent circadian IOP variations. As a result, self-tonometry and home-monitoring can be a useful link to fill the gap between singular ambulant IOP measurement and hospitalisation with 24-hour IOP profiles.

  15. Prevention of intraocular pressure elevation after argon laser trabeculoplasty in primary open angle glaucoma

    Directory of Open Access Journals (Sweden)

    Božić Marija

    2011-01-01

    Full Text Available Introduction. Argon laser trabeculoplasty (ALT is an intraocular pressure lowering method that is overall safe and powerful, but often complicated by transient postoperative intraocular pressure rises. In prevention of this complication, we frequently use two potent alpha-adrenergic agonists - brimonidine and apraclonidine. Objective. The aim of this study was to compare brimonidine 0.2% and apraclonidine 0.5% efficacy and safety in prevention of intraocular pressure elevation after ALT. Methods. This was a prospective, randomized, double-masked and comparative study. This study included 27 POAG patients, 15 received 0.2% brimonidine, and 12 received 0.5% apraclonidine before laser surgery (22 eyes in both groups. Intraocular pressure readings were taken 1, 2, 3, 24 hours and 7 days after ALT. Student’s t-test was used to analyze data between two groups, and χ2 test to compare data within groups. Value p less than 0.05 was considered statistically significant. Results. We found statistically significantly lower IOP in eyes that received 0.2% brimonidine at readings taken 1 hour after ALT (p=0.001. There were no statistically significant differences in other IOP readings between two groups. Conclusion. A single preoperative drop of brimonidine 0.2% had similar efficacy and safety as apraclonidine 0.5% in preventing transient IOP elevations after ALT.

  16. The tonometric sensor, a new device for the measurement of intraocular pressure

    NARCIS (Netherlands)

    Voorthuyzen, J.A.; den Besten, C.; Bergveld, Piet

    1989-01-01

    In this paper we present a new sensor for the measurement of intraocular pressure. We have applied the indentation principle, in which the eye is indented by exerting a force on it, while the size of the indented area is monitored. To measure the force we have used a commercial force sensor. The

  17. time effect of exercise on intraocular pressure in a Nigerian population

    African Journals Online (AJOL)

    Numerous international studies have indicated that several physiological changes can influence the intraocular pressure (IOP) of subjects. In order to assess visual health status through physiological changes, the effects of rest and exercise on IOP were investigated in a Nigerian community. The research involved 24 ...

  18. Effect of pegaptanib sodium 0.3 mg intravitreal injections (Macugen) in intraocular pressure

    DEFF Research Database (Denmark)

    Boyer, David S; Goldbaum, Mauro; Leys, Anita M

    2014-01-01

    OBJECTIVE: To assess the rate of pegaptanib-associated sustained intraocular pressure (IOP) elevation. METHODS: A posthoc analysis was conducted on all IOP measurements, except the immediate 30-min postinjection, from all subjects randomised to pegaptanib 0.3 mg or sham injections continuously in...

  19. Twenty-four-hour intraocular pressure patterns in a symptomatic patient after ab interno trabeculotomy surgery.

    Science.gov (United States)

    Mansouri, Kaweh; Medeiros, Felipe A; Weinreb, Robert N

    2014-01-01

    We report the results of repeated ambulatory continuous 24-hour intraocular pressure (IOP) monitoring with a contact lens sensor (CLS) in a glaucoma patient with ocular pain after ab interno trabeculotomy (Trabectome™) surgery. Our findings show that a combined prostaglandin-pilocarpine treatment reduced nighttime IOP peaks and relieved the patient's symptoms.

  20. Clinical analysis of modified trabeculectomy in glaucoma surgery with high elevated intraocular pressure

    Directory of Open Access Journals (Sweden)

    Cang-Xia Zhang

    2013-10-01

    Full Text Available AIM: To make a retrospective analysis of the clinical data of modified trabeculectomy in treating glaucoma surgery with high elevated intraocular pressure retrospectively and evaluate the effect of modified trabeculectomy.METHODS:One hundred acute angle-closure glaucoma patients(100 eyeswith persistent high intraocular pressure were divided into treatment group(45 eyesand control group(55 eyes. Patients in treatment group was treated with by trabeculectomy, while those in control group received modified trabeculectomy. The modified measures include stellate ganglion block preoperative, topical anesthesia and local anesthesia with 20g/L lidocaine cotton-piece, to make scleral flap with sclerotome, to release aqueous humor outflow slowly after paracentesis of anterior chamber, and using mydriatic and cycloplegic during and after surgery.RESULTS: The incidence of operation complicationin control group was lower than that in treatment group. The differences were statistically significant(Pt=9.1535, Pt=39.8010, Pt=11.3219, PCONCLUSION: The modified trabeculectomy applied in the treatment of glaucoma with persistent high intraocular pressure can not only save the visual function of connection part to a certain extent, but also reduce the incidence of serious complications. It can obtain better intraocular pressure, shorten the average hospitalization days, decrease the expenses and increase patients satisfaction.

  1. Thrombospondin-1 (TSP1)–Null and TSP2-Null Mice Exhibit Lower Intraocular Pressures

    OpenAIRE

    Haddadin, Ramez I.; Oh, Dong-Jin; Kang, Min Hyung; Villarreal, Guadalupe; Kang, Ja-Heon; Jin, Rui; Gong, Haiyan; Rhee, Douglas J.

    2012-01-01

    Thrombospondin-1 (TSP1) and TSP2 are matricellular proteins expressed in the trabecular meshwork. TSP1-null and TSP2-null mice have lower intraocular pressures than their wild-type counterparts. Aqueous humor turnover studies suggest that the mechanism is enhanced outflow resistance.

  2. Genes influencing circadian differences in blood pressure in hypertensive mice.

    Directory of Open Access Journals (Sweden)

    Francine Z Marques

    Full Text Available Essential hypertension is a common multifactorial heritable condition in which increased sympathetic outflow from the central nervous system is involved in the elevation in blood pressure (BP, as well as the exaggerated morning surge in BP that is a risk factor for myocardial infarction and stroke in hypertensive patients. The Schlager BPH/2J mouse is a genetic model of hypertension in which increased sympathetic outflow from the hypothalamus has an important etiological role in the elevation of BP. Schlager hypertensive mice exhibit a large variation in BP between the active and inactive periods of the day, and also show a morning surge in BP. To investigate the genes responsible for the circadian variation in BP in hypertension, hypothalamic tissue was collected from BPH/2J and normotensive BPN/3J mice at the 'peak' (n = 12 and 'trough' (n = 6 of diurnal BP. Using Affymetrix GeneChip® Mouse Gene 1.0 ST Arrays, validation by quantitative real-time PCR and a statistical method that adjusted for clock genes, we identified 212 hypothalamic genes whose expression differed between 'peak' and 'trough' BP in the hypertensive strain. These included genes with known roles in BP regulation, such as vasopressin, oxytocin and thyrotropin releasing hormone, as well as genes not recognized previously as regulators of BP, including chemokine (C-C motif ligand 19, hypocretin and zinc finger and BTB domain containing 16. Gene ontology analysis showed an enrichment of terms for inflammatory response, mitochondrial proton-transporting ATP synthase complex, structural constituent of ribosome, amongst others. In conclusion, we have identified genes whose expression differs between the peak and trough of 24-hour circadian BP in BPH/2J mice, pointing to mechanisms responsible for diurnal variation in BP. The findings may assist in the elucidation of the mechanism for the morning surge in BP in essential hypertension.

  3. Intraocular pressure-lowering effect of oral paracetamol and its in vitro corneal penetration properties

    Directory of Open Access Journals (Sweden)

    Mohamed N

    2013-01-01

    Full Text Available Nabiel Mohamed, David MeyerDivision of Ophthalmology, Faculty of Medicine and Health Sciences, University of Stellenbosch, Cape Town, South AfricaBackground: Several studies have confirmed the ability of cannabinoids to reduce intraocular pressure. Experimental data recently demonstrated unequivocally that the analgesic effect of paracetamol is due to its indirect action on cannabinoid receptors. The question then arises as to whether paracetamol can reduce intraocular pressure via its effect on intraocular cannabinoid receptors.Methods: A 2-week, prospective, randomized, controlled, single-center, parallel-group pilot study was carried out to determine the efficacy and safety of paracetamol 1 g orally administered every 6 hours in adult patients with primary or secondary open angle glaucoma as compared with topical levobunolol 0.5% twice a day. Patient well-being was closely monitored throughout the study and focused on hepatic safety in accordance with Drug-Induced Liver Injury Network criteria. The in vitro diffusion kinetics of acetaminophen in a phosphate-buffered solution in rabbit and human corneas was also investigated, with the view to a topical application.Results: Eighteen adult patients were enrolled in the study, with nine in the topical levobunolol group and nine in the oral paracetamol group. In the levobunolol group, the mean reduction in intraocular pressure at day 7 was 7.5 mmHg (P < 0.008 and at day 14 was 9.1 mmHg (P < 0.005, from a mean baseline intraocular pressure of 29.6 mmHg. The corresponding figures for the paracetamol group were 8.8 mmHg (P < 0.0004 at day 7 and 6.5 mmHg (P < 0.004 at day 14, from a mean baseline intraocular pressure of 29.4 mmHg. Both study regimens were well tolerated. No serious treatment-related adverse events were reported in either of the treatment groups. Liver function tests, systolic/diastolic blood pressure, or heart rate remained unchanged in both groups during the 2 weeks of the study. In

  4. Diurnal fluctuation of higher order ocular aberrations: correlation with intraocular pressure and corneal thickness.

    Science.gov (United States)

    Mierdel, Peter; Krinke, Hans-Eberhard; Pollack, Katharina; Spoerl, Eberhard

    2004-01-01

    Optimal wavefront-guided refractive corneal laser surgery requires sufficiently exact data of optical higher order aberrations. We investigated whether these aberrations had a systematic during-the-day variation, studied the range of variation, and changes in intraocular pressure and central corneal thickness. In 22 eyes of 22 young volunteers the optical aberrations of higher order were measured by means of a Tscherning-type ocular aberrometer three times during one day (7 AM, 12 noon, 4 PM). In addition, in 12 of these eyes the intraocular pressure and central corneal thickness were measured. The intraocular wavefront aberration was computed using Zernike polynomials up to the sixth order, and Zernike coefficients of third and fourth order were analyzed. Only the coefficient Z 2/4 (C13) showed a significant increase during the day by a mean 0.016 microm. A significant regression could be detected between changes of coefficients Z3/3, Z-2/4, Z0/4, Z4/4, and changes of intraocular pressure or central corneal thickness during the day. Due to the small values, the measured during-the-day changes of higher order aberrations had no direct practical consequences for the aberrometry-guided corneal laser surgery. Alterations of some Zernike coefficients during the day may be explained by the biomechanical behavior of the cornea.

  5. Meta-analysis of timolol on diurnal and nighttime intraocular pressure and blood pressure.

    LENUS (Irish Health Repository)

    Lee, Princeton Wen-Yuan

    2012-02-01

    PURPOSE: To evaluate the nighttime intraocular pressure (IOP) and blood pressure (BP) response to timolol treatment in patients with ocular hypertension or primary open-angle glaucoma. METHODS: This was a meta-analysis of previously published studies that must have been randomized, prospective, crossover or parallel, single or double-masked trials. The treatment period must have been >\\/=2 weeks with >\\/=19 patients per treatment arm for a crossover, and >\\/=50 patients for a parallel designed trial. Studies must have included both baseline and treated 24-hour curves. RESULTS: For the IOP analysis, we included 8 articles with 340 patients. A reduction from baseline was observed for timolol at each time point and for the 24-hour curve (p<\\/=0.009). When 2 studies, in which timolol was used adjunctively, were removed, a similar difference was observed as above at each time point and for the 24-hour curve (p<\\/=0.003). In 2 studies, there were small reductions from baseline for the mean diastolic and systolic BPs at most time points and for the 24-hour curve (3.9 and 4.2 mmHg, respectively) with timolol treatment. The ocular perfusion pressure did not show any difference between baseline and timolol treatment at any time point or for the 24-hour curve (p>0.05). CONCLUSIONS: This meta-analysis suggests that topical timolol therapy provides an ocular hypotensive effect over the 24-hour curve, including the nighttime hours, and while small reductions in the systolic and diastolic pressures occur, the ocular perfusion pressure is not altered over 24 hours.

  6. DIURNAL VARIATION IN THE CARDIOVASCULAR INDICES AND INTRAOCULAR PRESSURE

    OpenAIRE

    Patil, R.B.; B.R. Doddamani; Ehtesham Ali Farooqui, Mohammed

    2012-01-01

    Introduction: Intra ocular pressure is an essential entity in maintaining the structural and functional integrity of eye ball. It varies in regular cycle in the normal eye for 24hour.  In the present study, the diurnal variation of Heart rate, intra ocular pressure, systolic, diastolic, pulse and mean arterial pressures from 6AM to 6PM with every 2 hour interval was investigated. Methodology: The present study included 100 normal male healthy subjects from the Gulbarga city, recruited after ...

  7. The effects of cigarette smoking on intraocular pressure and arterial ...

    African Journals Online (AJOL)

    This study was designed to determine the effects of cigarette Smoking on intra ocular pressure and arterial blood pressure of normotensive young male adults. Fifty male students (who met the screening conditions and devoid of obvious ocular pathology and systemic diseases and nonsmokers) had their intra ocular ...

  8. Intraocular pressure and corneal biomechanics in Fuchs' endothelial dystrophy and after posterior lamellar keratoplasty.

    Science.gov (United States)

    Clemmensen, Kåre; Hjortdal, Jesper

    2014-06-01

      To evaluate the precision of techniques for measuring intraocular pressure (IOP) in corneas with presumably altered biomechanical properties.   Intraocular pressure was measured with a Goldmann applanation tonometer (GAT), ocular response analyzer (ORA) and dynamic contour tonometer (DCT) in 70 eyes. Thirty-five eyes were normal corneas, 18 eyes had Fuchs' endothelial dystrophy, and 17 eyes had undergone Descemet's stripping automated endothelial keratoplasty (DSAEK) surgery. Corneal hysteresis (CH), corneal resistance factor (CRF) as well as central corneal thickness (CCT) were recorded with the ORA.   The measured cornea-corrected IOP using ORA was significantly higher than GAT in all three groups (pkeratoplasty. GAT and DCT seem to measure IOP correctly in patients with Fuchs' endothelial dystrophy as well as after posterior lamellar keratoplasty. Corneal-corrected IOP as measured with the ORA appears to overestimate IOP in patients with Fuchs' endothelial dystrophy as well as after posterior lamellar keratoplasty. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by Blackwell Publishing Ltd.

  9. Intra-Ocular Pressure Measurement in a Patient with a Thin, Thick or Abnormal Cornea

    Science.gov (United States)

    Clement, Colin I.; Parker, Douglas G.A.; Goldberg, Ivan

    2016-01-01

    Accurate measurement of intra-ocular pressure is a fundamental component of the ocular examination. The most common method of measuring IOP is by Goldmann applanation tonometry, the accuracy of which is influenced by the thickness and biomechanical properties of the cornea. Algorithms devised to correct for corneal thickness to estimate IOP oversimplify the effects of corneal biomechanics. The viscous and elastic properties of the cornea influence IOP measurements in unpredictable ways, a finding borne out in studies of patients with inherently abnormal and surgically altered corneal biomechanics. Dynamic contour tonometry, rebound tonometry and the ocular response analyzer provide useful alternatives to GAT in patients with abnormal corneas, such as those who have undergone laser vision correction or keratoplasty. This article reviews the various methods of intra-ocular pressure measurement available to the clinician and the ways in which their utility is influenced by variations in corneal thickness and biomechanics. PMID:27014386

  10. Effect of caffeine on the intraocular pressure in patients with primary open angle glaucoma

    OpenAIRE

    Chandra P; Gaur A; Varma S

    2011-01-01

    Peeyush Chandra1, Ajit Gaur1, Shambhu Varma21Chandra Eye Research Institute, Allahabad, UP, India; 2Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, MD, USAPurpose: Coffee and tea are very common nonalcoholic beverages. However, their intake, particularly that of coffee, has been suggested to increase intraocular pressure (IOP) in patients with open angle glaucoma/ocular hypertension. The causative agent has been suggested to be their caff...

  11. Corneal biomechanical parameters and intraocular pressure: the effect of topical anesthesia.

    Science.gov (United States)

    Ogbuehi, Kelechi C

    2012-01-01

    The intraocular pressures and biomechanical parameters measured by the ocular response analyzer make the analyzer a useful tool for the diagnosis and management of anterior segment disease. This observational study was designed to investigate the effect of topical anesthesia on the parameters measured by the ocular response analyzer: corneal hysteresis, corneal resistance factor, Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc). Two sets of measurements were made for 78 eyes of 39 subjects, approximately 1 week apart. In session 1, each eye of each subject was randomized into one of three groups: polyvinyl alcohol (0.5%), tetracaine hydrochloride (0.5%), or oxybuprocaine hydrochloride (0.4%). In session 2, eyes that were in the polyvinyl alcohol group in session 1 were assigned to the tetracaine group, those in the tetracaine group in session 1 were assigned to oxybuprocaine group, and those in the oxybuprocaine group in session 1 were assigned to the polyvinyl alcohol group. For both sessions, each subject first had his or her central corneal thickness assessed with a specular microscope, followed by measurements of intraocular pressure and corneal biomechanical parameters with the Ocular Response Analyzer. All measurements were repeated for 2 minutes and 5 minutes following the instillation of either polyvinyl alcohol, tetracaine, or oxybuprocaine. The level of statistical significance was 0.05. Polyvinyl alcohol, tetracaine hydrochloride, and oxybuprocaine hydrochloride had no statistically significant (P > 0.05) effect on any of the biomechanical parameters of the cornea. There was no statistically significant effect on either IOPg (P > 0.05) or IOPcc (P > 0.05) 2 minutes after the eye drops were instilled in either session. Five minutes after the eye drops were instilled, polyvinyl alcohol showed no statistically significant effect on either IOPg (P > 0.05) or IOPcc (P > 0.05) in either session

  12. Twenty-four-hour intraocular pressure patterns in patients with thyroid eye disease

    OpenAIRE

    Parekh, AS; Mansouri, K; Weinreb, RN; Tafreshi, A.; Korn, BS; Kikkawa, DO

    2015-01-01

    © 2014 Royal Australian and New Zealand College of Ophthalmologists. To prospectively investigate the safety, tolerability and 24-h intraocular pressure (IOP) patterns in patients with thyroid eye disease (TED) using a contact lens sensor (CLS). Design: Prospective study. Participants: Ten patients with established TED. Methods: Ten eyes of 10 patients were prospectively evaluated in an ambulatory 24-h IOP monitoring session using the CLS (Sensimed AG, Lausanne, Switzerland). Patients pursued...

  13. Intraocular Pressure After 2 Hours of Small-Diameter Scleral Lens Wear.

    Science.gov (United States)

    Nau, Cherie B; Schornack, Muriel M; McLaren, Jay W; Sit, Arthur J

    2016-11-01

    Compression of episcleral veins or deformation of tissue in the Schlemm's canal beneath the landing zone of scleral lenses could elevate intraocular pressure (IOP). We examined the effect of 2 hr of small-diameter scleral lens wear on IOP. Twenty-nine participants, 29 ± 6 years old (mean ± SD) who experienced no history of eye disease or scleral lens wear, were included in the study. Each participant was fitted with a 15-mm Jupiter scleral lens on one eye (study eye). Intraocular pressure was measured in both eyes by pneumatonometry centrally on the cornea and peripherally on the sclera. The lens was then placed on one eye and was worn for 2 hr. Intraocular pressure was remeasured immediately after lens placement, at 1 and 2 hr of lens wear, and immediately after lens removal. Intraocular pressure after removal of the scleral lens was compared with IOP before placing the lens and to IOP in the control eye using paired t tests. Immediately after removing the scleral lens, mean central IOP in the study eye (13.9 ± 3.1 mm Hg) was not different from mean central IOP in the control eye (13.5 ± 2.2 mm Hg, P = 0.4) or in the same eye before lens wear (13.6 ± 1.9 mm Hg, P = 0.6). There were also no differences in IOP measured peripherally at 2 hr of lens wear (P = 0.8). Neophyte scleral lens wear of a 15-mm scleral lens for 2 hr does not increase IOP in healthy eyes.

  14. Reduction of intra-ocular pressure by ocular compression before combined peri- and retrobulbar block.

    Science.gov (United States)

    Kallio, H; Harju, M P; Ihanamäki, T; Vesti, E T; Kivelä, T

    2011-04-01

    The intra-ocular pressure immediately before glaucoma surgery can be raised. We wished to investigate if ocular compression for 20 min before a combined peri- and retrobulbar injection would result in a lower pressure after the block. Sixty consecutive patients scheduled for filtration surgery were randomly assigned to receive ocular compression using an external pressure device for 20 min before combined peri- and retrobulbar injection (intervention group, who also received compression after the block) or to a control group in whom pressure was applied only after the block was completed. The intra-ocular pressure was measured at baseline, after the 20-min pre-injection compression (intervention group), after injecting the block, and after the 10-min post-injection compression. The pressure did not differ between groups at baseline, after the block or after the post-injection compression. In the intervention group, the compression before the block reduced the median (IQR [range]) pressure from 21.0 (17.0-25.0 [12.0-40.0]) mmHg to 16.8 (12.5-22.5 [7.5-33.5]) mmHg (pintra-ocular pressure, but applying an additional compression for 20 min before injecting the block is not beneficial. © 2011 The Authors. Anaesthesia © 2011 The Association of Anaesthetists of Great Britain and Ireland.

  15. The influence of new beta-adrenolytics nebivolol and carvedilol on intraocular pressure and iris blood flow in rabbits

    OpenAIRE

    Szumny, Dorota; Szeląg, Adam

    2014-01-01

    Background The aim of this study was to assess the influence of propranolol, nebivolol, and carvedilol on intraocular pressure and blood flow in vessels of rabbit’s (New Zealand White) eyeball. Methods The study was carried out on New Zealand white rabbits. Intraocular pressure was measured with the applanation tonometer Möller–Wedel and Icare; blood flow was measured with Doppler Laser Blood Flow Monitor MBD3. Results Following a single administration into a conjunctival sac, all drugs decre...

  16. Smooth-muscle BMAL1 participates in blood pressure circadian rhythm regulation

    Science.gov (United States)

    Xie, Zhongwen; Su, Wen; Liu, Shu; Zhao, Guogang; Esser, Karyn; Schroder, Elizabeth A.; Lefta, Mellani; Stauss, Harald M.; Guo, Zhenheng; Gong, Ming Cui

    2014-01-01

    As the central pacemaker, the suprachiasmatic nucleus (SCN) has long been considered the primary regulator of blood pressure circadian rhythm; however, this dogma has been challenged by the discovery that each of the clock genes present in the SCN is also expressed and functions in peripheral tissues. The involvement and contribution of these peripheral clock genes in the circadian rhythm of blood pressure remains uncertain. Here, we demonstrate that selective deletion of the circadian clock transcriptional activator aryl hydrocarbon receptor nuclear translocator–like (Bmal1) from smooth muscle, but not from cardiomyocytes, compromised blood pressure circadian rhythm and decreased blood pressure without affecting SCN-controlled locomotor activity in murine models. In mesenteric arteries, BMAL1 bound to the promoter of and activated the transcription of Rho-kinase 2 (Rock2), and Bmal1 deletion abolished the time-of-day variations in response to agonist-induced vasoconstriction, myosin phosphorylation, and ROCK2 activation. Together, these data indicate that peripheral inputs contribute to the daily control of vasoconstriction and blood pressure and suggest that clock gene expression outside of the SCN should be further evaluated to elucidate pathogenic mechanisms of diseases involving blood pressure circadian rhythm disruption. PMID:25485682

  17. Corneal biomechanical parameters and intraocular pressure: the effect of topical anesthesia

    Directory of Open Access Journals (Sweden)

    Ogbuehi KC

    2012-06-01

    Full Text Available Kelechi C OgbuehiCornea Research Chair, Department of Optometry and Vision Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi ArabiaBackground: The intraocular pressures and biomechanical parameters measured by the ocular response analyzer make the analyzer a useful tool for the diagnosis and management of anterior segment disease. This observational study was designed to investigate the effect of topical anesthesia on the parameters measured by the ocular response analyzer: corneal hysteresis, corneal resistance factor, Goldmann-correlated intraocular pressure (IOPg, and corneal-compensated intraocular pressure (IOPcc.Methods: Two sets of measurements were made for 78 eyes of 39 subjects, approximately 1 week apart. In session 1, each eye of each subject was randomized into one of three groups: polyvinyl alcohol (0.5%, tetracaine hydrochloride (0.5%, or oxybuprocaine hydrochloride (0.4%. In session 2, eyes that were in the polyvinyl alcohol group in session 1 were assigned to the tetracaine group, those in the tetracaine group in session 1 were assigned to oxybuprocaine group, and those in the oxybuprocaine group in session 1 were assigned to the polyvinyl alcohol group. For both sessions, each subject first had his or her central corneal thickness assessed with a specular microscope, followed by measurements of intraocular pressure and corneal biomechanical parameters with the Ocular Response Analyzer. All measurements were repeated for 2 minutes and 5 minutes following the instillation of either polyvinyl alcohol, tetracaine, or oxybuprocaine. The level of statistical significance was 0.05.Results: Polyvinyl alcohol, tetracaine hydrochloride, and oxybuprocaine hydrochloride had no statistically significant (P > 0.05 effect on any of the biomechanical parameters of the cornea. There was no statistically significant effect on either IOPg (P > 0.05 or IOPcc (P > 0.05 2 minutes after the eye drops were instilled in

  18. Update on pseudoexfoliation syndrome pathogenesis and associations with intraocular pressure, glaucoma and systemic diseases.

    Science.gov (United States)

    Anastasopoulos, Eleftherios; Founti, Panayiota; Topouzis, Fotis

    2015-03-01

    Pseudoexfoliation (PEX) syndrome is a common age-related disorder affecting intraocular and extraocular tissues. This review focuses on recent publications related with the pathogenesis and associations of PEX syndrome with intraocular pressure (IOP), glaucoma and systemic diseases. In PEX tissues, expression of lysyl oxidase-like 1 (LOXL1) was found to be markedly dysregulated. This may adversely affect elastin metabolism and lead to elastotic alteration in tissues such as lamina cribrosa. There is increasing evidence that cellular stress conditions and low-grade chronic inflammatory processes are involved in the pathogenesis of PEX. Although there is an increased risk for glaucoma development in patients with PEX and ocular hypertension as compared with non-PEX patients with ocular hypertension, LOXL1 single nucleotide polymorphisms were not associated with intraocular pressure (IOP) differences. Lack of association of PEX with all-cause mortality or dementia has been reported recently. The association with vascular diseases is not consistent among different studies. Despite the high prevalence of the LOXL1 variants in the general population, a much lower proportion of the population develops PEX, suggesting that in addition to LOXL1, other genetic, epigenetic and environmental factors may contribute to the development of PEX. Also, LOXL1 cannot help to identify those with PEX at increased risk for glaucoma development. Increased risk for glaucoma development in PEX patients who present with increased IOP may be related to other factors beyond IOP, contributing to increased vulnerability of the optic nerve to glaucoma development in the presence of PEX.

  19. Effect of sildenafil citrate on intraocular pressure and blood pressure in human volunteers.

    Science.gov (United States)

    Gerometta, Rosana; Alvarez, Lawrence J; Candia, Oscar A

    2011-07-01

    Anecdotal reports have suggested that the vasodilator, sildenafil citrate, which evokes its effect via a select inhibition of PDE5, has the potential to increase intraocular pressure (IOP) in some individuals. An ocular hypertensive effect by sildenafil was also recently described in a sheep animal model. In contrast, clinical studies have not found a direct association between sildenafil ingestion (commonly consumed as Viagra) and changes in IOP. However, some such studies also reported no effects of sildenafil on systemic blood pressure (BP) at the time of the IOP determination. Given this surprising result, our purpose was to repeat a study in human volunteers in the city of Corrientes, Argentina to corroborate the effects of sildenafil on human IOP and systemic BP. For the present study, 9 healthy volunteers (male and female, 18-74 years old) were selected as subjects after ophthalmic and cardiovascular evaluation indicated that they exhibited normal parameters for their age. In a masked, placebo-controlled study, the subjects ingested 100 mg sildenafil citrate (provided as Vorst from Laboratorios Bernabo, Argentina) in one session, and a placebo on a second separate occasion. IOP was measured with a Goldman applanation tonometer by an ophthalmologist, and BP by a second physician, neither of whom witnessed the tablet ingestion by the volunteers, nor provided with information on the nature of the test compounds. A third individual administered the tablets. The average baseline IOP of this group of 9 was 13.1 ± 0.6 mm Hg. Subsequent to sildenafil ingestion, IOP increased by 26% to 16.5 ± 0.8 mm Hg 60 min later (P < 0.005, as paired data), and returned to control values within 2 h. Both systolic and diastolic BP were significantly reduced by sildenafil ingestion. At the point of maximal systemic hypotension (90 min), the systolic and diastolic pressures declined by 15% and 13%, respectively. No significant changes in IOP or BP were recorded after

  20. Prospective Comparative Analysis of 4 Different Intraocular Pressure Measurement Techniques and Their Effects on Pressure Readings.

    Science.gov (United States)

    Berk, Thomas A; Yang, Patrick T; Chan, Clara C

    2016-10-01

    To compare intraocular pressure (IOP) measurement using the Goldmann applanation tonometry (GAT) without fluorescein, with fluorescein strips, with fluorescein droplets, and IOP measurement with Tono-Pen Avia (TPA). This was a prospective comparative clinical analysis. It was performed in clinical practice. The study population consisted of 40 volunteer patients, 1 eye per patient. All patients who were 18 years and older having routine ophthalmological examination were eligible to participate. Active corneal abrasions and/or ulcers, previous glaucoma surgery, or prostheses interfering with GAT measurement were excluded. GAT IOP was measured first without fluorescein, then with fluorescein strip, then with fluorescein droplet, and finally with the TPA device. The main outcome measure was central corneal IOP. Mean±SD IOP measurements for GAT without fluorescein, with fluorescein strip, with fluorescein droplet, and for TPA groups were 12.65±3.01, 14.70±2.82, 15.78±2.64, and 16.33±3.08 mm Hg, respectively. Repeated-measures analysis of variance corrected with the Greenhouse-Geisser estimate ([Latin Small Letter Open E]=0.732) showed that measuring technique had a significant effect on IOP measurements (F2.20,85.59=34.66, Pmeasurement ranging from 5.89 mm Hg in the GAT with fluorescein strip versus droplet compared with 11.83 mm Hg in the GAT with fluorescein strip versus TPA comparison. IOP measurement technique significantly impacted the values obtained. The ophthalmologist should ensure consistent measurement technique to minimize variability when following patients.

  1. Intraocular pressure-lowering effects of commonly used fixed combination drugs with timolol in the management of primary open angle glaucoma

    Directory of Open Access Journals (Sweden)

    Murat Atabey Ozer

    2014-10-01

    Full Text Available AIM:To evaluate intraocular pressure (IOP-lowering effect and ocular tolerability of brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies in the management of primary open angle glaucoma.METHODS:Each drug was administered for two months, after which a circadian tonometric curve was recorded using a Goldmann applanation tonometer. Ocular discomfort (conjunctival hyperemia, burning or stinging, foreign body sensation, itching, ocular pain of each eye was assessed by the subject on a standardized ocular discomfort scale.RESULTS:Among the three study groups, there were no significant differences in the mean baseline IOP measurements, mean 2nd mo IOP measurements, and mean (% change of IOPs from baseline. Among the three study groups, there were no significant differences in the mean IOP measurements obtained at circadian tonometric curves at baseline and at two months controls. In sum brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies showed similar effects on IOP levels.CONCLUSION:Brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies showed similar lowering efficaties on IOP levels whereas there was no any difference between each other.

  2. Circadian Misalignment Increases C-Reactive Protein and Blood Pressure in Chronic Shift Workers.

    Science.gov (United States)

    Morris, Christopher J; Purvis, Taylor E; Mistretta, Joseph; Hu, Kun; Scheer, Frank A J L

    2017-04-01

    Shift work is a risk factor for inflammation, hypertension, and cardiovascular disease. This increased risk cannot be fully explained by classical risk factors. Shift workers' behavioral and environmental cycles are typically misaligned relative to their endogenous circadian system. However, there is little information on the impact of acute circadian misalignment on cardiovascular disease risk in shift workers, independent of differences in work stress, food quality, and other factors that are likely to differ between night and day shifts. Thus, our objectives were to determine the independent effect of circadian misalignment on 24-h high-sensitivity C-reactive protein (hs-CRP; a marker of systemic inflammation) and blood pressure levels-cardiovascular disease risk factors-in chronic shift workers. Chronic shift workers undertook two 3-day laboratory protocols that simulated night work, comprising 12-hour inverted behavioral and environmental cycles (circadian misalignment) or simulated day work (circadian alignment), using a randomized, crossover design. Circadian misalignment increased 24-h hs-CRP by 11% ( p shift workers. This may help explain the increased inflammation, hypertension, and cardiovascular disease risk in shift workers.

  3. Corneal biomechanical properties and intraocular pressure measurement in patients with nanophthalmos.

    Science.gov (United States)

    Altan, Cigdem; Kara, Necip; Baz, Okkes; Satana, Banu; Demirok, Ahmet; Yilmaz, Omer Faruk

    2012-06-01

    To compare the biomechanical properties of the cornea and intraocular pressure (IOP) between patients with nanophthalmos and age-matched controls. In this prospective, cross-sectional and comparative study, 27 eyes of 27 healthy individuals (control group) and 27 eyes of 27 patients with nanophthalmos (study group) were enrolled. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated intraocular pressure (IOPcc) and Goldmann correlated intraocular pressure (IOPg) were recorded for the right eye of each participant using Reichert Ocular Response Analyser measurements. Also, all participants in this study underwent a standardised ocular examination including IOP measurement with Goldmann applanation tonometry (IOP(GAT)), central corneal thickness and axial length (AL) assessments. Mean CH in the nanophthalmic eyes and in the control eyes were 13.3 ± 2.4 mm Hg and 11.6 ± 1.7 mm Hg, respectively (p=0.003); mean CRF values in the nanophthalmic and the control eyes were 13.2 ± 1.8 mm Hg and 11.4 ± 1.9 mm Hg, respectively (p=0.001). Mean IOP(GAT) was 15.2 ± 3.3 mm Hg in the nanophthalmic eyes and 13.4 ± 2.7 mm Hg in the control group (p=0.031); mean IOPg values for the nanophthalmic and the control groups were 17.1 ± 5.3 mm Hg and 14.7 ± 3.5 mm Hg, respectively (p=0.042). Mean IOPcc values in the nanophthalmic and the control group were 13.6 ± 6.1 mm Hg and 14.8 ± 3.2 mm Hg, respectively (p=0.365). The CH, CRF, IOPg and IOP(GAT) were significantly higher in the nanophthalmic eyes, whereas no significant differences in IOPcc were observed. These findings may be taken into account when measuring IOP values in patients with nanophthalmos.

  4. Effect of Eye Rubbing on Corneal Biomechanical Properties and Intraocular Pressure

    Directory of Open Access Journals (Sweden)

    Refik Oltulu

    2014-08-01

    Full Text Available Objectives: To determine whether corneal biomechanical properties and intraocular pressure (IOP are affected by eye rubbing. Materials and Methods: Healthy individuals, aged between 15 and 50 years, without any ocular pathological signs were included. Corneal biomechanical parameters, Goldmann-equivalent intraocular pressure (IOPg, corneal-compensated intraocular pressure (IOPcc, corneal resistance factor (CRF, and corneal hysteresis (CH values were measured using an ocular response analyzer (ORA. Measurements were taken at baseline and immediately after 30 seconds of eye rubbing. ORA parameters before and after eye rubbing were analyzed using student’s t test. A p-value less than 0.05 was considered statistically significant. Results: We included eighty-one eyes of 53 individuals with a mean age of 32±10.11(15-50 years. Before eye rubbing, the mean measurement values were as follows: CH 10.93±1.69 mmHg, CRF 10.82±1.78 mmHg, IOPg 15.76±3.18 mmHg, and IOPcc 15.74±2.69 mmHg. The mean values after eye rubbing were: CH 11.11±1.52 mmHg, CRF 10.54±1.56 mmHg, IOPg 14.32±3.10 mmHg, and IOPcc 14.20±2.77 mmHg. The decrease in CRF, IOPg, and IOPcc was statistically significant, while the change in CH was found to be statistically insignificant. Conclusion: CRF, IOPg, and IOPcc decreased significantly after eye rubbing and this should be considered before taking any ORA measurements and interpreting the results. (Turk J Ophthalmol 2014; 44: 268-71

  5. Effect of prophylactic intraocular pressure-lowering medication (brinzolamide on intraocular pressure after ranibizumab intravitreal injection: A case–control study

    Directory of Open Access Journals (Sweden)

    Shuang Song

    2016-01-01

    Full Text Available Purpose: To observe the effect of prophylactic intraocular pressure (IOP-lowering medication (brinzolamide on IOP after ranibizumab intravitreal injections (IVIs. Materials and Methods: This prospective case–control study included 352 eyes from 352 patients (1 eye per patient who were treated with ranibizumab intravitreal injection and divided randomly into two groups. Two hundred and three patients in control group only received the ranibizumab IVI, but 149 patients in case group received one drop of prophylactic intraocular brinzolamide preinjection. The IOP was measured by noncontact tonometer before injection, at 10, 30, 120 min and 1 day after injection in a sitting position. Results: The mean IOP measured before injection, at 10, 30, 120 min and 1 day after injection individually were 15.79 ± 2.21 mmHg, 19.33 ± 4.86 mmHg, 16.64 ± 2.93 mmHg, 16.17 ± 3.13 mmHg, and 15.07 ± 2.55 mmHg in case group and were 15.82 ± 2.57 mmHg, 21.34 ± 5.88 mmHg, 18.17 ± 4.06 mmHg, 17.59 ± 4.42 mmHg, and15.48 ± 2.92 mmHg in control group. Comparing two groups, the mean increase on IOP was statistically significant at 10, 30, 120 min postinjection (P < 0.05. Conclusions: IVI of ranibizumab causes a considerable short-term transient rise on IOP in most patients. The effect of prophylactic IOP-lowering medication on IOP after IVIs can be statistically significant from 10 min to 2 h after IVIs.

  6. The effect of long-term use of intranasal steroids on intraocular pressure

    OpenAIRE

    Şimşek A; Bayraktar C; Doğan S; Karataş M; Sarıkaya Y

    2016-01-01

    Ali Şimşek,1 Cem Bayraktar,2 Sedat Doğan,2 Mehmet Karataş,2 Yasin Sarıkaya2 1Department of Ophthalmology, 2Department of Otolaryngology Head and Neck Surgery, Adıyaman University Research and Education Hospital, Adıyaman, Turkey Abstract: Long-term use of topical nasal steroids (especially older generation steroids) has been shown to elevate intraocular pressure (IOP), but newer intranasal steroids are thought to have a minimal effect on IOP because of their low bioavailability. This...

  7. Etiology and Management of Raised Intraocular Pressure following Posterior Chamber Phakic Intraocular Lens Implantation in Myopic Eyes.

    Directory of Open Access Journals (Sweden)

    Sirisha Senthil

    Full Text Available To evaluate the etiology and management of elevated intraocular pressure (IOP following posterior chamber phakic implantable collamer lens (ICL surgery.Between 2009 and 2015, 638 eyes of 359 subjects with refractive myopia, underwent V4b and V4c (CentraFLOW model ICL implantation. Ocular hypertension (OHT was defined as IOP of ≥ 22 mm Hg on two separate occasions and elevated IOP with corresponding optic disc or visual field damage was defined as glaucoma.Elevated IOP ≥ 22 mm Hg was noted in 33 eyes of 30 subjects (33/638; 5.17%. Median age of subjects with raised IOP was 26 years (Inter quartile range (IQR:22, 29 and median refarctive error was -16 diopters (-19.5, -13. The median follow up was 7.8 months (IQR:0.3, 17.6 and median time for postoperative IOP rise was 12 days, (IQR:2, 24. The various etiologies for elevated IOP were steroid response in 21 eyes (64%; 10 eyes with V4b, 11 eyes with V4c, retained viscoelastic in 5 eyes (15% (3 with V4b, 2 with V4c, pupillary block in four eyes (12%; 3 with V4b, 1 with V4c, malignant glaucoma in one eye (3%, V4b, and missed pre-existing Juvenile open angle glaucoma (JOAG in two eyes (6% with V4b. Elevated IOP in 31 eyes resolved with conservative management. One eye (centraFLOW design with central aquaport block by viscoelastic, needed AC wash and one eye with malignant glaucoma needed parsplana vitrectomy and hyaloidotomy. Ten eyes required longterm (>2 months antiglaucoma medications (AGM for IOP control. Except the two eyes with JOAG, none had disc and field damage.In our series, OHT was seen in 4.85% and glaucoma in 0.3% eyes that underwent V4b and V4c model ICL implantation. Multiple etiologies were noted and steroid induced ocular hypertension was the most common cause of elevated IOP followed by retained viscoelastic and pupillary block. One third of these eyes required longterm AGM for IOP control.

  8. Effects of SCN lesions on circadian blood pressure rhythm in normotensive and transgenic hypertensive rats

    NARCIS (Netherlands)

    Witte, K.; Schnecko, A.; Buijs, R. M.; van der Vliet, J.; Scalbert, E.; Delagrange, P.; Guardiola-Lemaître, B.; Lemmer, B.

    1998-01-01

    Transgenic hypertensive TGR(mREN2)27 (TGR) rats, carrying an additional mouse renin gene, have been found to show inverse circadian blood pressure profiles compared to normotensive Sprague-Dawley rats. In order to evaluate the contributions of the suprachiasmatic nucleus (SCN) and the neurohormone

  9. Efficacy of brimonidine in preventing intraocular pressure spikes following phacoemulsification in glaucoma patients.

    Science.gov (United States)

    Kandarakis, Artemios; Soumplis, Vasileios; Karampelas, Michalis; Panos, Christos; Kyriakos, Nikolaos; Baxevanakis, Anastasios; Karagiannis, Dimitrios

    2010-01-01

    To measure intraocular pressure (IOP) elevation 6 and 24 hours after phacoemulsification in patients with glaucoma and to investigate the efficacy of brimonidine tartrate 0.2% in preventing IOP rise on the first postoperative day following cataract surgery. In this prospective randomized single-masked study, 86 eyes of 78 patients with well-controlled open-angle glaucoma were scheduled for phacoemulsification surgery. Patients were randomly assigned into 2 groups. Group A received 1 drop of brimonidine tartrate 0.2% and group B, which served as a control group, received 1 drop of artificial tears. Intraocular pressure was measured at baseline, before surgery, and 6 and 24 hours postoperatively. Within each group, we found a statistically significant difference in IOP between baseline and 6 hours postoperatively (pbrimonidine group was 18.52±4.58 mmHg, compared with 20.86±3.79 mmHg in the control group. Treatment with brimonidine tartrate 0.2% significantly reduced postoperative IOP elevation 6 hours following cataract extraction (p=0.009). Patients with medically well-controlled glaucoma may experience a substantial increase in IOP shortly after phacoemulsification surgery. Instillation of brimonidine tartrate 0.2%, although it significantly reduced IOP elevation following cataract operation, did not completely prevent IOP spikes.

  10. The effect of long-term use of intranasal steroids on intraocular pressure

    Directory of Open Access Journals (Sweden)

    Şimşek A

    2016-06-01

    Full Text Available Ali Şimşek,1 Cem Bayraktar,2 Sedat Doğan,2 Mehmet Karataş,2 Yasin Sarıkaya2 1Department of Ophthalmology, 2Department of Otolaryngology Head and Neck Surgery, Adıyaman University Research and Education Hospital, Adıyaman, Turkey Abstract: Long-term use of topical nasal steroids (especially older generation steroids has been shown to elevate intraocular pressure (IOP, but newer intranasal steroids are thought to have a minimal effect on IOP because of their low bioavailability. This study aimed to investigate alterations in IOP with two commonly used intranasal steroids for a 6-month period of time. One-hundred allergic rhinitis patients, divided equally into two groups, used mometasone furoate and fluticasone furoate intranasal steroids for 6 months. IOPs were measured before treatment and repeated at the 3rd, 6th, 12th, and 24th weeks of treatment. The IOPs of the groups were then compared. No statistically significant alteration was observed between the groups during the treatment time period. It was found that new generation intranasal steroids can be used safely, and there may not be an increased risk of IOP elevation in prolonged use in normal healthy people. Keywords: intraocular pressure, nasal steroids, prolonged use, allergic rhinitis

  11. Intraocular pressure fluctuation before and after strabismus surgery: a systematic review

    Directory of Open Access Journals (Sweden)

    Aliakbar Saber Moghaddam

    2015-12-01

    Full Text Available Introduction: Intraocular pressure (IOP can be influenced by several factors including corneal thickness, gender, refractive error, and the presence of diabetes mellitus. In the present study, we systematically reviewed published literature to find association between variations of IOP due to strabismus surgery.Method: PubMed and Scopus were systematically searched with the following search terms: (intraocular pressure OR IOP AND (strabismus for the articles in which the fluctuation of IOP before and after strabismus surgery had been evaluated. All types of articles including case series, cross-sectional, clinical trials, and cohort studies with no time limitation were included in this study. Systematically searches, selection of articles, and the extraction of data were performed by two reviewers independently.Result: 1617 out of 1674 articles were excluded due to duplication or irrelevancy. After step by step process of article selection, 57 relevant articles were included for further evaluation. However, only 8 articles met the inclusion criteria.Conclusions: The results of this report showed that IOP may vary due to strabismus surgery, and it decreases after the surgery.

  12. Nonarteritic Ischemic Optic Neuropathy Due to the Increased Intraocular Pressure During Cataract Surgery: A Case Report

    Directory of Open Access Journals (Sweden)

    Sadık Etka Bayramoğlu

    2017-09-01

    Full Text Available A 46-year-old patient diagnosed with rheumatoid arthritis underwent cataract surgery for a subcapsular cataract. Perioperative intraocular pressure (IOP increased after two sideport incisions. Despite administration of 300 cc of 20% mannitol, the elevated IOP persisted for 30 minutes. IOP decreased after pressing the posterior surface of the sideports with a 25 G cannula. The other steps of cataract surgery and intraocular lens implantation were performed uneventfully. On the first postoperative day, the diagnosis of nonarteritic ischemic optic neuropathy (NAION, which was thought to be the result of increased IOP in the perioperative period, was recorded. Cataract surgeons keep in mind and urgently perform simple maneuvers to lower IOP in order to prevent unexpected vision-threatening complications, such as NAION. In addition, for patients who have a crowded optic nerve head with a small cup-to-disc ratio or a previous episode of NAION in the other eye, perioperative and postoperative ocular pressure must be attentively managed.

  13. Influence of mitomycin C to intraocular pressure and blood flow of glaucoma patients after trabeculectomy

    Directory of Open Access Journals (Sweden)

    Quan Gu

    2015-07-01

    Full Text Available AIM:To explore the efficacy and safety of mitomycin C used in trabeculectomy by analyzing intraocular pressure and blood flow. METHODS: A total of 103 patients with glaucoma were divided into 2 groups randomly, and all patients were treated with trabeculectomy, while patients in the observation group were given mitomycin C extra. At 6~12mo follow-up were completed after operation, and the clinical efficacy, complications and hemodynamic characteristics of central retinal artery were compared between groups. RESULTS: The clinical efficacy of the observation group was higher than that of the controls(PP>0.05, but the complication type was differentiate to some extent. Low intraocular pressure and photophobia symptoms occurred mostly in the observation group, while cicatricial obstruction occurred mostly in the controls. Before treatment, there was no significant difference in hemodynamic characteristics between groups(P>0.05. One month after treatment, the peak systolic velocity(PSVand end diastolic velocity(EDVof the observation group were obviously lower, while resistance index(RIand pulsatility index(PIwere higher than those of the controls, the difference was statistically significant(PPCONCLUSION: Mitomycin C has a short-term harmful effect on glaucoma patients after trabeculectomy, but its long-term effect is safe and reliable.

  14. Intraocular pressure and Schirmer tear test values in maned wolf (Chrysocyon brachyurus

    Directory of Open Access Journals (Sweden)

    Cristiane S. Honsho

    Full Text Available Abstract: The purpose of this study was to establish baseline data on lacrimal quantity (STT-1 and intraocular pressure (IOP in captive maned wolves. Ten healthy adult maned wolves were contained with a snare pole and muzzle and kept in decubitus of the left side. STT-1 measurement was performed on the lateral third of the lower conjunctival sac for one minute. The cornea was desensitized and intraocular pressure was measured with an tonopen. Average STT-1 in both eyes was 11±5mm.min-1, with no statistical difference between the left and right eye (p=0.960. Average IOP in both eyes was 20±6mmHg, with no statistical difference between the left and right eye (p=0.836. Average STT-1 was lower than, and IOP was the same as normal levels found in dogs. There was no statistical difference in the age of the animals, and STT-1 and IOP values. In the present paper, average maned wolf STT-1 levels were lower compared with those found in dogs, while the IOP was the same in maned wolves as in dogs. Due to the increased incidence in providing emergency care for maned wolf victims of road kill and fires, determination reference values of ocular parameters may improve the correct diagnosis and treatment of the disease.

  15. Effects of unoprostone on diurnal variation of intraocular pressure in healthy volunteers

    Directory of Open Access Journals (Sweden)

    Inoue K

    2011-07-01

    Full Text Available Kenji Inoue1, Kei Noguchi1, Masato Wakakura1, Goji Tomita21Inouye Eye Hospital, Tokyo; 22nd Department of Ophthalmology, Toho University School of Medicine, Tokyo, JapanPurpose: To prospectively evaluate the diurnal variation of intraocular pressure (IOP during unoprostone treatment in 13 healthy volunteers.Method: IOP was measured by Goldmann applanation tonometry by the same observer every 3 hours from 9 am to 9 am the next morning. Unoprostone was then instilled at 9 am and 9 pm daily for 1 month. After 1 month, IOP was measured again with unoprostone instilled at 9 am and 9 pm during IOP measurement. We then compared the average daily IOP before and after the treatment (paired t-test.Results: After 1 month of treatment, the average IOP decreased at every time point but one (12 pm, 3 pm, 6 pm, 9 pm, 12 am, 3 am, and 9 am, but not at 6 am. There were no adverse reactions and none of the subjects discontinued unoprostone.Conclusion: The hypotensive effects of unoprostone persist throughout the day, but this study suggests that the effects may be weaker at nighttime and early in the morning.Keywords: unoprostone, intraocular pressure, diurnal variation, healthy volunteer

  16. Intraocular pressure and corneal biomechanical properties in patients with myotonic dystrophy.

    Science.gov (United States)

    Rosa, Nicola; Lanza, Michele; Borrelli, Maria; Palladino, Alberto; Di Gregorio, M Grazia; Politano, Luisa

    2009-02-01

    To compare intraocular pressure (IOP) between patients with myotonic dystrophy (DM1) and normal subjects, taking into account corneal characteristics. To determine whether lower IOP measurements in patients with DM1 are due to thinner corneas. Comparative case series. Fifty-three eyes of patients with DM1 and 53 eyes of normal age- and sex-matched subjects. Corneal biomechanical properties and corneal compensated intraocular pressure (IOPcc) measured with the Ocular Response Analyzer (Reichert Inc., Depew, NY), central corneal thickness measured with the Oculus Pentacam (Oculus, Wetzlar, Germany), and IOP were evaluated in patients with DM1 and compared with age- and sex-matched healthy subjects. Goldmann applanation tonometry, central corneal thickness, corneal hysteresis (CH), corneal resistance factor (CRF), and IOPcc. Compared with the healthy subjects, patients with DM1 showed lower IOP (12.4+/-3.6 mm Hg vs. 14.9+/-3.4 mmHg) (Pcornea (575.9+/-35.02 mum vs. 556.3+/-33.2 microm) (Pbiomechanical properties. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

  17. Effect of oral administration of carprofen on intraocular pressure in normal dogs.

    Science.gov (United States)

    Meekins, J M; Overton, T L; Rankin, A J; Roush, J K

    2016-08-01

    The aim of this study was to determine the effect of oral administration of carprofen on intraocular pressure in normal dogs. Twelve young adult beagle dogs were randomly assigned to treatment (n = 6) or control (n = 6) groups. After an 11-day acclimation period, the treatment group received approximately 2.2 mg/kg carprofen per os every 12 h for 7 days, and the control group received a placebo gel capsule containing no drug per os every 12 h for 7 days. Intraocular pressure (IOP) was measured by a rebound tonometer at three time points per day (8 am, 2 pm, and 8 pm) during the acclimation (days 1-11) and treatment (days 12-18) phases and for 48 h (days 19-20) after the completion of treatment. There was no statistically significant change in IOP for either eye in the dogs receiving oral carprofen during the treatment phase (days 12-18). After day 4, no significant daily IOP changes were seen in control group dogs. Carprofen administered orally every 12 h for 7 days had no effect on IOP in normal beagle dogs. An acclimation period to frequent IOP measurements of at least 5 days is necessary to establish baseline IOP values and minimize possible anxiety-related effects on IOP measurements. © 2016 John Wiley & Sons Ltd.

  18. Corneal hysteresis and intraocular pressure measurement in children using the reichert ocular response analyzer.

    Science.gov (United States)

    Kirwan, Caitriona; O'Keefe, Michael; Lanigan, Bernadette

    2006-12-01

    To examine corneal hysteresis in children with normal eyes and congenital glaucoma and assess intraocular pressure (IOP) measurement with the Reichert Ocular Response Analyzer (RORA). Observational, cross-sectional study. setting: Clinical practice. patients: Corneal hysteresis and intraocular pressure (Goldmann correlated [IOPg] and corneal compensated [IOPcc]) were recorded with RORA. IOP was also measured by Goldmann applanation tonometry. Mean corneal hysteresis of 12.5 mm Hg was recorded in 81 [corrected] normal eyes of 42 children. It was markedly lower (mean 6.3 mm Hg) in 11 eyes of eight children with congenital glaucoma. No correlation was found between age and corneal hysteresis (r = -0.08). IOPg did not differ significantly from Goldmann applanation tonometry (P = .27). IOPcc was statistically significantly greater than IOPg (P = .014). RORA measurement was not possible in the presence of nystagmus but was possible with applanation tonometry. Cooperation with IOP measurement was much higher with RORA (89.8%) compared with applanation tonometry (78.7%). Corneal hysteresis in children is similar to that reported in adults. No correlation was found with age. In the presence of nystagmus, IOP measurement was possible with Goldmann applanation tonometry but not RORA. Cooperation with IOP measurement was better with RORA than with Goldmann applanation tonometry.

  19. Attempted eyelid closure affects intraocular pressure measurement in open-angle glaucoma patients.

    Science.gov (United States)

    Jamal, Karim N; Gürses-Ozden, RabIa; Liebmann, Jeffrey M; Ritch, Robert

    2002-08-01

    To evaluate the effect of attempted eyelid closure on intraocular pressure (IOP) measurements in normal-tension (NTG) and high-tension (HTG) open-angle glaucoma patients. Prospective clinical trial. Forty randomly selected eyes of 40 patients underwent corneal pachymetry and IOP measurements using both Goldmann applanation tonometry and Tono-pen XL (Mentor, Inc., Norwell, Massachusetts, USA). Intraocular pressure was measured by the same examiner holding the eyelids open, both with and without the subject simultaneously attempting forced eyelid closure. Subjects were seated during all measurements and waited 5 minutes between measurements with each instrument; the order of measurement was randomized. Twenty NTG and 20 HTG eyes were enrolled. The mean age was 63.0 +/- 13.0 years (range, 31-80 years). The average corneal thickness was 540 +/- 32 microm (range, 480-608 microm) in NTG patients and 552 +/- 40 microm (range, 449-610 microm) in HTG patients (P =.07, analysis of variance [ANOVA]). Using Goldmann applanation tonometry, IOP measurement in eyes with NTG increased by 3.9 +/- 2.0 mm Hg with attempted eyelid closure (P pen XL, IOP measurements increased 4.2 +/- 2.7 mm Hg (P pen XL, measurements increased 4.5 +/- 2.0 mm Hg (P tonometry is a significant and common source of error in eyes with glaucoma and may influence the clinical management and decision-making in the treatment of NTG and HTG.

  20. Tafluprost once daily for treatment of elevated intraocular pressure in patients with open-angle glaucoma

    Directory of Open Access Journals (Sweden)

    Liu Y

    2012-12-01

    Full Text Available Yang Liu, Weiming MaoDepartment of Cell Biology and Anatomy, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TXAbstract: Glaucoma is a leading cause of visual loss worldwide. Current antiglaucoma therapy focuses on lowering intraocular pressure to a safe level. In recent years, prostaglandin analogs have become the first-line agents for treating open angle glaucoma. Tafluprost, which was first reported in 2003, is a novel prostaglandin analog, and has been shown to be a potent ocular hypotensive agent in a number of preclinical and clinical studies. Also, its unique preservative-free formulation helps to decrease preservative-associated ocular disorders and improve patient compliance. In this review, studies from 2003 to 2012 focusing on the structure, metabolism, efficacy, and safety of tafluprost are summarized. These studies suggested that application of tafluprost once daily is a safe and effective treatment for patients with open angle glaucoma.Keywords: tafluprost, prostaglandin analog, glaucoma, intraocular pressure, preservative-free formulation

  1. The heritability of glaucoma-related traits corneal hysteresis, central corneal thickness, intraocular pressure, and choroidal blood flow pulsatility.

    Science.gov (United States)

    Freeman, Ellen E; Roy-Gagnon, Marie-Hélène; Descovich, Denise; Massé, Hugues; Lesk, Mark R

    2013-01-01

    The purpose of this work was to investigate the heritability of potential glaucoma endophenotypes. We estimated for the first time the heritability of the pulsatility of choroidal blood flow. We also sought to confirm the heritability of corneal hysteresis, central corneal thickness, and 3 ways of measuring intraocular pressure. Measurements were performed on 96 first-degree relatives recruited from Maisonneuve-Rosemont Hospital in Montreal. Corneal hysteresis was determined using the Reichert Ocular Response Analyser. Central corneal thickness was measured with an ultrasound pachymeter. Three measures of intraocular pressure were obtained: Goldmann-correlated and corneal compensated intraocular pressure using the Ocular Response Analyser, and Pascal intraocular pressure using the Pascal Dynamic Contour Tonometer. The pulsatility of choroidal blood velocity and flow were measured in the sub-foveolar choroid using single-point laser Doppler flowmetry (Oculix). We estimated heritability using maximum-likelihood variance components methods implemented in the SOLAR software. No significant heritability was detected for the pulsatility of choroidal blood flow or velocity. The Goldman-correlated, corneal compensated, and Pascal measures of intraocular pressure measures were all significantly heritable at 0.94, 0.79, and 0.53 after age and sex adjustment (p = 0.0003, p = 0.0023, p = 0.0239). Central corneal thickness was significantly heritable at 0.68 (p = 0.0078). Corneal hysteresis was highly heritable but the estimate was at the upper boundary of 1.00 preventing us from giving a precise estimate. Corneal hysteresis, central corneal thickness, and intraocular pressure are all heritable and may be suitable as glaucoma endophenotypes. The pulsatility of choroidal blood flow and blood velocity were not significantly heritable in this sample.

  2. The heritability of glaucoma-related traits corneal hysteresis, central corneal thickness, intraocular pressure, and choroidal blood flow pulsatility.

    Directory of Open Access Journals (Sweden)

    Ellen E Freeman

    Full Text Available PURPOSE: The purpose of this work was to investigate the heritability of potential glaucoma endophenotypes. We estimated for the first time the heritability of the pulsatility of choroidal blood flow. We also sought to confirm the heritability of corneal hysteresis, central corneal thickness, and 3 ways of measuring intraocular pressure. METHODS: Measurements were performed on 96 first-degree relatives recruited from Maisonneuve-Rosemont Hospital in Montreal. Corneal hysteresis was determined using the Reichert Ocular Response Analyser. Central corneal thickness was measured with an ultrasound pachymeter. Three measures of intraocular pressure were obtained: Goldmann-correlated and corneal compensated intraocular pressure using the Ocular Response Analyser, and Pascal intraocular pressure using the Pascal Dynamic Contour Tonometer. The pulsatility of choroidal blood velocity and flow were measured in the sub-foveolar choroid using single-point laser Doppler flowmetry (Oculix. We estimated heritability using maximum-likelihood variance components methods implemented in the SOLAR software. RESULTS: No significant heritability was detected for the pulsatility of choroidal blood flow or velocity. The Goldman-correlated, corneal compensated, and Pascal measures of intraocular pressure measures were all significantly heritable at 0.94, 0.79, and 0.53 after age and sex adjustment (p = 0.0003, p = 0.0023, p = 0.0239. Central corneal thickness was significantly heritable at 0.68 (p = 0.0078. Corneal hysteresis was highly heritable but the estimate was at the upper boundary of 1.00 preventing us from giving a precise estimate. CONCLUSION: Corneal hysteresis, central corneal thickness, and intraocular pressure are all heritable and may be suitable as glaucoma endophenotypes. The pulsatility of choroidal blood flow and blood velocity were not significantly heritable in this sample.

  3. Circadian regulation of sleep and the sleep EEG under constant sleep pressure in the rat.

    Science.gov (United States)

    Yasenkov, Roman; Deboer, Tom

    2010-05-01

    Sleep is regulated by homeostatic and circadian processes. Slow wave activity (SWA; 1-4 Hz) in the NREM sleep electroencephalogram (EEG) reflects sleep homeostasis. Activity of faster EEG frequencies (10-25 Hz) is thought to be under influence of circadian factors. The relative contribution of both processes to the distribution of sleep and wakefulness and EEG activity in rodents remains uncertain. Continuous EEG recording in rats in constant dark conditions (DD) were performed and a sleep deprivation protocol consisting of 2 h sleep deprivation followed by 2 h of rest (2h/2h) was applied for 48 h to obtain a constant sleep pressure. Basic sleep research laboratory. Adult male Wistar rats. Sleep deprivation. Under the 2h/2h protocol, the circadian modulation of waking, NREM and REM sleep was markedly reduced compared to the baseline, affecting the frequency of vigilance state episodes and the duration of REM sleep and waking episodes. In contrast, NREM sleep episode duration still showed a daily modulation. Consecutive 2h values of SWA in NREM sleep were stabile during the 2h\\2h protocol, while NREM sleep EEG activity within the higher frequencies (7-25 Hz) still demonstrated strong circadian modulation, which did not differ from baseline. In rats, the daily modulation of REM sleep is less pronounced compared to NREM sleep and waking. In contrast to SWA, activity in higher frequencies (7-25 Hz) in the NREM sleep EEG have an endogenous circadian origin and are not influenced by sleep homeostatic mechanisms.

  4. Laser-assisted formation of micropores and nanobubbles in sclera promote stable normalization of intraocular pressure

    Science.gov (United States)

    Baum, Olga; Wachsmann-Hogiu, Sebastian; Milner, Thomas; Sobol, Emil

    2017-06-01

    Pores in sclera enhance uveoscleral water outflow and can normalize intraocular pressure in glaucomatous eyes. The aims of this study are to demonstrate laser-induced formation of pores with a dendritic structure and to answer the questions: How is a pore system stable and can laser treatment provide a long-lasting pressure stabilization effect? Effect of 1.56 µm laser radiation on porcine eye sclera was studied using atomic force microscopy and super resolution structured irradiation microscopy with fluorescent markers. Results suggest that the pores with a complex spatial configuration can arise as a result of laser irradiation and that laser-generated stable gas nanobubbles coated with calcium ions allow pore stabilization in the sclera. Our results support a laser based approach for treatment of glaucoma.

  5. The effects of intraocular pressure elevation on optic nerve axonal transport in the monkey

    Energy Technology Data Exchange (ETDEWEB)

    Shirakashi, Motohiro (Department of Ophtalmology, Niigata University, School of Medicine, Niigata (Japan))

    1990-01-01

    Blockage of axonal transport by intraocular pressure (IOP) elevation was studied quantitatively in monkey eyes, using liquid scintillation counting. After 5 h of IOP elevation (perfusion pressure of 30 mmHg), axonally transported protein was measured in the distal third of each optic nerve, which was divided into superotemporal, inferotemporal, superonasal, and inferonasal portions. The ratio of the amount of radioactive protein in each portion of the optic nerve to that in the whole optic nerve was calculated. In eyes with IOP elevation, the mean ratio for the temporal optic nerve was significantly lower than that for the nasal optic nerve. It appeared that axonal transport was not affected homogenously throughout the optic nerve but was more impaired in the temporal half of the optic nerve following IOP elevation. (author).

  6. Reversal of retinal ganglion cell dysfunction after surgical reduction of intraocular pressure.

    Science.gov (United States)

    Sehi, Mitra; Grewal, Dilraj S; Goodkin, Margot L; Greenfield, David S

    2010-12-01

    The pattern electroretinogram optimized for glaucoma screening (PERGLA) is a noninvasive method of objectively measuring retinal ganglion cell (RGC) function. This study was undertaken to quantify the RGC response to intraocular pressure (IOP) reduction after glaucoma surgery. Prospective cohort study. Forty-seven eyes of 47 patients with uncontrolled IOP or progressive glaucomatous optic neuropathy receiving maximal medical therapy requiring trabeculectomy or aqueous drainage device implantation who met eligibility criteria. Eyes with visual acuity less than 20/30, corneal or retinal pathologic features, or unreliable standard automated perimetry (SAP) results were excluded. All patients underwent complete ocular examination, arterial blood pressure, SAP, and PERGLA at 2 sessions before surgery and at 3 months after surgery. Mean ocular perfusion pressure (MOPP) was calculated. Each measure of PERGLA amplitude and phase was an average of 600 artifact-free signal registrations. Intraocular pressure and PERGLA amplitude and phase. Forty-seven eyes of 47 patients (mean age ± standard deviation [SD], 69.9 ± 11.3 years) were enrolled. Thirty-four eyes (72%) underwent trabeculectomy with antifibrosis therapy; 13 eyes (28%) underwent glaucoma drainage implant surgery. Mean ± SD postoperative IOP (10.4 ± 4.6 mmHg) was significantly (Pradian) was significantly (P = 0.01) reduced compared with preoperative PERGLA phase (1.81 ± 0.22 π-radian). Mean ± SD postoperative MOPP (53.1 ± 6.4 mmHg) was significantly (P 0.05) was identified between change in PERGLA amplitude and change in IOP or MOPP. Reversal of RGC dysfunction occurs after surgical reduction of IOP and may be quantified using PERGLA. Copyright © 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  7. [Circadian blood pressure characteristics in hospitalized unstable angina pectoris patients with hypertension].

    Science.gov (United States)

    Zhang, W; Zhu, H; Yao, S Y; Li, Y; Liu, J; Xue, H

    2017-07-24

    Objective: To define the characteristic of circadian rhythm of blood pressure in unstable angina pectoris (UAP)patients with hypertension and its effects on the cardiovascular events. Methods: It was a prospective study.Based on coronary angiographic results, 742 consecutive hospitalized UAP patients with hypertension and 89 consecutive hospitalized hypertensive patients were recruited between September 2014 and December 2015 in this study. Clinical data and the results of 24-hour ambulatory blood pressure monitoring (ABPM) were analyzed. Results: The total prevalence of hypertension in UAP is about 77.1%(742/962) in our cohort. The decrease of night-time systolic and diastolic blood pressure in UAP patients complicated with hypertension was lower than that in hypertensive patients (Preverse dipper pattern was 12.4%(92/742), 34.9%(259/742) and 52.7%(391/742) in UAP patients complicated with hypertension, 18.0%(16/89), 48.3%(43/89) and 33.7%(30/89) in hypertensive patients. Obviously, the abnormal circadian rhythm of blood pressure was more significant in UAP patients with hypertension than in hypertensive patients, characterized by higher reverse dipper pattern in UAP patients with hypertension compared to patients with hypertension(P=0.00), similar results were evidenced among the male and female patients and patients with various ages. Subgroup analysis showed that except similar results on the incidence of reverse dipper pattern in controlled blood pressure aged less than 45 years old, the incidence of reverse dipper pattern was all significantly higher in UAP patients complicating with hypertension than in hypertensive patients independent no matter blood pressure controlled or not (all Plogistic regression analysis showed that reverse dipper pattern was independently associated with UAP(OR=1.53, 95%CI 1.12-2.61). Conclusions: This finding suggests that UAP patients with hypertension often have abnormal circadian rhythm, characterized by higher reverse dipper

  8. Circadian variation of blood pressure in patients with chronic renal failure on continuous ambulatory peritoneal dialysis

    DEFF Research Database (Denmark)

    Clausen, P; Feldt-Rasmussen, B; Ladefoged, Jens

    1995-01-01

    The circadian pattern of blood pressure variation was investigated in 10 patients with advanced chronic renal failure on continuous ambulatory peritoneal dialysis (CAPD) and in an age-matched group of controls without renal disease with similar office blood pressure level. Monitoring was done using....... In patients with chronic renal failure undergoing CAPD, an otherwise unnoticed 24-h hypertension and nocturnal blood pressure elevation can be discovered by use of 24-h blood pressure monitoring and this may indicate a need of earlier start of antihypertensive treatment in CAPD patients with borderline...

  9. Influence of Corneal Opacity on Intraocular Pressure Assessment in Patients with Lysosomal Storage Diseases.

    Science.gov (United States)

    Wasielica-Poslednik, Joanna; Politino, Giuseppe; Schmidtmann, Irene; Lorenz, Katrin; Bell, Katharina; Pfeiffer, Norbert; Pitz, Susanne

    2017-01-01

    To investigate an influence of mucopolysaccharidosis (MPS)- and Morbus Fabry-associated corneal opacities on intraocular pressure (IOP) measurements and to evaluate the concordance of the different tonometry methods. 25 MPS patients with or without corneal clouding, 25 Fabry patients with cornea verticillata ≥ grade 2 and 25 healthy age matched controls were prospectively included into this study. Outcome measures: Goldmann applanation tonometry (GAT); palpatory assessment of IOP; Goldmann-correlated intraocular pressure (IOPg), corneal-compensated intraocular pressure (IOPcc), corneal resistance factor (CRF) and corneal hysteresis (CH) assessed by Ocular Response Analyzer (ORA); central corneal thickness (CCT) and density assessed with Pentacam. Statistical analysis was performed using linear mixed effect models and Spearman correlation coefficients. The concordance between tonometry methods was assessed using Bland-Altman analysis. There was no relevant difference between study groups regarding median GAT, IOPg, IOPcc and CCT measurements. The limits of agreement between GAT and IOPcc/IOPg/palpatory IOP in MPS were: [-11.7 to 12.1mmHg], [-8.6 to 15.5 mmHg] and [- 5.4 to 10.1 mmHg] respectively. Limits of agreement were less wide in healthy subjects and Fabry patients. Palpatory IOP was higher in MPS than in healthy controls and Fabry patients. Corneal opacity correlated more strongly with GAT, IOPg, CH, CRF, CCT and corneal density in MPS (r = 0.4, 0.5, 0.5, 0.7, 0.6, 0.6 respectively) than in Fabry patients (r = 0.3, 0.2, -0.03, 0.1, 0.3, -0.2 respectively). In contrast, IOPcc revealed less correlation with corneal opacity than GAT in MPS (r = 0.2 vs. 0.4). ORA and GAT render less comparable IOP-values in patients suffering from MPS-associated corneal opacity in comparison to Fabry and healthy controls. The IOP seems to be overestimated in opaque MPS-affected corneas. GAT, IOPg and biomechanical parameters of the cornea correlate more strongly with the corneal

  10. Circadian variations in blood pressure in health and disease: implications for patient management

    Directory of Open Access Journals (Sweden)

    Slaughter MS

    2011-08-01

    Full Text Available Atul R Chugh1, John H Loughran1, Mark S Slaughter21Division of Cardiovascular Medicine, 2Division of Thoracic and Cardiovascular Surgery, University of Louisville, Louisville, KY, USAAbstract: Traditionally, blood pressure measurements have been performed in office settings and have provided the basis for all diagnostic and therapeutic decisions. However, the development of a clinically relevant 24-hour blood pressure monitoring system has added greatly to the ability of blood pressure values to confer additional clinical information, including prognostic value. Mechanistically, the circadian rhythm of blood pressure is mediated by a complex process as a part of the neurohormonal cascade. Pattern recognition of blood pressure peaks and troughs over a 24-hour period has led to categorization into specific subsets namely, ie, dippers, nondippers, extreme dippers, and reverse dippers. Cardiovascular risk is associated with certain pattern types, as has been demonstrated in large observational and prospective studies. The development of therapies for the purpose of restoring more pathological patterns to normal ones continues to grow. These include both pharmaceutical and device therapy. This article describes the development of 24-hour blood pressure monitoring systems, the identification of circadian blood pressure patterns, and the treatment strategies studied thus far which affect these newer blood pressure parameters.Keywords: ambulatory blood pressure measurement, nocturnal blood pressure, dippers, nondippers, extreme dippers, device therapy

  11. INTRAOCULAR PRESSURE, MEAN ARTERIAL BLOOD PRESSURE AND PUPILLARY DIAMETER IN RABBITS ( (Oryctolagus cuniculus SUBJECTED TO RETROBULBAR BLOCK WITH DIFFERENT ANESTHETIC PROTOCOLS

    Directory of Open Access Journals (Sweden)

    Renata Maria Monção da Silva

    2015-10-01

    Full Text Available The aim of this study was to evaluate four protocols of loco regional anesthesia for ophthalmic procedures that could provide safety and life support, in addition to maintain intraocular pressure stable, with eye centralization and eyelid akinesia. 20 New Zealand rabbits were used to perform local anesthesia by retrobulbar block with four protocols: 2% lidocaine with epinephrine, 2% lidocaine without epinephrine associated with tramadol, 1% ropivacaine and bupivacaine 0.5 %. Each animal received an anesthetic volume of 1 mL. All anesthetic protocols used promoted eyelid akinesia and centralization of the eye during the assessment period. The retrobulbar block with the proposed anesthetic protocols proved to be feasible and safe for the maintenance of intraocular pressure, invasive blood pressure and pupillary diameter and can be used in intraocular surgeries, respecting the time of action of each anesthetic. All protocols showed an excellent blockage action but bupivacaine promoted the highest pupil diameter compared to the other drugs tested.

  12. Effect of altered eating habits and periods during Ramadan fasting on intraocular pressure, tear secretion, corneal and anterior chamber parameters

    NARCIS (Netherlands)

    Kerimoglu, H.; Ozturk, B.; Gunduz, K.; Bozkurt, B.; Kamis, U.; Okka, M.

    Purpose To determine whether altered eating habits and periods, especially the pre-dawn meal, during Ramadan fasting have any significant effect on intraocular pressure (IOP), tear secretion, corneal and anterior chamber parameters. Methods IOP, basal tear secretion (BTS), reflex tear secretion

  13. Genome-wide analysis of multi-ancestry cohorts identifies new loci influencing intraocular pressure and susceptibility to glaucoma

    NARCIS (Netherlands)

    Hysi, Pirro G.; Cheng, Ching-Yu; Springelkamp, Henriet; Macgregor, Stuart; Bailey, Jessica N. Cooke; Wojciechowski, Robert; Vitart, Veronique; Nag, Abhishek; Hewitt, Alex W.; Hohn, Rene; Venturini, Cristina; Mirshahi, Alireza; Ramdas, Wishal D.; Thorleifsson, Gudmar; Vithana, Eranga; Khor, Chiea-Chuen; Stefansson, Arni B.; Liao, Jiemin; Haines, Jonathan L.; Amin, Najaf; Wang, Ya Xing; Wild, Philipp S.; Ozel, Ayse B.; Li, Jun Z.; Fleck, Brian W.; Zeller, Tanja; Staffieri, Sandra E.; Teo, Yik-Ying; Cuellar-Partida, Gabriel; Luo, Xiaoyan; Allingham, R. Rand; Richards, Julia E.; Senft, Andrea; Karssen, Lennart C.; Zheng, Yingfeng; Bellenguez, Celine; Xu, Liang; Iglesias, Adriana I.; Wilson, James F.; Kang, Jae H.; van Leeuwen, Elisabeth M.; Jonsson, Vesteinn; Thorsteinsdottir, Unnur; Despriet, Dominiek D. G.; Ennis, Sarah; Moroi, Sayoko E.; Martin, Nicholas G.; Jansonius, Nomdo M.; Yazar, Seyhan; Tai, E-Shyong; Amouyel, Philippe; Kirwan, James; van Koolwijk, Leonieke M. E.; Hauser, Michael A.; Jonasson, Fridbert; Leo, Paul; Loomis, Stephanie J.; Fogarty, Rhys; Rivadeneira, Fernando; Kearns, Lisa; Lackner, Karl J.; de Jong, Paulus T. V. M.; Simpson, Claire L.; Pennell, Craig E.; Oostra, Ben A.; Uitterlinden, Andre G.; Saw, Seang-Mei; Lotery, Andrew J.; Bailey-Wilson, Joan E.; Hofman, Albert; Vingerling, Johannes R.; Maubaret, Cecilia; Pfeiffer, Norbert; Wolfs, Roger C. W.; Lemij, Hans G.; Young, Terri L.; Pasquale, Louis R.; Delcourt, Cecile; Spector, Timothy D.; Klaver, Caroline C. W.; Small, Kerrin S.; Burdon, Kathryn P.; Stefansson, Kari; Wong, Tien-Yin; Viswanathan, Ananth; Mackey, David A.; Craig, Jamie E.; Wiggs, Janey L.; van Duijn, Cornelia M.; Hammond, Christopher J.; Aung, Tin

    2014-01-01

    Elevated intraocular pressure (IOP) is an important risk factor in developing glaucoma, and variability in IOP might herald glaucomatous development or progression. We report the results of a genome-wide association study meta-analysis of 18 population cohorts from the International Glaucoma

  14. Effect of pegaptanib sodium 0.3 mg intravitreal injections (Macugen) in intraocular pressure: posthoc analysis from VISION study

    NARCIS (Netherlands)

    Boyer, David S.; Goldbaum, Mauro; Leys, Anita M.; Starita, Carla; Blumenkranz, M.; Buyse, M.; Goldberg, M.; Gragoudas, E. S.; Miller, J.; Schwartz, S. D.; Singerman, L.; Yannuzzi, L.; Adamis, A. P.; Guyer, D. R.; O'Shaughnessy, D.; de Gronckel, S.; Fesneau, G.; Quinaux, E.; Tremolet, D.; Wang, K.; Brailey, A.; Finman, J.; Ting, N.; Bressler, N. M.; Bressler, S. B.; Denblow, R.; Schein, O. D.; Seabrook, S.; Solomon, S.; Schachat, A. P.; Philips, D.; Altaweel, M.; Davis, M. D.; Blodi, Ba; Danis, R. P.; Ip, M. S.; Hiner, C.; Elledge, J.; Webster, M.; Hannan, C.; Ficken, J.; Alexander, S.; Neider, M.; Wabers, H.; Vargo, P.; Lambert, E.; Kastorff, L.; Carr, A.; Shkiele, A.; Baliker, J.; Guymer, R.; Constable, I.; Arnold, J.; Sarks, S.; Chang, A.; Gillies, M.; Mitchell, P.; Haas, A.; Stur, M.; Leys, A.; Moreira, C.; Portella, E.; de Avila, M.; Taleb, Ac; Lavinsky, J.; Lavinsky, D.; Farah, M. E.; Williams, G.; Leonard, B.; Garcia, R.; Maberley, D.; Lopez, Jm; Rodriguez, F. J.; Fiser, I.; Larsen, M.; Korobelnik, J.-F.; Soubrane, G.; Koenig, F.; Gaudric, A.; Dithmar, S.; Holz, Fg; Joussen, A.; Kirchhof, B.; Wiedemann, P.; Pauleikhoff, D.; Schneider, U.; Suveges, I.; Gyory, J.; Pollack, A.; Loewenstein, A.; Rosenblatt, I.; Giovannini, A.; Menchini, U.; Brancato, R.; Cardillo Piccolino, F.; Grignolo, F. M.; Bandello, F.; Schlingemann, R. O.; Deutman, A.; Kaluzny, J.; Pecold, K.; Cunha-Vaz, J.; da Silva, R.; Ruiz Moreno, J. M.; Mones, J.; Figueroa, M.; Pournaras, C.; Zografos, L.; Lois, N.; Chakravarthy, U.; Hykin, P.; Chisholm, I.; Johnson, M. W.; Marcus, D. M.; Mandava, N.; Haller, Ja; Cangemi, F.; Boyer, D.; Kim, I.; Loewenstein, J.; Heier, J.; Reichel, E.; Falcone, P. M.; Weissgold, D. J.; Conway, B. P.; Garfinkel, R.; Glaser, B.; Lyon, A. T.; Lewis, H.; Wells, J. A.; Wilcox, L.; Fish, G.; Eliott, D.; Fekrat, S.; Taney, B.; Eaton, A. M.; Deramo, V.; Wroblewski, J.; Tom, D.; Chow, D. R.; Orth, D. H.; Packo, K. H.; Holz, E.; Mieler, W.; Kuppermann, B.; Sabates, N.; Cummings, H.; Pendergast, S. D.; Gonzales, C.; Lim, J. I.; Charles, S.; Sanislo, S.; Rosenfeld, P.; Connor, T.; Cantrill, H.; Willson, R.; Bailey-Freund, K.; Rosen, R.; Leonard, R.; Brucker, A.; Ho, A.; Sneed, S.; Friberg, T.; Klein, M.; Tornambe, P.; Stoller, G.; Capone, A.; Bernstein, P. S.; McDonald, H. R.; Schatz, H.; Johnson, R. N.; Nanda, M.; Avery, R.; Wong, K.; Grizzard, W. S.; Higgins, P.; Hudson, H.; Joffe, L.; Varenhorst, M.; Slusher, M. M.; Betts, F.; Cunningham, E.; Curtiss, K.; Harrison, E.; Katz, B.; Masonson, H. N.; DeMarco, R.; Beals, C.; Patel, M.; Rodriguez, I.; Starita, C.

    2014-01-01

    Objective To assess the rate of pegaptanib-associated sustained intraocular pressure (IOP) elevation. Methods A posthoc analysis was conducted on all IOP measurements, except the immediate 30-min postinjection, from all subjects randomised to pegaptanib 0.3 mg or sham injections continuously in the

  15. The influence of new beta-adrenolytics nebivolol and carvedilol on intraocular pressure and iris blood flow in rabbits.

    Science.gov (United States)

    Szumny, Dorota; Szeląg, Adam

    2014-06-01

    The aim of this study was to assess the influence of propranolol, nebivolol, and carvedilol on intraocular pressure and blood flow in vessels of rabbit's (New Zealand White) eyeball. The study was carried out on New Zealand white rabbits. Intraocular pressure was measured with the applanation tonometer Möller-Wedel and Icare; blood flow was measured with Doppler Laser Blood Flow Monitor MBD3. Following a single administration into a conjunctival sac, all drugs decreased intraocular pressure. Iris blood flow was decreased following administration of propranol, but increased by nebivolol and carvedilol. After single and repeated oral administration of nebivolol and carvedilol an IOP decrease was demonstrated, but with no effect of all applied doses on iris or retina/choroid blood flow. Studies performed on an animal model indicate that it is possible to reduce the intraocular pressure and increase ocular blood flow in humans, following topical administration of carvedilol and nebivolol. Confirmation of those results in clinical trials may lead to development of a new anti-glaucoma treatment. Further clinical studies of long-term nebivolol and carvedilol are recommended. They are necessary for evaluation of usefulness of those drugs for selected groups of patients, for example those with glaucoma and arterial hypertension.

  16. Genetic African Ancestry Is Associated With Central Corneal Thickness and Intraocular Pressure in Primary Open-Angle Glaucoma

    NARCIS (Netherlands)

    Bonnemaijer, P.W.M.; Cook, C.; Nag, A.; Hammond, C.J.; Duijn, C.M. van; Lemij, H.G.; Klaver, C.C.W.; Thiadens, A.

    2017-01-01

    Purpose: To unravel the relationship between African ancestry, central corneal thickness (CCT), and intraocular pressure (IOP) by estimating the genetic African ancestry (GAA) proportion in primary open-angle glaucoma (POAG) patients and controls from an admixed South African Colored (SAC) and a

  17. Mapping in-vivo optic nerve head strains caused by intraocular and intracranial pressures

    Science.gov (United States)

    Tran, H.; Grimm, J.; Wang, B.; Smith, M. A.; Gogola, A.; Nelson, S.; Tyler-Kabara, E.; Schuman, J.; Wollstein, G.; Sigal, I. A.

    2017-02-01

    Although it is well documented that abnormal levels of either intraocular (IOP) or intracranial pressure (ICP) can lead to potentially blinding conditions, such as glaucoma and papilledema, little is known about how the pressures actually affect the eye. Even less is known about potential interplay between their effects, namely how the level of one pressure might alter the effects of the other. Our goal was to measure in-vivo the pressure-induced stretch and compression of the lamina cribrosa due to acute changes of IOP and ICP. The lamina cribrosa is a structure within the optic nerve head, in the back of the eye. It is important because it is in the lamina cribrosa that the pressure-induced deformations are believed to initiate damage to neural tissues leading to blindness. An eye of a rhesus macaque monkey was imaged in-vivo with optical coherence tomography while IOP and ICP were controlled through cannulas in the anterior chamber and lateral ventricle, respectively. The image volumes were analyzed with a newly developed digital image correlation technique. The effects of both pressures were highly localized, nonlinear and non-monotonic, with strong interactions. Pressure variations from the baseline normal levels caused substantial stretch and compression of the neural tissues in the posterior pole, sometimes exceeding 20%. Chronic exposure to such high levels of biomechanical insult would likely lead to neural tissue damage and loss of vision. Our results demonstrate the power of digital image correlation technique based on non-invasive imaging technologies to help understand how pressures induce biomechanical insults and lead to vision problems.

  18. Additive Intraocular Pressure-Lowering Effects of Ripasudil with Glaucoma Therapeutic Agents in Rabbits and Monkeys

    Directory of Open Access Journals (Sweden)

    Yoshio Kaneko

    2017-01-01

    Full Text Available Ripasudil hydrochloride hydrate (K-115, a specific Rho-associated coiled-coil containing protein kinase (ROCK inhibitor, is developed for the treatment of glaucoma and ocular hypertension. Topical administration of ripasudil decreases intraocular pressure (IOP by increasing conventional outflow through the trabeculae to Schlemm’s canal, which is different from existing agents that suppress aqueous humor production or promote uveoscleral outflow. In this study, we demonstrated that ripasudil significantly lowered IOP in combined regimens with other glaucoma therapeutic agents in rabbits and monkeys. Ripasudil showed additional effects on maximum IOP lowering or prolonged the duration of IOP-lowering effects with combined administration of timolol, nipradilol, brimonidine, brinzolamide, latanoprost, latanoprost/timolol fixed combination, and dorzolamide/timolol fixed combination. These results indicate that facilitation of conventional outflow by ripasudil provides additive IOP-lowering effect with other classes of antiglaucoma agents. Ripasudil is expected to have substantial utility in combined regimens with existing agents for glaucoma treatment.

  19. Respiratory complications associated with ketamine anesthesia for ophthalmic procedures following intraocular pressure measurement in children

    Directory of Open Access Journals (Sweden)

    Lei Wu

    2014-01-01

    Full Text Available Background: We compared respiratory complications (RCs in children who received intramuscular (IM versus intravenous (IV or no ketamine for intraocular pressure (IOP measurement to test our observation that IM ketamine is associated with higher incidence of RCs. Materials and Methods: We analyzed 149 eye examinations under anesthesia with ketamine in 27 patients and 263 non-ketamine examinations under anesthesia in 81 patients using a mixed effects logistic regression model. Results: IM ketamine was strongly associated with increased odds of RCs compared to no ketamine (odds ratio (OR: 20.23, P < 0.0001 and to IV ketamine (OR: 6.78, P = 0.02, as were higher American Society of Anesthesiologists (ASA classification (OR: 2.60, P = 0.04, and the use of volatile agents (OR: 3.32, P = 0.02. Conclusion: Further studies should be conducted to confirm our observation of increased RCs with IM ketamine.

  20. The Road Ahead to Continuous 24-Hour Intraocular Pressure Monitoring in Glaucoma

    Directory of Open Access Journals (Sweden)

    Kaweh Mansouri

    2014-01-01

    Full Text Available Intraocular pressure (IOP is the only treatable risk factor for glaucoma. Yet, current glaucoma management usually relies on single IOP measurements during clinic hours despite the fact that IOP is a dynamic parameter with individual rhythms. Single IOP measurements underpin all major clinical guidelines on treatment of glaucoma. Other potentially informative parameters, such as IOP fluctuations and peak IOP, have been neglected, and effects of IOP-lowering interventions on such measures are largely unknown. The search for continuous 24-hour IOP monitoring started over 50 years ago, but only recent technological advances have provided clinician-researchers with devices for continuous IOP monitoring. Herein, we discuss innovative approaches with permanent and temporary devices for 24-hour IOP monitoring, such as a contact lens sensor. Despite being in their infancy, these devices may soon enable clinicians to use 24-hour IOP data to improve glaucoma management and reduce the glaucoma-related burden of disease.

  1. An implantable microfluidic device for self-monitoring of intraocular pressure.

    Science.gov (United States)

    Araci, Ismail E; Su, Baolong; Quake, Stephen R; Mandel, Yossi

    2014-09-01

    Glaucoma is the second most common cause of blindness in the world. It is a multifactorial disease with several risk factors, of which intraocular pressure (IOP) is a primary contributing factor. IOP measurements are used for glaucoma diagnosis and patient monitoring. IOP has wide diurnal fluctuation and is dependent on body posture, so the occasional measurements done by the eye care expert in the clinic can be misleading. Here we show that microfluidic principles can be used to develop an implantable sensor that has a limit of detection of 1 mm Hg, high sensitivity and excellent reproducibility. This device has a simple optical interface that enables IOP to be read with a smartphone camera. This sensor, with its ease of fabrication and simple design, as well as its allowance for IOP home monitoring, offers a promising approach for better care of patients with glaucoma.

  2. The road ahead to continuous 24-hour intraocular pressure monitoring in glaucoma.

    Science.gov (United States)

    Mansouri, Kaweh

    2014-04-01

    Intraocular pressure (IOP) is the only treatable risk factor for glaucoma. Yet, current glaucoma management usually relies on single IOP measurements during clinic hours despite the fact that IOP is a dynamic parameter with individual rhythms. Single IOP measurements underpin all major clinical guidelines on treatment of glaucoma. Other potentially informative parameters, such as IOP fluctuations and peak IOP, have been neglected, and effects of IOP-lowering interventions on such measures are largely unknown. The search for continuous 24-hour IOP monitoring started over 50 years ago, but only recent technological advances have provided clinician-researchers with devices for continuous IOP monitoring. Herein, we discuss innovative approaches with permanent and temporary devices for 24-hour IOP monitoring, such as a contact lens sensor. Despite being in their infancy, these devices may soon enable clinicians to use 24-hour IOP data to improve glaucoma management and reduce the glaucoma-related burden of disease.

  3. Meeting an unmet need in glaucoma: continuous 24-h monitoring of intraocular pressure.

    Science.gov (United States)

    Mansouri, Kaweh; Weinreb, Robert N

    2012-05-01

    Intraocular pressure (IOP) is a major risk factor for glaucoma and lowering IOP remains the mainstay of glaucoma treatment. Current glaucoma management usually relies on single IOP measurements during clinic hours despite the fact that the majority of glaucoma patients have their highest IOP levels outside clinic hours. The fact that these IOP peaks go largely undetected may explain why certain patients have progressive disease despite treatment. The search for devices to facilitate continuous 24-h IOP monitoring started over 50 years ago, but only recently have technological advances provided clinicians with a device for continuous IOP monitoring. We discuss the shortcomings of Goldmann Applanation Tonometry, the current gold standard for tonometry, and our experience with the SENSIMED Triggerfish®, a telemetric contact lens sensor for 24-h IOP monitoring. It may be possible to integrate 24-h continuous IOP monitoring into clinical practice, and this has the potential to contribute to the reduction of glaucoma-related vision loss.

  4. The rectenna design on contact lens for wireless powering of the active intraocular pressure monitoring system.

    Science.gov (United States)

    Cheng, H W; Jeng, B M; Chen, C Y; Huang, H Y; Chiou, J C; Luo, C H

    2013-01-01

    This paper proposed a wireless power harvesting system with micro-electro-mechanical-systems (MEMS) fabrication for noninvasive intraocular pressure (IOP) measurement on soft contact lens substructure. The power harvesting IC consists of a loop antenna, an impedance matching network and a rectifier. The proposed IC has been designed and fabricated by CMOS 0.18 um process that operates at the ISM band of 5.8 GHz. The antenna and the power harvesting IC would be bonded together by using flip chip bonding technologies without extra wire interference. The circuit utilized an impedance transformation circuit to boost the input RF signal that improves the circuit performance. The proposed design achieves an RF-to-DC conversion efficiency of 35% at 5.8 GHz.

  5. The Effect of Intraocular Pressure on the Outcome of Myopic Photorefractive Keratectomy: A Numerical Approach

    Directory of Open Access Journals (Sweden)

    Elena Lanchares

    2010-01-01

    Full Text Available Photorefractive Keratectomy (PRK is a surgical procedure widely performed to correct myopia. In this work, the effect of the intraocular pressure (IOP on the refractive correction achieved by the PRK surgery was analyzed using a numerical model. Simulations of PRK surgery at 10, 15 and 21 mmHg of IOP were performed and the post-surgical diopters were estimated. For low and medium values of IOP (10 and 15 mmHg, the computed results were close to those used by clinicians based on experience and defined without considering the IOP, while an undercorrection was predicted for the highest value of IOP (21 mmHg. From these results, we suggest that IOP should be considered in the determination of the depth of ablation, in addition to other factors such as the level of myopia or the corneal central thickness.

  6. Variation in intraocular pressure following application of tropicamide in three different dog breeds.

    Science.gov (United States)

    Taylor, Nicole R; Zele, Andrew J; Vingrys, Algis J; Stanley, Robin G

    2007-01-01

    To record intraocular pressure (IOP) of three different dog breeds following administration of one drop of 1% tropicamide. Three dog breeds -- Golden Retrievers (n = 20), Siberian Huskies (n = 20) and English Cocker Spaniels (n = 36) -- were studied. IOPs were measured using a Tonopen following corneal anesthesia with a single drop of 0.5% proxymetacaine. A drop of 0.5% tropicamide was then administered bilaterally and a second IOP measurement was taken 30 min later (postdilation). The difference between the two measurements was considered as the effect of mydriasis on IOP. Dogs had an average IOP of 14.9 +/- 3.2 mmHg, with 95% confidence limits ranging from 8 to 22 mmHg. There were significant differences between breeds (P tropicamide of canine IOP is evident.

  7. Raised intraocular pressure as a potential risk factor for visual loss in Leber Hereditary Optic Neuropathy.

    Directory of Open Access Journals (Sweden)

    Anais Thouin

    Full Text Available Leber Hereditary Optic Neuropathy (LHON is an important cause of inherited mitochondrial blindness among young adults. The majority of patients carry one of three mitochondrial DNA (mtDNA point mutations: m.3460G>A, m.11778G>A and m.14484T>C, all of which affect critical complex I subunits of the mitochondrial respiratory chain. LHON is characterised by marked incomplete penetrance, clearly implying that the mtDNA mutation is insufficient on its own to trigger retinal ganglion cell dysfunction and visual loss. In this case series of three affected patients harbouring the m.11778G>A mutation, we provide evidence suggesting that raised intraocular pressure could be a risk factor triggering visual loss in at-risk LHON carriers.

  8. Circadian modulation of sequence learning under high and low sleep pressure conditions.

    Science.gov (United States)

    Cajochen, Christian; Knoblauch, Vera; Wirz-Justice, Anna; Kräuchi, Kurt; Graw, Peter; Wallach, Dieter

    2004-05-05

    Humans are able to learn complex sequences even without conscious awareness. We have studied the repercussions of circadian phase and sleep pressure on the ability to learn structured sequences using a serial reaction time task (SRT). Sixteen young healthy volunteers were studied in a 40-h "constant posture protocol" under high sleep pressure (i.e. sleep deprivation) and low sleep pressure conditions (i.e. sleep satiation attained by multiple naps). Here we show that learning of different sequence structures improved after multiple naps, in particular after naps that followed the circadian peak of rapid-eye-movement (REM) sleep. This situation following sleep contrasted with the lack of learning without sleep. We have evidenced that the observed amelioration of learning new sequences came about by memorizing short sub-fragments ("chunks") of the sequence train. However, SRT performance did not deteriorate under high sleep pressure, despite the high level of sleepiness. Our data indicate that sequence learning is modulated by circadian phase, and the neurophysiological medium required for this type of learning is related to sleep. Copyright 2003 Elsevier B.V.

  9. Latanoprost ophthalmic solution in the treatment of open angle glaucoma or raised intraocular pressure: a review

    Directory of Open Access Journals (Sweden)

    Andrea Russo

    2009-01-01

    Full Text Available Andrea Russo, Ivano Riva, Teodoro Pizzolante, Federico Noto, Luciano QuarantaCattedra di Malattie dell’Apparato Visivo, Università degli studi di Brescia, USVD “Centro per lo studio del Glaucoma” Spedali Civili di BresciaAbstract: Latanoprost is a prostaglandin F2-alpha isopropyl ester prodrug which is rapidly hydrolyzed by esterases in the cornea to the biologically active latanoprost acid. When latanoprost is topically administered into the eye, the cornea seems to act like as a slow-release depot to the anterior segment. One hour after administration maximum concentration is found in the iris, followed by the anterior chamber and the ciliary body. Despite extensive research, controversy remains about the real mechanism of action of this drug. Immunohistochemical data have shown that the intraocular pressure (IOP reduction with topical prostaglandin F2-alpha is associated with a reduction of collagens within the uveoscleral outflow pathway. Evidence from several experimental and clinical studies suggests that latanoprost is a valuable addition first-line treatment alternatives for glaucoma, ocular hypertension and even angle-closure glaucoma. Strong points are its efficacy, which is demonstrated to be higher than that of brimonidine, dorzolamide and timolol with fewer systemic adverse effects; a convenient administration schedule; and the IOP-controlling pattern, which is relatively flat compared with timolol and dorzolamide, and enables better control in glaucoma progression, since large fluctuations may be associated with the risk of developing glaucoma in untreated ocular hypertensive subjects.Keywords: latanoprost, intraocular pressure, glaucoma, ocular hypertension

  10. A Longitudinal Study of Association between Adiposity Markers and Intraocular Pressure: The Kangbuk Samsung Health Study.

    Directory of Open Access Journals (Sweden)

    Di Zhao

    Full Text Available Intraocular pressure (IOP reduction or stabilization is the only proven method for glaucoma management. Identifying risk factors for IOP is crucial to understand the pathophysiology of glaucoma.To examine the associations of change in body mass index (BMI, waist circumference, and percent fat mass with change in intraocular pressure (IOP in a large sample of Korean adults.Cohort study of 274,064 young and middle age Korean adults with normal fundoscopic findings who attended annual or biennial health exams from January 1, 2002 to Feb 28, 2010 (577,981 screening visits.BMI, waist circumference, and percent fat mass.At each visit, IOP was measured in both eyes with automated noncontact tonometers.In multivariable-adjusted models, the average increase in IOP (95% confidence intervals over time per interquartile increase in BMI (1.26 kg/m2, waist circumference (6.20 cm, and percent fat mass (3.40% were 0.18 mmHg (0.17 to 0.19, 0.27 mmHg (0.26 to 0.29, and 0.10 mmHg (0.09 to 0.11, respectively (all P < 0.001. The association was stronger in men compared to women (P < 0.001 and it was only slightly attenuated after including diabetes and hypertension as potential mediators in the model.Increases in adiposity were significantly associated with an increase in IOP in a large cohort of Korean adults attending health screening visits, an association that was stronger for central obesity. Further research is needed to understand better the underlying mechanisms of this association, and to establish the role of weight gain in increasing IOP and the risk of glaucoma and its complications.

  11. Corneal biomechanical changes and intraocular pressure in patients with thyroid orbitopathy

    Directory of Open Access Journals (Sweden)

    Zofia Pniakowska

    2016-03-01

    Full Text Available AIM: To determine the relevance of the objective parameters addressing the altered biomechanical properties of cornea for glaucoma monitoring in patients with mild or moderate thyroid associated orbitopathy (TAO, and in healthy individuals. METHODS: Twenty-five patients with TAO (group 1 and 25 healthy adults (group 2 were included to the study. Both groups were of a similar age and the ratio women:man. For each patient, the following parameters of both eyes were measured with ocular response analyzer (ORA: corneal hysteresis (CH, corneal resistance factor (CRF, Goldmann correlated intraocular pressure (IOPg and corneal compensated intraocular pressure (IOPcc. In both groups participating in our study, all measurements were performed within minutes to reduce the diurnal effects. RESULTS: The mean age in group 1 was 56±11y and 76% were women, 24% were men. The mean age in group 2 was 64±11y and 68% were women, 32% were men. CH correlated negatively with IOPg in group 1 (r2=0.10, P0.05 and also no significant correlation in group 2 (r2=0.04, P>0.05. CRF mean value in group 2 (11.51±1.72 mm Hg was higher than in group 1 (10.85±1.45 mm Hg (P<0.05. IOPg strongly correlated with IOPcc in both groups (group 1: r2=0.79, P<0.0001; group 2: r2=0.85, P<0.0001. There was also strong correlation between CRF and CH in both populations: group 1: (r2=0.58, P<0.0001, group 2: (r2=0.41, P<0.0001. CONCLUSION: Biomechanical parameters of cornea, as quantified by CH and CRF, and measured together with IOPcc, precisely reveal glaucoma staging in TAO and thus are reliable for diagnosing and follow-up in clinical practice.

  12. Effect of High Altitude Exposure on Intraocular Pressure Using Goldmann Applanation Tonometry.

    Science.gov (United States)

    Willmann, Gabriel; Schommer, Kai; Schultheiss, Maximilian; Fischer, M Dominik; Bartz-Schmidt, Karl-Ulrich; Gekeler, Florian; Schatz, Andreas

    2017-06-01

    Willmann, Gabriel, Kai Schommer, Maximilian Schultheiss, M. Dominik Fischer, Karl-Ulrich Bartz-Schmidt, Florian Gekeler, and Andreas Schatz. Effect of high altitude exposure on intraocular pressure using Goldmann applanation tonometry. High Alt Med Biol. 18:114-120, 2017. The aim of the study was to quantify changes of intraocular pressure (IOP) during exposure to 4559 m using the state-of-the-art method of Goldmann applanation tonometry for IOP measurement and to detect correlations between IOP and acute mountain sickness (AMS) in a prospective manner. IOP was measured using a Goldmann applanation tonometer AT 900(®) (Haag-Streit, Switzerland) and central corneal thickness (CCT) with the anterior segment module of a Spectralis™ HRA+OCT(®) device (Heidelberg Engineering, Germany) at baseline and high altitude. Assessment of AMS was performed using the Lake Louise and AMS-C questionnaires, and Pearson's correlation coefficient was calculated for association between IOP and AMS. Raw IOP values at high altitude were not significantly changed compared to baseline. IOP adjusted to the increase in CCT at high altitude, which is known to alter IOP levels, showed a significant reduction for corrected IOP values on day 3 of exposure (morning -2.1 ± 1.2 mmHg; evening -2.3 ± 1.1 mmHg; p high altitude was noted. IOP showed a significant reduction of IOP levels when corrected for increased CCT values at high altitude. Furthermore, the prospective measurement of IOP is not useful in diagnosing AMS or for the prediction of more severe high altitude related illnesses as the decrease in IOP and symptoms of AMS do not correlate during altitude exposure.

  13. Does titration of mitomycin C as an adjunct to trabeculectomy significantly influence the intraocular pressure outcome?

    Directory of Open Access Journals (Sweden)

    Susan J Lee

    2008-09-01

    Full Text Available Susan J Lee1, Augusto Paranhos2, M Bruce Shields11Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, Connecticut, USA; 2Federal University of São Paulo, São Paulo, BrazilPurpose: To evaluate the benefit of titrating the concentration and exposure time of mitomycin C (MMC as an adjunct to trabeculectomy.Methods: This report consists of a retrospective study and a review of the literature. In the study, consecutive glaucoma patients were evaluated who underwent trabeculectomy with adjunctive MMC that was titrated for concentration and exposure time, based on patient’s risk factors for surgical failure. After minimum follow-up of 6 months, patients were divided into success (intraocular pressure 7–17 mmHg, hypertension (>17 mmHg and hypotony (<7 mmHg groups, which were compared with regard to MMC protocol and patient variables. The literature review included reports of trabeculectomy and adjunctive MMC with and without titration.Results: One hundred and fifty-five eyes of 155 patients were studied. There were no significant differences between the three outcome groups and MMC protocol (p > 0.05. The only significant patient variable was older age in the hypotony group (p = 0.009. The literature is conflicting regarding the value of titrating MMC as an adjunct in trabeculectomy.Conclusion: The outcome of trabeculectomy with adjunctive MMC appears to represent a complex interaction of patient and surgical variables. While there is some support for a benefit of titrating MMC according to individual patient variables, there is inadequate evidence at the present time to claim superiority for any MMC protocol, with or without titration.Keywords: glaucoma surgery, trabeculectomy, mitomycin C, intraocular pressure

  14. The effect of laryngeal mask airway insertion on intraocular pressure measurement in children receiving general anesthesia.

    Science.gov (United States)

    Watts, Patrick; Lim, May Kim; Gandhewar, Ravikiran; Mukherjee, Aychut; Wintle, Richard; Armstrong, Trevor; Zatman, Tahsin; Jones, Rhys; Al Madfai, Hasan

    2007-10-01

    To study changes in intraocular pressure (IOP) in children while under general anesthesia before and after laryngeal mask airway (LMA) insertion. Prospective, comparative study. IOP was measured in children after induction and one minute after LMA insertion. Children younger than 16 years who were scheduled to undergo elective ophthalmic surgery while receiving a general anesthetic were included. Children with a history of glaucoma or previous intraocular surgery were excluded. Data were collected on the age of the child, IOP, heart rate (HR), end tidal CO2, and blood pressure (BP) before and after LMA insertion. Sixty-six children with a mean age of 5.5 +/- 3.6 years (range, four months to 16 years) were included in the study. The mean IOP was 13.6 +/- 3.9 mm Hg and 13.6 +/- 3.6 mm Hg in right and left eyes, respectively, before LMA insertion and 15.5 +/- 3.8 mm Hg and 15.2 +/- 3.8 mm Hg in right and left eyes, respectively, after LMA insertion (P = .001). A decrease in BP was significantly associated with an increase in IOP (P = .008), and the interaction between the change in the BP, HR, and CO2 affected the change in IOP measured after insertion of the LMA (P = .04). There was no correlation between the age of the child and the change in IOP measured after insertion of the LMA. In our study, a small but significantly higher IOP was found after LMA insertion than before. It is recommended that the measurement of IOP in children receiving a general anesthetic is carried out before the insertion of the LMA.

  15. A Longitudinal Study of Association between Adiposity Markers and Intraocular Pressure: The Kangbuk Samsung Health Study.

    Science.gov (United States)

    Zhao, Di; Kim, Myung Hun; Pastor-Barriuso, Roberto; Chang, Yoosoo; Ryu, Seungho; Zhang, Yiyi; Rampal, Sanjay; Shin, Hocheol; Kim, Joon Mo; Friedman, David S; Guallar, Eliseo; Cho, Juhee

    2016-01-01

    Intraocular pressure (IOP) reduction or stabilization is the only proven method for glaucoma management. Identifying risk factors for IOP is crucial to understand the pathophysiology of glaucoma. To examine the associations of change in body mass index (BMI), waist circumference, and percent fat mass with change in intraocular pressure (IOP) in a large sample of Korean adults. Cohort study of 274,064 young and middle age Korean adults with normal fundoscopic findings who attended annual or biennial health exams from January 1, 2002 to Feb 28, 2010 (577,981 screening visits). BMI, waist circumference, and percent fat mass. At each visit, IOP was measured in both eyes with automated noncontact tonometers. In multivariable-adjusted models, the average increase in IOP (95% confidence intervals) over time per interquartile increase in BMI (1.26 kg/m2), waist circumference (6.20 cm), and percent fat mass (3.40%) were 0.18 mmHg (0.17 to 0.19), 0.27 mmHg (0.26 to 0.29), and 0.10 mmHg (0.09 to 0.11), respectively (all P < 0.001). The association was stronger in men compared to women (P < 0.001) and it was only slightly attenuated after including diabetes and hypertension as potential mediators in the model. Increases in adiposity were significantly associated with an increase in IOP in a large cohort of Korean adults attending health screening visits, an association that was stronger for central obesity. Further research is needed to understand better the underlying mechanisms of this association, and to establish the role of weight gain in increasing IOP and the risk of glaucoma and its complications.

  16. A longitudinal study of age-related changes in intraocular pressure: the Kangbuk Samsung Health Study.

    Science.gov (United States)

    Zhao, Di; Kim, Myung Hun; Pastor-Barriuso, Roberto; Chang, Yoosoo; Ryu, Seungho; Zhang, Yiyi; Rampal, Sanjay; Shin, Hocheol; Kim, Joon Mo; Friedman, David S; Guallar, Eliseo; Cho, Juhee

    2014-09-02

    To examine the longitudinal association between age and intraocular pressure (IOP) in a large sample of Korean men and women. We conducted a prospective cohort study of 274,064 young and middle-aged Korean adults with normal fundoscopic findings, following them from January 1, 2002, to February 28, 2010. Health exams were scheduled annually or biennially. At each visit, IOP was measured in both eyes using automated noncontact tonometers. The longitudinal change in IOP with age was evaluated using three-level mixed models for longitudinal paired-eye data, accounting for correlations between paired eyes and repeated measurements over time. In fully adjusted models, the average longitudinal change in IOP per 1-year increase in age was -0.065 mm Hg (95% confidence interval [CI] -0.068 to -0.063), with marked sex differences (P < 0.001). In men, the average annual IOP change was -0.093 mm Hg (95% CI -0.096 to -0.091) throughout follow-up. In women, the average annual IOP change was -0.006 mm Hg (95% CI -0.010 to -0.003), with a relatively flat association in the age range of 30 to 59 years and more marked annual decreases at younger and older ages. Intraocular pressure was inversely associated with age in a large cohort of Korean adults attending health-screening visits. For men, this inverse association was observed throughout the entire age range, while for women it was evident only in younger (<30 years of age) and older (≥60 years of age) women, with no association in women aged 30 to 59. Further research is needed to better understand the underlying mechanisms and to reconsider cutoffs for defining high IOP by age and sex groups in Asian populations. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  17. Glaucoma Surgery Calculator: Limited Additive Effect of Phacoemulsification on Intraocular Pressure in Ab Interno Trabeculectomy.

    Science.gov (United States)

    Neiweem, Ashley E; Bussel, Igor I; Schuman, Joel S; Brown, Eric N; Loewen, Nils A

    2016-01-01

    To compare intraocular pressure (IOP) reduction and to develop a predictive surgery calculator based on the results between trabectome-mediated ab interno trabeculectomy in pseudophakic patients versus phacoemulsification combined with trabectome-mediated ab interno trabeculectomy in phakic patients. This observational surgical cohort study analyzed pseudophakic patients who received trabectome-mediated ab interno trabeculectomy (AIT) or phacoemulsification combined with AIT (phaco-AIT). Follow up for less than 12 months or neovascular glaucoma led to exclusion. Missing data was imputed by generating 5 similar but non-identical datasets. Groups were matched using Coarsened Exact Matching based on age, gender, type of glaucoma, race, preoperative number of glaucoma medications and baseline intraocular pressure (IOP). Linear regression was used to examine the outcome measures consisting of IOP and medications. Of 949 cases, 587 were included consisting of 235 AIT and 352 phaco-AIT. Baseline IOP between groups was statistically significant (p≤0.01) in linear regression models and was minimized after Coarsened Exact Matching. An increment of 1 mmHg in baseline IOP was associated with a 0.73±0.03 mmHg IOP reduction. Phaco-AIT had an IOP reduction that was only 0.73±0.32 mmHg greater than that of AIT. The resulting calculator to determine IOP reduction consisted of the formula -13.54+0.73 × (phacoemulsification yes:1, no:0) + 0.73 × (baseline IOP) + 0.59 × (secondary open angle glaucoma yes:1, no:0) + 0.03 × (age) + 0.09 × (medications). This predictive calculator for minimally invasive glaucoma surgery can assist clinical decision making. Only a small additional IOP reduction was observed when phacoemulsification was added to AIT. Patients with a higher baseline IOP had a greater IOP reduction.

  18. The Aachen-keratoprosthesis--a flexible KPro that permits intraocular pressure measurement.

    Science.gov (United States)

    Krug, A; Kompa, S; Schrage, N F

    2002-03-01

    Postoperative glaucoma is one of the major complications observed in patients with keratoprostheses (KPro). The optical components of the majority of KPros are rigid and inflexible, which prevents indirect tonometry by common methods. This study confirms that the Aachen-KPro allows measurements of intraocular pressure (IOP) due to its flexible optical part with a modified Schiotz tonometer. The Aachen-KPro was placed in a special chamber where pressure can be generated and monitored by a transducer. Measurements were taken by common ophthalmologic methods. The results were compared to the initial pressure values in the chamber. With the Goldmann tonometer, the Tono-Pen and the topography system (Technomed), no significant pressure changes could be observed. The results of the Schiotz tonometer were promising. It was slightly modified and standard curves with different weights could be obtained. With a modified Schiotz tonometer, it is possible to detect elevated IOPs. Modifying this common instrument is inexpensive and can be easily performed. This advantage of the Aachen-KPro permits early management of postoperative high tension glaucoma.

  19. Effect of Uterine Fundal Pressure on Maternal Intraocular Pressure in Cesarean Delivery: Comparison of Regional and General Anesthesia.

    Science.gov (United States)

    Kurtay, Aysun; Ozayar, Esra; Gulec, Handan; Yildiz, Gokhan; Turkyilmaz, Esra; Yildiz, Zennure; Horasanli, Eyup

    2017-08-01

    To evaluate the intraocular pressure (IOP) changes accompanying fundal pressure during a cesarean-section procedure under both regional and general anesthesia. In total, 60 women scheduled for elective cesarean section, none of them diagnosed with ocular problems, were enrolled in the study. Patients underwent cesarean section under either general (group G, n=30) or regional anesthesia (group S, n=30) according to their choice. IOP was measured with a Tono-Pen before (T1) and after (T2) application of anesthesia, during fundal pressure (T3), and after the birth of the baby (T4). Heart rate as well as systolic, diastolic, and mean arterial pressure were recorded during the procedure. There was no significant difference in IOP between the groups (P>0.05). In group S, IOP at T3 was significantly higher than at all other timepoints (Ppressure was significantly lower in group S at all timepoints except T1. In conclusion, fundal pressure may significantly increase the IOP, but the choice of anesthetic technique may not have any effect on IOP.

  20. Effect of intravenous metoclopramide on intraocular pressure: A prospective, randomized, double-blind, placebo-controlled study

    Directory of Open Access Journals (Sweden)

    Sudheera K

    2008-01-01

    Full Text Available Background: Prevention of rise in intraocular pressure (IOP is essential in patients undergoing surgery for perforated eye injuries. Metoclopramide, a prokinetic agent, is commonly used to hasten gastric emptying in emergency surgeries. Aim: To study the change in IOP after intravenous metoclopramide and to study the influence of metoclopramide on change in IOP after succinylcholine and tracheal intubation. Settings and Design: A randomized, double-blind, placebo-controlled study of 60 patients undergoing non-ophthalmic elective surgery. Materials and Methods: Sixty American Society of Anesthesiologists (ASA I adult patients were randomly assigned to receive normal saline (Group C or metoclopramide 10 mg (Group M 30 min before the induction of anesthesia. Thiopentone was used for induction and succinylcholine for tracheal intubation. Intraocular pressure was measured in both the eyes pre and post drug treatment and succinylcholine and tracheal intubation using Perkins applanation tonometer. Statistical Analysis: Student′s t-test and repeated measures ANOVA were used. A P value < 0.05 was considered as significant. Results: Intraocular pressure was consistently lower in Group M than in Group C after the test drug, though the difference was not statistically significant. Intraocular pressure decreased significantly after administration of thiopentone and increased significantly in Groups C and M after tracheal intubation ( P < 0.01. Intraocular pressure was comparable between the groups at all the times. Conclusions: Metoclopramide does not cause a clinically significant change in IOP nor does it influence the changes in IOP during anesthesia and tracheal intubation. Metoclopramide shows a trend towards decrease in IOP, though clinically insignificant. Therefore metoclopramide can be used to promote gastric emptying in patients with perforated eye injury.

  1. Circadian variation of blood pressure in patients with chronic renal failure on continuous ambulatory peritoneal dialysis

    DEFF Research Database (Denmark)

    Clausen, P; Feldt-Rasmussen, B; Ladefoged, Jens

    1995-01-01

    a non-invasive ambulatory blood pressure recorder. Average 24-h blood pressure was significantly higher in the group of CAPD patients than in the group of healthy controls, i.e. 141 +/- 22/82 +/- 8 mmHg (systolic and diastolic blood pressure +/- SD) vs. 126 +/- 18/80 +/- 7, p ...The circadian pattern of blood pressure variation was investigated in 10 patients with advanced chronic renal failure on continuous ambulatory peritoneal dialysis (CAPD) and in an age-matched group of controls without renal disease with similar office blood pressure level. Monitoring was done using...... of abnormal 24-h blood pressure profiles among CAPD patients. In the group of controls these profiles were in accordance with the established normal pattern, whereas nocturnal blood pressure reductions were significantly less pronounced in the patient group. The reduction +/- SD in the mean arterial blood...

  2. Differences in circadian time structure of diastolic blood pressure between diabetes mellitus and essential hypertension

    Directory of Open Access Journals (Sweden)

    Matteucci Elena

    2012-12-01

    Full Text Available Abstract Background Abnormal circadian blood pressure patterns have been associated with cardiovascular disease in diabetes mellitus. We have described that the acrophase of diastolic blood pressure (DBP registered in type 1 diabetes (T1D patients was significantly earlier than normal and DBP ecphasia was more pronounced in patients with lower heart rate variability during deep breathing. The aim of this study was to compare the circadian rhythm characteristics of BP among different groups: normotensive (NT control subjects, patients affected by T1D and type 2 diabetes (T2D, and patients with essential hypertension (HT. Findings We retrospectively evaluated ambulatory blood pressure monitoring records in 30 NT, 20 T1D, 20 T2D, 20 HT whose fasting plasma glucose and HbA1c were contemporaneously measured. The four groups were well-matched regarding age, gender, and BMI. Systolic blood pressure (SBP and DBP midline-estimating statistic of rhythm were higher in T1D, T2D, and HT groups. DBP ecphasia was present only in the diabetic individuals: the acrophase of DBP occurred four hours earlier than normal in T1D group, whereas two hours earlier in T2D group. In a multiple regression analysis, only HbA1c and SBP acrophase were statistically significant correlates of DBP acrophase. Conclusions People with diabetes mellitus, both type 1 and type 2, have their circadian acrophase of DBP occurring 2–4 hours earlier than normotensive and hypertensive subjects. Altered circadian timing of DBP, potential trigger of cardiovascular events, seems to be a distinguishing feature of diabetes mellitus and correlates with the previous 2–3 months of glycaemic control.

  3. Movement of retinal vessels toward the optic nerve head after increasing intraocular pressure in monkey eyes with experimental glaucoma.

    Science.gov (United States)

    Kuroda, Atsumi; Enomoto, Nobuko; Ishida, Kyoko; Shimazawa, Masamitsu; Noguchi, Tetsuro; Horai, Naoto; Onoe, Hirotaka; Hara, Hideaki; Tomita, Goji

    2017-09-01

    A shift or displacement of the retinal blood vessels (RBVs) with neuroretinal rim thinning indicates the progression of glaucomatous optic neuropathy. In chronic open angle glaucoma, individuals with RBV positional shifts exhibit more rapid visual field loss than those without RBV shifts. The retinal vessels reportedly move onto the optic nerve head (ONH) in response to glaucoma damage, suggesting that RBVs are pulled toward the ONH in response to increased cupping. Whether this phenomenon only applies to RVBs located in the vicinity or inside the ONH or, more generally, to RBVs also located far from the ONH, however, is unclear. The aim of this study was to evaluate the movement of RBVs located relatively far from the ONH edge after increasing intraocular pressure (IOP) in an experimental monkey model of glaucoma. Fundus photographs were obtained in 17 monkeys. High IOP was induced in the monkeys by laser photocoagulation burns applied uniformly with 360° irradiation around the trabecular meshwork of the left eye. The right eye was left intact and used as a non-treated control. Considering the circadian rhythm of IOP, it was measured in both eyes of each animal at around the same time-points. Then, fundus photographs were obtained. Using Image J image analysis software, an examiner (N.E.) measured the fundus photographs at two time-points, i.e. before laser treatment (time 1) and the last fundus photography after IOP elevation (time 2). The following parameters were measured (in pixels): 1) vertical diameter of the ONH (DD), 2) distance from the ONH edge to the first bifurcation point of the superior branch of the central retinal vein (UV), 3) distance from the ONH edge to the first bifurcation point of the inferior branch of the central retinal vein (LV), 4) ONH area, and 5) surface area of the cup of the ONH. We calculated the ratios of UV to DD (UV/DD), LV to DD (LV/DD), and the cup area to disc area ratio (C/D). The mean UV/DD at time 1 (0.656 ± 0.233) was

  4. Space obstructive syndrome: intracranial hypertension, intraocular pressure, and papilledema in space.

    Science.gov (United States)

    Wiener, Thomas C

    2012-01-01

    Humans undergo several consistent and measurable changes of fluid distribution and regulation in the course of adapting to microgravity. Recently, a syndrome of objective findings has been described by Mader et al. associated with long-duration missions, including hyperopic shifts, mildly elevated intracranial pressure, papilledema, globe flattening, choroidal folds, and other anatomic findings. Experience with venous obstructive lesions leads the author to propose a primary obstructive process, unique to or exacerbated by microgravity, acting at the level of the proximal internal jugular veins, termed Space Obstructive Syndrome (SOS). Literature, anatomy, and ultrasound observations revealed four major potential compression zones of the internal jugular vein, with Zone I between the sternocleidomastoid muscle and the carotid artery as the primary area of compression, both in 1 G in an upright position and in microgravity. Internal jugular vein compression, along with loss of gravitationally induced cranial outflow of blood in the vertebral veins and collaterals, may lead to intracranial venous hypertension with resultant facial/head and upper airway swelling, increased intraocular pressure, intracranial hypertension, and papilledema. Further study and proof of concept will necessitate ultrasound, Doppler flow study, and internal jugular vein pressure measurements on orbit in the International Space Station. If proven, SOS will give researchers opportunity for study and development of mitigation strategies such as artificial gravity systems.

  5. Intraocular pressure control of a novel glaucoma drainage device - in vitro and in vivo studies.

    Science.gov (United States)

    Cui, Li-Jun; Li, Di-Chen; Liu, Jian; Zhang, Lei; Xing, Yao

    2017-01-01

    To evaluate the intraocular pressure (IOP) control of an artificial trabeculum drainage system (ATDS), a newly designed glaucoma drainage device, and postoperative complications in normal rabbit eyes. Pressure drops in air and fluid of 30 ATDS were measured after being connected to a closed manometric system. Twenty of them were then chosen and implanted randomly into the eyes of 20 rabbits. Postoperative slit-lamp, gonioscopic examination and IOP measurements were recorded periodically. Ultrasound biomicroscopy and B-scan ultrasonography were also used to observe the complications. Eyes were enucleated on day 60. Pressure drops of 4.6-9.4 mm Hg were obtained at physiological aqueous flow rates in the tests in vitro. The average postoperative IOP of the experimental eyes (11.6-12.8 mm Hg) was lower than the controls significantly (Pdevices were devoid of obstructions in all specimens examined and a thin fibrous capsule was found around the endplate. ATDS reduce IOP effectively. However, further studies on the structure are needed to reduce complications.

  6. Association between corneal hysteresis and the magnitude of intraocular pressure decrease after cataract surgery.

    Science.gov (United States)

    Deol, Madhvi; Ehrlich, Joshua R; Shimmyo, Mitsugu; Radcliffe, Nathan M

    2015-06-01

    To evaluate the relationship between baseline corneal hysteresis (CH) and the change in intraocular pressure (IOP) before and after cataract extraction in patients without glaucoma. Private practice, New York City, New York, USA. Retrospective cohort study. Charts of consecutive patients who had phacoemulsification cataract extraction with posterior chamber intraocular lens implantation were analyzed. All included patients had preoperative and postoperative measurements with the Ocular Response Analyzer 2 to 4 months and 10 to 12 months postoperatively. Data collected included age, baseline CH, baseline central corneal thickness (CCT), and IOP. Thirty nine (65 eyes) of the 230 patients met the inclusion criteria. The mean patient age was 70.8 years ± 8.6 (SD). The mean preoperative, 2- to 4-month and 10- to 12- month postoperative IOP values were 14.8 ± 3.5 mm Hg, 11.9 ± 3.4 mm Hg, and 12.6 ± 3.1 mm Hg, respectively (P < .05 for comparisons with preoperative IOP). The baseline CH was not predictive of the IOP reduction at 2 to 4 months (β = -0.3; 95% confidence interval [CI], -0.7 to 0.01; P = .06). However, the baseline CH (but not the baseline CCT) was statistically associated with the magnitude of IOP reduction at 10 to 12 months when controlling for patient age (β = -0.5; 95% CI, -0.8 to -0.1; P = .01). A low baseline CH was associated with a larger magnitude of IOP reduction after cataract extraction. Dr. Radcliffe is a consultant to Reichert Technologies and Glaukos Corp.; a consultant to and speaker for Allergan, Inc., Alcon Laboratories, Inc., Iridex Corp., Merge Healthcare, Carl Zeiss Meditec AG; and a speaker for Merck Pharmaceuticals. No other author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  7. Effect of cataract surgery on intraocular pressure in supine and lateral decubitus body postures.

    Science.gov (United States)

    Park, Ji-Hye; Yoo, Chungkwon; Song, Jong-Suk; Lin, Shan C; Kim, Yong Yeon

    2016-10-01

    To investigate the effect of phacoemulsification on intraocular pressure (IOP) in different recumbent body postures including supine and lateral decubitus (LD) positions. This prospective, observational study included patients who had no glaucoma and who had planned to undergo phacoemulsification and intraocular lens implantation in one eye. Before and 1 month after cataract surgery, IOP was measured in both eyes using the Tono-Pen AVIA. We measured IOP in the sitting, supine, and LD (with the operated eye placed on the lower side) positions. IOP was measured 10 min after assuming each position in a randomized sequence. The Wilcoxon signed-rank test was used to compare the IOP changes before and 1 month after phacoemulsification in all postures. Twenty-nine patients participated in this study. Postoperative IOP was lower than the preoperative IOP when measured by Goldmann applanation tonometry in the sitting position (13.8 ± 1.9 mmHg vs. 12.6 ± 2.1 mmHg, P = 0.007). The postoperative IOP was lower than the preoperative IOP for the supine and LD positions. The average IOP reduction of the operated eye was 0.6 mmHg, 1.7 mmHg, and 3.0 mmHg in the sitting, supine, and LD positions, respectively (sitting vs. supine, P = 0.048; sitting vs. LD, P = 0.001; supine vs. LD, P = 0.028). In the nonoperated eye, IOP did not change significantly after surgery (all P > 0.05). Cataract surgery lowered IOP in the sitting position as well as in the supine and LD positions. Such postoperative IOP reductions were greater in the recumbent positions than in the sitting position.

  8. Effects of tramadol on tear production, intraocular pressure, and pupil size in dogs: clinical study

    Directory of Open Access Journals (Sweden)

    Thaís Ruiz

    2015-04-01

    Full Text Available This study aimed to evaluate the effects of tramadol on tear production, intraocular pressure (IOP and pupil diameter (PD in healthy dogs. Dogs were randomly assigned to receive 4mg kg-1 (n=11 and 6mg kg-1 (n=11 of tramadol hydrochloride intramuscularly. Tear production (Schirmer tear test, STT-1, IOP (applanation tonometry and the PD (electronic pachymetry were assessed before, 30 and 60 minutes after administration of tramadol. Data were compared by analysis of variance for repeated measures (P<0.05. Parameters evaluated before, at 30 and 60min, in dogs treated with 4 and 6mg kg-1, were respectively: (STT-1 22.50±3.38, 21.14±3.94 and 21.09±2.99mm min-1; and 23.05±3.73,22.64±3.76 and 22.82±3.25mm min-1. (IOP 18.14±2.68, 17.68±2.59 and 18.23±3.84mmHg; and 19.05±2.27, 18.91±2.74 and 17.64±2.34mmHg. (PD 6.71±0.65, 7.22±1.42 and 6.90±1.39mm; and 6.25±1.08, 6.80±1.27 and 6.49±0.90mm. All parameters evaluated did not change significantly among time points and dose regimen. Based on the conditions under which the experiments were conducted, tramadol did not affect tear production, IOP and PD in dogs, and could be used as a preoperative analgesic for intraocular surgery and pain control for any cause in patients affected by uveitis, glaucoma and keratoconjunctivitis sicca

  9. Intraocular pressure in schizophrenic patients treated with psychiatric medications Pressão intra-ocular em pacientes esquizofrênicos tratados com medicações psiquiátricas

    Directory of Open Access Journals (Sweden)

    Valéria Barreto Novais e Souza

    2008-10-01

    Full Text Available PURPOSE: In order to assess the occurrence of adverse ocular effects of antipsychotic drugs, we sought to evaluate intraocular pressure of schizophrenic patients treated with psychiatric medications. METHODS: Twenty-eight outpatients with DSM-IV diagnosis of schizophrenia who met both the inclusion and exclusion criteria were submitted to an ophthalmic evaluation for ocular abnormalities which included intraocular pressure measurement with Goldmann applanation tonometry. RESULTS: Raised intraocular pressure was found in three patients (11%. Abnormality in cup-disc ratio was seen in only one patient with cup-disc ratio asymmetry of 0.4. All these four patients were taking only ziprasidone. CONCLUSIONS: Patients using ziprasidone were found to have abnormalities in both intraocular pressure and cup-disc ratio.OBJETIVO: Para avaliar a ocorrência de efeitos adversos oculares dos antipsicóticos, buscamos avaliar a pressão intra-ocular em pacientes esquizofrênicos tratados com medicações psiquiátricas. MÉTODOS: Vinte e oito pacientes tratados ambulatorialmente com diagnóstico de esquizofrenia segundo o DSM-IV que preencheram os critérios de inclusão e exclusão foram submetidos a uma avaliação oftalmológica para pesquisa de alterações oculares que incluiu a medida da pressão intra-ocular com tonometria de aplanação de Goldmann. RESULTADOS: Pressão intra-ocular aumentada foi encontrada em 3 pacientes (11%. Anormalidade na escavação do disco óptico foi observada em apenas um paciente com assimetria de escavação de 0,4. Todos esses quatro pacientes estavam usando apenas ziprasidona. CONCLUSÕES: Pacientes em uso de ziprasidona apresentaram anormalidades na pressão intra-ocular e na escavação do disco óptico.

  10. Assessing the True Intraocular Pressure in the Non-human Primate.

    Science.gov (United States)

    McAllister, Faith; Harwerth, Ronald; Patel, Nimesh

    2018-02-01

    For glaucoma patients, high intraocular pressure (IOP) is a risk factor for progressive neuropathy. Similarly, animal models used to study the disease are based on an experimental elevation of IOP. Thus, accurate IOP measurements are important in characterizing experimental models and resulting effects. The purpose of the present study was to investigate IOP measurements in a non-human primate model of experimental glaucoma by comparing clinical tonometry (Tono-Pen and TonoVet) to the true IOP from intracameral manometry. A total of 17 rhesus macaque eyes from 12 animals were used for this study. Eleven eyes had no previous experimental intervention, whereas six eyes were at varying stages of laser-induced experimental glaucoma. IOPs were adjusted by inserting a needle in the anterior chamber that was attached to a pressure transducer and syringe pump system. The anterior chamber IOP was adjusted to values between 10 and 50 mmHg and corresponding measures with Tono-Pen and TonoVet were taken. The IOPs by TonoVet and Tono-Pen were linearly related over the range of pressures tested (slope = 0.68 normal/healthy and 0.72 experimental glaucoma). For the most, TonoVet measures overestimated IOP at all anterior chamber pressure settings (mean difference of 3.17 mmHg, 95% CI 12.53 to -4.74 normal and 3.90 mmHg, 95% CI 12.90 to -6.53 experimental glaucoma). In contrast, Tono-Pen measures overestimated IOP at lower IOPs and underestimated at higher IOP (slope = -0.26 normal and -0.21 experimental glaucoma). The TonoVet and Tono-Pen tonometers that are often used to assess IOP in both clinical and experimental settings generally reflect the status of IOP, but the results from this study suggest that the instruments need calibration with true anterior chamber pressure for accurate measures in experimental models of glaucoma.

  11. Intraocular pressure dynamics with prostaglandin analogs: a clinical application of water-drinking test

    Directory of Open Access Journals (Sweden)

    Özyol P

    2016-07-01

    Full Text Available Pelin Özyol,1 Erhan Özyol,1 Ercan Baldemir2 1Ophthalmology Department, 2Biostatistics Department, Faculty of Medicine, Mugla Sitki Kocman University, Mugla, Turkey Aim: To evaluate the clinical applicability of the water-drinking test in treatment-naive primary open-angle glaucoma patients. Methods: Twenty newly diagnosed primary open-angle glaucoma patients and 20 healthy controls were enrolled in this prospective study. The water-drinking test was performed at baseline and 6 weeks and 3 months after prostaglandin analog treatment. Peak and fluctuation of intraocular pressure (IOP measurements obtained with the water-drinking test during follow-up were analyzed. Analysis of variance for repeated measures and paired and unpaired t-tests were used for statistical analysis. Results: The mean baseline IOP values in patients with primary open-angle glaucoma were 25.1±4.6 mmHg before prostaglandin analog treatment, 19.8±3.7 mmHg at week 6, and 17.9±2.2 mmHg at month 3 after treatment. The difference in mean baseline IOP of the water-drinking tests was statistically significant (P<0.001. At 6 weeks of prostaglandin analog treatment, two patients had high peak and fluctuation of IOP measurements despite a reduction in baseline IOP. After modifying treatment, patients had lower peak and fluctuation of IOP values at month 3 of the study. Conclusion: Peak and fluctuation of IOP in response to the water-drinking test were lower with prostaglandin analogs compared with before medication. The water-drinking test can represent an additional benefit in the management of glaucoma patients, especially by detecting higher peak and fluctuation of IOP values despite a reduced mean IOP. Therefore, it could be helpful as a supplementary method in monitoring IOP in the clinical practice. Keywords: glaucoma, intraocular pressure, water-drinking test, prostaglandin analog, intra­ocular pressure fluctuation

  12. Computational modeling of fluid flow and intra-ocular pressure following glaucoma surgery.

    Directory of Open Access Journals (Sweden)

    Bruce S Gardiner

    Full Text Available BACKGROUND: Glaucoma surgery is the most effective means for lowering intraocular pressure by providing a new route for fluid to exit the eye. This new pathway is through the sclera of the eye into sub-conjunctival tissue, where a fluid filled bleb typically forms under the conjunctiva. The long-term success of the procedure relies on the capacity of the sub-conjunctival tissue to absorb the excess fluid presented to it, without generating excessive scar tissue during tissue remodeling that will shut-down fluid flow. The role of inflammatory factors that promote scarring are well researched yet little is known regarding the impact of physical forces on the healing response. METHODOLOGY: To help elucidate the interplay of physical factors controlling the distribution and absorption of aqueous humor in sub-conjunctival tissue, and tissue remodeling, we have developed a computational model of fluid production in the eye and removal via the trabecular/uveoscleral pathways and the surgical pathway. This surgical pathway is then linked to a porous media computational model of a fluid bleb positioned within the sub-conjunctival tissue. The computational analysis is centered on typical functioning bleb geometry found in a human eye following glaucoma surgery. A parametric study is conducted of changes in fluid absorption by the sub-conjunctival blood vessels, changes in hydraulic conductivity due to scarring, and changes in bleb size and shape, and eye outflow facility. CONCLUSIONS: This study is motivated by the fact that some blebs are known to have 'successful' characteristics that are generally described by clinicians as being low, diffuse and large without the formation of a distinct sub-conjunctival encapsulation. The model predictions are shown to accord with clinical observations in a number of key ways, specifically the variation of intra-ocular pressure with bleb size and shape and the correspondence between sites of predicted maximum

  13. Effects of inner materials on the sensitivity and phase depth of wireless inductive pressure sensors for monitoring intraocular pressure

    Science.gov (United States)

    Jang, Cheol-In; Shin, Kyeong-Sik; Kim, Mi Jeung; Yun, Kwang-Seok; Park, Ki Ho; Kang, Ji Yoon; Lee, Soo Hyun

    2016-03-01

    In this research, we developed wireless, inductive, pressure sensors with high sensitivity and investigated the effects of the inner materials (copper or ferrite) on the performance of the sensors. The proposed sensor is comprised of two parts, i.e., the top and the bottom parts. The top part includes a micro coil and a capacitor for the wireless transfer of data, and the bottom part includes the inner materials and a thick or thin flexible membrane to induce changes in the inductance. An anchor is used to assemble the top and bottom parts. The behavior of the sensor with copper was based on the eddy current effect, and, as the pressure increased, its resonance frequency increased, while its phase depth decreased exponentially. The principle of the sensor with ferrite was related to the effective permeability between a ferrite and a coil, and its response was the opposite of that with copper, i.e., as the pressure increased, the resonance frequency decreased linearly, and the phase depth increased linearly. These different operational mechanisms can be explained by the changes in the equations of inductance presented in this paper. After characterizing four different types of inductive pressure sensors in ambient air, one type of inductive pressure sensor was used to monitor the intraocular pressure (IOP) of a rabbit's eye as a biomedical application. The results showed that, in the animal tests, the measured responsivity and sensitivity were 16.7 kHz/mmHg and 1340 ppm/mmHg, respectively. These data indicate that the proposed sensor is a good candidate for monitoring IOP.

  14. Metabolic syndrome: a risk factor for high intraocular pressure in the Israeli population

    Directory of Open Access Journals (Sweden)

    Tamara Wygnanski-Jaffe

    2015-04-01

    Full Text Available AIM: To evaluate the association among elevated intraocular pressure (IOP, the metabolic syndrome (MetS, body mass index (BMI, and some of their components in the Israeli population. METHODS: We retrospectively reviewed the charts of 12 747 soldiers of the Israeli Defense Forces, aged 35y or older, who underwent a routine periodical medical examination between 1991 and 2004. None of the subjects received medical treatment for either glaucoma or ocular hypertension. High IOP (>21 mm Hg was correlated with age, sex, arterial blood pressure, total blood cholesterol levels, triglyceride levels, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, smoking , BMI and MetS. RESULTS: A statistically significant difference was found between the IOP of subjects with a low risk and higher risk for the development of MetS (P<0.0001 for males, P=0.0026 for females. A statistically significant positive correlation was found in male subjects between high BMI and elevated IOP (r=0.11677, P<0.0001. CONCLUSION: MetS and BMI were significantly more prevalent in subjects with increased IOP levels. We suggest that both should be taken into consideration in the assessment of glaucoma suspects.

  15. Spectral analysis of intraocular pressure pulse wave in ocular hypertensive and primary open angle glaucoma patients

    Directory of Open Access Journals (Sweden)

    Marija M Bozic

    2016-01-01

    Full Text Available Context: In attempt to find an alternative way to determine conversion from ocular hypertension to primary open angle glaucoma (POAG (besides visual field and optic disc changes, we analyzed intraocular pressure (IOP pulse wave in spectral domain. Aims: The aim of this study was to test the potential differences in spectral content of IOP pulse wave between ocular hypertension and POAG patients, which could indicate conversion. Settings and Design: Cross-sectional study designed to test the differences in the spectral content of pressure pulse wave between nontreated ocular hypertensive and nontreated, freshly diagnosed POAG patients. Methods: The total of 40 eyes of 40 subjects was included: 20 previously untreated ocular hypertensive patients, and 20 previously untreated POAG patients. Continuous IOP measuring gained by dynamic contour tonometry was submitted to fast Fourier transform signal analysis and further statistical data processing. Statistics Analysis Used: Ocular and systemic characteristics of the tested subjects were compared by analysis of variance appropriate for this study design. A P < 0.05 was considered to be statistically significant. Results: Higher spectral components of the IOP pulse wave was discerned up to the fifth harmonic in both of the tested groups. No statistically significant differences were found in any of the tested harmonic amplitudes. Conclusions: There are no differences in the spectral content of IOP pulse wave between ocular hypertensive and primary open angle glaucoma patients which could be indicative for conversion.

  16. Repeatability and Reproducibility of Intraocular Pressure and Dynamic Corneal Response Parameters Assessed by the Corvis ST

    Directory of Open Access Journals (Sweden)

    Bernardo T. Lopes

    2017-01-01

    Full Text Available Purpose. To assess the repeatability and reproducibility of dynamic corneal response parameters measured by the Corvis ST (Oculus, Wetzlar, Germany. Methods. One eye randomly selected from 32 healthy volunteers was examined by the Corvis ST. Three different devices were used in an alternated random order for taking three measurements at each device in each subject. Standard intraocular pressure (IOP, the biomechanical-compensated IOP (bIOP, and DCR parameters were evaluated. The within-subject standard deviation (ζw and coefficient of variation (CV were assessed. Results. Regarding pressure indices, the ζw was below 1 mmHg for repeatability (0.98 for IOP and 0.89 for bIOP and the CV was 6.6% for IOP and 6.1% for bIOP. For reproducibility, the ζw was around 1 mmHg (1.12 for IOP and 1.05 for bIOP and the CV was 7.6% for IOP and 7.1% for bIOP. Most of DCR indices presented CV for repeatability below 4%. For reproducibility, the CV of most of the indices were below 6%. The deformation amplitude (DA ratio in 1 mm and integrated radius were below 4% (1.2% and 3.8%, resp.. Conclusions. The Corvis ST showed good precision (repeatability and reproducibility for IOP measurements and for DCR in healthy eyes.

  17. Assessment of intraocular pressure sensing using an implanted reflective flexible membrane

    Science.gov (United States)

    Nazarov, Andrey; Knyazer, Boris; Lifshitz, Tova; Schvartzman, Mark; Abdulhalim, Ibrahim

    2017-04-01

    Glaucoma is a neurodegenerative condition that is the leading cause of irreversible blindness worldwide. Elevated intraocular pressure (IOP) is the main cause for the development of the disease. The symptoms of this form, such as deterioration of vision and scotomas (loss of visual fields), appear in the latter stages of the disease. Therefore, an IOP monitoring device is needed for better, simpler, and faster diagnosis, and to enable a fast treatment response. We present a theoretical assessment as well as preliminary experimental results of a simple approach for easy, optical, IOP self-monitoring. It is based on a polydimethylsiloxane membrane coated with a reflective layer and a Hartmann-Shack wavefront sensor. Nearly linear correlation is found between membrane deformation and Zernike coefficients representing defocus primary spherical aberration, with high sensitivity and negligible dependence on the measurement distance. The proposed device is expected to provide an accurate IOP measurement resolution of less than ±0.2 mm Hg with a pressure dependence on working distances IOP values-up to 40 mm Hg.

  18. Evaluation of the ICare rebound tonometer as a home intraocular pressure monitoring device.

    Science.gov (United States)

    Asrani, Sanjay; Chatterjee, Ashmita; Wallace, David K; Santiago-Turla, Cecilia; Stinnett, Sandra

    2011-02-01

    (a) To investigate whether the ICare rebound tonometer can provide accurate measurements of intraocular pressure (IOP) in the hands of an inexperienced user compared with ICare measurements and Goldmann tonometry by a trained technician and (b) to assess the intrauser reproducibility of IOP measurements and the learning curve among patients using the ICare rebound tonometer. A trained technician used the ICare rebound tonometer to measure the IOP of the right eye of 100 glaucoma patients. The technician then instructed each patient on use of the ICare tonometer. Each patient then measured his/her own pressure using the ICare tonometer. Finally, a different technician, who was masked to both of the earlier readings, measured IOP by Goldmann applanation tonometry. Thirty patients repeated the ICare measurement 3 times (once every 5 min) 20 minutes after the initial IOP measurement. Of the 100 patients, 82 of patient ICare and the technician ICare readings were within 3 mm Hg of each other, and 75 of the patient ICare and Goldmann applanation tonometry measurements were within 3 mm Hg of each other. Intraclass correlations between self-administered ICare measurements 1 and 2, 1 and 3, and 2 and 3 were 0.69, 0.71 and 0.81, respectively. In this study, the ICare rebound tonometer was accurate and reliable in the hands of patients. Patients can easily learn to self-administer this test, possibly allowing for home monitoring of IOP.

  19. Elevation of Intraocular Pressure After Intravitreal Injection of Triamcinolone Acetonide in Taiwanese Patients

    Directory of Open Access Journals (Sweden)

    Yo-Chen Chang

    2008-02-01

    Full Text Available The purpose of this study was to investigate the incidence and timing of elevation in intraocular pressure (IOP after intravitreal injection of triamcinolone acetonide (IVTA. This was a retrospective observational case series that included 52 eyes from 52 patients. All patients received intravitreal injection with 4 mg of triamcinolone acetonide. Significant IOP elevation was defined as pressure greater than 21 mmHg. There were 26 males and 26 females included in this study. The mean age was 59.4 years. The mean IOP at baseline and postoperative mean highest IOP were 14.6 mmHg and 21.5 mmHg, respectively. There were 19 (36.5% patients who experienced significant IOP elevation at a mean of 26.0 days after IVTA. IOP was well-controlled by topical antiglaucoma medication in 17 of these 19 patients. IOP elevation after intravitreal injection with 4 mg of triamcinolone acetonide is not a rare finding. This phenomenon usually starts approximately 1 month after IVTA. Patients considering this treatment should be fully informed of this known adverse effect.

  20. Meta-analysis of 24-hour intraocular pressure studies evaluating the efficacy of glaucoma medicines.

    Science.gov (United States)

    Stewart, William C; Konstas, Anastasios G P; Nelson, Lindsay A; Kruft, Bonnie

    2008-07-01

    To evaluate efficacy and safety data of currently available ocular hypotensive medicines derived from 24-hour studies, of similar design, in patients with primary open-angle glaucoma (POAG), exfoliative glaucoma, or ocular hypertension (OH). Meta-analysis of published articles evaluating patients with POAG, exfoliative glaucoma, or OH. We included articles that were randomized, prospective, single- or double-masked, comparative studies of ocular hypotensive therapies over 24 hours. Each article selected contained an untreated baseline, >or=4-week treatment period, >/=20 patients per treatment arm, and >or=6 time points not spaced >5 hours apart and used Goldmann applanation or Tonopen tonometry (supine measurements) to measure intraocular pressure (IOP). Twenty-four-hour IOP efficacy. This analysis included 864 separate 24-hour treatment curves from 386 patients in 28 treatment arms from 11 studies. A statistical difference in the mean diurnal pressure decrease existed between monotherapy treatments for POAG/OH patients, with bimatoprost (29%) and travoprost (27%) showing the greatest 24-hour reduction (P = 0.026). Timolol 0.5% was less effective than latanoprost (24% vs. 19% reduction) but decreased the pressure at each night time point (P = 0.0003). Dorzolamide showed a 19% 24-hour pressure reduction and brimonidine 0.2% a 14% one. In exfoliative glaucoma patients, latanoprost and travoprost showed higher baseline and treatment pressures, although the pressure reductions (29% and 31%, respectively) were greater generally than observed with POAG/OH. An evening-dosed latanoprost/timolol fixed combination reduced the pressure 33%, and the dorzolamide/timolol fixed combination (DTFC), 26%. However, the power to detect a difference for this specific comparison was probably low, due to the limited number of patients (n = 20) in the DTFC group. A statistical difference between evening-dosed (24%) and morning-dosed (18%) latanoprost (Pmorning (26%) travoprost (P = 0

  1. Central corneal thickness and intraocular pressure in the Cameroonian nonglaucomatous population

    Directory of Open Access Journals (Sweden)

    André Omgbwa Eballe

    2010-07-01

    Full Text Available André Omgbwa Eballe1, Godefroy Koki2, Augustin Ellong2, Didier Owono2, Emilienne Epée2, Lucienne Assumpta Bella2, Côme Ebana Mvogo1, Jeanne Mayouego Kouam21Faculty of Medicine and Pharmaceuticals Sciences, University of Douala; 2Faculty of Medicine and Biomedical Sciences, University of Yaoundé, CameroonAim: We performed a prospective, analytical study from 01 January to 31 March 2009 in the Ophthalmology Unit of the Gyneco-Obstetric and Pediatric Hospital of Yaounde, aiming to determine the profile of central corneal thickness (CCT in the Cameroonian nonglaucomatous black population and its relationship with intraocular pressure (IOP.Results and discussion: Four hundred and eighty-five patients (970 eyes meeting our ­inclusion criteria were selected for this study. The average CCT was 529.29 ± 35.9 µm in the right eye (95% confidence interval [CI]: 526.09–532.49, 528.19 ± 35.9 µm in the left eye (95% CI: 524.99–531.40 and 528.74 ± 35.89 µm in both eyes (95% CI: 526.48–531.00, range 440 to 670 µm. The average IOP was 13.01 ± 2.97 mmHg in both eyes (95% CI: 12.82–13.19. A rise in CCT by 100 µm was followed by an increase in IOP of about 2.8 mmHg (95% CI: 2.3–3.6 for both eyes taken together. Linear regression analysis showed that corneal thickness was negatively correlated with age and IOP was positively related with age.Conclusion: CCT in the Cameroonian nonglaucomatous black population was found to be lower compared with CCT values in Caucasian and Asian populations. On the basis of reference values ranging between 527 and 560 µm, an adjustment of IOP values by a correction factor is required for many Cameroonian patients. This will improve the diagnosis and follow-up of glaucoma by helping to detect true ocular hypertension.Keywords: central corneal thickness, intraocular pressure, Cameroon

  2. Clinical factors affecting intraocular pressure change after orbital decompression surgery in thyroid-associated ophthalmopathy

    Directory of Open Access Journals (Sweden)

    Jeong JH

    2016-01-01

    Full Text Available Jae Hoon Jeong,1 Jeong Kyu Lee,1,2 Dong Ik Lee,1 Yeoun Sook Chun,1 Bo Youn Cho2 1Department of Ophthalmology, College of Medicine, Chung-Ang University 2Thyroid Center, Chung-Ang University Hospital, Seoul, Korea Objective: To report the physiological monitoring of intraocular pressure (IOP during the postoperative periods after orbital decompression surgery and ascertain the correlation between the clinical factors and IOP changes.Methods: The medical records of 113 orbits from 60 patients who underwent orbital decompression surgery were reviewed retrospectively. IOP measurement during the postoperative periods was classified based on the postoperative day: week 1 (1–7 days, month 1 (8–41 days, month 2 (42–70 days, month 3 (71–97 days, month 4 (98–126 days, and final (after 127 days. The mean postoperative follow-up was 286.5 days for orbits with at least 6 months of follow-up. Univariate and multivariate linear regression analyses were performed to assess the correlation between the IOP reduction percentage and clinical factors.Results: The mean IOP increased from 16.9 to 18.6 mmHg (10.1% at postoperative week 1 and decreased to 14.4 mmHg (14.5% after 2 months. Minimal little changes were observed postoperatively in the IOP after 2 months. Preoperative IOP had a significant positive effect on the reduction percentage both at postoperative week 1 (β=2.51, P=0.001 and after 2 months (β=1.07, P=0.029, and the spherical equivalent showed a positive correlation with the reduction level at postoperative week 1 (β=1.71, P=0.021.Conclusion: Surgical decompression caused a significant reduction in the IOP in thyroid-associated orbitopathy, and the amount of reduction was closely related to preoperative IOP; however, it may also cause a transient elevation in the IOP during the early postoperative phase in highly myopic eyes. Keywords: Graves’ ophthalmopathy, intraocular pressure, myopia, physiologic monitoring, postoperative periods

  3. Insertion of laryngeal mask airway does not increase the intraocular pressure in children with glaucoma.

    Science.gov (United States)

    Bhardwaj, Neerja; Yaddanapudi, Sandhya; Singh, Swati; Pandav, Surinder S

    2011-10-01

    It is hypothesized that in children with glaucoma, the insertion of laryngeal mask airway (LMA) will cause lesser rise in intraocular pressure (IOP) than tracheal tube (TT). To compare the IOP response to LMA and TT insertion in children with glaucoma. A prospective, randomized, single-blind study was conducted in 30 glaucomatous ASA-1 children, aged 1-10 years scheduled to undergo trabeculectomy. Anesthesia was induced with halothane and maintained for 5 min with 1 MAC of halothane after administering atracurium 0.5 mg·kg(-1) following which LMA or TT was introduced. IOP was measured in both the eyes before and after insertion of airway device for 5 min. The IOP increased significantly from 27.3 ± 5.2 to 31.2 ± 5.4 mmHg (P insertion of LMA. The IOP was significantly higher in group TT compared to group LMA at 2 min (P = 0.004) and 5 min (P = 0.01) after the device insertion. The heart rate (HR) increased significantly after tracheal intubation and returned to baseline 4 min after intubation. The HR increase was significantly more in TT group compared to LMA group at all times of observation. Both systolic blood pressure (SBP; P = 0.01) and diastolic blood pressure (DBP; P = 0.02) showed an increase at 1 min in children in group TT. Insertion of LMA in glaucomatous children is not associated with an increased IOP response or cardiovascular changes. © 2011 Blackwell Publishing Ltd.

  4. Age-related changes in biomechanical parameters of the cornea and intraocular pressure in a healthy Turkish population

    OpenAIRE

    ŞEN, Emine; ELGİN, Kadriye Ufuk; YÜKSEKKAYA, Pınar; TIRHIŞ, Mehmet Hakan

    2014-01-01

    To investigate age-related changes in intraocular pressure (IOP) and biomechanical parameters of the cornea in healthy subjects. Materials and methods: There were 404 healthy subjects included prospectively in this study. The subjects were divided into 3 groups (Group 1: 93 subjects aged 60). Corneal compensated IOP (IOPcc), Goldmann correlated IOP (IOPg), corneal hysteresis (CH), and corneal resistance factor (CRF) were measured by the Ocular Response Analyzer. Results: When all the study...

  5. Twenty-Four-Hour Intraocular Pressure Related Changes Following Adjuvant Selective Laser Trabeculoplasty for Normal Tension Glaucoma

    OpenAIRE

    Lee, Jacky W. Y.; Fu, Lin; Chan, Jonathan C.H.; Lai, Jimmy S. M.

    2014-01-01

    Abstract To investigate intraocular pressure (IOP) related patterns before and after selective laser trabeculoplasty (SLT) for normal tension glaucoma (NTG). In this prospective cohort study, 18 NTG patients underwent SLT. Success was defined as IOP reduction ≥20% by Goldmann applanation tonometry. 24-hour IOP-related pattern recording with a contact lens sensor (CLS) (SENSIMED Triggerfish®, Sensimed, Switzerland) was done before (baseline) and 1 month after SLT. A cosine function was fitted ...

  6. The Heritability of Glaucoma-Related Traits Corneal Hysteresis, Central Corneal Thickness, Intraocular Pressure, and Choroidal Blood Flow Pulsatility

    OpenAIRE

    Ellen E Freeman; Marie-Hélène Roy-Gagnon; Denise Descovich; Hugues Massé; Lesk, Mark R.

    2013-01-01

    PURPOSE: The purpose of this work was to investigate the heritability of potential glaucoma endophenotypes. We estimated for the first time the heritability of the pulsatility of choroidal blood flow. We also sought to confirm the heritability of corneal hysteresis, central corneal thickness, and 3 ways of measuring intraocular pressure. METHODS: Measurements were performed on 96 first-degree relatives recruited from Maisonneuve-Rosemont Hospital in Montreal. Corneal hysteresis was determined...

  7. Therapeutic ultrasound for glaucoma: clinical use of a low-frequency low-power ultrasound device for lowering intraocular pressure.

    Science.gov (United States)

    Schwartz, Donald; Samples, John; Korosteleva, Olga

    2014-01-01

    This is a first-in-human study to determine the efficacy and tolerability of a new method of treating glaucoma using a low-power, low-frequency, focused therapeutic ultrasound for glaucoma (TUG) device designed to trigger an inflammatory reaction in the anterior chamber angle and trabecular meshwork to enhance outflow. The use of the device is anticipated for mild or moderate open-angle glaucoma as an enhancement to outflow. In a two-branch clinical trial, a total of 26 primary open-angle glaucoma patients underwent a procedure consisting of the external application of the TUG device. In branch 1, nine of these patients were naïve to pharmaceutical treatment or had been off of medication for over 6 months. In branch 2, 17 patients were treated after a medication washout period. All patients in the study were followed for 12 months. In branch 1, there was a decrease in intraocular pressure averaging over 20% lasting at least a year in 74% of the eyes with non-normotensive open-angle glaucoma. In branch 2, an average of two visits while on medication provided the comparison intraocular pressure (IOP) to the effect of the TUG treatment after washout. It was seen that the intraocular pressure over the year post-treatment was equal to or better than the pharmaceutical control in close to 80% of measurements. A novel device for lowering intraocular pressure is described with a potential for adding to our armamentarium for treating glaucoma. This is a small cohort study which indicates beneficial trends. The study was a registered clinical trial, #ISRCTN50904302.

  8. Biomechanical properties of crystalline lens as a function of intraocular pressure assessed noninvasively by optical coherence elastography

    Science.gov (United States)

    Wu, Chen; Aglyamov, Salavat R.; Liu, Chih-Hao; Han, Zhaolong; Singh, Manmohan; Larin, Kirill V.

    2017-02-01

    Many ocular diseases such as glaucoma and uveitis can lead to the elevation of intraocular pressure (IOP). Previous research implies a link between elevated IOP and lens disease. However, the relationship between IOP elevation and biomechanical properties of the crystalline lens has not been directly studied yet. In this work, we investigated the biomechanical properties of porcine lens as a function of IOP by acoustic radiation force optical coherence elastography.

  9. Screening of intraocular pressure before routine pupil dilation for retinal photography: Clinical case report

    Directory of Open Access Journals (Sweden)

    Lap-kin Chiang

    2016-12-01

    Full Text Available Introduction: Pharmacologic dilation of the pupil results in twice the sensitivity of detection of diabetic retinopathy compared with undilated retinal examination. The potential risk of acute angle-closure glaucoma after pupil dilation has been hypothesized to be higher in Asian patients with diabetes mellitus. Clinical case: A 61-year-old man with diabetes mellitus and hypertension was incidentally found to have elevated intraocular pressure (IOP before routine retinal photography. He was asymptomatic and the visual acuity was 0.67 for both eyes. An ophthalmologist later found he had anatomical narrow-angle borderline glaucoma. Topical administration of pilocarpine and oral administration of acetazolamide were initiated, and laser iridotomy was later performed. IOP screening: Among 1736 diabetic and/or hypertensive patients who underwent IOP screening, 31 patients (1.8% had IOP of any eye persistently higher than 21 mm Hg on at least two occasions. The mean (standard deviation IOP of the right eye was 24.1 (2.1 mm Hg, while that of the left eye was 24.6 (2.5 mm Hg. Four patients (12.9% were found to have glaucoma, and treatment was initiated by an ophthalmologist. Therefore further study should be conducted to evaluate the cost-effectiveness of IOP screening among this group of patients.

  10. Intraocular pressure changes: an important determinant of the biocompatibility of intravitreous implants.

    Directory of Open Access Journals (Sweden)

    Ling Zou

    Full Text Available In recent years, research efforts exploring the possibility of using biomaterial nanoparticles for intravitreous drug delivery has increased significantly. However, little is known about the effect of material properties on intravitreous tissue responses.To find the answer, nanoparticles made of hyaluronic acid (HA, poly (l-lactic acid (PLLA, polystyrene (PS, and Poly N-isopropyl acrylamide (PNIPAM were tested using intravitreous rabbit implantation model. Shortly after implantation, we found that most of the implants accumulated in the trabecular meshwork area followed by clearance from the vitreous. Interestingly, substantial reduction of intraocular pressure (IOP was observed in eyes implanted with particles made of PS, PNIPAM and PLLA, but not HA nanoparticles and buffered salt solution control. On the other hand, based on histology, we found that the particle implantation had no influence on cornea, iris and even retina. Surprisingly, substantial CD11b+ inflammatory cells were found to accumulate in the trabecular meshwork area in some animals. In addition, there was a good relationship between recruited CD11b+ cells and IOP reduction.Overall, the results reveal the potential influence of nanoparticle material properties on IOP reduction and inflammatory responses in trabecular meshwork. Such interactions may be critical for the development of future ocular nanodevices with improved safety and perhaps efficacy.

  11. The measurement of intraocular pressure over positive soft contact lenses by rebound tonometry.

    Science.gov (United States)

    Zeri, Fabrizio; De Cusatis, Mario; Lupelli, Luigi; Swann, Peter Graham

    2016-01-01

    To investigate if the accuracy of intraocular pressure (IOP) measurements using rebound tonometry over disposable hydrogel (etafilcon A) contact lenses (CL) is affected by the positive power of the CLs. The experimental group comprised 26 subjects, (8 male, 18 female). IOP measurements were undertaken on the subjects' right eyes in random order using a Rebound Tonometer (ICare). The CLs had powers of +2.00D and +6.00D. Measurements were taken over each contact lens and also before and after the CLs had been worn. The IOP measure obtained with both CLs was significantly lower compared to the value without CLs (t test; p<0.001) but no significant difference was found between the two powers of CLs. Rebound tonometry over positive hydrogel CLs leads to a certain degree of IOP underestimation. This result did not change for the two positive lenses used in the experiment, despite their large difference in power and therefore in lens thickness. Optometrists should bear this in mind when measuring IOP with the rebound tonometer over plus power contact lenses. Copyright © 2016 The Authors. Published by Elsevier Espana.. All rights reserved.

  12. Intraocular pressure and influencing systemic health parameters in a Korean population

    Directory of Open Access Journals (Sweden)

    Young Sang Han

    2014-01-01

    Full Text Available Aim: To evaluate the relationship between intraocular pressure (IOP and systemic health parameters such as age, gender, body mass index (BMI, total cholesterol, high density lipoprotein (HDL, and triglyceride (TG in a Korean population. Materials and Methods: A total of 30,893 healthy subjects underwent automated multiphasic tests, including non-contact tonometry, automated perimetry, fundus photography, and blood samplings for total cholesterol, HDL, and TG. Seven age groups were divided by decades ranging from 20 to 29 years to 80 + years. The association between IOP and BMI, plasma lipid profiles was examined using cross-sectional analysis. Results: The mean age of subjects was 47.7 years. The mean IOP of subjects was 15.4 ± 3.2 mmHg for both eyes. The mean IOP of men was significantly higher than women ( P = 0.000. By multiple linear regression analysis, IOP was positively associated with gender (male, BMI, total cholesterol, and TG and negatively associated with age ( P = 0.000. BMI, total cholesterol, and TG had significantly positive correlations with IOP after adjusting for age, gender, and other variables which can influence the IOP ( P = 0.000. Conclusions: In a Korean population, the mean IOP, total cholesterol, TG, and BMI values of men were higher than women. IOP was found to increase with total cholesterol, TG, BMI, and to decrease with only age regardless of sex.

  13. The Effect of Dehydration and Fasting on Corneal Biomechanical Properties and Intraocular Pressure.

    Science.gov (United States)

    Oltulu, Refik; Satirtav, Gunhal; Ersan, Ismail; Soylu, Erkan; Okka, Mehmet; Zengin, Nazmi

    2016-11-01

    To evaluate the changes in corneal biomechanical properties and intraocular pressure (IOP) during fasting period in healthy subjects. Seventy-two eyes of 72 fasting subjects (study group), and 62 eyes of 62 nonfasting subjects (control group) were enrolled in this prospective study undertaken at a single university hospital. All subjects underwent complete ophthalmologic examination including ocular biomechanical evaluation with ocular response analyzer. Ocular response analyzer measurement was performed on the right eyes of the subjects between 5.00 and 6.00 PM after approximately 14 hr of fasting for the study group and after a nonfasting period for the control group. The corneal hysteresis, corneal resistance factor, mean corneal compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) values were measured with a patented dynamic bidirectional applanation process. Goldmann-correlated IOP and IOPcc measurements in the study group and the control group were found as 13.8±2.8 mm Hg, 14.6±2.6 mm Hg and 16.3±2.2 mm Hg, 15.7±2.4 mm Hg, respectively. There was statistically significant difference within the two groups in IOPg and IOPcc (Pcorneal hysteresis and corneal resistance factor significantly decreased in study group compared with control group (Pcorneal hysteresis, and corneal resistance factor in healthy subjects, altering the biomechanical properties of the cornea.

  14. Effects of eye rubbing and breath holding on corneal biomechanical properties and intraocular pressure.

    Science.gov (United States)

    Liu, Wan-Cherng; Lee, Shui-Mei; Graham, Andrew D; Lin, Meng C

    2011-08-01

    To determine whether corneal biomechanical properties and intraocular pressure (IOP) are affected by eye rubbing and breath holding. Corneal hysteresis, corneal resistance factor, corneal compensated IOP (IOPcc), and Goldmann equivalent IOP (IOPg) were measured on both eyes of 40 subjects. Measurements were taken at baseline before eye rubbing (ER(0)) and before breath holding (BH(0)), immediately after 2 episodes of eye rubbing (ER(1) and ER(2)), and during 2 episodes of breath holding (BH(1) and BH(2)). Corneal hysteresis, corneal resistance factor, and IOPg were significantly lower after ER(1) compared with ER(0) and were significantly lower after ER(2) compared with ER(1). In contrast, IOPcc did not decrease significantly. There were no significant differences among BH(0), BH(1), and BH(2) in any of the 4 outcomes. Eye rubbing should be avoided before measurements of corneal biomechanical properties and IOPg. In contrast, breath holding during measurements is not likely to cause a significant change in IOPg and IOPcc or corneal biomechanical properties.

  15. The relationship between corneal hysteresis and the magnitude of intraocular pressure reduction with topical prostaglandin therapy.

    Science.gov (United States)

    Agarwal, Daniel R; Ehrlich, Joshua R; Shimmyo, Mitsugu; Radcliffe, Nathan M

    2012-02-01

    To evaluate corneal hysteresis (CH) and intraocular pressure (IOP) before and after IOP lowering with prostaglandin analogue (PGA) therapy in medication-naïve eyes. In this retrospective study, we included records from 57 consecutive patients with open angle glaucoma who were initiated on PGA. Patients underwent ocular response analyser measurement with IOP assessment at baseline (untreated) and at follow-up (treated). Median follow-up time between IOP measurements was 1.4 (range 0.4-13.5) months. IOP was reduced by 3.2 mm Hg (18.8%) from 17.0 to 13.8 mm Hg (pcorneal thickness) was a significant predictor of the magnitude of IOP reduction, with patients in the lowest quartile of CH (mean 7.0 mm Hg) experiencing a 29.0% reduction in IOP while those in the highest CH quartile (mean 11.9 mm Hg) experienced a 7.6% reduction in IOP (p=0.006). A multivariate analysis controlling for baseline IOP demonstrated that baseline CH independently predicted the magnitude of IOP reduction with PGA therapy in both per cent (ß=3.5, p=0.01) and absolute (ß=0.6, p=0.02) terms. Although CH is influenced by IOP, baseline CH is independently associated with the magnitude of IOP reduction with PGA therapy.

  16. Optic disc planimetry, corneal hysteresis, central corneal thickness, and intraocular pressure as risk factors for glaucoma.

    Science.gov (United States)

    Carbonaro, Francis; Hysi, Pirro G; Fahy, Samantha J; Nag, Abhishek; Hammond, Christopher J

    2014-02-01

    To determine whether corneal hysteresis and central corneal thickness are independent risk factors for glaucoma. A cross-sectional population-based cohort study. Associations were tested between corneal hysteresis, measured in 1754 population-based subjects from the TwinsUK cohort, and glaucoma-related endophenotypes, including intraocular pressure (IOP), vertical cup-to-disc ratio, optic disc area, and optic disc cup area. Corneal hysteresis, IOP, and central corneal thickness (CCT) were measured; optic disc photographs were analyzed; and multivariable linear regression analysis was performed. Data were available on 1645 individuals. Multiple regression analysis showed corneal hysteresis to be significantly negatively associated with age (beta coefficient = -0.03, P Corneal hysteresis was also found to be associated with CCT (beta coefficient = 0.02, P corneal hysteresis and optic disc area (P = .6), cup area (P = .77), vertical cup-to-disc ratio (P = .51), or spherical equivalent (P = .08). CCT was also found to be significantly associated with IOP (beta coefficient = 3.3, P corneal hysteresis (beta coefficient = 9.4, P corneal hysteresis or CCT and quantitative measures of optic disc cupping, suggesting that corneal hysteresis and CCT are not independent risk factors for glaucoma. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. [The influence of corneal hysteresis and corneal resistance factor on the measurement of intraocular pressure].

    Science.gov (United States)

    Hager, A; Schroeder, B; Sadeghi, M; Grossherr, M; Wiegand, W

    2007-06-01

    The influence of central corneal thickness (CCT) on the measurement of intraocular pressure (IOP) has been discussed extensively in recent years. The problem, however, has not been solved so far. In addition to CCT there are probably further biomechanical properties that play a role in IOP measurement. We wanted to find out whether these properties are related to Goldmann applanation tonometry (GAT), noncontact tonometry (NCT), or CCT. Biomechanical properties of the cornea such as corneal hysteresis (CH) and corneal resistance factor (CRF) can be measured with the Ocular Response Analyzer (ORA, Reichert Ophthalmic Instruments, Depew, NY, USA). Furthermore, a corneal compensated IOP (IOPcc) is given. We examined 156 normal eyes of 80 patients who did not show corneal pathology nor glaucoma. In each eye GAT, NCT, and ORA data as well as CCT were measured. Data were statistically analyzed with respect to agreement and the influence of CH and CRF on IOP measurement. In our patients the following average values were calculated: GAT 14.8+/-3.0 mmHg, NCT 16.4+/-3.9 mmHg, IOPcc 16.2+/-4.1 mmHg, CH 10.6+/-2.3 mmHg, CRF 10.9+/-2.4 mmHg, and CCT 557+/-36 microm. IOPcc was not related to CCT in normal eyes and the only IOP value related to CH (pcorneal thickness. Corneal hysteresis and corneal resistance factor provide further information about biomechanical properties of the cornea beyond central corneal thickness.

  18. Comparison of different intraocular pressure measurement techniques in normal eyes and post small incision lenticule extraction

    Directory of Open Access Journals (Sweden)

    Hosny M

    2017-07-01

    Full Text Available Mohamed Hosny, Fayrouz Aboalazayem, Hoda El Shiwy, Mohsen Salem Department of Ophthalmology, Cairo University, Giza, Egypt Purpose: The purpose of the study was to determine the accuracy of intraocular pressure (IOP measurement after small incision lenticule extraction (SMILE using Goldmann applanation tonometry (GAT and ocular response analyzer (ORA.Methods: This is a prospective clinical study that was conducted on 30 eyes in the interval between February 2016 and September 2016. The age of the patients ranged between 19 and 40 years. The patients underwent SMILE surgery using the femto laser. IOP was measured preoperatively and 1 month postoperatively by both techniques, the GAT and the ORA.Results: GAT recorded lower values than ORA values (IOPcc preoperatively and postoperatively and the difference was statistically significant. Both GAT and ORA IOP measurements decreased after SMILE. There was no statistically significant correlation between the changes in the GAT and ORA readings and the postoperative corneal pachymetry or the lenticule thickness. Both corneal hysteresis and corneal resistance factor showed significant decline after the procedure, which correlated with the lenticule thickness.Conclusion: SMILE causes significant reduction in IOP measurement by ORA and GAT. Corneal biomechanics decreases following SMILE and this correlates with lenticule thickness. Keywords: ocular response analyzer, small incision lenticule extraction, corneal hysteresis

  19. Corneal hysteresis with intraocular pressure of a wide range: a test on porcine eyes.

    Science.gov (United States)

    Tao, Chen; Han, Zhaolong; Sun, Yong; Zhou, Chuanqing; Roberts, Cynthia; Zhou, Dai; Ren, Qiushi

    2013-12-01

    To investigate the relationship between corneal hysteresis (CH) and intraocular pressure (IOP) using porcine eyes in the low to high IOP ranges. In vitro porcine eyes were used to investigate the relationship of CH and IOP. IOP was altered by changing the height of a drip stand within the dynamic range of 60 mm Hg. CH and IOP were measured with the Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments, Depew, NY) at different heights. Second-order polynomial regression method was employed to assess the nonlinear correlation of CH and IOP. CH demonstrated an initial plateau stage with low IOP, which then decreased as IOP increased to higher values up to 60 mm Hg. The maximum CH value of approximately 6 to 8 mm Hg was achieved when IOP ranged from 11 to 25 mm Hg. The nonlinear regression lines of Goldmann correlated IOP (IOPg) and CH can be described as CH = − 0.0029 × IOPg2 + 0.1005 × IOPg + 5.2824, R2 = 0.3676, P < .05. CH was relatively constant for lower values of IOP and showed a decreasing relationship at higher values of IOP. This nonlinear relationship provides insight into understanding the viscoelastic nature of CH over a wider range of IOP values. The experimental data on porcine eyes may indicate that IOP should be taken into account when analyzing the deformation response of the cornea to an applied air puff.

  20. Schiotz tonometry accurately measures intraocular pressure in Boston type 1 keratoprosthesis eyes.

    Science.gov (United States)

    Estrovich, Igor E; Shen, Chris; Chu, Yvonne; Downs, J Crawford; Gardiner, Stuart; Straiko, Michael; Mansberger, Steven L

    2015-06-01

    To evaluate the location of the eye and tonometry device that provides the most accurate intraocular pressure (IOP) measurements in eyes with Boston type 1 keratoprosthesis. A single surgeon sutured a Boston keratoprosthesis into the central cornea in the usual manner in 5 eyes of deceased donors. Another investigator used a 27-gauge needle, digital manometry, and gravity infusion to set the IOP at levels of 10, 20, 30, and 40 mm Hg in random order. A second investigator masked to the level of IOP used a Schiotz tonometer (Sklar) with a 7.5-g plunger load and a Tono-pen XL tonometer (Medtronic) to determine IOP at the temporal corneoscleral limbus and temporal sclera (3 mm temporal to the corneoscleral limbus). We used generalized estimation equation models to determine an average absolute difference between the tonometer measurements compared with the "gold standard" digital manometric IOP. The Schiotz tonometer had a lower median absolute error compared with the Tono-pen at both temporal sclera (5.4 mm Hg vs. 39.0 mm Hg, P keratoprosthesis.

  1. Short-term enhancement of visual field sensitivity in glaucomatous eyes following surgical intraocular pressure reduction.

    Science.gov (United States)

    Wright, Tracy M; Goharian, Iman; Gardiner, Stuart K; Sehi, Mitra; Greenfield, David S

    2015-02-01

    To examine the hypothesis that surgical intraocular pressure (IOP) reduction leads to enhancement of visual field (VF) sensitivity in glaucomatous eyes. Prospective case-control study. Patients with uncontrolled IOP requiring trabeculectomy or aqueous drainage device were enrolled. Controls consisted of medically treated glaucoma patients with stable IOP and no change in medical therapy during follow-up. Two baseline preoperative VFs and 3 follow-up VF examinations at 1, 2, and 3 months postoperatively were used for analysis. The same number of VF examinations measured within an 18-month interval was used for control eyes. VF locations with significant change were defined as exceeding 95% test-retest confidence limits based upon the mean sensitivity using the 2 baseline VF exams. The number of significantly changing locations per eye and changes in mean and pattern standard deviation (PSD) from the mean baseline fields were compared between groups using a Poisson generalized estimating equation model. Thirty eyes of 30 surgically treated glaucoma patients and 41 eyes of 28 stable controls were enrolled. Postoperative IOP was decreased at follow-up 3 compared with baseline (P IOP in glaucomatous eyes and may represent a potential biomarker for retinal ganglion cell response to therapeutic interventions in glaucoma. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. [Mobile intraocular pressure measurement. From palpation to initial clinical experience with the handheld dynamic contour tonometer].

    Science.gov (United States)

    Schmid, U; Kniestedt, C

    2010-07-01

    Goldmann applanation tonometry is still the gold standard of intraocular pressure measurement (IOP) and an essential part in the diagnosis of glaucoma. Applanation tonometry is usually performed on a sitting patient at the slit lamp. However, under certain circumstances it is necessary to measure the IOP outside the office setting. With handheld devices the measuring procedure is brought to bedside and surgery theatres, as well as to patients who are not able to sit behind the slit lamp. The dynamic contour tonometer (DCT) represents a new method of direct IOP measurement. Its physical principle is based on piezo-electronic contour matching tonometry and is claimed to be less dependent on biochemical properties of the cornea. Besides the IOP, the ocular pulse amplitude can also be measured. Until now, the DCT had been available as a slit lamp mounted device. In this report, we present a portable prototype of the device. In comparison with the Perkins tonometer and the TONO-PEN XL, the handheld DCT shows smaller intra- and inter-examiner variability. Additionally, the device offers the unique possibility to display the ocular pulse amplitude while the patient is in a horizontal position.

  3. INTRAOCULAR PRESSURE IN SOUTHERN ROCKHOPPER (EUDYPTES CHRYSOCOME) AND MACARONI PENGUINS (EUDYPTES CHRYSOLOPHUS): EVALUATION OF INFLUENCING FACTORS.

    Science.gov (United States)

    Woodhouse, Sarah J; Peterson, Edward L; Schmitt, Todd; Aquino, Susette

    2016-03-01

    Ophthalmic examinations were performed on 160 macaroni penguins (Eudyptes chrysolophus) and 90 southern rockhopper penguins (Eudyptes chrysocome) at eight North American zoos and aquaria. Intraocular pressure (IOP) was measured using rebound tonometry while penguins were held in two different body positions. Correlations between IOP and factors including age, body position, eye pathology, and housing parameters were evaluated. Normal macaroni penguins had a mean IOP of 42.0 ± 9.7 mm Hg. Normal rockhopper penguins had a mean IOP of 32.9 ± 6.2 mm Hg. Neither species had significantly different IOP between sexes or between left and right eyes of the same penguin. In both species, there was a negative linear correlation between age and IOP. In the macaroni population, IOP was significantly higher when IOP measurement was performed before ophthalmic exam; this was not true in rockhoppers. In both species, IOP measured in a horizontal body position was significantly higher than IOP measured in a vertical body position. In both species, eyes with corneal lesions had significantly lower IOP than normal eyes. In the macaroni penguin, eyes with rubeosis iridis had significantly lower IOP than normal eyes. In macaroni penguins, eyes with cataracts had significantly lower mean IOP than normal eyes; this was not true for rockhoppers.

  4. Upcoming methods and specifications of continuous intraocular pressure monitoring systems for glaucoma

    Directory of Open Access Journals (Sweden)

    Amir Molaei

    2018-01-01

    Full Text Available Glaucoma is the leading cause of irreversible blindness and vision loss in the world. Although intraocular pressure (IOP is no longer considered the only risk factor for glaucoma, it is still the most important one. In most cases, high IOP is secondary to trabecular meshwork dysfunction. High IOP leads to compaction of the lamina cribrosa and subsequent damage to retinal ganglion cell axons. Damage to the optic nerve head is evident on funduscopy as posterior bowing of the lamina cribrosa and increased cupping. Currently, the only documented method to slow or halt the progression of this disease is to decrease the IOP; hence, accurate IOP measurement is crucial not only for diagnosis, but also for the management. Due to the dynamic nature and fluctuation of the IOP, a single clinical measurement is not a reliable indicator of diurnal IOP; it requires 24-hour monitoring methods. Technological advances in microelectromechanical systems and microfluidics provide a promising solution for the effective measurement of IOP. This paper provides a broad overview of the upcoming technologies to be used for continuous IOP monitoring.

  5. Intraocular Pressure Changes: An Important Determinant of the Biocompatibility of Intravitreous Implants

    Science.gov (United States)

    Zou, Ling; Nair, Ashwin; Weng, Hong; Tsai, Yi-Ting; Hu, Zhibing; Tang, Liping

    2011-01-01

    Background In recent years, research efforts exploring the possibility of using biomaterial nanoparticles for intravitreous drug delivery has increased significantly. However, little is known about the effect of material properties on intravitreous tissue responses. Principal Findings To find the answer, nanoparticles made of hyaluronic acid (HA), poly (l-lactic acid) (PLLA), polystyrene (PS), and Poly N-isopropyl acrylamide (PNIPAM) were tested using intravitreous rabbit implantation model. Shortly after implantation, we found that most of the implants accumulated in the trabecular meshwork area followed by clearance from the vitreous. Interestingly, substantial reduction of intraocular pressure (IOP) was observed in eyes implanted with particles made of PS, PNIPAM and PLLA, but not HA nanoparticles and buffered salt solution control. On the other hand, based on histology, we found that the particle implantation had no influence on cornea, iris and even retina. Surprisingly, substantial CD11b+ inflammatory cells were found to accumulate in the trabecular meshwork area in some animals. In addition, there was a good relationship between recruited CD11b+ cells and IOP reduction. Conclusions Overall, the results reveal the potential influence of nanoparticle material properties on IOP reduction and inflammatory responses in trabecular meshwork. Such interactions may be critical for the development of future ocular nanodevices with improved safety and perhaps efficacy. PMID:22194895

  6. Determination of Tear Production and Intraocular Pressure With Rebound Tonometry in Wild Humboldt Penguins ( Spheniscus humboldti ).

    Science.gov (United States)

    Sheldon, Julie D; Adkesson, Michael J; Allender, Matthew C; Jankowski, Gwen; Langan, Jennifer; Cardeña, Marco; Cárdenas-Alayza, Susana

    2017-03-01

    Tear production and intraocular pressures (IOPs) were determined in 38 and 102 wild Humboldt penguins (Spheniscus humboldti), respectively, from the Punta San Juan Marine Protected Area in Ica, Peru. Tear production was measured by Schirmer tear test, and IOP was measured with a TonoVet rebound tonometer. Adult (n = 90) and chick (n = 12) penguins were sampled from 2 different beaches (north and south facing) during 2 sampling years (2010 and 2011). Results showed a mean ± SD (range) of 9 ± 4 (2-20) mm/min for tear production and 28 ± 9 (3-49) mm Hg for IOP. Tear production in penguins differed between beach and sex, whereas IOP differed between age, year, and beach. The IOPs were negatively correlated with packed cell volume. Tear production and IOP values had greater variation in this population than it has in other avian species. Previous investigations of IOP and tear production in Spheniscus species were conducted with birds housed under professional care in artificial marine and freshwater environments. This is the first study, to our knowledge, investigating tear production and IOP in wild penguins and establishes valuable reference intervals for this species.

  7. Continuous Intraocular Pressure Monitoring During Nocturnal Sleep in Patients With Obstructive Sleep Apnea Syndrome.

    Science.gov (United States)

    Shinmei, Yasuhiro; Nitta, Takuya; Saito, Hiroshi; Ohguchi, Takeshi; Kijima, Riki; Chin, Shinki; Ishida, Susumu

    2016-05-01

    To evaluate intraocular pressure (IOP) changes during nocturnal sleep in patients with obstructive sleep apnea syndrome (OSAS) using a contact lens sensor (CLS). This was a prospective cohort study. Seven OSAS patients who had no ocular diseases except mild cataract were enrolled. Each subject underwent CLS-based continuous IOP monitoring on one eye simultaneously with overnight polysomnography. We classified the nocturnal IOP records into nonapnea IOP and apnea IOP, according to the duration of apnea events on polysomnography within each IOP measurement time of 30 seconds every 5 minutes. Differences between IOP levels during nonapnea and apnea phases were statistically analyzed. The mean apnea-hypopnea index, the total number of these events per hour of sleep, was 44.2 ± 21.0, indicating the participants' severity of OSAS as moderate to severe. The mean range of IOP fluctuations during nocturnal sleep was 262.3 ± 59.5 mV eq. All patients showed lower mean IOP levels during apnea events than during nonapnea phases, with statistically significant differences detected in four of the seven patients. On average, in all seven eyes, IOP values significantly decreased by 23.1 ± 16.4 mV eq in association with apnea events. Obstructive apnea led to an immediate IOP decline during nocturnal sleep in patients with OSAS. Attention should be paid to IOP-independent etiology, such as episodic hypoxia, potentially linking OSAS and glaucoma.

  8. Safety and efficacy of travoprost solution for the treatment of elevated intraocular pressure.

    Science.gov (United States)

    Quaranta, Luciano; Riva, Ivano; Katsanos, Andreas; Floriani, Irene; Centofanti, Marco; Konstas, Anastasios G P

    2015-01-01

    Travoprost is a prostaglandin analogue widely used for reducing intraocular pressure (IOP) in patients affected with glaucoma and ocular hypertension. It exerts its ocular hypotensive effect through the prostaglandin FP receptors, located in the ciliary muscle and the trabecular meshwork. Several studies have shown that topical administration of travoprost induces a mean IOP reduction ranging from 25% to 32%, and sustained throughout the 24-hour cycle. When compared with timolol, travoprost is more effective at reducing IOP, while generally no difference has been found in the head-to-head comparison with other prostaglandin analogues. The fixed combination of travoprost and timolol has demonstrated a hypotensive efficacy comparable to the concomitant administration of the two drugs. Recently, a new preservative-free formulation of travoprost 0.004% has been marketed for reducing tolerability-related problems in subjects affected with ocular surface disease. Low rates of topical and systemic adverse reactions, strong ocular hypotensive efficacy, and once-a-day dosing make travoprost a first-line treatment for patients affected with elevated IOP.

  9. Relationship between corneal biomechanical properties, central corneal thickness, and intraocular pressure across the spectrum of glaucoma.

    Science.gov (United States)

    Kaushik, Sushmita; Pandav, Surinder Singh; Banger, Anupam; Aggarwal, Kanika; Gupta, Amod

    2012-05-01

    To evaluate corneal biomechanical properties across the glaucoma spectrum and study the relationship between these measurements and intraocular pressure measured by Goldmann applanation tonometry (GAT-IOP) and central corneal thickness (CCT). Prospective cross-sectional study. Tertiary-care teaching institute. A total of 323 eyes of 323 participants (71 normal, 101 glaucoma suspect [GS], 38 ocular hypertension [OHT], 59 primary angle-closure disease [PACD], 36 primary open-angle glaucoma [POAG], and 18 normal-tension glaucoma [NTG]) who had received no ophthalmic treatment. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) measured by the Ocular Response Analyzer (ORA). GAT-IOP and CCT recorded in all subjects. Regression analysis used to determine the relationship between GAT-IOP, CCT, age, CRF, and CH. Bland-Altman plots used to assess agreement between IOP measured by GAT and the ORA (IOPg). CH measurements were significantly less in POAG and NTG compared to normal subjects (P = .034 and P = .030 respectively), regardless of the IOP. The CRF was significantly less in NTG and maximum in POAG and OHT. Regression analysis with CH as dependant variable showed significant association with GAT-IOP and CRF (P glaucoma. CRF appears to influence GAT-IOP measurements more than simple geometric thickness measured by CCT. However, IOP measurements from the ORA are not interchangeable with, and are unlikely to replace, Goldmann applanation tonometry at the present time. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. A randomised comparative study of the effect of Airtraq optical laryngoscope vs. Macintosh laryngoscope on intraocular pressure in non-ophthalmic surgery

    Directory of Open Access Journals (Sweden)

    Bikramjit Das

    2016-02-01

    Full Text Available BACKGROUND: We compared intraocular pressure changes following laryngoscopy and intubation with conventional Macintosh blade and Airtraq optical laryngoscope. METHODS: Ninety adult patients were randomly assigned to study group or control group. Study group (n = 45 - Airtraq laryngoscope was used for laryngoscopy. Control group (n = 45 - conventional Macintosh laryngoscope was used for laryngoscopy. Preoperative baseline intraocular pressure was measured with Schiotz tonometer. Laryngoscopy was done as per group protocol. Intraocular pressure and haemodynamic parameters were recorded just before insertion of the device and subsequently three times at an interval of one minute after insertion of the device. RESULTS: Patient characteristics, baseline haemodynamic parameters and baseline intraocular pressure were comparable in the two groups. Following insertion of the endotracheal tube with Macintosh laryngoscope, there was statistically significant rise in heart rate and intraocular pressure compared to Airtraq group. There was no significant change in MAP. Eight patients in Macintosh group had tongue-lip-dental trauma during intubation, while only 2 patients received upper airway trauma in Airtraq group. CONCLUSION: We conclude that Airtraq laryngoscope in comparison to Macintosh laryngoscope results in significantly fewer rises in intraocular pressure and clinically less marked increase in haemodynamic response to laryngoscopy and intubation.

  11. The relation between intraocular pressure change and plasma natriuretic peptide under simulated hypobaric conditions

    Directory of Open Access Journals (Sweden)

    Karadag Remzi

    2010-01-01

    Full Text Available Purpose: To ascertain whether the changes in intraocular pressure (IOP that occur during hypobaric hypoxic exposure are related to plasma N-terminal pro-brain natriuretic peptide (BNP levels. Materials and Methods: The study group comprised 26 healthy participants (all male, mean age 23.1 years. IOP was measured at local ground level, (792 m above sea level, then while in a chamber providing hypobaric hypoxic conditions (the subjects were exposed to a pressure equivalent to 9144 m for 1-3 min, and again after exit from the chamber. In each condition, the mean of three consecutive measurements of IOP was calculated for each eye. For BNP measurements, blood samples were drawn before the participants entered the chamber and just after they left the chamber. Results: IOP during hypobaric hypoxic exposure (18.00 ± 3.70 mmHg was significantly greater than that before (15.66 ± 2.10 mmHg, P < 0.001 or after (16.10 ± 2.63 mmHg, P = 0.001 the exposure. IOP levels before and after the exposure were not significantly different (P = 0.136. Plasma BNP levels measured before and after exposure to hypobaric hypoxic conditions were not significantly different (P = 0.462. Conclusion: Plasma BNP levels did not change after short-term hypobaric hypoxic exposure, while the IOP increased. This increase may have been caused by some other systemic factors. As the hypobaric hypoxic conditions were reversed, IOP decreased to normal levels.

  12. Association between urinary albumin excretion and intraocular pressure in type 2 diabetic patients without renal impairment.

    Directory of Open Access Journals (Sweden)

    Jin A Choi

    Full Text Available BACKGROUND: To assess the relationship between urinary albumin excretion and intraocular pressure (IOP in type 2 diabetes patients without renal impairment. METHODS: We explored the effects of albuminuria on high IOP in 402 non-glaucomatous type 2 diabetes without renal impairment who participated in the 2011 Korean National Health and Nutrition Examination Survey (KNHANES. Multiple logistic regression analysis was used to assess the relationship between log-transformed albumin/creatinine ratio (ACR tertiles and an IOP of ≥ 18 mmHg after adjusting for age, gender, hypertension, body mass index, triglycerides, area of residence, and education level. RESULTS: Subjects with a high IOP ≥ 18 mmHg were more likely to be current smokers (P = 0.038, heavy drinkers (P = 0.006, and to have high systolic blood pressure (P = 0.016, triglycerides (P = 0.008, and a higher log-transformed ACR (P = 0.022.In multivariate regression analysis, ACR tertile was associated with the prevalence of high IOP significantly (P = 0.022. The associations between ACR tertiles and high IOP were significant in overweight patients and those with abdominal obesity (P = 0.003 and 0.003, respectively. In contrast, there were no associations in the subgroup of patients who were not overweight and those without abdominal obesity (P = 0.291 and 0.561, respectively. CONCLUSIONS: Urinary albumin excretion is associated with high IOP in the type 2 diabetes population without renal insufficiency. The effect of the albuminuria on IOP was evident in a subgroup of patients with components of metabolic syndrome.

  13. Real-time intraocular pressure measurement during phacoemulsification in dogs ex vivo

    Science.gov (United States)

    KANG, Seonmi; PARK, Sangwan; NOH, Hyunwoo; KWAK, Jiyoon; SEO, Kangmoon

    2015-01-01

    This study was performed to evaluate changes in intraocular pressure (IOP) during standard coaxial phacoemulsification using 4 different bottle heights (BHs) and 2 different incision sizes. Coaxial phacoemulsification was performed with a venturi-based machine in 8 enucleated canine eyes through 3.0 and 3.2 mm clear corneal incisions (CCIs). A pressure transducer inserted in the peripheral cornea monitored the IOP in real-time. The surgery was subdivided into 4 stages: sculpt-segment removal, irrigation/aspiration, capsular polishing and viscoelastic removal. The mean IOP and the difference between the maximum and minimum IOPs were calculated at each stage and compared. The ultrasound time and volume of irrigation fluid used were recorded. The mean IOP increased with an elevation in the BH. The mean IOP in the irrigation/aspiration stage was significantly higher than that in the sculpt-segment removal stage at the same BH. The difference between the maximum and minimum IOP at each stage was greater in the 3.2 mm than the 3.0 mm CCIs, although the mean IOP was lower with the 3.2 mm than the 3.0 mm CCIs. The ultrasound time and irrigation fluid volume were greater with the 3.2 mm than the 3.0 mm CCIs. Therefore, fluidic parameters during each stage could be reassessed and adjusted to reduce complications arising from an elevated IOP. Phacoemulsification with 3.0 mm CCIs at a lower BH might lead to less stress on the eye from IOP fluctuations, ultrasound energy and irrigation fluid. PMID:25716691

  14. Allometry and Scaling of the Intraocular Pressure and Aqueous Humour Flow Rate in Vertebrate Eyes

    Science.gov (United States)

    Zouache, Moussa A.; Eames, Ian; Samsudin, Amir

    2016-01-01

    In vertebrates, intraocular pressure (IOP) is required to maintain the eye into a shape allowing it to function as an optical instrument. It is sustained by the balance between the production of aqueous humour by the ciliary body and the resistance to its outflow from the eye. Dysregulation of the IOP is often pathological to vision. High IOP may lead to glaucoma, which is in man the second most prevalent cause of blindness. Here, we examine the importance of the IOP and rate of formation of aqueous humour in the development of vertebrate eyes by performing allometric and scaling analyses of the forces acting on the eye during head movement and the energy demands of the cornea, and testing the predictions of the models against a list of measurements in vertebrates collated through a systematic review. We show that the IOP has a weak dependence on body mass, and that in order to maintain the focal length of the eye, it needs to be an order of magnitude greater than the pressure drop across the eye resulting from gravity or head movement. This constitutes an evolutionary constraint that is common to all vertebrates. In animals with cornea-based optics, this constraint also represents a condition to maintain visual acuity. Estimated IOPs were found to increase with the evolution of terrestrial animals. The rate of formation of aqueous humour was found to be adjusted to the metabolic requirements of the cornea, scaling as Vac0.67, where Vac is the volume of the anterior chamber. The present work highlights an interdependence between IOP and aqueous flow rate crucial to ocular function that must be considered to understand the evolution of the dioptric apparatus. It should also be taken into consideration in the prevention and treatment of glaucoma. PMID:26990431

  15. Evaluation of a new rebound tonometer for self-measurement of intraocular pressure.

    Science.gov (United States)

    Dabasia, Priya L; Lawrenson, John G; Murdoch, Ian E

    2016-08-01

    To compare the accuracy of self-obtained, partner-obtained and trainer-obtained measurements using the handheld Icare Home rebound tonometer with Goldmann applanation tonometry (GAT), and to evaluate the acceptability to subjects of Icare Home measurement. 76 subjects were trained to use Icare Home for self-measurement using a standardised protocol. A prespecified checklist was used to assess the ability of a subject to perform self-tonometry. Accuracy of Icare Home self-measurement was compared with GAT using one eye per subject, randomly selected. Bland-Altman difference analysis was used to compare Icare Home and GAT intraocular pressure (IOP) estimates. Acceptability of self-tonometry was evaluated using a questionnaire. 56 subjects (74%, 95% CI 64 to 84) were able to correctly perform self-tonometry. Mean bias (95% limits of agreement) was 0.3 mm Hg (-4.6 to 5.2), 1.1 mm Hg (-3.2 to 5.3) and 1.2 mm Hg (-3.9 to 6.3) for self-assessment, partner-assessment and trainer-assessment, respectively, suggesting underestimation of IOP by Icare Home tonometry. Differences between GAT and Icare Home IOP were greater for central corneal thickness below 500 µm and above 600 µm than data points within this range. Acceptability questionnaire responses showed high agreement that the self-pressure device was easy to use (84%), the reading was quick to obtain (88%) and the measurement was comfortable (95%). Icare Home tonometry can be used for self-measurement by a majority of trained subjects. IOP measurements obtained using Icare Home tonometry by self-assessment and third party-assessment showed slight underestimation compared with GAT. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  16. Intraocular pressure following 18 hours of systemic dehydration in ocular normotensive healthy subjects

    Directory of Open Access Journals (Sweden)

    Faustina K. Idu

    2015-03-01

    Full Text Available Aim: To investigate the effect of dehydration on intraocular pressure (IOP. Subjects: The study population comprised 50 subjects (27 men and 23 women with a mean age of 42.84 ± 2.64 years.Method: The subjects dehydrated for 18 hours. IOP was assessed in both eyes using the Perkins handheld applanation tonometer. Baseline measurement of IOP was taken before the subjects dehydrated for 18 hours and repeated after dehydration. Blood samples were taken before and after dehydration for the determination of plasma osmolality and plasma antidiuretic hormone (ADH concentrations.Results: A statistically significant (p < 0.001 reduction in the mean weight of subjects occurred after dehydration. There was a significant reduction in IOP from 16.68 mmHg ± 0.32 mmHg to 13.08 mmHg ± 0.31 mmHg after dehydration (p < 0.001. Mean plasma osmolality showed a statistically significant increase (p < 0.05 from baseline of 290.02 mOsmol/kg ± 1.25 mOsmol/kg to 294.96 mOsmol/kg ± 1.33 mOsmol/kg after dehydration. There was also a significant increase (p < 0.05 in mean plasma ADH concentration from 5.36 pg/mL ± 0.21 pg/mL to 6.40 pg/mL ± 0.20 pg/mL after dehydration. There were no significant differences in both systolic and diastolic blood pressures before and after dehydration.Conclusion: Dehydration decreases IOP in healthy humans; this decrease probably results from an increase in plasma osmolality and plasma ADH concentrations.

  17. The 24-Hour Effects of Brinzolamide/Brimonidine Fixed Combination and Timolol on Intraocular Pressure and Ocular Perfusion Pressure.

    Science.gov (United States)

    Seibold, Leonard K; DeWitt, Peter E; Kroehl, Miranda E; Kahook, Malik Y

    2017-04-01

    To determine the 24-h effects of brinzolamide/brimonidine tartrate 1%/0.2% fixed combination (BBFC) on intraocular pressure (IOP), ocular perfusion pressure (OPP), blood pressure (BP), and heart rate (HR). Sixty subjects with open angle glaucoma (OAG) or ocular hypertension (OHTN) were admitted overnight for 24-h monitoring of IOP, BP, and HR. All subjects underwent the first, baseline 24-h study after washout of all medications, if necessary. Subjects were then randomized to receive either (1) timolol maleate 0.5% twice daily or (2) BBFC 3 times daily. After 4 weeks of treatment, all subjects completed a follow-up 24-h study visit. At each study visit, IOP, BP, and HR were measured every 2 h in the habitual position. OPP was calculated as 2/3[diastolic BP +1/3(systolic BP-diastolic BP)]-IOP. Treatment with BBFC significantly lowered IOP during the diurnal period (-2.7 ± 0.4 mmHg; P < 0.01) and nocturnal period (-0.8 ± 0.3 mmHg; P < 0.01). Timolol similarly reduced IOP during the diurnal period, but did not lower IOP overnight. Over a 24-h period, BBFC achieved a significantly greater IOP reduction than timolol (-0.7 ± 0.4 mmHg; P = 0.04). BBFC failed to achieve an increase in OPP during any time period, while timolol increased OPP during the diurnal period only. A significantly greater reduction in HR occurred in the timolol group. BBFC significantly lowers IOP during both the diurnal and nocturnal periods, but has no effect on OPP. Timolol only lowers IOP during the diurnal period.

  18. Effects of timolol maleate, levobunolol and apraclonidine on intraocular pressure, pupil size, blood pressure and heart rate in beagles

    Directory of Open Access Journals (Sweden)

    I.R.M. Padua

    2016-06-01

    Full Text Available ABSTRACT The aim of this study was to evaluate changes in intraocular pressure (IOP, pupil size (PS, blood pressure (BP, heart rate (HR, and ECG variables (Pms wave PmV, PR interval, QRS complex, RMV wave and QT intervals over time during the instillation of 0.5% timolol, 0.5% levobunolol and 0.5% apraclonidine in clinically normal dogs. Ten adult beagles were used. Baseline values were measured at 8a.m., 2p.m. and 8p.m., for three consecutive days. A waiting period of 10 days between the administrations of each drug was established. For 15 consecutive days, the drug being tested was instilled in one eye of each dog twice a day (7a.m. and 7p.m.. The parameters were evaluated at the aforementioned times on days 3, 6, 9, 12 and 15. Data were statistically compared using the Bonferroni test and one-way repeated measures analysis of variance (P<0.05. The Pearson test was used to evaluate any correlation between QT interval, HR and BP. The tested drugs did not find a decrease in IOP. A significant decreased in PS was observed in almost all dogs following levobunolol administration, relative to the control eye. A significant decrease in HR was observed on day 3 following levobunolol treatment, while apraclonidine induced an increase on day 15. Blood pressure was reduced in all measurement time points following apraclonidine treatment. A negative correlation between QT interval and HR was only observed in dogs treated with timolol. In conclusion, levobunolol was the only drug that induced significant alterations in PS. Apraclonidine was the only drug that induced systemic hypotension. Timolol was the only drug to that induced a negative correlation between QT and HR.

  19. Evaluation of continuous 24-hour intraocular pressure monitoring for assessment of prostaglandin-induced pressure reduction in glaucoma.

    Science.gov (United States)

    Holló, Gábor; Kóthy, Péter; Vargha, Péter

    2014-01-01

    To evaluate 24-hour continuous intraocular pressure (IOP) monitoring with a telemetric contact lens sensor (CLS) to detect prostaglandin-induced IOP reduction. In this prospective interventional study 9 ocular hypertensive and primary open-angle glaucoma patients were washed out from IOP-lowering medication for 6 weeks. One study eye per patient underwent 3 baseline 24-hour measurement curves 4 days apart: 2 curves with Sensimed Triggerfish CLS and 1 curve with Goldmann applanation tonometry (GAT). Then the patients received travoprost monotherapy for 3 months. The 24-hour CLS and GAT curves were repeated on the study eyes under treatment at the end of the third month. The 24-hour GAT IOP (mean±SD) decreased from 22.91±5.11 to 18.24±2.49 mm Hg (P0.05). Our results suggest that the current CLS technique cannot be clinically used to monitor IOP decrease induced by topical medication in glaucoma, and has limited value in identification of transient IOP elevation periods.

  20. Effect of caffeine on the intraocular pressure in patients with primary open angle glaucoma

    Directory of Open Access Journals (Sweden)

    Chandra P

    2011-11-01

    Full Text Available Peeyush Chandra1, Ajit Gaur1, Shambhu Varma21Chandra Eye Research Institute, Allahabad, UP, India; 2Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, MD, USAPurpose: Coffee and tea are very common nonalcoholic beverages. However, their intake, particularly that of coffee, has been suggested to increase intraocular pressure (IOP in patients with open angle glaucoma/ocular hypertension. The causative agent has been suggested to be their caffeine content. The objective of this study was to determine if this represents a direct caffeine effect. This study was therefore done using pure caffeine applied directly to the eyes.Methods: The study was conducted with five human volunteers with open angle glaucoma/ocular hypertension. IOP was measured using a Perkins applanation tonometer. Eye drops of 1% caffeine were prepared in-home. Following the initial (basal measurement of the IOP, 50 µL of the eye drop preparation was instilled in the eye at 0-, 4-, and 6-hour intervals. IOPs were measured 30 minutes after each instillation. A second study was also undertaken following the first. In this study, the same patients instilled the eye drops three times per day for 1 week at home and then returned to the clinic on day 7. They were then again treated with caffeine eye drops as above and IOPs measured.Results: In the 1-day study, the mean basal IOP was 23.6 ± 2.80 mmHg. Thirty minutes after instillation of the drops as described, the pressures were 23.2 ± 1.93, 22.2 ± 1.99, and 22.6 ± 2.31. The basal reading was taken at 10 am and another reading was then taken at 10.30 am. Additional eye drops were instilled at 2 and 8 pm and readings taken 30 minutes after each instillation. In the 1 week study, the basal value was 22.6 ± 2.32. After instillation of the drops as above the values were 23 ± 2.16, 22.4 ± 2.27, and 23 ± 1.94.Conclusion: Administration of caffeine into the eyes of patients did not

  1. System for Rapid, Precise Modulation of Intraocular Pressure, toward Minimally-Invasive In Vivo Measurement of Intracranial Pressure.

    Directory of Open Access Journals (Sweden)

    Max A Stockslager

    Full Text Available Pathologic changes in intracranial pressure (ICP are commonly observed in a variety of medical conditions, including traumatic brain injury, stroke, brain tumors, and glaucoma. However, current ICP measurement techniques are invasive, requiring a lumbar puncture or surgical insertion of a cannula into the cerebrospinal fluid (CSF-filled ventricles of the brain. A potential alternative approach to ICP measurement leverages the unique anatomy of the central retinal vein, which is exposed to both intraocular pressure (IOP and ICP as it travels inside the eye and through the optic nerve; manipulating IOP while observing changes in the natural pulsations of the central retinal vein could potentially provide an accurate, indirect measure of ICP. As a step toward implementing this technique, we describe the design, fabrication, and characterization of a system that is capable of manipulating IOP in vivo with <0.1 mmHg resolution and settling times less than 2 seconds. In vitro tests were carried out to characterize system performance. Then, as a proof of concept, we used the system to manipulate IOP in tree shrews (Tupaia belangeri while video of the retinal vessels was recorded and the caliber of a selected vein was quantified. Modulating IOP using our system elicited a rapid change in the appearance of the retinal vein of interest: IOP was lowered from 10 to 3 mmHg, and retinal vein caliber sharply increased as IOP decreased from 7 to 5 mmHg. Another important feature of this technology is its capability to measure ocular compliance and outflow facility in vivo, as demonstrated in tree shrews. Collectively, these proof-of-concept demonstrations support the utility of this system to manipulate IOP for a variety of useful applications in ocular biomechanics, and provide a framework for further study of the mechanisms of retinal venous pulsation.

  2. The Effect of a Diving Mask on Intraocular Pressure in a Healthy Population

    Directory of Open Access Journals (Sweden)

    Catherina Josephine Goenadi

    2016-06-01

    Full Text Available Purpose: Swimming goggles increase the intraocular pressure (IOP via the periorbital frame pressure and suction effect. In comparison, diving masks have a larger frame rim and incorporate the nose. The exact effect(s of diving masks on IOP is unknown. This study evaluates the influence of diving masks on IOP in normal, healthy subjects. Methods: Tonometry was performed in both eyes of all subjects with an AVIA®Tono-Pen by a single investigator. Measurements were taken at baseline without the diving mask and with the subjects wearing a small-volume, double-window diving mask, but with the mask lenses removed. Two IOP readings in each eye were measured, and an additional reading was measured if the difference between the initial 2 was ≥2 mm Hg. Central corneal thickness (CCT was also measured in each eye, using a contact pachymeter (OcuScan®Alcon. Results: Forty eyes of 20 healthy volunteers (age 29.7 ± 9.3 years; range 21–52 were included. The mean CCT was 544.4 ± 43.5 µm. The mean IOP before the diving mask was worn had been 17.23 ± 2.18 mm Hg (n = 40. The IOP decreased by 0.43 mm Hg (p < 0.05 to 16.80 ± 2.57 mm Hg after the diving mask had been put on. There was no correlation between IOP change and age (r = 0.143, p = 0.337, gender (r = –0.174, p = 0.283 or CCT (r = –0.123, p = 0.445. Conclusion: There was no increase in IOP after the diving mask had been worn. A small but statistically significant decrease in IOP was observed. This study demonstrates that unlike swimming goggles, the strap tension and frame pressure on the periorbital tissue from a diving mask does not increase IOP. Diving masks may be a suitable alternative to swimming goggles for patients with advanced glaucoma or glaucoma filtration surgery.

  3. The Effect of a Diving Mask on Intraocular Pressure in a Healthy Population.

    Science.gov (United States)

    Goenadi, Catherina Josephine; Law, David Zhiwei; Lee, Jia Wen; Ong, Ee Lin; Chee, Wai Kitt; Cheng, Jason

    2016-01-01

    Swimming goggles increase the intraocular pressure (IOP) via the periorbital frame pressure and suction effect. In comparison, diving masks have a larger frame rim and incorporate the nose. The exact effect(s) of diving masks on IOP is unknown. This study evaluates the influence of diving masks on IOP in normal, healthy subjects. Tonometry was performed in both eyes of all subjects with an AVIA(®)Tono-Pen by a single investigator. Measurements were taken at baseline without the diving mask and with the subjects wearing a small-volume, double-window diving mask, but with the mask lenses removed. Two IOP readings in each eye were measured, and an additional reading was measured if the difference between the initial 2 was ≥2 mm Hg. Central corneal thickness (CCT) was also measured in each eye, using a contact pachymeter (OcuScan(®)Alcon). Forty eyes of 20 healthy volunteers (age 29.7 ± 9.3 years; range 21-52) were included. The mean CCT was 544.4 ± 43.5 µm. The mean IOP before the diving mask was worn had been 17.23 ± 2.18 mm Hg (n = 40). The IOP decreased by 0.43 mm Hg (p $1003c; 0.05) to 16.80 ± 2.57 mm Hg after the diving mask had been put on. There was no correlation between IOP change and age (r = 0.143, p = 0.337), gender (r = -0.174, p = 0.283) or CCT (r = -0.123, p = 0.445). There was no increase in IOP after the diving mask had been worn. A small but statistically significant decrease in IOP was observed. This study demonstrates that unlike swimming goggles, the strap tension and frame pressure on the periorbital tissue from a diving mask does not increase IOP. Diving masks may be a suitable alternative to swimming goggles for patients with advanced glaucoma or glaucoma filtration surgery.

  4. Effect of postural change on intraocular pressure fluctuation in open angle glaucoma patients after trabeculectomy

    Directory of Open Access Journals (Sweden)

    Wei Li

    2015-02-01

    Full Text Available AIM:To study the effect of postural change on intraocular pressure(IOPfluctuation in open angle glaucoma patients after trabeculectomy, and to discuss the value of this investigation on prognosis. METHODS: Fifty-one cases(62 eyesof primary open angle glaucoma were selected as the research object. Perkins ophthalmotonometer was used to test IOP at the time when patient seat(first seat. The patients were asked to lie supine for 25min, detected IOP, and the patients seated again(final seat, sustaining for 15min, detected IOP. According to whether the IOP range was more than 5mmHg, they were divided into high volatility fluctuation group and low volatility fluctuation group. We recorded their visual field progression(with AGIS score, HPA staging, in order to evaluate the correlation of IOP range with them. Reviews were made 3mo a time, and lasted for 1a, in order to evaluate the relation between IOP range and AGIS scores.RESULTS: The IOP of first seat was 18.1+2.2mmHg. There was no significant difference in the same position(P>0.05. The IOP range was 4.1±1.5mmHg. Low volatility fluctuation group was more likely to have low AGIS score and to be early vision HPA(PPr=0.412, PPCONCLUSION: Visual field progression is related to the degree of IOP fluctuation in open angle glaucoma patients after trabeculectomy, so we can predict the prognosis of patients simply by detect IOP fluctuation. This is good to adjust the IOP control scheme.

  5. 28-day intraocular pressure reduction with a single dose of brimonidine tartrate-loaded microspheres.

    Science.gov (United States)

    Fedorchak, Morgan V; Conner, Ian P; Medina, Carlos A; Wingard, Jeremy B; Schuman, Joel S; Little, Steven R

    2014-08-01

    Treatment of glaucoma by intraocular pressure (IOP) reduction is typically accomplished through the administration of eye drops, the difficult and frequent nature of which contributes to extremely low adherence rates. Poor adherence to topical treatment regimens in glaucoma patients can lead to irreversible vision loss and increased treatment costs. Currently there are no approved treatments for glaucoma that address the inherent inefficiencies in drug delivery and patient adherence. Brimonidine tartrate (BT), a common glaucoma medication, requires dosing every 8-12 h, with up to 97% of patients not taking it as prescribed. This study provides proof-of-principle testing of a controlled release BT formulation. BT was encapsulated in poly(lactic-co-glycolic) acid microspheres and drug release was quantified using UV-Vis spectroscopy. For in vivo studies, rabbits were randomized to receive a single subconjunctival injection of blank (no drug) or BT-loaded microspheres or twice daily topical 0.2% BT drops. The microspheres released an average of 2.1 ± 0.37 μg BT/mg microspheres/day in vitro. In vivo, the percent decrease in IOP from baseline was significantly greater in the treated eye for both topical drug and drug-loaded microspheres versus blank microspheres throughout the 4-week study, with no evidence of migration or foreign body response. IOP measurements in the contralateral, untreated eyes also suggested a highly localized effect from the experimental treatment. A treatment designed using the release systems described in this study would represent a vast improvement over the current clinical standard of 56-84 topical doses over 28 days. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Ocular biometric parameters associated with intraocular pressure reduction after cataract surgery in normal eyes.

    Science.gov (United States)

    Yang, Hyun Seung; Lee, Junsung; Choi, Sangkyung

    2013-07-01

    To evaluate the ocular biometric parameters associated with intraocular pressure (IOP) reduction after phacoemulsification. Prospective, observational case series. The study included 999 patients who had undergone uncomplicated phacoemulsification. IOP and ocular biometric parameters were checked preoperatively and 3 months postoperatively using anterior segment optical coherence tomography, optical biometry, and ultrasonic biomicroscopy. The relationship between IOP change and the parameters, including preoperative IOP, anterior chamber depth, axial length, angle opening distance at 500 μm, anterior chamber area, corneal thickness, lens thickness, and iris thickness at 750 μm, was evaluated. The mean patient age was 67.1 ± 4.3 years. The average change in IOP was -1.6 mm Hg (-11.8%). In univariate analysis, axial length, corneal thickness, and iris thickness were not significantly associated with IOP reduction. However, preoperative IOP, anterior chamber depth, angle opening distance, anterior chamber area, and lens thickness were significantly associated with IOP change (P < .05). Furthermore, changes in anterior chamber depth (standardized coefficient beta [B] = -0.082), angle opening distance (B = -0.095), and anterior chamber area (B = -0.380) were more strongly correlated with IOP change than were preoperative factors (B = -0.078, B = -0.071, and B = -0.067, respectively). In multivariate analysis, preoperative IOP, lens thickness, angle opening distance change, and anterior chamber area change were significantly associated with IOP change (P < .005). In addition to preoperative IOP and lens thickness, parameters such as changes in anterior chamber area and angle opening distance were significantly associated positively with reduced IOP after phacoemulsification. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Intraocular pressure in genetically distinct mice: an update and strain survey

    Directory of Open Access Journals (Sweden)

    Tomarev Stanislav I

    2001-08-01

    Full Text Available Abstract Background Little is known about genetic factors affecting intraocular pressure (IOP in mice and other mammals. The purpose of this study was to determine the IOPs of genetically distinct mouse strains, assess the effects of factors such as age, sex and time of day on IOP in specific strain backgrounds, and to assess the effects of specific candidate gene mutations on IOP. Results Based on over 30 studied mouse strains, average IOP ranges from approximately 10 to 20 mmHg. Gender does not typically affect IOP and aging results in an IOP decrease in some strains. Most tested strains exhibit a diurnal rhythm with IOP being the highest during the dark period of the day. Homozygosity for a null allele of the carbonic anhydrase II gene (Car2n does not alter IOP while homozygosity for a mutation in the leptin receptor gene (Leprdb that causes obesity and diabetes results in increased IOP. Albino C57BL/6J mice homozygous for a tyrosinase mutation (Tyrc-2J have higher IOPs than their pigmented counterparts. Conclusions Genetically distinct mouse strains housed in the same environment have a broad range of IOPs. These IOP differences are likely due to interstrain genetic differences that create a powerful resource for studying the regulation of IOP. Age, time of day, obesity and diabetes have effects on mouse IOP similar to those in humans and other species. Mutations in two of the assessed candidate genes (Lepr and Tyr result in increased IOP. These studies demonstrate that mice are a practical and powerful experimental system to study the genetics of IOP regulation and disease processes that raise IOP to harmful levels.

  8. Autotaxin-lysophosphatidic acid axis is a novel molecular target for lowering intraocular pressure.

    Directory of Open Access Journals (Sweden)

    Padma Iyer

    Full Text Available Primary open-angle glaucoma is the second leading cause of blindness in the United States and is commonly associated with elevated intraocular pressure (IOP resulting from diminished aqueous humor (AH drainage through the trabecular pathway. Developing effective therapies for increased IOP in glaucoma patients requires identification and characterization of molecular mechanisms that regulate IOP and AH outflow. This study describes the identification and role of autotaxin (ATX, a secretory protein and a major source for extracellular lysophosphatidic acid (LPA, in regulation of IOP in a rabbit model. Quantitative proteomics analysis identified ATX as an abundant protein in both human AH derived from non-glaucoma subjects and in AH from different animal species. The lysophospholipase D (LysoPLD activity of ATX was found to be significantly elevated (by ∼1.8 fold; n=20 in AH derived from human primary open angle glaucoma patients as compared to AH derived from age-matched cataract control patients. Immunoblotting analysis of conditioned media derived from primary cultures of human trabecular meshwork (HTM cells has confirmed secretion of ATX and the ability of cyclic mechanical stretch of TM cells to increase the levels of secreted ATX. Topical application of a small molecular chemical inhibitor of ATX (S32826, which inhibited AH LysoPLD activity in vitro (by >90%, led to a dose-dependent and significant decrease of IOP in Dutch-Belted rabbits. Single intracameral injection of S32826 (∼2 µM led to significant reduction of IOP in rabbits, with the ocular hypotensive response lasting for more than 48 hrs. Suppression of ATX expression in HTM cells using small-interfering RNA (siRNA caused a decrease in actin stress fibers and myosin light chain phosphorylation. Collectively, these observations indicate that the ATX-LPA axis represents a potential therapeutic target for lowering IOP in glaucoma patients.

  9. Pigmented and albino rats differ in their responses to moderate, acute and reversible intraocular pressure elevation.

    Science.gov (United States)

    Gurdita, Akshay; Tan, Bingyao; Joos, Karen M; Bizheva, Kostadinka; Choh, Vivian

    2017-06-01

    To compare the electrophysiological and morphological responses to acute, moderately elevated intraocular pressure (IOP) in Sprague-Dawley (SD), Long-Evans (LE) and Brown Norway (BN) rat eyes. Eleven-week-old SD (n = 5), LE (n = 5) and BN (n = 5) rats were used. Scotopic threshold responses (STRs), Maxwellian flash electroretinograms (ERGs) or ultrahigh-resolution optical coherence tomography (UHR-OCT) images of the rat retinas were collected from both eyes before, during and after IOP elevation of one eye. IOP was raised to ~35 mmHg for 1 h using a vascular loop, while the other eye served as a control. STRs, ERGs and UHR-OCT images were acquired on 3 days separated by 1 day of no experimental manipulation. There were no significant differences between species in baseline electroretinography. However, during IOP elevation, peak positive STR amplitudes in LE (mean ± standard deviation 259 ± 124 µV) and BN (228 ± 96 µV) rats were about fourfold higher than those in SD rats (56 ± 46 µV) rats (p = 0.0002 for both). Similarly, during elevated IOP, ERG b-wave amplitudes were twofold higher in LE and BN rats compared to those of SD rats (947 ± 129 µV and 892 ± 184 µV, vs 427 ± 138 µV; p = 0.0002 for both). UHR-OCT images showed backward bowing in all groups during IOP elevation, with a return to typical form about 30 min after IOP elevation. Differences in the loop-induced responses between the strains are likely due to different inherent retinal morphology and physiology.

  10. Apraclonidine versus brinzolamide-timolol combination to prevent intraocular pressure elevation after laser capsulotomy

    Directory of Open Access Journals (Sweden)

    Erkan Çelik

    2016-01-01

    Full Text Available AIM: To compare the efficacy of fixed combination of brinzolamide 1% and timolol 0.5%(FCBTwith apraclonidine 0.5%(APRAin preventing intraocular pressure(IOPelevations after neodymium: yttrium-aluminum-garnet(Nd:YAGlaser posterior capsulotomy.METHODS: This prospective randomized clinical study included 90 eyes of 90 consecutive patients who had Nd:YAG laser posterior capsulotomy for posterior capsule opacification(PCO. Patients were randomized to receive APRA(n=45or FCBT(n=45at 1h before laser surgery. A masked observer measured IOP by Goldmann applanation tonometry before the procedure and at 1, 2, 3, 24h and 7d after laser treatment. IOP outcome measures were grouped into the following categories: post laser IOP elevation of 5 to RESULTS:The mean IOP before surgery on the day of the procedure was 14.1±2.1 mm Hg in the APRA group and 13.2±2.1 mm Hg in the FCBT group. There was no statistically significant difference between the APRA and the FCBT groups of baseline IOPs measured(P=0.066. During the follow-up time, the mean IOP was lower in FCBT group, but this was not statistically significant. Six patients(13.3%in APRA group and 4(8.9%in FCBT group had IOP elevations of 5 to P=0.243. IOP elevations of 10 mm Hg or more occurred in 3 eyes(6.7%in the APRA group and 1 eyes(2.2%in the FCBT group; this was not statistically significant(P=0.542. CONCLUSION:Both of APRA and FCBT are effective for prevention and APRA is enough for most of routine cases. FCBT may be an option for the eyes those need more IOP reduction such as pre-existing glaucoma patients who are at higher risk for postoperative IOP elevations.

  11. Comparison of three intraocular pressure measurement methods including biomechanical properties of the cornea.

    Science.gov (United States)

    Smedowski, Adrian; Weglarz, Beata; Tarnawska, Dorota; Kaarniranta, Kai; Wylegala, Edward

    2014-02-04

    The aim of this study was to show the usefulness of three methods for measuring IOP: Goldmann applanation tonometry, rebound tonometry, and Ultra-High-Speed Scheimpflug technology. The examined group consisted of 96 patients (192 eyes), including 63 women and 33 men with a mean age of 59.3 ± 19.9 years. Together, 152 healthy eyes and 40 eyes with different pathologies were examined. Intraocular pressure was measured using the Goldmann applanation tonometer (GAT), the Icare Pro rebound tonometer (RT), and Ultra-High-Speed Scheimpflug technology (UHS ST; Corvis ST with pachymetry). Additionally, corneal pachymetry was conducted with a Scheimpflug camera (Pentacam) and an Ultrasound Pachymeter (A-scan Plus) as a comparison for Corvis ST pachymetry. The mean IOPs were 15.6 ± 3.75 mm Hg, 15.6 ± 3.5 mm Hg, and 16.1 ± 4.0 mm Hg when measured with the GAT, the RT, and the UHS ST, respectively. The mean central corneal thickness (CCT) was 543.7 ± 52.7 μm, 547.9 ± 54.0 μm, and 556.25 ± 38.8 μm as measured with the UHS ST, the Pentacam, and the Ultrasound Pachymeter, respectively. In comparison between devices, there was a significant difference between IOP values measured with the GAT and the RT versus the UHS ST (P < 0.001), and there was no significant difference between GAT and RT (P = 0.5). No significant differences were observed in CCT measured with the UHS ST, Pentacam, and Ultrasound Pachymeter. We showed that the RT Icare Pro ensures IOP measurements that are more comparable with the measurements obtained with the GAT than the measurements that are provided by UHS ST.

  12. Evaulation of Incidence and Risk Factors for Intraocular Pressure Elevation After Intravitreal Triamcinolone Acetonide Injection

    Directory of Open Access Journals (Sweden)

    Didar Uçar

    2015-05-01

    Full Text Available Objectives: To investigate the effect of intravitreal triamcinolone acetonide (IVTA used for the macular edema on intraocular pressure (IOP and to determine the risk factors for IOP elevation. Materials and Methods: This retrospective study included 93 eyes of 85 patients who had 4 mg intravitreal triamcinolone injection. Of the 85 patients, 56 (65.8% had diabetic macular edema, 22 (25.8% had branch retinal, and 7 (8.2% had central retinal vein occlusion. IOP changes after injection as well as the relation between IOP elevation and age, sex, lens status, etiology of macular edema, baseline IOP were evaluated. Results: Fourty-six male and 39 female patients with mean age 61.58±9.5 years were evaluated. IOP was recorded to be >24 mmHg in 30 eyes (32.2% at follow-up visit after an average of 7.5 weeks. Normalization of IOP with medication was achieved in all IOP elevated eyes. Fifteen of 29 eyes (51.7% with vein occlusion and 15 of 64 eyes (23.3% with diabetic macula edema had IOP elevation (p=0.01. Twenty-six of 73 phakic (35.6% and 4 of 20 pseudophakic eyes (20% had IOP >24 mmHg (p=0.16. There was no association between IOP elevation and sex (p=0.33. Baseline IOP was 16.47±2.8 mmHg in eyes which had elevated IOP and 14.78±2.4 mmHg in the remaining. There was significant relation between IOP elevation and baseline IOP level (p=0.01. Conclusion: Elevated IOP is common side effect after IVTA, but normalization is usually achieved by topical medication. Patients with baseline IOP ≥15 mmHg and vein occlusion have higher risk for IOP elevation. (Turk J Ophthalmol 2015; 45: 86-91

  13. Haploinsufficient Bmp4 ocular phenotypes include anterior segment dysgenesis with elevated intraocular pressure

    Directory of Open Access Journals (Sweden)

    Nusinowitz Steven

    2001-11-01

    Full Text Available Abstract Background Glaucoma is a blinding disease usually associated with high intraocular pressure (IOP. In some families, abnormal anterior segment development contributes to glaucoma. The genes causing anterior segment dysgenesis and glaucoma in most of these families are not identified and the affected developmental processes are poorly understood. Bone morphogenetic proteins (BMPs participate in various developmental processes. We tested the importance of Bmp4 gene dosage for ocular development and developmental glaucoma. Results Bmp4+/- mice have anterior segment abnormalities including malformed, absent or blocked trabecular meshwork and Schlemm's canal drainage structures. Mice with severe drainage structure abnormalities, over 80% or more of their angle's extent, have elevated IOP. The penetrance and severity of abnormalities is strongly influenced by genetic background, being most severe on the C57BL/6J background and absent on some other backgrounds. On the C57BL/6J background there is also persistence of the hyaloid vasculature, diminished numbers of inner retinal cells, and absence of the optic nerve. Conclusions We demonstrate that heterozygous deficiency of BMP4 results in anterior segment dysgenesis and elevated IOP. The abnormalities are similar to those in human patients with developmental glaucoma. Thus, BMP4 is a strong candidate to contribute to Axenfeld-Rieger anomaly and other developmental conditions associated with human glaucoma. BMP4 also participates in posterior segment development and wild-type levels are usually critical for optic nerve development on the C57BL/6J background. Bmp4+/- mice are useful for studying various components of ocular development, and may allow identification of strain specific modifiers affecting a variety of ocular phenotypes.

  14. The correlation between body mass index and intraocular pressure in children

    Directory of Open Access Journals (Sweden)

    Luciano Lira de Albuquerque

    2013-02-01

    Full Text Available PURPOSE: There is evidence from some studies that support an association between obesity in adults and higher intraocular pressure (IOP. However, this association has not been completely studied in children. Our aim is to evaluate the association between child body mass index (BMI and IOP. METHODS: Ninety-six children attending the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP in Brazil were studied. Thirty-three were overweight/obese with a mean BMI of 29.7 ± 5.2 and 63 with a mean BMI of 20.8 ± 3.3. IOP was measured using the Goldmann applanation tonometer and was corrected for corneal thickness. The coefficient of correlation between BMI and IOP was calculated. RESULTS: There was no significant difference in the IOP of children with or without overweight/obesity. The mean IOP was 13.5 and 13.0 mmHg for the right eye and 13.1 and 12.9 mmHg for left eye, respectively (p=0.38 and p=0.71. The results remained the same after correction by pachymetry; 13.0 and 13.1 mmHg for the right eye and 12.4 and 12.9 mmHg for the left eye, respectively (p=0.88 and p=0.41. The coefficient of correlation between BMI and IOP was 0.070 (p=0.496. CONCLUSION: These results do not show a correlation between body mass index and IOP in children. Further studies are warranted to clarify the association between BMI and IOP in children.

  15. [Alterations in intraocular pressure and the CorVis parameters after LASIK].

    Science.gov (United States)

    Anton, A; Neuburger, M; Jordan, J F; Wecker, T; Lübke, J; Heinzelmann, S; Lapp, T; Böhringer, D; Reinhard, T; Maier, P

    2017-05-01

    The reduction of corneal thickness following laser-assisted in-situ keratomileusis (LASIK) requires a correction of intraocular pressure (IOP) measurements. The corneal visualization Scheimpflug technology (CorVis ST, Oculus, Wetzlar, Germany) not only measures the IOP and central corneal thickness (CCT) but also determines 10 additional corneal parameters, such as the time to first and second applanation and velocity. Besides CCT we compared various corneal parameters before and after LASIK in order to detect possible correlations and to correct IOP measurements. Measurements with CorVis ST were made before and after LASIK in 45 myopic patients (45 left eyes). We compared the IOP and CorVis ST parameters using a paired t‑test before and after LASIK and corrected for possible correlations in a multifactorial linear model. Finally, we correlated the changes in IOP to changes in biomechanical parameters. We observed a direct correlation between the IOP measurements and the corneal thickness. The IOP was underestimated by 0.039 mm Hg per micrometer in reduction of corneal thickness. The multifactorial linear model showed a correlation of IOP change to A2 velocity and the radius of applanation. Surgical thinning of the central cornea via LASIK demonstrated a direct correlation between corneal thickness and IOP measurements using the CorVis ST technique. Postoperative changes of the A2 velocity and the applanation radius also had a statistically significant influence on post-LASIK IOP measurements. Our findings could be useful to obtain more precise post-LASIK IOP measurements.

  16. Intraocular Pressure Fluctuations and 24-Hour Continuous Monitoring for Glaucoma Risk in Wind Instrument Players.

    Science.gov (United States)

    de Crom, Ronald M P C; Webers, Carroll A B; van Kooten-Noordzij, Marina A W; Michiels, Agnes C; Schouten, Jan S A G; Berendschot, Tos T J M; Beckers, Henny J M

    2017-10-01

    The purpose of this study is to investigate the influence of playing a wind instrument on intraocular pressure (IOP) and to monitor 24-hour (IOP) fluctuations in wind musicians of symphony and wind orchestras to compare IOP levels during normal daily activities with IOP levels during playing. Professional and amateur musicians of symphony and wind orchestras were invited to participate. A total of 42 participants, 9 with glaucoma, underwent a routine ophthalmologic examination. IOP measurements were taken before and immediately after 20 minutes of playing wind instruments. In addition, 6 participants underwent 24-hour IOP monitoring with the Triggerfish (Sensimed AG, Switzerland) sensing contact lens, during which they kept an activity logbook. Eleven professionals and 31 amateur musicians participated in the study. A total of 7 eyes of 6 patients underwent additional 24-hour IOP monitoring. Mean IOP before playing was 13.6±2.6 mm Hg, IOP change after playing was +1.5±2.2 mm Hg with a significant difference between professionals (2.5±1.5 mm Hg) and amateurs (1.1±2.3 mm Hg). There were no significant differences in IOP change between subjects with or without glaucoma. During 24-hour IOP monitoring there were slight increases in IOP while playing an instrument, but also during other activities and overnight. These latter IOP levels were similar or even higher than the IOP rise caused by playing a wind instrument. IOP often rises after playing wind instruments, but similar or even higher IOP levels seem to occur during common other daily activities or at night. These peaks may be relevant for glaucomatous field progression and treatment of glaucoma patients.

  17. Twenty-four-hour intraocular pressure patterns in patients with thyroid eye disease.

    Science.gov (United States)

    Parekh, Anjali S; Mansouri, Kaweh; Weinreb, Robert N; Tafreshi, Ali; Korn, Bobby S; Kikkawa, Don O

    2015-03-01

    To prospectively investigate the safety, tolerability and 24-h intraocular pressure (IOP) patterns in patients with thyroid eye disease (TED) using a contact lens sensor (CLS). Prospective study. Ten patients with established TED. Ten eyes of 10 patients were prospectively evaluated in an ambulatory 24-h IOP monitoring session using the CLS (Sensimed AG, Lausanne, Switzerland). Patients pursued daily activities, and sleep behaviour was uncontrolled. Incidence of adverse events (AEs) and tolerability (scale of 0-10, increasing intolerance) were assessed. IOP patterns were evaluated using a cosinor rhythmometry model, and linear regression slopes were constructed for the transition from wake/sitting (W/S) to sleep/supine (S/S) and vice versa. Mean age was 61.8 ± 21.6 years, and 90% of patients were female. Main AEs were blurred vision (50%), conjunctival hyperaemia (100%) and superficial punctate keratitis (20%). Tolerability of the lens was found to be 1.5 ± 0.7. Positive linear slopes of the CLS signal from wake to sleep were detected (18.0 ± 43.8 arbitrary units [a.u.]; P = 0.254), whereas at the transition from S/S to W/S a significant decrease (-62.9 ± 56.8 a.u.; P = 0.010) was found. Five patients (50%) had a significant nocturnal/sleep acrophase with the peak occurring at 6:30 a.m. The mean amplitude of the 24-h curves was 102.2 ± 52.6 a.u. In patients with TED, the CLS provides a safe and well-tolerated approach to 24-h IOP monitoring. After modelling the 24-h IOP curves, TED patients were found to have a morning acrophase. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

  18. Corneal Biomechanical Changes After Trabeculectomy and the Impact on Intraocular Pressure Measurement.

    Science.gov (United States)

    Pillunat, Karin R; Spoerl, Eberhard; Terai, Naim; Pillunat, Lutz E

    2017-03-01

    To evaluate corneal biomechanical changes induced by trabeculectomy and their impact on intraocular pressure (IOP) measurements. In total, 35 eyes of 35 consecutive glaucoma patients undergoing first-time trabeculectomy with mitomycin C were enrolled in this prospective interventional case series. Goldmann applanation tonometry (GAT) IOP, central corneal thickness, axial length, and Ocular Response Analyzer measurements [Goldmann-correlated IOP (IOPg), corneal-compensated IOP (IOPcc), corneal hysteresis (CH), and corneal resistance factor (CRF)] were assessed before and 6 months after uncomplicated trabeculectomy. Linear mixed models were used to compare the parameters before and after surgery. IOP, central corneal thickness, and axial length showed a strong correlation with CH and CRF preoperatively and postoperatively. After adjusting for these influencing factors, CH changed from 7.75±1.46 to 7.62±1.66 mm Hg (P=0.720) and CRF from 8.67±1.18 to 8.52±1.35 mm Hg (P=0.640) after trabeculectomy, but these changes were not statistically significant. IOP decreased statistically significantly with all IOP measurements (P=0.001). IOPcc was statistically significantly higher than GAT (4.82±5.24 mm Hg; P=0.001) and IOPg (2.92±1.74 mm Hg; P=0.001) preoperatively and postoperatively (GAT, 3.29±3.36 mm Hg; P=0.001; IOPg, 3.35±1.81 mm Hg; P=0.001). The difference between IOPcc and GAT (P=0.5) and IOPcc and IOPg (P=0.06) did not change significantly before or after trabeculectomy. Despite a marked IOP reduction and a possible weakening of the ocular walls after trabeculectomy, corneal structural tissue properties are not altered, and therefore, the accuracy of IOP measurements is not changed postoperatively. It seems likely, however, that Goldmann-correlated IOP measurements are underestimated in glaucoma patients before and after surgery.

  19. Intraocular Pressure Measurements by Three Different Tonometers in Children with Aphakic Glaucoma and a Thick Cornea

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Razeghinejad

    2014-01-01

    Full Text Available Background: To evaluate the agreement in intraocular pressure (IOP measurements by Ocular Response Analyzer (ORA and Tono-Pen XL (TXL with the Goldmann Applanation Tonometer (GAT and to examine corneal biomechanical properties in aphakic glaucoma patients with a central corneal thickness (CCT >600 µ. Methods: Thirty-six eyes of aphakic glaucoma patients (group 1 and 40 eyes of normal children (group 2 were studied. The mean ORA and TXL IOP values were compared with the GAT-IOP values. Regression analyses were used to evaluate the associations between IOP and CCT, corneal hysteresis (CH, and corneal resistance factor (CRF. Bland-Altman plots were used to evaluate the agreement between the tonometers. Results: The mean±standard deviations of the age and male/female ratio were 16.58±5.44 and 15.75±5.04 years and 14/22 and 18/22 in group 1 and group 2, respectively. CCT in group 1 was 651.1±42 and in group 2 was 567.3±32.4. In group 1, the mean TXL (22.4, P=0.004, IOPcc (corneal compensated (27.8, P=0.005, and IOPg (Goldmann correlated values (28.1, P<0.0001 were greater than GAT-IOP (20.6. In group 2, only IOPg value (16.4 was higher than GAT-IOP (14.8, P=0.04. IOP reading of all the tonometers were positively and negatively associated with CRF and CH in the multiple regression analysis, respectively. Conclusion: The TXL had a greater agreement with the GAT, and the ORA overestimated IOP in aphakic glaucoma patients. The ORA and TXL seemed to be affected by CH and CRF.

  20. [Intraocular pressure, ocular blood flow, and corneal biomechanics changes after LASIK surgery for myopia].

    Science.gov (United States)

    Avetisov, S E; Mamikonyan, V R; Shmeleva-Demir, O A; Karamyan, A A; Bubnova, I A; Kazaryan, E E; Galoyan, N S; Karapetyan, A T

    2016-01-01

    to study changes in intraocular pressure (IOP), volumetric ocular blood flow (OBF) rate, and biomechanical properties of the cornea after excimer laser ablation in patients with myopia of different degrees. A total of 16 patients (32 eyes) with myopia ranging from 2.75 to 9.0 D were examined before and after LASIK. Ocular Blood Flow Analyzer (OBFA) was used to measure IOP and OBF as well as pulse amplitude and volume. Ocular Response Analyzer (ORA) was also employed to provide the following data: Goldmann-equivalent IOP, corneal compensated IOP, corneal hysteresis, and corneal resistance factor. The eyes were then divided into two groups: group 1 - 15 eyes with less than 70-µm deep ablation of the cornea and group 2 - 17 eyes with more than 70-µm deep ablation. Group 1 demonstrated a statistically reliable decrease in IOP values provided by either method and biomechanical parameters of the cornea (p0.05). In group 2, all the parameters changed reliably, except for the pulse volume (p>0.05). In particular, a decrease was recorded for IOP (with no dependence to the method of measurement; pcorneal hysteresis (pcorneal resistance factor (p<0.001); an increase - for OBF (p<0.05). One should allow for possible mismeasurement of IOP and OBF as well as biomechanical parameters of the cornea in post-LASIK patients, keeping in mind that the extent of error depends on the depth of ablation. Shallow ablation (no more than 70-µm deep) has no statistically significant effect on OBF readings, while IOP seems to decrease considerably. In deep ablation (more than 70-µm deep), both parameters are reliably lower than at baseline.

  1. Intraocular pressure measurement by three different tonometers in primary congenital glaucoma

    Directory of Open Access Journals (Sweden)

    Athar Zareei

    2015-01-01

    Full Text Available Purpose: To determine the agreement between intraocular pressure (IOP measurements using an automated non-contact tonometer (NCT, Goldmann applanation tonometer (GAT, and the ocular response analyzer (ORA in subjects with primary congenital glaucoma (PCG. Methods: Twenty-nine eyes of 17 PCG patients underwent IOP measurements using NCT, GAT and ORA. Variables obtained by the ORA were corneal-compensated IOP (IOPcc, Goldmann-correlated IOP (IOPg, corneal hysteresis (CH, and corneal resistance factor (CRF. A difference more than 1.5 mmHg for IOP was considered as clinically relevant. Results: Mean age of the patients was 12 years. Mean IOP (±standard deviation, SD was 15.3 ± 2.8 mmHg (GAT, 15.5 ± 6.0 (NCT, 19.2 ± 7.0 (IOPg, and 21.1 ± 7.9 (IOPcc; (P = 0.001. Except for NCT vs. GAT (P = 1.0, the average IOP difference between each pair of measurements was clinically relevant. The 95% limits of agreements were − 10.2 to 10.3 mmHg (NCT vs. GAT, −7.8 to 15.3 (IOPg vs. GAT, and − 8.1 to 19.0 (IOPcc vs. GAT. The differences in IOP measurements increased significantly with higher average IOP values (r = 0.715, P = 0.001, for NCT vs. GAT; r = 0.802, P < 0.001, for IOPg vs. GAT; and r = 0.806, P < 0.001, for IOPcc vs. GAT. CH showed a significant association with differences in IOP measurements only for IOPcc vs. GAT (r = 0.830, P < 0.001. Conclusion: Mean IOP obtained by NCT was not significantly different from that of GAT, but ORA measured IOPs were significantly higher than both other devices.

  2. Combining corneal hysteresis with central corneal thickness and intraocular pressure for glaucoma risk assessment.

    Science.gov (United States)

    Pensyl, D; Sullivan-Mee, M; Torres-Monte, M; Halverson, K; Qualls, C

    2012-10-01

    To determine whether adjusting corneal hysteresis (CH) values for central corneal thickness (CCT) and intraocular pressure (IOP) improves its capability to differentiate primary open-angle glaucoma (POAG) from ocular hypertension (OH). This prospective, observational, cross-sectional study included 169 eyes of 169 subjects with a diagnosis of POAG (n=81) or OH (n=88). We utilized the Ocular Response Analyzer (ORA), Pascal Dynamic Contour Tonometer (DCT), Goldmann applanation tonometer (GAT), and ORA ultrasound pachymeter to obtain CH, IOP, and CCT values. Correlational, regression, and t-test analyses were conducted before and after the sample was divided into low, intermediate, and thick CCT subgroups. In the full sample, CH and CCT were moderately correlated (r=0.44, P<0.001). Although both were related to diagnosis in univariate regression analysis, only CH was independently related to glaucoma diagnosis in multivariate analysis. After the sample was divided into CCT tertiles, CH was significantly lower in POAG vs OH eyes within all three CCT subgroups, and CH was the only multivariate variable that differentiated POAG from OH in each CCT subgroup. Moreover, the relationship between CH and diagnosis was more robust within the CCT subgroups compared with the full sample, suggesting that integrating CCT into CH interpretation is beneficial. Adjusting CH for IOP did not aid diagnostic precision in this study. Our findings suggest that combining CH and CCT for glaucoma risk assessment improves diagnostic capability compared to using either factor alone. Conversely, adjusting CH for IOP provided no clear clinical benefit in this study.

  3. Retrospective analysis of surgical treatment of closed-angle glaucoma with persistent high intraocular pressure

    Directory of Open Access Journals (Sweden)

    Zhi-Jie Chen

    2015-12-01

    Full Text Available AIM:To observe the safety and clinical curative effect of trabeculectomy on continuous high intraocular pressure(IOPin primary angle-closure glaucoma. METHODS:From January 2013 to January 2015, 45 patients(46 eyeswith high IOP in primary angle-closure glaucoma were treated in the department of ophthalmology in our hospital. The age of patients was(56.9±9.4years old, ranged from 43~81 years. All the patients underwent the examinations of visual acuity, best corrected visual acuity(BCVA, slit lamp, fundus IOP, perimetry and ultrasound B scan. Under local anesthesia, the patients underwent anterior chamber paracentesis, postoperative they received topical acetate prednisolone eye drops and tobramycin and dexamethasone eye ointment, combining with IOP lowering eye drops and glycerol fructose injection intravenous to further control IOP. Two days after surgery, the patients received trabeculectomy with amniotic membrane implantation and intracameral gas injection(some cases underwent pars plana puncture. Visual acuity, BCVA, IOP, slit lamp, fundus were observed postoperative and complications occurred during the operation were recorded.RESULTS:The average IOP at 1 and 2d after anterior chamber puncture were 21.4±5.2, 20.3±4.8mmHg(1kPa=7.5mmHg, which was significantly lower than that before surgery(F=492.601, PF=857.508, Pt=10.191, 10.950, 9.523, PPCONCLUSION:For acute primary angle closure glaucoma with persistent high IOP, anterior chamber puncture and intracameral gas injection combined with trabeculectomy is a safe and effective method, which can reduce intraoperative and postoperative complications and improve the visual acuity of most patients.

  4. Intraocular pressure measurement by three different tonometers in primary congenital glaucoma.

    Science.gov (United States)

    Zareei, Athar; Razeghinejad, Mohammad Reza; Nowroozzadeh, Mohammad Hosein; Mehrabi, Yadollah; Aghazadeh-Amiri, Mohammad

    2015-01-01

    To determine the agreement between intraocular pressure (IOP) measurements using an automated non-contact tonometer (NCT), Goldmann applanation tonometer (GAT), and the ocular response analyzer (ORA) in subjects with primary congenital glaucoma (PCG). Twenty-nine eyes of 17 PCG patients underwent IOP measurements using NCT, GAT and ORA. Variables obtained by the ORA were corneal-compensated IOP (IOPcc), Goldmann-correlated IOP (IOPg), corneal hysteresis (CH), and corneal resistance factor (CRF). A difference more than 1.5 mmHg for IOP was considered as clinically relevant. Mean age of the patients was 12 years. Mean IOP (±standard deviation, SD) was 15.3 ± 2.8 mmHg (GAT), 15.5 ± 6.0 (NCT), 19.2 ± 7.0 (IOPg), and 21.1 ± 7.9 (IOPcc); (P = 0.001). Except for NCT vs. GAT (P = 1.0), the average IOP difference between each pair of measurements was clinically relevant. The 95% limits of agreements were - 10.2 to 10.3 mmHg (NCT vs. GAT), -7.8 to 15.3 (IOPg vs. GAT), and - 8.1 to 19.0 (IOPcc vs. GAT). The differences in IOP measurements increased significantly with higher average IOP values (r = 0.715, P = 0.001, for NCT vs. GAT; r = 0.802, P IOP measurements only for IOPcc vs. GAT (r = 0.830, P IOP obtained by NCT was not significantly different from that of GAT, but ORA measured IOPs were significantly higher than both other devices.

  5. [Comparison of measurement of intraocular pressure by ICARE PRO® tonometer and Goldman applanation tonometer].

    Science.gov (United States)

    Hladíková, E; Pluháček, F; Marešová, K

    2014-06-01

    The paper compares a concordance in measuring the intraocular pressure (IOP) using two different tonometers, Goldman applanation tonometer (GAT) and ICARE PRO® tonometer. GAT is nowadays considered a standard device for measuring the IOP at the offices of ophthalmologists. Options of the measurements are however limited by necessary installation as well as use of a slit lamp where the evaluation is made subjectively by the examiner. The ICARE PRO® tonometer is a light and mobile device that allows to perform the measurement horizontally as well as vertically. The results are calculated automatically. The data for the paper was collected by IOP measurements in right and left eye in 45 individuals at the age range of 8-84 years. They were all diagnosed for glaucoma or were suspected to have glaucoma. The measurements were carried out always at the same day time. The acquired data was compared by a double select paired t-test with a significance level p = 0.05 and then analyzed by Bland-Altman method. There was no statistically important difference (p > 0.26) between the two devices. The average IOP measured by the ICARE PRO® tonometer was 18.19 mm Hg with standard deviation 3.70 mm Hg, whereas the average IOP measured by GAT was 17.94 mm Hg with standard deviation 3.66 mm Hg. It was observed that the difference in the measurements was not related to the IOP. The results show an acceptable concordance of measurements performed by the two devices. The ICARE PRO® tonometer, in comparison with its predecessor ICARE® TA01 evaluated in the past, shows a much smaller average difference in collected values compared with GAT. Based on the analysis of the collected data it may be stated that measuring the IOP by ICARE PRO® tonometer is clinically acceptable alternative to the use of GAT.

  6. Intraocular pressure and photorefractive keratectomy: a comparison of three different tonometers.

    Science.gov (United States)

    Garzozi, H J; Chung, H S; Lang, Y; Kagemann, L; Harris, A

    2001-01-01

    To evaluate the intraocular pressure (IOP) with three different instruments, Goldmann applanation tonometer (GAT), noncontact tonometer, and Tono-Pen after photorefractive keratectomy (PRK) for myopia. A prospective case series study to evaluate preoperative and postoperative IOP measurements of 149 eyes at 12 months. We performed GAT, noncontact tonometry, Tono-Pen central, and Tono-Pen temporal periphery measurements. We also performed measurements of the central corneal thickness (CCT) by ultrasonic pachymetry and keratometry. Pre-operative IOP reading served as control for all studies. After PRK, IOP reading was significantly reduced in the treated eyes when compared with the control measurements (11.87+/-1.73 vs. 13.37+/-1.52 mm Hg, pPen central; 13.48+/-1.65 vs. 13.71+/-1.56 Hg, pPen temporal periphery). There was also a significant correlation between IOP reading changes measured by GAT, noncontact tonometer, Tono-Pen central, and change of CCT and between reduction of IOP reading and keratometry (r2>0.39, pIOP reading change by Tono-Pen temporal periphery and CCT was also significant but r2 value was only 0.034. Tono-Pen temporal periphery postoperative IOP measurements had the best correlation with preoperative GAT IOP (r2 = 0.57, pIOP reading as measured by GAT, noncontact tonometer, and Tono-Pen central; less so when measured by Tono-Pen temporal periphery. Early detection of glaucoma and IOP follow-up in glaucoma patients may be done best by peripheral Tono-Pen measurements over the nonablated cornea.

  7. The effect of orbital decompression surgery on refraction and intraocular pressure in patients with thyroid orbitopathy.

    Science.gov (United States)

    Norris, J H; Ross, J J; Kazim, M; Selva, D; Malhotra, R

    2012-04-01

    To investigate the effect of orbital decompression surgery in thyroid orbitopathy (TO) on both refractive status and intraocular pressure (IOP). A prospective, multicentre, consecutive audit of patients undergoing thyroid decompression surgery. Indications for surgery included cosmetically unacceptable proptosis or corneal exposure. Exclusion criteria included the following: previous orbital surgery, glaucoma, corneal disease, steroid use in the preceding 12 months, or an acute optic neuropathy. Automated refraction, keratometry, pachymetry, Hertel exophthalmometry, and IOP were recorded at 1 month pre- and 3 months postoperatively. IOP using the Tono-Pen (mean of three readings) was measured in the primary, upgaze, and downgaze positions. Data were collected from 52 orbits of 33 patients (East Grinstead, New York, and Adelaide). There was no significant difference between pre- and postoperative data for sphere, cylinder, or central corneal thickness (CCT). The mean spherical equivalent was -0.43 ± 1.49 D pre-operatively and -0.28 ± 1.52 D postoperatively. The steepest meridian of corneal curvature was 93.1 degrees pre- and 94.2 degrees postoperatively, with no significant difference. Mean IOP significantly decreased when measuring by Goldmann applanation tonometry (GAT) (2.28 mm Hg, (*) P=0.001) and Tono-Pen (3.06 mm Hg, (*) P=IOP measured in upgaze was significantly greater than that in the primary position. Regression analysis between change in IOP and either Hertel exophthalmometry or the number of orbital walls decompressed was non-significant ((*)Student's t-test). Patients with TO undergoing orbital decompression had, on average, with-the-rule astigmatism not affected by orbital decompression surgery. IOP was significantly reduced by decompression surgery although no relationship between IOP and the degree of decompression was observed.

  8. Not only pregnancy but also the number of fetuses in the uterus affects intraocular pressure

    Directory of Open Access Journals (Sweden)

    Metin Saylik

    2014-01-01

    Full Text Available Aim: To investigate whether, intraocular pressure (IOP is affected when there is a second fetus in the uterus during pregnancy. Materials and Methods: Eighty eyes of 40 twin pregnancies (TwPs, 80 eyes of 40 singleton pregnancies (SiPs and 80 eyes of 40 non-pregnant females (NoPs were included in the study. Statistical Analysis: Repeated measurements analysis of variance with two factors, one-way analysis of variance (ANOVA and theTukey′s multiple comparison test were used. Results: The mean IOP (MIOP values in TwPs were 14.29 ± 1.28, 11.48 ± 1.20, and 9.81 ± 1.36 mmHg and the MIOP values in SiPs were 14.42 ± 0.95, 13.12 ± 0.75, and 10.97 ± 0.89 mmHg in subsequent trimesters. The MIOP values in NoPs were 14.77 ± 1.18, 14.92 ± 1.33, and 15.08 ± 0.89 mmHg in subsequent 3-month measurements. The results show that the MIOP values for the TwPs group were significantly lower than the SiPs in all trimesters. Conclusions: During pregnancy, the number of fetuses in the uterus is an indirectly important factor that influences the decrease in IOP. We hypothesize that the increased ocular hypotensive effect of TwPs is most likely related to the presence of higher levels of hormones, particularly estrogen, progesterone and relaxin compared with SiPs.

  9. Transiently raised intraocular pressure reveals pattern electroretinogram losses in ocular hypertension.

    Science.gov (United States)

    Colotto, A; Falsini, B; Salgarello, T; Buzzonetti, L; Cermola, S; Porrello, G

    1996-12-01

    It is known that the pattern electroretinogram (PERG) of normal subjects is reduced temporarily after short-term elevation of intraocular pressure (IOP). The authors evaluated PERG changes in ocular hypertension during and after transient IOP elevation. Steady state (8 Hz) PERGs to sinusoidal gratings (1.7 cyc/deg spatial frequency) were recorded in seven untreated patients with ocular hypertension at medium risk (maximum IOP, 22 to 25 mm Hg; cup-disk ratio, 0.6 to 0.7; normal Humphrey 30-2 visual field results; positive family history), as well as in six age-matched normal subjects. Recordings were obtained for the baseline condition during a short-term (6-minute) IOP elevation (to 30 mm Hg) by using a suction cup apparatus and during a 6-minute recovery period after removal of the apparatus. During IOP elevation, PERG amplitudes were reduced significantly from baseline values in normal subjects and patients. However, PERG losses were significantly greater in patients (average loss from baseline after 4 minutes of IOP elevation: 72% +/- 7.6%) compared to controls (average loss after 2 minutes of IOP elevation: 40% +/- 7.5%). In the recovery phase, mean PERG amplitude returned to baseline values in normal subjects but not in patients, whose recovery took longer. In normal subjects, PERG phase did not change either during or after IOP elevation. In patients, however, PERG phase showed a delay from baseline during and after IOP elevation (average delay after 6 minutes of recovery: -41.1 degrees +/- 13 degrees). Results indicate that increasing IOP with scleral suction produces greater PERG losses in eyes with ocular hypertension than in normal eyes. This suggests that the inner retina of eyes with ocular hypertension may have a heightened sensitivity to vascular or mechanical changes induced by transient IOP elevation.

  10. Central corneal thickness and intraocular pressure in captive black-footed penguins (Spheniscus dermersus).

    Science.gov (United States)

    Gonzalez-Alonso-Alegre, Elisa M; Martinez-Nevado, Eva; Caro-Vadillo, Alicia; Rodriguez-Alvaro, Alfonso

    2015-01-01

    To determine the central corneal thickness (CCT) by ultrasonic pachymetry and the effect of these values on the measurements of intraocular pressures (IOP) with rebound tonometry (TonoVet(®) ) in a captive flock of black-footed penguins (Spheniscus dermersus). Variations in CCT by age and weight, and variations in IOP by age were compared. Both eyes of 18 clinically normal black-footed penguins (Spheniscus dermersus) were used. The IOP was measured by the TonoVet(®) in both eyes of all the penguins. CTT measurements were performed 5 min later in all eyes using an ultrasound pachymeter. The mean IOP values ± SD were 31.77 ± 3.3 mm Hg (range of mean value: 24-38). The mean CCT values were 384.08 ± 30.9 μm (range of mean value: 319-454). There was no correlation between IOP and CCT values (P = 0.125). There was no difference in CCT measurements by age (P = 0.122) or weight (P = 0.779). A correlation was observed (P = 0.032) between IOP values and age. The coefficient of correlation was negative (ρ = -0.207). Ultrasound pachymetry has shown to be a reliable and easy technique to measure CCT in penguins. No correlation was observed between IOP and CCT values in this study. IOP showed a significant but weak decrease as age increased in the black-footed penguin. © 2014 American College of Veterinary Ophthalmologists.

  11. Comparison of intraocular pressure fluctuations before and after ab interno trabeculectomy in pseudoexfoliation glaucoma patients.

    Science.gov (United States)

    Tojo, Naoki; Abe, Shinya; Miyakoshi, Mari; Hayashi, Atsushi

    2017-01-01

    Ab interno trabeculectomy (AIT) with the Trabectome has been shown to reduce intraocular pressure (IOP) in eyes with pseudoexfoliation (PEX) glaucoma. Here, we examined the change of IOP fluctuations before and after only AIT or AIT with cataract surgery in PEX patients using the contact lens sensor Triggerfish(®). This was a prospective open-label study. Twenty-four consecutive patients with PEX glaucoma were included. Twelve patients underwent cataract surgery and AIT (triple-surgery group), and 12 patients underwent only AIT (single-surgery group). In each eye, IOP fluctuations over 24 h were measured with the contact lens sensor before and at 3 months after the surgery. We compared the change of IOP fluctuation before and after operation. We also evaluated the difference in IOP changes between the triple- and single-surgery groups. At 3 months after the surgeries, the mean IOP was significantly reduced from 23.5±6.5 mmHg to 14.6±2.8 mmHg in the single-surgery group and from 22.5±3.0 mmHg to 11.5±2.9 mmHg in the triple-surgery group. The mean IOP reduction rate was significantly higher in the triple-surgery group compared to the single-surgery group (p=0.0358). In both groups, the mean range of IOP fluctuations was significantly decreased during nocturnal periods. The mean range of 24 h IOP fluctuations was decreased in the triple-surgery group (p=0.00425), not in the single-surgery group (p=0.970). Triple surgery could decrease IOP value and the IOP fluctuations to a greater extent than single surgery in PEX glaucoma patients.

  12. Diurnal variation in central corneal thickness and intraocular pressure in eyes with pseudoexfoliation syndrome without glaucoma

    Science.gov (United States)

    Keel, Stuart; Malesic, Linda; Chan, Siew-Pang

    2014-01-01

    Aim: The aim was to ascertain if any differences exist in diurnal central corneal thickness (CCT) and intra-ocular pressure (IOP) between eyes with pseudoexfoliation (PXF) syndrome without glaucoma and eyes with no ocular pathology. A secondary aim was to determine whether there was a significant relationship between CCT and IOP. Settings and Design: This study was a prospective design conducted within a hospital setting. Materials and Methods: The experimental group consisted of seven participants with bilateral PXF (14 eyes) and the control group comprised of 15 participants (30 eyes). Testing included CCT and IOP measured at four different times on one given day (8.00 a.m.; 11 a.m.; 2 p.m. and 5 p.m.). Statistical Analysis: The data were analyzed with the generalized linear latent mixed model. Results: PXF eyes displayed a significantly thinner overall mean CCT (520 μm) compared to controls (530 μm). Furthermore, a significant reduction in CCT and IOP occurred in the PXF group from 8 a.m. to 5 p.m. The mean overall IOP in PXF eyes was significantly lower than the control group. A significant association between IOP and CCT was also found in PXF eyes. Conclusions: Displaying a significantly thinner mean CCT highlights the importance of measuring CCT in an ophthalmic clinical setting as to avoid falsely underestimated IOP measurements in such a high-risk glaucoma population. Furthermore, a statistically significant correlation between IOP and CCT in PXF eyes suggests that the reduction in CCT that occurred in PXF eyes between 8 a.m. and 5 p.m. may be partly responsible for the reduction in IOP measurements. PMID:25494249

  13. The Risk of Intraocular Pressure Elevation in Pediatric Non-infectious Uveitis

    Science.gov (United States)

    Kothari, Srishti; Foster, C. Stephen; Pistilli, Maxwell; Liesegang, Teresa L.; Daniel, Ebenezer; Sen, H. Nida; Suhler, Eric B.; Thorne, Jennifer E.; Jabs, Douglas A.; Levy-Clarke, Grace A.; Nussenblatt, Robert B.; Rosenbaum, James T.; Lawrence, Scott D.; Kempen, John H.

    2015-01-01

    Purpose To characterize the risk and risk factors for intraocular pressure (IOP) elevation in pediatric non-infectious uveitis. Design Multi-center retrospective cohort study. Participants Nine hundred sixteen children (1593 eyes) uveitis followed between January 1978 through December 2007 at five academic uveitis centers in United States. Methods Medical records review by trained, certified experts. Main outcome measures Prevalence and incidence of IOP≥21 and ≥30mmHg and incidence of a rise in IOP by ≥10mmHg. To avoid under ascertainment, outcomes were counted as present when IOP-lowering therapies were in use. Results Initially 251 (15.8%) and 46 eyes (2.9%) had IOP≥21 and ≥30mmHg, respectively. Factors associated with presenting IOP elevation included age 6–12 years (versus other pediatric ages), prior cataract surgery (adjusted odds ratio≥21mmHg [aOR21]=2.42, P=0.01), pars plana vitrectomy (adjusted odds ratio≥30mmHg[aOR30]=11.1, P=0.03), duration of uveitis ≥6 months (aORs30 up to 11.8, Puveitis. Statistically significant risk factors include IOP elevation or use of IOP-lowering treatment in the contralateral eye and local corticosteroid use – that demonstrated a dose-and route of administration-dependent relationship. In contrast, use of immunosuppressive drug therapy did not increase such risk. Pediatric eyes with non-infectious uveitis should be followed closely for IOP elevation when strong risk factors such as the use of local corticosteroids and contralateral IOP elevation are present. PMID:26233626

  14. Safety and efficacy of travoprost solution for the treatment of elevated intraocular pressure

    Directory of Open Access Journals (Sweden)

    Quaranta L

    2015-04-01

    Full Text Available Luciano Quaranta,1,* Ivano Riva,1,* Andreas Katsanos,2 Irene Floriani,3 Marco Centofanti,4,† Anastasios G P Konstas51Centre for the Study of Glaucoma, University of Brescia, Brescia, Italy; 2Ophthalmology Department, University of Ioannina, Ioannina, Greece; 3Laboratory of Clinical Research, IRCCS, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy; 4DSCMT, University of Tor Vergata, Rome, Italy; 5Glaucoma Unit, 1st University Department of Ophthalmology, AHEPA Hospital, Thessaloniki, Greece*These authors contributed equally to this work; †Dr Centofanti passed away on 1 March 2015Abstract: Travoprost is a prostaglandin analogue widely used for reducing intraocular pressure (IOP in patients affected with glaucoma and ocular hypertension. It exerts its ocular hypotensive effect through the prostaglandin FP receptors, located in the ciliary muscle and the trabecular meshwork. Several studies have shown that topical administration of travoprost induces a mean IOP reduction ranging from 25% to 32%, and sustained throughout the 24-hour cycle. When compared with timolol, travoprost is more effective at reducing IOP, while generally no difference has been found in the head-to-head comparison with other prostaglandin analogues. The fixed combination of travoprost and timolol has demonstrated a hypotensive efficacy comparable to the concomitant administration of the two drugs. Recently, a new preservative-free formulation of travoprost 0.004% has been marketed for reducing tolerability-related problems in subjects affected with ocular surface disease. Low rates of topical and systemic adverse reactions, strong ocular hypotensive efficacy, and once-a-day dosing make travoprost a first-line treatment for patients affected with elevated IOP.Keywords: prostaglandin analogue, glaucoma, ocular hypertension

  15. Glaucoma and intraocular pressure in EPIC-Norfolk Eye Study: cross sectional study

    Science.gov (United States)

    Chan, Michelle P Y; Broadway, David C; Khawaja, Anthony P; Yip, Jennifer L Y; Garway-Heath, David F; Burr, Jennifer M; Luben, Robert; Hayat, Shabina; Dalzell, Nichola; Khaw, Kay-Tee

    2017-01-01

    Objectives To report the distribution of intraocular pressure (IOP) by age and sex and the prevalence of glaucoma. Design Community based cross sectional observational study. Setting EPIC-Norfolk cohort in Norwich and the surrounding rural and urban areas. Participants 8623 participants aged 48-92 recruited from the community who underwent ocular examination to identify glaucoma. Main outcome measures Prevalence and characteristics of glaucoma, distribution of IOP, and the sensitivity and specificity of IOP for case finding for glaucoma. Results The mean IOP in 8401 participants was 16.3 mm Hg (95% confidence interval 16.2 mm Hg to 16.3 mm Hg; SD 3.6 mm Hg). In 363 participants (4%), glaucoma was present in either eye; 314 (87%) had primary open angle glaucoma. In the remaining participants, glaucoma was suspected in 607 (7%), and 863 (10.0%) had ocular hypertension. Two thirds (242) of those with glaucoma had previously already received the diagnosis. In 76% of patients with newly diagnosed primary open angle glaucoma (83/107), the mean IOP was under the threshold for ocular hypertension (21 mm Hg). No one IOP threshold provided adequately high sensitivity and specificity for diagnosis of glaucoma. Conclusions In this British community, cases of glaucoma, suspected glaucoma, and ocular hypertension represent a large number of potential referrals to the hospital eye service. The use of IOP for detection of those with glaucoma is inaccurate and probably not viable. PMID:28903935

  16. Intraocular pressure measurements and biomechanical properties of the cornea in eyes after penetrating keratoplasty.

    Science.gov (United States)

    Fabian, Ido D; Barequet, Irina S; Skaat, Alon; Rechtman, Ehud; Goldenfeld, Mordechai; Roberts, Cynthia J; Melamed, Shlomo

    2011-05-01

    To compare intraocular pressure (IOP) measurements obtained using the Goldmann applanation tonometer (GAT; Haag-Streit), the Tono-Pen XL (Reichert, Inc), and the ocular response analyzer (ORA; Reichert Ophthalmic Instruments), and to determine the influence of corneal factors on IOP measurements in eyes that had undergone penetrating keratoplasty (PK). Consecutive, prospective study. Study population. Sixty-one eyes that underwent PK were enrolled in this study. Intervention. IOP was measured using the GAT, Tono-Pen, and ORA. Corneal hysteresis and corneal resistance factor as provided by the ORA were recorded. Central corneal thickness was measured using an ultrasound pachymeter. Main outcome measures. IOP and corneal biomechanical factors. IOP measurements were obtained in an average of 65 months (range, 6 to 209 months) after PK surgery. ORA-derived IOP measurements (corneal-compensated IOP and Goldmann-correlated IOP) and Tono-Pen XL IOP all correlated in a significant manner to GAT IOP measurements. Corneal-compensated IOP and Tono-Pen XL IOP values were higher than GAT IOP (P < .001 and P = .001, respectively), whereas Goldmann-correlated IOP readings did not differ from GAT IOP readings (P = .054). Central corneal thickness did not correlate to any tonometry technique. In a regression analysis, corneal hysteresis and corneal resistance factor were found to play a role in IOP prediction. Central corneal thickness may be of less importance than corneal hysteresis and corneal resistance factor in IOP determination in eyes that have undergone PK, perhaps because of the lower modulus of elasticity in these eyes. GAT IOP seems to be lower than other tonometry techniques in eyes that have undergone PK. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. The Association of Intraocular Pressure with Vitamin D Levels and Bone Mineral Density in Postmenopausal Osteoporosis

    Directory of Open Access Journals (Sweden)

    Mehmet Uçar

    2015-04-01

    Full Text Available Objective: To investigate the effects of osteoporosis (OP and vitamin D level on intraocular pressure (IOP and to determine whether those constitute a risk factor for glaucoma. Materials and Methods: Eighty postmenopausal patients with the diagnosis of OP (group 1 and 74 controls (group 2 were included in the study. Age, height, weight and body mass index (BMI of the patients were recorded. Bone mineral density (BMD was measured from the lumbar vertebrae and proximal femur by using dual-energy x-ray absorptiometry (Lunar DPX-IQ®. The levels of 25(OH-vitamin D were measured. Visual acuity was assessed by using Snellen charts. Gonioscopy was performed following the examination of the anterior segment with biomicroscopy. Applanation tonometry was used to measure the IOP at the same daytime. Dilated fundus examination was performed after applying 1% tropicamide eye drops. Results: The mean age of the patients in group 1 and 2 were 62.4±10.5 and 60.6±11.9 years, respectively. Although the IOPs were higher in the group 1, the results were not statistically different (p>0.05. The difference between the levels of vitamin D were not statistically significant (p>0.05. There was a strong negative correlation between IOP and vitamin D (p=0.003, r=0.428. No correlations were found between BMD, lumbar vertebral and femoral T-scores and IOP (p>0.05Conclusions: The results of this study suggest that OP does not affect the IOP, but deficiency of vitamin D may be a risk factor for higher IOPs. Thus, it can be recommended that vitamin D supplement may be useful in decreasing the higher IOP which is an important risk factor for glaucoma. In the prevention of osteoporotic fractures related to falls routine ocular examination and measurement of IOP should be performed. (Turkish Journal of Osteoporosis 2015;21: 1-4

  18. Effects of topical 0.5% tropicamide on intraocular pressure in normal cats.

    Science.gov (United States)

    Stadtbäumer, Katrin; Köstlin, Roberto G; Zahn, Klaus J

    2002-06-01

    The objective of the study was to determine the effect of topical 0.5% tropicamide on intraocular pressure (IOP) in normotensive feline eyes. IOP was measured bilaterally in 70 clinically healthy cats and gonioscopy (and goniophotography) was performed. Thereafter, 50 cats were treated unilaterally with one drop of 0.5% tropicamide. The contralateral, left eye served as a control. In the placebo group consisting of 20 cats, one drop of physiologic saline solution was administered to the right eye. In all cats, IOP of both eyes was measured 30, 60 and 90 min after topical administration. After unilateral tropicamide application, IOP increased significantly both in the right and in the left eye. Maximum average IOP increase was observed at the control measurement performed 90 min after treatment, with an elevation of 3.8 +/- 4.2 mmHg in the right eye and 3.5 +/- 3.6 mmHg in the left eye. Maximum IOP increase after treatment was 18.0 mmHg in the treated eye and 17.0 mmHg in the left eye. Measurements made at 60 min after treatment revealed a significantly higher increase in IOP in the right eye as compared to the left eye (P60 tropicamide-induced mydriasis was observed in the treated eye, the contralateral eye did not show any changes in pupillary function at any time. With increasing age of the cats, IOP increase was found to be more moderate, whereas the gender of the cats did not have any significant influence on IOP changes. In the 20 cats in the placebo group, no significant changes in IOP were observed. We conclude that topical 0.5% tropicamide causes a significant elevation of IOP in the treated and untreated eye in normal cats.

  19. Assessment of Corneal Biomechanical Properties and Intraocular Pressure in Myopic Spanish Healthy Population

    Directory of Open Access Journals (Sweden)

    María A. del Buey

    2014-01-01

    Full Text Available Purpose. To examine biomechanical parameters of the cornea in myopic eyes and their relationship with the degree of myopia in a western healthy population. Methods. Corneal hysteresis (CH, corneal resistance factor (CRF, Goldmann correlated intraocular pressure (IOP, and corneal compensated IOP (IOPcc were measured using the ocular response analyzer (ORA in 312 eyes of 177 Spanish subjects aged between 20 and 56 years. Refraction was expressed as spherical equivalent (SE, which ranged from 0 to −16.50 diopters (D (mean: −3.88±2.90 D. Subjects were divided into four groups according to their refractive status: group 1 or control group: emmetropia (-0.50≤SE0.05; nevertheless, IOPcc was significantly higher in the moderately myopic (15.47±2.47 mmHg and highly myopic (16.14±2.59 mmHg groups than in the emmetropia (15.15±2.06 mmHg and low myopia groups (14.53±2.37 mmHg. No correlation between age and the measured parameters was found. CH and IOPcc were weakly but significantly correlated with SE (r=0.171, P=0.002 and r=-0.131, P=0.021, resp.. Conclusions. Present study showed only a very weak, but significant, correlation between CH and refractive error, with CH being lower in both moderately and highly myopic eyes than that in the emmetropic and low myopic eyes. These changes in biomechanical properties of the cornea may have an impact on IOP measurement, increasing the risk of glaucoma.

  20. Changes in intraocular pressure and anterior segment morphometry after uneventful phacoemulsification cataract surgery.

    LENUS (Irish Health Repository)

    Dooley, I

    2012-02-01

    PURPOSE: To study changes in anterior segment morphometry after uneventful phacoemulsification cataract surgery, and to investigate whether there is a relationship between any observed changes and intraocular pressure (IOP) reduction after the procedure. METHODS: The anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), central corneal thickness (CCT), and IOP were measured in 101 non-glaucomatous eyes before and after uneventful phacoemulsification cataract surgery. RESULTS: After cataract surgery, the mean ACD, ACV, and ACA values increased by 1.08 mm, 54.4 mm(3), and 13.1 degrees , respectively, and the mean IOP (corrected for CCT) decreased by 3.2 mm Hg. The predictive value of a previously described index (preoperative ACD\\/preoperative IOP (corrected for CCT) or CPD ratio) for IOP (corrected for CCT) reduction after cataract surgery was confirmed, reflected in an r(2) value of 23.3% between these two parameters (P<0.001). Other indices predictive of IOP reduction after cataract surgery were also identified, including preoperative IOP\\/preoperative ACV and preoperative IOP\\/preoperative ACA, reflected in r(2) values of 13.7 and 13.7%, respectively (P<0.001 and P<0.001, respectively). CONCLUSIONS: Our study confirms the predictive value of the CPD ratio for IOP reduction after cataract surgery, and may contribute to the decision-making process in patients with glaucoma or ocular hypertension. Furthermore, two novel indices of preoperative parameters that are predictive for IOP reduction after cataract surgery were identified, and enhance our understanding of the mechanisms underlying IOP changes after this procedure.

  1. Rebound tonometry versus Goldmann tonometry in school children: feasibility and agreement of intraocular pressure measurements

    Directory of Open Access Journals (Sweden)

    Bruno Leonardo Barranco Esporcatte

    2015-12-01

    Full Text Available ABSTRACT Purpose: High intraocular pressure (IOP is an important risk factor for a variety of pediatric ophthalmic conditions. The purpose of this study is to evaluate the feasibility, length of examination, and corneal epithelial damage induced by rebound tonometry (RBT versus Goldmann applanation tonometry (GAT in school children. Methods: Healthy children (n=57 participated in a randomized, transversal study with IOP measurement by GAT followed by RBT (study arm 1 or RBT followed by GAT (study arm 2. The number of attempts to acquire a reliable IOP measurement and the length of the examination were quantified. Corneal epithelial damage induced by tonometry was evaluated. Bland-Altman analysis was performed to establish the level of agreement between the two techniques. Results: The IOP was measured in all children with at least one of the devices. In both study arms, more children failed to be examined with GAT than with RBT (26% vs. 4%, and 16% vs. 6%, p<0.001, in study arm 1 and 2, respectively. The length of examination was shorter for RBT than for GAT (67.81 s ± 35.20 s vs. 126.70 s ± 56.60 s; p<0.0001; IOP measurements with RBT in both study arms were higher than those with GAT (15.20 ± 2.74 mmHg vs. 13.25 ± 2.47 mmHg, p=0.0247 and 16.76 ± 3.99 mmHg vs. 13.92 ± 2.08 mmHg, p=0.003, respectively. No difference was observed between RBT and GAT regarding the corneal epithelial damage caused by tonometry. Conclusion: IOP measurement is feasible in a greater number of children with RBT, and the examination was faster than that for GAT. Compared with GAT, RBT tended to overestimate the IOP. None of the methods induced marked corneal epithelial defects.

  2. Glaucoma and intraocular pressure in EPIC-Norfolk Eye Study: cross sectional study.

    Science.gov (United States)

    Chan, Michelle P Y; Broadway, David C; Khawaja, Anthony P; Yip, Jennifer L Y; Garway-Heath, David F; Burr, Jennifer M; Luben, Robert; Hayat, Shabina; Dalzell, Nichola; Khaw, Kay-Tee; Foster, Paul J

    2017-09-13

    Objectives To report the distribution of intraocular pressure (IOP) by age and sex and the prevalence of glaucoma.Design Community based cross sectional observational study.Setting EPIC-Norfolk cohort in Norwich and the surrounding rural and urban areas.Participants 8623 participants aged 48-92 recruited from the community who underwent ocular examination to identify glaucoma.Main outcome measures Prevalence and characteristics of glaucoma, distribution of IOP, and the sensitivity and specificity of IOP for case finding for glaucoma.Results The mean IOP in 8401 participants was 16.3 mm Hg (95% confidence interval 16.2 mm Hg to 16.3 mm Hg; SD 3.6 mm Hg). In 363 participants (4%), glaucoma was present in either eye; 314 (87%) had primary open angle glaucoma. In the remaining participants, glaucoma was suspected in 607 (7%), and 863 (10.0%) had ocular hypertension. Two thirds (242) of those with glaucoma had previously already received the diagnosis. In 76% of patients with newly diagnosed primary open angle glaucoma (83/107), the mean IOP was under the threshold for ocular hypertension (21 mm Hg). No one IOP threshold provided adequately high sensitivity and specificity for diagnosis of glaucoma.Conclusions In this British community, cases of glaucoma, suspected glaucoma, and ocular hypertension represent a large number of potential referrals to the hospital eye service. The use of IOP for detection of those with glaucoma is inaccurate and probably not viable. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  3. Comparison of sugammadex and neostigmine–atropine on intraocular pressure and postoperative effects

    Directory of Open Access Journals (Sweden)

    Sedat Hakimoğlu

    2016-02-01

    Full Text Available During surgery, changes in intraocular pressure (IOP can be observed resulting from several factors, such as airway manipulations and drugs used. We aimed to investigate the effects of sugammadex and neostigmine on IOP, hemodynamic parameters, and complications after extubation. Our study comprised 60 patients, aged 18–65 years, with a risk status of the American Society of Anesthesiologists I–II who underwent arthroscopic surgery under general anesthesia. The patients were randomly assigned into two groups. At the end of the surgery, the neuromuscular block was reversed using neostigmine (50 μg/kg plus atropine (15 μg/kg in Group 1, and sugammadex (4 mg/kg in Group 2. Neuromuscular blockade was monitored using acceleromyography and a train-of-four mode of stimulation. IOP was measured before induction and at 30 seconds, 2 minutes, and 10 minutes after extubation. A Tono-Pen XL applanation tonometer was used to measure IOP. This showed that elevation in IOP of patients reversed using sugammadex was similar to that recorded in patients reversed using neostigmine–atropine. When heart rate was compared, there was a significant difference between basal values and those obtained at 30 seconds and 10 minutes after extubation in the neostigmine–atropine group. Extubation time (time from withdrawal of anesthetic gas to extubation was significantly shorter in the sugammadex group (p = 0.003 than in the neostigmine–atropine group. The postextubation IOP values of the sugammadex group were similar to the neostigmine–atropine group. Extubation time (time from withdrawal of anesthetic gas to extubation was significantly shorter in the sugammadex group (p = 0.003 than in the neostigmine–atropine group.

  4. INTRAOCULAR PRESSURE, MEAN ARTERIAL BLOOD PRESSURE AND PUPILLARY DIAMETER IN RABBITS ( (Oryctolagus cuniculus) ) SUBJECTED TO RETROBULBAR BLOCK WITH DIFFERENT ANESTHETIC PROTOCOLS

    OpenAIRE

    Renata Maria Monção da Silva; Francisco de Assis Dórea Neto; Vivian Fernanda Barbosa; Newton Nunes; Emanoel Ferreira Martins Filho; Arianne Pontes Oria

    2015-01-01

    The aim of this study was to evaluate four protocols of loco regional anesthesia for ophthalmic procedures that could provide safety and life support, in addition to maintain intraocular pressure stable, with eye centralization and eyelid akinesia. 20 New Zealand rabbits were used to perform local anesthesia by retrobulbar block with four protocols: 2% lidocaine with epinephrine, 2% lidocaine without epinephrine associated with tramadol, 1% ropivacaine and bupivacaine 0.5 %. Each animal recei...

  5. Intraocular pressure and associations in children. The Gobi Desert Children Eye Study.

    Directory of Open Access Journals (Sweden)

    Da Yong Yang

    Full Text Available To assess the intraocular pressure (IOP and its association in children in a population living in an oasis in the Gobi Desert.The cross-sectional school-based study included all schools in the Ejina region. The children underwent an ophthalmic examination, non-contact tonometry and measurement of blood pressure and body height and weight.Out of eligible 1911 children, 1565 (81.9% children with a mean age of 11.9±3.5 years (range: 6-21 years participated. Mean spherical refractive error was -1.58±2.00 diopters. In multivariate analysis, higher IOP (right eye was associated with younger age (P<0.001; standardized coefficient beta: -0.13; regression coefficient B: -0.13; 95% Confidence interval (CI:-0.18, -0.07, higher diastolic blood pressure (P<0.001;beta:0.13;B:0.05;95%CI:0.03,0.07, higher corneal refractive power (P<0.001;beta:0.11;B:0.23;95%CI:0.12,0.34, more myopic refractive error (P = 0.035;beta: -0.06;B: -0.10;95%CI: -0.19, -0.001, and Han Chinese ethnicity of the father (P = 0.03;beta:0.06;B:0.42;95%CI:0.04,0.89. If age and diastolic blood pressure were dropped, higher IOP was associated with higher estimated cerebrospinal fluid pressure (CSFP (P<0.001;beta:0.09; B:0.13;95%CI:0.06,0.21 after adjusting for higher corneal refractive power (P<0.001 and Han Chinese ethnicity of the father (P = 0.04. Correspondingly, higher IOP of the left eye was associated with younger age (P<0.001;beta: -0.15;B: -0.16;95%CI: -0.21, -0.10, female gender (P<0.001;beta:0.09;B:0.65;95%CI:0.30,1.01, higher corneal refractive power (P<0.001;beta:0.08;B:0.19;95%CI:0.06,0.32, more myopic refractive error (P = 0.03;beta: -0.06;B: -0.12;95%CI: -0.22, -0.01, and higher estimated CSFP (P<0.001;beta:0.11;B:0.17;95%CI:0.09,0.24.In school children, higher IOP was associated with steeper corneal curvature and with younger age and higher blood pressure, or alternatively, with higher estimated CSFP. Corneal curvature radius should be included in the

  6. Regulation of intraocular pressure in mice: structural analysis of dopaminergic and serotonergic systems in response to cabergoline.

    Science.gov (United States)

    Platania, Chiara Bianca Maria; Leggio, Gian Marco; Drago, Filippo; Salomone, Salvatore; Bucolo, Claudio

    2013-11-01

    Elevated intraocular pressure (IOP) is the main recognized risk factor of glaucoma. To investigate the contribution of dopaminergic and serotonergic systems in IOP regulation, we used cabergoline, a mixed dopamine and serotonin agonist, in C57BL/6J WT and dopamine D₃ receptor knock-out (D₃R⁻/⁻) mice with normal eye pressure or steroid-induced ocular hypertension. Furthermore, we studied the structural basis of the cabergoline-mediated activation of the dopaminergic and serotonergic systems by molecular modeling. Topical application of cabergoline, significantly decreased, in a dose-dependent manner, the intraocular pressure in WT mice, both in an ocular normotensive group (-9, -5 and -2 mmHg with 5%, 1%, and 0.1%, respectively) and an ocular hypertensive group, with a prolonged effect in this latter group. No change of intraocular pressure was observed after topical application of cabergoline in D₃R⁻/⁻ mice. We modeled and optimized, with molecular dynamics, structures of hD₃, h5HT(1A) and h5HT(2A-C) receptors; thereafter we carried out molecular docking of cabergoline. Docking revealed that binding of cabergoline into D₃ and 5HT(1A) receptors is associated with a better desolvation energy in comparison to 5HT(2A-C) binding. In conclusion, the present study support the hypothesis that dopaminergic system is pivotal to regulate IOP and that D₃R represents an intriguing target in the treatment of glaucoma. Furthermore, the structure-based computational approach adopted in this study is able to build and refine structure models of homologous dopaminergic and serotonergic receptors that may be of interest for structure-based drug discovery of ligands, with dopaminergic selectivity or with multi-pharmacological profile, potentially useful to treat optic neuropathies. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Effect of caffeine on the intraocular pressure in patients with primary open angle glaucoma.

    Science.gov (United States)

    Chandra, Peeyush; Gaur, Ajit; Varma, Shambhu

    2011-01-01

    Coffee and tea are very common nonalcoholic beverages. However, their intake, particularly that of coffee, has been suggested to increase intraocular pressure (IOP) in patients with open angle glaucoma/ocular hypertension. The causative agent has been suggested to be their caffeine content. The objective of this study was to determine if this represents a direct caffeine effect. This study was therefore done using pure caffeine applied directly to the eyes. The study was conducted with five human volunteers with open angle glaucoma/ ocular hypertension. IOP was measured using a Perkins applanation tonometer. Eye drops of 1% caffeine were prepared in-home. Following the initial (basal) measurement of the IOP, 50 μL of the eye drop preparation was instilled in the eye at 0-, 4-, and 6-hour intervals. IOPs were measured 30 minutes after each instillation. A second study was also undertaken following the first. In this study, the same patients instilled the eye drops three times per day for 1 week at home and then returned to the clinic on day 7. They were then again treated with caffeine eye drops as above and IOPs measured. In the 1-day study, the mean basal IOP was 23.6 ± 2.80 mmHg. Thirty minutes after instillation of the drops as described, the pressures were 23.2 ± 1.93, 22.2 ± 1.99, and 22.6 ± 2.31. The basal reading was taken at 10 am and another reading was then taken at 10.30 am. Additional eye drops were instilled at 2 and 8 pm and readings taken 30 minutes after each instillation. In the 1 week study, the basal value was 22.6 ± 2.32. After instillation of the drops as above the values were 23 ± 2.16, 22.4 ± 2.27, and 23 ± 1.94. Administration of caffeine into the eyes of patients did not have any effect on IOP and it remained relatively unchanged. This was true in the 1-day study as well as in the 1-week study. A cumulative effect was not visible. The results therefore demonstrate that caffeine has no significant effect on IOP in patients with

  8. Short-term reproducibility of intraocular pressure and ocular perfusion pressure measurements in Chinese volunteers and glaucoma patients.

    Science.gov (United States)

    Gao, Yanlin; Wan, Bing; Li, Peiyu; Zhang, Yan; Tang, Xin

    2016-08-18

    To evaluate the short-term reproducibility of diurnal intraocular pressure (IOP) and ocular perfusion pressure (OPP) measurements in normal volunteers, untreated normal-tension glaucoma (NTG) and primary open-angle glaucoma (POAG) patients. Fifty-four healthy volunteers (control group), 67 NTG patients and 54 POAG patients were recruited. The IOPs of both eyes were measured with a Goldmann applanation tonometer at 3-h intervals over 2 consecutive days. Blood pressure (BP) measurements were collected at the same times. The mean IOP/OPP, peak IOP/OPP, trough IOP/OPP and IOP/OPP fluctuations on each day were also calculated. The intraclass correlation coefficients (ICCs) were used to evaluate the reproducibilities. In the control group, the ICCs of mean IOP, peak IOP, trough IOP and IOP fluctuation were 0.921, 0.889, 0.888, and 0.661, respectively, and the ICCs of the mean OPP, peak OPP, trough OPP and OPP fluctuations were 0.962, 0.918, 0.953, and 0.680, respectively. In the NTG group, the ICCs of the mean IOP, peak IOP, trough IOP and IOP fluctuation were 0.862, 0.741, 0.798, and 0.290, respectively, and the ICCs of the mean OPP, peak OPP, trough OPP and OPP fluctuations were 0.947, 0.828, 0.927, and -0.008, respectively. In the POAG group, the ICCs of the mean IOP, peak IOP, trough IOP and IOP fluctuation were 0.857, 0.666, 0.808, and 0.546, respectively, and the ICCs of the mean OPP, peak OPP, trough OPP and OPP fluctuation were 0.934, 0.842, 0.910, and 0.093, respectively. The IOP measurements within a single day were not highly reproducible in the short-term. The normal volunteers exhibited better IOP and OPP reproducibilities than the glaucoma patients. The IOP and OPP fluctuations could not be accurately evaluated based on the IOP or OPP measurements within a single day.

  9. Effect of persistent high intraocular pressure on microstructure and hydraulic permeability of trabecular meshwork

    Science.gov (United States)

    Mei, Xi; Ren, Lin; Xu, Qiang; Zheng, Wei; Liu, Zhi-Cheng

    2015-05-01

    As the aqueous humor leaves the eye, it first passes through the trabecular meshwork (TM). Increased flow resistance in this region causes elevation of intraocular pressure (IOP), which leads to the occurrence of glaucoma. To quantitatively evaluate the effect of high IOP on the configuration and hydraulic permeability of the TM, second harmonic generation (SHG) microscopy was used to image the microstructures of the TM and adjacent tissues in control (normal) and high IOP conditions. Enucleated rabbit eyes were perfused at a pressure of 60 mmHg to achieve the high IOP. Through the anterior chamber of the eye, in situ images were obtained from different depths beneath the surface of the TM. Porosity and specific surface area of the TM in control and high IOP conditions were then calculated to estimate the effect of the high pressure on the permeability of tissue in different depths. We further photographed the histological sections of the TM and compared the in situ images. The following results were obtained in the control condition, where the region of depth was less than 55 μm with crossed branching beams and large pores in the superficial TM. The deeper meshwork is a silk-like tissue with abundant fluorescence separating the small size of pores. The total thickness of pathway tissues composed of TM and juxtacanalicular (JCT) is more than 100 μm. After putting a high pressure on the inner wall of the eye, the TM region progressively collapses and decreases to be less than 40 μm. Fibers of the TM became dense, and the porosity at 34 μm in the high IOP condition is comparable to that at 105 μm in the control condition. As a consequent result, the permeability of the superficial TM decreases rapidly from 120 μm2 to 49.6 μm2 and that of deeper TM decreases from 1.66 μm2 to 0.57 μm2. Heterogeneity reflected by descent in permeability reduces from 12.4 μm of the control condition to 3.74 μm of the high IOP condition. The persistently high IOP makes the TM

  10. Correlation between diurnal variation of intraocular pressure, ocular pulse amplitude and corneal structural properties Correlação entre a variação diurna da pressão intraocular, amplitude de pulso e propriedades estruturais corneanas

    Directory of Open Access Journals (Sweden)

    Flávia Silva Villas-Bôas

    2009-06-01

    Full Text Available PURPOSE: The purpose of this study was to evaluate the fluctuation of intraocular pressure measurements obtained by Goldmann applanation tonometry, dynamic contour tonometry, and corneal compensated non-contact tonometry during office hours in glaucoma and healthy participants. This study also aims at correlating the intraocular pressure fluctuations with fluctuations of corneal hysteresis, central corneal thickness, mean central corneal curvature and ocular pulse amplitude. METHODS: A total of 12 controls (24 eyes and 21 patients (38 eyes with open-angle glaucoma were recruited. Intraocular pressure measured by Goldmann applanation tonometry, dynamic contour tonometry and corneal compensated non-contact tonometry, ocular pulse amplitude, central corneal curvature and thickness, corneal hysteresis, and resistance factor were obtained at intervals of 2 hours, between 9 AM and 5 PM. RESULTS: Intraocular pressure fluctuated significantly throughout the day in controls and glaucoma individuals with all tonometers (POBJETIVO: Avaliar a flutuação das medidas da pressão intraocular obtidas pela tonometria de aplanação de Goldmann, tonometria de contorno dinâmico e pela tonometria de não-contato com compensação corneana durante o período ambulatorial, em participantes com glaucoma e saudáveis. Esse estudo também correlacionou as flutuações da pressão intraocular com as flutuações da histerese corneana, espessura corneana central, média da curvatura corneana central e amplitude de pulso ocular. MÉTODOS: Um total de 12 controles (24 olhos e 21 pacientes com glaucoma de ângulo aberto (38 olhos foram selecionados. A pressão intraocular medida pela tonometria de aplanação de Goldmann, tonometria de contorno dinâmico e tonometria de não-contato com compensação corneana, amplitude de pulso ocular, a curvatura central e espessura corneanas, a histerese corneana e o fator de resistência foram medidos em intervalos de 2 horas, entre 9

  11. Sustainability of Intraocular Pressure Reduction of Travoprost Ophthalmic Solution in Subjects with Normal Tension Glaucoma.

    Science.gov (United States)

    Naito, Tomoko; Okuma, Shinichi; Nagayama, Mikio; Mizoue, Shiro; Ozaki, Mineo; Namiguchi, Koji; Miyamoto, Kazuhisa; Tanito, Masaki; Yoshikawa, Keiji

    2016-03-01

    We examined the sustainability of the intraocular pressure (IOP)-lowering efficacy of travoprost (0.004%) ophthalmic solution in subjects with normal tension glaucoma (NTG). Travoprost ophthalmic solution was given once daily at 9 PM to subjects with newly diagnosed NTG or with NTG who had not received any ocular hypotensives within the previous 30 days. IOP was measured at three time points (9 AM, 1 PM, and 5 PM) at baseline and week 12 visits, and at one time point (9 AM) at week 4 and week 8 visits. Conjunctival hyperemia, superficial punctate keratopathy, and other adverse events were evaluated during the observation period. Thirty subjects (12 males and 18 females; mean age 65.6 years) from 32 subjects enrolled were included in the efficacy analysis. The mean IOPs (±standard deviation) of 16.6 ± 1.4, 15.7 ± 1.8, and 15.7 ± 2.2 mmHg at 9 AM, 1 PM, and 5 PM, respectively, at baseline reduced significantly to the mean IOPs of 13.0 ± 1.8, 12.7 ± 1.8, and 12.8 ± 1.6 mmHg, respectively, at week 12 (P < 0.0001 for every time point). Together with the mean IOPs of 13.4 ± 1.9 mmHg at week 4 and 13.2 ± 1.9 mmHg at week 8, the pooled IOP during the observation period for up to 12 weeks showed a statistically and clinically significant reduction of IOP at 9 AM. (3.4 mmHg or 20.3% reduction from baseline, P < 0.0001). There were no adverse events leading to treatment discontinuation. This multi-center collaborative study suggests that IOP-lowering efficacy of travoprost ophthalmic solution persists during the day at the clinically relevant level in subjects with NTG. Alcon Japan Ltd. University Hospital Medical Information Network, UMIN ID: 000011621.

  12. Intraocular Pressure-Lowering Effect of Latanoprost Is Hampered by Defective Cervical Lymphatic Drainage.

    Directory of Open Access Journals (Sweden)

    Young Kook Kim

    Full Text Available To evaluate whether defects in cervical lymphatic drainage influence the intraocular pressure (IOP-lowering effect of latanoprost in patients with primary open-angle glaucoma (POAG who have undergone unilateral radical neck dissection (uRND.We enrolled (1 bilateral POAG patients who had started (bilateral latanoprost (0.005% monotherapy prior to their uRND and (2 treatment-naïve, bilateral glaucoma suspects (GSs who had undergone the same surgery. We compared the eyes ipsilateral to the uRND with their fellow eyes in terms of the changes in IOP between the baseline (prior to the uRND and the follow-up visits (1, 3, and 6 months after the uRND.The study involved 22 eyes of 11 POAG patients and 14 eyes of 7 GSs. In the POAG patients, IOP had increased significantly after surgery in the eyes ipsilateral to the uRND (from 14.7±1.4mmHg to 17.1±2.2mmHg; P = 0.007. Interestingly, in the eyes contralateral to the uRND, IOP had not changed significantly after surgery (from 14.2±1.8mmHg to 14.4±2.0mmHg; P = 0.826. In GSs, the eyes ipsilateral to the uRND did not differ significantly from their fellow eyes in terms of post-operative IOP change (ipsilateral value: 0.3±0.5mmHg, fellow eyes: -0.1±0.7mmHg; P = 0.242.In the POAG patients, IOP had increased significantly in the eyes ipsilateral to the uRND. However, it had not changed significantly in the eyes contralateral to the surgery or in the eyes of the GSs. These findings suggest that, latanoprost works, at least in part, by enhancing outflow from the aqueous humor via the uveolymphatic pathway.

  13. Latrunculin B Reduces Intraocular Pressure in Human Ocular Hypertension and Primary Open-Angle Glaucoma

    Science.gov (United States)

    Rasmussen, Carol A.; Kaufman, Paul L.; Ritch, Robert; Haque, Reza; Brazzell, R. Kim; Vittitow, Jason L.

    2014-01-01

    Purpose To evaluate the safety, tolerability, and intraocular pressure (IOP)-lowering effect of Latrunculin-B (Lat-B), a marine macrolide that disrupts the actin cytoskeleton, in patients with ocular hypertension (OHT) or early primary open-angle glaucoma (POAG). Methods In this Phase I, multicenter, double-masked, randomized, placebo-controlled, ascending-dose study, subjects with bilateral OHT or early POAG (>22 mm Hg) received one of four concentrations of INS115644 (Lat-B ophthalmic solutions, 0.005%, 0.01%, 0.02%, or 0.05%) in one eye over 3 days (5 single-dose instillations, separated by 12 hours). One eye was randomly assigned to active drug, the other to placebo. IOP was measured prior to treatment initiation (day 0) and on days 1 and 3. Results Baseline IOPs were 22.9 ± 2.4 mm Hg and 23.5 + 3.1 mm Hg in the 0.02% and 0.05% dose groups, respectively. At 4 hours post instillation of the first dose, 0.02% INS115644 reduced IOP from baseline (mean ± SE) by 3.8 ± 0.7 mm Hg (P = 0.002) and 0.05% by 3.9 ± 1.0 mm Hg (P = 0.004). A maximum IOP decrease of 24% was noted at 4 hours after the fifth instillation of 0.02%. Adjusting for diurnal baseline and IOP in the contralateral, placebo-treated eye, the maximal 12-hour hypotensive effect was 4.0 ± 0.5 mm Hg (adjusted mean ± SE), a 17% decrease, following the fifth instillation of 0.02% (day 3). Adverse events were few and consisted mainly of mild redness, irritation, and a transient, clinically insignificant increase (≤2.5%) in central corneal thickness. Conclusions In OHT or POAG patients, twice daily Lat-B significantly lowered IOP compared with contralateral, placebo-treated eyes, with few and mild ocular adverse events. Translational Relevance Lat-B may be a potential therapeutic agent for glaucoma. PMID:25237590

  14. Intraocular pressure and ocular pulse amplitude using dynamic contour tonometry and contact lens tonometry

    Directory of Open Access Journals (Sweden)

    Grus Franz-H

    2004-03-01

    Full Text Available Abstract Background The new Ocular Dynamic Contour Tonometer (DCT, investigational device supplied by SMT (Swiss Microtechnology AG, Switzerland allows simultaneous recording of intraocular pressure (IOP and ocular pulse amplitude (OPA. It was the aim of this study to compare the IOP results of this new device with Goldmann tonometry. Furthermore, IOP and OPA measured with the new slitlamp-mounted DCT were compared to the IOP and OPA measured with the hand-held SmartLens®, a gonioscopic contact lens tonometer (ODC Ophthalmic Development Company AG, Switzerland. Methods Nineteen healthy subjects were included in this study. IOP was determined by three consecutive measurements with each of the DCT, SmartLens®, and Goldmann tonometer. Furthermore, OPA was measured three times consecutively by DCT and SmartLens®. Results No difference (P = 0.09 was found between the IOP values by means of DCT (mean: 16.6 mm Hg, median: 15.33 mm Hg, SD: +/- 4.04 mm Hg and Goldmann tonometry (mean: 16.17 mm Hg, median: 15.33 mm Hg, SD: +/- 4.03 mm Hg. The IOP values of SmartLens® (mean: 20.25 mm Hg, median: 19.00 mm Hg, SD: +/- 4.96 mm Hg were significantly higher (P = 0.0008 both from Goldmann tonometry and DCT. The OPA values of the DCT (mean: 3.08 mm Hg, SD: +/- 0.92 mm Hg were significantly lower (P = 0.0003 than those obtained by SmartLens® (mean: 3.92 mm Hg, SD: +/- 0.83 mm Hg. Conclusions DCT was equivalent to Goldmann applanation tonometry in measurement of IOP in a small group of normal subjects. In contrast, SmartLens® (contact lens tonometry gave IOP readings that were significantly higher compared with Goldmann applanation tonometer readings. Both devices, DCT and SmartLens® provide the measurement of OPA which could be helpful e.g. for the management of glaucoma.

  15. The impact of intraocular pressure on elastic wave velocity estimates in the crystalline lens

    Science.gov (United States)

    Park, Suhyun; Yoon, Heechul; Larin, Kirill V.; Emelianov, Stanislav Y.; Aglyamov, Salavat R.

    2017-02-01

    Intraocular pressure (IOP) is believed to influence the mechanical properties of ocular tissues including cornea and sclera. The elastic properties of the crystalline lens have been mainly investigated with regard to presbyopia, the age-related loss of accommodation power of the eye. However, the relationship between the elastic properties of the lens and IOP remains to be established. The objective of this study is to measure the elastic wave velocity, which represents the mechanical properties of tissue, in the crystalline lens ex vivo in response to changes in IOP. The elastic wave velocities in the cornea and lens from seven enucleated bovine globe samples were estimated using ultrasound shear wave elasticity imaging. To generate and then image the elastic wave propagation, an ultrasound imaging system was used to transmit a 600 µs pushing pulse at 4.5 MHz center frequency and to acquire ultrasound tracking frames at 6 kHz frame rate. The pushing beams were separately applied to the cornea and lens. IOP in the eyeballs was varied from 5 to 50 mmHg. The results indicate that while the elastic wave velocity in the cornea increased from 0.96  ±  0.30 m s-1 to 6.27  ±  0.75 m s-1 as IOP was elevated from 5 to 50 mmHg, there were insignificant changes in the elastic wave velocity in the crystalline lens with the minimum and the maximum speeds of 1.44  ±  0.27 m s-1 and 2.03  ±  0.46 m s-1, respectively. This study shows that ultrasound shear wave elasticity imaging can be used to assess the biomechanical properties of the crystalline lens noninvasively. Also, it was observed that the dependency of the crystalline lens stiffness on the IOP was significantly lower in comparison with that of cornea.

  16. Additive effects of genetic variants associated with intraocular pressure in primary open-angle glaucoma.

    Science.gov (United States)

    Mabuchi, Fumihiko; Mabuchi, Nakako; Sakurada, Yoichi; Yoneyama, Seigo; Kashiwagi, Kenji; Iijima, Hiroyuki; Yamagata, Zentaro; Takamoto, Mitsuko; Aihara, Makoto; Iwata, Takeshi; Kawase, Kazuhide; Shiga, Yukihiro; Nishiguchi, Koji M; Nakazawa, Toru; Ozaki, Mineo; Araie, Makoto

    2017-01-01

    To investigate the association between the additive effects of genetic variants associated with intraocular pressure (IOP) and IOP, vertical cup-to-disc ratio (VCDR), and high tension glaucoma (HTG) or normal tension glaucoma (NTG) as phenotypic features of primary open-angle glaucoma (POAG), and to evaluate the clinical usefulness of the additive effects of IOP-related genetic variants for predicting IOP elevation, Japanese patients with HTG (n = 255) and NTG (n = 261) and 246 control subjects were genotyped for nine IOP-related genetic variants near CAV2, GAS7, GLCCI1/ICA1, ABCA1, ARHGEF12, FAM125B, FNDC3B, ABO, and PTPRJ/AGBL2. The total number of risk alleles of these genetic variants was calculated for each participant as a genetic risk score (GRS), and the association between the GRS and the maximum IOP, mean VCDR, and phenotype (HTG or NTG) of POAG was evaluated. As the GRS increased, the maximum IOP (P = 0.012) and VCDR (P = 0.010) significantly increased. The GRS (9.1±1.9) in patients with HTG was significantly higher (P = 0.011) than that (8.7±1.8) in control subjects. The patients with GRS≥12 as a cut-off value had a 2.54 times higher (P = 0.0085) risk on HTG (maximum IOP≥22mmHg) compared with all patients. The IOP-related GRS approach substantiated that the IOP and VCDR were increased by the additive effects of IOP-related genetic variants in POAG. The high IOP-related GRS in patients with HTG but not NTG shows that there are differences in the genetic background between HTG and NTG and supports the notion that the phenotype (HTG or NTG) in patients with POAG depends on the additive effects of IOP-related genetic variants. The above-mentioned cut-off value of IOP-related GRS may be clinically useful for predicting the risk of IOP elevation.

  17. Additive effects of genetic variants associated with intraocular pressure in primary open-angle glaucoma.

    Directory of Open Access Journals (Sweden)

    Fumihiko Mabuchi

    Full Text Available To investigate the association between the additive effects of genetic variants associated with intraocular pressure (IOP and IOP, vertical cup-to-disc ratio (VCDR, and high tension glaucoma (HTG or normal tension glaucoma (NTG as phenotypic features of primary open-angle glaucoma (POAG, and to evaluate the clinical usefulness of the additive effects of IOP-related genetic variants for predicting IOP elevation, Japanese patients with HTG (n = 255 and NTG (n = 261 and 246 control subjects were genotyped for nine IOP-related genetic variants near CAV2, GAS7, GLCCI1/ICA1, ABCA1, ARHGEF12, FAM125B, FNDC3B, ABO, and PTPRJ/AGBL2. The total number of risk alleles of these genetic variants was calculated for each participant as a genetic risk score (GRS, and the association between the GRS and the maximum IOP, mean VCDR, and phenotype (HTG or NTG of POAG was evaluated. As the GRS increased, the maximum IOP (P = 0.012 and VCDR (P = 0.010 significantly increased. The GRS (9.1±1.9 in patients with HTG was significantly higher (P = 0.011 than that (8.7±1.8 in control subjects. The patients with GRS≥12 as a cut-off value had a 2.54 times higher (P = 0.0085 risk on HTG (maximum IOP≥22mmHg compared with all patients. The IOP-related GRS approach substantiated that the IOP and VCDR were increased by the additive effects of IOP-related genetic variants in POAG. The high IOP-related GRS in patients with HTG but not NTG shows that there are differences in the genetic background between HTG and NTG and supports the notion that the phenotype (HTG or NTG in patients with POAG depends on the additive effects of IOP-related genetic variants. The above-mentioned cut-off value of IOP-related GRS may be clinically useful for predicting the risk of IOP elevation.

  18. Genetic context determines susceptibility to intraocular pressure elevation in a mouse pigmentary glaucoma

    Directory of Open Access Journals (Sweden)

    Cosma Ioan M

    2006-07-01

    Full Text Available Abstract Background DBA/2J (D2 mice develop an age-related form of glaucoma. Their eyes progressively develop iris pigment dispersion and iris atrophy followed by increased intraocular pressure (IOP and glaucomatous optic nerve damage. Mutant alleles of the Gpnmb and Tyrp1 genes are necessary for the iris disease, but it is unknown whether alleles of other D2 gene(s are necessary for the distinct later stages of disease. We initiated a study of congenic strains to further define the genetic requirements and disease mechanisms of the D2 glaucoma. Results To further understand D2 glaucoma, we created congenic strains of mice on the C57BL/6J (B6 genetic background. B6 double-congenic mice carrying D2-derived Gpnmb and Tyrp1 mutations develop a D2-like iris disease. B6 single-congenics with only the Gpnmb and Tyrp1 mutations develop milder forms of iris disease. Genetic epistasis experiments introducing a B6 tyrosinase mutation into the congenic strains demonstrated that both the single and double-congenic iris diseases are rescued by interruption of melanin synthesis. Importantly, our experiments analyzing mice at ages up to 27 months indicate that the B6 double-congenic mice are much less prone to IOP elevation and glaucoma than are D2 mice. Conclusion As demonstrated here, the Gpnmb and Tyrp1 iris phenotypes are both individually dependent on tyrosinase function. These results support involvement of abnormal melanosomal events in the diseases caused by each gene. In the context of the inbred D2 mouse strain, the glaucoma phenotype is clearly influenced by more genes than just Gpnmb and Tyrp1. Despite the outward similarity of pigment-dispersing iris disease between D2 and the B6 double-congenic mice, the congenic mice are much less susceptible to developing high IOP and glaucoma. These new congenic strains provide a valuable new resource for further studying the genetic and mechanistic complexity of this form of glaucoma.

  19. Intraocular pressure, corneal thickness, and corneal hysteresis in Steinert's myotonic dystrophy.

    Science.gov (United States)

    Garcia Filho, Carlos Alexandre de A; Prata, Tiago Santos; Sousa, Aline Katia Siqueira; Doi, Larissa Morimoto; Melo Jr, Luiz Alberto Soares

    2011-01-01

    Low intraocular pressure (IOP) measured by Goldmann applanation tonometry (GAT) is one of the ocular manifestations of Steinert's myotonic dystrophy. The goal of this study was to evaluate the corneal-compensated IOP as well as corneal properties (central corneal thickness and corneal hysteresis) in patients with myotonic dystrophy. A total of 12 eyes of 6 patients with Steinert's myotonic dystrophy (dystrophy group) and 12 eyes of 6 age-, race-, and gender-matched healthy volunteers (control group) were included in the study. GAT, Dynamic Contour Tonometry (DCT-Pascal) and Ocular Response Analyzer (ORA) were used to assess the IOP. Central corneal thickness was obtained by ultrasound pachymetry, and corneal hysteresis was analyzed using the ORA device. In light of the multiplicity of tests performed, the significance level was set at 0.01 rather than 0.05. The mean (standard deviation [SD]) GAT, DCT, and corneal-compensated ORA IOP in the dystrophy group were 5.4 (1.4) mmHg, 9.7 (1.5) mmHg, and 10.1 (2.6) mmHg, respectively. The mean (SD) GAT, DCT, and corneal-compensated ORA IOP in the control group was 12.6 (2.9) mmHg, 15.5 (2.7) mmHg, and 15.8 (3.4) mmHg, respectively. There were significant differences in IOP values between dystrophy and control groups obtained by GAT (mean, -7.2 mmHg; 99% confidence interval [CI], -10.5 to -3.9 mmHg; Pcorneal-compensated ORA measurements (mean, -5.7 mmHg; 99% CI, -10.4 to -1.0 mmHg; P=0.003). The mean (SD) central corneal thickness was similar in the dystrophy (542 [31] µm) and control (537 [11] µm) groups (P=0.65). The mean (SD) corneal hysteresis in the dystrophy and control groups were 11.2 (1.5) mmHg and 9.7 (1.2) mmHg, respectively (P=0.04). Patients with Steinert's myotonic dystrophy showed lower Goldmann and corneal-compensated IOP in comparison with healthy individuals. Since central corneal thickness and corneal hysteresis did not differ significantly between groups, the lower IOP readings documented in this

  20. Intraocular pressure, corneal thickness, and corneal hysteresis in Steinert's myotonic dystrophy

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre de A. Garcia Filho

    2011-06-01

    Full Text Available PURPOSE: Low intraocular pressure (IOP measured by Goldmann applanation tonometry (GAT is one of the ocular manifestations of Steinert's myotonic dystrophy. The goal of this study was to evaluate the corneal-compensated IOP as well as corneal properties (central corneal thickness and corneal hysteresis in patients with myotonic dystrophy. METHODS: A total of 12 eyes of 6 patients with Steinert's myotonic dystrophy (dystrophy group and 12 eyes of 6 age-, race-, and gender-matched healthy volunteers (control group were included in the study. GAT, Dynamic Contour Tonometry (DCT-Pascal and Ocular Response Analyzer (ORA were used to assess the IOP. Central corneal thickness was obtained by ultrasound pachymetry, and corneal hysteresis was analyzed using the ORA device. In light of the multiplicity of tests performed, the significance level was set at 0.01 rather than 0.05. RESULTS: The mean (standard deviation [SD] GAT, DCT, and corneal-compensated ORA IOP in the dystrophy group were 5.4 (1.4 mmHg, 9.7 (1.5 mmHg, and 10.1 (2.6 mmHg, respectively. The mean (SD GAT, DCT, and corneal-compensated ORA IOP in the control group was 12.6 (2.9 mmHg, 15.5 (2.7 mmHg, and 15.8 (3.4 mmHg, respectively. There were significant differences in IOP values between dystrophy and control groups obtained by GAT (mean, -7.2 mmHg; 99% confidence interval [CI], -10.5 to -3.9 mmHg; P<0.001, DCT (mean, -5.9 mmHg; 99% CI, -8.9 to -2.8 mmHg; P<0.001, and corneal-compensated ORA measurements (mean, -5.7 mmHg; 99% CI, -10.4 to -1.0 mmHg; P=0.003. The mean (SD central corneal thickness was similar in the dystrophy (542 [31] µm and control (537 [11] µm groups (P=0.65. The mean (SD corneal hysteresis in the dystrophy and control groups were 11.2 (1.5 mmHg and 9.7 (1.2 mmHg, respectively (P=0.04. CONCLUSIONS: Patients with Steinert's myotonic dystrophy showed lower Goldmann and corneal-compensated IOP in comparison with healthy individuals. Since central corneal thickness and

  1. Predictors of additional intraocular pressure reduction in patients changed to latanoprost/timolol fixed combination

    Directory of Open Access Journals (Sweden)

    Nordmann Jean-Philippe

    2010-03-01

    Full Text Available Abstract Background Given the growing number of ocular hypotensive medications available, it is important to be able to predict a positive response to therapy. The purpose of the present study was to identify predictors of an additional 10% intraocular pressure (IOP reduction after 12 weeks of treatment with latanoprost/timolol fixed combination (FC in patients requiring a change in their previous ocular hypotensive medication. Methods This multicenter, open-label, prospective, phase IIIb study included subjects ≥18 years of age with open-angle glaucoma (OAG or ocular hypertension (OHT. Eligible subjects had baseline IOP ≥21 mmHg and insufficient response to current beta-blocker monotherapy. The primary efficacy analysis (logistic regression identified predictors of a positive response after 12 weeks of latanoprost/timolol FC. Results The intent-to-treat (ITT population included 383 subjects treated with ≥1 drop of FC and having ≥1 follow-up IOP assessment. Mean IOP was 22.19 ± 2.16 mmHg at baseline and was reduced by 5.42 ± 2.71 mmHg at study end. In all, 325 (84.9% subjects had a positive response to latanoprost/timolol FC; the response rate was similar across groups: OAG (n = 208; 82.7%; OHT (n = 161; 87.6%; OAG+OHT (n = 14; 85.7%. Higher baseline IOP (odds ratio: 1.284; 95% confidence interval [CI]: 1.101, 1.497; p = 0.0014 and absence of adverse events (odds ratio: 0.318; 95% CI: 0.161, 0.629; p = 0.0010 were significant predictors of positive response. Age, gender, ethnic origin, diagnosis, family history of OAG/OHT, corneal thickness, and concomitant systemic beta-blocker were not significant predictors of a positive response in the ITT analysis. The FC was well tolerated. The most common adverse events were related to the eye and were consistent with known adverse events associated with latanoprost and timolol. Conclusions These results support the use of latanoprost/timolol FC in patients whose IOP is insufficiently controlled

  2. Intraocular pressure measurement precision with the Goldmann applanation, dynamic contour, and ocular response analyzer tonometers.

    Science.gov (United States)

    Kotecha, Aachal; White, Edward; Schlottmann, Patricio G; Garway-Heath, David F

    2010-04-01

    To examine the repeatability and reproducibility of intraocular pressure (IOP) measurements obtained with the Goldmann applanation tonometer (GAT), the Pascal dynamic contour tonometer (DCT; Swiss Microtechnology AG, Port, Switzerland), and the Reichert Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments, Buffalo, NY). A secondary objective was to assess agreement between the devices. Evaluation of technology. One hundred participants; a mixture of glaucoma suspects, patients, and control volunteers. The IOP measurements were obtained with the GAT, DCT, and ORA by 2 of 3 experienced clinicians. Keratometry (CC) measurements were made using the IOLMaster (Carl Zeiss Meditech, AG, Jena, Germany). Three ORA corneal compensated IOP (IOPcc) measurements were obtained before the instillation of anesthesia, after which 2 GAT IOP and 3 DCT IOP measurements were obtained in a randomized order. Central corneal thickness (CCT) was measured using an ultrasound pachymeter. The average ORA corneal response factor (CRF) and the average DCT ocular pulse amplitude (OPA) were determined. Intraobserver variability was calculated by the repeatability coefficient. Interobserver variability (measurement reproducibility) and device agreement were calculated by Bland-Altman analysis (mean difference [bias] and 95% limits of agreement [LoA]). The effect of corneal characteristics (CC, CCT, and CRF) on the IOP measurement differences between tonometers also was determined. Repeatability and reproducibility of the GAT, DCT, and ORA IOPcc and agreement between tonometers. The repeatability coefficients for GAT, DCT, and ORA were 2.2, 2.3, and 4.3 mmHg, respectively. The intraobserver variability of ORA measurements was shown to be significantly associated with OPA and to a lesser degree with the quality of ORA waveform scans. The interobserver bias (95% LoA) was -0.8 (+/-3.9) mmHg for GAT -0.2 (+/-2.8) mmHg for DCT and -0.3 (+/-3.9) mmHg for ORA IOPcc. On average, GAT under

  3. The Effect of Phacoemulsification on Intraocular Pressure in Eyes with Hyperfiltration Following Trabeculectomy: A Prospective Study.

    Science.gov (United States)

    Riva, Ivano; Katsanos, Andreas; Oddone, Francesco; Quaranta, Luciano

    2017-12-08

    The aim of this study was to evaluate the effect of visually non-significant cataract extraction in patients with hypotony maculopathy and reduced visual acuity due to over-filtering blebs after trabeculectomy. Patients with intraocular pressure (IOP) < 6 mmHg and documented hypotony maculopathy due to over-filtering blebs after trabeculectomy were prospectively recruited. Eligible patients underwent visually non-significant cataract phacoemulsification, no earlier than 12 weeks from the diagnosis of hypotony maculopathy. IOP and visual acuity before and after phacoemulsification were compared at 1 and 3 months from surgery. Correlations between age, time interval between surgeries, baseline IOP, bleb type and IOP and visual acuity changes at 3 months after phacoemulsification were investigated. From January 2010 to September 2014, 20 consecutive adult patients met the inclusion criteria. Before phacoemulsification, mean IOP was 3.1 ± 1.6 mmHg. Following phacoemulsification, mean IOP increased to 8.6 ± 4.1 mmHg at 1 month (p < 0.01) and to 9.1 ± 4.3 mmHg at 3 months (p < 0.01). IOP elevation following phacoemulsification was observed in 16 of 20 eyes (80%). Mean visual acuity improved from Snellen 0.5 ± 0.1 to 0.6 ± 0.1 at 1 month (p < 0.01) to 0.7 ± 0.2 at 3 months (p < 0.01) after phacoemulsification. In 4 eyes in which the IOP was not elevated, surgical revision of the previous trabeculectomy was performed. No significant correlations between investigated variables, visual acuity and IOP changes at 3 months after phacoemulsification were found. Phacoemulsification of visually non-significant cataract appears to be a safe and effective technique for managing chronic ocular hypotony with deep anterior chamber due to over-filtering blebs.

  4. Intraocular pressure 1 year after vitrectomy in eyes without a history of glaucoma or ocular hypertension

    Directory of Open Access Journals (Sweden)

    Fang Y

    2017-11-01

    Full Text Available Yuan Fang,1 Qingqing Long,1 Xiaoqian Wang,2 Rui Jiang,1 Xinghuai Sun1,3–5 1Department of Ophthalmology and Visual Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, 2Department of Ophthalmology, Jiangyin Bright Eye Hospital, Jiangyin, Jiangsu, 3State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, 4Key Laboratory of Myopia, NHFPC (Fudan University, 5Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, People’s Republic of China Objective: The aim of this study was to investigate the incidence, risk factors, and treatment of elevated intraocular pressure (IOP 1 year after vitrectomy in eyes without a history of glaucoma or ocular hypertension.Patients and methods: This retrospective study comprised 256 eyes from 256 consecutive patients without a history of glaucoma or ocular hypertension who underwent vitrectomy and were followed up for 1 year. The incidence of elevated IOP at 1 year after vitrectomy was calculated. We compared the characteristics of patients with or without elevated IOP to identify possible risk factors for elevated IOP. The treatments used to control IOP were recorded and analyzed.Results: A total of 50 patients (19.5% had elevated IOP after vitrectomy at the 1-year follow-up. Tamponade was a significant risk factor for elevated IOP (P<0.05. The cumulative rates of elevated IOP in eyes with air, balanced salt solution, sulfur hexafluoride, perfluoropropane (C3F8, and silicone oil as the tamponade were 0, 10.8%, 5.9%, 19.8%, and 28.4%, respectively (P<0.05. About 68% of cases of elevated IOP occurred within 1 month after vitrectomy. At 1 year after vitrectomy, 29 patients (58.0% had stopped their IOP-lowering drugs and 21 (42.0% patients were continuing these drugs. About 65% of ocular hypertension patients who received silicone oil tamponade had not stopped IOP-lowering drugs

  5. Fluctuation of intraocular pressure in glaucoma patients before and after trabeculectomy with mitomycin C.

    Directory of Open Access Journals (Sweden)

    Joanna Wasielica-Poslednik

    Full Text Available Intraocular pressure (IOP fluctuation is considered as a risk factor for glaucoma progression. We investigated IOP values and IOP fluctuation before and after trabeculectomy (TE with mitomycin C (MMC measured by 48-hour diurnal-nocturnal-IOP-profiles (DNP.Pre- and postoperative DNPs of 92 eyes undergoing primary TE with MMC were analysed. Each 48-hour IOP-profile involved 10 IOP measurements (8:00 a.m., 2:00 p.m., 6:00 p.m., and 9:00 p.m. in sitting and at 00:00 in supine position. The "preoperative DNP" was performed a few weeks before TE. The "postoperative DNP" was performed at least six months (range: 6 months-2 years after TE. Mean IOP values and IOP fluctuations were calculated.After TE with MMC mean IOP was reduced from 16.94±3.83 to 11.26±3.77 mmHg at daytime and from 18.17±4.26 to 11.76±3.90 mmHg at night. At daytime mean IOP-fluctuation decreased from 8.61±4.19 to 4.92±2.52 mmHg, at night from 3.15±2.95 to 1.99±1.82 mmHg. Mean IOP was lower on the second day of the preoperative DNP. This effect was not present in the postoperative DNP. Preoperatively, IOP was controlled in all eyes with a mean of 3.22±0.94 antiglaucomatous agents. Postoperatively, IOP≤15 mmHg was achieved in 71.7%, IOP≤18 mmHg in 77.1% and a decrease in IOP of >30% in 47.8% without antiglaucomatous therapy. Postoperatively, pseudophakia was associated by a higher mean IOP-fluctuation compared to the phakic eyes.TE with MMC significantly reduces both mean IOP-values and IOP- fluctuations at day and night at least 6 months postoperatively. The effect of TE on the IOP fluctuation was less pronounced in pseudophakic eyes.

  6. Posterior fixation keratoprostheses and mechanical biocompatibility: determination of critical intraocular pressure causing aqueous humor leak and/or keratoprosthesis extrusion

    Science.gov (United States)

    Tahi, Hassan; Duchesne, Bernard; Parel, Jean-Marie A.; Nose, Izuru; Denham, David B.; Villain, Franck L.; Lacombe, Emmanuel

    1997-05-01

    The effect of increased intraocular pressure (IOP) in human cadaver eyes implanted with posterior fixation keratoprosthesis was evaluated. Experiments were carried out with six fresh pairs of human cadaver eyes. One eye of each pair was implanted with a PCL-5 keratoprosthesis (8.60 mm diameter with an optic of 5.60 nm diameter) and the contralateral eye was used as a control. The keratoprosthesis was inserted through a 6 mm diameter opening trephined in the cornea. The resistance of the implanted eye to pressure on `aqueous humor' leak and/or keratoprosthesis extrusion was tested by infusing water at a constant flow of 60 mmHg/second into the anterior chamber. IOP variations were recorded with a transducer connected to a computer. IOP could be increased up to 1520 to 2324 mmHg before aqueous humor leaks occurred. Leaks were always located at the keratoprosthesis-cornea interface. No prosthesis extrusion was observed. Implanted eyes that did not leak aqueous and control eyes tore at the sclera. All posterior fixation keratoprostheses implanted eyes resisted more than 100 times the normal physiological intraocular pressure and on this standpoint is safe. Additional experiments were needed to assess the influence of suture fixation and wound healing in an animal model.

  7. Circadian rhythms in blood pressure in free-ranging three-toed sloths (Bradypus variegatus

    Directory of Open Access Journals (Sweden)

    Duarte D.P.F.

    2003-01-01

    Full Text Available Blood pressure (BP profiles were monitored in nine free-ranging sloths (Bradypus variegatus by coupling one common carotid artery to a BP telemetry transmitter. Animals moved freely in an isolated and temperature-controlled room (24ºC with 12/12-h artificial light-dark cycles and behaviors were observed during resting, eating and moving. Systolic (SBP and diastolic (DBP blood pressures were sampled for 1 min every 15 min for 24 h. BP rhythm over 24 h was analyzed by the cosinor method and the mesor, amplitude, acrophase and percent rhythm were calculated. A total of 764 measurements were made in the light cycle and 721 in the dark cycle. Twenty-four-hour values (mean ± SD were obtained for SBP (121 ± 22 mmHg, DBP (86 ± 17 mmHg, mean BP (MBP, 98 ± 18 mmHg and heart rate (73 ± 16 bpm. The SBP, DBP and MBP were significantly higher (unpaired Student t-test during the light period (125 ± 21, 88 ± 15 and 100 ± 17 mmHg, respectively than during the dark period (120 ± 21, 85 ± 17 and 97 ± 17 mmHg, respectively and the acrophase occurred between 16:00 and 17:45 h. This circadian variation is similar to that observed in cats, dogs and marmosets. The BP decreased during "behavioral sleep" (MBP down from 110 ± 19 to 90 ± 19 mmHg at 21:00 to 8:00 h. Both feeding and moving induced an increase in MBP (96 ± 17 to 119 ± 17 mmHg at 17:00 h and 97 ± 19 to 105 ± 12 mmHg at 15:00 h, respectively. The results show that conscious sloths present biphasic circadian fluctuations in BP levels, which are higher during the light period and are mainly synchronized with feeding.

  8. Combined ab interno trabeculotomy and lens extraction: a novel management option for combined uveitic and chronic narrow angle raised intraocular pressure.

    Science.gov (United States)

    Lin, Siying; Gupta, Bhaskar; Rossiter, Jonathan

    2016-02-01

    Minimally invasive glaucoma surgery is a developing area that has the potential to replace traditional glaucoma surgery, with its known risk profile, but at present there are no randomised controlled data to validate its use. We report on a case where sequential bilateral combined ab interno trabeculotomy and lens extraction surgery was performed on a 45-year-old woman with combined uveitic and chronic narrow angle raised intraocular pressure. Maximal medical management alone could not control the intraocular pressure. At 12-month follow-up, the patient had achieved stable intraocular pressure in both eyes on a combination of topical ocular antiglaucomatous and steroid therapies. This case demonstrates the effectiveness of trabecular meshwork ablation via ab interno trabeculotomy in a case of complex mixed mechanism glaucoma. 2016 BMJ Publishing Group Ltd.

  9. Comparison of intraocular pressure andvault after implantation of implantable collamer lens with and without a central hole.

    Science.gov (United States)

    Chen, Haiting; Niu, Guangzeng; Fan, Yuxiang; Ma, Jingxue

    2016-11-16

    The Implantable Collamer Lens (ICL) has been used widely for refractive errors, We performed this prospective randomized comparative study to compare postoperative intraocular pressure (IOP) and vaults of the eyes implanted with conventional ICL and central hole ICL. This study evaluated 44 eyes of 22 patients who underwent central hole ICL implantation in one eye and conventional ICL implantation in the other eye by randomization assignment. noncontact intraocular pressure were performed on 6 h, 1 day, 3 days, 1 week, 2 weeks, 1 month, 3 months and 6 months, while ICL vaults were measured on 1 day, 1 week, 1 month and 6 months. The IOP of both eyeswithcentral hole and conventional ICLrosetemporarily during the first month after surgeries, especially on 1 day and 2 weeks points postoperatively. The IOP ofeyes with central hole ICL was higher than that of conventionl ICL. The vaults ofeyes with central hole and conventional ICL decreased slightly with time but did not significantly affect the postoperative IOP. Despite the sensitivity of viscoelastic agents or inflammation, this newly developed central hole ICL implantation appears to be equivalent in safty and effcacy to conventional ICL implantation for the correction of ametropia. Current Controlled Trials ChiCTR-INR-16008896 . Retrospectively registered 24 July 2016.

  10. Study of the effect of distance and misalignment between magnetically coupled coils for wireless power transfer in intraocular pressure measurement.

    Science.gov (United States)

    Rendon-Nava, Adrian E; Díaz-Méndez, J Alejandro; Nino-de-Rivera, Luis; Calleja-Arriaga, Wilfrido; Gil-Carrasco, Felix; Díaz-Alonso, Daniela

    2014-01-01

    An analysis of the effect of distance and alignment between two magnetically coupled coils for wireless power transfer in intraocular pressure measurement is presented. For measurement purposes, a system was fabricated consisting of an external device, which is a Maxwell-Wien bridge circuit variation, in charge of transferring energy to a biomedical implant and reading data from it. The biomedical implant is an RLC tank circuit, encapsulated by a polyimide coating. Power transfer was done by magnetic induction coupling method, by placing one of the inductors of the Maxwell-Wien bridge circuit and the inductor of the implant in close proximity. The Maxwell-Wien bridge circuit was biased with a 10 MHz sinusoidal signal. The analysis presented in this paper proves that wireless transmission of power for intraocular pressure measurement is feasible with the measurement system proposed. In order to have a proper inductive coupling link, special care must be taken when placing the two coils in proximity to avoid misalignment between them.

  11. Intraocular pressure 3 to 4 hours and 20 hours after cataract surgery with and without ab interno trabeculectomy.

    Science.gov (United States)

    Weiner, Yotam; Severson, Melissa L; Weiner, Asher

    2015-10-01

    To evaluate intraocular pressure (IOP) immediately after cataract surgery with or without ab interno trabeculectomy (Trabectome) and whether trabeculectomy-related hyphema increases the risk for IOP spikes. Private glaucoma practice. Retrospective interventional nonrandomized comparative chart review. Intraocular pressure was measured 3 to 4 hours and 20 hours postoperatively. The combined group comprised 73 eyes of 73 patients and the cataract-only group, 75 eyes of 75 patients. The mean preoperative IOP was 15.8 mm Hg ± 3.6 (SD) and 14.9 ± 3.0 mm Hg, respectively (P = .09). In the combined group, the IOP decrease was significant at 3 to 4 hours (P = .0003) and 20 hours (P = .0007). In the cataract-only group, the IOP increased significantly (P interno trabeculectomy and cataract surgery reduced short-term postoperative IOP and the incidence of IOP spikes despite the common hyphema. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  12. Study of the Effect of Distance and Misalignment between Magnetically Coupled Coils for Wireless Power Transfer in Intraocular Pressure Measurement

    Directory of Open Access Journals (Sweden)

    Adrian E. Rendon-Nava

    2014-01-01

    Full Text Available An analysis of the effect of distance and alignment between two magnetically coupled coils for wireless power transfer in intraocular pressure measurement is presented. For measurement purposes, a system was fabricated consisting of an external device, which is a Maxwell-Wien bridge circuit variation, in charge of transferring energy to a biomedical implant and reading data from it. The biomedical implant is an RLC tank circuit, encapsulated by a polyimide coating. Power transfer was done by magnetic induction coupling method, by placing one of the inductors of the Maxwell-Wien bridge circuit and the inductor of the implant in close proximity. The Maxwell-Wien bridge circuit was biased with a 10 MHz sinusoidal signal. The analysis presented in this paper proves that wireless transmission of power for intraocular pressure measurement is feasible with the measurement system proposed. In order to have a proper inductive coupling link, special care must be taken when placing the two coils in proximity to avoid misalignment between them.

  13. Altering the way the optic nerve head responds to intraocular pressure-a potential approach to glaucoma therapy.

    Science.gov (United States)

    Strouthidis, Nicholas G; Girard, Michael J A

    2013-02-01

    Over the past decade, engineering principles have been used to explain why a mechanical load, intraocular pressure, can lead to the development of glaucomatous optic neuropathy. This has led to the 'biomechanical theory' of glaucoma, which posits that the behavior of optic nerve head connective tissues (specifically within the peripapillary sclera and lamina cribrosa) in response to intraocular pressure (regardless of its magnitude) can directly and indirectly influence the physiology and pathophysiology of the optic nerve head. Given that the biomechanics of the sclera and lamina cribrosa probably influence retinal ganglion cell loss in glaucoma, the idea that altering biomechanical behavior might be protective against glaucoma is an appealing notion. There is some evidence to suggest that stiffening the peripapillary sclera may be protective against the development of glaucoma in an animal model. It is technically possible to stiffen the sclera in vivo using collagen cross-linking techniques already applied in vivo to the cornea in the treatment of keratoconus. It has yet to be established whether scleral cross-linking is safe in humans and that it confers anything more than a theoretical advantage in terms of reducing the risk of glaucomatous damage. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  14. Exercise-induced albuminuria and circadian blood pressure abnormalities in type 2 diabetes

    Science.gov (United States)

    Tankeu, Aurel T; Kaze, François Folefack; Noubiap, Jean Jacques; Chelo, David; Dehayem, Mesmin Yefou; Sobngwi, Eugene

    2017-01-01

    AIM To investigate the relationship between circadian variations in blood pressure (BP) and albuminuria at rest, and during exercise in non-hypertensive type 2 diabetes (T2D) patients. METHODS We conducted a cross-sectional study in well controlled T2D patients, non-hypertensive, without clinical proteinuria and normal creatinine clearance. In each participant, we recorded the BP using ambulatory blood pressure monitoring (ABPM) for 24-h, and albuminuria at rest and after a standardized treadmill exercise. RESULTS We enrolled 27 type 2 patients with a median age of 52; and a mean duration of diabetes and HbA1c of 3.6 ± 0.8 years and 6.3% ± 0.5% respectively. Using a 24-h ABPM, we recorded a mean diurnal systolic blood pressure (SBP) of 128 ± 17 mmHg vs nocturnal of 123 ± 19 mmHg (P = 0.004), and mean diurnal diastolic blood pressure (DBP) of 83 ± 11 mmHg vs nocturnal 78 ± 14 mmHg (P = 0.002). There was a significant difference between albuminuria at rest [median = 23 mg, interquartile range (IQR) = 10-51] and after exercise (median = 35 mg, IQR = 23-80, P albuminuria had an increase in nocturnal BP values on all three components (128 mmHg vs 110 mmHg, P = 0.03 for SBP; 83 mmHg vs 66 mmHg, P = 0.04; 106 vs 83, P = 0.02 for mean arterial pressure), as well as albuminuric patients at rest. Moreover, exercise induced albuminuria detect a less increase in nocturnal DBP (83 vs 86, P = 0.03) than resting albuminuria. CONCLUSION Exercise induced albuminuria is associated with an increase in nocturnal BP values in T2D patients. PMID:28729969

  15. Correlation between intraocular pressure and the biometric structure of the anterior chamber in patients of chronic renal failure with hemodialysis

    Directory of Open Access Journals (Sweden)

    Zhi-Ying Yu

    2017-02-01

    Full Text Available AIM: To investigate the correlation between intraocular pressure(IOPchanges pre- and post-hemodialysis(HDand the biometric structure of the anterior chamber in patients of chronic renal failure. METHODS: Fifty-two patients(take right eye as study onewith hemodialysis that were diagnosed with chronic renal failure by nephrology in our hospital from January 2015 to December 2015 were collected. Fifty-two eyes were divided into four groups based on Shaffer classification combined with ultrasound biomicroscopy(UBMand gonioscopy manifestations: wide angle group, narrow angle group, extremely narrow group and close angle group. Venous blood was collected to get plasma colloid osmotic pressure before HD and within 60s after HD. IOP was measured with rebound intraocular pressure gauge in a supine positon approximately 30min before starting HD, 2h after HD begin and approximately 30min after HD ending. Approximately 30min before and after HD, central corneal thickness was measured with corneal endothelial cell counter, central anterior chamber depth and lens thickness were taken by A scan, angle opening distance, trabecular iris angle, iris thickness and ciliary body thickness were measured by UBM. RESULTS: Plasma osmotic pressure reduced after HD, the difference was statistically significant(t=3.04, PF=41.69, PPPF=6.44, PPt=2.61, PCONCLUSION: The influence of hemodialysis on IOP is related to the biometric structure of the anterior chamber. And extremely narrow angle is risk factor of elevated IOP during hemodialysis, narrow angle may be a risk factor. While patients with wide angle is relatively safe. We suggest to take ocular examination as early as possible for patients with hemodialysis, and focus on patients with narrow angle.

  16. Mirtogenol® potentiates latanoprost in lowering intraocular pressure and improves ocular blood flow in asymptomatic subjects

    Directory of Open Access Journals (Sweden)

    Robert D Steigerwalt Jr

    2010-05-01

    Full Text Available Robert D Steigerwalt Jr1, Gianni Belcaro1, Paolo Morazzoni2, Ezio Bombardelli2, Carolina Burki3, Frank Schönlau4 1Department of Biomedical Sciences, University of Chieti-Pescara, San Valentino, Italy; 2Indena S.p.A. Scientific Department, Milan, Italy; 3Horphag Research (UK Ltd., Geneva, Switzerland; 4Horphag Research (UK Ltd. South Kensington, London UKPurpose: The dietary supplement Mirtogenol® was previously shown to lower elevated intraocular pressure (IOP. We here present the effects of this supplement on IOP in comparison as well as in combination with latanoprost eye drops. Methods: Seventy-nine patients with asymptomatic ocular hypertension were randomly assigned to three groups receiving either the supplement, or latanoprost eye drops, or both in combination. Intraocular pressure and retinal blood flow were investigated in monthly intervals over 24 weeks.Results: Mirtogenol alone lowered IOP from baseline 38.1 to 29.0 mmHg after 16 weeks, with little further improvement during the following eight weeks. Latanoprost rapidly lowered IOP from baseline 37.7 to 27.2 mmHg within four weeks, without further effects thereafter. The combination of the supplement and latanoprost lowered IOP from 38.0 to 27.3 mmHg after four weeks, and further decreased IOP to 24.2 mmHg after six weeks. After 24 weeks IOP with the combination treatment (23.0 mmHg was significantly lower than with latanoprost alone (27.2 mmHg. Mirtogenol and latanoprost individually showed comparable effects for gradually increasing central artery blood flow with treatment duration. Combination treatment showed higher systolic blood flow velocity throughout the trial period. The diastolic blood flow velocity gradually increased with treatment duration in all three groups. From twelve weeks onwards, the diastolic component with combination treatment was higher than with individual treatments.Conclusions: Mirtogenol lowered elevated IOP in patients almost as effectively as

  17. [Effects of reading, exercise and exercise combined with reading on intraocular pressure for patients sustaining primary glaucoma (open angle) or ocular hypertension, both clinically controlled with topic medication].

    Science.gov (United States)

    Medina, Alice Maria Corrêa; Lima, Núbia Vanessa dos Anjos; Santos, Regina Cândida Ribeiro dos; Pereira, Marco César Araújo; Santos, Procópio Miguel dos

    2007-01-01

    To check intraocular pressure (IOP) in individuals using prostaglandin, prostamide or beta-blocker analogues, who sustain either primary open angle glaucoma or ocular hypertension after reading, exercise or exercise combined with reading. 40 individuals (79 eyes), subdivided in to five groups: G1 (with arterial hypertension and either glaucoma or ocular hypertension, all users of prostaglandin or prostamide analogues); G2 (with arterial hypertension and either glaucoma or ocular hypertension, all users of beta-blockers); G3 (not sustaining arterial hypertension but suffering from either glaucoma or ocular hypertension, all users of prostaglandin or prostamide analogues); G4 (not sustaining arterial hypertension but suffering from either glaucoma or ocular hypertension, all users of beta-blockers) and G5 (not sustaining arterial hypertension and also not suffering from either glaucoma or ocular hypertension) had their intraocular pressure checked before and after undergoing reading, exercise, and exercise combined with reading. Each type of test was conducted in a different day, always in the afternoon. No significant statistical difference has been noticed between the initial and final intraocular pressure mean in the different groups, when reading, performing exercises or exercises combined with reading. To read and to work out--either separately or jointly--does not pose an aggravating factor to the intraocular pressure of patients with primary open glaucoma or ocular hypertension, using prostaglandin, prostamide or beta-blocker analogues.

  18. New insights into the genetics of primary open-angle glaucoma based on meta-analyses of intraocular pressure and optic disc characteristics.

    NARCIS (Netherlands)

    Springelkamp, H. (Henriët); Iglesias, A.I. (Adriana); Mishra, A. (Aniket); Höhn, R. (René); Wojciechowski, R. (Robert); Khawaja, A.P. (Anthony); Nag, A. (Abhishek); Wang, Y.X. (Ya Xing); Wang, J.J. (Jie Jin); Cuellar-Partida, G. (Gabriel); Gibson, J. (Jane); Cooke Bailey, J.N. (Jessica); Vithana, E.N. (Eranga); Gharahkhani, P. (Puya); Boutin, T. (Thibaud); Ramdas, W.D. (Wishal); Zeller, T. (Tanja); Luben, R.N. (Robert); Yonova-Doing, E. (Ekaterina); Viswanathan, A.C. (Ananth); Yazar, S. (Seyhan); Cree, A.J. (Angela); Haines, J.L. (Jonathan); Koh, J.Y. (Jia Yu); Souzeau, E. (Emmanuelle); Wilson, J.F. (James); Amin, N. (Najaf); Müller, C. (Christian); Venturini, C. (Cristina); Kearns, L.S. (Lisa); Hee Kang, J. (Jae); Consortium, N. (Neighborhood); Tham, Y.C. (Yih Chung); Zhou, T. (Tiger); van Leeuwen, E.M. (Elisabeth); Nickels, S. (Stefan); Sanfilippo, P. (Paul); Liao, J. (Jiemin); Linde, H.V. (Herma van der); Zhao, W. (Wanting); van Koolwijk, L.M. (Leonieke); Zheng, L. (Li); Rivadeneira, F. (Fernando); Baskaran, M. (Mani); van der Lee, S.J. (Sven); Perera, S. (Shamira); de Jong, P.T. (Paulus); Oostra, B.A. (Ben); Uitterlinden, A.G. (André); Fan, Q. (Qiao); Hofman, A. (Albert); Shyong Tai, E. (E-); Vingerling, J.R. (Johannes); Sim, X. (Xueling); Wolfs, R.C. (Roger); Teo, Y.Y. (Yik Ying); Lemij, H.G. (Hans); Khor, C.C. (Chiea Chuen); Willemsen, R. (Rob); Lackner, K.J. (Karl); Aung, T. (Tin); Jansonius, N.M. (Nomdo); Montgomery, G. (Grant); Wild, P.S. (Philipp); Young, T.L. (Terri); Burdon, K.P. (Kathryn); Hysi, P.G. (Pirro); Pasquale, L.R. (Louis); Wong, T.Y. (Tien Yin); Klaver, C.C. (Caroline); Hewitt, A.W. (Alex); Jonas, J.B. (Jost); Mitchell, P. (Paul); Lotery, A.J. (Andrew); Foster, P.J. (Paul); Vitart, V. (Veronique); Pfeiffer, N. (Norbert); Craig, J.E. (Jamie); Mackey, D.A. (David); Hammond, C.J. (Christopher); Wiggs, J.L. (Janey); Cheng, C.Y. (Ching-Yu); van Duijn, C.M. (Cornelia); MacGregor, S. (Stuart)

    2017-01-01

    textabstractPrimary open-angle glaucoma (POAG), the most common optic neuropathy, is a heritable disease. Siblings of POAG cases have a ten-fold increase risk of developing the disease. Intraocular pressure (IOP) and optic nerve head characteristics are used clinically to predict POAG risk. We

  19. New insights into the genetics of primary open-angle glaucoma based on meta-analyses of intraocular pressure and optic disc characteristics

    NARCIS (Netherlands)

    Springelkamp, Henriët; Iglesias, Adriana I; Mishra, Aniket; Höhn, René; Wojciechowski, Robert; Khawaja, Anthony P; Nag, Abhishek; Wang, Ya Xing; Wang, Jie Jin; Cuellar-Partida, Gabriel; Gibson, Jane; Cooke Bailey, Jessica N; Vithana, Eranga N; Gharahkhani, Puya; Boutin, Thibaud; Ramdas, Wishal D; Zeller, Tanja; Luben, Robert N; Yonova-Doing, Ekaterina; Viswanathan, Ananth C; Yazar, Seyhan; Cree, Angela J; Haines, Jonathan L; Koh, Jia Yu; Souzeau, Emmanuelle; Wilson, James F; Amin, Najaf; Müller, Christian; Venturini, Cristina; Kearns, Lisa S; Hee Kang, Jae; Consortium, Neighborhood; Tham, Yih Chung; Zhou, Tiger; van Leeuwen, Elisabeth M; Nickels, Stefan; Sanfilippo, Paul; Liao, Jiemin; Linde, Herma van der; Zhao, Wanting; van Koolwijk, Leonieke M E; Zheng, Li; Rivadeneira, Fernando; Baskaran, Mani; van der Lee, Sven J; Perera, Shamira; de Jong, Paulus T V M; Oostra, Ben A; Uitterlinden, André G; Fan, Qiao; Hofman, Albert; Shyong Tai, E-; Vingerling, Johannes R; Sim, Xueling; Wolfs, Roger C W; Teo, Yik Ying; Lemij, Hans G; Khor, Chiea Chuen; Willemsen, Rob; Lackner, Karl J; Aung, Tin; Jansonius, Nomdo M; Montgomery, Grant; Wild, Philipp S; Young, Terri L; Burdon, Kathryn P; Hysi, Pirro G; Pasquale, Louis R; Wong, Tien Yin; Klaver, Caroline C W; Hewitt, Alex W; Jonas, Jost B; Mitchell, Paul; Lotery, Andrew J; Foster, Paul J; Vitart, Veronique; Pfeiffer, Norbert; Craig, Jamie E; Mackey, David A; Hammond, Christopher J; Wiggs, Janey L; Cheng, Ching-Yu; van Duijn, Cornelia M; MacGregor, Stuart

    2017-01-01

    Primary open-angle glaucoma (POAG), the most common optic neuropathy, is a heritable disease. Siblings of POAG cases have a ten-fold increase risk of developing the disease. Intraocular pressure (IOP) and optic nerve head characteristics are used clinically to predict POAG risk. We conducted a

  20. New insights into the genetics of primary open-angle glaucoma based on meta-analyses of intraocular pressure and optic disc characteristics

    NARCIS (Netherlands)

    Springelkamp, Henriet; Iglesias, Adriana I; Mishra, Aniket; Hoehn, Rene; Wojciechowski, Robert; Khawaja, Anthony P.; Nag, Abhishek; Wang, Ya; Wang, Jie Jin; Cuellar-Partida, Gabriel; Gibson, Jane; Bailey, Jessica N Cooke; Vithana, Eranga N.; Gharahkhani, Puya; Boutin, Thibaud S.; Ramdas, Wishal D.; Zeller, Tanja; Luben, Robert N.; Yonova-Doing, Ekaterina; Viswanathan, Ananth C.; Yazar, Seyhan; Cree, Angela J.; Haines, Jonathan L.; Koh, Jia Yu; Souzeau, Emmanuelle; Wilson, James F.; Amin, Najaf; Mueller, Christian; Venturini, Cristina; Kearns, Lisa S.; Kang, Jae Hee; Tham, Yih Chung; Zhou, Tiger; van Leeuwen, Elisabeth M.; Nickels, Stefan; Sanfilippo, Paul G.; Liao, Jiemin; van der Linde, Herma C; Zhao, Wanting; van Koolwijk, Leonieke M. E.; Zheng, Li; Rivadeneira, Fernando; Baskaran, Mani; van der Lee, Sven J; Perera, Shamira; de Jong, Paulus T. V. M.; Oostra, Ben A.; Uitterlinden, Andre G.; Fan, Qiao; Hofman, Albert; Tai, E. Shyong; Vingerling, Johannes R.; Sim, Xueling; Wolfs, Roger C. W.; Teo, Yik-Ying; Lemij, Hans G.; Khor, Chiea Chuen; Willemsen, Rob; Lackner, Karl J.; Aung, Tin; Jansonius, Nomdo M.; Montgomery, Grant M.; Wild, Philipp S.; Young, Terri L.; Burdon, Kathryn P; Hysi, Pirro G.; Pasquale, Louis R; Wong, Tien-Yin; Klaver, Caroline C. W.; Hewitt, Alex W.; Jonas, Jost B; Mitchell, Paul; Lotery, Andrew J.; Foster, Paul J.; Vitart, Veronique; Pfeiffer, Norbert; Craig, Jamie E; Mackey, David A.; Hammond, Christopher J.; Wiggs, Janey L; Cheng, Ching-Yu; Duijn, Cornelia Mvan; Macgregor, Stuart

    2017-01-01

    Primary open-angle glaucoma (POAG), the most common optic neuropathy, is a heritable disease. Siblings of POAG cases have a ten-fold increased risk of developing the disease. Intraocular pressure (IOP) and optic nerve head characteristics are used clinically to predict POAG risk. We conducted a

  1. Applanation optical coherence elastography: noncontact measurement of intraocular pressure, corneal biomechanical properties, and corneal geometry with a single instrument

    Science.gov (United States)

    Singh, Manmohan; Han, Zhaolong; Nair, Achuth; Schill, Alexander; Twa, Michael D.; Larin, Kirill V.

    2017-02-01

    Current clinical tools provide critical information about ocular health such as intraocular pressure (IOP). However, they lack the ability to quantify tissue material properties, which are potent markers for ocular tissue health and integrity. We describe a single instrument to measure the eye-globe IOP, quantify corneal biomechanical properties, and measure corneal geometry with a technique termed applanation optical coherence elastography (Appl-OCE). An ultrafast OCT system enabled visualization of corneal dynamics during noncontact applanation tonometry and direct measurement of micro air-pulse induced elastic wave propagation. Our preliminary results show that the proposed Appl-OCE system can be used to quantify IOP, corneal biomechanical properties, and corneal geometry, which builds a solid foundation for a unique device that can provide a more complete picture of ocular health.

  2. Effects of a water-loading test on intraocular pressure and corneal hysteresis in young healthy subjects.

    Science.gov (United States)

    Ulaş, Fatih; Balbaba, Mehmet; Celebi, Serdal

    2014-02-01

    To evaluate the influence of a water-loading test on corneal compensated intraocular pressure (IOPcc) and corneal hysteresis (CH) in young healthy subjects. Forty healthy adult subjects (20 female and 20 male), with a mean age of 27.55±2.57 years (range, 24 to 35 y), participated in this prospective study. IOPcc and CH were measured for 1 eye from each participant with an Ocular Response Analyser. These measurements were taken before and 10, 20, and 30 minutes after water loading. Thirty-seven right and 3 left eyes of the 40 subjects fulfilled the study's inclusion criteria. A statistically significant increase in IOPcc was observed between 0 and 10 minutes (P=0.002) and a significant decrease between 10 and 30 minutes (Pcorneal biomechanical properties.

  3. Influence on intraocular pressure of the postural change and daily activities in the early morning in suspected glaucoma patients

    Directory of Open Access Journals (Sweden)

    Ting Chen

    2014-05-01

    Full Text Available AIM:To evaluate the influence on intraocular pressure(IOPof the postural change and daily activities in the early morning in suspected glaucoma patients.METHODS:The supine and sitting IOP were measured and analyzed on 51 suspected glaucoma patients(100 eyeswith Icare rebound tonometer before and after getting up and daily activities in the early morning. RESULTS: The mean of sitting IOP of 51 patients was 17.12±4.53mmHg, which was significantly lower than the mean of supine IOP(19.14±5.51mmHg. The mean of IOP before and after daily activity of 51 patients were 17.12±4.53mmHg and 14.44±3.90mmHg respectively, which showed significantly difference. CONCLUSION:Postural change and daily activities can result in significant changes of IOP in suspected glaucoma patients.

  4. Assessment of the biomechanical properties of porcine cornea after UV cross-linking at different intraocular pressures

    Science.gov (United States)

    Li, Jiasong; Singh, Manmohan; Vantipalli, Srilatha; Han, Zhaolong; Liu, Chih-Hao; Twa, Michael D.; Larin, Kirill V.

    2015-03-01

    In this study we demonstrate the use of phase-stabilized swept-source optical coherence elastography (PhS-SSOCE) to assess the biomechanical properties of porcine corneas before and after collagen cross-linking (CXL) at different intraocular pressures by measuring the velocity of an air-pulse induced elastic wave and recovery process rate of an air-pulse induced deformation. Young's moduli were estimated by two different methods: the shear wave equation and a newly developed elasticity reconstruction model. The results show that the corneas became stiffer after the CXL treatment, as evidenced by the increased elastic wave velocity and recovery process rate and greater Young's modulus. This non-contact and noninvasive measurement technique utilizes minimal force for excitation (deformation less than 10 μm in amplitude) of the tissue. Thus, it can be potentially used to study the biomechanical properties of ocular and other delicate tissues.

  5. 24-hour intraocular pressure fluctuation monitoring using an ocular telemetry Sensor: tolerability and functionality in healthy subjects.

    Science.gov (United States)

    De Smedt, Stefan; Mermoud, André; Schnyder, Corinne

    2012-01-01

    To evaluate the tolerability, comfort, and reliability of the signal transmission of an ocular Sensor used for 24-hour intraocular pressure fluctuation monitoring in humans. In this uncontrolled open trial involving 10 healthy volunteers, an 8.7-mm radius prototype ocular telemetry Sensor (SENSIMED Triggerfish, Lausanne, Switzerland) and an orbital bandage containing a loop antenna were applied and connected to a portable recorder after full eye examination. Best-corrected visual acuity and position, surface wetting ability, and mobility of the Sensor were assessed after 5 and 30 minutes, 4, 12, and 24 hours. Subjective wearing comfort was scored and activities documented in a logbook. After Sensor removal, a full eye examination was repeated and the recorded signal analyzed. The comfort score was high and did not fluctuate significantly over time. The mobility of the Sensor was limited across follow-up visits and its surface wetting ability remained good. Best-corrected visual acuity was significantly reduced during Sensor wear and immediately after its removal (from 1.07 before, to 0.85 after, P value 0.008). Three subjects developed a mild, transient corneal abrasion. In all but 1 participant, we obtained usable data of a telemetric signal recording with sufficient sensitivity to depict ocular pulsation. This 24-hour trial has encouraging results on the tolerability and functionality of the ocular telemetric Sensor for intraocular pressure fluctuation monitoring. Further studies with different Sensor radii conducted on a larger study population are needed to improve comfort, precision, and interpretation of the telemetric signal.

  6. Intraocular pressure changes in a Nigerian population--effects of tracheal tube and laryngeal mask airway insertion and removal.

    Science.gov (United States)

    Igboko, J O; Desalu, I; Akinsola, F B; Kushimo, O T

    2009-06-01

    Laryngoscopy and tracheal intubation lead to acute elevation in intraocular pressure (IOP); the ocular hypertensive response. The Laryngeal mask airway prevents sudden surges in IOP. We compared IOP changes to the insertion and removal of the Laryngeal mask airway (LMA) and the endotracheal tube (ETT). Seventy ASA I and II patients aged 18 to 60 years at the Lagos University Teaching Hospital between January and December 2003 were randomly allocated to receive either an LMA or ETT for airway management. Anaesthesia was induced with propofol and atracurium. Intraocular pressure was measured by applanation tonometry post induction (baseline) and prior to removal (pre-extubation), after insertion or removal (0 minute), at 1,2,3,5 and 10 minutes after insertion or removal. Insertion of the airway device caused an immediate rise in IOP of 4.6% in the LMA group (from 13.1 +/- 2.4 to 13.7 +/- 2.4 mmHg) and 49.2 in the ETT group (from 12.0 +/- 2.5 to 17.9 +/- 4.0 mmHg) (p<0.001). Removal of the airway device caused an immediate rise in IOP of 14.6 in the LMA group (from 11.26 +/- 2.4 to 12.9 +/-2.4 mmHg) and 50.3 in the ETT group (from 11.37 +/- 2.0 to 17.1 +/- 3.3 mmHg) (p<0.001). IOP thereafter declined towards baseline in both groups. Cardiovascular responses accompanied IOP changes. The mean insertion time was 39.8 +/- 9.1 seconds (ETT) vs 31.5 +/- 4.4 seconds (LMA). (p<0.001) Cough (17.1) and mild laryngeal spasm (2.9) occurred in the ETT group only following removal. The LMA produced better IOP stability following its insertion and removal compared to the tracheal tube.

  7. Corneal hysteresis, corneal resistance factor, and intraocular pressure measurement in patients with scleroderma using the reichert ocular response analyzer.

    Science.gov (United States)

    Emre, Sinan; Kayikçioğlu, Ozcan; Ateş, Halil; Cinar, Esat; Inceoğlu, Nehir; Yargucu, Figen; Pirildar, Timur; Oksel, Fahrettin

    2010-06-01

    The Reichert ocular response analyzer (ORA) measures corneal biomechanical properties in vivo by monitoring and analyzing the corneal behavior when its structure is submitted to a force induced by an air jet. This study was designed to examine corneal biomechanical properties and intraocular pressure in patients with systemic sclerosis (SSc) and to compare with control eyes. ORA measurements were performed on the right eyes of 29 patients with SSc (group 1) and 29 healthy people who served as the control group (group 2). Corneal hysteresis, corneal resistance factor (CRF), and intraocular pressure [Goldmann correlated (IOPg) and corneal compensated] were recorded with ORA. Mean age of patients with SSc and control groups were 51.7 +/- 11.1 and 50.3 +/- 10.8 years, respectively. Mean (+/-SD) of the corneal hysteresis and CRF readings were 9.8 +/- 1.7 versus 9.5 +/- 1.2 mm Hg (P > 0.05) and 10.0 +/- 1.5 versus 9.2 +/- 1.4 mm Hg (P corneal-compensated recordings were 15.9 +/- 2.5 versus 14.1 +/- 2.4 mm Hg (P 0.05), in groups 1 and 2, respectively. Statistical analysis revealed significant differences for CRF and IOPg between the study groups. The mean CRF and IOPg values of patients with SSc were higher when compared with normal controls. According to the results of our study, one can conclude that corneal biomechanical properties would be changed in patients with SSc and this can be determined by CRF.

  8. The effects of the modulus of the lens material on intraocular pressure measurement through soft contact lenses.

    Science.gov (United States)

    Boyraz, S; Güngör, I

    2013-09-01

    To investigate the effects of the modulus of the lens material on the intraocular pressure measurement using the Tono-Pen XL applanation tonometer through soft contact lenses. Thirty eyes of 15 patients with myopia were evaluated. Intraocular pressure (IOP) measurements were performed using Tono-Pen XL directly over cornea, and subsequently through three soft contact lenses made up of different lens materials. All were -3.00 diopter soft contact lenses: lotrafilcon A with a low water content (24%) and high modulus (1.4 MPa) (CL-I), balafilcon A with a moderate water content (36%) and moderate modulus (1.1 MPa) (CL-II), and vifilcon A with a moderate water content (55%) and low modulus (0.79 MPa) (CL-III). IOP measurements through contact lenses were compared with each other, and with direct corneal measurements. The mean age of the patients (11 males and 4 females) was 26.86±5.62 years. All measurements obtained through CLs were significantly higher than the direct corneal measurements. The measurements through CLs differed by 4.61±0.54 mmHg (P=0,001), 2.9±0.46 mmHg (P=0.001), and 1.94±0.51 mmHg (P=0,003) for CL-I, CL-II and CL-III, respectively. In the paired comparisons of measurements through CLs, all comparisons were significant except the comparison of measurements through CL-II and CL-III (P=0.128). IOP measurements through silicone-hydrogel contact lenses with a high modulus and low water content were higher compared to the other contact lenses. While measuring IOP through CLs, the clinicians should consider the effect of the lens material and the features of the device used.

  9. Influence of bushenhuoxue on primary visual cortex' BDNF damage in rat model of chronic elevated intraocular pressure

    Directory of Open Access Journals (Sweden)

    Xiang Li

    2013-04-01

    Full Text Available AIM: To observe the effect of traditional Chinese medicine(TCMof bushenhuoxue on primary visual cortex(PVCbrain-derived neurotrophic factor(BDNFin rat model of chronic elevated intraocular pressure(EIOP, and explore the mechanism of it initially. METHODS: The rat model of chronic EIOP was established by unilaterally cauterizing 3 episcleral veins, then 30 rats were divided into 3 groups randomly: control group, model group, and treatment group. After given drugs or normal saline for 8 weeks, the rats were put to death. The effect of intraocular pressure(IOP, expression of BDNF and ultrastructure of neuron cell in the PVC was observed. RESULTS: Unilaterally cauterizing episcleral veins increased IOP of the rat model obviously, there was significant difference compared with pre-operation(P<0.01. Semi-quantitative pathological analysis on PVC showed that BDNF of total area in the model group was(82438±2597.39S/μm2,mean optical density was(1155.9±123.14, integrated optical density was(12915±673.28, compared with the control group {total area was(132370±7588.47S/μm2, mean optical density was(5365±379.65, integrated optical density was(35102±2648.5}, there were statistical differences(all P<0.05,there was statistical difference in BDNF of total area between model group and treatment group{(108980±9126.77S/μm2, P<0.05}, significant difference in mean optical density between the model group and treatment group(3220.4±413.67, P<0.05, statistical difference in integrated optical density between the model group and treatment group(23821±3431.68, P<0.05. CONCLUSION: TCM of bushenhuoxue can repair the PVC damage in the rat model of chronic EIOP by enhancing expression of BDNF, improving ultrastructure of neuron cell.

  10. The effect of circadian blood pressure pattern on presence of fragmented QRS complexes in hypertensive subjects.

    Science.gov (United States)

    Eyuboglu, Mehmet; Karabag, Yavuz; Karakoyun, Suleyman; Akdeniz, Bahri

    2017-08-01

    The association of deteriorated circadian blood pressure (BP) variability with presence of fragmented QRS (fQRS) on electrocardiography (ECG) is not clear. The present study aims to evaluate the relationship of BP patterns with presence of fQRS on ECG. A total of 338 consecutive newly diagnosed and never treated hypertensive patients who are without left ventricular hypertrophy and underwent 24-hour ambulatory BP monitoring were enrolled. Patients were classified as dippers, nondippers, and reverse dippers according to ambulatory BP monitoring results. The groups were compared regarding frequency of fQRS on ECG. The frequency of fQRS was significantly higher in reverse dippers compared with dippers (37.7% vs. 20.6%, P = .013). In multivariate logistic regression analysis, nighttime systolic BP was found to be an independent predictor of fQRS on ECG (P reverse dipping BP pattern in hypertensive patients (P = .004, odds ratio: 2.416, 95% confidence interval = 1.327-4.396). In conclusion, as a marker of fibrosis and higher fibrotic burden within myocardium, fQRS may be useful to determine the high-risk hypertensive patients in the absence of left ventricular hypertrophy. Copyright © 2017 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

  11. Study on the pathogenesis of transient intraocular pressure after laser iridectomy with Krypton laser combined with Q-switched Nd:YAG laser

    Directory of Open Access Journals (Sweden)

    Zhi-Juan Pei

    2017-12-01

    Full Text Available AIM: To study the pathogenesis of transient intraocular pressure(IOPafter laser iridectomy with Krypton laser combined with Q-switched Nd:YAG laser. METHODS: Totally 42 healthy rabbits(84 eyesprovided by the Animal Experimental Center of our hospital were selected, including 18 female rabbits, 24 male rabbits, average weight 2.24±0.31kg, and they were randomly divided into 6 groups, 7 rats in each group(14 eyes. We observed the change of intraocular pressure after laser iridectomy surgery at 20min, 2, 6, 18, 24h and the nitric oxide(NO, malondialdehyde(MDA, superoxide dismutase(SOD, 6-keto-prostaglandin(6-keto-PGF1αand nitric oxide synthase(NOScontent in aqueous. RESULTS: There was no significant difference in intraocular pressure, NO, NOS, SOD, MAD and 6-keto- PGF1α before operation(P>0.05. The intraocular pressure increased after operation, and the difference was statistically significant(PP>0.05. The levels of NO, NOS and SOD in the aqueous humor of the two groups decreased 20min, 2 and 6h after the operation(PP>0.05. The levels of MDA and 6-keto-prostaglandin in the aqueous humor increased after the operation, and the difference was statistically significant at 20min, 2 and 6h after operation(PP>0.05.CONCLUSION: The increase of transient intraocular pressure after laser iridectomy may relate to the increase of malondialdehyde, 6-keto-prostaglandin content and the decrease of superoxide dismutase and nitric oxide in the aqueous humor after operation.

  12. Changes in blood pressure and sleep duration in patients with blue light-blocking/yellow-tinted intraocular lens (CHUKYO study).

    Science.gov (United States)

    Ichikawa, Kazuo

    2014-07-01

    Blood pressure and sleep duration may be influenced by retinal light exposure. Cataracts may exert such an influence by decreasing the transparency of the crystalline lens. A large-scale clinical study was conducted to examine changes in blood pressure and sleep duration after intraocular lens (IOL) implantation during cataract surgery and to investigate how different types of IOL influence the degree of these effects. Using a questionnaire, we collected information, including blood pressure measurement and sleep duration, from 1367 patients (1367 eyes) before IOL implantation, 1 week after IOL implantation and 1 month after IOL implantation. Systolic and diastolic blood pressures were significantly decreased in the total patient group after implantation. The decrease in systolic blood pressure 1 month after implantation was significantly more in patients who received a yellow-tinted IOL than it was in those who received an ultraviolet (UV) light-filtering IOL. The post-implantation sleep duration, including naps, became shorter in patients who had slept too much and became longer in those who had slept too little before IOL implantation. Our observations suggest that a yellow-tinted IOL is better for patients with high blood pressure than a UV light-filtering IOL. Furthermore, the yellow-tinted IOL is as good as the UV light-filtering IOL for improving sleep duration. A pale yellow-tinted IOL is likely to be superior to a moderate yellow-tinted IOL in terms of allowing patients to discriminate different colors. Thus, the pale yellow-tinted IOL appears to be better for patients than the UV light-filtering IOL and the moderate yellow-tinted IOL.

  13. Effect of elevated intraocular pressure on the thickness changes of cat laminar and prelaminar tissue using optical coherence tomography.

    Science.gov (United States)

    Zhao, Qiuyun; Qian, Xiuqing; Li, Lin; Sun, Weijian; Huang, Shan; Liu, Zhicheng

    2014-01-01

    The aim of this study was to examine shape the changes of the lamina cribrosa (LC) under different intraocular pressures (IOPs) with different periods. Images of the optic nerve head were obtained using enhanced depth imaging spectral domain optical coherence tomography (EDI SD-OCT). After an initial scan of the IOP at native pressure, subsequent scanning was taken when the IOP values reached 40, 60, 80 and 100 mm Hg. Then scans continued with the IOP maintained at 100 mm Hg for 1 hour, 2 hours, 3 hours and 4 hours. The thicknesses of the LC and prelaminar tissue were measured and the curvature of the LC was calculated. Our study found that as IOP increased, the thicknesses of both LC and prelaminar tissue decreased and the thickness variation of the LC correlated significantly with the increases of IOP when IOP was higher than 60 mm Hg. An exponential function was proposed to express the relationship between IOP and the thickness variations of LC and prelaminar tissue. Creep curves of the LC and prelaminar tissue was also obtained using the Prony model. In conclusion, both the thickness of the prelaminar tissue and LC thinned as the IOP elevated. The thickness of the LC also decreased after 4 hours of constant 100 mm Hg pressure.

  14. Development of a wireless intra-ocular pressure monitoring system for incorporation into a therapeutic glaucoma drainage implant

    Science.gov (United States)

    Kakaday, Tarun; Plunkett, Malcolm; McInnes, Steven; Li, Jim S. Jimmy; Voelcker, Nicolas H.; Craig, Jamie E.

    2008-12-01

    Glaucoma is a common cause of blindness. Wireless, continuous monitoring of intraocular pressure (IOP) is an important, unsolved goal in managing glaucoma. An IOP monitoring system incorporated into a glaucoma drainage implant (GDI) overcomes the design complexity associated with incorporating a similar system in a more confined space within the eye. The device consists of a micro-electro-mechanical systems (MEMS) based capacitive pressure sensor integrated with an inductor printed directly onto a polyimide printed circuit board (PCB). The device is designed to be incorporated onto the external plate of a therapeutic GDI. The resonance frequency changes as a function of IOP, and is tracked remotely using a spectrum analyzer. A theoretical model for the reader antenna was developed to enable maximal inductive coupling with the IOP sensor implant. Pressure chamber tests indicate that the sensor implant has adequate sensitivity in the IOP range with excellent reproducibility over time. Additionally, we show that sensor sensitivity does not change significantly after encapsulation with polydimethylsiloxane (PDMS) to protect the device from fluid environment. In vitro experiments showed that the signal measured wirelessly through sheep corneal and scleral tissue was adequate indicating potential for using the system in human subjects.

  15. The relationship between measurement method and corneal structure on apparent intraocular pressure in glaucoma and ocular hypertension.

    Science.gov (United States)

    Nessim, Maged; Mollan, Susan P; Wolffsohn, James S; Laiquzzaman, Mohammad; Sivakumar, Subramaniam; Hartley, Stephanie; Shah, Sunil

    2013-04-01

    To analyse the relationship between measured intraocular pressure (IOP) and central corneal thickness (CCT), corneal hysteresis (CH) and corneal resistance factor (CRF) in ocular hypertension (OHT), primary open-angle (POAG) and normal tension glaucoma (NTG) eyes using multiple tonometry devices. Right eyes of patients diagnosed with OHT (n=47), normal tension glaucoma (n=17) and POAG (n=50) were assessed. IOP was measured in random order with four devices: Goldmann applanation tonometry (GAT); Pascal dynamic contour tonometer (DCT); Reichert ocular response analyser (ORA); and Tono-Pen XL. CCT was then measured using a hand-held ultrasonic pachymeter. CH and CRF were derived from the air pressure to corneal reflectance relationship of the ORA data. Compared to the GAT, the Tonopen and ORA Goldmann equivalent (IOPg) and corneal compensated (IOPcc) measured higher IOP readings (F=19.351, pIOP and had the lowest variance. CCT was significantly different (F=8.305, pmeasures were not affected by CCT. The DCT was generally not affected by corneal biomechanical factors. This study suggests that as the true pressure of the eye cannot be determined non-invasively, measurements from any tonometer should be interpreted with care, particularly when alterations in the corneal tissue are suspected. Copyright © 2012 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  16. Homeostasis in Primates in the Hyperdynamic Environment. [circadian timekeeping and effects of lower body positive pressure on sleep

    Science.gov (United States)

    Fuller, C. A.

    1985-01-01

    The influence of chronic centrifugation upon the homestatic regulation of the circadian timekeeping system was examined. The interactions of body temperature regulation and the behavioral state of arousal were studied by evaluating the influence of cephalic fluid shifts induced by lower body positive air pressure (LBPP), upon these systems. The small diurnal squirrel monkey (Saimiri sciureus) was used as the non-human primate model. Results show that the circadian timekeeping system of these primates is functional in the hyperdynamic environment, however, some of its components appear to be regulated at different homeostatic levels. The LBPP resulted in an approximate 0.7 C decrease in DBT (p 0.01). However, although on video some animals appeared drowsy during LBPP, sleep recording revealed no significant changes in state of arousal. Thus, the physiological mechanisms underlying this lowering of body temperature can be independent of the arousal state.

  17. Comparison of brimonidine-timolol and dorzolamide-timolol in the management of intraocular pressure increase after phacoemulsification

    Directory of Open Access Journals (Sweden)

    Adem Turk

    2015-10-01

    Full Text Available AIM: To compare the effectiveness of brimonidine/timolol fixed combination (BTFC and dorzolamide/timolol fixed combination (DTFC in the management of short-term intraocular pressure (IOP increase after phacoemulsification surgery.METHODS: Eighty eyes of 80 patients undergoing phacoemulsification and intraocular lens (IOL implantation were randomly assigned into three groups. Group 1 consisted of 28 eyes and represented the control group. Group 2 consisted of 25 eyes undergoing phacoemulsification surgery and BTFC was instilled at the end of surgery. Group 3 consisted of 27 eyes undergoing phacoemulsification surgery and DTFC was instilled at the end of surgery. IOP was measured preoperatively and 6, 24h and 1wk postoperatively.RESULTS: There was no statistically significant difference in preoperative baseline IOP among the three groups (P=0.84. However, IOP was significantly lower in groups 2 and 3 compared to the control group (P<0.05 for all comparisons at all postoperative visits. There was no significant difference between groups 2 and 3 at any visit. Eight eyes (28.6% in the control group, two (8% in Group 2 and one (3.7% in Group 3 had IOP >25 mm Hg at 6h after surgery (P=0.008. However, IOP decreased and was >25 mm Hg in only one eye in each group at 24h after surgery.CONCLUSION: BTFC and DTFC have similar effects in reducing increases in IOP after phacoemulsification surgery and can both be recommended for preventing IOP spikes after such surgery.

  18. Relación entre amplitud del pulso ocular y presión intraocular:: efectividad del tratamiento hipotensor Association of ocular pulse amplitude and intraocular pressure and effectiveness of the hypotensive treatment

    Directory of Open Access Journals (Sweden)

    Itahimy Ambrós Gómez

    2010-06-01

    Full Text Available OBJETIVOS: Determinar la asociación entre la amplitud del pulso ocular y la tensión ocular en los pacientes con glaucoma primario de ángulo abierto según grupos de tratamiento. Evaluar la amplitud del pulso ocular como medio para medir la efectividad de la terapia antihipertensiva ocular. Definir correlación entre espesor corneal central/tensión ocular y entre espesor corneal/amplitud del pulso usando el tonómetro de contorno dinámico. MÉTODOS: Se estudiaron 90 pacientes mayores de 15 años con diagnóstico reciente de glaucoma primario de ángulo abierto que aún no habían recibido tratamiento alguno; con ellos se conformaron tres grupos de estudio de forma aleatoria y según el medicamento indicado: Grupo l: Timolol 0,5 %, Grupo II: Travoprost (Travatán 0,2 % y Grupo III: Dorzolamida (Trusopt 2 %. A estos pacientes se les tomó la medida del espesor corneal central por paquimetría previa al tratamiento, a la semana, al mes y a los 3 meses en el servicio de glaucoma del Hospital "Ramón Pando Ferrer" (diciembre-2006 a mayo-2007. Se midieron además las variables presión intraocular y amplitud del pulso ocular. RESULTADOS: Se encontró menor amplitud del pulso a medida que disminuía la presión intraocular, existió mayor descenso de la presión y de la amplitud del pulso en el grupo tratado con Travoprost, hubo para este grupo de tratamiento una mejor correlación entre ambas variables. No se encontró correlación entre el espesor corneal central y presión intraocular, ni entre espesor corneal y amplitud del pulso. CONCLUSIONES: Monitorear la presión y la amplitud del pulso puede ser eficaz para conocer el efecto de la terapéutica hipotensora ocular.OBJECTIVES: To determine the association of the ocular pulse amplitude and the ocular pressure in patients with primary open angle glaucoma by groups under treatment; to evaluate the ocular pulse amplitude as a means to assess the effectiveness of anti-hypertensive ocular therapy

  19. Relation between abnormalities in circadian blood pressure rhythm and target organ damage in normotensives.

    Science.gov (United States)

    Soylu, Ahmet; Yazici, Mehmet; Duzenli, Mehmet Akif; Tokac, Mehmet; Ozdemir, Kurtuluş; Gok, Hasan

    2009-05-01

    To determine the individual effect of abnormalities in blood pressure (BP) circadian rhythm (non-dipping status (NDS), increased morning BP (MBP) or increased MBP surge (MBPS)) on target organ damage (TOD) and which of these is more closely related to TOD in normotensives. The 24-h ambulatory BP monitoring (ABPM) and echocardiography were performed and urinary albumin excretion (UAE) was measured in 47 dipper (28 women, mean age 45.8 +/- 9.3) and 32 non-dipper (25 women, mean age 49.1 +/- 8.3 years) normotensive subjects. The left ventricular mass index (LVMI) was higher in non-dipper group (103.8 +/- 24.1 vs 91.6 +/- 23.5 g/m2, P=0.03). UAE in non-dipper group was higher, but the difference between the two was not statistically significant (18.9 [10.3, 28.9] vs 14.1 [7.5, 23.8], P=0.11). In multivariate analysis, both LVMI and UAE were affected by NDS and MBP independent of other confounding variables (for LVMI; Coefficient =0.27, P=0.01 and Coefficient =0.37, P=0.001, respectively, and for UAE; Coefficient =0.27, P=0.02 and Coefficient =0.28, P=0.01, respectively). It may be postulated that increased night and MBP are the factors that cause TOD, and it seems reasonable to attempt to restore normal diurnal rhythm of the BP even in normotensive subjects.

  20. Effect of ophthalmic administration of S-596 (Arotinolol) on intraocular pressure and haemodynamics in health volunteers: comparison with timolol.

    Science.gov (United States)

    Nakashima, M; Uematsu, T; Takiguchi, Y; Hashimoto, H; Watanabe, I; Morioka, S; Hibino, T

    1985-01-01

    The effects on intraocular pressure (IOP) and haemodynamics of two beta-blockers, arotinolol and timolol, administered topically to the eye, were studied in 6 healthy volunteers in a cross-over trial. 0.5% timolol or 0.5% arotinolol ophthalmic solutions drop was instilled in both eyes of the volunteers at an interval of 48 hours. Timolol lowered IOP by about 31.9% 1 hour after administration and the effect continued until 3 h, whilst arotinolol lowered it significantly 2 h after instillation and the same maximum effect as that of timolol was obtained after 3 h. Arotinolol was detected in blood in all subject and timolol in blood in one subject, although it was found in all subjects in urine. Both drugs lowered heart rate at rest and attenuated the increase in the double product (products of blood pressure and heart rate) at exercise. The effect of timolol on the double products was larger. Thus, arotinolol and timolol decreased IOP to similar extent, although the maximal effect of arotinolol was delayed. Arotinolol as well as timolol affected haemodynamics through absorption into circulation, but the former had less effect on haemodynamics during exercise.

  1. Influence of Large Intraocular Pressure Reduction on Peripapillary OCT Vessel Density in Ocular Hypertensive and Glaucoma Eyes.

    Science.gov (United States)

    Holló, Gábor

    2017-01-01

    Optical coherence tomography (OCT) angiography is a new noninvasive method to measure peripapillary microcirculation in various retinal layers, separately. In this case series, we investigate whether large medical intraocular pressure (IOP) reduction (>50% of the untreated baseline value) to IOP≤18 mm Hg influences peripapillary angioflow density (PAFD, percentage of the analyzed retinal area) in the retinal nerve fiber layer in high pressure (IOP≥35 mm Hg) ocular hypertensive and glaucoma eyes. The AngioVue OCT (software version 2015.100.0.33) was used for PAFD measurements in 6 eyes of 4 consecutive newly detected young patients (age: 32 to 45 y; 2 ocular hypertensive and 4 pigment dispersion/glaucoma eyes). PAFD was measured on high quality images (signal strength index >50) at untreated baseline and 2 to 4 weeks later when the IOP was medically reduced. The PAFD measurements were immediately followed by IOP measurements. Untreated and under treatment IOP ranged between 35 and 42 mm Hg, and 12 and 18 mm Hg, respectively (IOP decrease >50% in all cases). Peripapillary PAFD increased in all cases, in 5 cases the increase was greater than the baseline value plus 2 test-retest variability determined earlier by us on glaucoma eyes. The results suggest that large medical IOP reduction may result in clinically significant increase of peripapillary capillary perfusion in the retinal nerve fiber layer in young individuals with high untreated IOP. To evaluate the clinical usefulness of OCT angiography in the management of glaucoma detailed prospective clinical studies are necessary.

  2. Effects of simulated microgravity on circadian rhythm of caudal arterial pressure and heart rate in rats and their underlying mechanism

    Directory of Open Access Journals (Sweden)

    Li CHEN

    2016-04-01

    Full Text Available Objective  To explore the effects of simulated microgravity on the circadian rhythm of rats' caudal arterial pressure and heart rate, and their underlying mechanism. Methods  Eighteen male SD rats (aged 8 weeks were randomly assigned to control (CON and tail suspension (SUS group (9 each. Rats with tail suspension for 28 days were adopted as the animal model to simulate microgravity. Caudal arterial pressure and heart rate of rats were measured every 3 hours. The circadian difference of abdominal aorta contraction was measured by aortic ring test. Western blotting was performed to determine and compare the protein expression level of clock genes such as Per2 (Period2, Bmal1 (Aryl hydrocarbon receptor nuclear translocatorlike and dbp (D element binding protein in suprachiasmatic nucleus (SCN and abdominal aorta of rats in CON and SUS group at different time points. Results  Compared with CON group, the caudal arterial pressure, both systolic and diastolic pressure, decreased significantly and the diurnal variability disappeared, meanwhile the heart rate increased obviously and also the diurnal variability disappeared in rats of SUS group. Compared with CON group, the contraction reactivity of abdominal aorta decreased with disappearence of the diurnal variability, and also the clock genes expression in SCN and abdominal aorta showed no diurnal variability in rats of SUS group. Conclusion  Simulated microgravity may lead to circadian rhythm disorders in rats' cardiovascular system, which may be associated with the changes of the clock genes expression. DOI: 10.11855/j.issn.0577-7402.2016.04.06

  3. Influence of head flexion on intraocular pressure, cardiovascular, and respiratory responses in patients undergoing cataract surgery after endotracheal intubation

    Directory of Open Access Journals (Sweden)

    MR Safavi

    2007-11-01

    Full Text Available Background: In cataract surgery, the periorbital area is prepared anddraped after induction of general anesthesia and endotracheal intubation (ETI.For this purpose, the patient’s head and neck is usually flexed 30 to 45degrees. Neck flexion causes displacement of the endotracheal tube tip towardthe carina. Stimulation of the tracheal mucosa may cause bucking, increasedintraocular pressure (IOP, laryngospasm and/or bronchospasm, during lightanesthesia. Laryngeal constriction and all components of the tracheal responsemay affect end-tidal carbon dioxide pressure (PETCO2 and peripheral arterialhemoglobin oxygen saturation (SpaO2. Thus, in the current study, weinvestigated the influence of head and neck flexion on heart rate (HR, systolicand diastolic blood pressure (SAP and DAP, SpaO2, PETCO2, and IOP in patientsundergoing cataract surgery with endotracheal intubation during generalanesthesia.Patients and Methods: The present prospective study comprised patientsaged from 40 to 80 year with 106 American Society of Anesthesia (ASA physicalstatus I and II. Anesthesia was induced with thiopental sodium, lidocaine andfentanyl. Atracurium 0.5 mg/kg was administered to facilitate trachealintubation. HR, SAP, DAP, SpaO2, PETCO2, and IOP were measured at 1, 2, and 5minutes after head flexion.Results: Mean SAP, DAP, IOP, and HR was increased after ETI and headflexion compared with baseline values. PETCO2 and SpaO2 were decreased after ETIand at 1, 2 minutes after head flexion compared with baseline values.Conclusion: In patients undergoing cataract surgery during generalanesthesia, endotracheal tube movement caused changes in head and neck positionresulting in significant effects on heart rate, systolic and diastolic bloodpressures, laryngeal reflexes, SpaO2, PETCO2, and intraocular pressure.

  4. Effects of systemic administration of 0.5% tropicamide on intraocular pressure, pupillary diameter, blood pressure, and heart rate in normal cats.

    Science.gov (United States)

    Schmidt, Kristiane S; Hacker, Dennis V; Kass, Philip H; Barkhoodarian, Alex L

    2006-01-01

    The objective of the study was to determine the effects of systemic 0.5% tropicamide on intraocular pressure (IOP), pupillary diameter (PD), blood pressure, and heart rate (HR) in normal felines with normotensive eyes. Intraocular pressure, PD, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and HR were measured in 18 clinically healthy cats. Each of the previously mentioned parameters was measured every 30 min during the trial period. At T(60), each cat was treated with one to two drops of 0.5% tropicamide ophthalmic solution placed on the dorsal aspect of the tongue. Changes in SBP, DBP, MBP, and HR were evaluated using one-way repeated measures analysis of variance, with time as the repeated factor. IOP and PD were evaluated using two-way repeated measures analysis of variance, with time and side (OD vs. OS) as the repeated factors. P values less than or equal to 0.05 were considered statistically significant. After lingual tropicamide administration, the mean PD at T(60) was 3.53 mm OD and 3.53 mm OS. The mean PD at T(90) was 6.36 mm OD and 6.31 mm OS. The mean PD at T(120) was 8.25 mm OD and 8.19 mm OS. This change in PD from T(60), T(90), and T(120) was statistically significant, demonstrating a linear increase in PD over time after tropicamide application on the tongue (Ptropicamide application on the tongue (P=0.034). There was no statistically significant difference in IOP when comparing the right eye to the left eye (P=0.28). There were no statistically significant differences in SBP, DBP, MBP, and HR values over time for the duration of the study. We conclude that although lingual application of tropicamide appears to result in systemic absorption, causing significant pupillary dilation and elevations in IOP, systemic effects on SBP, DBP, MBP, and HR were not observed.

  5. Bimatoprost ophthalmic solution 0.03% lowered intraocular pressure of normal-tension glaucoma with minimal adverse events

    Directory of Open Access Journals (Sweden)

    Tsumura T

    2012-09-01

    Full Text Available Toyoaki Tsumura,1 Keiji Yoshikawa,2 Hirotaka Suzumura,3 Tairo Kimura,4 Satoshi Sasaki,5 Itaru Kimura,6 Ryuji Takeda71Department of Ophthalmology, Fussa Hospital, Fussa, Tokyo, Japan; 2Yoshikawa Eye Clinic, Machida, Tokyo, Japan; 3Department of Ophthalmology, Nakano General Hospital, Nakano, Tokyo, Japan; 4Ueno Eye Clinic, Ueno, Tokyo, Japan; 5Sasaki Eye Clinic, Ueno, Tokyo, Japan; 6Department of Ophthalmology, Juntendo University Urayasu Hospital, Urayasu, Chiba, Japan; 7Department of Biological Chemistry, Faculty of Agriculture, Kinki University, Nara, Nara, JapanPurpose: The aim of this study was to evaluate the efficacy and safety of bimatoprost ophthalmic solution 0.03% (bimatoprost in Japanese normal-tension glaucoma (NTG patients with an intraocular pressure (IOP of 18 mmHg or less.Methods: Bimatoprost was instilled into the unilateral conjunctival sac of Japanese NTG patients with a baseline IOP of 18 mmHg or less. The time courses of IOP, conjunctival hyperemia, superficial punctate keratitis, and adverse events were examined at 2, 4, 8, and 12 weeks post bimatoprost instillation.Results: Thirty-two of the 38 enrolled NTG patients (mean age, 64.1 ± 12.6 years; 19 males and 19 females completed the study, with six patients unable to complete the study (two patients discontinued because of side effects and four patients withdrew. The levels of IOP in the treated eyes were significantly reduced (P < 0.0001 from the baseline IOP levels. No significant change in IOP was observed in the fellow eyes. There were significant increases in conjunctival hyperemia. No significant superficial punctate keratitis scores were noted between the baseline and each point examined. Eyelash disorder, eyelid pigmentation, and deepening of the upper eyelid sulcus were observed in 28, six, and three eyes, respectively.Conclusion: Bimatoprost effectively lowered the IOP. It was well tolerated in Japanese NTG patients, with few patients having to discontinue

  6. Comparison of different intraocular pressure measurement techniques in normal eyes, post surface and post lamellar refractive surgery

    Directory of Open Access Journals (Sweden)

    Shousha SM

    2013-01-01

    Full Text Available Shireen MA Shousha, Mahmoud AH Abo Steit, Mohamed HM Hosny, Wael A Ewais, Ahmad MM ShalabyDepartment of Ophthalmology, Faculty of Medicine, Cairo University, Cairo, EgyptBackground: The purpose of this study was to determine the accuracy of intraocular pressure (IOP measurement after laser in situ keratomileusis (LASIK or epithelial laser in situ keratomileusis (Epi-LASIK using Goldmann applanation tonometry, air puff tonometry, ocular response analyzer corneal compensated IOP (ORA IOPcc and Pentacam corrected IOP.Methods: A prospective comparative clinical study was conducted between February and September 2011 on 30 eyes divided into four groups, i.e. 20 corneas of 10 patients before LASIK (group A, 20 corneas of the same patients 2 months postoperatively (group B, 10 corneas of five patients before Epi-LASIK (group C, and 10 corneas of the same patients 2 months postoperatively (group D. Patient age ranged from 20 to 50 years. IOP was measured using Goldmann applanation and air puff tonometry, ORA corneal compensation, and Pentacam correction (which also measured central corneal thickness.Results: Significant positive linear correlations were found between IOP values measured by Goldmann applanation tonometry and other techniques, and with preoperative pachymetry in group A. The correlation between preoperative Pentacam-corrected and preoperative ORA corneal-compensated IOP was strongest for Goldmann applanation tonometry (r = 0.97 and r = 0.858 respectively, P < 0.001. Compared with preoperative values, postoperative IOP measured by the four methods were significantly lower. The difference was statistically significant when IOP was measured using Goldmann applanation and air puff tonometry compared with the ORA and Pentacam methods (P < 0.001 for LASIK patients and P = 0.017 for Epi-LASIK patients. Nonsignificant correlations were found between the degree of lowering of postoperative IOP and postoperative pachymetry in groups B and D

  7. A Randomized Trial of a Schlemm's Canal Microstent with Phacoemulsification for Reducing Intraocular Pressure in Open-Angle Glaucoma.

    Science.gov (United States)

    Pfeiffer, Norbert; Garcia-Feijoo, Julian; Martinez-de-la-Casa, Jose M; Larrosa, Jose M; Fea, Antonio; Lemij, Hans; Gandolfi, Stefano; Schwenn, Oliver; Lorenz, Katrin; Samuelson, Thomas W

    2015-07-01

    To assess the safety and effectiveness of the Hydrus Microstent (Ivantis, Inc, Irvine, CA) with concurrent cataract surgery (CS) for reducing intraocular pressure (IOP) in open-angle glaucoma (OAG). Prospective, multicenter, randomized, single-masked, controlled clinical trial. One hundred eyes from 100 patients 21 to 80 years of age with OAG and cataract with IOP of 24 mmHg or less with 4 or fewer hypotensive medications and a washed-out diurnal IOP (DIOP) of 21 to 36 mmHg. On the day of surgery, patients were randomized 1:1 to undergo CS with the microstent or CS alone. Postoperative follow-up was at 1 day, 1 week, and 1, 3, 6, 12, 18, and 24 months. Washout of hypotensive medications was repeated at 12 and 24 months. Response to treatment was defined as a 20% or more decrease in washed out DIOP at 12 and 24 months of follow-up compared with baseline. Mean DIOP at 12 and 24 months, the proportion of subjects requiring medications at follow-up, and the mean number of medications were analyzed. Safety measures included change in visual acuity, slit-lamp observations, and adverse events. The proportion of patients with a 20% reduction in washed out DIOP was significantly higher in the Hydrus plus CS group at 24 months compared with the CS group (80% vs. 46%; P = 0.0008). Washed out mean DIOP in the Hydrus plus CS group was significantly lower at 24 months compared with the CS group (16.9±3.3 mmHg vs. 19.2±4.7 mmHg; P = 0.0093), and the proportion of patients using no hypotensive medications was significantly higher at 24 months in the Hydrus plus CS group (73% vs. 38%; P = 0.0008). There were no differences in follow-up visual acuity between groups. The only notable device-related adverse event was focal peripheral anterior synechiae (1-2 mm in length). Otherwise, adverse event frequency was similar in the 2 groups. Intraocular pressure was clinically and statistically significantly lower at 2 years in the Hydrus plus CS group compared with the CS alone group

  8. Pattern of intraocular pressure reduction following laser trabeculoplasty in open-angle glaucoma patients: comparison between selective and nonselective treatment

    Directory of Open Access Journals (Sweden)

    Almeida Jr ED

    2011-07-01

    Full Text Available Eglailson Dantas Almeida Júnior1, Luciano Moreira Pinto1,2, Rodrigo Antonio Brant Fernandes1,2, Tiago Santos Prata1,31Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil; 2Cerpo Oftalmologia, São Paulo, Brazil; 3Hospital Medicina dos Olhos, São Paulo, BrazilObjective: To compare the pattern of intraocular pressure (IOP reduction following selective laser trabeculoplasty (SLT versus argon laser trabeculoplasty (ALT in open-angle glaucoma (OAG patients, and to investigate the ability of initial IOP reduction to predict mid-term success.Methods: A prospective, nonrandomized, interventional case series was carried out. Consecutive uncontrolled OAG glaucoma patients underwent SLT or ALT; the same preoperative medical regimen was maintained during follow-up. Data collected included age, type of OAG, pre- and postoperative IOP, number of glaucoma medications, and surgical complications. Post-treatment assessments were scheduled at day 1 and 7 and months 1, 3, and 6.Results: A total of 45 patients (45 eyes were enrolled [SLT group (n = 25; ALT group (n = 20]. Groups were similar for age, baseline IOP, and number of glaucoma medications (P ≥ 0.12. We found no significant differences in mean IOP reduction between SLT (5.1 ± 2.5 mmHg; 26.6% and ALT (4.4 ± 2.8 mmHg; 22.8% groups at month 6 (P = 0.38. Success rates (IOP ≤ 16 mmHg and IOP reduction ≥25% at last follow-up visit were similar for SLT (72% and ALT (65% groups (P = 0.36. Comparing the pattern of IOP reduction (% of IOP reduction at each visit between groups, we found a greater effect following SLT compared with ALT at day 7 (23.7% ± 13.7% vs 8.1% ± 9.5%; P < 0.001. No significant differences were observed at other time points (P ≥ 0.32. Additionally, the percentage of IOP reduction at day 7 and at month 6 were significantly correlated in the SLT group (R2 = 0.36; P < 0.01, but not in the ALT group (P = 0.89. Early postoperative success predicted late

  9. Relationship between raised intraocular pressure and ischemia-modified albumin in serum and humor aqueous: a pilot study in rabbits.

    Science.gov (United States)

    Taskiran Comez, Arzu; Cakir, Dilek Ulker; Tutunculer, Funda Kirtay; Gencer, Baran; Tufan, Hasan Ali

    2014-01-01

    We evaluated the relationship between increased intraocular pressure (IOP), ischemia-modified albumin levels in serum (IMA-s) and in humor aqueous (IMA-HA) in rabbits. Twenty-five albino New Zealand rabbits weighing between 2.0 and 2.8 kg were used in this pilot study. With permission from Canakkale Onsekiz Mart University Animal Ethics Committee, the IOP of both eyes of each rabbit were recorded with a Tonopen (Tono-Pen XL, Reichart Inc., Depew, NY, USA) after the application of topical proparacaine 0.5% HCl anesthesia. Blood (4 mL) was collected from the marginal ear vein and an intracameral injection of 2.3 mg/mL sodium hyaluronate and subconjunctival dexamethasone was given in the right eye. Anterior chamber aqueous fluid was obtained using a limbal approach with a 27 gauge needle from both eyes. The left eyes were used as controls. IOP was measured on the 1(st), 3(rd) and 10(th) day after the initial injection, with Tonopen, IMA-s levels and IMA-HA examined simultaneously. Before the injections, IOP was 11.4±3.0 mm Hg in the right eye and 11.3±3.1 mm Hg in the left eye (P>0.05). There was a statistically significant difference between IMA-s levels before the IOP increase (IMA-s0) and IMA-s levels on the 1(st) and 3(rd) days after the increase in IOP (P=0.012 and P=0.01, respectively). No difference was observed between IMA-s0 and serum IMA levels on the 10(th) day (IMA-s10) after IOP increase (P=0.989). IMA-HA in the right eye in the first day after the injection was positively correlated with IOP (r=0.748; P=0.02). No other correlation is found between any other parameter with IMA-HA levels at any test time. A statistically significant positive correlation was observed between IMA-s values and IOP on the 1(st) and 3(rd) days (r=0.398, P=0.04 and r=0.382, P=0.04, respectively). There was no correlation between IMA-s levels and increased IOP on the 10(th) day after IOP increase (r=0.026, P=0.902). IMA may be an important indicator of acute damage caused by

  10. Effect of hemodialysis on visual acuity, intraocular pressure, and macular thickness in patients with chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Chelala E

    2015-01-01

    Full Text Available Elias Chelala,1,2,* Ali Dirani,1,2,* Ali Fadlallah,1,2 Elise Slim,1,2 Youssef Abdelmassih,1,2 Henry Fakhoury,3 Patrick Baz,1,2 Riad Bejjani1,2 1Faculty of Medicine, Saint-Joseph University, 2Hôtel-Dieu de France Hospital, Saint-Joseph University, 3Eye and Ear Hospital, Beirut, Lebanon *These two authors contributed equally to this work Background: The aim of this study was to evaluate the effects of hemodialysis (HD on visual acuity, intraocular pressure (IOP, and central foveal thickness (CFT in patients with chronic kidney disease.Materials and methods: Forty-nine eyes from 49 chronic kidney-disease patients were analyzed. Causes of chronic kidney disease included diabetes mellitus (n=9 patients, hypertensive nephrosclerosis (n=15 patients, and other causes (n=25 patients. All patients underwent HD in the Dialysis Unit of Hôtel-Dieu de France Hospital. Best-corrected visual acuity, CFT, and IOP were evaluated before and after HD. CFT was measured with spectral domain optical coherence tomography, and IOP was measured with Goldmann applanation tonometry.Results: Neither decimal best-corrected visual acuity (pre-HD 0.71±0.32, post-HD 0.72±0.31; P=0.877 nor CFT (pre-HD 251.39±39.29, post-HD 253.09±39.26; P=0.272 significantly changed after HD. However, mean IOP significantly decreased from 13.99±2.48 before HD to 12.65±2.41 mmHg after HD (P=0.001. IOP change was significantly correlated with serum albumin levels (P=0.008 and weight changes (P=0.047.Conclusion: HD can affect various ocular parameters. This is particularly true of IOP, which decreases significantly following HD. Keywords: chronic kidney disease, hemodialysis, visual acuity, central macular thickness, intraocular pressure

  11. O2 uptake and blood pressure regulation at the onset of exercise: interaction of circadian rhythm and priming exercise.

    Science.gov (United States)

    Faisal, Azmy; Beavers, Keith R; Hughson, Richard L

    2010-12-01

    Circadian rhythm has an influence on several physiological functions that contribute to athletic performance. We tested the hypothesis that circadian rhythm would affect blood pressure (BP) responses but not O(2) uptake (Vo(2)) kinetics during the transitions to moderate and heavy cycling exercises. Nine male athletes (peak Vo(2): 60.5 ± 3.2 ml·kg(-1)·min(-1)) performed multiple rides of two different cycling protocols involving sequences of 6-min bouts at moderate or heavy intensities interspersed by a 20-W baseline in the morning (7 AM) and evening (5 PM). Breath-by-breath Vo(2) and beat-by-beat BP estimated by finger cuff plethysmography were measured simultaneously throughout the protocols. Circadian rhythm did not affect Vo(2) onset kinetics determined from the phase II time constant (τ(2)) during either moderate or heavy exercise bouts with no prior priming exercise (τ(2) moderate exercise: morning 22.5 ± 4.6 s vs. evening 22.2 ± 4.6 s and τ(2) heavy exercise: morning 26.0 ± 2.7 s vs. evening 26.2 ± 2.6 s, P > 0.05). Priming exercise induced the same robust acceleration in Vo(2) kinetics during subsequent moderate and heavy exercise in the morning and evening. A novel finding was an overshoot in BP (estimated from finger cuff plethysmography) in the first minutes of each moderate and heavy exercise bout. After the initial overshoot, BP declined in association with increased skin blood flow between the third and sixth minute of the exercise bout. Priming exercise showed a greater effect in modulating the BP responses in the evening. These findings suggest that circadian rhythm interacts with priming exercise to lower BP during exercise after an initial overshoot with a greater influence in the evening associated with increased skin blood flow.

  12. Comparison of intraocular pressure, blood pressure, ocular perfusion pressure and blood flow fluctuations during dorzolamide versus timolol add-on therapy in prostaglandin analogue treated glaucoma subjects.

    Science.gov (United States)

    Januleviciene, Ingrida; Siaudvytyte, Lina; Diliene, Vaida; Barsauskaite, Ruta; Paulaviciute-Baikstiene, Daiva; Siesky, Brent; Harris, Alon

    2012-03-21

    To compare the effects of dorzolamide and timolol add-on therapy in open-angle glaucoma (OAG) patients previously treated with prostaglandin analogue (Pg), by evaluating fluctuations in the intraocular (IOP), blood (BP), ocular perfusion pressures (OPP) and retrobulbar blood flow (RBF) parameters. 35 OAG patients (35 eyes), 31 women (88.6%) age 63.3 (8.9) years were evaluated in a 3 month randomized, cross-over, single-masked study. During the experiments BP, heart rate, IOP and OPP were assessed 4 times per day (8-12-16-20 h). RBF was measured twice per day (8-20 h) using Color Doppler imaging in the ophthalmic (OA), central retinal (CRA), nasal (nSPCA) and temporal (tSPCA) posterior ciliary arteries. In each vessel, peak systolic velocity (PSV) and end-diastolic velocity (EDV) were assessed and vascular resistance (RI) calculated. Both add-on therapies lowered IOP in a statistically significant manner from 15.7 ± 2.4 mmHg at latanoprost baseline to 14.9 ± 2.2 mmHg using dorzolamide (p add-on therapy showed smaller IOP (2.0 ± 1.4), SPP (13.3 ± 7.9), systolic BP (13.5 ± 8.7) and diastolic BP (8.4 ± 5.4) fluctuations as compared to both latanoprost baseline or timolol add-on therapies. Higher difference between morning and evening BP was correlated to decreased evening CRA EDV in the timolol group (c = -0.41; p = 0.01). With increased MAP in the morning or evening hours, we found increased evening OA RI in timolol add-on group (c = 0.400, p = 0.02; c = 0.513, p = 0.002 accordingly). Higher MAP fluctuations were related to impaired RBF parameters during evening hours-decreased CRA EDV (c = -0.408; p = 0.01), increased CRA RI (c = 0.576; p add-on group. OPP fluctuations correlated with increased nSPCA RI (c = 0.453; p = 0.006) in the timolol group. OPP fluctuations were not related to IOP fluctuations in both add-on therapies (p add-on therapies lowered IOP in a statistically significant fashion dorzolamide add-on therapy showed lower fluctuations in IOP, SPP

  13. To evaluate the effects of dexmedetomidine on intraocular pressure and haemodynamic changes in response to laryngoscopy and tracheal intubation

    Directory of Open Access Journals (Sweden)

    Tanuja

    2014-01-01

    Full Text Available Background: The most important prerequisites for neurosurgeries are brain relaxation, need of stable haemodynamics with less fluctuation in intracranial pressure and speedy recovery from anaesthesia. Endotracheal intubation is the major stressful stimuli that can elicit a marked pressor response. Various drugs have been used to attenuate these reflexes. Dexmedetomidine, a highly selective alpha 2-adrenoceptor agonist, have neuroprotective, cardioprotective, and sedative effects so it is potentially useful during neuroanaesthesia. This is a prospective randomised control trial carried out to see whether administration of Dexmedetomidine prior to intubation can attenuate the various haemodynamic responses, intraocular pressure (IOP and the requirement of induction dose of propofol in control and study group. Materials and Methods: Fifty patients (ASA grade 1, 2 scheduled for intracranial tumour surgeries were divided into two groups (25 each. Group D received Dexmedetomidine 0.8 μg/kg i.v. over 10 mins and group C received 20 ml saline. Anaesthesia induced with Propofol, dose adjusted using bispectral index monitor. The groups were compared with IOP, Heart rate (HR, Mean arterial pressure (MAP, and dose of Propofol required for induction. Results : Groups were well matched for their demographic data and pre-operative. IOP in both the eyes decreases significantly after premedication and remained below baseline even after 10 th min of intubation in group D while in Group C; it increased significantly after intubation and remained above baseline. The difference between groups was also statistically significant. HR and MAP decreased significantly in patients of group D compared to group C (P < 0.05. Patients were more haemodynamicaly stable at all time points after premedication in group D (P < 0.05. Propofol requirements for induction was lesser in group D (P < 0.05. Bradycardia and hypotension incidences were higher in group D. Conclusion

  14. Exercise training prevents increased intraocular pressure and sympathetic vascular modulation in an experimental model of metabolic syndrome

    Directory of Open Access Journals (Sweden)

    E.F.S. Castro

    2015-04-01

    Full Text Available The present study aimed to study the effects of exercise training (ET performed by rats on a 10-week high-fructose diet on metabolic, hemodynamic, and autonomic changes, as well as intraocular pressure (IOP. Male Wistar rats receiving fructose overload in drinking water (100 g/L were concomitantly trained on a treadmill for 10 weeks (FT group or kept sedentary (F group, and a control group (C was kept in normal laboratory conditions. The metabolic evaluation comprised the Lee index, glycemia, and insulin tolerance test (KITT. Arterial pressure (AP was measured directly, and systolic AP variability was performed to determine peripheral autonomic modulation. ET attenuated impaired metabolic parameters, AP, IOP, and ocular perfusion pressure (OPP induced by fructose overload (FT vs F. The increase in peripheral sympathetic modulation in F rats, demonstrated by systolic AP variance and low frequency (LF band (F: 37±2, 6.6±0.3 vs C: 26±3, 3.6±0.5 mmHg2, was prevented by ET (FT: 29±3, 3.4±0.7 mmHg2. Positive correlations were found between the LF band and right IOP (r=0.57, P=0.01 and left IOP (r=0.64, P=0.003. Negative correlations were noted between KITT values and right IOP (r=-0.55, P=0.01 and left IOP (r=-0.62, P=0.005. ET in rats effectively prevented metabolic abnormalities and AP and IOP increases promoted by a high-fructose diet. In addition, ocular benefits triggered by exercise training were associated with peripheral autonomic improvement.

  15. The Effect of Oral Clonidine Pretreatment on Intraocular Pressure and Hemodynamic Stability After Succinylcholine Injection and Intubation in Cataract Surgery

    Directory of Open Access Journals (Sweden)

    M. Nikooseresht

    2007-08-01

    Full Text Available Background:Providing better surgical conditions with meticulous control of Intraocular Pressure (IOP is one of the most important factors that affect the success rate in ophthalmic surgery. Clonidine is a selective central α2 agonist with analgesic, antianxiety and sedative effects which makes it a good choice in premedication recently. In this study, we compared the effects of oral clonidine with oral diazepam as premedicants on IOP and hemodynamic stability after injection of succinylcholine and intubation in cataract surgery. Methods: 109 patients with physical status 1-2 were randomly assigned in 2 groups. The C Group (54 cases was treated with oral clonidine (3 mic/kg and the D group (55 cases was treated with oral diazepam (0.15 mg/kg, 2 hours before induction of anesthesia. Induction of general anesthesia in all patients was performed with sodium thiopental (5mg/kg, fontanel (2mic/kg & succinylcholine (1.5mg/kg. Heart rate and mean arterial blood pressure were measured before and immediately after induction and 5 & 10 minutes after intravenous injection of succinylcholine. Measurements of IOP were performed before and 5 and10 minutes after injection of succinylcholine. Results: IOPs’ were always lower in C group as compared with D group but the IOP difference between groups was only significant at 5 minutes after succinylcholine injection. Mean arterial blood pressure and pulse rate were lower in C group compared with D group and the most significant difference observed was at the time 5 minutes after succinylcholine injection. Conclusion:Small doses of oral clonidine as premedicant can effectively reduce the IOP and provide better hemodynamic stability after intravenous injection of succinylcholine and intubation in cataract surgery.

  16. Exercise training prevents increased intraocular pressure and sympathetic vascular modulation in an experimental model of metabolic syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Castro, E.F.S. [Unidade de Hipertensão, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Mostarda, C.T. [Universidade Federal do Maranhão, São Luís, MA (Brazil); Rodrigues, B. [Laboratório do Movimento Humano, Universidade São Judas Tadeu, São Paulo, SP (Brazil); Moraes-Silva, I.C. [Unidade de Hipertensão, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Feriani, D.J. [Laboratório do Movimento Humano, Universidade São Judas Tadeu, São Paulo, SP (Brazil); De Angelis, K. [Laboratório de Fisiologia Translacional, Universidade Nove de Julho, São Paulo, SP (Brazil); Irigoyen, M.C. [Unidade de Hipertensão, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil)

    2015-02-13

    The present study aimed to study the effects of exercise training (ET) performed by rats on a 10-week high-fructose diet on metabolic, hemodynamic, and autonomic changes, as well as intraocular pressure (IOP). Male Wistar rats receiving fructose overload in drinking water (100 g/L) were concomitantly trained on a treadmill for 10 weeks (FT group) or kept sedentary (F group), and a control group (C) was kept in normal laboratory conditions. The metabolic evaluation comprised the Lee index, glycemia, and insulin tolerance test (KITT). Arterial pressure (AP) was measured directly, and systolic AP variability was performed to determine peripheral autonomic modulation. ET attenuated impaired metabolic parameters, AP, IOP, and ocular perfusion pressure (OPP) induced by fructose overload (FT vs F). The increase in peripheral sympathetic modulation in F rats, demonstrated by systolic AP variance and low frequency (LF) band (F: 37±2, 6.6±0.3 vs C: 26±3, 3.6±0.5 mmHg{sup 2}), was prevented by ET (FT: 29±3, 3.4±0.7 mmHg{sup 2}). Positive correlations were found between the LF band and right IOP (r=0.57, P=0.01) and left IOP (r=0.64, P=0.003). Negative correlations were noted between KITT values and right IOP (r=-0.55, P=0.01) and left IOP (r=-0.62, P=0.005). ET in rats effectively prevented metabolic abnormalities and AP and IOP increases promoted by a high-fructose diet. In addition, ocular benefits triggered by exercise training were associated with peripheral autonomic improvement.

  17. The effects of topical tropicamide and systemic medetomidine, followed by atipamezole reversal, on pupil size and intraocular pressure in normal dogs.

    Science.gov (United States)

    Wallin-Håkanson, N; Wallin-Håkanson, B

    2001-03-01

    Twenty normal Golden Retrievers being screeened for eye, hip and elbow diseases were given tropicamide topically and medetomidine systemically. Medetomidine effects were later reversed with systemic atipamezole. Pupil size and intraocular pressure changes were determined. Pupil size increased significantly following tropicamide administration and continued to increase slightly but significantly after medetomidine injection. It was unclear whether the slight increase in pupil size following medetomidine administration was due to continued effect of tropicamide or due to the medetomidine itself. Atipamezole did not influence pupil size. Intraocular pressure (IOP) was not affected by these drugs. Ophthalmic screening examination for inherited disease following tropicamide administration is equally feasible prior to sedation with medetomidine and after reversal with atipamezole, but not during the period of sedation.

  18. Travoprost with sofZia® preservative system lowered intraocular pressure of Japanese normal tension glaucoma with minimal side effects.

    Science.gov (United States)

    Mizoue, Shiro; Nakano, Tadashi; Fuse, Nobuo; Iwase, Aiko; Matsumoto, Shun; Yoshikawa, Keiji

    2014-01-01

    This study aimed to evaluate the effect of travoprost with sofZia® preservative system for lowering the intraocular pressure (IOP) of Japanese normal tension glaucoma (NTG) patients. In this prospective, multicenter, open-label study, Japanese NTG patients with baseline IOPs superficial punctate keratopathy, and adverse events were examined at week 4, 8, and 12 after drug instillation. One-hundred and three of the 107 enrolled patients (baseline IOP =15.2±2.0 mmHg [mean ± standard deviation]) completed the study. The mean IOP value as well as percent reduction was significantly reduced at each visit after travoprost with sofZia® initiation (Psuperficial punctate keratopathy. The cumulative incidence of side effects such as eyelash changes, eyelid pigmentation, and deepening of the upper lid was 47.6%, 27.2%, and 16.5%, respectively. Travoprost preserved with sofZia® effectively lowered the IOP of Japanese NTG patients. It was well tolerated with few discontinuations due to adverse events.

  19. Bimatoprost ophthalmic solution 0.03% lowered intraocular pressure of normal-tension glaucoma with minimal adverse events.

    Science.gov (United States)

    Tsumura, Toyoaki; Yoshikawa, Keiji; Suzumura, Hirotaka; Kimura, Tairo; Sasaki, Satoshi; Kimura, Itaru; Takeda, Ryuji

    2012-01-01

    The aim of this study was to evaluate the efficacy and safety of bimatoprost ophthalmic solution 0.03% (bimatoprost) in Japanese normal-tension glaucoma (NTG) patients with an intraocular pressure (IOP) of 18 mmHg or less. Bimatoprost was instilled into the unilateral conjunctival sac of Japanese NTG patients with a baseline IOP of 18 mmHg or less. The time courses of IOP, conjunctival hyperemia, superficial punctate keratitis, and adverse events were examined at 2, 4, 8, and 12 weeks post bimatoprost instillation. Thirty-two of the 38 enrolled NTG patients (mean age, 64.1 ± 12.6 years; 19 males and 19 females) completed the study, with six patients unable to complete the study (two patients discontinued because of side effects and four patients withdrew). The levels of IOP in the treated eyes were significantly reduced (P superficial punctate keratitis scores were noted between the baseline and each point examined. Eyelash disorder, eyelid pigmentation, and deepening of the upper eyelid sulcus were observed in 28, six, and three eyes, respectively. Bimatoprost effectively lowered the IOP. It was well tolerated in Japanese NTG patients, with few patients having to discontinue because of adverse events.

  20. The effect of hydrogel and silicone hydrogel contact lenses on the measurement of intraocular pressure with rebound tonometry.

    Science.gov (United States)

    Zeri, Fabrizio; Calcatelli, Paolo; Donini, Bernardo; Lupelli, Luigi; Zarrilli, Luciana; Swann, Peter G

    2011-12-01

    To assess the accuracy of intraocular pressure (IOP) measurements using rebound tonometry over disposable hydrogel (etafilcon A) and silicone hydrogel (senofilcon A) contact lenses (CLs) of different powers. The experimental group comprised 36 subjects (19 male, 17 female). IOP measurements were undertaken on the subject's right eyes in random order using a rebound tonometer (ICare). The CLs had powers of +2.00D, -2.00D and -6.00D. Six measurements were taken over each contact lens and also before and after the CLs had been worn. A good correlation was found between IOP measurements with and without CLs (all r≥0.80; phydrogel CLs were significant (psilicone hydrogel CLs were not significant. Rebound tonometry can be reliably performed over silicone hydrogel CLs. With hydrogel CLs, the measurements were lower than those without CLs. However, despite the fact that these differences were statistically significant, their clinical significance was minimal. 2011 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  1. Association of biometric factors with anterior chamber angle widening and intraocular pressure reduction after uneventful phacoemulsification for cataract.

    Science.gov (United States)

    Huang, Guofu; Gonzalez, Eduardo; Lee, Roland; Chen, Yi-Chun; He, Mingguang; Lin, Shan C

    2012-01-01

    To evaluate anterior chamber biometric factors associated with the degree of angle widening and intraocular pressure (IOP) reduction after phacoemulsification. University of California, San Francisco, California, USA. Case series. Anterior chamber parameters obtained by anterior segment coherence tomography were compared preoperatively and 3 months postoperatively. Measurements included the angle opening distance 500 μm anterior to the scleral spur (AOD500), trabecular-iris space area 500 μm from the scleral spur (TISA500), iris curvature (I-Curv), anterior chamber angle (ACA), trabecular-iris space area, anterior chamber volume, anterior chamber width, and lens vault (LV). The study enrolled 73 eyes. The mean patient age was 77.45 years ± 7.84 (SD); 65.75% of patients were women. From preoperatively to 3 months postoperatively, the mean AOD500 increased significantly (0.254 ± 0.105 to 0.433 ± 0.108 mm) and the mean IOP decreased significantly (14.97 ± 3.35 to 12.62 ± 3.37 mm Hg) (Pbiometric factors. Preoperative LV appears to be a significant factor in angle widening and IOP reduction after phacoemulsification. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  2. Modification of hydrophobic acrylic intraocular lens with poly(ethylene glycol) by atmospheric pressure glow discharge: A facile approach

    Energy Technology Data Exchange (ETDEWEB)

    Lin Lin; Wang Yao; Huang Xiaodan [Eye Center, Affiliated Second Hospital, College of Medicine, Zhejiang University, Hangzhou 310009 (China); Xu Zhikang [Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education), Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Yao Ke, E-mail: xlren@zju.edu.cn [Eye Center, Affiliated Second Hospital, College of Medicine, Zhejiang University, Hangzhou 310009 (China)

    2010-10-01

    To improve the anterior surface biocompatibility of hydrophobic acrylic intraocular lens (IOL) in a convenient and continuous way, poly(ethylene glycol)s (PEGs) were immobilized by atmospheric pressure glow discharge (APGD) treatment using argon as the discharge gas. The hydrophilicity and chemical changes on the IOL surface were characterized by static water contact angle and X-ray photoelectron spectroscopy to confirm the covalent binding of PEG. The morphology of the IOL surface was observed under field emission scanning electron microscopy and atomic force microscopy. The surface biocompatibility was evaluated by adhesion experiments with platelets, macrophages, and lens epithelial cells (LECs) in vitro. The results revealed that the anterior surface of the PEG-grafted IOL displayed significantly and permanently improved hydrophilicity. Cell repellency was observed, especially in the PEG-modified IOL group, which resisted the attachment of platelets, macrophages and LECs. Moreover, the spread and growth of cells were suppressed, which may be attributed to the steric stabilization force and chain mobility effect of the modified PEG. All of these results indicated that hydrophobic acrylic IOLs can be hydrophilic modified by PEG through APGD treatment in a convenient and continuous manner which will provide advantages for further industrial applications.

  3. Twenty-four hour intraocular pressure monitoring with the SENSIMED Triggerfish contact lens: effect of body posture during sleep.

    Science.gov (United States)

    Beltran-Agulló, Laura; Buys, Yvonne M; Jahan, Farzana; Shapiro, Colin M; Flanagan, John G; Cheng, Jason; Trope, Graham E

    2017-10-01

    To determine the difference in relative intraocular pressure (IOP) measured by the SENSIMED Triggerfish (TF) contact lens in flat compared with 30° head-up sleeping positions in patients with progressive primary open-angle glaucoma or normotensive glaucoma, based on recent or recurrent disc haemorrhage. Prospective, randomised, cross-over, open-label comparative study. IOP was monitored for 24 hours using TF on two separate sessions. Patients were randomly assigned to sleep flat one night and 30° head-up the other. Outputs in arbitrary units were obtained. Sleep and wake periods were defined as 22:00-6:00 and 8:00-22:00, respectively. Mean TF values during sleep and wake periods and wake-sleep and sleep-wake slopes were calculated for each session. TF output signals were compared between positions. Twelve subjects completed the study. Significant mean positive slopes were noted during the sleep period for both positions (p50% of the subjects requires further investigation to establish whether the increased output values over time are an artefact induced by the TF or a real change in IOP. NCT01351779. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  4. Effect of four irrigation solutions on the intraocular pressure and total bacterial count of the normal eye in dogs

    Directory of Open Access Journals (Sweden)

    Mohammed Ahmed Hamdy Abdelhakiem

    2017-10-01

    Full Text Available There are numerous agents that have been used for irrigation of the ocular tissue from attached foreign bodies, inflammatory exudate and microorganisms. For evaluation of four agents of these irrigation solutions, sixteen clinically healthy dogs of both sexes were used in this study. The dogs were allocated into four equal groups. The right eye of dogs for each group was irrigated 3 times daily for three successive days. The groups were irrigated as following: The first group: ringer’s lactate, the second group: normal saline 0.9%, the third group: boric acid 2% and sodium bicarbonate 1% was used for the fourth group. The left eye was considered control one. The results revealed that the four solutions did not cause any obvious alteration of the eyes and change the intraocular pressure (IOP. According to their effects on the total bacterial count, the four irrigation solutions had not any significant effect. It could be concluded that all of these agents may be used for irrigation of the intact eye and removal of the attached exudate and foreign bodies.

  5. Factors Influencing Intraocular Pressure Changes after Laser In Situ Keratomileusis with Flaps Created by Femtosecond Laser or Mechanical Microkeratome.

    Directory of Open Access Journals (Sweden)

    Meng-Yin Lin

    Full Text Available The aim of this study is to describe factors that influence the measured intraocular pressure (IOP change and to develop a predictive model after myopic laser in situ keratomileusis (LASIK with a femtosecond (FS laser or a microkeratome (MK. We retrospectively reviewed preoperative, intraoperative, and 12-month postoperative medical records in 2485 eyes of 1309 patients who underwent LASIK with an FS laser or an MK for myopia and myopic astigmatism. Data were extracted, such as preoperative age, sex, IOP, manifest spherical equivalent (MSE, central corneal keratometry (CCK, central corneal thickness (CCT, and intended flap thickness and postoperative IOP (postIOP at 1, 6 and 12 months. Linear mixed model (LMM and multivariate linear regression (MLR method were used for data analysis. In both models, the preoperative CCT and ablation depth had significant effects on predicting IOP changes in the FS and MK groups. The intended flap thickness was a significant predictor only in the FS laser group (P < .0001 in both models. In the FS group, LMM and MLR could respectively explain 47.00% and 18.91% of the variation of postoperative IOP underestimation (R2 = 0.47 and R(2 = 0.1891. In the MK group, LMM and MLR could explain 37.79% and 19.13% of the variation of IOP underestimation (R(2 = 0.3779 and 0.1913 respectively. The best-fit model for prediction of IOP changes was the LMM in LASIK with an FS laser.

  6. Age-related changes in biomechanical parameters of the cornea and intraocular pressure in a healthy Turkish population.

    Science.gov (United States)

    Sen, Emine; Elgin, Kadriye Ufuk; Yüksekkaya, Pinar; Tirhiş, Mehmet Hakan; Aksakal, Fatma Nur Baran; Teke, Mehmet Yasin; Oztürk, Faruk

    2014-01-01

    To investigate age-related changes in intraocular pressure (IOP) and biomechanical parameters of the cornea in healthy subjects. There were 404 healthy subjects included prospectively in this study. The subjects were divided into 3 groups (Group 1:93 subjects aged aged between 18 and 59, and Group 3:122 subjects aged ≥ 60). Corneal compensated IOP (IOPCC), Goldmann correlated IOP (IOPg), corneal hysteresis (CH), and corneal resistance factor (CRF) were measured by the Ocular Response Analyzer. When all the study groups were evaluated, a moderately significant negative correlation was found between age and CH and between age and CRF (Spearman's rho = -0.372 and -0.353, respectively; P age-related differences among the 3 groups in terms of IOPg, CH, CRF, and central corneal thickness (P = 0.002, P = 0.000, P = 0.000, P = 0.006). There was no confirmation of any difference of IOPcc among the groups (P = 0.427). The mean values of IOPg, CH, and CRF were lower than the other parameters in Group 3 but no significant differences were determined in IOPcc values in the age groups.

  7. Interaction of cochlin and mechanosensitive channel TREK-1 in trabecular meshwork cells influences the regulation of intraocular pressure.

    Science.gov (United States)

    Carreon, Teresia A; Castellanos, Aida; Gasull, Xavier; Bhattacharya, Sanjoy K

    2017-03-28

    This work was funded by National Institute of Health Grants R01 EY016112, EY015266, and EY014801 and an unrestricted grant to the University of Miami's Bascom Palmer Eye Institute from Research to Prevent Blindness. Financial support from Fight for Sight is gratefully acknowledged. Funding to XG was provided by Instituto de Salud Carlos III, Spain (FIS PI14/00141 and RETIC RD12/0034/0003) and Generalitat de Catalunya (2014SGR1165). In the eye, intraocular pressure (IOP) is tightly regulated and its persistent increase leads to ocular hypertension and glaucoma. We have previously shown that trabecular meshwork (TM) cells might detect aqueous humor fluid shear stress via interaction of the extracellular matrix (ECM) protein cochlin with the cell surface bound and stretch-activated channel TREK-1. We provide evidence here that interaction between both proteins are involved in IOP regulation. Silencing of TREK-1 in mice prevents the previously demonstrated cochlin-overexpression mediated increase in IOP. Biochemical and electrophysiological experiments demonstrate that high shear stress-induced multimeric cochlin produces a qualitatively different interaction with TREK-1 compared to monomeric cochlin. Physiological concentrations of multimeric but not monomeric cochlin reduce TREK-1 current. Results presented here indicate that the interaction of TREK-1 and cochlin play an important role for maintaining IOP homeostasis.

  8. Ahmed Versus Baerveldt Glaucoma Drainage Implantation in Patients With Markedly Elevated Intraocular Pressure (≥30 mm Hg).

    Science.gov (United States)

    Resende, Arthur F; Moster, Marlene R; Patel, Neal S; Lee, Daniel; Dhami, Hermandeep; Pro, Michael J; Waisbourd, Michael

    2016-09-01

    Glaucoma patients with markedly elevated intraocular pressure (IOP) are at risk for developing severe hypotony-related complications. The goal of this study was to compare the surgical outcomes of the Ahmed Glaucoma Valve (AGV) and the Baerveldt Glaucoma Implant (BGI) in this patient population. Patients with preoperative IOP≥30 mm Hg were included. Outcome measures were: (1) surgical failure (IOP>21 mm Hg or AGV group and 38 in the BGI group. The mean±SD follow-up was 2.3±1.6 years for the AGV group and 2.4±1.7 years for the BGI group (P=0.643). Mean preoperative IOP was 38.7±6.5 mm Hg for the AGV group and 40.8±7.6 mm Hg for the BGI group. At the last follow-up, 10 (27.0%) patients failed in the AGV group compared with 6 (15.8%) patients in the BGI group (P=0.379). The BGI group had higher rate of flat or shallow anterior chamber (n=4, 10%) compared with the AGV group (n=0, 0%) (P=0.043). Failure rates of AGV and BGI in patients with IOP≥30 mm Hg were comparable. There were more early hypotony-related complications in the BGI group; however, none were vision threatening. Both glaucoma drainage implants were effective in treating patients with uncontrolled glaucoma in an emergency setting.

  9. Continuous intraocular pressure monitoring with a wireless ocular telemetry sensor: initial clinical experience in patients with open angle glaucoma.

    Science.gov (United States)

    Mansouri, Kaweh; Shaarawy, Tarek

    2011-05-01

    The authors report their initial clinical results with a novel wireless ocular telemetry sensor (OTS) (Sensimed AG, Switzerland) for continuous intraocular pressure (IOP) monitoring in patients with open angle glaucoma. This was a prospective, observational cohort of 15 patients. The OTS is a disposable silicone contact lens with an embedded micro-electromechanical system, which measures changes in corneal curvature induced by variations in IOP. An antenna, mounted around the eye, receives the data, which are then transmitted to a recorder. A signal was recorded in all patients. Thirteen (87%) patients completed 24-h IOP monitoring: one patient discontinued IOP monitoring due to device intolerance, and incomplete recordings were obtained in a second patient due to technical device malfunction. In 9/13 (69%) patients, the highest signals were recorded during the nocturnal period. No serious adverse events were recorded. The OTS shows good safety and functionality to monitor IOP fluctuations in patients over 24 h. This technology has the potential to provide hitherto unobtainable data on the chronobiology of IOP, possibly leading to improved care of glaucoma patients.

  10. [Comparison of dynamic contour tonometry, Goldmann applanation Tonometry and tonopen for measuring intraocular pressure in normal tension glaucoma].

    Science.gov (United States)

    Kurtz, Shimon; Soiberman, Uri; Shemesh, Gabi

    2013-11-01

    Normal tension glaucoma (NTG) is a chronic progressive optic neuropathy, characterized by relatively normal intraocular pressure (IOP) measurements. This study utilized three modalities in the measurement of lOP: dynamic contour tonometry (Pascal-DCT), Goldmann applanation tonometry (GAT) and Tonopen XL. To compare the lOP measurements of the three devices in eyes with NTG. This retrospective study of thirty-three NTG patients (66 eyes) who underwent lOP measurements using the three devices was approved by a local ethics committee. The lOP measurements were stratified according to central corneal thickness (CCT) and corneal curvature (CC). The mean DCT IOP was higher (16.22 +/- 3.04 mmHg) than the mean GAT IOP (13.14 +/- 2.83 mmHg, P IOP (12.76 +/- 3.11 mmHg, P measurements were significantly infLuenced by corneal curvature (P = 0.004 and P measured by GAT or Tonopen XL were consistently lower than by DCT. CC significantly influenced GAT and DCT results.

  11. Measurement of treatment compliance using a medical device for glaucoma patients associated with intraocular pressure control: a survey.

    Science.gov (United States)

    Nordmann, Jean-Philippe; Baudouin, Christophe; Renard, Jean-Paul; Denis, Philippe; Lafuma, Antoine; Laurendeau, Caroline; Jeanbat, Viviane; Berdeaux, Gilles

    2010-07-30

    To identify and characterize treatment compliance profiles of glaucoma patients and evaluate the association with intraocular pressure (IOP). A computerized device (Travalert((R))) that recorded daily instillation times and eye-drop counts was given for 3 months. Patients were declared compliant when at least 2 drops were instilled per day. Compliance rates were calculated for weekdays and weekends, separately, over 8 consecutive weeks. A principal components analysis (PCA) was followed by an ascendant hierarchical classification (AHC) to identify compliance groups. 140 patients were recruited (mean age 65.5 years; 51.8% female) of whom 83.6% had primary open-angle glaucoma with mean IOP 23.9 mmHg before Travalert((R)) use. 60.7% were treated with DuoTrav((R)) (travoprost timolol fixed combination) and 39.3% with travoprost. The PCA identified two axes (compliance and treatment weeks). The AHC identified 3 compliance groups: 'high' (56.6%, approx. 80% compliance), 'medium' (21.2%, approx. 50% compliance), and 'low' (22.1%, approx. 20% compliance). Demographics and glaucoma parameters did not predict low compliance. Final mean IOP was 16.1 mmHg, but higher in the low compliance group (17.7 mmHg, P = 0.02). Compliance measurement by a medical device showed compliance rates IOP control. No demographic or glaucoma variable was associated with low compliance.

  12. Simultaneous Implantation of an Ahmed and Baerveldt Glaucoma Drainage Device for Uncontrolled Intraocular Pressure in Advanced Glaucoma.

    Science.gov (United States)

    Rao, Veena S; Christenbury, Joseph; Lee, Paul; Allingham, Rand; Herndon, Leon; Challa, Pratap

    2017-02-01

    To evaluate efficacy and safety of a novel technique, simultaneous implantation of Ahmed and Baerveldt shunts, for improved control of intraocular pressure (IOP) in advanced glaucoma with visual field defects threatening central fixation. Retrospective case series; all patients receiving simultaneous Ahmed and Baerveldt implantation at a single institution between October 2004 and October 2009 were included. Records were reviewed preoperatively and at postoperative day 1, week 1, month 1, month 3, month 6, year 1, and yearly until year 5. Outcome measures included IOP, best-corrected visual acuity, visual field mean deviation, cup to disc ratio, number of glaucoma medications, and complications. Fifty-nine eyes were identified; mean (±SD) follow-up was 26±23 months. Primary open-angle glaucoma was most common (n=37, 63%). Forty-six eyes (78%) had prior incisional surgery. Mean preoperative IOP was 25.5±9.8 mm Hg. IOP was reduced 50% day 1 (PIOP is markedly reduced postoperative day 1 following double glaucoma tube implantation with effects persisting over postoperative year 1 and up to year 5. Complications were higher than that seen in reports of single shunt implantation, which may be explained by patient complexity in this cohort. This technique may prove a promising novel approach for management of uncontrolled IOP in advanced glaucoma.

  13. The use of the iCare tonometer reduced the need for anesthesia to measure intraocular pressure in children.

    Science.gov (United States)

    Grigorian, Florin; Grigorian, A Paula; Olitsky, Scott E

    2012-12-01

    To determine whether the introduction of iCare rebound tonometry in a pediatric ophthalmology clinic resulted in fewer examinations under anesthesia to evaluate children with glaucoma. The medical records of consecutive glaucoma patients were retrospectively reviewed. The numbers of examinations under anesthesia (EUAs) and office visits that included measurement of intraocular pressure (IOP) were compared for three periods relative to introduction of the Icare (Icare Finland Oy, Helsinki, Finland) rebound tonometer into our clinical practice: before device introduction, learning/transition period, and routine use. A total of 87 subjects were included: 48 subjects met inclusion criteria for the first period; 58 patients met inclusion criteria for the third period (some subjects straddled all three periods). The average patient age for the first period was 4.2 years and 4.9 years (P = 0.3) for the third period. The number of EUAs performed before the introduction of the Icare was 55 and after the introduction of the Icare was 18 (P IOP was measured increased from 34 to 151 (P glaucoma and significantly increased successful IOP measurement in clinic. Copyright © 2012 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

  14. Effects of 25- and 30-degree Trendelenburg positions on intraocular pressure changes during robot-assisted radical prostatectomy.

    Science.gov (United States)

    Nishikawa, Masatomo; Watanabe, Hiromitsu; Kurahashi, Tomofumi

    2017-12-01

    The objective of this study was to assess the effects of 25-degree and 30-degree Trendelenburg positions on intraocular pressure (IOP) changes during robot-assisted radical prostatectomy (RARP). This prospective study involved a total of 30 consecutive patients undergoing RARP. All participants were randomly divided into two groups: Trendelenburg position with the head down at 25 degrees or 30 degrees. In addition to representative operative outcomes, IOP was measured at six discrete time points; Time 1 (T1): before induction of general anesthesia, patients in a horizontal supine position; T2: after induction of general anesthesia, patients in a horizontal supine position; T3: 1 hour after adopting the Trendelenburg position; T4: 2 hours after adopting the Trendelenburg position; T5: after pneumoperitoneum resolution in the Trendelenburg position; T6: anesthetized before awakening in a supine position. The total and console operative times, estimated blood loss, and intravenous fluid intake during RARP did not significantly differ between the two groups. While the IOP values measured at the same time points were similar between the two groups, the 25-degree Trendelenburg position significantly attenuated the IOP change from T1 to T3, T4, and T5 compared with those at 30 degrees. These findings suggest that RARP in the 25-degree Trendelenburg position may reduce the risks of position-related ophthalmic complications without increasing the difficulty of the surgical procedure.

  15. Intraocular pressure and its correlation with midnight plasma cortisol level in Cushing's disease and other endogenous Cushing's syndrome.

    Science.gov (United States)

    Mishra, Priyadarshini; Singh, Alok Pratap; Kanaujia, Vikas; Agarwal, Rachna; Mishra, Prabhaker; Guleria, Ashwani; Tripathi, Alka

    2017-09-01

    The purpose of this study is to measure intraocular pressure (IOP) and evaluate the correlation between IOP and midnight plasma cortisol (MPC) level in patients with Cushing's disease (CD) and other endogenous Cushing's syndrome (ECS). This is a cross-sectional study from a single center including newly diagnosed patients with CD or ECS. All patients underwent detailed ophthalmological evaluation. IOP was measured by Goldmann applanation tonometry in the morning and evening on two consecutive days. MPC value was obtained for each patient. The data were compared using paired and unpaired t-test, Mann-Whitney U-test, and Spearman's rank correlation coefficient. Among 32 patients, 22 were CD (68.75%) and 10 patients were other ECS (31.25%). A total of 25 patients (78.12%) in our study group had normal IOP (correlation was found between IOP and MPC (Spearman's rank correlation rho = -0.16 [P = 0.38]). In CD and ECS patients, IOP elevation is an uncommon feature, and high IOP in either group does not correlate with MPC level.

  16. Changes in intraocular pressure and central corneal thickness during pregnancy: a systematic review and Meta-analysis.

    Science.gov (United States)

    Wang, Chao; Li, Ai-Ling; Pang, Yu; Lei, Ying-Qing; Yu, Ling

    2017-01-01

    To conduct a Meta-analysis for investigating the variations in intraocular pressure (IOP) and central corneal thickness (CCT) during normal pregnancy. We searched for clinical trials published up to November 2015 without language or region restrictions in PubMed, EMBASE, Web of Science, the Cochrane Central Register of Controlled Trials, Ovid, EBSCO, Elsevier, the Chinese Biomedicine Database, WanFang, CNKI, CQVIP and Google Scholar. Studies of the ocular changes observed in pregnant women were selected. The main outcomes were assessed by changes in IOP and CCT. Fifteen studies were included. In subgroup analyses, IOP was significantly decreased during the second MD=-1.53, 95%CI (-2.19, -0.87); P<0.00001, and third MD=-2.91, 95%CI (-3.74, -2.08); P<0.00001 trimesters of pregnancy. CCT was increased during the second MD=10.12, 95%CI (2.01, 18.22); P=0.01, trimester of pregnancy; moreover, during the third trimester of pregnancy, the CCT displayed an increasing trend, but the difference was not significant MD=5.98, 95%CI (-1.11, 13.07); P=0.1. A decrease in IOP is accompanied by an increase in CCT in the second and third trimesters of a normal pregnancy in women.

  17. Determination of reference values for intraocular pressure and Schirmer tear test results in clinically normal domestic donkeys (Equus asinus).

    Science.gov (United States)

    Selk Ghaffari, Masoud; Sabzevari, Amin; Ghamsari, SeyedMehdi; Shad, Hussein

    2017-11-25

    This study was conducted to establish normal reference range for the Schirmer tear test (STT) and intraocular pressure (IOP) in clinically normal donkeys for use in clinical practice. Sixteen adult Ethiopian domestic donkeys were used in this study. Complete ophthalmic examinations were performed without chemical restraint. STT values were evaluated in both eyes of all donkeys using a commercial STT strip. IOP was measured in both eyes with a Tono-Pen Vet (Reichert. USA) without using regional nerve blocks. STT values for all eyes (n=32) were 22.1±6.9 mm/minute with a range of 13-35 mm/minute. Comparison of mean STT values between right (n=16) and left eyes (n=16) showed no differences (P=0.6). Mean ±sd IOP values by applanation tonometry were 17.8±3.7 mmHg (range 13.5-24.5 mmHg). Comparison of mean IOP values between right (n=16) and left eyes (n=16) showed no differences (P=0.7). This initial survey provides means and ranges for IOP and STT values in donkeys. These data will assist veterinary ophthalmologists in more accurate diagnosis and management of ophthalmic diseases in donkeys, including keratoconjunctivitis sicca and glaucoma. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Changes in intraocular pressure and horizontal pupil diameter during use of topical mydriatics in the canine eye

    Science.gov (United States)

    Kovalcuka, Liga; Ilgazs, Agris; Bandere, Dace; Williams, David L.

    2017-01-01

    The objective of this study was to determine the effects of topical 0.5% tropicamide, 1% atropine sulphate and 10% phenylephrine hydrochloride ophthalmic solutions on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in the dog during the first hour after treatment. Forty clinically and ophthalmologically normal canine patients (between the ages of 2 and 6 years) of varying breed and sex were used in this study. Animals were randomly divided into four groups of ten and given one drop of tropicamide, atropine, phenylephrine or saline into one eye. IOP and HPD were measured in both eyes every 5 minutes for 60 minutes. Tropicamide increased IOP by 8.8±4.0 mmHg 35 minutes post-treatment compared to pre-treatment (Ptropicamide occurred at 55 minutes and with atropine at 60 minutes. There were no HPD changes in the contralateral, untreated eye. Topical 10% phenylephrine showed maximal pupil dilation 60 minutes after treatment, but the HPD of the – untreated eye slightly decreased at 15 minutes, but this change only reached statistical significance at 40 min post- treatment (P<0.05). Normal saline showed no influence on IOP or HPD. The drugs investigated here show a significant increase in IOP after mydriatics. PMID:28210543

  19. Transient changes of intraocular pressure and anterior segment configuration after diagnostic mydriasis with 1% tropicamide in children.

    Science.gov (United States)

    Tsai, I-Lun; Tsai, Ching-Yao; Kuo, Li-Lin; Liou, Shiow-Wen; Lin, Shan; Wang, I-Jong

    2012-03-01

    This study investigated the association of transient changes in intraocular pressure (IOP) with changes in the anterior chamber configuration in children after diagnostic mydriasis with 1% tropicamide. In this prospective case-control study, 163 hospital clinic-based samples of unrelated children with or without myopia were enrolled. Complete ophthalmological examinations, including visual acuities, cycloplegic refraction, slitlamp examination, fundus examination, IOP, axial length measurement and Pentacam examination were performed. Lens thickness in emmetropic children was significantly greater than in myopic children of both genders, both before and after mydriasis. In a comparison of the biometric differences before and after mydriasis, IOP was not different, but the lens thickness after mydriasis was significantly less in myopic and emmetropic children of both genders. The mean anterior chamber angle, anterior chamber depth and anterior chamber volume significantly increased after mydriasis in myopic and emmetropic children of both genders. These parameters were not related to the changes of IOP under multiple regression analysis. There were no statistically significant differences between groups in either biometric parameters or anterior chamber configurations. While the present findings do not show a significant change in IOP following mydriasis, there was wide inter-individual variation, with some children showing an increase in IOP of up to 8.0 mmHg and some showing a decrease of a similar amount. This variation suggests that IOP should be monitored when mydriatics or cycloplegics are used in children. © 2011 The Authors. Clinical and Experimental Optometry © 2011 Optometrists Association Australia.

  20. Goldmann applanation tonometry compared with corneal-compensated intraocular pressure in the evaluation of primary open-angle Glaucoma

    Directory of Open Access Journals (Sweden)

    Ehrlich Joshua R

    2012-09-01

    Full Text Available Abstract Background To better understand the role of corneal properties and intraocular pressure (IOP in the evaluation of primary open-angle glaucoma (POAG; and to determine the feasibility of identifying glaucomatous optic neuropathy (GON using IOP corrected and uncorrected for corneal biomechanics. Methods Records from 1,875 eyes of consecutively evaluated new patients were reviewed. Eyes were excluded if central corneal thickness (CCT or Ocular Response Analyzer (ORA measurements were unavailable. Presence or absence of GON was determined based on morphology of the optic disc, rim and retinal nerve fiber layer at the time of clinical examination, fundus photography and Heidelberg Retinal Tomography. Goldmann-applanation tonometry (GAT in the untreated state was recorded and Goldmann-correlated (IOPg and corneal-compensated IOP (IOPcc were obtained using the ORA. Glaucomatous eyes were classified as normal or high-tension (NTG, HTG using the conventional cutoff of 21 mm Hg. One eligible eye was randomly selected from each patient for inclusion. Results A total of 357 normal, 155 HTG and 102 NTG eyes were included. Among NTG eyes, IOPcc was greater than GAT (19.8 and 14.4 mm Hg; p  Conclusions IOPcc may account for measurement error induced by corneal biomechanics. Compared to GAT, IOPcc may be a superior test in the evaluation of glaucoma but is unlikely to represent an effective diagnostic test.

  1. Effect on intraocular pressure of switching from latanoprost and travoprost monotherapy to timolol fixed combinations in patients with normal-tension glaucoma.

    Science.gov (United States)

    Igarashi, Ryoko; Togano, Tetsuya; Sakaue, Yuta; Yoshino, Takaiko; Ueda, Jun; Fukuchi, Takeo

    2014-01-01

    Purpose. To evaluate the effect on intraocular pressure (IOP) of switching from latanoprost and travoprost monotherapy to timolol fixed combinations in Japanese patients with normal-tension glaucoma (NTG). Methods. 27 NTG patients (54 eyes) were compared IOP, superficial punctuate keratitis (SPK) scores, and conjunctival injection scores in eyes treated with prostaglandin (PG) or PG analog/beta-blocker (PG/b) fixed-combination 6 months after the change in therapy. Results. The mean baseline intraocular pressure was 17.4 ± 1.59 mmHg in eyes receiving PG therapy only and 17.4 ± 1.69 mmHg in eyes switched to PG/b. Switching to fixed combination therapy from PG monotherapy, the mean IOP was 13.1 ± 1.79 mmHg (P < 0.001)  (-24.71% reduction from baseline) at 6 months. The mean conjunctival injection score was 0.69 for eyes on PG monotherapy and 0.56 for eyes on fixed combination therapy (P = 0.028). The mean SPK scores were 0.46 and 0.53. This difference was not statistically significant (P = 0.463). Conclusions. Switching from PG monotherapy to PG/b fixed combination therapy for NTG resulted in a greater intraocular pressure reduction than PG alone without increasing the number of instillations.

  2. Effect on Intraocular Pressure of Switching from Latanoprost and Travoprost Monotherapy to Timolol Fixed Combinations in Patients with Normal-Tension Glaucoma

    Directory of Open Access Journals (Sweden)

    Ryoko Igarashi

    2014-01-01

    Full Text Available Purpose. To evaluate the effect on intraocular pressure (IOP of switching from latanoprost and travoprost monotherapy to timolol fixed combinations in Japanese patients with normal-tension glaucoma (NTG. Methods. 27 NTG patients (54 eyes were compared IOP, superficial punctuate keratitis (SPK scores, and conjunctival injection scores in eyes treated with prostaglandin (PG or PG analog/beta-blocker (PG/b fixed-combination 6 months after the change in therapy. Results. The mean baseline intraocular pressure was 17.4±1.59 mmHg in eyes receiving PG therapy only and 17.4±1.69 mmHg in eyes switched to PG/b. Switching to fixed combination therapy from PG monotherapy, the mean IOP was 13.1±1.79 mmHg (P<0.001  (-24.71% reduction from baseline at 6 months. The mean conjunctival injection score was 0.69 for eyes on PG monotherapy and 0.56 for eyes on fixed combination therapy (P=0.028. The mean SPK scores were 0.46 and 0.53. This difference was not statistically significant (P=0.463. Conclusions. Switching from PG monotherapy to PG/b fixed combination therapy for NTG resulted in a greater intraocular pressure reduction than PG alone without increasing the number of instillations.

  3. Effect of Compound Danshen Dripping Pill on circadian blood pressure, high sensitive C reactive protein and cardiac function in patients with non dipper hypertension

    OpenAIRE

    He, Zhi-Wei; Liu, Hui-qin

    2014-01-01

    Objective: To investigate the effect of Compound Danshen Dripping Pill on circadian blood pressure, high sensitive C reactive protein and cardiac function in patients with non dipper hypertension. Methods: According to ABPM nocturnal blood pressure decline rate < 10%, select 178 patients whose systolic pressure and diastolic pressure meet the standards, 88 cases were divided into treatment group, and the rest 90 cases were in control group. All patients were having the levoamlodipine malea...

  4. 21 CFR 886.4270 - Intraocular gas.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraocular gas. 886.4270 Section 886.4270 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4270 Intraocular gas. (a) Identification. An intraocular gas is a device consisting of a gaseous fluid intended to be introduced into the eye to place pressure...

  5. Recovery of canine retina and optic nerve function after acute elevation of intraocular pressure: implications for canine glaucoma treatment.

    Science.gov (United States)

    Grozdanic, Sinisa D; Matic, Milan; Betts, Daniel M; Sakaguchi, Donald S; Kardon, Randy H

    2007-01-01

    To characterize the timing and extent of functional recovery in healthy canine eyes exposed to acute elevation of intraocular pressure (IOP). Acute elevation of IOP was induced in 14 healthy Beagles by elevating IOP above the levels of systolic blood pressure for 60 min (average elevation was between 100 and 160 mmHg). Menace, dazzle and pupillary light reflexes (PLR) were tested at 1, 7, 14 and 28 days post elevation. Optical coherence tomography was used to evaluate retinal thickness preoperatively and at 15 and 30 days post elevation. One day post elevation all animals were blind in the operated eye (no positive menace), 5/14 had positive PLR and 10/14 had positive dazzle response. Seven days post elevation 4/14 animals had positive menace response and all animals (14/14) had positive dazzle and PLR responses. Fourteen and 28 days post elevation all animals had positive menace, PLR and dazzle responses. Optical coherence tomography analysis revealed significant thinning of the inferior retina (pre elevation: 156.3 +/- 4.8 microm; 15 days post elevation: 125 +/- 10.4 microm; 30 days post elevation 123 +/- 11.9 microm; P information about retinal damage after acute elevation of IOP. Canine retina has the capacity to recover at least some visual function even at 14 days after acute elevation of the IOP. More aggressive medical and surgical treatment of canine glaucomatous patients may be indicated despite complete loss of visual function, PLR and dazzle responses in early days after development of an acute glaucomatous attack.

  6. Effects of hemodialysis on corneal and anterior chamber morphometry and intraocular pressure in patients with end-stage renal disease

    Directory of Open Access Journals (Sweden)

    Mehtap Caglayan

    Full Text Available ABSTRACT Purpose: To evaluate the effects of hemodialysis (HD on corneal and anterior chamber morphometry, as well as intraocular pressure (IOP in patients with end-stage renal disease. Methods: Fifty right eyes were examined 30 minutes before and after HD. IOP was measured with a Goldmann applanation tonometer, and Ehlers' formula was used to calculate the corrected IOP values. The central corneal thickness (CCT, corneal volume (CV, keratometric values, anterior chamber depth (ACD, aqueous depth (AQD, anterior chamber volume (ACV, and anterior chamber angle (ACA in the nasal and temporal quadrants were measured with a Sirius anterior segment analysis system. Blood urea nitrogen levels, body mass, and systolic and diastolic arterial pressure were also measured before and after HD. Results: The mean age was 60.80 ± 13.38 (range: 35-80 years. The mean uncorrected and corrected IOP values decreased from 18.06 ± 3.91 and 18.31 ± 4.83 mmHg to 16.94 ± 3.87 and 16.95 ± 4.74 mmHg after HD, respectively (p=0.011 and p=0.003, respectively. The mean CCT decreased from 536.38 ± 24.73 to 533.18 ± 27.25 µm (p=0.002, and the mean CV decreased from 57.52 ± 3.15 to 55.68 ± 3.55 mm³ (p0.05 for all values. There were no significant correlations between the ocular and systemic parameters (p>0.05 for all correlations. Conclusions: Uncorrected IOP, corrected IOP, CCT, and CV values decreased after HD, whereas the anterior chamber morphometry values remained similar between the measurements performed before and after HD.

  7. Importance of intraocular pressure measurement at 6:00 a.m. in bed and in darkness in suspected and glaucomatous patients A importância da medida da pressão intraocular às 6 horas no leito e no escuro em suspeitos e portadores de glaucoma

    Directory of Open Access Journals (Sweden)

    Sebastião Cronemberger

    2010-08-01

    Full Text Available PURPOSE: To assess the importance of intraocular pressure measurement obtained at 6:00 a.m. in bed and darkness for the diagnosis and intraocular pressure control of primary open-angle glaucoma. METHODS: Retrospective analysis of the daily curve of intraocular pressure of suspects and glaucomatous patients under treatment. Suspects were classified as intraocular pressure values ranging from 19 to 24 mmHg in isolated measurements and/or cup/disc ratio > 0.7 in one or both eyes and/or asymmetry of cup/disc ratio > 0.3 and a normal visual field. Each daily curve of intraocular pressure comprised five to seven IOP measurements with Goldmann applanation tonometer at 9:00 a.m., 12:00 p.m., 3:00 and/or 6:00 and 10:00 p.m. and/or 12:00 a.m. and in the following day morning at 6:00 a.m. in supine position in bed and in darkness with Perkins tonometer before the patient had stood up. Only the daily curves of intraocular pressure that presented an intraocular pressure peak (difference between the higher and the lesser intraocular pressure value >6 mmHg were analyzed. In these daily curves, the average intraocular pressure and the standard deviation were calculated. The average intraocular pressure and standard deviation values were compared with the normal superior limits: average + two standard deviation of average intraocular pressure and standard deviation of intraocular pressure daily curve from normal patients of the same age group. Daily curves were considered abnormal when their average intraocular pressure and standard deviation values were above the normal superior limits. Secondary and congenital glaucoma were excluded. RESULTS: Daily curves of intraocular pressure of 565 eyes were analyzed; 361 suspected eyes and 204 eyes with primary open-angle glaucoma. In suspects, 64.3% presented an intraocular pressure peak at 6:00 a.m. in bed. In primary open-angle glaucoma, 68.6% presented an intraocular pressure peak at 6:00 a.m. in bed. In 5.3% of the

  8. Ocular pulse amplitude as a dynamic parameter and its relationship with 24-h intraocular pressure and blood pressure in glaucoma.

    Science.gov (United States)

    Kim, Yoon Jeon; Lee, Kyoung Sub; Lee, Jong Rak; Na, Jung Hwa; Choi, Jaewan; Han, Seungbong; Kook, Michael S

    2013-10-01

    Abnormal ocular blood flow (OBF) has been suspected as one of the underlying mechanisms of glaucoma. The ocular pulse amplitude (OPA) is considered a possible surrogate parameter for ocular blood flow (OBF) measurement and has been studied in its association with glaucoma. Although there have been several studies that reported various ocular and systemic factors in association with OPA, all of these studies were based on a single measurement of these factors as well as OPA. The purpose of this study was to determine the 24-h (h) dynamic variability and any associations between OPA and intraocular pressure (IOP) and blood pressure (BP) variables using 24-h data collected from untreated patients with normal-tension glaucoma (NTG). One hundred and forty-four patients with NTG were consecutively enrolled. All patients underwent 24-h monitoring of IOP, OPA, and BP variables. A cosinor model was used to describe the patterns and statistical significance of the 24-h OPA rhythm, as well as the IOP and BP variables. Associations between 24-h OPA data, IOP and BP variables, and ocular and demographic factors were also assessed using the generalized estimating equation. Over the course of 24-h, OPA (p = 0.007) demonstrated significant dynamic diurnal rhythms that were similar to the other dynamic variables (all p parameter that demonstrates a 24-h short-time fluctuation in NTG patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Age-Related Changes of Intraocular Pressure in Elderly People in Southern China: Lingtou Eye Cohort Study.

    Directory of Open Access Journals (Sweden)

    Xiaotong Han

    Full Text Available To study age-related changes of intraocular pressure (IOP and assess the cohort effect in both cross-sectional and longitudinal settings among elderly Chinese adults.Participants were enrolled from the Lingtou Eye Cohort Study with Chinese government officials aged 40 years and older at baseline and received physical check-up and ocular examinations from 2010 to 2012. IOP was measured using a non-contact tonometer according to standardized protocols, as well as systolic blood pressure (SBP, diastolic blood pressure (DBP and body mass index (BMI. Participants who had attended IOP measurements in both 2010 and 2012 were included in this study. Cross-sectional association of IOP with age was assessed using multivariate liner regression analyses and based on the data of 2010. Longitudinal changes in IOP were assessed by paired t-test.A total of 3372 subjects were enrolled in the current analysis (2010 mean [SD] age, 61.9 [7.1] years; 60.2% men. The mean IOP in 2010 was 15.4 ± 2.3 mmHg for women and 15.2 ± 2.3 mmHg for men with an intersex difference (P = 0.029. Cross-sectional analysis showed that IOP was negatively associated with age (P = 0.003, β = -0.033 for women and P<0.001, β = -0.061 for men adjusted for baseline SBP, DBP and BMI. Paired t-test suggested that IOP was higher in the year 2012 than 2010 in women (P = 0.006 but did not change significantly in men within 2 years (P = 0.345. In addition, the 2-year changes of IOP were not associated with age adjusted for baseline IOP in 2010 (P = 0.249.Cross-sectional data suggests that IOP is lower in people with older age. Longitudinal data does not support such findings and thus the identified decreasing pattern with age in cross-sectional analysis is likely caused by cohort effects.

  10. Fixed combination brimonidine-timolol versus brimonidine for treatment of intraocular pressure elevation after neodymium:YAG laser posterior capsulotomy.

    Science.gov (United States)

    Öner, Veysi; Alakuş, Mehmet Fuat; Taş, Mehmet; Türkyılmaz, Kemal; Işcan, Yalçın

    2012-12-01

    To evaluate the efficacy of fixed combination brimonidine-timolol (FCBT) in comparison with brimonidine tartrate 0.2% and control for the treatment of intraocular pressure (IOP) spikes after neodymium:YAG (Nd:YAG) laser posterior capsulotomy. One hundred five eyes of 105 patients were enrolled in the study. Patients were randomized to 3 groups (each group, including 35 patients): the FCBT group that received 1 drop of FCBT, the brimonidine group that received 1 drop of brimonidine tartrate 0.2%, and the control group that received 1 drop of artificial tear, 1 h before the laser procedure. Postoperative IOP measurements were performed at 1st, 2nd, 3rd, 24th hours, and seventh day. The mean IOP changes from baseline were statistically different between the study groups at first, second, and third hours (all P0.05), the IOP levels of the brimonidine group were less reduced from baseline than the FCBT group at second and third hours (P=0.01 and P=0.03, respectively). The differences among the study groups concerning the incidence of IOP elevations of ≥5 or ≥10 mmHg were statistically significant (P=0.007, P=0.04, respectively). However, the differences between the treatment groups were not statistically significant (both P>0.05). This study has shown that preoperative instillation of 1-drop FCBT was safe and effective for preventing IOP spikes after Nd:YAG laser posterior capsulotomy. FCBT may be a better option than brimonidine tartrate 0.2%, which is one of the current standard prophylaxes for these spikes.

  11. Fixed combination of topical brimonidine 0.2% and timolol 0.5% for glaucoma and uncontrolled intraocular pressure

    Directory of Open Access Journals (Sweden)

    Anne J Lee

    2008-10-01

    Full Text Available Anne J Lee1, Peter McCluskey1,21Department of Ophthalmology, Liverpool Hospital, Liverpool, NSW, Australia; 2Faculty of Medicine, University of New South Wales, Randwick, NSW, AustraliaAbstract: Lowering IOP is the most readily modifiable risk factor to delay the development and progression of glaucoma (POAG. The fixed combination of brimonidine tartrate 0.2% and timolol maleate 0.5% (FCBT combines a highly selective α2-adrenergic agonist (brimonidine with a non-selective β-blocker (timolol. FCBT reduces aqueous production and enhances uveoscleral outflow. Concomitant brimonidine and timolol have additive effects on reducing intraocular pressure (IOP. Multi-center randomized control trials have documented superiority of FCBT twice daily on IOP control compared with monotherapy with the individual components, and equal efficacy compared with concomitant therapy. IOP reduction with FCBT versus fixed combination dorzolamide 2% and timolol 0.5% (FCDT was similar in a small study. Other studies (n > 293 evaluating concomitant brimonidine and timolol have shown that it is not inferior to FCDT. However, concomitant brimonidine and timolol administered twice daily was significantly less efficacious in IOP reduction than fixed combination latanoprost 0.005% and timolol 0.5% (FCLT. There are no published studies comparing FCBT with FCLT. The side effect profile for FCBT reflects that of its individual components. FCBT was generally well tolerated, with less ocular side effects than brimondine alone, but more than timolol alone. Documented systemic effects were few, although this could be confounded by selection bias. FCBT is a safe and effective IOP lowering agent for POAG and ocular hypertension.Keywords: brimonidine, timolol, combigan, glaucoma, combination, ocular hypertension

  12. Effects of premedication with oral gabapentin on intraocular pressure changes following tracheal intubation in clinically normal dogs.

    Science.gov (United States)

    Trbolova, Alexandra; Ghaffari, Masoud Selk; Capik, Igor

    2017-09-19

    Gabapentin is an antiepileptic drug widely approved as an add-on therapy for epilepsy treatment in human and dogs. There is a clinical impression that gabapentin is a suitable drug which attenuates the IOP elevation associated with tracheal intubation in humans. The present study performed to determine the effects of oral gabapentin on intraocular pressure (IOP) changes following tracheal intubation in dogs. Twenty adult healthy dogs were randomly assigned to treatment (n = 10) and control (n = 10) groups. Dogs in the treatment group received oral gabapentin (50 mg/kg) 2 h before induction of anesthesia and dogs in the control group received oral gelatin capsule placebo at the same time. The dogs were anesthetized with propofol 6 mg/kg, and anesthesia was maintained with a constant infusion of 0.2 mg/kg/min of propofol for 20 min. IOP were measured immediately before induction and then repeated immediately after induction, as well as 5 min, 10 min and 15 min following tracheal intubation in both groups. IOP was significantly higher immediately after induction, and 5 min after tracheal intubation when compared with IOP reading before induction in the control group. There was no statistically significant change in IOPs immediately after induction, and 5 min after tracheal intubation in comparison to the values before induction in the treatment group. Based on the findings of this study, preanesthetic oral administration of gabapentin significantly prevents an increase in the IOP associated with tracheal intubation in dogs anesthetized with propofol.

  13. Correlation of endothelin-1 concentration in aqueous humor with intraocular pressure in primary open angle and pseudoexfoliation glaucoma.

    Science.gov (United States)

    Choritz, Lars; Machert, Maren; Thieme, Hagen

    2012-10-23

    Endothelin-1 (ET-1) has been found in elevated concentrations in the aqueous humor of glaucoma patients. Indirect evidence from animal studies suggests that ET-1 might directly influence intraocular pressure (IOP). The aim of this study was to determine whether ET-1 concentrations in aqueous humor of cataract and glaucoma patients correlate with IOP. Aqueous humor and blood samples from patients with either cataract (control, n = 38), primary open angle glaucoma (POAG, n = 35), or pseudoexfoliation glaucoma (PEXG, n = 21), without other ocular or systemic disease, were collected during routine cataract surgery or trabeculectomy. ET-1 concentration was determined by an ET-1 ELISA kit. IOP was measured preoperatively by standard Goldmann applanation tonometry. All statistical analysis was performed using commercial predictive analytics software. Both IOP and ET-1 concentration in aqueous humor were significantly increased in POAG (23.4 ± 6.8 mm Hg, 5.9 ± 2.9 pg/mL) and PEXG (24.3 ± 8.8 mm Hg, 7.7 ± 2.1 pg/mL) compared with control (15.0 ± 2.9 mm Hg, 4.3 ± 2.4 pg/mL). No difference was detected for plasma ET-1 concentrations. IOP and ET-1 in the aqueous humor were significantly correlated (R = 0.394, R² = 0.155, P < 0.001), although no correlation was found between IOP and ET-1 in blood plasma or between ET-1 in aqueous humor and ET-1 in plasma. In this study, a small but highly significant correlation between IOP and the ET-1 concentration in the aqueous humor was found. Although no causative relationship can be deduced from this, ocular ET-1 effects on IOP control may merit further investigation.

  14. Comparison of different intraocular pressure measurement techniques in normal eyes, post surface and post lamellar refractive surgery.

    Science.gov (United States)

    Shousha, Shireen Ma; Abo Steit, Mahmoud Ah; Hosny, Mohamed Hm; Ewais, Wael A; Shalaby, Ahmad Mm

    2013-01-01

    The purpose of this study was to determine the accuracy of intraocular pressure (IOP) measurement after laser in situ keratomileusis (LASIK) or epithelial laser in situ keratomileusis (Epi)-LASIK using Goldmann applanation tonometry, air puff tonometry, ocular response analyzer corneal compensated IOP (ORA IOPcc) and Pentacam corrected IOP. A prospective comparative clinical study was conducted between February and September 2011 on 30 eyes divided into four groups, i.e. 20 corneas of 10 patients before LASIK (group A), 20 corneas of the same patients 2 months postoperatively (group B), 10 corneas of five patients before Epi-LASIK (group C), and 10 corneas of the same patients 2 months postoperatively (group D). Patient age ranged from 20 to 50 years. IOP was measured using Goldmann applanation and air puff tonometry, ORA corneal compensation, and Pentacam correction (which also measured central corneal thickness). Significant positive linear correlations were found between IOP values measured by Goldmann applanation tonometry and other techniques, and with preoperative pachymetry in group A. The correlation between preoperative Pentacam-corrected and preoperative ORA corneal-compensated IOP was strongest for Goldmann applanation tonometry (r = 0.97 and r = 0.858 respectively, P < 0.001). Compared with preoperative values, postoperative IOP measured by the four methods were significantly lower. The difference was statistically significant when IOP was measured using Goldmann applanation and air puff tonometry compared with the ORA and Pentacam methods (P < 0.001 for LASIK patients and P = 0.017 for Epi-LASIK patients). Nonsignificant correlations were found between the degree of lowering of postoperative IOP and postoperative pachymetry in groups B and D. Refractive surgery causes significant lowering of IOP as measured using Goldmann applanation tonometry, air puff tonometry, ORA compensation, and Pentacam correction. LASIK has a greater effect than Epi-LASIK on

  15. Isoflurane and ketamine:xylazine differentially affect intraocular pressure-associated scotopic threshold responses in Sprague-Dawley rats.

    Science.gov (United States)

    Choh, Vivian; Gurdita, Akshay; Tan, Bingyao; Feng, Yunwei; Bizheva, Kostadinka; McCulloch, Daphne L; Joos, Karen M

    2017-10-01

    Amplitudes of electroretinograms (ERG) are enhanced during acute, moderate elevation of intraocular pressure (IOP) in rats anaesthetised with isoflurane. As anaesthetics alone are known to affect ERG amplitudes, the present study compares the effects of inhalant isoflurane and injected ketamine:xylazine on the scotopic threshold response (STR) in rats with moderate IOP elevation. Isoflurane-anaesthetised (n = 9) and ketamine:xylazine-anaesthetised (n = 6) rats underwent acute unilateral IOP elevation using a vascular loop anterior to the equator of the right eye. STRs to a luminance series (subthreshold to -3.04 log scotopic cd s/m 2 ) were recorded from each eye of Sprague-Dawley rats before, during, and after IOP elevation. Positive STR (pSTR) amplitudes for all conditions were significantly smaller (p = 0.0001) for isoflurane- than for ketamine:xylazine-anaesthetised rats. In addition, ketamine:xylazine was associated with a progressive increase in pSTR amplitudes over time (p = 0.0028). IOP elevation was associated with an increase in pSTR amplitude (both anaesthetics p ketamine:xylazine and isoflurane were similar (66.3 ± 35.5 vs. 54.2 ± 24.1 µV, respectively). However, the fold increase in amplitude during IOP elevation was significantly higher in the isoflurane- than in the ketamine:xylazine-anaesthetised rats (16.8 ± 29.7x vs. 2.1 ± 2.7x, respectively, p = 0.0004). The anaesthetics differentially affect the STRs in the rat model with markedly reduced amplitudes with isoflurane compared to ketamine:xylazine. However, the IOP-associated enhancement is of similar absolute magnitude for the two anaesthetics, suggesting that IOP stress and anaesthetic effects operate on separate retinal mechanisms.

  16. Manual suction versus femtosecond laser trephination for penetrating keratoplasty: intraocular pressure, endothelial cell damage, incision geometry, and wound healing responses.

    Science.gov (United States)

    Angunawela, Romesh I; Riau, Andri; Chaurasia, Shyam S; Tan, Donald T; Mehta, Jodhbir S

    2012-05-04

    To measure real-time intraocular pressure (IOP) during trephination with a manual suction trephine (MST) and the femtosecond laser (FSL), and to assess endothelial cell damage, incision geometry, and wound healing response with these procedures. IOP was monitored with an intracameral sensor. Eight rabbits underwent manual suction trephination. Eight rabbits had FSL trephination (FSL-T). Slit lamp photography, confocal microscopy, and anterior segment optical coherence tomography (AS-OCT) were performed at baseline and postoperatively. Animals were sacrificed at 4 hours and 3 days. Tissue was examined with scanning electron microscopy (SEM) and immunohistochemistry for an array of wound-healing markers. Separately, 6 human corneas had MST (3) and FSL-T (3). Incision geometry was imaged with high resolution Optovue AS-OCT. The average IOP during MST and FSL-T was similar (37 mm Hg). There was wider IOP fluctuation during the MST cutting phase (60 mm Hg maximum). There were 1-2 rows of endothelial loss on either side of the incision for FSL-T and 2-5 rows deep for MST. Immune cell responses at 4 hours (CD11b) were comparable, greater apoptosis with FSL-T (TUNEL) occurred at 4 hours, and there was increased keratocyte proliferation at 3 days (Ki67) with FSL-T. There was significantly greater undercutting of the cornea with MST (46.86 degrees versus 16.72 degrees). There is more IOP variation during MST. Average IOP is 37 mm Hg for both techniques. More endothelial damage and undercutting of the cornea occurs with MST. The wound healing response to FSL-T appears greater at 3 days.

  17. Expression-associated polymorphisms of CAV1-CAV2 affect intraocular pressure and high-tension glaucoma risk.

    Science.gov (United States)

    Kim, Sewon; Kim, Kyunglan; Heo, Dong Won; Kim, Jong-Sung; Park, Chan Kee; Kim, Chang-sik; Kang, Changwon

    2015-01-01

    The human CAV1-CAV2 locus has been associated with susceptibility to primary open-angle glaucoma in four studies of Caucasian, Chinese, and Pakistani populations, although not in several other studies of non-Korean populations. In this study with Korean participants, the CAV1-CAV2 locus was investigated for associations with susceptibility to primary open-angle glaucoma accompanied by elevated intraocular pressure (IOP), namely, high-tension glaucoma (HTG), as well as with IOP elevation, which is a strong risk factor for glaucoma. Two single nucleotide polymorphisms (SNPs) were genotyped in 1,161 Korean participants including 229 patients with HTG and 932 healthy controls and statistically examined for association with HTG susceptibility and IOP. One SNP was rs4236601 G>A, which had been reported in the original study, and the other SNP was rs17588172 T>G, which was perfectly correlated (r2=1) with another reported SNP rs1052990. Expression quantitative trait loci (eQTL) analysis was performed using GENe Expression VARiation (Genevar) data. Both SNPs were associated with HTG susceptibility, but the rs4236601 association disappeared when adjusted for the rs17588172 genotype and not vice versa. The minor allele G of rs17588172 was associated significantly with 1.5-fold increased susceptibility to HTG (p=0.0069) and marginally with IOP elevation (p=0.043) versus the major allele T. This minor allele was also associated with decreased CAV1 and CAV2 mRNA in skin and adipose according to the Genevar eQTL analysis. The minor allele G of rs17588172 in the CAV1-CAV2 locus is associated with decreased expression of CAV1 and CAV2 in some tissues, marginally with IOP elevation, and consequently with increased susceptibility to HTG.

  18. Can we measure the intraocular pressure when the eyeball is against the pillow in the lateral decubitus position?

    Science.gov (United States)

    Kim, Ho Soong; Park, Ki Ho; Jeoung, Jin Wook

    2013-11-01

    To evaluate the amount of intraocular pressure (IOP) change in the eye against the pillow in the lateral decubitus position (LDP). Thirty eyes from 15 healthy volunteers (12 men and three women) aged 29 ± 3 (range 25-37) years participated in this study. Using the rebound tonometer (Icare PRO, Icare Finland Oy, Helsinki, Finland), the IOP of both eyes was checked in sitting, supine, right and left LDPs. In the LDP, the additional IOP measurements were taken with the lower eyeball against the latex pillow. Baseline IOP in the sitting position was 12.7 ± 1.9 mmHg in the right eye and 12.8 ± 2.2 mmHg in the left eye. Ten minutes after shifting from the sitting to the supine position, IOP increased significantly (right eye: +1.4 ± 1.4 mmHg, p = 0.006; left eye: +1.8 ± 1.5 mmHg, p = 0.001). Changing from the supine to the right and left LDP increased significantly the IOP of dependent eye (right eye: +2.3 ± 1.8 mmHg, p = 0.001; left eye: +1.5 ± 1.8 mmHg, p = 0.011). When the dependent eye was compressed against the pillow in the LDP, the IOP of the dependent eyes increased significantly after 10 min (right eye in the right LDP: +4.1 ± 4.9 mmHg, p = 0.011; left eye in the left LDP: +3.4 ± 3.7 mmHg, p = 0.006). The IOP was significantly elevated when the eyeball was against the pillow in the LDP. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by Blackwell Publishing Ltd.

  19. The Fluctuation of Intraocular Pressure Measured by a Contact Lens Sensor in Normal-Tension Glaucoma Patients and Nonglaucoma Subjects.

    Science.gov (United States)

    Tojo, Naoki; Abe, Shinya; Ishida, Masaaki; Yagou, Takaaki; Hayashi, Atsushi

    2017-03-01

    We compared the fluctuation of intraocular pressure (IOP) in normal-tension glaucoma (NTG) patients and individuals with nonglaucoma eyes. We obtained continuous IOP values using a SENSIMED Triggerfish contact lens sensor. The eyes of 12 nonglaucoma subjects and 14 NTG patients were examined. In all 26 subjects, the IOP fluctuation was measured continuously for 24 hours with a contact lens sensor. We evaluated the range of IOP fluctuations over the 24-hour period separately for diurnal IOP and nocturnal IOP and identified each subject's maximum value. The range of IOP fluctuation were analyzed, cutoff level of IOP fluctuation was calculated using receiver operating characteristic curve analyses. The mean IOP in the NTG eyes was 11.5±2.4 mm Hg and that in the nonglaucoma eyes was 12.7±2.0 mm Hg, a nonsignificantly difference (P=0.175). The 24-hour range of IOP fluctuations in the NTG group was significantly larger than that of the nonglaucoma group (P=0.007). The percentage of NTG patients who had the peak time of IOP fluctuation during nocturnal sleep was 57.1%, whereas the corresponding rate for the nonglaucoma eyes was 91.7%. The cutoff level of IOP fluctuation for glaucoma was 442 mVeq (sensitivity=1.00; specificity=0.571). The range of IOP fluctuation was larger in the eyes with NTG than in the nonglaucoma eyes. This larger fluctuation might be one of the reasons underlying the aggravation of the visual field by NTG. Measurements of 24-hour continuous IOP might be one of the useful methods to distinguish NTG from nonglaucoma eyes.

  20. Can the SENSIMED Triggerfish(®) lens data be used as an accurate measure of intraocular pressure?

    Science.gov (United States)

    Vitish-Sharma, Parveen; Acheson, Austin G; Stead, Richard; Sharp, John; Abbas, Ali; Hovan, Marta; Maxwell-Armstrong, Charles; Guo, Boliang; King, Anthony J

    2017-04-09

    The SENSIMED Triggerfish(®) contact lens sensor (CLS) has an embedded micro-sensor that captures spontaneous circumferential changes at the corneoscleral junction and transmits them via an antenna to a device where these measurements are stored. During laparoscopic colorectal surgery, patients are placed in Trendelenburg position which has been shown to increase intraocular pressure (IOP). Laparoscopic colorectal surgery requires both pneumoperitoneum and Trendelenburg positioning; therefore, IOP can vary significantly. We aimed to assess whether circumferential changes in the corneoscleral area can be correlated to IOP changes measured using Tono-pen(®) XL applanation tonometer during laparoscopic colorectal surgery. Patients undergoing laparoscopic colorectal resections were included. On the day of surgery, baseline IOP was taken and the SENSIMED Triggerfish(®) CLS was then set up in one eye of the patient. During surgery (whilst under general anaesthetic), IOP measurements were taken in the contralateral eye using a Tono-pen(®) XL applanation tonometer every hour and any time the table was moved to record the fluctuations of IOP during surgery and any association with position change. The timings of these readings were documented. Twenty patients were included in this study (six males, 14 females). Average age was 64.6 years (SD = 16.3). The fluctuation in IOP measured in the reference eye ranged between 6.3 and 46.7 mmHg. The mean correlation coefficient between CLS output measurements and these IOP measurements was r = 0.291 (95% CI). Our results showed a weak correlation between the SENSIMED Triggerfish(®) CLS data output and IOP measurements taken using the Tono-pen(®) XL applanation tonometer. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  1. Comparison of fluctuations of intraocular pressure before and after selective laser trabeculoplasty in normal-tension glaucoma patients.

    Science.gov (United States)

    Tojo, Naoki; Oka, Miyako; Miyakoshi, Akio; Ozaki, Hironori; Hayashi, Atsushi

    2014-01-01

    The aim of this study was to examine the effects of selective laser trabeculoplasty (SLT) treatment on habitual intraocular pressure (IOP) fluctuations in patients with normal-tension glaucoma (NTG) using a SENSIMED Triggerfish contact lens sensor (CLS). Ten patients diagnosed with NTG were enrolled in this study. All patients underwent SLT treatment. Habitual 24-hour IOP fluctuations were recorded before and after SLT. The IOP fluctuations were divided into diurnal periods and nocturnal periods and compared before and after SLT. Changes in corneal thickness and curvature were measured before and after the CLS use with anterior segment optical coherence tomography. The mean IOP was 13.5±2.5 mm Hg before SLT. The mean IOP at 1, 2, and 3 months after SLT was significantly decreased to 10.1±2.3 mm Hg (P=0.002), 11.2±2.7 mm Hg (P=0.0059), and 11.3±2.4 mm Hg (P=0.018), respectively. The range of IOP fluctuations over 24 hours was not significantly changed between before and after SLT treatment (P=0.77). Although the range of IOP fluctuations during the diurnal periods was not significantly changed between before and after SLT treatment (P=0.92), the range of IOP fluctuations during the nocturnal periods significantly decreased from 290±86 mVEq before SLT to 199±31 mVEq after SLT treatment (P=0.014). With respect to corneal changes, the steeper meridian decreased significantly after the CLS use (P=0.016), although other parameters showed no significant difference between before and after the CLS use. SLT treatment was shown to significantly lower IOP and decrease IOP fluctuations during the nocturnal periods in NTG patients. These effects might be important to prevent the progression of NTG.

  2. Fluctuations of the Intraocular Pressure in Pseudoexfoliation Syndrome and Normal Eyes Measured by a Contact Lens Sensor.

    Science.gov (United States)

    Tojo, Naoki; Hayashi, Atsushi; Otsuka, Mitsuya; Miyakoshi, Akio

    2016-05-01

    We compared the fluctuation of the intraocular pressure (IOP) in patients with pseudoexfoliation syndrome (PE) and individuals with normal healthy eyes. We measured continuous IOP using a SENSIMED Triggerfish contact lens sensor (CLS). Eleven eyes with PE and 11 healthy eyes were examined. In all 22 participants, the IOP fluctuation was measured continuously for 24 hours with a CLS. The CLS could measure every 5 minutes. We evaluated IOP fluctuations over the 24-hour period separately for diurnal IOP and nocturnal IOP. We also identified each participant's maximum value. Changes in the corneal thickness and the corneal curvature were measured before and after the CLS use with anterior-segment optical coherence tomography. The mean IOP within the PE eyes was 20.3±3.9 mm Hg and that in the healthy eyes was 13.1±2.1 mm Hg (P<0.001). The 24-hour range of IOP fluctuations in the PE group was significantly larger than that in the healthy group (P=0.004). The central corneal thickness was significantly thicker after CLS use (P=0.011). The steeper meridian changed slightly to myopia (P=0.0068). All healthy eyes had their maximum value during the nocturnal period, whereas 7 of the 11 PE eyes (64%) had their maximum value in the nocturnal period. The IOP fluctuation was larger in the eyes with PE than in the healthy eyes. This larger fluctuation might be one of the reasons underlying the aggravation of the visual field by PE. Measurements of 24-hour continuous IOP might be useful to evaluate IOP fluctuation.

  3. Corneal hysteresis, corneal resistance factor, and intraocular pressure measurements in eyes implanted with a small aperture corneal inlay.

    Science.gov (United States)

    Agca, Alper; Demirok, Ahmet; Celik, Haci Ugur; van de Pol, Corina; Cankaya, Kadir Ilker; Celik, Nimet Burcu; Yasa, Dilek; Yilmaz, Ihsan; Yilmaz, Omer Faruk

    2014-12-01

    To compare the postoperative corneal hysteresis (CH) and corneal resistance factor (CRF) of eyes implanted with a small aperture corneal inlay versus fellow eyes. Medical records of patients who underwent small aperture corneal inlay (KAMRA; AcuFocus, Inc., Irvine, CA) implantation were retrospectively reviewed. There were two groups: the implanted and non-implanted. Main outcome measures were CH, CRF, Goldmann-correlated intraocular pressure (IOPg), corneal-compensated IOP (IOPcc), and Goldmann applanation tonometry measurements performed preoperatively and at postoperative week 1 and months 1, 3, and 6. The study included 68 eyes of 34 patients. CH was higher in the implanted group when compared with the non-implanted group at postoperative week 1 (12.2 ± 3.1 vs 10.9 ± 1.7 mm Hg; P = .007) and month 1 (12.3 ± 2.5 vs 10.9 ± 1.8 mm Hg; P = .001). CRF was higher in the implanted group when compared with the non-implanted group at postoperative week 1 (11.9 ± 2.9 vs 10.7 ± 1.6 mm Hg; P = .003) and month 1 (12.5 ± 2.5 vs 10.4 ± 1.8 mm Hg; P .05). At the 3-month postoperative visit, all parameters had returned to baseline and there was no change at the 6-month visit. Implantation of the KAMRA corneal inlay does not induce a permanent change in CH or CRF. A transient increase in both was seen in the early postoperative period. Copyright 2014, SLACK Incorporated.

  4. Intraocular pressure control and corneal graft survival after implantation of Ahmed valve device in high-risk penetrating keratoplasty.

    Science.gov (United States)

    Almousa, Radwan; Nanavaty, Mayank A; Daya, Sheraz M; Lake, Damian B

    2013-08-01

    To analyze the control of intraocular pressure (IOP) and corneal graft survival after implantation of Ahmed glaucoma device (AGD) in eyes that had high-risk penetrating keratoplasty (PK). This is a retrospective noncomparative case series of 59 eyes that had high-risk PK and underwent AGD insertion. The primary outcome measures are the control of IOP between 6 and 21 mm Hg and corneal graft survival. The secondary outcome measures are risk factors associated with IOP control and corneal graft survival. The mean IOP reduced significantly after the AGD procedure (26.45 ± 6.8 mm Hg preoperatively vs. 16.85 ± 7.4 mm Hg, 16.95 ± 4.6 mm Hg, 17.97 ± 5.7 mm Hg, 15.78 ± 5.2 mm Hg, and 15.59 ± 5.5 mm Hg, at 1 month, 6 months, 1 year, 2 years, and at the last follow-up postoperatively; P IOP control was successful in 44 eyes (75.8%). IOP control was successful in 96% of the eyes at 1 year, 87% at 2 years, 83% at 3 years, and 83% at 5 years. The percentage of clear corneal grafts after 1, 2, 3, and 5 years following the AGD insertion were 87%, 77%, 65%, and 47%, respectively. Further surgery after AGD insertion was associated with 1.79 times greater risk of failure of IOP control. AGD was effective in controlling the IOP associated with high-risk PK over a 5-year period. Postvalve surgery doubles the risk of failure of IOP control.

  5. Effectiveness of the ICare rebound tonometer in patients with overestimated intraocular pressure due to tight orbit syndrome.

    Science.gov (United States)

    Lee, You Kyung; Lee, Y K; Lee, Ji Young; Lee, J Y; Moon, Jung Il; Moon, J I; Park, Myoung Hee; Park, M H

    2014-11-01

    To evaluate the effectiveness of the ICare rebound tonometer in patients with overestimated intraocular pressure (IOP) due to tight orbit syndrome and to identify factors affecting the development of tight orbit syndrome in glaucoma patients. We investigated 84 eyes in 84 glaucoma patients, of which 14 eyes were classified in the tight orbit syndrome group and 70 eyes in the control group. IOP was measured using the ICare tonometer and the Goldmann applanation tonometer (GAT). The demographic data, medical histories, ocular histories, and detailed ocular drug histories of the two groups were compared to identify factors contributing to the development of tight orbit syndrome. In the tight orbit syndrome group, the ICare tonometer significantly underestimated the IOP by approximately 8.6 mmHg compared with the GAT. In the control group, the IOP readings of the GAT and the ICare tonometer did not differ significantly. Bland-Altman analysis showed that the mean difference between measurements taken using the GAT and those taken using the ICare tonometer was 2.5 ± 6.3 mmHg. The difference between the GAT and ICare tonometer measurements was greater in the tight orbit syndrome group (8.6 ± 5.3 mmHg) than in the control group (1.3 ± 2.7 mmHg). Multivariate regression analysis revealed that only the use of prostaglandin analogs (PGAs) was associated with the development of tight orbit syndrome. The ICare tonometer is a suitable alternative device for use in patients with tight orbit syndrome in whom the IOP may be overestimated with the GAT. The prolonged use of PGAs is significantly associated with the development of tight orbit syndrome.

  6. A Comparison of the Corrected Intraocular Pressure Obtained by the Corvis ST and Reichert 7CR Tonometers in Glaucoma Patients.

    Science.gov (United States)

    Nakao, Yoshitaka; Kiuchi, Yoshiaki; Okimoto, Satoshi

    2017-01-01

    The purpose of the study was to investigate the accuracy of two corrected intraocular pressure (IOP) measurements by Corvis Scheimpflug Technology (CST)-IOPpachy and by corneal-compensated IOP (IOPcc) using the Reichert 7CR (7CR) tonometers. We also investigated the effects of corneal anatomical and structural parameters on the IOP measurements. The participants included 90 primary open-angle glaucoma patients. We assessed the IOP measurements, obtained by the CST, 7CR, and Goldmann applanation tonometer (GAT), using a paired t-test with Bonferroni correction, Bland-Altman plots, and multiple regression analyses. The 7CR-IOPcc gave the highest value (15.5 ± 2.7 mmHg), followed by the 7CR-IOPg (13.7 ± 3.1 mmHg), GAT-IOP (13.6 ± 2.2 mmHg), CST-IOP (10.3 ± 2.6 mmHg), and CST-IOPpachy (9.7 ± 2.5 mmHg). The values of CST-IOPpachy were significantly lower than those obtained by the other IOP measurement methods (all, p IOP measurement methods (all, p IOP and the other IOP measurements (CST-IOP, CST-IOPpachy, 7CR-IOPg, and 7CR-IOPcc), which were -3.20, -3.82, 0.14, and 2.00 mmHg, respectively. The widths of the 95% limits of agreement between all pairs of IOP measurements were greater than 3 mmHg. With the exception of the 7CR-IOPcc, all of the IOP variations were explained by regression coefficients involving gender, average corneal curvature, and central corneal thickness. The IOP values obtained by the GAT, CST, and 7CR were not interchangeable. Each new IOP measurement device that was corrected for ocular structure had its own limitations.

  7. [Pachymetry and intraocular pressure measurement by corneal visualization Scheimpflug technology (Corvis ST): A clinical comparison to the gold standard].

    Science.gov (United States)

    Steinberg, J; Mehlan, J; Frings, A; Druchkiv, V; Richard, G; Katz, T; Linke, S J

    2015-09-01

    Analyses regarding accuracy and reproducibility of intraocular pressure (IOP) measurements and pachymetry with corneal visualization Scheimpflug technology (Corvis ST®, CST). Retrospective analysis of 72 eyes with primary open angle glaucoma (POAG) and ocular hypertension (OHT) with no prior surgery or other pathology. The results of Goldmann applanation tonometry (GAT), non-contact tonometry (NCT) and ultrasound pachymetry (USP) were compared with repeat measurements with CST. For statistical analyses the t-test and Bland-Altman plots were applied. The mean IOP was 15.5 ± 4.4 mmHg (CST), 14.8 ± 4.4 mmHg (GAT) and 15.6 ± 4.8 mmHg (NCT). The results of GAT and CST as well as GAT and NCT demonstrated statistically significant differences (p IOP (p = 0.72). The mean differences between the repeat measurements were 0.35 ± 1.7 mmHg (CST) and 0.04 ± 0.85 mmHg (GAT). The mean CST pachymetry results showed 551.3 ± 46.5 µm and the USP 526.5 ± 46.4 µm (p measurements was 24.8 ± 21 µm. No repeat measurement data were available for USP. The CST is a new device for simultaneously measuring the IOP, pachymetry and biomechanical properties of the cornea. Whether the deviations in the IOP measured by CST and CST pachymetry from the manually performed gold standard has to be evaluated as deficient, tolerable or maybe as an improvement, has to be evaluated in further studies. Because of the automated and contact-free measurement method as well as the potential for simultaneously analyzing biomechanical properties of the cornea, the CST is a device that might help the quest for measuring the 'true' IOP.

  8. Effects of inhaled fluticasone on intraocular pressure and central corneal thickness in asthmatic children without a family history of glaucoma.

    Science.gov (United States)

    Alsaadi, Muslim M; Osuagwu, Uchechukwu L; Almubrad, Turki M

    2012-01-01

    The aim of this study is to report the effects of fluticasone-inhaled corticosteroid on intraocular pressure (IOP) and central corneal thickness (CCT) of asthmatic children without a family history of glaucoma. In this prospective study, 93 children were divided into two groups: 69 asthmatic children with no family history of glaucoma who were taking inhaled fluticasone propionate 250 μg daily for at least 6 months (Group 1) and 24 age-matched control subjects without asthma (Group 2). Three measurements each, of IOP and CCT, were performed with a hand-held noncontact tonometer and a noncontact specular microscope, respectively, over a 12-week period. The order of IOP and CCT measured were randomized at each visit. Between-group comparison and the relationship between CCT and IOP measurements were investigated. P IOP was 14 ± 3.3 mmHg (range, 10-24 mmHg) and 14 ± 2.9 mmHg (range, 11-22 mmHg) for Groups 1 and 2, respectively (P = 0.3626). The mean CCT was 531 ± 30.1 μm (range, 467-601 μm) and 519 ± 47.0 μm (range, 415589 μm) for Groups 1 and 2, respectively (P = 0.1625). There was a weak but statistically significant correlation between IOP and CCT in Group 1 (Pearson's R = 0.3580, P = 0.0025). Inhaled fluticasone at the regular dose used in this study over a short period (6-24 months) was not associated with a significant effect on CCT and IOP measured with noncontact devices in asthmatic children between 5 and 15 years, without a family history of glaucoma. A weak correlation between IOP and CCT values in asthmatic children did exist.

  9. Intraocular Pressure Measurements by Three Different Tonometers in Children with Aphakic Glaucoma and a Thick Cornea.

    Science.gov (United States)

    Razeghinejad, Mohammad Reza; Salouti, Ramin; Khalili, Mohammad Reza

    2014-01-01

    To evaluate the agreement in intraocular pressure (IOP) measurements by Ocular Response Analyzer (ORA) and Tono-Pen XL (TXL) with the Goldmann Applanation Tonometer (GAT) and to examine corneal biomechanical properties in aphakic glaucoma patients with a central corneal thickness (CCT) >600 µ. Thirty-six eyes of aphakic glaucoma patients (group 1) and 40 eyes of normal children (group 2) were studied. The mean ORA and TXL IOP values were compared with the GAT-IOP values. Regression analyses were used to evaluate the associations between IOP and CCT, corneal hysteresis (CH), and corneal resistance factor (CRF). Bland-Altman plots were used to evaluate the agreement between the tonometers. The mean±standard deviations of the age and male/female ratio were 16.58±5.44 and 15.75±5.04 years and 14/22 and 18/22 in group 1 and group 2, respectively. CCT in group 1 was 651.1±42 and in group 2 was 567.3±32.4. In group 1, the mean TXL (22.4, P=0.004), IOPcc (corneal compensated) (27.8, P=0.005), and IOPg (Goldmann correlated) values (28.1, PIOP (20.6). In group 2, only IOPg value (16.4) was higher than GAT-IOP (14.8, P=0.04). IOP reading of all the tonometers were positively and negatively associated with CRF and CH in the multiple regression analysis, respectively. The TXL had a greater agreement with the GAT, and the ORA overestimated IOP in aphakic glaucoma patients. The ORA and TXL seemed to be affected by CH and CRF.

  10. Intraocular pressure in children: the effect of body position as assessed by Icare and Tono-Pen tonometers.

    Science.gov (United States)

    Dosunmu, Eniolami O; Marcus, Inna; Tung, Irene; Thiamthat, Warakorn; Freedman, Sharon F

    2014-12-01

    To explore the effect of body position (sitting vs supine) on intraocular pressure (IOP) in children, as assessed by the Icare PRO and the Tono-Pen. Prospective clinical study. Children with known or suspected glaucoma and those without glaucoma were recruited from the Duke Eye Center pediatric clinic. Subjects underwent tonometry in both eyes while upright (sitting), after instillation of topical anesthetic, with either the Icare PRO or the Tono-Pen first, and then the second instrument (order randomized). Goldmann applanation tonometry (GAT) was then performed by a clinician masked to the previous measurements. The subjects were then placed in the supine position for 5 minutes, and tonometry using the Icare PRO and the Tono-Pen was obtained, in the same order used when they were the sitting position. Enrolled were 47 children (94 eyes). Mean seated IOP for GAT, Icare PRO and Tono-Pen were 16.4 ± 4.2, 17.5 ± 3.5, and 18.0 ± 3.9 mm Hg, respectively. The mean supine IOP for the Icare PRO and Tono-Pen were 18.4 ± 4.5 and 18.8 ± 4.2 mm Hg, respectively. This rise was +0.9 ± 2.3 mm Hg for Icare PRO (P = 0.01) and +0.7 ± 1.8 mm Hg for Tono-Pen (P = 0.009), respectively. In children, Icare PRO tonometry correlates well with GAT in the sitting position, and with the Tono-Pen in both the sitting and supine positions. IOP rises when a child changes position from sitting to supine when measured by the Icare PRO or the Tono-Pen. However, the increase, which is less than 1 mm Hg, seems clinically insignificant and is unlikely to alter glaucoma management in children. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Magic Angle–Enhanced MRI of Fibrous Microstructures in Sclera and Cornea With and Without Intraocular Pressure Loading

    Science.gov (United States)

    Ho, Leon C.; Sigal, Ian A.; Jan, Ning-Jiun; Squires, Alexander; Tse, Zion; Wu, Ed X.; Kim, Seong-Gi; Schuman, Joel S.; Chan, Kevin C.

    2014-01-01

    Purpose. The structure and biomechanics of the sclera and cornea are central to several eye diseases such as glaucoma and myopia. However, their roles remain unclear, partly because of limited noninvasive techniques to assess their fibrous microstructures globally, longitudinally, and quantitatively. We hypothesized that magic angle–enhanced magnetic resonance imaging (MRI) can reveal the structural details of the corneoscleral shell and their changes upon intraocular pressure (IOP) elevation. Methods. Seven ovine eyes were extracted and fixed at IOP = 50 mm Hg to mimic ocular hypertension, and another 11 eyes were unpressurized. The sclera and cornea were scanned at different angular orientations relative to the main magnetic field inside a 9.4-Tesla MRI scanner. Relative MRI signal intensities and intrinsic transverse relaxation times (T2 and T2*) were determined to quantify the magic angle effect on the corneoscleral shells. Three loaded and eight unloaded tendon samples were scanned as controls. Results. At magic angle, high-resolution MRI revealed distinct scleral and corneal lamellar fibers, and light/dark bands indicative of collagen fiber crimps in the sclera and tendon. Magic angle enhancement effect was the strongest in tendon and the least strong in cornea. Loaded sclera, cornea, and tendon possessed significantly higher T2 and T2* than unloaded tissues at magic angle. Conclusions. Magic angle–enhanced MRI can detect ocular fibrous microstructures without contrast agents or coatings and can reveal their MR tissue property changes with IOP loading. This technique may open up new avenues for assessment of the biomechanical and biochemical properties of ocular tissues in aging and in diseases involving the corneoscleral shell. PMID:25103267

  12. Magic angle-enhanced MRI of fibrous microstructures in sclera and cornea with and without intraocular pressure loading.

    Science.gov (United States)

    Ho, Leon C; Sigal, Ian A; Jan, Ning-Jiun; Squires, Alexander; Tse, Zion; Wu, Ed X; Kim, Seong-Gi; Schuman, Joel S; Chan, Kevin C

    2014-08-07

    The structure and biomechanics of the sclera and cornea are central to several eye diseases such as glaucoma and myopia. However, their roles remain unclear, partly because of limited noninvasive techniques to assess their fibrous microstructures globally, longitudinally, and quantitatively. We hypothesized that magic angle-enhanced magnetic resonance imaging (MRI) can reveal the structural details of the corneoscleral shell and their changes upon intraocular pressure (IOP) elevation. Seven ovine eyes were extracted and fixed at IOP = 50 mm Hg to mimic ocular hypertension, and another 11 eyes were unpressurized. The sclera and cornea were scanned at different angular orientations relative to the main magnetic field inside a 9.4-Tesla MRI scanner. Relative MRI signal intensities and intrinsic transverse relaxation times (T2 and T2*) were determined to quantify the magic angle effect on the corneoscleral shells. Three loaded and eight unloaded tendon samples were scanned as controls. At magic angle, high-resolution MRI revealed distinct scleral and corneal lamellar fibers, and light/dark bands indicative of collagen fiber crimps in the sclera and tendon. Magic angle enhancement effect was the strongest in tendon and the least strong in cornea. Loaded sclera, cornea, and tendon possessed significantly higher T2 and T2* than unloaded tissues at magic angle. Magic angle-enhanced MRI can detect ocular fibrous microstructures without contrast agents or coatings and can reveal their MR tissue property changes with IOP loading. This technique may open up new avenues for assessment of the biomechanical and biochemical properties of ocular tissues in aging and in diseases involving the corneoscleral shell. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  13. Twenty-Four-Hour Variation of Intraocular Pressure in Primary Open-Angle Glaucoma Treated with Triple Eye Drops

    Directory of Open Access Journals (Sweden)

    Yoshinori Itoh

    2017-01-01

    Full Text Available Objectives. To evaluate 24-hour intraocular pressure (IOP variation in patients with primary open-angle glaucoma (POAG treated with triple eye drops. Subjects and Methods. The IOP was measured in 74 eyes in 74 POAG patients (seated on triple therapy (PG analogue, β-blocker, carbonic anhydrase inhibitor at about every 3 hours. Results. The peak IOP was 13.5 ± 3.1 at 1:00, and the trough IOP was at 12.6 ± 2.4 mmHg at 7:00. The IOP at 7:00 was significantly lower than that at 10:00, 1:00, and 3:00 (p<0.05. Based on the time of the peak IOP, we classified the patients into two groups: diurnal (28 eyes and nocturnal types (37 eyes. There was significant difference at the spherical equivalent between diurnal and nocturnal types (p=0.014. To assess the influence of reflective error, we conducted subanalysis for two groups: high myopic (26 eyes, ≤−6D and low/nonmyopic (24 eyes, ≥−2D groups. In the low/nonmyopia group, the IOP was significantly higher at 1:00 and 3:00 than at 13:00, 16:00, and 7: 00 (p<0.05. Conclusion. The mean of IOP elevated outside of clinic hour in the POAG patients on triple therapy. The low/nonmyopia patient should be carefully treated because the IOP of the patients at night elevated significantly.

  14. Intraocular pressure and its correlation with midnight plasma cortisol level in Cushing's disease and other endogenous Cushing's syndrome

    Directory of Open Access Journals (Sweden)

    Priyadarshini Mishra

    2017-01-01

    Full Text Available Purpose: The purpose of this study is to measure intraocular pressure (IOP and evaluate the correlation between IOP and midnight plasma cortisol (MPC level in patients with Cushing's disease (CD and other endogenous Cushing's syndrome (ECS. Methods: This is a cross-sectional study from a single center including newly diagnosed patients with CD or ECS. All patients underwent detailed ophthalmological evaluation. IOP was measured by Goldmann applanation tonometry in the morning and evening on two consecutive days. MPC value was obtained for each patient. The data were compared using paired and unpaired t-test, Mann–Whitney U-test, and Spearman's rank correlation coefficient. Results: Among 32 patients, 22 were CD (68.75% and 10 patients were other ECS (31.25%. A total of 25 patients (78.12% in our study group had normal IOP (<22 mmHg, and seven patients (21.88% had increased IOP (≥22 mmHg. The percentage of patients with normal IOP was found to be significantly higher compared to percentage of patients with high IOP (P = 0.001 using one-sample Chi-square test. Mean MPC value was 468.6 ± 388.3 nmol/L in patients having IOP ≥22 mmHg and 658.5 ± 584 nmol/L in those with IOP <22 mmHg from both CD and ECS groups, but the difference was not statistically significant. No correlation was found between IOP and MPC (Spearman's rank correlation rho = −0.16 [P = 0.38]. Conclusion: In CD and ECS patients, IOP elevation is an uncommon feature, and high IOP in either group does not correlate with MPC level.

  15. Effect of acute intraocular pressure elevation on the minimum rim width in normal, ocular hypertensive and glaucoma eyes.

    Science.gov (United States)

    Sharma, Sourabh; Tun, Tin A; Baskaran, Mani; Atalay, Eray; Thakku, Sri Gowtham; Liang, Zhang; Milea, Dan; Strouthidis, Nicholas G; Aung, Tin; Girard, Michael Ja

    2018-01-01

    To estimate and compare changes in the Bruch's membrane opening-minimum rim width (BMO-MRW) and area in normal, ocular hypertensive and glaucoma eyes following acute elevations in intraocular pressure (IOP). The optic nerve heads (ONHs) of 104 subjects (31 normals, 20 ocular hypertension (OHT) and 53 with primary glaucoma) were imaged using Spectral-domain optical coherence tomography (OCT; Spectralis, Heidelberg Engineering, Germany). IOP was raised twice by applying a force (0.64 n then 0.9 n) to the anterior sclera using an ophthalmo-dynamometer. After each IOP increment, IOP was held constant, measured with a Tonopen (AVIA applanation tonometer, Reichert, Depew, New York, USA), and ONH was rescanned with OCT. In each OCT volume, BMO-MRW and area were calculated and at each IOP increment. The baseline MRW was significantly smaller in glaucoma subjects (174.3±54.3 µm) compared with normal (287.4±42.2 µm, pglaucoma subjects was significantly thinner at the first and second IOP elevations than that at baseline (both p0.05). Acute IOP elevation leads to compression of the nerve fibre layers of neuroretinal rim in glaucoma subjects only without changing ONH size. This suggests that the neural and connective tissues at ONH level in glaucoma subjects are more susceptible to acute IOP episodes than OHT or normal controls. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. Clinical utility and differential effects of prostaglandin analogs in the management of raised intraocular pressure and ocular hypertension

    Directory of Open Access Journals (Sweden)

    Anne J Lee

    2010-07-01

    Full Text Available Anne J Lee1,2, Peter McCluskey2,31Manchester Royal Eye Hospital, Manchester, UK; 2University of Sydney, Sydney, Australia; 3Sydney Eye Hospital, Sydney, AustraliaAbstract: Prostaglandin analogs (PGA are powerful topical ocular hypotensive agents available for the treatment of elevated intraocular pressure (IOP. Latanoprost 0.005% and travoprost 0.004% are prodrugs and analogs of prostaglandin F2a. Bimatoprost 0.03% is regarded as a prostamide, and debate continues as to whether it is a prodrug. The free acids of all 3 PGAs reduce IOP by enhancing uveoscleral and trabecular outflow via direct effects on ciliary muscle relaxation and remodeling of extracellular matrix. The vast majority of clinical trials demonstrate IOP-lowering superiority of latanoprost, bimatoprost and travoprost compared with timolol 0.5%, brimonidine 0.2%, or dorzolamide 2% monotherapy. Bimatoprost appears to be more efficacious in IOP-lowering compared with latanoprost, with weighted mean difference in IOP reduction documented in one meta-analysis of 2.59% to 5.60% from 1- to 6-months study duration. PGAs reduce IOP further when used as adjunctive therapy. Fixed combinations of latanoprost, bimatoprost or travoprost formulated with timolol 0.5% and administered once daily are superior to monotherapy of its constituent parts. PGA have near absence of systemic side effects, although do have other commonly encountered ocular adverse effects. The adverse effects of PGA, and also those found more frequently with bimatoprost use include ocular hyperemia, eyelash growth, and peri-ocular pigmentary changes. Iris pigmentary change is unique to PGA treatment. Once daily administration and near absence of systemic side effects enhances tolerance and compliance. PGAs are often prescribed as first-line treatment for ocular hypertension and open-angle glaucoma.Keywords: prostaglandin analog, glaucoma, ocular hypertension, latanoprost, bimatoprost, travoprost

  17. Long-term 24-hour intraocular pressure control with travoprost monotherapy in patients with primary open-angle glaucoma.

    Science.gov (United States)

    Riva, Ivano; Katsanos, Andreas; Floriani, Irene; Biagioli, Elena; Konstas, Anastasios G P; Centofanti, Marco; Quaranta, Luciano

    2014-01-01

    The aim of the study was to evaluate the long-term 24-hour intraocular pressure (IOP) efficacy of travoprost monotherapy in primary open-angle glaucoma patients. A total of 36 previously untreated primary open-angle glaucoma patients were enrolled in this 5-year study. Patients underwent an untreated 24-hour IOP evaluation. Subsequently all patients were assigned to topical therapy with travoprost 0.004% eye-drops preserved with benzalkonium chloride (Travatan, Alcon Laboratories Inc., Fort Worth, TX) administered once in the evening (8:00 PM) in both eyes. All patients were then scheduled for a 24-hour IOP assessment approximately 12 months after the baseline visit. This schedule of follow-up was maintained for the whole duration of the trial. The predetermined range of target IOP reduction selected in this cohort of patients ranged between 20% and 30%. A total of 34 patients completed all phases of the investigation. The mean survival time was 57.3±2.0 months and the cumulative survival rate was 0.82±0.6 at 60 months. Travoprost reduced the mean 24-hour IOP from 23.4±1.7 mm Hg at baseline to 16.8±2.4 mm Hg (28.4%), 16.8±2.5 mm Hg (28.1%), 16.8±2.4 mm Hg (28.5%), 16.7±2.5 mm Hg (28.6%), and 16.9±2.4 mm Hg (27.8%), respectively at the end of the first, second, third, fourth, and fifth year follow-up. No drug-related serious adverse events were registered during the study. The present study demonstrated the long-term 24-hour efficacy of travoprost for the treatment of primary open-angle glaucoma.

  18. Effects of Rho Kinase Inhibitors on Intraocular Pressure and Aqueous Humor Dynamics in Nonhuman Primates and Rabbits.

    Science.gov (United States)

    Toris, Carol B; McLaughlin, Marsha A; Dworak, Douglas P; Fan, Shan; Havens, Shane; Zhan, Gui-Lin; Horan, Nicholas; Prasanna, Ganesh

    2016-01-01

    This study examines the effects of 2 Rho kinase inhibitors on intraocular pressure (IOP) and aqueous humor dynamics. IOPs of New Zealand albino rabbits with ocular normotension and cynomolgus macaques (nonhuman primate, NHP) with chronic unilateral laser-induced glaucoma were measured at baseline and periodically after a 9 a.m. dose of H-1152, Y-27632, or vehicle. In a separate group of NHPs, aqueous flow, outflow facility, uveoscleral outflow, and IOP were determined after treatment with Y-27632 or vehicle control. Decreases in IOP were found in rabbits (n = 5) at 6 h after one dose of 2% Y-27632 (29%, P = 0.0002) or 1% H-1152 (35%, P = 0.0001), and in hypertensive eyes of NHPs (n = 7-9) at 3 h after one dose of 2% Y-27632 (35%, P = 0.005) or 1% H-1152 (51%, P = 0.0003). With 2 doses of 1% Y-27632 or vehicle in NHP hypertensive eyes (n = 12), significant drug effects were IOP reduction of 28% (P = 0.05) at 2.5 h after the second dose and increases in aqueous flow (36%; P = 0.013), uveoscleral outflow (59%, P = 0.008), and outflow facility (40%; P = 0.01). In normotensive eyes of the same animals, aqueous flow increased by 21% (P = 0.03). No significant change was found in any of the other parameters. Y-27632 and H-1152 lower IOP in rabbits and hypertensive eyes of NHPs for at least 6 h after single doses. The Y-27632 effect on IOP in hypertensive NHP eyes is caused by increases in outflow facility and uveoscleral outflow. An increase in aqueous humor formation attenuates but does not prevent an IOP decrease.

  19. Changes in intraocular pressure and horizontal pupil diameter during use of topical mydriatics in the canine eye

    Directory of Open Access Journals (Sweden)

    Liga Kovalcuka

    2017-01-01

    Full Text Available The objective of this study was to determine the effects of topical 0.5% tropicamide, 1% atropine sulphate and 10% phenylephrine hydrochloride ophthalmic solutions on intraocular pressure (IOP and horizontal pupil diameter (HPD in the dog during the first hour after treatment. Forty clinically and ophthalmologically normal canine patients (between the ages of 2 and 6 years of varying breed and sex were used in this study. Animals were randomly divided into four groups of ten and given one drop of tropicamide, atropine, phenylephrine or saline into one eye. IOP and HPD were measured in both eyes every 5 minutes for 60 minutes. Tropicamide increased IOP by 8.8±4.0 mmHg 35 minutes post-treatment compared to pre-treatment (P<0.01 only in treated eye. IOP in the contralateral eye did not increase. With atropine the maximum increase in IOP was 2.6±2.8 mmHg at 20 minutes post treatment in the treated eye (P<0.01. IOP in the contralateral eye did not increase. Phenylephrine increased IOP by 2.3±2.1 mmHg (P<0.05 10 minutes after treatment. Also in the untreated eye IOP increased by 2.3±2.1 mmHg, 20 minutes post-treatment. Maximum HPD in eyes treated with tropicamide occurred at 55 minutes and with atropine at 60 minutes. There were no HPD changes in the contralateral, untreated eye. Topical 10% phenylephrine showed maximal pupil dilation 60 minutes after treatment, but the HPD of the – untreated eye slightly decreased at 15 minutes, but this change only reached statistical significance at 40 min post- treatment (P<0.05. Normal saline showed no influence on IOP or HPD. The drugs investigated here show a significant increase in IOP after mydriatics.

  20. Noninvasive measurement of wave speed of porcine cornea in ex vivo porcine eyes for various intraocular pressures.

    Science.gov (United States)

    Zhou, Boran; Sit, Arthur J; Zhang, Xiaoming

    2017-11-01

    The objective of this study was to extend an ultrasound surface wave elastography (USWE) technique for noninvasive measurement of ocular tissue elastic properties. In particular, we aim to establish the relationship between the wave speed of cornea and the intraocular pressure (IOP). Normal ranges of IOP are between 12 and 22mmHg. Ex vivo porcine eye balls were used in this research. The porcine eye ball was supported by the gelatin phantom in a testing container. Some water was pour into the container for the ultrasound measurement. A local harmonic vibration was generated on the side of the eye ball. An ultrasound probe was used to measure the wave propagation in the cornea noninvasively. A 25 gauge butterfly needle was inserted into the vitreous humor of the eye ball under the ultrasound imaging guidance. The needle was connected to a syringe. The IOP was obtained by the water height difference between the water level in the syringe and the water level in the testing container. The IOP was adjusted between 5mmHg and 30mmHg with a 5mmHg interval. The wave speed was measured at each IOP for three frequencies of 100, 150 and 200Hz. Finite element method (FEM) was used to simulate the wave propagation in the corneal according to our experimental setup. A linear viscoelastic FEM model was used to compare the experimental data. Both the experiments and the FEM analyses showed that the wave speed of cornea increased with IOP. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Biomechanical Responses of Lamina Cribrosa to Intraocular Pressure Change Assessed by Optical Coherence Tomography in Glaucoma Eyes.

    Science.gov (United States)

    Quigley, Harry; Arora, Karun; Idrees, Sana; Solano, Francisco; Bedrood, Sahar; Lee, Christopher; Jefferys, Joan; Nguyen, Thao

    2017-05-01

    The purpose of this study was to measure change in anterior lamina cribrosa depth (ALD) globally and regionally in glaucoma eyes at different intraocular pressures (IOP). Twenty-seven glaucoma patients were imaged before and after IOP-lowering procedures using optical coherence tomography. The anterior lamina was marked in approximately 25 locations in each of six radial scans to obtain global and regional estimates of ALD. ALD and its change with IOP were compared with optic disc damage, nerve fiber layer thickness, and visual field loss. Variables associated with deeper baseline ALD included larger cup/disc ratio, thinner rim area, larger cup volume, thinner central corneal thickness, and male sex (all P ≤ 0.02). When IOP was lowered, ALD position became more anterior, more posterior, or was unchanged. The mean ALD change after lowering was 27 ± 142 μm (P = 0.3). The mean absolute value of ALD change was 112 ± 90 μm (P = 0.002). Change in ALD was greater in eyes with lower IOP in paired comparisons (P = 0.006) but was not associated with the magnitude of IOP lowering between imaging sessions (P = 0.94). Eyes with no significant change in ALD tended to have more visual field loss than those with significant anterior ALD displacement (P = 0.07). Areas within each optic nerve head that corresponded to zones with thicker nerve fiber layer had greater ALD positional change (P = 0.0007). The lamina can move either anteriorly or posteriorly with IOP decrease, with greater displacement at lower IOP. Glaucoma eyes and regions within glaucoma eyes associated with greater glaucoma damage exhibited smaller responses.

  2. Measurement of intraocular pressure (IOP) in chickens using a rebound tonometer: quantitative evaluation of variance due to position inaccuracies.

    Science.gov (United States)

    Prashar, A; Guggenheim, J A; Erichsen, J T; Hocking, P M; Morgan, J E

    2007-10-01

    Intraocular pressure (IOP), an important risk factor for glaucoma, is a continuous trait determined by a complex set of genetic and environmental factors that are largely unknown. Genetic studies in laboratory animals may facilitate the identification of genes that affect IOP. We examined the use of the rebound tonometer for measuring IOP in non-anaesthetised birds, along with the device's robustness to alignment errors. Calibration curves were obtained by measuring the IOP of cannulated chicken eyes with the rebound tonometer over a range of pressures. To simulate different types of alignment errors that might be expected with measurement of IOP in alert chickens, for some calibrations the tonometer was positioned (1) at various distances from the cornea, (2) laterally displaced from the visual axis, or (3) angled away from the visual axis. In vivo measurements were taken on three-week-old alert chickens from a layer line, a broiler line, and a layer-broiler "advanced intercross line" (AIL) designed to facilitate QTL mapping. The rebound tonometer showed excellent linearity (R2=0.95-0.99) during calibration, as well as robustness to variation in the probe-to-cornea distance over the range 3-5mm and to lateral displacement over the range 0-2mm. However, the tonometer appeared less robust to off-axis misalignment over the range 0-20 degrees (PIOP measured in non-anaesthetised three-week-old AIL chickens was 17.51+/-0.13 mmHg (mean+/-S.E.; N=105 birds). IOP was significantly associated with corneal thickness (Pmeasurements were necessary in order to gauge IOP accurately in individual birds; a series of seven tonometry sessions over a 12-h period during the light phase of the light/dark cycle permitted IOP to be measured with a 95% CI of +/-0.7 mmHg. IOP did not differ significantly between the broiler and layer chicken lines which served as the progenitor lines for the AIL. In conclusion, the rebound tonometer permits rapid estimation of IOP in chickens and is well

  3. Intraocular pressure and biomechanical corneal properties measure by ocular response analyser in patients with primary congenital glaucoma.

    Science.gov (United States)

    Perucho-González, Lucía; Martínez de la Casa, Jose María; Morales-Fernández, Laura; Bañeros-Rojas, Paula; Saenz-Francés, Federico; García-Feijoó, Julían

    2016-08-01

    To measure the differences in corneal hysteresis (CH) and corneal resistance factor (CRF) in primary congenital glaucoma (PCG) and in control subjects using ocular response analyser (ORA) and also to compare intraocular pressure (IOP) measurements given by ORA against IOP given by Perkins tonometer, a handheld version of Goldman applanation tonometer (GAT), to determine correlation. One hundred and eighteen eyes of 78 patients with PCG (group I) and 103 eyes of 53 controls (group II) were evaluated using ORA. In all participants, IOP was measured using the Perkins tonometer. The ORA device uses applanation pressure peaks to generate the corneal-compensated IOP (IOPcc), which is reportedly independent of corneal thickness, and the measurement of Goldman-correlated IOP (IOPg), which is influenced by corneal thickness. The measures in group I were as follows: IOPcc 20.92 ± 5.33; IOPg 18.87 ± 6.67; CH 8.51 ± 2.25; CRF 9.85 ± 3.03; and IOP measured by Goldman 18.32 ± 5.13. The measures in group II were as follows: IOPcc 14.33 ± 2.91; IOPg 14.77 ± 3.00; CH 11.37 ± 1.61; CRF 11.02 ± 1.74; and IOP measured by Goldman 13.74 ± 2.42. The differences of all parameters compared between both groups were statistically significant (p IOP measures and p = 0.001 for CRF). The values of IOPcc, IOPg and IOP measured with Goldman were higher in group I than the values in group II. However, CH and CRF values were lower in group I. A decrease in CH and CRF has been observed in patients with PCG compared to controls. Future research should assess how these parameters are modified in PCG and whether they could provide more information about progression. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  4. Analysis of the effects of non-supine sleeping positions on the stress, strain, deformation and intraocular pressure of the human eye

    Science.gov (United States)

    Volpe, Peter A.

    This thesis presents analytical models, finite element models and experimental data to investigate the response of the human eye to loads that can be experienced when in a non-supine sleeping position. The hypothesis being investigated is that non-supine sleeping positions can lead to stress, strain and deformation of the eye as well as changes in intraocular pressure (IOP) that may exacerbate vision loss in individuals who have glaucoma. To investigate the quasi-static changes in stress and internal pressure, a Fluid-Structure Interaction simulation was performed on an axisymmetrical model of an eye. Common Aerospace Engineering methods for analyzing pressure vessels and hyperelastic structural walls are applied to developing a suitable model. The quasi-static pressure increase was used in an iterative code to analyze changes in IOP over time.

  5. Estimated Trans-Lamina Cribrosa Pressure Differences in Low-Teen and High-Teen Intraocular Pressure Normal Tension Glaucoma: The Korean National Health and Nutrition Examination Survey.

    Directory of Open Access Journals (Sweden)

    Si Hyung Lee

    Full Text Available To investigate the association between estimated trans-lamina cribrosa pressure difference (TLCPD and prevalence of normal tension glaucoma (NTG with low-teen and high-teen intraocular pressure (IOP using a population-based study design.A total of 12,743 adults (≥ 40 years of age who participated in the Korean National Health and Nutrition Examination Survey (KNHANES from 2009 to 2012 were included. Using a previously developed formula, cerebrospinal fluid pressure (CSFP in mmHg was estimated as 0.55 × body mass index (kg/m2 + 0.16 × diastolic blood pressure (mmHg-0.18 × age (years-1.91. TLCPD was calculated as IOP-CSFP. The NTG subjects were divided into two groups according to IOP level: low-teen NTG (IOP ≤ 15 mmHg and high-teen NTG (15 mmHg < IOP ≤ 21 mmHg groups. The association between TLCPD and the prevalence of NTG was assessed in the low- and high-teen IOP groups.In the normal population (n = 12,069, the weighted mean estimated CSFP was 11.69 ± 0.04 mmHg and the weighted mean TLCPD 2.31 ± 0.06 mmHg. Significantly higher TLCPD (p < 0.001; 6.48 ± 0.27 mmHg was found in the high-teen NTG compared with the normal group. On the other hand, there was no significant difference in TLCPD between normal and low-teen NTG subjects (p = 0.395; 2.31 ± 0.06 vs. 2.11 ± 0.24 mmHg. Multivariate logistic regression analysis revealed that TLCPD was significantly associated with the prevalence of NTG in the high-teen IOP group (p = 0.006; OR: 1.09; 95% CI: 1.02, 1.15, but not the low-teen IOP group (p = 0.636. Instead, the presence of hypertension was significantly associated with the prevalence of NTG in the low-teen IOP group (p < 0.001; OR: 1.65; 95% CI: 1.26, 2.16.TLCPD was significantly associated with the prevalence of NTG in high-teen IOP subjects, but not low-teen IOP subjects, in whom hypertension may be more closely associated. This study suggests that the underlying mechanisms may differ between low-teen and high-teen NTG patients.

  6. Comparing two acromegalic patients with respect to central corneal thickness, intraocular pressure, and tear insulin-like growth factor levels before and after treatment.

    Science.gov (United States)

    Emrah, Kan; Elif, Kilic Kan; Ali, Okuyucu

    2015-09-01

    The aim of the study was to compare the central corneal thickness (CCT), intraocular pressure (IOP), and tear insulin-like growth factor-1 (IGF-1) levels of 2 patients with acromegaly before and after the surgical treatment of the disease. CCTs, IOP levels, and tear IGF-1 values showed a decrease after the treatment in 2 patients. As we found higher CCT, IOP, and tear IGF-1 levels in the active phase of the disease in two acromegaly patients, detailed information about the activity of the disease may be important before the examination of these patients.

  7. A new measure of patient satisfaction with ocular hypotensive medications: The Treatment Satisfaction Survey for Intraocular Pressure (TSS-IOP

    Directory of Open Access Journals (Sweden)

    Stewart Jeanette A

    2003-11-01

    Full Text Available Abstract Purpose To validate the treatment-specific Treatment Satisfaction Survey for Intraocular Pressure (TSS-IOP. Methods Item content was developed by 4 heterogeneous patient focus groups (n = 32. Instrument validation involved 250 patients on ocular hypotensive medications recruited from ophthalmology practices in the Southern USA. Participants responded to demographic and test questions during a clinic visit. Standard psychometric analyses were performed on the resulting data. Sample Of the 412 patients screened, 253 consented to participate, and 250 provided complete datasets. The sample included 44% male (n = 109, 44% Black (n = 109 and 57% brown eyed (n = 142 participants, with a mean age of 64.6 years (SD 13.1 and a history of elevated IOP for an average of 8.4 yrs (SD 7.8. A majority was receiving monotherapy (60%, n = 151. Results A PC Factor analysis (w/ varimax rotation of the 31 items yielded 5 factors (Eigenvalues > 1.0 explaining 70% of the total variance. Weaker and conceptually redundant items were removed and the remaining 15 items reanalyzed. The satisfaction factors were; Eye Irritation (EI; 4 items, Convenience of Use (CofU; 3 items, Ease of Use (EofU; 3 items, Hyperemia (HYP; 3 items, and Medication Effectiveness (EFF; 2 items. Chronbach's Alphas ranged from .80 to .86. Greater distributional skew was found for less common experiences (i.e., HYP & EI with 65% & 48.4% ceilings than for more common experiences (i.e., EofU, CofU, EFF with 10.8%, 20.8% & 15.9% ceilings. TSS-IOP scales converged with conceptually related scales on a previously validated measure of treatment satisfaction, the TSQM (r = .36 to .77. Evidence of concurrent criterion-related validity was found. Patients' symptomatic ratings of eye irritation, hyperemia and difficulties using the medication correlated with satisfaction on these dimensions (r = .30-.56, all p Conclusions This study provides initial evidence that the TSS-IOP is a reliable and valid

  8. Protein expression, biochemical pharmacology of signal transduction, and relation to intraocular pressure modulation by bradykinin B₂ receptors in ciliary muscle.

    Science.gov (United States)

    Sharif, Najam A; Xu, Shouxi; Li, Linya; Katoli, Parvaneh; Kelly, Curtis R; Wang, Yu; Cao, Shutong; Patil, Rajkumar; Husain, Shahid; Klekar, Laura; Scott, Daniel

    2013-01-01

    To examine the bradykinin (BK) B₂-receptor system in human and monkey ciliary muscle (CM) using immunohistochemical techniques, and to pharmacologically characterize the associated biochemical signal transduction systems in human CM (h-CM) cells. BK-induced modulation of intraocular pressure (IOP) in pigmented Dutch-Belt rabbits and cynomolgus monkeys was also studied. Previously published procedures were used throughout these studies. The human and monkey ciliary bodies expressed high levels of B₂-receptor protein immunoreactivity. Various kinins differentially stimulated [Ca²⁺](i) mobilization in primary h-CM cells (BK EC₅₀=2.4±0.2 nM > Hyp³,β-(2-thienyl)-Ala⁵,Tyr(Me)⁸-(®)-Arg⁹-BK (RMP-7) > Des-Arg⁹-BK EC₅₀=4.2 µM [n=3-6]), and this was blocked by B₂-selective antagonists, HOE-140 (IC₅₀=1.4±0.1 nM) and WIN-63448 (IC₅₀=174 nM). A phospholipase C inhibitor (U73122; 10-30 µM) and ethylene glycol tetraacetic acid (1-2 mM) abolished the BK-induced [Ca²⁺](i) mobilization. Total prostaglandin (primarily PGE₂) secretion stimulated by BK and other kinins in h-CM cells was attenuated by the cyclooxygenase inhibitors bromfenac and flurbiprofen, and by the B₂-antagonists. BK and RMP-7 (100 nM) induced a twofold increase in extracellular signal-regulated kinase-1/2 phosphorylation, and BK (0.1-1 µM; at 24 h) caused a 1.4-3.1-fold increase in promatrix metalloproteinases-1-3 release. Topical ocular BK (100 µg) failed to alter IOP in cynomolgus monkeys. However, intravitreal injection of 50 µg of BK, but not Des-Arg⁹-BK, lowered IOP in rabbit eyes (22.9±7.3% and 37.0±5.6% at 5 h and 8 h post-injection; n=7-10). These studies have provided evidence of a functional endogenously expressed B₂-receptor system in the CM that appears to be involved in modulating IOP.

  9. 24-Hour Intraocular Pressure Rhythm in Patients With Untreated Primary Open Angle Glaucoma and Effects of Selective Laser Trabeculoplasty.

    Science.gov (United States)

    Aptel, Florent; Musson, Cécile; Zhou, Thierry; Lesoin, Antoine; Chiquet, Christophe

    2017-03-01

    The purpose of the study was to evaluate the 24-hour nyctohemeral rhythm of intraocular pressure (IOP) in patients with untreated primary open angle glaucoma using a contact lens sensor. To evaluate the effect of selective laser trabeculoplasty (SLT) on the 24-hour rhythm of IOP. Prospective study conducted in a chronobiology center. Fourteen patients with primary open angle glaucoma underwent three 24-hour IOP measurement sessions after a complete wash-out of the medical treatment: before SLT and 1 and 6 months after, using the contact lens sensor Triggerfish (SENSIMED, Lausanne, Switzerland). IOP and the main parameters of nyctohemeral rhythm (existence of a rhythm, acrophase, bathyphase, midline estimating statistic of rhythm, amplitude, and range) before SLT were compared with the same parameters measured 1 and 6 months later. IOP increased from 16.3±3.7 to 22.1±8.4 mm Hg (5.8 mm Hg; 95% confidence interval (CI), 2.41-12.71; P=0.009) after the wash-out procedure. After SLT, IOP significantly decreased by 3.4 mm Hg (95% CI, 0.09-7.89; P=0.041) (14.9%) at 1 month and 1.9 mm Hg (95% CI 0.10-3.84; P=0.044) (8.1%) at 6 months. After medication wash-out, 100% of the subjects had a nyctohemeral IOP rhythm with nocturnal acrophase (01:57±3:32 AM, 01:22±3:01 AM, and 03:17±2:12 AM at inclusion, 1 and 6 mo, respectively). SLT did not significantly change the characteristics of the 24-hour IOP pattern, notably the amplitude and the type of rhythm (persistence of nocturnal acrophase). After medical treatment wash-out, patients with open angle glaucoma consistently had a significant 24-hour IOP rhythm with nocturnal acrophase. SLT reduces the absolute IOP value but does not modify the nyctohemeral IOP rhythm.

  10. Continuous 24-hour Intraocular Pressure Monitoring With a Contact Lens Sensor: Safety, Tolerability, and Reproducibility in Glaucoma Patients

    Science.gov (United States)

    Mansouri, Kaweh; Medeiros, Felipe A.; Tafreshi, Ali; Weinreb, Robert N.

    2013-01-01

    Purpose To determine the safety, tolerability, and reproducibility of intraocular pressure (IOP) patterns during repeated continuous 24-hour IOP monitoring with a telemetric contact-lens sensor (CLS). Design Prospective clinical trial. Participants Forty patients with suspect (n=21) or established glaucoma (n=19). Methods Patients participated in two 24-hour IOP monitoring sessions (S1 and S2) at a 1-week interval using the SENSIMED Triggerfish CLS (Sensimed AG, Switzerland). Patients pursued daily activities and sleep behavior was not controlled. The recordings were analyzed for differences between daytime and nighttime data and for reproducibility of signal patterns between the 2 sessions. Pearson correlations were obtained by pairing intervals across sessions. Main Outcome Measures Adverse events (AE), tolerability using the visual analogue score (VAS), and reproducibility of IOP patterns. Results Mean age was 55.5 ± 15.7 years and 60.0% were male. Main AEs were blurred vision (82.5%), conjunctival hyperemia (80.0%), and superficial punctate keratitis (15.0%). Patients reported a mean VAS of 27.2 ± 18.5 (S1) and 23.8 ± 18.7 (S2) (P = 0.216). Positive linear slopes of the sensor signal from the wake to the sleep period were detected for the ‘no glaucoma medication’ group (slope: 0.14 ± 0.15, p < 0.01, S1; slope: 0.12 ± 0.17, p = 0.03, S2) and for the ‘glaucoma medication’ group (slope: 0.03 ± 0.24, p = 0.52, S1; slope: 0.11 ± 0.16, p = 0.02, S2). Overall correlation between the two sessions was 0.59 (0.51 ‘no glaucoma medication’; 0.63 ‘glaucoma medication’) (P = 0.117). Conclusions Repeated use of the CLS demonstrated good safety and tolerability. The recorded IOP patterns showed fair reproducibility, suggesting that data from 24-h continuous IOP monitoring may be useful in the management of glaucoma patients. PMID:22892888

  11. Twenty-four-hour intraocular pressure related changes following adjuvant selective laser trabeculoplasty for normal tension glaucoma.

    Science.gov (United States)

    Lee, Jacky W Y; Fu, Lin; Chan, Jonathan C H; Lai, Jimmy S M

    2014-12-01

    To investigate intraocular pressure (IOP) related patterns before and after selective laser trabeculoplasty (SLT) for normal tension glaucoma (NTG).In this prospective cohort study, 18 NTG patients underwent SLT. Success was defined as IOP reduction ≥ 20% by Goldmann applanation tonometry. 24-hour IOP-related pattern recording with a contact lens sensor (CLS) (SENSIMED Triggerfish, Sensimed, Switzerland) was done before (baseline) and 1 month after SLT. A cosine function was fitted to the mean CLS patterns for each individual in the SLT success and non-success groups and the amplitude before and after SLT was calculated. Diurnal, nocturnal, and 24-hour CLS pattern local variability was determined for pre- and post-SLT sessions. Cosine amplitude and variability were compared before and after SLT by group using paired t-tests, with α = 0.05. Patients (11 women, 7 men) had a mean age of 65.1 ± 13.7 years. Mean IOP was 15.3 ± 2.2 mm Hg at baseline and was reduced by 17.0% to 12.7 ± 1.8 mm Hg 1 month after SLT (P = 0.001). SLT was successful in 8 patients (44%). The amplitude of the fitted cosine was reduced by 24.6% in the success group, but displayed an amplitude increase of 19.2% post-SLT in the non-success group. Higher diurnal local variability of the CLS pattern was observed after SLT in non-success subjects (P = 0.002), while nocturnal variability showed no significant change. The increase in diurnal variability in the non-success group led to an increase in 24-hour variability in this group (P = 0.001). No change in local variability (diurnal, nocturnal, and 24-hour) was seen in the success group. The IOP-related pattern cosinor amplitude was reduced in NTG patients with a successful SLT treatment whereas the non-success group exhibited an increase of cosine amplitude. Higher diurnal and 24-hour CLS pattern variability was observed in non-success patients 1 month post-SLT.

  12. [Neuroprotective effect of rAAV-mediated rhBDNF gene transfection on rabbit retina against acute high intraocular pressure].

    Science.gov (United States)

    Wang, Jian-ming; Sun, Nai-xue; Hui, Na; Fan, Ya-zhi; Feng, Hai-xiao; Zhao, Shi-ping

    2009-09-01

    To investigate the neuroprotective effect of human brain-derived neurotrophic factor gene transfection into rabbit retina against acute high intraocular pressure (HIOP). Acute HIPO was induced in one eye of 24 white rabbits via saline perfusion into the anterior chamber (model group), and the contralateral eye without treatment served as the control group. In another 24 rabbits, 10 microl recombinant adeno-associated virus (rAAV) vector containing human BDNF gene (rAAV-BDNF) was injected into the vitreous body of one of the eyes 3 days before the operation for HIPO (BDNF group). At 1, 3, 7, and 14 days after HIOP model establishment, 6 eyes in each group were excised to observe the number of retinal ganglion cells (RGCs) and the thickness of the inner retina layer. For the eyes dissected on day 14, electroretinogram b (ERG-b) wave was detected 30 min before (baseline) and on days 1, 3, 7 and 14 after HIOP. Another 5 rabbits were used for ultrastructural observation of the RGCs using transmission electron microscopy, including 1 without treatment, 2 with unilateral HIOP and 2 with rAAV-BDNF transfection before HIOP. The amplitude of ERG-b wave showed no significant difference between the 3 groups before HIOP (P>0.05). In HIOP model group and BDNF group, the amplitude decreased to the lowest at 1 day after HIOP and failed to recover the baseline level at 14 days (P<0.01); at the end of the observation, the amplitude was significantly higher in BDNF group than in the model group (P<0.01). Decreased number of RGCs and thickness of inner retina layer occurred in the model group, but these changes were milder in BDNF group (P<0.05, P<0.01). Electron microscopy revealed ultrastructural changes in the RGCs following acute HIOP, and transfection with rAAV-BDNF ameliorated these changes. rAAV-BDNF transfection protects the retinal structure and improves the amplitude of ERG-b wave after acute high IOP suggesting its neuroprotective effects.

  13. Comparison of Keeler Pulsair EasyEye tonometer and Ocular Response Analyzer for measuring intraocular pressure in healthy eyes

    Science.gov (United States)

    Lopez-De La Fuente, Carmen; Sanchez-Cano, Ana; Ferreras, Antonio; Fuertes-Lazaro, Isabel

    2012-01-01

    Purpose To evaluate the relationship between intraocular pressure (IOP) measurements obtained with Pulsair EasyEye (PEE) and Ocular Response Analyser (ORA) in healthy patients. Methods Sixty-five eyes from 65 patients underwent a full optometric examination, including central corneal thickness (CCT), and IOP measured with PEE and ORA. Differences between IOP measurements between both tonometers were analyzed. Pearson correlation coefficients between IOP values and ORA corneal biomechanics parameters were also obtained. Results Statistically significant differences were found between IOP of PEE (IOPk) and Goldmann-corrected IOP of ORA (IOPg; p = 0.001). IOPk and corneal resistance-corrected IOP of ORA (IOPcc) were also found to differ significantly (p = 0.025). Mean differences between IOPg-IOPk, IOPcc-IOPk and IOPg-IOPcc were 0.71 ± 1.66, 0.70 ± 2.46 and 0.01 ± 1.54 mmHg (mean ± standard deviation), respectively. Pearson correlation coefficients indicated that IOPk, IOPg, and IOPcc were significantly correlated among them (p corneal resistance factor (CRF; r = 0.626 and r = 0.619, respectively) and with CCT (r = 0.531 and r = 0.579, respectively). IOPcc had a linear relationship with corneal hysteresis (CH) (r = −0.482) and similar results were found between CRF and CH (r = 0.841), CRF and CCT (r = 0.681) or between CH and CCT (r = 0.466). Conclusions Differences between mean values of IOP measured with PEE and ORA are statistically significant, with ORA tonometer taking higher IOP values than PEE in most of the cases. IOPk, IOPcc and IOPg have, al least, moderate positive linear correlations and ORA biomechanics parameters CRF, CH and CCT have a linear positive relation between them.

  14. The Icare HOME (TA022) Study: Performance of an Intraocular Pressure Measuring Device for Self-Tonometry by Glaucoma Patients.

    Science.gov (United States)

    Mudie, Lucy I; LaBarre, Sophie; Varadaraj, Varshini; Karakus, Sezen; Onnela, Jouni; Munoz, Beatriz; Friedman, David S

    2016-08-01

    To evaluate the Icare HOME (TA022) device (Icare Oy, Vanda, Finland) for use by glaucoma patients for self-tonometry. Prospective performance evaluation of a medical devic