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Sample records for anterior chamber angle

  1. Foreign Body Embedded in Anterior Chamber Angle

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    Shmuel Graffi

    2012-01-01

    Full Text Available Introduction. We present a case of a metallic foreign body embedded in the anterior chamber angle. After standing in close proximity to a construction worker breaking a tile, a 26-year-old woman using soft contact lens for the correction of mild myopia presented to emergency department for evaluation of a foreign body sensation of her right eye. Methods and Results. Diagnosis was confirmed by gonioscopic examination and a noncontrast CT scan of head and orbits. The foreign body was removed by an external approach without utilizing a magnet. The patient's final outcome was favorable. Discussion. The above is a rare clinical situation, which is impossible to detect on slit-lamp examination without a gonioscopic view. Proper imaging and a specific management are mandatory in order to achieve favorable outcome.

  2. Evaluation of the anterior chamber angle in pseudoexfoliation syndrome.

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    Iwanejko, Małgorzata; Turno-Kręcicka, Anna; Tomczyk-Socha, Martyna; Kaczorowski, Kamil; Grzybowski, Andrzej; Misiuk-Hojło, Marta

    2017-08-01

    Pseudoexfoliation syndrome (PEX) is the most frequently identifiable cause of secondary open-angle glaucoma, known as pseudoexfoliation glaucoma. The exact pathophysiology and etiology of PEX and associated glaucoma remains obscure. The purpose of this study was to determine the differences in the morphology of the anterior chamber angle in people with pseudoexfoliation syndrome and pseudoexfoliation glaucoma compared to a control group. We also evaluated the correlation between intraocular pressure (IOP) and pigmentation of the angle with the amount of exfoliated material in the anterior segment. The study group was composed of 155 eyes from 103 patients aged between 43 and 86 years. Each patient underwent a complete ophthalmological examination. Some difference was found in intraocular pressure between the PEX group and the control group and between the pseudoexfoliation glaucoma group and the control group, but no significant difference was found between the 2 study groups. There was a significant difference in the incidence of some degree of pigmentation in the anterior chamber angle and no difference in the widths of the angle between each group. A significant positive relationship was observed between intraocular pressure and the degree of pigmentation of the anterior chamber angle in both the PEX group and the pseudoexfoliation glaucoma group. The results of this study indicate that the amount of pigmentation and exfoliation material in the anterior segment significantly correlates with the level of IOP and possibly with the degree of trabecular dysfunction. It seems that for clear identification of PEX and pseudoexfoliation glaucoma factors, clinical assessment appears to be insufficient.

  3. Anatomic predictors for anterior chamber angle opening after laser peripheral iridotomy in narrow angle eyes.

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    Huang, Guofu; Gonzalez, Eduardo; Lee, Roland; Osmonavic, Senad; Leeungurasatien, Thidarat; He, Mingguang; Lin, Shan C

    2012-07-01

    To investigate anterior chamber parameters and biometric factors associated with degree of angle opening after laser peripheral iridotomy (LPI) for narrow angles. In this prospective cohort study, patients with narrow angles who were scheduled for LPI were recruited. Anterior chamber parameters by anterior segment coherence tomography (ASOCT) under dark conditions were compared before and after LPI. Only the right eye was used for analysis if both eyes were eligible. Measurements performed by customized software included anterior chamber depth, iris area, angle opening distance at 500 µm (AOD500) anterior to the scleral spur, iris thickness at 750 µm from sclera spur (IT750), trabecular-iris space area 500 (TISA500), and iris curvature (I-Curv). Univariate and multiple regression analyses were performed to determine the predictive factors of angle opening after LPI. Eighty-one patients with narrow angles were prospectively recruited in this study. The AOD500 increased significantly from 0.128 ± 0.081 mm (before) to 0.209 ± 0.087 mm (after) in the nasal quadrant, and from 0.103 ± 0.067 mm (before) to 0.197 ± 0.071 mm (after) in the temporal quadrant (p chamber angle widening after LPI were older age, smaller iris area, and steeper iris.

  4. Dynamic analysis of dark-light changes of the anterior chamber angle with anterior segment OCT.

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    Leung, Christopher Kai-shun; Cheung, Carol Yim Lui; Li, Haitao; Dorairaj, Syril; Yiu, Cedric Ka Fai; Wong, Amy Lee; Liebmann, Jeffrey; Ritch, Robert; Weinreb, Robert; Lam, Dennis Shun Chiu

    2007-09-01

    To describe the use of anterior segment optical coherence tomography (OCT) in studying the dynamic dark-light changes of the anterior chamber angle. Thirty-seven normal subjects with open angles on dark-room gonioscopy and 18 subjects with narrow angles were analyzed. The dynamic dark-light changes of the anterior-chamber angle were captured with real-time video recording. The angle opening distance (AOD500) and trabecular iris space area (TISA500) of the nasal angle and the pupil diameter in each of the representative serial images were measured. Linear regression analysis was performed to investigate the association between AOD500/TISA500 and pupil diameter. Demographic and biometry measurements associated with the AOD difference (AOD500((light)) - AOD500((dark))) and TISA difference (TISA500((light)) - TISA500((dark))) were analyzed with univariate and multivariate regression models. The AOD500/TISA500 measured in the light in the open-angle and the narrow-angle groups were 694 +/- 330 microm/0.24 +/- 0.10 mm(2) and 265 +/- 78 microm/0.10 +/- 0.03 mm(2), respectively. These values were significantly greater than the AOD500/TISA500 measured in the dark (492 +/- 265 microm/0.16 +/- 0.08 mm(2) and 119 +/- 82 microm/0.05 +/- 0.04 mm(2), respectively, all with P chamber depth and the AOD/TISA difference. Fifty eyes showed significant correlations between AOD/TISA and pupil diameter, whereas one eye showed no association. Four eyes in the narrow angle group developed appositional angle closure in the dark. The dynamic dark-light changes of the anterior chamber angle can be imaged and analyzed with anterior segment OCT. Although the angle width generally decreased linearly with increasing pupil diameter, the differences of the angle width measured in the dark and in the light varied substantially among individuals.

  5. Influence of anterior segment biometric parameters on the anterior chamber angle width in eyes with angle closure.

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    Matsuki, Takaaki; Hirose, Fumitaka; Ito, Shin-Ichiro; Hata, Masayuki; Hirami, Yasuhiko; Kurimoto, Yasuo

    2015-02-01

    To predict angle narrowing in eyes with angle closure in a Japanese population using anterior segment optical coherence tomography (AS-OCT) quantitative parameters. AS-OCT was used to examine 118 eyes of 118 patients with angle closure and 40 eyes of 40 patients with open angle under dark conditions. After measuring the angle opening distance 500 (AOD500), anterior chamber depth, iris thickness (IT), iris convexity (IC), pupil diameter, anterior chamber width, and crystalline lens rise, multivariate regression analyses were performed for the AOD500 in each group. With the exception of IT, significant differences were observed between the AS-OCT parameters for the angle closure and open-angle groups. Anterior chamber depth, IT, and IC were the explanatory variables associated with AOD500 for each group (P≤0.001). A significant negative association was found between IT and IC only in the angle-closure group (Pchamber depth was a major mechanism of angle narrowing, and that both IT and IC had a strong impact on angle narrowing. Moreover, the negative association found between IT and IC in only the angle closure group indicated the existence of the stretch force placed on the iris by relative pupillary block.

  6. [Comparison of anterior chamber angle examination by UBM, SL-OCT and gonioscopy].

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    Liu, Rui-jue; Wang, Men; Xia, Wen-tao; Yu, Xiao-ying; Chen, Jie-min; Zhou, Shu; Peng, Shu-ya; Liu, Dong-mei

    2014-08-01

    To compare the agreement of anterior chamber angle examination by ultrasound biomicroscope (UBM), slit lamp optical coherence tomography (SL-OCT), and gonioscopy in angle recession and angle closure. The anterior chamber angle was measured with UBM, SL-OCT and gonioscopy in turns for temporal, nasal, superior and inferior quadrant in the same dark room. The results were compared with the agreement of the three methods in angle recession and angle closure by χ2 test and Kappa test. There were no statistically significant differences of the three methods in testing angle closure and angle recession (P>0.05). The consistency of UBM and gonioscopy was better (Kappa value of 0.882) than that of SL-OCT and gonioscopy (Kappa value of 0.624). When testing angle recession, UBM is better than SL-OCT with gonioscopy as the standard. When testing angle closure, UBM, SL-OCT and gonioscopy have good agreement.

  7. Comparison of Mydriatic Provocative and Dark Room Prone Provocative Tests for Anterior Chamber Angle Configuration.

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    Yamada, Rika; Hirose, Fumitaka; Matsuki, Takaaki; Kameda, Takanori; Kurimoto, Yasuo

    2016-06-01

    To investigate the relationship between angle configuration and diagnostic provocation tests such as the mydriatic provocative test (MPT) and the dark room prone provocative test (DRPPT). Seventy eyes of 70 consecutive patients with primary angle closure suspect, primary angle closure, or primary angle closure glaucoma were included. The anterior chamber depth, angle opening distance 500, trabecular-iris space area 500, and iris thickness (IT) were quantitatively determined by anterior segment optical coherence tomography, and the MPT and DRPPT were used to investigate intraocular pressure variations. Seven eyes were positive and 3 eyes were suspected positive, using the MPT, whereas 10 eyes were positive and 7 eyes were suspected positive using the DRPPT. The anterior chamber depth and angle opening distance 500 of the positive and suspected positive groups (positive group), using the MPT, were significantly less than those of the negative group (P=0.013, P=0.013, respectively). IT of the positive group, using the MPT, was significantly greater than the negative group, using the same test (P=0.003). The trabecular-iris space area 500 of the positive group was significantly less than the negative group, using both the MPT (Pchamber, narrower angle, and greater IT than those from the negative group. These results suggested that the MPT results better correlated with the anterior chamber angle configuration in eyes with primary angle closure, than the results using the DRPPT.

  8. Evaluation of anterior chamber angle under dark and light conditions in angle closure glaucoma: An anterior segment OCT study.

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    Masoodi, Habibeh; Jafarzadehpur, Ebrahim; Esmaeili, Alireza; Abolbashari, Fereshteh; Ahmadi Hosseini, Seyed Mahdi

    2014-08-01

    To evaluate changes of nasal and temporal anterior chamber angle (ACA) in subjects with angle closure glaucoma using Spectralis AS-OCT (SAS-OCT) under dark and light conditions. Based on dark-room gonioscopy, 24 subjects with open angles and 86 with narrow angles participated in this study. The nasal and temporal angle opening distance at 500 μm anterior to the scleral spur (AOD500), nasal and temporal ACA were measured using SAS-OCT in light and dark conditions. In 2 groups, ACA and AOD500 in nasal and temporal quadrants were significantly greater in light compared to dark (all with p=0.000). The AOD500 and ACA were significantly higher in nasal than temporal in measured conditions for 2 groups except the ACA and AOD500 of normal group measured in light. The difference between nasal and temporal in dark (29.07 ± 65.71 μm for AOD500 and 5.7 ± 4.07° for ACA) was greater than light (24.86 ± 79.85 μm for AOD500 and 2.09 ± 7.21° for ACA) condition. But the difference was only significant for ACA (p=0.000). The correlation analysis showed a negative correlation between AOD500 and pupil diameter in temporal and nasal quadrants (both with p=0.000). While temporal AOD500 difference correlated with spherical equivalent, temporal and asal gonioscopy, nasal AOD correlated with IOP, temporal and nasal gonioscopy. Clinically important changes in ACA structure could be detected with SAS-OCT in nasal and temporal quadrants under different illumination intensity. The results could help in improvement of examination condition for better and more accurate assessment of individuals with angle closure glaucoma. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  9. Light-dark changes in iris thickness and anterior chamber angle width in eyes with occludable angles.

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    Hirose, Fumitaka; Hata, Masayuki; Ito, Shin-ichiro; Matsuki, Takaaki; Kurimoto, Yasuo

    2013-10-01

    The purpose of this study was to investigate and measure light-dark changes in iris thickness (IT) and anterior chamber angle width in eyes with occludable angles and open angles by using anterior segment optical coherence tomography (AS-OCT). We examined 153 eyes of 153 Japanese patients with primary angle closure suspect, primary angle closure, primary angle closure glaucoma, or primary open angle glaucoma. AS-OCT was used to determine pupil diameter, IT, angle opening distance at 500 μm (AOD₅₀₀), and trabecular-iris space area at 500 μm (TISA₅₀₀) in each quadrant of the anterior chamber angle (superior, inferior, temporal, and nasal) under light and dark conditions. In the angle closure cases, IT, AOD₅₀₀ and TISA₅₀₀ in the dark varied significantly among the four quadrants (P dark did not differ significantly among the four quadrants. In the angle closure cases and the open angle cases, significant negative associations were found between IT difference [IT(light)-IT(dark)] and AOD₅₀₀ difference [AOD₅₀₀(light)-AOD₅₀₀(dark)] (R = -0.411, P dark)] (R = -0.475, P dark conditions is related to the mechanism of primary angle closure. It is important to analyze both the angle structure and peripheral IT in each quadrant.

  10. The effect of internal fixation lamp on anterior chamber angle width measured by anterior segment optical coherence tomography.

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    Nakamine, Sakari; Sakai, Hiroshi; Arakaki, Yoshikuni; Yonahara, Michiko; Kaiya, Tadayoshi

    2018-01-01

    To study the effect of the internal fixation lamp on anterior chamber width measured by anterior segment optical coherence tomography. In a prospective cross sectional observational study, consecutive 22 right eyes of 22 patients (4 men and 18 women) with suspected primary angle closure underwent swept source domain anterior segment optical coherence tomography (AS-OCT), (CASIA SS-1000, Tomey, Nagoya, Japan). Anterior chamber parameters of angle opening distance (AOD), trabecular-iris angle (TIA), angle recess area (ARA) at 500 or 750 µm from scleral spur and pupil diameter were measured by AS-OCT in a three-dimensional mode in 4 quadrants (superior, inferior, temporal and nasal) in dark room setting both with and without internal fixation lamp. Anterior segment parameters of AOD 500 in superior, inferior and temporal quadrants, AOD 750 at superior and nasal, TIA 500 at superior, and inferior and TIA 750 at superior and nasal, and ARA 500 or 750 at superior and inferior with internal fixation lamp were greater and the pupil diameter was significantly (all P chamber angle is narrow but open, it is recommended that the internal fixation lamp be turned off to ensure a clear indication as to whether the angle is open or closed in the dark.

  11. [Analysis of anatomy features for patients with narrow anterior chamber angle and primary iridociliary body cysts].

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    Li, Gui-gang; Ji, Cai-ni; Li, Xin-yu; Hu, Wei-kun; Hu, Jun; Wang, Jun-ming; Li, Tao; Li, Bin; Zhang, Hong

    2012-08-01

    To investigate the prevalence and anatomy features of iridociliary body cysts in patients with narrow anterior chamber angle. Retrospective case series study. The prevalence and anatomy features of iridociliary body cysts in 223 patients (402 eyes) were analyzed retrospectively with ultrasound biomicroscopy (UBM). All of the patients were examined for susceptive narrow anterior chamber angle without complaint. The age of the patients, the site, diameter and number of cysts, the anterior chamber angle and the central anterior chamber depth were measured. Iridociliary body cysts were found in 19 patients (23 eyes) out of 223 patients (402 eyes), the prevalence is 5.7%. Fifteen patients were unilateral and four patients bilateral. Two cases originated from the ciliary process, eighteen cases from the iris root, and three from both the root and posterior surface of the iris. Twenty one cases were single cysts while two cases were multiple cysts. The diameter of the cysts ranged from 0.5 to 3.1 mm, averaged (0.71 ± 0.53) mm. The average age and the central anterior chamber depth of the eyes with iridociliary body cysts were (55.32 ± 10.74) years and (2.25 ± 0.39) mm, with no significant difference (t = 0.534, 0.783; P > 0.05) as compared to that of patients without cysts, which were (57.46 ± 10.52) years and (2.14 ± 0.34) mm. The anterior chamber angle in iridociliary body cysts group was 8.2° (21.0°, 0.0°), with no significant difference (Z = -0.062, P > 0.05) as compared to that of patients without cysts, which was 8.9° (21.4°, 0.0°). The prevalence rate of iridociliary body cysts in this study is 5.7%, central anterior chamber depth and anterior chamber angle in patients with cysts do not differ form patients without cysts.

  12. [Experimental hypertony caused by obstruction of the anterior chamber angle ab interno (author's transl)].

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    Maguritsas, N; Vikas, C; Theodossiadis, G; Vergados, I; Velissaropoulos, P

    1976-07-01

    In 30 rabbits, separated into 3 groups (A, B and C), the entire area (A), three quarters (B) half of the anterior chamber angle (C) was experimentally obstructed by means of a homologous scleral graft. In groups A and B a statistically significant change of the intraocular pressure and of the cornea diameter was shown as compared with the control eye and group C. This change is due to the obstructed area of the angle. The increased intraocular pressure lasted for some months. The graft was well tolerated by the tissue of the angle and the obstruction of the angle was total, as was confirmed by means of the histological preparations.

  13. Changes in ocular biometry and anterior chamber parameters after pharmacologic mydriasis and peripheral iridotomy in primary angle closure suspects

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    Mohammad Reza Razeghinejad

    2016-07-01

    Conclusions: This study showed no change in the ocular biometric and anterior chamber parameters including iridocorneal angle after PI and/or pharmacologic mydriasis except for increments in anterior chamber volume. This factor has the potential to be used as a numerical proxy for iris position in evaluating and monitoring patients with primary angle closure suspects after PI.

  14. Measurements of anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter using two Scheimpflug imaging devices

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    Alberto Domínguez-Vicent

    2014-08-01

    Full Text Available Purpose: To compare the ocular anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter, as measured with two different Scheimpflug imaging devices. Methods: This transversal study included 80 right eyes from 80 subjects aged from 20 to 40 years. Their spherical equivalents ranged from -4.25 to +1.00 diopters (D. Each eye's anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter, were measured for far vision using both the Galilei G4 (double Scheimpflug camera and the Pentacam HR (single Scheimpflug camera systems. Results: Mean anterior chamber depths were calculated as 3.12 ± 0.23 mm and 3.19 ± 0.24 mm when measured with the Galilei G4 and the Pentacam HR, respectively. The mean white-to-white distance measured was 11.84 ± 0.31 mm and 11.90 ± 0.43 mm when measured with the Galilei G4 and the Pentacam HR, respectively. Mean pupil diameters were measured as 3.22 ± 0.58 mm and 3.22 ± 0.52 mm when measured with the Galilei G4 and the Pentacam HR, respectively. Finally, the mean anterior chamber angle was 34.30 ± 2.86 degrees when it was measured with the Galilei G4, and 39.26 ± 2.85 degrees when measured with the Pentacam HR. A comparative analysis revealed that the Galilei G4 yielded a significantly lower (P0.05 for both devices were obtained for the white-to-white distance measurements. Conclusion: The Galilei G4 and Pentacam HR Scheimpflug systems cannot be used interchangeably because they produce significant measurement differences.

  15. Ethnic difference of the anterior chamber area and volume and its association with angle width.

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    Wang, Dandan; Qi, Meng; He, Mingguang; Wu, Lingling; Lin, Shan

    2012-05-31

    To compare the anterior chamber area/volume (ACA/ACV) and their relationship with the drainage angle between adult Caucasians and Chinese. Study groups were comprised of four age- and sex-matched cohorts: American Caucasians, American Chinese, southern mainland Chinese, and northern mainland Chinese. All subjects were consecutively recruited from general ophthalmology clinics except for southern mainland Chinese participants who were drawn from an ongoing population-based study. Anterior segment optical coherence tomography (ASOCT) images were obtained under dark conditions. Customized software was used to analyze structural indices including ACA/ACV, angle opening distance (AOD), anterior chamber depth (ACD), anterior chamber width (ACW), lens vault (LV), corneal arc depth (CAD), iris thickness (IT), iris curvature (ICurv), and iris area (IArea). Data from 121, 124, 121, and 120 participants were obtained of American Caucasians, American Chinese, and southern and northern mainland Chinese, respectively. After multiple linear regression analysis, adjusting for age, sex, pupil diameter (PD), and axial length (AL), ACA/ACV was positively associated with ACD, ACW, CAD, and corneal radius of curvature (CR) but negatively related with ICurv and IArea. Ethnic Chinese had significantly smaller ACA (β = -0.18, P = 0.022) and ACV (β = -3.9, P = 0.001) than Caucasians. ACV contributes the most to AOD variation for both Chinese (standardized regression coefficient [SRC] = 0.47, P ACV independent of ACD, ACW, ICurv, IArea, PD, CR, and AL. ACA/ACV is the most prominent contributor to angle width variation for both Chinese and Caucasians in this study.

  16. Comparison of Scheimpflug imaging and spectral domain anterior segment optical coherence tomography for detection of narrow anterior chamber angles.

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    Grewal, D S; Brar, G S; Jain, R; Grewal, S P S

    2011-05-01

    To compare the performance of anterior chamber volume (ACV) and anterior chamber depth (ACD) obtained using Scheimpflug imaging with angle opening distance (AOD500) and trabecular-iris space area (TISA500) obtained using spectral domain anterior segment optical coherence tomography (SD-ASOCT) in detecting narrow angles classified using gonioscopy. In this prospective, cross-sectional observational study, 265 eyes of 265 consecutive patients underwent sequential Scheimpflug imaging, SD-ASOCT imaging, and gonioscopy. Correlations between gonioscopy grading, ACV, ACD, AOD500, and TISA500 were evaluated. Area under receiver operating characteristic curve (AUC), sensitivity, specificity, and likelihood ratios (LRs) were calculated to assess the performance of ACV, ACD, AOD500, and TISA500 in detecting narrow angles (defined as Shaffer grade ≤1 in all quadrants). SD-ASOCT images were obtained at the nasal and temporal quadrants only. Twenty-eight eyes (10.6%) were classified as narrow angles on gonioscopy. ACV correlated with gonioscopy grading (PACV correlated with TISA500 for nasal (r=0.135, P=0.029) and temporal (P=0.160, P=0.009) quadrants and also with AOD500 for nasal (r=0.498, PACV (AUC=0.935; 95% confidence interval (CI) =0.898-0.961) performed similar to ACD (AUC=0.88, P=0.06) and significantly better than AOD500 nasal (AUC=0.761, P=0.001), AOD500 temporal (AUC=0.808, PACV had 90% sensitivity and 88% specificity for detecting narrow angles. Positive and negative LRs for ACV were 8.63 (95% CI=7.4-10.0) and 0.11 (95% CI=0.03-0.4), respectively. ACV measurements using Scheimpflug imaging outperformed AOD500 and TISA500 using SD-ASOCT for detecting narrow angles.

  17. Ring melanoma of the anterior chamber angle as a mimicker of pigmentary glaucoma.

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    Stadigh, Anni; Puska, Päivi; Vesti, Eija; Ristimäki, Ari; Turunen, Joni A; Kivelä, Tero T

    A 19-year-old man noticed blurred vision in his right eye. He had an intraocular pressure of 60 versus 12 mmHg in the fellow eye. He was initially diagnosed with an atypical, advanced pigmentary glaucoma. The intraocular pressure did not respond to maximal medication, deep sclerectomy, goniopuncture, and 2 cyclophotocoagulations. Sixteen months after presentation, malignancy was first suspected, and the eye was enucleated. A ring melanoma of the anterior chamber angle was confirmed by the histopathologic examination. Normal nuclear staining for breast cancer 1 gene (BRCA1)-associated protein 1 suggested that the tumor was likely of disomy 3 type with a favorable prognosis. No local or systemic recurrence has developed within 4 years. A literature review of this rare type of minimal volume diffuse uveal melanoma identified 18 additional patients. The initial diagnosis in 18 of the 19 patients with a ring melanoma of the anterior chamber angle was unilateral glaucoma with a median intraocular pressure of 40 mmHg and an age range of 16-76 years. Liver metastasis developed in 5 of 12 patients older than 45 years. This rare subtype is estimated to account for 0.05%-0.16% of all uveal melanomas. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Association of biometric factors with anterior chamber angle widening and intraocular pressure reduction after uneventful phacoemulsification for cataract.

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    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.

  19. Repeatability, reproducibility, agreement characteristics of 2 SD-OCT devices for anterior chamber angle measurements.

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    Akil, Handan; Dastiridou, Anna; Marion, Kenneth; Francis, Brian; Chopra, Vikas

    2017-04-01

    To evaluate the agreement, reproducibility, and repeatability of 2 spectral domain optical coherence tomography (SD-OCT) devices in Schwalbe's line (SL)-based anterior chamber angle parameters. The inferior anterior chamber angle of 65 eyes from 65 participants (33 right eyes and 32 left eyes) were scanned twice with the Nidek RS 3000 Advanced SD-OCT and Cirrus SD-OCT. SL angle opening distance (SL-AOD) and SL trabecular-iris-space area (SL-TISA) were graded by masked certified graders at the Doheny Image Reading Center. The mean SL-AOD/SL-TISA was 617.3 ± 237.9 µm/0.211 ± 0.086 mm 2 for the Cirrus and 633.7 ± 219.3 µm/0.218 ± 0.080 mm 2 for the Nidek RS 3000 Advanced SD-OCT. The repeatability (intraclass correlation coefficients [ICCs] >0.936) and intergrader reproducibility (ICCs >0.915) in SL-AOD and SL-TISA with Cirrus OCT were excellent. The repeatability (ICCs >0.948) and intergrader reproducibility (ICCs >0.709) in SL-AOD and SL-TISA with the Nidek RS 3000 Advanced SD-OCT were moderate to good. Moderate agreement between the 2 devices was also documented with a mean difference of -15.3 (limits of agreement [LoA] -246.5 to 277.1) mm for SL-AOD and 0.006 (LoA -0.096 to 0.108) mm in SL-TISA. Both devices were able to provide consistent angle measurements, but repeatability and reproducibility were better in Cirrus SD-OCT than in Nidek RS 3000 Advanced SD-OCT. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  20. Evaluation of the change of anterior chamber parameters before and after laser peripheral iridectomy in primary angle-closure suspetive with Pentacam anterior segment analysis system

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    Chi Du

    2015-05-01

    Full Text Available AIM:To investigate the sensitive parameters of the anterior chamber changes with Pentacam anterior segment analysis system before and after laser peripheral iridectomy(LPIin primary angle-closure suspetive(PACS.METHODS: Sixty eyes of 33 PACS patients were enrolled in this study. Pentacam examination was performed before and 1d after LPI to measure the central anterior chamber depth(CACD, the peripheral anterior chamber depth(PACD, the anterior chamber volume(ACVand the peripheral anterior chamber angle(ACA. Statistical analysis used paired t test. RESULTS: There was no statistical significance on the changes of ACD. PACD and ACV increased significantly between before and 1d after LPI. ACA was widened from(22.26°±5.18°to(26.42°±5.20°, which were increased significantly between before and 1d after LPI.CONCLUSION: LPI can deepen the PACD and increase the ACV in PACS. PACD and ACV are the sensitive parameters of the anterior chamber changes with Pentacam anterior segment analysis system.

  1. Anterior chamber paracentesis and pH values in patients with acute primary angle closure.

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    Lu, Da-Wen; Tai, Ming-Cheng; Chang, Yun-Hsiang; Liang, Chang-Min; Chen, Ching-Long; Chien, Ke-Hung; Chen, Jiann-Torng; Chen, Yi-Hao

    2013-04-01

    To assess the efficacy and safety of anterior chamber paracentesis (ACP) and the changes in pH values in eyes with acute primary angle closure (APAC). This retrospective case-control study involved 22 patients with APAC who underwent ACP (study group) and 21 patients with APAC who did not undergo ACP (control group). Intraocular pressure (IOP) and visual acuity were measured before treatment and 15 min and 24 h after treatment in both groups. The pH of aqueous humor was measured immediately after ACP in the study group. A total of 43 eyes in 43 patients were reviewed. The IOP 15 min after ACP (23.3 ± 9.6 mmHg) and 24 h after ACP (21.6 ± 12.0 mmHg) were significantly lower than that before ACP (58.6 ± 12.9 mmHg). The IOP 15 min after ACP was significantly lower than the IOP 15 min after conventional treatment (55.4 ± 10.3 mmHg). Visual acuity recovery was achieved earlier after ACP than after conventional treatment. Hyphema after ACP was noted in one eye. The mean pH of the aqueous humor in APAC was 6.99 ± 0.35. The pH of the aqueous humor significantly correlated with the duration of acute IOP elevation and the IOP before ACP. ACP is an effective and safe procedure. The pH of aqueous humor is lower in eyes with APAC of longer duration and in eyes with higher IOP at presentation.

  2. Ultrasound biomicroscopy dark room provocative testing: a quantitative method for estimating anterior chamber angle width.

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    Ishikawa, H; Esaki, K; Liebmann, J M; Uji, Y; Ritch, R

    1999-01-01

    To describe a quantitative method for measuring the iridocorneal angle recess area, and, using this, to evaluate factors associated with appositional angle-closure during dark room provocative testing using ultrasound biomicroscopy (UBM). All patients (178 patients, 178 eyes) with clinically narrow angles referred for UBM dark room provocative testing between September 1996 and March 1998 were enrolled in this study. Images of the inferior quadrant of the angle taken under standardized dark and light conditions were analyzed. The angle recess area (ARA) was defined as the triangular area demarcated by the anterior iris surface, corneal endothelium, and a line perpendicular to the corneal endothelium drawn from a point 750 microm anterior to the scleral spur to the iris surface. ARA, and acceleration and gamma-intercept of the linear regression analysis of the ARA were calculated. In the linear regression formula, y = ax + b, the acceleration a describes the rate at which the angle widens from the scleral spur; the y-intercept b describes the distance from the scleral spur to the iris. Under dark conditions, the angles in 99 patients (55.6%) showed evidence of appositional angle-closure during testing. ARA (0.11 +/- 0.04 vs. 0.15 +/- 0.05 mm2, P dark conditions (P = .1, paired t-test), while acceleration a did (P dark conditions (P < .0001). CONCLUSIONS The ARA linear regression formula provides useful quantitative information about angle recess anatomy. The more posterior the iris insertion on the ciliary face, the less likely the provocative test will be positive.

  3. Differences in Baseline Dark and the Dark-to-Light Changes in Anterior Chamber Angle Parameters in Whites and Ethnic Chinese

    OpenAIRE

    Wang, Dandan; Chiu, Cynthia; He, Mingguang; Wu, Lingling; Kao, Andrew; Lin, Shan

    2011-01-01

    When measured by anterior segment optical coherence tomography, the anterior chamber angle in the Chinese tends to be narrower in the dark, but the dark-to-light change is greater than in whites, independent of refractive status and anterior segment ocular dimensions.

  4. ABCC5, a gene that influences the anterior chamber depth, is associated with primary angle closure glaucoma.

    Directory of Open Access Journals (Sweden)

    Monisha E Nongpiur

    2014-03-01

    Full Text Available Anterior chamber depth (ACD is a key anatomical risk factor for primary angle closure glaucoma (PACG. We conducted a genome-wide association study (GWAS on ACD to discover novel genes for PACG on a total of 5,308 population-based individuals of Asian descent. Genome-wide significant association was observed at a sequence variant within ABCC5 (rs1401999; per-allele effect size =  -0.045 mm, P = 8.17 × 10(-9. This locus was associated with an increase in risk of PACG in a separate case-control study of 4,276 PACG cases and 18,801 controls (per-allele OR = 1.13 [95% CI: 1.06-1.22], P = 0.00046. The association was strengthened when a sub-group of controls with open angles were included in the analysis (per-allele OR = 1.30, P = 7.45 × 10(-9; 3,458 cases vs. 3,831 controls. Our findings suggest that the increase in PACG risk could in part be mediated by genetic sequence variants influencing anterior chamber dimensions.

  5. Flat Anterior Chamber after Trabeculectomy in Secondary Angle-Closure Glaucoma with BEST1 Gene Mutation: Case Series.

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    Yimin Zhong

    Full Text Available Trabeculectomy has been regarded as a mainstay of initial treatment in eyes of angle closure glaucoma (ACG with peripheral anterior synechia > 180° in the Chinese population while its efficacy in secondary ACG with BEST1 gene mutation remains unclear. We set out to investigate the treatment outcome of trabeculectomy for secondary ACG in a group of patients with autosomal recessive bestrophinopathy (ARB.In this retrospective case series study, 8 secondary ACG patients with ARB and their 4 recruited family members underwent a thorough ophthalmic examination including best-corrected visual acuity, Goldmann applanation tonometry, gonioscopy, and fundus examinations. Ultrasound biomicroscopy, optical coherence tomography (OCT, ultrasound A-scan, B-scan, electro-oculography (EOG, Humphrey perimetry, fundus photography, fundus fluorescein angiography (FFA and indocyanine green angiography (ICGA were also performed. Blood samples were obtained in the patients and their available family members to analyze the variants of the BEST1 gene. Trabeculectomy was performed in the 8 patients (15 eyes.The age of onset varied from 13 to 38 years. The average axial length (AL of the affected eyes was 21.82 ± 0.92 mm and the average anterior chamber depth (ACD was 2.19 ± 0.29 mm. There was marked axial shallowing of the anterior chamber in all 15 eyes after trabeculectomy, and was not improved with potent mydriatics. The IOP was elevated in 3 eyes. Variable degree of yellowish subretinal deposits was observed in the posterior retina. The FFA showed punctuate or patched hyperfluorescence suggesting retinal pigment epithelium impairment. The ICGA demonstrated dilatation of choroidal vessels. The OCT revealed diffused neuroretinal detachment in the posterior and midperipheral retina, with intraretinal fluid collections, and hyperreflective subretinal accumulations. The average subfoveal choroidal thickness of the patients was 382.36 ± 80.09 μm. All the patients and

  6. Anterior Chamber Angle Shape Analysis and Classification of Glaucoma in SS-OCT Images

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    Soe Ni Ni

    2014-01-01

    Full Text Available Optical coherence tomography is a high resolution, rapid, and noninvasive diagnostic tool for angle closure glaucoma. In this paper, we present a new strategy for the classification of the angle closure glaucoma using morphological shape analysis of the iridocorneal angle. The angle structure configuration is quantified by the following six features: (1 mean of the continuous measurement of the angle opening distance; (2 area of the trapezoidal profile of the iridocorneal angle centered at Schwalbe's line; (3 mean of the iris curvature from the extracted iris image; (4 complex shape descriptor, fractal dimension, to quantify the complexity, or changes of iridocorneal angle; (5 ellipticity moment shape descriptor; and (6 triangularity moment shape descriptor. Then, the fuzzy k nearest neighbor (fkNN classifier is utilized for classification of angle closure glaucoma. Two hundred and sixty-four swept source optical coherence tomography (SS-OCT images from 148 patients were analyzed in this study. From the experimental results, the fkNN reveals the best classification accuracy (99.11±0.76% and AUC (0.98±0.012 with the combination of fractal dimension and biometric parameters. It showed that the proposed approach has promising potential to become a computer aided diagnostic tool for angle closure glaucoma (ACG disease.

  7. Differences in baseline dark and the dark-to-light changes in anterior chamber angle parameters in whites and ethnic Chinese.

    Science.gov (United States)

    Wang, Dandan; Chiu, Cynthia; He, Mingguang; Wu, Lingling; Kao, Andrew; Lin, Shan

    2011-12-09

    To assess the anterior chamber drainage angle width in the dark and the dark-to-light change (Δ) between Caucasians and Chinese aged 40 years and older. The study groups comprised four age- and sex-matched cohorts: American Caucasians, American Chinese, southern mainland Chinese, and northern mainland Chinese. Anterior segment optical coherence tomography (ASOCT) images of the anterior chamber angles were obtained under both light and dark conditions. The parameters analyzed included angle opening distance (AOD), angle recess area (ARA), and trabecular-iris space area (TISA). Data were obtained from 121, 124, 121, and 120 participants who were American Caucasians, American Chinese, and southern and northern mainland Chinese, respectively. In a multiple linear regression analysis, adjusted for age, sex, refractive status, pupil size, lens location, and anterior chamber depth (ACD) and width (ACW), the ethnic Chinese had significantly smaller ARAs (regression coefficient, β = -0.06, P dark-to-light change analysis, the independent associations between angle width and iris thickness (IT) and iris curvature (ICurv) were identified only in the Chinese. Compared with the Caucasians, the ethnic Chinese had smaller ARA and TISA, but greater dark-to-light changes in AOD and TISA, independent of refractive status and overall ocular anterior segment dimensions.

  8. Width of anterior chamber angle determined by OCT, and correlation to refraction and age in a German working population: the MIPH Eye&Health Study.

    Science.gov (United States)

    Vossmerbaeumer, Urs; Schuster, Alexander K; Fischer, Joachim E

    2013-12-01

    Optical coherence tomography (OCT) of the anterior segment allows quantitative analysis of the geometry of the chamber angle. We performed bilateral spectral-domain OCT measurements in healthy, emmetropic, hyperopic, and myopic subjects to establish correlations between the width of the angle, the refraction, and intraocular pressure of the test persons. Out of 4,617 eyes (2,309 subjects), those with refractive errors of  +3 diopters were identified by objective refraction measurement (KR-8800 Kerato-Refractometer, Topcon Inc., Japan) and examined using the anterior segment mode of a spectral-domain 3D OCT-2000 (Topcon Inc., Japan). Non-contact tonometry was performed (CT-80, Topcon Inc., Japan). One hundred and eight eyes of 54 emmetropic subjects (± 0.5 dpt) served as reference group. Previous ocular surgery was exclusion criterion in all groups. Width of the chamber angle was determined using semi-automated software tools and statistical analysis of the data (Pearson correlation, ANOVA with post-hoc test and Bonferroni correction, regression analysis) was performed using SPSS software (SPSS 19.0, Chicago, IL, USA). Six hundred and sixty-eight eyes of 398 persons (292 male, 96 female) were included in the study. Mean hyperopic refraction was +4.24 (+3  to +7.75) dpt, mean myopic refraction was -5.86 (-4 to -11.75) dpt. Valid chamber angle OCT measurements could be obtained from 50 (69.4 %) hyperopic and 400 (71.4 %) myopic eyes meeting the inclusion criteria. The mean width of the chamber angle was determined as 31.8° (range: 13.5 to 45.6, SD 7.49) in the hyperopic group, 40.8° (range: 19.3 to 66.0, SD 8.1) in the myopic group, and 36.3° (range: 21.1 to 51.8, SD 6.8) in the emmetropic reference group. Correlation was highly significant (p > 0.001) between refractive error and the aperture of the chamber angle as measured from OCT. The association of the intraocular pressure and the refraction was also highly significant (p > 0.001) for the three groups

  9. Gnathostomiasis of the anterior chamber

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    Barua P

    2007-01-01

    Full Text Available Ocular involvement with Gnathostoma spinigerum occurs years after the initial infection that is acquired by ingestion of poorly cooked, pickled seafood or water contaminated with third stage larvae. Here we report a case of gnathostomiasis of the left eye of a 32-year-old lady hailing from Meghalaya, India. Her vision had deteriorated to hand movement. Slit lamp examination revealed a live, actively motile worm in the anterior chamber, which was extracted by supra temporal limbal incision and visual acuity was restored.

  10. Anterior chamber volume. Its measurement and clinical application.

    Science.gov (United States)

    Coakes, R L; Lloyd-Jones, D; Hitchings, R A

    1979-04-01

    Measurement of anterior chamber volume is discussed and attention drawn to a new, convenient slit-image method, which was used to study anterior chamber depth and volume before and after prophylactic peripheral iridectomy in the fellow eyes of patients presenting with unilateral acute angle-closure glaucoma. There was no significant change in depth after iridectomy but the mean anterior chamber volume increased significantly (P less than 0.01), by nearly 3 per cent. This increase was due to elimination of peripheral iris bombé which was not present in two control groups of normal eyes, one matched for anterior chamber depth and the other for age and refraction. Peripheral iris bombé may be a quantifiable factor predisposing to the development of acute angle-closure glaucoma.

  11. Anterior segment optical coherence tomography of acute primary angle closure.

    Science.gov (United States)

    Zhang, Hai Tao; Xu, Liang; Cao, Wei Fang; Wang, Ya Xing; Jonas, Jost B

    2010-06-01

    To assess anterior segment optical coherence tomographic measurements of patients after acute unilateral primary angle closure (APAC) compared with those of normal subjects. The clinical observational study included 41 hospital-based patients after unilateral APAC, their unaffected contralateral eyes, and 205 subjects. These were selected from the population-based Beijing Eye Study, and were matched with the APAC group for age, gender, and refractive error. All study participants underwent slit-lamp adapted optical coherence tomography (OCT). Compared with the unaffected contralateral eyes, eyes with APAC had a significantly shallower anterior chamber (P APAC and the unaffected contralateral eyes both showed more shallow anterior chambers (P APAC group, the anterior chamber angle was closed in three or more quadrants. Anterior segment OCT measurements show significant differences between eyes with APAC, contralateral eyes at risk for APAC, and normal eyes. This may open possibilities for a semi-automatic assessment of subjects at risk for APAC by anterior segment OCT. The anterior chamber angle was closed most often in the nasal quadrant, and, in APAC, the angle was closed in three or more quadrants.

  12. RETAINED STONE PIECE IN ANTERIOR CHAMBER

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    ZvornicaninJasmin, Nadarevic-VodencarevicAmra

    2015-04-01

    Full Text Available ABSTRACT We read with interest the article by Surekha et al. regarding the retained stone piece in anterior chamber. Similar to the results of previous studies, the authors found that delayed intraocular foreign body (IOFB management can result in good visual outcome without an apparent increased risk of endophthalmitis or other deleterious side effects. However, the authors failed to explain the exact reason for the diminution of vision in patients left eye. It is unclear what the uncorrected visual acuity was and what kind of correction was used, more precisely type and amount of cylinder, given the presence of the corneal opacity. Since the size of the IOFB is approximately 4x4x1mm, significant irido-corneal angle changes resulting in intraocular pressure raise and optic nerve head damage can be expected. Traumatic glaucoma following open globe injury can occur in 2.7 to 19% of cases, with several risk factors associated with glaucoma development (advanced age, poor visual acuity at presentation,perforating rather than penetrating ocular injury,lens injury, presence of vitreous hemorrhage and presence of an IOFB. Earlier reportsof latetraumaticoptic neuropathy onset, even after several years, indicate that this possibility cannot be completely ruled out too. Therefore, repeated intraocular pressure measurements, gonioscopy, pupillary reaction assessment, together with through posterior segment examination including visual field and optical coherence tomography examinations can be useful in determining the possible optic nerve damage as one of the possible reasons for visual acuity reduction. The authors did not suggest any operative treatment at this time. However, it should bear in mind that the inert anterior chamber IOFB could be a risk factor for non-infectious endophthalmitis development even after many years. Also, long term retained anterior chamber foreign body leads to permanent endothelial cell loss and can even result in a corneal

  13. Anterior chamber collapse syndrome in a koala.

    Science.gov (United States)

    Liddle, Vl; Naranjo, C; Bernays, Me

    2014-05-01

    Anterior chamber collapse syndrome has been recognised in various species and is associated with early-life ocular disease or trauma. It is important to differentiate this acquired condition from a congenital malformation. An adult female koala (Phascolarctos cinereus) was referred for assessment of buphthalmos and severe keratitis of the right eye. The degree of keratitis obstructed examination of intraocular structures. Enucleation of the affected eye was performed and the histopathological diagnosis was anterior chamber collapse syndrome and secondary glaucoma. This case contributes to the limited information available in the literature on anterior chamber collapse syndrome, a disease unique in having secondary glaucoma with minimal or no inflammation. The case also expands the literature available on ocular disease in koalas. More specifically, this is the only reported case of glaucoma, of any aetiology, in the koala. © 2014 Australian Veterinary Association.

  14. Evaluation of the Effects of Menstrual Cycle on Anterior Chamber Parameters as Measured with Pentacam

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    Arzu Seyhan Karatepe

    2013-01-01

    Full Text Available Pur po se: To evaluate the effects of endogenous gonadotropic hormones (follicle-stimulating hormone, luteinizing hormone and sex steroids (progesterone, estrogen to anterior segment parameters. Ma te ri al and Met hod: Thirty healthy females who had a menstrual cycle of 28±1 day and with a mean age of 36.5±7.56 (range, 20 – 46 years were included in the study. Starting from the first day of their cycle, Pentacam Scheimpflug camera measurements were performed on the 1st, 3rd, 7th, 12th, 16th, 21st, 26th, and 28th days. The central corneal thickness, anterior chamber depth, anterior segment volume, keratometric values, anterior chamber angle value, and pupilla diameter of both eyes were evaluated. Repeated measures analysis of variance test was used for statistical analysis. Re sults: No difference that reaches statistical significance was found in the means of central corneal thickness, anterior chamber volume, keratometric values, anterior chamber angle, and pupilla diameter between the days. Mean anterior chamber depth measurement of the right eyes on the 1st day was 2.72±0.44 mm, whereas it was 2.77±0.46 mm on the 26th day. Mean anterior chamber depth measurement of the left eyes on the 1st day was 2.74±0.42 mm, whereas it was 2.80±0.43 mm on the 26th day. This increment of anterior chamber depth value from the 1st to the 26th days was found to be statistically significant (p≤0.05. Dis cus si on: Progesterone and estrogen that rise in the second half of the menstrual cycle might have a deepening effect on the anterior chamber. These findings should be further investigated with more profound studies that also evaluate the hormonal values and their correlations with anterior segment parameters. (Turk J Ophthalmol 2013; 43: 15-8

  15. Comparison of Anterior Segment-Optical Coherence Tomography Parameters in Phacomorphic Angle Closure and Acute Angle Closure Eyes.

    Science.gov (United States)

    Moghimi, Sasan; Ramezani, Farshid; He, Mingguang; Coleman, Anne L; Lin, Shan C

    2015-12-01

    The purpose of this study is to compare anterior segment-optical coherence tomography (AS-OCT) parameters in phacomorphic angle closure and acute primary angle closure (APAC) eyes. In this cross-sectional case series, a total of 134 patients with phacomorphic angle closure (28 eyes) or APAC (54 eyes), as well as normal control subjects (52 eyes), were enrolled. Patients underwent AS-OCT imaging and A-scan biometry of both eyes. Anterior chamber depth (ACD), anterior chamber area (ACA), iris thickness (IT), iris curvature, lens vault (LV), anterior vault (AV), and angle parameters including angle opening distance (AOD 500 and AOD750) and trabecular iris space area (TISA500 and TISA750) were measured in qualified images using the Zhongshan Angle Assessment Program and compared among eyes with phacomorphic angle closure, APAC, and normal control subjects. Phacomorphic angle closure and APAC eyes had smaller AOD, ACD, ACA, ACW, AV, and posterior corneal arc length and greater LV than normal controls (P APAC eyes: ACD 1042 μm (OR,12.12; P APAC eyes. In multivariate analysis, ACD, LV, AOD500, and axial length could significantly distinguish the two entities. Ocular biometric parameters can differentiate phacomorphic angle closure from APAC eyes. Shallower ACD and greater LV, axial length, and ACA are the main parameters that distinguish phacomorphic angle closure from APAC.

  16. A simple photogrammetric method of measuring anterior chamber volume.

    Science.gov (United States)

    Johnson, S B; Coakes, R L; Brubaker, R F

    1978-04-01

    We devised a convenient method of measuring anterior chamber volume in man. Photographs of the anterior chamber were taken with a Zeiss photographic slit lamp with a Polaroid attachment, and measured with a specially constructed transparent scale. Using this method, the standard deviation of individual measurements of volume on different occasions in a given eye was 8 microliter. The standard deviation of the differences between right and left eyes of normal subjects was 10 microliter. The volume of the anterior chamber measured in 78 eyes of 39 normal subjects (mean age, 28 years; range, 19 to 56 years) was found to be 209 +/- 37 microliter (mean +/- SD). We observed a small negative correlation between the age of the subject and the volume of the anterior chamber.

  17. Analysis of influence factors on anterior chamber volume by corneal horizontal diameter and anterior chamber depth

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    Ming-Hua Zhang

    2013-08-01

    Full Text Available AIM: To investigate the correlative factors of corneal horizontal diameter(CHDand anterior chamber depth(ACDand discuss the affecting factors of anterior chamber volume(ACV.METHODS: A total of 241 cases(482 eyesof myopia aged 6-47 years were collected on randomly. There were 124(248 eyesmale subjects and 117(234 eyesfemale subjects. CHD and ACD were measured with the Orbscan ⅡZ system, and each measurement was repeated three times. SPSS 17.0 software was used to analyze the correlation data. Mathematical model was set up to research anterior chamber volume. RESULTS: The average of CHD is(11.69±0.51mm, with diameter of(11.74±0.49mm in male and(11.64±0.53mm in female.The average of ACD was(3.04±0.30mm, with depth of(3.07±0.30mm in male and(3.02±0.29in female. Differences in gender of CHD and ACD were significant in the t-test for independent samples(t= -2.265, -1.971; P=0.024, 0.05, these size of male were both larger than that of female. Through person correlation analysis, a negative correlation was found between CHD and age, ACD and age(r= -0.260,-0.246; P=0, 0; a positive correlation was found between CHD and ACD(r=0.297; P=0, the regression equation between CHD and ACD in myopia population was Y=1.025+0.173X(F=46.440,P=0, R2=0.088, where Y represents ACD and X represents CHD. CONCLUSION: There are statistically significant difference between male and female in CHD, ACD and ACV. The size of these in male is larger than in female. The CHD is positively correlated with the ACD, and CHD, ACD and ACV are negatively correlated with age and are not associated with the degree of myopia.

  18. Anterior Segment Dimensions Following Laser Iridotomy in Acute Primary Angle Closure and Fellow Eyes.

    Science.gov (United States)

    Moghimi, Sasan; Bijani, Faezeh; Chen, Rebecca; Yasseri, Mehdi; He, Mingguang; Lin, Shan C; Weinreb, Robert N

    2018-02-01

    To compare the change in anterior segment morphology after laser peripheral iridotomy (LPI) in acute primary angle closure (APAC) and their fellow eyes. Prospective, fellow eye-matched case series. In this study 42 individuals with unilateral episode of APAC were enrolled and the anterior segment optical coherence tomography (ASOCT) images were obtained in both eyes at baseline and at 6 weeks after LPI. A linear mixed-effects model was used to compare changes in anterior chamber and angle variables with consideration of laterality as the random effect and pupil diameter as the fixed effect. APAC eyes had smaller angle parameters (P = .013 for all), less central anterior chamber depth (cACD) (P APAC and fellow eyes. cACD (P = .003) and ACA (P APAC eyes. However, there was no significant change in cACD (P = .190) and LV (P = .430) in fellow eyes. In both APAC eyes and fellow eyes, iris curvature decreased after LPI (P APAC eyes and their fellow eyes, LPI resulted in significant anterior chamber angle widening and increased anterior chamber area. In APAC eyes, the iris flattened, cACD deepened, and the lens shifted posteriorly after resolution of the attack. However, in fellow eyes, the increase in ACA was mainly owing to decreased iris curvature. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Changes of anterior and posterior corneal curvature and anterior chamber depth after SMILE

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    Li Li

    2017-12-01

    Full Text Available AIM: To observe the changes of anterior and posterior corneal curvature and anterior chamber depth after small incision lenticule extraction(SMILEfor low and high myopic astigmatism. METHODS: Sixty-three cases(88 eyesundergone SMILE in our hospital were included. The patients were divided into two groups based on astigmatism degree: the Group A: -2.00D to -4.00D astigmatism, the Group B: -0.25D to -1.00D astigmatism. Patients were examined at 1wk, 1 and 3mo after operations. Visual acuity, intraocular pressure, refraction, corneal curvature and anterior chamber depth were recorded. The change of anterior and posterior corneal curvature and anterior chamber depth was compared. Spearman correlation analysis and independent t test were used for statistical analysis. RESULTS: Surgery was done well in all patients without complications. No statistically significant difference was found between the two groups in posterior corneal curvature and anterior chamber depth preoperatively, postoperatively 7d,1 and 3mo(P>0.05. One week postoperatively, the anterior corneal curvature was statistically significant from that of preoperative in both groups(PP>0.05. CONCLUSION: No significant change of anterior and posterior corneal curvature and anterior chamber depth was found after SMILE for correcting low and high myopic astigmatism. One week after SMILE the anterior corneal curvature become stable.

  20. Measurement of early changes in anterior chamber morphology after cataract extraction measured by anterior segment optical coherence tomography.

    Science.gov (United States)

    Kasai, Kozue; Takahashi, Genichiro; Kumegawa, Koichi; Dogru, Murat

    2015-10-01

    To evaluate the serial changes in anterior chamber depth (ACD) and angle parameters early after cataract surgery using anterior segment optical coherence tomography (ASOCT). This was a retrospective chart review, case-control study; 150 eyes of 106 patients who underwent cataract surgery. Based on ACD and angle findings, the eyes were classified into two groups, open-angle eyes (87 eyes) and narrow-angle eyes (63 eyes). ASOCT was used to measure ACD and angle parameters (angle opening distance, angle recess area, trabecular iris space area, and trabecular iris angle (TIA [1]). Serial changes in each group were measured before and 1 day, 1 week, and 1 month after cataract surgery, and the differences between the two groups were compared. ACD and all angle parameters in both groups at each examination time after cataract surgery were significantly different from the preoperative values (p < 0.01). In addition, all angle parameters significantly differed between the two groups at each examination time after cataract surgery (p < 0.001). However, ACD after surgery was not significantly different, irrespective of ACD before surgery. ACD and TIA500 both showed significantly greater changes from before surgery to 1 day after surgery in narrow-angle eyes compared to open-angle eyes (p < 0.001). Cataract surgery increases ACD and all angle parameters early after the surgery. However, the degree of angle widening in narrow-angle eyes was not as much as that in open-angle eyes, suggesting that factors other than the lens influence the angle closure.

  1. Clearance from the anterior chamber of RBCs from human diabetics

    International Nuclear Information System (INIS)

    Williams, G.A.; Hatchell, D.L.; Collier, B.D.; Knobel, J.

    1984-01-01

    Erythrocytes from diabetic patients manifest decreased deformability and increased adherence. These abnormal membrane properties may diminish the ability of erythrocytes (RBCs) from diabetics to undergo deformation in passage through the trabecular meshwork. Using sodium chromate Cr 51-labeled RBCs from type I diabetic patients with proliferative retinopathy and normal control subjects, we studied RBC clearance from the rabbit anterior chamber. The mean time for 50% clearance (T50) of RBCs from diabetics (76 hours) was significantly longer than that for RBCs from normal subjects (19.5 hours). In this model, RBCs from diabetics have a slower clearance from the anterior chamber than do RBCs from normal subjects

  2. Study of biological measurement parameters of anterior segment in primary acute angle-closure glaucoma

    Directory of Open Access Journals (Sweden)

    Jun-Jie Bian

    2015-02-01

    Full Text Available AIM:To investigate biological measurement parameters of anterior segment in acute angle-closure glaucoma(AACG.METHODS: Forty-six eyes of 46 patients with AACG and 52 eyes of 52 patients with shallow anterior chamber and 50 eyes of 50 normal individuals were examined. The parameters of anterior segment including chamber crowd rate(CCR, lens thickness(LT, lens position(LPand anterior chamber depth(ACDwere measured by A-ultrasound according to different ages in each group. The data were performed statistical analysis in three groups.RESULTS: In each age range group(≥50~59 years old, ≥60~69 years old, ≥70 years old, statistically significant differences in three groups(AACG, shallow anterior chamber group and the controlswere found in CCR, LT, LP, ACD(PPP>0.05between AACG and shallow anterior chamber group in each age range group.CONCLUSION: CCR can be used as the index of evaluating crowding state of anterior segment in AACG patients and the sensitivity is better than LT and LP.

  3. [Radiographic anatomy of pulp chamber of Chinese permanent anterior teeth].

    Science.gov (United States)

    Jia, Liu-He; Huang, Ming-Ding; Gao, Xiao-Jie; Luo, Shi-Gao; Luo, Hong-Xia; Tan, Hong; Zhou, Xue-Dong

    2006-06-01

    The aim of this study was to measure and analyze the anatomic characteristics of the pulp chamber of Chinese permanent anterior teeth radiographically. There were 137 human permanent anterior teeth to be used. The crown length, crown width and crown thickness were measured by vernier caliper. Labial-lingual and mesial-distal radiographs were obtained by parallel technique and Photoshop 8.0 was adopted for measuring the largest labial-lingual length, the largest mesial-distal length, the pulp chamber height and the distance between the lingual surface of the crown and the corresponding wall of the pulp chamber; the ratios of the largest labial-lingual length to the crown thickness, the largest mesial-distal length to the crown width and the pulp chamber height to the crown length were calculated. Finally the coefficients of variance were caculated. (1) The ratios of the largest mesial-distal length to the crown width of maxillary and mandibular canines were statistically different from those of the other anterior teeth. There was not statistically significant difference for those ratios either between maxillary and mandibular canines or among incisors. (2) Indexes of the pulp chamber had higher variance than those of the external morphology. (3) The distance between the lingual surface of the crown and the corresponding wall of the pulp chamber had the smallest coefficient of variance. (4) The largest mesial-distal length of the pulp chamber had the largest coefficient of variance, except for the mandibular canines. This study provided anatomical basis for clinical work; the distance between the lingual surface of the crown and the corresponding wall of the pulp chamber could be used as a depth reference for the endodontic access, and the access should not be extended excessively in mesial-distal direction.

  4. Predictive factors for anterior chamber fibrin formation after vitreoretinal surgery

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    Leonardo Provetti Cunha

    2014-04-01

    Full Text Available Purpose: The aim of this study was to investigate possible predictive factors related to anterior chamber fibrin formation after vitreoretinal surgery in a large series of patients. Methods: The data of 185 eyes of 185 patients submitted to vitreoretinal surgery was reviewed. The following variables were evaluated: the postoperatively presence of fibrin, age, diabetes mellitus, the vitrectomy system gauge (20, 23 or 25 gauge, the type of vitreous substitute, the influence of prior surgical procedures and the combination with cataract extraction. To evaluate predictive factors for anterior chamber fibrin formation, univariate analysis was performed. A multivariate stepwise logistic regression model was adjusted to investigate factors associated with fibrin formation (p<0.05. Results: Fibrinoid anterior chamber reaction was found in 12 (6.4% patients. For multivariate logistic regression analysis, balanced salt solution (BSS, the chance of fibrin occurrence was 5 times greater (odds ratio 4.83, CI 95% 1.302 - 17.892; p=0.019, while combination with phacoemulsification increased the chance of fibrin formation by 20 times (odds ratio 20, CI 95% 2.480 - 161.347; p=0.005. No significant difference was found regarding other variables. Conclusion: Anterior chamber fibrin formation is an unwanted complication after vitreoretinal surgery. Factors such as combined performance of phacoemulsification and the use of balanced salt solution as a vitreous substitute may predispose the occurrence of this complication.

  5. Anterior chamber gas bubbles in open globe injury.

    Science.gov (United States)

    Barnard, E B G; Baxter, D; Blanch, R

    2013-01-01

    We present a case of a 40-year-old soldier who was in close proximity to the detonation of an improvised explosive device (IED). Bubbles of gas were visible within the anterior chamber of his left eye. The authors propose that intraocular gas, present acutely after trauma, is diagnostic of open globe injury and is of particular importance in remote military environments.

  6. Microbiological profile of anterior chamber aspirates following uncomplicated cataract surgery

    Directory of Open Access Journals (Sweden)

    Prajna N

    1998-01-01

    Full Text Available Anterior chamber aspirate cultures were done for 66 patients who underwent either an uncomplicated intracapsular cataract extraction, extracapsular cataract extraction with posterior-chamber intraocular lens implantation, or phacoemulsification with posterior-chamber intraocular lens implantation. The aspirate was obtained at the time of wound closure. The aspirates were immediately transferred to the microbiology laboratory where one drop of the aspirate was placed on a glass slide for gram stain, and the remainder was unequally divided and inoculated into blood agar, chocolate agar and thioglycolate broth. The cultures were incubated at 37° C with 5% CO2 and held for 5 days. Of 66 patients 4 (6%, had smear-positive anterior chamber aspirates. None of the aspirates showed any growth on any of the 3 culture media used. None of the eyes in the study developed endophthalmitis. This study concludes that there is no contamination of the anterior chamber by viable bacteria after cataract surgery, irrespective of the mode of intervention.

  7. Pretreatment anterior segment imaging during acute primary angle closure: insights into angle closure mechanisms in the acute phase.

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    Sng, Chelvin C A; Aquino, Maria Cecilia D; Liao, Jiemin; Ang, Marcus; Zheng, Ce; Loon, Seng Chee; Chew, Paul T K

    2014-01-01

    To describe anterior segment optical coherence tomography (ASOCT) parameters during acute primary angle closure (APAC) before therapeutic interventions and comparative analyses of biometric parameters of APAC eyes with fellow eyes. Prospective, comparative case series. Thirty-one consecutive patients with APAC. All patients underwent ASOCT imaging of both eyes during the attack, before therapeutic interventions were administered. Custom software was used to measure anterior chamber depth (ACD), anterior chamber area (ACA), anterior chamber volume (ACV), iris curvature (I-Curv), iris area (I-Area), lens vault (LV), and angle opening distance (AOD750), trabecular iris space area (TISA750), and iris thickness (IT750) at 750 μm from the scleral spur. Multivariate logistic regression modeling using forward selection was used to determine the most important biometric variables associated with APAC compared with the fellow eye during the attack. Anterior segment biometric parameters associated with APAC. The mean age of the patients was 60.9±7.5 years, and 11 patients (35.5%) were male. The mean intraocular pressure was 3.8±9.2 mmHg in the APAC eye and 4.2±4.3 mmHg in the fellow eye before treatment (P APAC eyes had smaller ACD, ACA, ACV, I-Curv (all P APAC occurrence, with ACD accounting for 18.1% and I-Curv accounting for 14.1% of this variance. Shallower ACD and smaller I-Curv were the 2 main anterior segment biometric parameters associated with APAC during the attack. These findings present new insights into the anterior segment biometric parameters of APAC and fellow eyes before therapeutic interventions. Anatomic changes in the anterior segment explained only about one third of the variance in APAC occurrence, and the role of nonanatomic factors require further investigation. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  8. [Diagnostic value of Blumensaat angle for anterior cruciate ligament injury].

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    Cheng, Xiang-Yun; Feng, Jiang-Feng; Lu, Yan-Hui; Zhao, Yong-Liang; Yang, Zi-Quan

    2017-08-25

    The receiver operator characteristic(ROC) curve was used to determine the best Blumensaat angle for the diagnosis of anterior cruciate ligament injury, so as to objectively evaluate the diagnostic value of Blumensaat angle for anterior cruciate ligament injury. Total 167 patients who had knee arthroscopic treatment in a hospital from January 2015 to January 2016 were retrospectively studied, and the patients' age, gender, left and right limb condition were recorded. The patients were divided into two groups according to Blumensaat angle measured on the MRI: group A(Blumensaat angle0°). The ROC curve was drawn from the statistical data of the group B to get the best critical value of the anterior cruciate ligament injury when the Blumensaat angle was more than 0°. According to the best critical value obtained by ROC curve, the coincidence rate of the total sample was obtained. There were no significant differences in patients' age, gender, and affected limbs. There were 51 patients in group A, in which 49 patients were diagnosed as anterior cruciate injury under arthroscopy(gold standard for diagnosis of anterior cruciate ligament injury), and 2 patients were diagnosed as no anterior cruciate injury under arthroscopy. When the Blumensaat angle was=15°, the probability of anterior cruciate ligament injury was greater. When the Blumensaat angle was 0° to 15°, the anterior cruciate ligament was more likely to be not injured. The Blumensaat angle=15° were used to diagnose the injury of anterior cruciate ligament. Compared with the results of arthroscopy, the coincidence rate of the total sample was 92.8%. Blumensaat angle is helpful to diagnose the ACL injuries. When the Blumensaat angle was =15°, the probability of ACL injury is greater.

  9. Anterior segment optical coherence tomography parameters in subtypes of primary angle closure.

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    Guzman, Celeste P; Gong, Tianxia; Nongpiur, Monisha E; Perera, Shamira A; How, Alicia C; Lee, Hwee Kuan; Cheng, Li; He, Mingguang; Baskaran, Mani; Aung, Tin

    2013-08-07

    To compare anterior segment parameters, assessed by anterior segment optical coherence tomography (ASOCT), in subjects categorized as primary angle closure suspect (PACS), primary angle closure (PAC), primary angle closure glaucoma (PACG), and previous acute PAC (APAC); and to identify factors associated with APAC. This was a prospective ASOCT study of 425 subjects with angle closure (176 PACS, 66 PAC, 125 PACG, and 58 APAC). Customized software was used to measure ASOCT parameters, including angle opening distance (AOD750), trabecular-iris space area (TISA750), anterior chamber depth, width, area and volume (ACD, ACW, ACA, ACV), iris thickness (IT750), iris area (IAREA), and lens vault (LV). Mean differences in anterior segment parameters were evaluated by analysis of covariance (ANCOVA) adjusted for age, sex, and pupil diameter (PD). Comparison among the different subgroups showed that ACD, ACA, and ACV were smallest, and IT750 thickest in the APAC group compared with the other subgroups (P APAC group (1218 ± 34 μm) followed by PAC (860 ± 31 μm), PACG (845 ± 23 μm), and PACS (804 ± 19 μm), respectively (P = APAC group had the narrowest angles, the PACS group had the widest (P APAC. Eyes with APAC had the narrowest angles, smallest anterior segment dimensions, thickest iris, and largest LV compared with PACS, PAC, and PACG. LV, TISA750, and IT750 were the major determinants of APAC.

  10. Anterior segment changes after pharmacologic mydriasis using Pentacam and optical coherence tomography in angle closure suspects

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    Jing-Min Guo

    2015-10-01

    Full Text Available AIM:To compare the dynamic changes of anterior segment parameters especially iris morphology induced by pharmacologic mydriasis between angle closure suspects and normal controls.METHODS:The study group comprised 19 eyes of 19 angle closure suspects and 19 eyes of 19 age- and sex-matched normal open-angle eyes. Pentacam and optical coherence tomography measurements before and 30min after instillation of compound tropicamide eye drop were performed and compared. Biometric evaluations of iris tomography and anterior chamber angle were estimated by a customized image-processing software.RESULTS:Baseline axial length, iris cross sectional area and volume did not differ significantly between angle closure suspects and normal controls. Angle closure suspects had smaller pupil size, narrower anterior segment dimension and axial length, thinner iris with greater curve in comparison with normal controls. Pharmacologic mydriasis led to significant increments in iris thickness at 750 μm, anterior chamber depth and volume, whereas significant decrements in iris curve, cross sectional area and volume in both groups. Angle opening distance at 500 μm was increased significantly in normal controls (from 0.465±0.115 mm to 0.539±0.167 mm, P=0.009, but not in angle closure suspects (from 0.125±0.100 mm to 0.145±0.131 mm, P=0.326. Iris volume change per millimeter of pupil dilation (△IV/△PD decreased significantly less in angle closure suspects than normal controls (-2.47±1.33 mm2 vs -3.63±1.58 mm2, P=0.019. Linear regression analysis showed that the change of angle opening distance at 500 μm was associated most with the change of central anterior chamber depth (β=0.841, P=0.002 and △IV/△PD (β=0.028, P=0.002, followed by gender (β=0.062, P=0.032.CONCLUSION:Smaller iris volume decrement per millimeter of pupil dilation is related significantly with the less anterior angle opening in angle closure suspects after pharmacologic mydriasis. Dynamic

  11. Linguatula serrata in the anterior chamber of the eye

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    Muna Bhende

    2014-01-01

    Full Text Available We report a case of intraocular Linguatula in healthy young female who presented with a history of trivial trauma, dislocated lens, inflammation and secondary glaucoma. A mobile worm was seen in the anterior chamber. Pars plana lensectomy and vitrectomy was planned to remove both the cataractous lens and the parasite during which the worm disappeared from view but was later recovered from the cassette fluid. It was identified as the nymphal form of Linguatula serrata (tongue worm.

  12. Recurrent iridocyclitis due to cotton fiber in anterior chamber.

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    Joshi, Rajesh S

    2016-01-01

    Cotton is commonly used during ophthalmic surgical procedure. Cotton fibers may get attracted to the instruments due to electrostatic forces and become adhered to the surface. With the introduction of these instruments during the surgical procedure cotton fiber may get entry into the eye. In the literature they have been infrequently reported due to insignificant effect on the ocular structures. We present a case of recurrent iridocyclitis due to cotton fiber in the anterior chamber. Patient was relived of his symptoms after removal. A 78-year-old male presented with pain, redness and blurring of right eye vision since last six months. The patient had undergone phacoemulsification with implantation of hydrophilic intraocular lens (IOL) six years earlier. Postoperative follow up was uneventful from his records till last 6 months. Slit-lamp examination revealed a cotton fiber in the anterior chamber touching the endothelium. Keratic precipitates were seen on the endothelium. Removal of the cotton fiber resulted in subsidence of inflammation. We recommend use of plastic eye and trolley drapes, lint free instrument wipes and use of needle cap to support the globe during creation of side port while performing phacoemulsification instead of cotton buds to avoid entry of cotton fiber into the anterior chamber. © NEPjOPH.

  13. Late spontaneous resolution of a double anterior chamber post deep anterior lamellar keratoplasty

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    Andrea Passani

    2017-01-01

    Full Text Available A 31-year-old healthy male underwent deep anterior lamellar keratoplasty with big-bubble technique for treatment of keratoconus in his right eye. One week after surgery, he presented with detachment of the endothelium-Descemet complex with formation of a double anterior chamber, despite the apparent absence of an intraoperative Descemet membrane rupture. A subsequent intervention with the intent to relocate the corneal graft button was not effective, because the detachment appeared again one day later. The authors hypothesized that, at the time of the stromal dissection with big bubble technique, a small amount of air penetrated into the anterior chamber, creating a false pathway through the trabecular meshwork. The aqueous humor then penetrated the graft flowing through the false pathway, causing the endothelium-Descemet detachment. The persistence of that pathway, even after the intervention of graft repositioning, caused the failure of the latter procedure and persistence of the double chamber. We decided to wait and observe. The double anterior chamber spontaneously resolved in approximately three months.

  14. Reproducibility of Scleral Spur Identification and Angle Measurements Using Fourier Domain Anterior Segment Optical Coherence Tomography

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    Ricardo J. Cumba

    2012-01-01

    Full Text Available Purpose. To evaluate intraobserver and interobserver agreement in locating the scleral spur landmark (SSL and anterior chamber angle measurements obtained using Fourier Domain Anterior Segment Optical Coherence Tomography (ASOCT images. Methods. Two independent, masked observers (SR and AZC identified SSLs on ASOCT images from 31 eyes with open and nonopen angles. A third independent reader, NPB, adjudicated SSL placement if identifications differed by more than 80 μm. Nine months later, SR reidentified SSLs. Intraobserver and interobserver agreement in SSL placement, trabecular-iris space area (TISA750, and angle opening distance (AOD750 were calculated. Results. In 84% of quadrants, SR’s SSL placements during 2 sessions were within 80 μm in both the X- and Y-axes, and in 77% of quadrants, SR and AZC were within 80 μm in both axes. In adjudicated images, 90% of all quadrants were within 80 μm, 88% in nonopen-angle eyes, and 92% in open-angle eyes. The intraobserver and interobserver correlation coefficients (with and without adjudication were above 0.9 for TISA750 and AOD750 for all quadrants. Conclusions. Reproducible identification of the SSL from images obtained with FD-ASOCT is possible. The ability to identify the SSL allows reproducible measurement of the anterior chamber angle using TISA750 and AOD750.

  15. Dynamic changes in optic disc morphology, choroidal thickness, anterior chamber parameters, and intraocular pressure during Valsalva maneuver

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    Alper Mete

    Full Text Available ABSTRACT Purpose: To investigate the effects of the Valsalva maneuver (VM on optic disc morphology, choroidal thickness, and anterior chamber parameters. Methods: This prospective observational study included 60 eyes of 60 healthy subjects. The anterior chamber parameters, including central corneal thickness (CCT, anterior chamber depth (ACD, anterior chamber angle (ACA, anterior chamber volume (ACV, pupil diameter (PD, axial length (AL, subfoveal and peripapillary choroidal thickness, optic disc parameters, and intraocular pressure (IOP, were measured at rest and during VM. Results: VM did not have any significant influence on AL, subfoveal and peripapillary choroidal thickness, optic disc area, rim area, cup area, cup-to-disc area ratio, vertical cup-to-disc ratio, rim volume, cup volume, and nerve head volume measurements (for all; p >0.05. IOP and PD significantly increased during VM (for both; p <0.001. VM significantly decreased CCT, ACD, ACA, and ACV values (for all; p <0.001. Moreover, the optic nerve cup volume decreased and the horizontal cup-to-disc ratio significantly increased during VM (for both; p <0.05. Conclusions: VM may cause transient changes in IOP, optic disc morphology, and anterior chamber parameters.

  16. Maintenance of the anterior chamber during penetrating keratoplasty.

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    Kramer, S G; Stewart, H L

    1976-01-01

    A description of the author's (S.G.K.) technique for penetrating keratoplasty is provided. The salient features include corneal removal, storage, and corneal graft cutting procedures of Kaufman and his co-workers. In addition, a specially designed suturing contact lens is described which allows maintenance of the anterior chamber during penetrating keratoplasty. It is suggested that trauma to the all-important cornea endothelium can be minimized by application of this technique, because it significantly reduces the likelihood of endothelial trauma induced by mechanical contact of the endothelium with intraocular recipient structures during suturing.

  17. Relationship between intraocular pressure and angle configuration: an anterior segment OCT study.

    Science.gov (United States)

    Chong, Rachel S; Sakata, Lisandro M; Narayanaswamy, Arun K; Ho, Sue-Wei; He, Mingguang; Baskaran, Mani; Wong, Tien Yin; Perera, Shamira A; Aung, Tin

    2013-03-05

    To assess the relationship between intraocular pressure (IOP) and anterior chamber angle (ACA) configuration as assessed by gonioscopy and anterior segment optical coherence tomography (AS-OCT). A total of 2045 subjects aged 50 years and older, were recruited from a community clinic and underwent AS-OCT, Goldmann applanation tonometry, and gonioscopy. A quadrant was classified as closed on gonioscopy if the posterior trabecular meshwork could not be seen. A closed quadrant on AS-OCT was defined by the presence of any contact between the iris and angle wall anterior to the scleral spur. Customized software (Zhongshan Angle Assessment Program, Guangzhou, China) was used to measure AS-OCT parameters on AS-OCT scans, including anterior chamber depth, area, and volume; iris thickness (IT) and curvature; lens vault; angle opening distance; and trabecular-iris space area. IOP values were adjusted for age, sex, diabetes and hypertension status, body mass index, central corneal thickness, and presence of peripheral anterior synechiae. Mean age of study subjects was 63.2 ± 8.0 years, 52.6% were female, and 89.4% were Chinese. Mean IOP was 14.8 ± 2.4 mm Hg (range 826). IOP (mean ± SE) increased with number of quadrants with gonioscopic angle closure (none: 14.6 ± 0.2; one: 14.7 ± 0.3; two: 15.0 ± 0.3; three: 15.0 ± 0.3; four: 15.6 ± 0.3 mm Hg; P measured on AS-OCT images, except for IT and lens vault. There was an association between the extent of angle closure, as assessed on AS-OCT and gonioscopy, with increasing IOP.

  18. Correlation between intraocular pressure and the biometric structure of the anterior chamber in patients of chronic renal failure with hemodialysis

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    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.

  19. Influence of anterior chamber depth, anterior chamber volume, axial length, and lens density on postoperative endothelial cell loss.

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    Reuschel, Anna; Bogatsch, Holger; Oertel, Nicole; Wiedemann, Renate

    2015-05-01

    To evaluate the influence of anterior chamber depth (ACD), anterior chamber volume (ACV), lens density (LD), and axial length (AL) as risk factors on endothelial cell loss 3 months after cataract surgery. We enrolled 47 patients with senile cataract who were operated between July 2012 and March 2013 by the same surgeon using torsional phacoemulsification. Preoperatively, we measured ACD, ACV, and LD using the Oculus Pentacam®. The AL was determined using the IOL Master®. Primary outcomes were central endothelial density (ECD) and corrected distance visual acuity (CDVA) 3 months after surgery We evaluated the effect of ACD, ACV, LD, and AL as possible risk factors of postoperative percentage endothelial cell loss (ECL). The median age was 72 years. The median CDVA before surgery was 0.5 improving to 1.0 postoperatively. The median ECL was 5.2 % (range 1.7 %-7.6 %). These results are comparable to our previous study (median ECL 6.9 % after 3 months) [Reuschel et al. (2010) J Cataract Refract Surg]. The median ACD in our study was 2.56 mm (range 2.26 mm-2.8 mm). Median ACV was 144 mm(3) (range 121 mm(3)-158 mm(3)]. The median LD was 12.4 (range 11.4-13.7). Median AL was 23.1 mm (range 22.7 mm-23.9 mm). Our correlation analysis showed no significant correlation between ACD, ACV, LD, AL, and postoperative ECL. ACD, ACV, AL, and LD were not identified as risk factors of postoperative endothelial cell loss in our analysis.

  20. Anterior ischemic optic neuropathy precipitated by acute primary angle closure

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    Choudhari Nikhil

    2010-01-01

    Full Text Available A 59-year-old man with a history of longstanding systemic hypotension developed asymmetric non-arteritic anterior ischemic optic neuropathy (NAION apparently precipitated by bilateral sequential acute primary angle closure. NAION is very rarely reported in association with raised intraocular pressure. In contrast to optical coherence tomography, the failure of scanning laser polarimetry to detect axonal swelling was another interesting finding. Possible reasoning for these observations is discussed.

  1. Comparison of anterior segment parameters between the acute primary angle closure eye and the fellow eye.

    Science.gov (United States)

    Lee, Jong Rak; Sung, Kyung Rim; Han, Seungbong

    2014-05-20

    To investigate features of the anterior segment (AS) of the affected eye compared to the fellow eye within the same patient in acute primary angle closure (APAC). Thirty-six patients with unilateral APAC were imaged with AS optical coherence tomography (OCT) before medical or laser treatment for the acute attack. Anterior chamber depth (ACD), iris curvature (IC), iris thickness at 750 μm from the scleral spur (IT750), lens vault (LV), anterior chamber area (ACA), and iris area were estimated by using ImageJ software (version 1.46). Conditional logistic regression analysis was performed to find the associated factors with the prediction of APAC. When compared to fellow eyes, affected eyes showed significantly shallower ACD (1.90 ± 0.24 and 1.55 ± 0.30 mm, respectively; P APAC. Greater LV was the most prominent feature of affected eyes compared to fellow eyes in APAC patients when assessed by AS OCT. This may play a role in the development of acute attack in primary angle closure. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  2. Effects of hemodialysis on corneal and anterior chamber morphometry and intraocular pressure in patients with end-stage renal disease

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    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.

  3. Steeper Iris Conicity Is Related to a Shallower Anterior Chamber: The Gutenberg Health Study

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    Pfeiffer, Norbert; Nickels, Stefan; Schulz, Andreas; Wild, Philipp S.; Blettner, Maria; Lackner, Karl; Beutel, Manfred E.; Münzel, Thomas; Vossmerbaeumer, Urs

    2017-01-01

    Purpose To report the distribution of iris conicity (steepness of the iris cone), investigate associated factors, and test whether pseudophakia allows the iris to sink back. Methods A population-based cross-sectional study was carried out. Ophthalmological examination including objective refraction, biometry, noncontact tonometry, and Scheimpflug imaging (Pentacam®, Oculus) was performed including automated measurement of iris conicity. 3708 phakic subjects, 144 subjects with bilateral and 39 subjects with unilateral pseudophakia were included. Multivariable analyses were carried out to determine independently associated systemic and ocular factors for iris conicity in phakic eyes. Results Mean iris conicity was 8.28° ± 3.29° (right eyes). Statistical analysis revealed associations between steeper iris conicity and shallower anterior chamber depth, thicker human lens and higher corneal power in multivariable analysis, while older age was related to a flatter iris conicity. Refraction, axial length, central corneal thickness, pupil diameter, and intraocular pressure were not associated with iris conicity. Pseudophakia resulted in a 5.82° flatter iris conicity than in the fellow phakic eyes. Conclusions Associations indicate a correlation between iris conicity with risk factors for angle-closure, namely, shallower anterior chamber depth and thicker human lens. In pseudophakic eyes, iris conicity is significantly lower, indicating that cataract surgery flattens the iris. PMID:29085672

  4. Steeper Iris Conicity Is Related to a Shallower Anterior Chamber: The Gutenberg Health Study

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    Alexander K. Schuster

    2017-01-01

    Full Text Available Purpose. To report the distribution of iris conicity (steepness of the iris cone, investigate associated factors, and test whether pseudophakia allows the iris to sink back. Methods. A population-based cross-sectional study was carried out. Ophthalmological examination including objective refraction, biometry, noncontact tonometry, and Scheimpflug imaging (Pentacam®, Oculus was performed including automated measurement of iris conicity. 3708 phakic subjects, 144 subjects with bilateral and 39 subjects with unilateral pseudophakia were included. Multivariable analyses were carried out to determine independently associated systemic and ocular factors for iris conicity in phakic eyes. Results. Mean iris conicity was 8.28° ± 3.29° (right eyes. Statistical analysis revealed associations between steeper iris conicity and shallower anterior chamber depth, thicker human lens and higher corneal power in multivariable analysis, while older age was related to a flatter iris conicity. Refraction, axial length, central corneal thickness, pupil diameter, and intraocular pressure were not associated with iris conicity. Pseudophakia resulted in a 5.82° flatter iris conicity than in the fellow phakic eyes. Conclusions. Associations indicate a correlation between iris conicity with risk factors for angle-closure, namely, shallower anterior chamber depth and thicker human lens. In pseudophakic eyes, iris conicity is significantly lower, indicating that cataract surgery flattens the iris.

  5. Segmentation and Quantification for Angle-Closure Glaucoma Assessment in Anterior Segment OCT.

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    Fu, Huazhu; Xu, Yanwu; Lin, Stephen; Zhang, Xiaoqin; Wong, Damon Wing Kee; Liu, Jiang; Frangi, Alejandro F; Baskaran, Mani; Aung, Tin

    2017-09-01

    Angle-closure glaucoma is a major cause of irreversible visual impairment and can be identified by measuring the anterior chamber angle (ACA) of the eye. The ACA can be viewed clearly through anterior segment optical coherence tomography (AS-OCT), but the imaging characteristics and the shapes and locations of major ocular structures can vary significantly among different AS-OCT modalities, thus complicating image analysis. To address this problem, we propose a data-driven approach for automatic AS-OCT structure segmentation, measurement, and screening. Our technique first estimates initial markers in the eye through label transfer from a hand-labeled exemplar data set, whose images are collected over different patients and AS-OCT modalities. These initial markers are then refined by using a graph-based smoothing method that is guided by AS-OCT structural information. These markers facilitate segmentation of major clinical structures, which are used to recover standard clinical parameters. These parameters can be used not only to support clinicians in making anatomical assessments, but also to serve as features for detecting anterior angle closure in automatic glaucoma screening algorithms. Experiments on Visante AS-OCT and Cirrus high-definition-OCT data sets demonstrate the effectiveness of our approach.

  6. Is being female a risk factor for shallow anterior chamber? The associations between anterior chamber depth and age, sex, and body height

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    Wei-Cherng Hsu

    2014-01-01

    Full Text Available Aim of Study: To analyze the association between anterior chamber depth (ACD and age, sex, and body height (BH. Materials and Methods: One thousand four hundred eighty eyes of 1480 adults 40 years of age and older receiving preoperative evaluation for cataract surgery were recruited consecutively from June 1, 2006, to December 31, 2010. ACD was measured with the Zeiss IOLMaster. Univariate and multivariate linear regression models were used to analyze the correlations, and receiving operator characteristic (ROC curves and the area under the curve (AUC were used for evaluating the predictability of an ACD less than 2.70 mm. Results: ACD was negatively correlated with age and positively correlated with BH in both univariate and multivariate regression analysis (P < 0.001. Sex was associated with ACD in univariate analysis, but not after adjustment with age and BH. In predicting an ACD less than 2.70 mm, the AUCs of ROC curves for ′age and sex′, ′age and BH′, and ′age, sex, and BH′ were 0.687, 0.689, and 0.689, respectively. Conclusion: Age and BH were independent associating factors of ACD; however, sex was not. Older people and shorter ones likely had shallower ACD, and therefore were predisposed to Primary angle closure glaucoma (PACG. The predictability of ACD by age and BH solely was low, and adding sex did not increase it.

  7. Repeatability and reproducibility of anterior chamber volume measurements using 3-dimensional corneal and anterior segment optical coherence tomography.

    Science.gov (United States)

    Fukuda, Shinichi; Kawana, Keisuke; Yasuno, Yoshiaki; Oshika, Tetsuro

    2011-03-01

    To evaluate the repeatability and reproducibility of anterior chamber volume (ACV) measurements using swept-source 3-dimensional corneal and anterior segment optical coherence tomography (CAS-OCT) and dual Scheimpflug imaging. Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan. Nonrandomized clinical trial. Measurements were taken in normal eyes (subject group) and in eyes with primary angle closure (PAC) (patient group). In the subject group, the entire ACV and the central 8.0 mm diameter ACV were measured using CAS-OCT and dual Scheimpflug imaging. In the patient group, the entire ACV and 8.0 mm ACV were measured using CAS-OCT. The coefficient of variation and intraclass correlation coefficient (ICC) were calculated to evaluate repeatability and reproducibility, and the correlation between the 2 devices was assessed. In the subject group, the mean 8.0 mm ACV was 110.14 mm(3) ± 12.57 (SD) using CAS-OCT and 114.51 ± 14.69 mm(3) using Scheimpflug imaging; there was a significant linear correlation (r = 0.878, P ACV on CAS-OCT was 165.15 ± 29.29 mm(3). The ICCs of the 8.0 mm and entire ACV measurements were greater than 0.94. The coefficients of repeatability and reproducibility of the 8.0 mm ACV and entire ACV measurements were less than 5%. In the patient group, the 8.0 mm and entire ACV measurements showed good reproducibility and repeatability. The CAS-OCT method allowed noninvasive measurement of the entire ACV with sufficient repeatability and reproducibility. The 8.0 mm ACV measurements with CAS-OCT and Scheimpflug imaging were comparable. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  8. Clinical outcomes of Ahmed glaucoma valve in anterior chamber versus ciliary sulcus.

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    Bayer, A; Önol, M

    2017-04-01

    PurposeTo evaluate the outcomes of Ahmed glaucoma valve (AGV) tube insertion through the anterior chamber angle (ACA) or through the ciliary sulcus (CS).Patients and methodsIn this case-control study, we retrospectively reviewed the charts of consecutive glaucoma patients who had undergone AGV implantation either through the ACA or the CS between March 2009 and December 2014. The main outcome measures were intraocular pressure (IOP), number of glaucoma medications prescribed, best corrected visual acuity (BCVA), glaucoma type, success rate, complications, and survival ratios. Statistical analysis was carried out using SPSS.ResultsThere were 68 eyes in the ACA group and 35 eyes in the CS group. There were no significant differences between the groups for age, sex, laterality, IOP, preoperative glaucoma medication number, BCVA or glaucoma type (P>0.05). The postoperative follow-up period was 27.2±16.5 months and 30.2±17.7 months for the ACA and the CS groups (P=0.28); IOP values were significantly reduced at the last visit to 16.4±7.2 mm Hg and 14.4±6.8 mm Hg. The difference in the last-visit IOP between the groups was not significant (P=0.06), but the IOP reduction ratio was higher in the CS group (P=0.03). There was no significant difference in the number of postoperative medications (P=0.18). Postoperative complications were similar, but the incidence of flat anterior chamber was higher in the ACA group (P=0.05).ConclusionsThe use of an AGV can control IOP in the majority of cases whether placed in the ACA or the CS. The IOP reduction ratio seemed to be higher in the CS group.

  9. Angle Class I malocclusion with anterior negative overjet

    Directory of Open Access Journals (Sweden)

    Paulo Ávila de Souza

    2016-04-01

    Full Text Available ABSTRACT This clinical case report describes the orthodontic treatment of an 8-year and 9-month old female patient with Angle Class I malocclusion, anterior crossbite and canine Class III relationship. Orthodontic treatment was carried out in two stages. The first one was orthopedic, while the second one included the use of a fixed appliance and the need for space gain for reshaping of maxillary lateral incisors. The two-stage treatment combined with multidisciplinary Restorative Cosmetic Dentistry allowed excellent esthetic and functional outcomes to be achieved. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO as a requirement for the title of certified by the BBO.

  10. Estimation of axial curvature of anterior sclera: correlation between axial length and anterior scleral curvature as affected by angle kappa.

    Science.gov (United States)

    Lee, Sang-Mok; Choi, Hyuk Jin; Choi, Heejin; Kim, Mee Kum; Wee, Won Ryang

    2016-10-07

    BACKGROUND: Though the development and fitting of scleral contact lenses are expanding steadily, there is no simple method to provide scleral metrics for scleral contact lens fitting yet. The aim of this study was to establish formulae for estimation of the axial radius of curvature (ARC) of the anterior sclera using ocular biometric parameters that can be easily obtained with conventional devices. A semi-automated stitching method and a computational analysis tool for calculating ARC were developed by using the ImageJ and MATLAB software. The ARC of all the ocular surface points were analyzed from the composite horizontal cross-sectional images of the right eyes of 24 volunteers; these measurements were obtained using anterior segment optical coherence tomography for a previous study (AS-OCT; Visante). Ocular biometric parameters were obtained from the same volunteers with slit-scanning topography and partial coherence interferometry. Correlation analysis was performed between the ARC at 8 mm to the axis line (ARC[8]) and other ocular parameters (including age). With ARC obtained on several nasal and temporal points (7.0, 7.5, 8.0, 8.5, and 9.0 mm from the axis line), univariate and multivariate linear regression analyses were performed to develop a model for estimating ARC with the help of ocular biometric parameters. Axial length, spherical equivalent, and angle kappa showed correlations with temporal ARC[8] (tARC[8]; Pearson's r = 0.653, -0.579, and -0.341; P = 0.001, 0.015, and 0.015, respectively). White-to-white corneal diameter (WTW) and anterior chamber depth (ACD) showed correlation with nasal ARC[8] (nARC[8]; Pearson's r = -0.492 and -0.461; P = 0.015 and 0.023, respectively). The formulae for estimating scleral curvatures (tARC, nARC, and average ARC) were developed as a function of axial length, ACD, WTW, and distance from the axis line, with good determinant power (72 - 80 %; SPSS ver. 22.0). Angle kappa showed strong

  11. Measurement of and Factors Associated with the Anterior Chamber Volume in Healthy Chinese Adults

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    Yuan Zong

    2017-01-01

    Full Text Available Purpose. To measure the anterior chamber volume (ACV and determine factors associated with the ACV in healthy Chinese adults. Methods. In this cross-sectional study, we used swept-source optical coherence tomography (SS-OCT to measure ACV and other anterior segment parameters. Factors associated with ACV were also determined. Results. A total of 313 healthy Chinese adults were enrolled. The anterior segment parameters, including ACV, could be measured by SS-OCT with excellent repeatability and reproducibility. There was a significant difference between the horizontal and vertical anterior chamber widths (ACW (P<0.05, with a mean difference of 390 μm. The ACV (mean 153.83±32.42 mm3 was correlated with most of the anterior segment parameters, especially anterior chamber depth (ACD, which accounted for about 85% of the variation of ACV. Most of the anterior segment parameters were significantly correlated with age, and the relative changes in ACV and ACD were greatest in subjects aged 41–50 years. Conclusion. ACV was correlated with most of the anterior segment parameters measured in this study, particularly ACD. The relatively large difference between horizontal and vertical ACW suggests that the ACV could and should be measured using multiple OCT scans.

  12. Retrospective Study of Vitreous Tap Technique Using Needle Aspiration for Management of Shallow Anterior Chamber during Phacoemulsification

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    Ashraf Ahmed Nossair

    2017-01-01

    Full Text Available Purpose. To evaluate the technique of vitreous tap using needle aspiration for management of anterior chamber shallowness during phacoemulsification. Methods. A retrospective study included 26 eyes of 17 patients who underwent phacoemulsification in which vitreous tap was performed using a 27-gauge needle attached to a 5 ml syringe, inserted 3.5 mm from the limbus to aspirate 0.2 ml of liquefied vitreous if a cohesive (OVD failed to sufficiently deepen the anterior chamber. Results. Preoperative anterior chamber depth was 2.31 ± 0.26 mm, axial length was 21.7 ± 0.67 mm, lens thickness was 4.5 ± .19 mm, and cataract grade was 3.77 ± 1.4. Preoperative CDVA in LogMAR units was 0.98 ± 0.75. Coexisting angle closure glaucoma was present in 7 patients (26.92% preoperatively. Vitreous needle tap was successful in vitreous removal on the first attempt in 26 eyes (100%. Postoperative follow-up period was 22.88 ± 10.24 (4–39 months. The final postoperative CDVA in LogMAR units was 0.07 ± 0.1, while the final postoperative IOP was 16.54 ± 1.45 mmHg. No complications related to vitreous tap were noted. Conclusion. Vitreous needle tap is a simple, cost-effective, and safe technique for management of shallow anterior chamber in phacoemulsification.

  13. Single session, intrauser repeatability of anterior chamber biometric and corneal pachy-volumetric parameters using a new Scheimpflug+Placido device.

    Science.gov (United States)

    Prakash, Gaurav; Srivastava, Dhruv

    2016-01-01

    To analyze single session, intrauser reliability of a Scheimpflug device for anterior chamber (AC) and corneal parameters. In this observational study, 100 normal candidates underwent Scheimpflug analysis with Sirius 3D Rotating Scheimpflug Camera and Topography System (Costruzione Strumenti Oftalmici, Italy). Two scans in dark room conditions were performed by the same experienced user. The candidates were asked to keep both eyes closed for 5min before the scans. Exclusion criteria were previous ocular surgery, corneal scarring and anterior segment/posterior segment anomalies. Only the right eyes were used for the analysis. Both corneal (central, minimum, and apical thickness, volume, horizontal visible iris diameter, and apical curvature) and anterior chamber (volume, depth, angle, horizontal diameter) measurements were evaluated. There was no difference in the means of repeated measurements (p>0.05, ANOVA). Intraclass correlations between the measures were high and ranged from 0.995-0.997 for corneal to 0.964-0.997 for anterior chamber (AC) parameters. The precision of repeatability measures (1.96×Sw) was approximately 5μ for the central and minimum corneal thickness, 8μ for the apical corneal thickness, 0.06mm for AC (anterior chamber) depth and less than 2° for the AC angle. Sirius Scheimpflug system has high repeatability for both corneal and AC parameters in normal eyes. Copyright © 2015 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  14. A Novel Method of Quantitative Anterior Chamber Depth Estimation Using Temporal Perpendicular Digital Photography.

    Science.gov (United States)

    Zamir, Ehud; Kong, George Y X; Kowalski, Tanya; Coote, Michael; Ang, Ghee Soon

    2016-07-01

    We hypothesize that: (1) Anterior chamber depth (ACD) is correlated with the relative anteroposterior position of the pupillary image, as viewed from the temporal side. (2) Such a correlation may be used as a simple quantitative tool for estimation of ACD. Two hundred sixty-six phakic eyes had lateral digital photographs taken from the temporal side, perpendicular to the visual axis, and underwent optical biometry (Nidek AL scanner). The relative anteroposterior position of the pupillary image was expressed using the ratio between: (1) lateral photographic temporal limbus to pupil distance ("E") and (2) lateral photographic temporal limbus to cornea distance ("Z"). In the first chronological half of patients (Correlation Series), E:Z ratio (EZR) was correlated with optical biometric ACD. The correlation equation was then used to predict ACD in the second half of patients (Prediction Series) and compared to their biometric ACD for agreement analysis. A strong linear correlation was found between EZR and ACD, R = -0.91, R 2 = 0.81. Bland-Altman analysis showed good agreement between predicted ACD using this method and the optical biometric ACD. The mean error was -0.013 mm (range -0.377 to 0.336 mm), standard deviation 0.166 mm. The 95% limits of agreement were ±0.33 mm. Lateral digital photography and EZR calculation is a novel method to quantitatively estimate ACD, requiring minimal equipment and training. EZ ratio may be employed in screening for angle closure glaucoma. It may also be helpful in outpatient medical clinic settings, where doctors need to judge the safety of topical or systemic pupil-dilating medications versus their risk of triggering acute angle closure glaucoma. Similarly, non ophthalmologists may use it to estimate the likelihood of acute angle closure glaucoma in emergency presentations.

  15. Lenticonus diagnosis in Alport's syndrome: Anterior capsule apical angle calculation using Scheimpflug imagery.

    Science.gov (United States)

    Jarrín, E; Jarrín, I; Arnalich-Montiel, F

    2015-08-01

    We describe a simplified method to detect anterior lenticonus. Three eyes of 2 patients with anterior lenticonus, plus 16 eyes from 16 healthy controls underwent Scheimpflug imaging of their anterior segment with Pentacam. The anterior capsule apex angle was manually identified and automatically measured by AutoCAD. The mean angle was 173.06° (SD: 1.91) in healthy subjects, and 158.33° (SD: 3.05) in anterior lenticonus eyes. The angle obtained from patients was more than 3 SD steeper than those from healthy subjects. The apical angle calculation method seems to discriminate well between normal eyes and eyes suspected of having anterior lenticonus. Copyright © 2013 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  16. Cystercercus larva in the anterior chamber of the eye of a 7year o

    African Journals Online (AJOL)

    user

    infestation should be considered when children present with features of ocular inflammation. INTRODUCTION ... dogs (T. solium, Echinococcus), cows (T. saginata), rodents. (Hymenolepsis), and fish (Diphyllobothrium ... infestation while involvement of the anterior chamber is said to be unusual. 2,3. Symptoms of ocular ...

  17. Hematoporphyrin derivative photoradiation treatment of experimental malignant melanoma in the anterior chamber of the rabbit

    NARCIS (Netherlands)

    Franken, K. A.; van Delft, J. L.; Dubbelman, T. M.; de Wolff-Rouendaal, D.; Oosterhuis, J. A.; Star, W. M.; Marijnissen, H. P.

    1985-01-01

    The effects of Hematoporphyrin Derivative Photoradiation Therapy (HpD-PRT) on Greene's amelanotic melanoma implanted into the anterior chamber of rabbits have been examined by biomicroscopy, fluorescein angiography and histopathology. The tumors were irradiated 24 hours after injection of HpD when

  18. Iris-fixated anterior chamber phakic intraocular lens for myopia moves posteriorly with mydriasis.

    NARCIS (Netherlands)

    Cruysberg, L.P.J.; Doors, M.; Berendschot, T.T.; Brabander, J. De; Webers, C.A.; Nuijts, R.M.

    2009-01-01

    PURPOSE: To elucidate the physiological characteristics of eyes implanted with iris-fixated anterior chamber phakic intraocular lenses (pIOLs), which are increasingly being used for the correction of higher myopic and hyperopic refractive errors. METHODS: In a case series of 20 patients (39 eyes),

  19. Upregulation of CD94 on CD8+T Cells in Anterior Chamber Immune Deviation

    NARCIS (Netherlands)

    He, H.; Yang, P.; Jiang, L.; Zhang, J.; Zhao, Changlin; Chen, L.; Lin, X.; Zhou, H.; Kijlstra, A.

    2008-01-01

    Background CD8+ regulatory T cells (Treg) have been considered to be involved in a model of ocular-induced tolerance, known as anterior chamber-associated immune deviation (ACAID). The phenotype and characteristics of CD8+Treg in ACAID remain only poorly understood. Recent studies have reported that

  20. OVA-specific CD8(+)T cells do not express granzyme B during anterior chamber associated immune deviation

    NARCIS (Netherlands)

    Ren, Y.; Yang, P.; Li, B.; Gao, Y.; Zhou, H.; Huang, X.; Zhu, L.; Kijlstra, A.

    2006-01-01

    To examine antigen (Ag)-specific CTL response during anterior chamber associated immune deviation (ACAID). Methods OVA or OVA257-264 peptide was injected into the anterior chamber (AC) of C57BL/6 mice. There were 16 mice in each ACAID group induced with OVA or OVA257-264 peptide. The mice were

  1. Effect of phacoemulsification on drainage angle status in angle closure eyes with or without extensive peripheral anterior synechiae.

    Science.gov (United States)

    Latifi, Golshan; Moghimi, Sasan; Eslami, Yadollah; Fakhraie, Ghasem; Zarei, Reza; Lin, Shan

    2013-01-21

    Purpose. To evaluate the anatomic effects of phacoemulsification on drainage angle status in primary angle closure glaucoma (PACG) using anterior segment optical coherence tomography (AS-OCT). Methods. A total of 62 eyes of 58 patients underwent cataract surgery in Farabi Rye Hospital, Tehran, Iran. Patients were examined postoperatively on day 1, week 1, and week 6. Indentation gonioscopy and AS-OCT were performed preoperatively and at 6 weeks after surgery. Main outcome measures were angle and anterior segment parameters by AS-OCT and amount of peripheral anterior synechiae (PAS) by gonioscopy. Thirty-five eyes had PAS =180 degrees (group 1) and 27 eyes had >180-degree synechial closure (group 2). Results. Mean age of the patients was 64.3±9.0 years. The mean extent of PAS was significantly reduced from 45.9 to 32.2 degrees (p180 degrees.

  2. Effect of topiramate on choroidal thickness and anterior chamber parameters in the treatment of patients with migraine.

    Science.gov (United States)

    Gok, Mustafa; Ozdemir, Ozdemir

    2017-12-01

    To investigate the effects of topiramate on choroidal thickness and anterior chamber parameters using optical coherence tomography in the treatment of patients with migraine. A total of 22 eyes of 22 adults (12 females, 10 males) diagnosed with migraine and scheduled to topiramate treatment for pain control were recruited in this prospective study. Choroidal thickness (CT), anterior chamber depth (ACD), anterior chamber angle (ACA), spherical refractive equivalent (SphEq) and intraocular pressure (IOP) measurements were recorded at baseline (prior the topiramate therapy), first and second month visits for the statistical analysis. One-way ANOVA with repeated measures test was used for the statistical evaluation. Mean age of the patients was 40.2 ± 6.5 years. Mean CT at central fovea was 324 ± 47 μm initially, 341 ± 45 μm in the first month and 344 ± 46 μm in the second month, thus first and second month measures were significantly higher than base values (p < 0.001). There was also a slight increase in IOP values among baseline (15.5 ± 2.4 mmHg) and follow-up visits (17.5 ± 2.6 mmHg, 19.0 ± 3.3 mmHg, respectively, ` p = 0.001). Baseline ACD (3.66 ± 0.22 mm) measures significantly decreased at the first month (3.63 ± 0.22 mm) and second month (3.62 ± 0.22 mm, p = 0.009). Also, a significant reduction was detected in the first (36.2 ± 4.9°) and second month (35.9 ± 5.1°) ACA measures comparing with baseline (39.1 ± 5.1°, p = 0.05). A significant myopic shift was determined in the first and second month SphEq values (-0.08 ± 0.6, -0.10 ± 0.6, respectively, p = 0.05). The study revealed increased CT and altered anterior chamber parameters and IOP due to topiramate therapy. Therefore, the patients using topiramate should be carefully monitored by an ophthalmologist considering the possible side effects.

  3. Acanthamoeba keratitis with granulomatous reaction involving the stroma and anterior chamber.

    Science.gov (United States)

    Mietz, H; Font, R L

    1997-02-01

    Most cases of granulomatous reaction to Descemet membrane are caused by disciform herpes simplex and mycotic keratitis. To our knowledge, a clinicopathologic report of Acanthamoeba species infection has not been documented. We used standard histopathologic techniques, including light microscopy with special stains and indirect immunofluorescence. A granulomatous reaction with many multinucleated giant cells, some of which engulfed cysts of Acanthamoeba species, was present in the posterior corneal stroma and anterior chamber along the plane of Descemet membrane. A severe, acute, suppurative inflammatory response and areas of stromal necrosis also were present. The diagnosis of Acanthamoeba castellanii was confirmed by immunofluorescent studies. A granulomatous reaction to Descemet membrane and/or the corneal stroma may represent a specific tissue response to various infectious agents. Keratitis caused by Acanthamoeba species may be added to herpes simplex stromal keratitis and mycotic keratitis as a causative organism capable of producing a granulomatous reaction involving the stroma and anterior chamber.

  4. Analysis of iris structure and iridocorneal angle parameters with anterior segment optical coherence tomography in Fuchs' uveitis syndrome.

    Science.gov (United States)

    Basarir, Berna; Altan, Cigdem; Pinarci, Eylem Yaman; Celik, Ugur; Satana, Banu; Demirok, Ahmet

    2013-06-01

    To evaluate the differences in the biometric parameters of iridocorneal angle and iris structure measured by anterior segment optical coherence tomography (AS-OCT) in Fuchs' uveitis syndrome (FUS). Seventy-six eyes of 38 consecutive patients with the diagnosis of unilateral FUS were recruited into this prospective, cross-sectional and comparative study. After a complete ocular examination, anterior segment biometric parameters were measured by Visante(®) AS-OCT. All parameters were compared between the two eyes of each patient statistically. The mean age of the 38 subjects was 32.5 ± 7.5 years (18 female and 20 male). The mean visual acuity was lower in eyes with FUS (0.55 ± 0.31) than in healthy eyes (0.93 ± 0.17). The central corneal thickness did not differ significantly between eyes. All iridocorneal angle parameters (angle-opening distance 500 and 750, scleral spur angle, trabecular-iris space (TISA) 500 and 750) except TISA 500 in temporal quadrant were significantly larger in eyes with FUS than in healthy eyes. Anterior chamber depth was deeper in the eyes with FUS than in the unaffected eyes. With regard to iris measurements, iris thickness in the thickest part, iris bowing and iris shape were all statistically different between the affected eye and the healthy eye in individual patients with FUS. However, no statistically significant differences were evident in iris thickness 500 μm, thickness in the middle and iris length. There were significant difference in iris shape between the two eyes of patients with glaucoma. AS-OCT as an imaging method provides us with many informative resultsin the analysis of anterior segment parameters in FUS.

  5. The influence factors and management of anterior chamber gas bubble emergence during femtosecond flap creation for LASIK

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    Zhong-Ji Li

    2017-12-01

    Full Text Available AIM: To study the influence factors and management of anterior chamber gas bubble during femtosecond flap creation for laser-assisted in situ keratomileusis(LASIK. METHODS: Totally 9 671 eyes of 4 859 patients with femtosecond LASIK were included in this study. Preoperative, intraoperative and postoperative parameters of anterior chamber gas bubble patients were analyzed and compared. RESULTS: A total of 51 cases(0.53%occurred anterior chamber gas bubble during femtosecond flap creation. There was no statistical difference between uncorrected visual acuity of postoperative 1mo(-0.076±0.09and preoperative best corrected visual acuity(-0.08±0.04; t=-0.34,P=0.74. And 33 eyes(65%did not affect the pupil tracking, but there were 18 eyes(35%unable to track the pupil successfully. There was no statistical difference in uncorrected visual acuity of postoperative 1mo between trace group(-0.06±0.08and no trace group(-0.11±0.09; t=1.82, P=0.07. The highest incidence of anterior chamber gas bubble was at 9 point, followed by 3 point. There were no statistical differences in spherical equivalent refraction, corneal curvature, corneal diameter, anterior chamber volume, anterior chamber depth and intraoperative femtosecond laser energy between anterior chamber gas bubble eyes and the contralateral eyes(P>0.05. CONCLUSION: Anterior chamber gas bubble formation during femtosecond flap creation for LASIK is an uncommon event. It may affect the eye tracking. There is no obvious effect on early postoperative visual acuity if intraoperative disposed properly. The direct or indirect factors of anterior chamber gas bubble formation are unclear.

  6. Nitric oxide levels in the anterior chamber of vitrectomized eyes with silicon oil

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    Paulo Escarião

    2013-10-01

    Full Text Available PURPOSE: To investigate the nitric oxide levels in the anterior chamber of eyes who underwent pars plana vitrectomy (PPV with silicone oil. METHODS: Patients who underwent PPV with silicon oil injection, from february 2005 to august 2007, were selected. Nine patients (nine eyes participated in the study (five women and four men. Nitric oxide concentration was quantified after the aspiration of aqueous humor samples during the procedure of silicon oil removal. Data such as: oil emulsification; presence of oil in the anterior chamber; intraocular pressure and time with silicone oil were evaluated. Values of p <0.05 were considered to be statistically significant. RESULTS: A positive correlation between nitric oxide concentration and time with silicon oil in the vitreous cavity (r=0.799 was observed. The nitric oxide concentration was significantly higher (p=0.02 in patients with silicon oil more than 24 months (0.90µmol/ml ± 0.59, n=3 in the vitreous cavity comparing to patients with less than 24 months (0.19µmol/ml ± 0.10, n=6. CONCLUSION: A positive correlation linking silicone oil time in the vitreous cavity with the nitric oxide concentration in the anterior chamber was observed.

  7. PARS PLANA VITRECTOMY WITH ANTERIOR CHAMBER VERSUS GORE-TEX SUTURED POSTERIOR CHAMBER INTRAOCULAR LENS PLACEMENT: LONG-TERM OUTCOMES.

    Science.gov (United States)

    Khan, M Ali; Gupta, Omesh P; Pendi, Kasim; Chiang, Allen; Vander, James; Regillo, Carl D; Hsu, Jason

    2018-01-16

    To compare clinical outcomes of combined pars plana vitrectomy (PPV) with anterior chamber intraocular lens (ACIOL) placement versus scleral fixation of a posterior chamber intraocular lens (PCIOL) using Gore-Tex suture. Retrospective, interventional case series of eyes undergoing combined PPV and IOL placement for retained lens material, aphakia, or dislocated IOL. Eyes with history of amblyopia, corneal opacity, retinal, or optic nerve disease were excluded. Outcome measures were change in visual acuity and occurrence of postoperative complications with minimum follow-up of 1 year. Sixty-three eyes of 60 patients were identified. Thirty-three eyes underwent combined PPV and ACIOL placement and 30 eyes underwent combined PPV and scleral fixation of a PCIOL using Gore-Tex suture. Mean follow-up was 502 ± 165 days (median 450, range 365-1,095 days). In the ACIOL group, mean visual acuity improved from 20/914 preoperatively to 20/50 postoperatively (P Gore-Tex suture were well tolerated. The techniques resulted in similar visual outcomes at minimum follow-up of 1 year.

  8. Incidence and Outcomes of Anterior Chamber Gas Bubble during Femtosecond Flap Creation for Laser-Assisted In Situ Keratomileusis

    Directory of Open Access Journals (Sweden)

    Sloan W. Rush

    2015-01-01

    Full Text Available Purpose. To report the incidence and outcomes of anterior chamber gas bubble formation during femtosecond laser flap creation for laser-assisted in situ keratomileusis (LASIK. Methods. The charts of 2,886 consecutive eyes that underwent femtosecond LASIK from May 2011 through August 2014 were retrospectively reviewed. The incidence, preoperative characteristics, intraoperative details, and postoperative outcomes were analyzed in subjects developing anterior chamber gas bubble formation during the procedure. Results. A total of 4 cases (0.14% developed anterior chamber gas bubble formation during femtosecond laser flap creation. In all four cases, the excimer laser was unable to successfully track the pupil immediately following the anterior chamber bubble formation, temporarily postponing the completion of the procedure. There was an ethnicity predilection of anterior chamber gas formation toward Asians (p=0.0055. An uncorrected visual acuity of 20/20 was ultimately achieved in all four cases without further complications. Conclusions. Anterior chamber gas bubble formation during femtosecond laser flap creation for LASIK is an uncommon event that typically results in a delay in treatment completion; nevertheless, it does influence final positive visual outcome.

  9. Spontaneous resolution of double anterior chamber with perforation of Descemet′s membrane in deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Arvind Venkatraman

    2012-01-01

    Full Text Available Deep anterior lamellar keratoplasty (DALK using Dr. Anwar′s big bubble technique was performed for a patient with granular dystrophy. Intraoperatively, a perforation of the Descemet′s membrane (DM was noted inferonasally. Though the surgery was completed, the donor graft appeared to have an intact endothelium, which was inadvertently left behind by the surgeon. Intraoperatively, there was a perforation of inferonasal DM and surgery was completed by inadvertently placing a donor with an intact endothelium. Postoperatively the patient presented with a complete DM detachment and a resultant double anterior chamber (DAC. In spite of two attempts at an air tamponade on the first and fifth post operative days, the DAC still persisted. Surprisingly, during the 6 th week follow up visit, there was a complete resolution of the DAC as well as total recovery of vision. This interesting case clearly exemplifies that, in spite of failed attempts at air tamponade, a DM detachment and a DAC due to DM perforation following a DALK procedure can resolve spontaneously with good visual outcome.

  10. Conservative treatment of Angle Class III malocclusion with anterior crossbite

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    João Hélder Ferreira de Aguiar

    2015-08-01

    Full Text Available Angle Class III malocclusion is characterized by anteroposterior dental discrepancy which might be associated or not with skeletal changes. Class III molar relationship is associated with vertical or lingually tipped mandibular incisors and a usually concave profile. These characteristics seriously affect facial esthetics and most frequently are the reason why patients seek orthodontic treatment. This case was presented to the committee of the Brazilian Board of Orthodontics and Facial Orthopedics (BBO as part of the requisites to become a BBO Diplomate.

  11. An unusual case of acute angle-closure glaucoma following deep anterior lamellar keratoplasty using the “big bubble” technique

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    Samir Jabbour

    2017-09-01

    Conclusions and importance: Inability to recognize stroma from Descemet membrane during the dissection of the “big bubble technique” can result in failure to evacuate the high-pressure Descemet membrane detachment, putting the patient at risk for acute angle closure glaucoma from occlusion of the pupil. Proper dissection of stroma from underlying DM is a challenging and crucial step in the “big bubble” technique. Several methods, such as the injection of small bubbles in the anterior chamber or the use of intra-operative anterior segment OCT could be employed to prevent such a complication.

  12. [Occlusal planes of Angle's class III malocclusion impact by anterior overbite].

    Science.gov (United States)

    He, Ping; Xiao, Danna; Cang, Song; Gao, Hui

    2014-06-01

    To investigate the correlation between Angle's class III patients' occlusion plane and anterior overbite by controlling the changes in occlusion plane during orthodontic treatment. In total, 90 Angle's class III adult orthodontic patients were selected as the experimental group, and 30 normal adults were selected as the control group. According to the overbite, the class III patients were divided into three groups, and 14 indicators were measured. ANOVA and multiple comparison analysis were used to analyze the difference between class III patients, and linear analysis was used to analyze the correlation between anterior overbite and anterior-posterior occlusion plane. In class Ill patients, posterior occlusion plane and anterior overbite size were negatively correlated (r = -0.24, P overbite size were positive correlated (r = 0.23, P overbite patients. During orthodontic treatment in different overbite class III patients, the vertical height of the posterior teeth and the rotation of the occlusion plane should be controlled.

  13. Primary anterior chamber intraocular lens for the treatment of severe crystalline lens subluxation.

    Science.gov (United States)

    Hoffman, Richard S; Fine, I Howard; Packer, Mark

    2009-10-01

    Subluxated cataractous and clear lenses are commonly treated by limbal or pars plana lensectomy followed by primary or secondary intraocular lens (IOL) implantation. Adjunctive capsular prosthetic devices have facilitated lens removal and IOL centration in these challenging cases but have also added complexity and potential complications to the procedure. Although crystalline lens extraction may be required to clear the visual axis in mild to moderate lens subluxations, we propose insertion of a primary anterior chamber IOL without lens extraction in severe subluxations when the eye is optically aphakic or can be made functionally aphakic following neodymium:YAG laser zonulysis. Two cases demonstrating this approach are presented.

  14. Loa loa in the anterior chamber of the eye: A case report

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    Barua P

    2005-01-01

    Full Text Available An unusual case of loiasis from Assam is reported here. Loa loa is a subcutaneous filarial parasite of man and is transmitted to humans by chrysops flies. The patient presented with foreign body sensation and visual disturbances of the right eye. Examination revealed a white coiled structure in the cornea.. Routine blood and other investigations were within normal limits. A live adult worm was extracted and identity was confirmed by microscopy to be Loa loa. Patient was treated with diethylcarbamazine and steroid. We found this case interesting as the worm was present in the anterior chamber - an unusual site and there were no other positive findings besides the lone worm.

  15. Nasolabial and Interincisal Angle Evaluation in Anterior Maxillary Distraction Osteogenesis: A Case Study

    Directory of Open Access Journals (Sweden)

    Tojan Chacko Thekkekara

    2014-01-01

    Full Text Available Maxillary hypoplasia is a common developmental problem in cleft lip and palate deformities. These deformities have traditionally been corrected by means of orthognathic surgery. Management of skeletal deformities in the maxillofacial region has been a challenge for maxillofacial surgeons and orthodontists. Distraction osteogenesis (DO is a surgical technique that uses body′s own repairing mechanisms for optimal reconstruction of the hard and soft tissues. We present four cases of anterior maxillary distraction osteogenesis with tooth-borne distraction device— Hyrax, which were analyzed retrospectively using cephalometrics. Changes in nasolabial angle and interincisal angle after distraction of anterior maxillary segment were studied to conclude that there was no much change in the the nasolabial angle while the interincisal angle showed marked improvement.

  16. Influence of deflection hole angle on effusion cooling in a real combustion chamber condition

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    Liu Xiao

    2015-01-01

    Full Text Available Fluid-solid coupling simulation is conducted to investigate the performance of effusion cooling in the real combustion chamber condition of strong rotation and primary holes. The wall temperature and film cooling effectiveness of different deflection angle is analyzed. From the results, it is concluded that the performance of effusion is better than conventional film cooling. The wall temperature and gradient is lower, the cooling efficiency is higher and the coolant is reduced by 20%, but pressure loss is slightly increased. The cooling effectiveness decreases behind primary holes because of local combustion. Comparison with the effect of deflection angle, the cooling performance of 60 deg deflection angle is best. The coolant is better attached to the wall downstream when the deflection angle is same as the rotating mainstream. In addition, the effect of deflection angle is not so significant on the coolant flow rate, but a large negative impact on the pressure loss. Although the cooling effectiveness of 60 deg deflection angle is highest, the total pressure recovery coefficient is lower. The maximum temperature drops about 70K and the outlet temperature distribution trends more consistent. So various factors should be taken into consideration when designing of deflection angle.

  17. Evaluation of Anterior Chamber Volume in Cataract Patients with Swept-Source Optical Coherence Tomography.

    Science.gov (United States)

    He, Wenwen; Zhu, Xiangjia; Wolff, Don; Zhao, Zhennan; Sun, Xinghuai; Lu, Yi

    2016-01-01

    Purpose. To evaluate the anterior chamber volume in cataract patients with Swept-Source Optical Coherence Tomography (SS-OCT) and its influencing factors. Methods. Anterior chamber volume of 92 cataract patients was evaluated with SS-OCT in this cross-sectional study. Univariate analyses and multiple linear regression were used to investigate gender, age, operated eye, posterior vitreous detachment, lens opacity grading, and axial length (AXL) related variables capable of influencing the ACV. Results. The average ACV was 139.80 ± 38.21 mm(3) (range 59.41 to 254.09 mm(3)). The average ACV was significantly larger in male patients than in female patients (P = 0.001). ACV was negatively correlated with age and LOCS III cortical (C) grading of the lens (Pearson's correlation analysis, r = -0.443, P ACV was also increased with AXL (Pearson's correlation analysis, r = 0.552, P ACV (F = 10.252  P ACV varied significantly among different subjects. Influencing factors that contribute to reduced ACV were female gender, increased age, LOCS III C grade, and shorter AXL.

  18. The changes of the interspace angle after anterior correction and instrumentation in adolescent idiopathic scoliosis patients

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    Fei Qi

    2007-10-01

    Full Text Available Abstract Background In idiopathic scoliosis patients, after anterior spinal fusion and instrumentation, the discs (interspace angle between the lowest instrumented vertebra (LIV and the next caudal vertebra became more wedged. We reviewed these patients and analyzed the changes of the angle. Methods By reviewing the medical records and roentgenograms of adolescent idiopathic scoliosis patients underwent anterior spinal fusion and instrumentation, Cobb angle of the curve, correction rate, coronal balance, LIV rotation, interspace angle were measured and analyzed. Results There were total 30 patients included. The mean coronal Cobb angle of the main curve (thoracolumbar/lumbar curve before and after surgery were 48.9° and 11.7°, respectively, with an average correction rate of 76.1%. The average rotation of LIV before surgery was 2.1 degree, and was improved to 1.2 degree after surgery. The interspace angle before surgery, on convex side-bending films, after surgery, at final follow up were 3.2°, -2.3°, 1.8° and 4.9°, respectively. The difference between the interspace angle after surgery and that preoperatively was not significant (P = 0.261, while the interspace angle at final follow-up became larger than that after surgery, and the difference was significant(P = 0.012. The interspace angle after surgery was correlated with that on convex side-bending films (r = 0.418, P = 0.022, and the interspace angle at final follow-up was correlated with that after surgery (r = 0.625, P = 0.000. There was significant correlation between the loss of the interspace angle and the loss of coronal Cobb angle of the main curve during follow-up(r = 0.483, P = 0.007. Conclusion The interspace angle could be improved after anterior correction and instrumentation surgery, but it became larger during follow-up. The loss of the interspace angle was correlated with the loss of coronal Cobb angle of the main curve during follow-up.

  19. A modification of the bisecting-angle technique for anterior periapical dental radiographs.

    Science.gov (United States)

    Monsour, P A

    1986-10-01

    A modification of the standard bisecting-angle technique for periapical views of incisor teeth is presented. The technique involves a constant x-ray cone position, which is perpendicular to the floor for maxillary incisors and parallel to the floor for mandibular incisors. The periapical film is held between the incisor teeth as if it were an occlusal film for all anterior periapical radiographs. Tracings from lateral skull radiographs, taken of dried skulls of various ages, were used to determine the optimal angle between the periapical film and the floor to produce a dimensionally accurate periapical view of the incisors. The technique is suggested as an alternative to the standard bisecting-angle technique and the parallel technique. It is intended for anterior periapical radiographs when clinical conditions make conventional techniques difficult. For example, it can be used in very young children, patients with gagging problems, and patients with narrow lower jaws or large muscular tongues.

  20. Ocular Toxicity after High-Dose Cefuroxime Injection into the Anterior Chamber

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    Harun Çakmak

    2016-08-01

    Full Text Available Cephalosporins are beta-lactam antibiotics and, like penicillin derivatives, they show bacteriostatic effect by disrupting bacterial cell wall synthesis. Cefuroxime is a second generation cephalosporin and the use of intracameral cefuroxime after cataract surgery has been widely used in the endophthalmitis prophylaxis. A 78-year-old male patient was operated for cataracts in both eyes about 8 years ago. Ocular trauma has occurred in the left eye nine months ago. Vitrectomy surgery combined with intraocular lens extraction was performed and the patient was left aphakic. Secondary intraocular lens implantation was performed. In this paper, we present postoperative ocular findings in a patient who was given cefuroxime into the anterior chamber 2.5 times higher than the recommended dose (25 mg/ml after secondary intraocular lens implantation.

  1. Aqueous humour dynamics in anterior chamber under influence of cornea indentation

    Science.gov (United States)

    Zuhaila, I.; Jiann, L. Y.; Sharidan, S.; Fitt, A.

    2017-04-01

    The existing temperature different between the cornea and the pupil induces the aqueous humour (AH) to circulate in the anterior chamber (AC). The buoyancy forces produced by the temperature gradient has driven the AH to flow. Previous studies have shown that cornea indentation changes the structure of the AC. This imply that the cornea indentation may change the fluid flow behaviour in the AC. A mathematical model of AH flow has been developed in order to analyse the fluid mechanics concerning the indentation of the cornea. Naiver-Stokes equations is used to describe the flow of AH in the AC. The governing equations have been solved numerically using finite element method. The results show that the cornea indentation has slow down the circulation the AH in the AC.

  2. Fluid mechanics of the human eye: aqueous humour flow in the anterior chamber.

    Science.gov (United States)

    Fitt, A D; Gonzalez, G

    2006-01-01

    We consider and compare the various different kinds of flow that may take place in the anterior chamber of a human eye. The physical mechanisms responsible for causing such flows may be classified as follows: (i) buoyancy-driven flow arising from the temperature difference between the anterior surface of the cornea and the iris, (ii) flow generated by the aqueous production of the ciliary body, (iii) flow generated by the interaction between buoyancy and gravity while sleeping while sleeping in a face-up position, (iv) flow generated by phakodenesis (lens tremor), (v) flow generated by Rapid Eye Movement (REM) during sleep. Each flow is studied using a traditional fluid mechanics/asymptotic analysis approach. We also assess the veracity of a hypothesis that was recently advanced [see Maurice, D.M., 1998. The Von Sallman Lecture 1996: An ophthalmological explanation of REM sleep. Exp. Eye. Res. 66, 139-145, for details] to suggest that, contrary to previous opinion, the purpose of REM during sleep is to ensure corneal respiration in the absence of the buoyant mixing that routinely takes place due to (i) above during waking conditions.

  3. [Contribution of confocal microscopy and anterior chamber OCT to the study of corneal endothelial pathologies].

    Science.gov (United States)

    Fayol, N; Labbé, A; Dupont-Monod, S; Dupas, B; Baudouin, C

    2007-04-01

    To describe the appearance of various endothelial diseases with in vivo confocal microscopy and anterior chamber optical coherence tomography (AC OCT). In this study, ten patients with five different corneal endothelial pathologies were evaluated. Three patients had cornea guttata, three had corneal endothelial precipitates, two had irido-corneo-endothelial (ICE) syndrome, one had endothelial folds, and one had breaks in the Descemet membrane. All patients had bilateral ophthalmologic examinations, in vivo confocal microscopy, and AC OCT analysis. In cases of cornea guttata, AC OCT showed a finely embossed line corresponding to the empty intercellular cavities found with in vivo confocal microscopy. Corneal endothelium precipitates had the aspect of round formations suspended with the endothelium. Iris atrophy and irido-corneal synechiae resulting from ICE syndrome were precisely visualized with the AC OCT. High-resolution images of the anterior segment could be obtained using the AC OCT. Associated with in vivo confocal microscopy, these two new imaging techniques provide a precise evaluation of endothelial pathologies.

  4. UBM-guided chamber angle surgery for glaucoma management: an experimental study.

    Science.gov (United States)

    Dietlein, T S; Engels, B F; Jacobi, P C; Krieglstein, G K

    2003-04-01

    The aim of this experimental study was to investigate the potential of ultrasound bimicroscopy (UBM)-guided chamber angle surgery as an alternative or supplement to gonioscopy and intraocular microendoscopy for intraoperative control. In 15 porcine cadaver eyes, mechanical goniopuncture or punctual Er:YAG laser trabecular ablation was performed without operating microscope or gonioscopy, but with real-life ultrasound biomicroscopy monitoring with a 50 MHz transducer. Intraoperative localization of the microsurgical instruments and tissue-instrument contact were qualitatively evaluated. The instruments could be clearly visualized within the chamber angle and disturbing artefacts were only minimal when using mechanically fixed instruments in slow motion. Topographic localization, tissue contact, and penetration depth of the instruments entering the scleral were well illustrated as far as the technical resolution limits of UBM would allow. UBM can be used intraoperatively to monitor the correct manoeuvring of microsurgical instruments in selected ab interno procedures. Some adaptations and further modifications of the technique presented here will be necessary before UBM-guided surgery can be considered for clinical use in humans.

  5. 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

  6. Anterior Chamber-Associated Immune Deviation (ACAID: An Acute Response to Ocular Insult Protects from Future Immune-Mediated Damage?

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    Robert E. Cone

    2009-01-01

    Full Text Available The “immune privilege” that inhibits immune defense mechanisms that could lead to damage to sensitive ocular tissue is based on the expression of immunosuppressive factors on ocular tissue and in ocular fluids. In addition to this environmental protection, the injection of antigen into the anterior chamber or infection in the anterior chamber induces a systemic suppression of potentially damaging cell-mediated and humoral responses to the antigen. Here we discuss evidence that suggests that Anterior Chamber-Associated Immune Deviation (ACAID a is initiated by an ocular response to moderate inflammation that leads to a systemic immunoregulatory response. Injection into the anterior chamber induces a rise in TNF-α and MCP-1 in aqueous humor and an infiltration of circulating F4/80 + monocytes that home to the iris. The induction of ACAID is dependent on this infiltration of circulating monocytes that eventually emigrate to the thymus and spleen where they induce regulatory T cells that inhibit the inductive or effector phases of a cell-mediated immune response. ACAID therefore protects the eye from the collateral damage of an immune response to infection by suppressing a future potentially damaging response to infection.

  7. Blunt needle revision with viscoelastic materials via the anterior chamber for early failed filtering blebs after trabeculectomy

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    Yamagami H

    2012-06-01

    Full Text Available Nozomi Kinoshita, Ayumi Ota, Fumihiko Toyoda, Hiroko Yamagami, Akihiro KakehashiDepartment of Ophthalmology, Saitama Medical Center, Jichi Medical University, Saitama, JapanPurpose: To report a new technique of blunt needle revision with viscoelastic materials via the anterior chamber for the treatment of early failed filtering blebs and elevated intraocular pressure after trabeculectomy, in which digital ocular massage and laser suture lysis have been ineffective.Methods: A 27-gauge blunt needle attached to a syringe containing viscoelastic material was inserted into the anterior chamber from the inferior paracentesis. The needle tip was inserted into the subscleral flap space from the filtering fistula at the anterior chamber side, and the scleral flap was lifted bluntly. The needle tip was then inserted into the subconjunctival space where the viscoelastic agent was injected and the adhesion between the sclera and conjunctiva was separated bluntly. Blunt needle revision via the anterior chamber was performed 14 times in six eyes of six patients at Saitama Medical Center, Jichi Medical University from January 2007 to May 2009. All procedures were performed within 1 month after trabeculectomy.Results: The intraocular pressure remained 21 mmHg or lower for more than 6 months in three of six eyes. Slight bleeding from the iris occurred in one of the 14 procedures, and hypotony (intraocular pressure below 5 mmHg occurred in one of the 14 procedures. No serious complications developed.Conclusion: Blunt needle revision via the anterior chamber for early failed filtering blebs is a new, simple, and safe procedure.Keywords: glaucoma, trabeculectomy, filtering bleb, needle revision, blunt needle

  8. Anterior chamber depth and iris and lens position before and after phacoemulsification in eyes with a short or long axial length.

    Science.gov (United States)

    Muzyka-Woźniak, Maria; Ogar, Angelika

    2016-04-01

    To evaluate changes in anterior segment parameters after phacoemulsification in short eyes and long eyes. Spektrum Eye Clinic, Wrocław, Poland. Prospective comparative study. Anterior segment parameters were examined before and after phacoemulsification in 3 groups of eyes as follows: short (axial length [AL] 25.5 mm) with optical biometry based on partial coherence interferometry (IOLMaster) and anterior segment optical coherence tomography (Visante). The study comprised 20 short eyes, 22 normal eyes, and 19 long eyes. The anterior chamber angle increased after surgery in all eyes (P position after phacoemulsification was larger in short eyes than in normal or long eyes (mean change 0.93 mm, 0.70 mm, and 0.43 mm, respectively) (P position after phacoemulsification in relation to the iris was smaller in short eyes (mean 0.51 mm) than in normal or long eyes (mean 0.82 mm and 1.10 mm, respectively) (P position occurred in short eyes. The largest change in the lens versus the intraocular lens (IOL) position occurred in long eyes, with the IOL moving back from the iris. Optical biometry might underestimate the postoperative ACD. Neither author has a financial or proprietary interest in any material or method mentioned. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  9. Technical Note: An investigation of polarity effects for wide-angle free-air chambers

    International Nuclear Information System (INIS)

    Shen, H.; Ross, C. K.; Culberson, W. S.

    2016-01-01

    Purpose: Wide-angle free-air chambers (WAFACs) are used as primary standard measurement devices for establishing the air-kerma strength of low-energy, low-dose rate brachytherapy seeds. The National Research Council of Canada (NRC) is commissioning a primary standard wide-angle free-air chamber (NRC WAFAC) to serve the calibration needs of Canadian clients. The University of Wisconsin has developed a similar variable-aperture free-air chamber (UW VAFAC) to be used as a research tool. As part of the NRC commissioning, measurements were carried out for both polarities of the applied bias voltage and the resulting effects were observed to be very large. Similar effects were identified with the UW VAFAC. The authors describe the measurements carried out to determine the underlying causes of the polarity effect and the approach used to eliminate it. Methods: The NRC WAFAC is based on the WAFAC design developed at the National Institute of Standards and Technology in the USA. Charge measurements for 125 I and 241 Am sources were carried out for both negative and positive polarities on the NRC WAFAC and UW VAFAC. Two aperture sizes were also investigated with the UW VAFAC. In addition, measurements on the NRC WAFAC were carried out with a small bias between the collecting electrode and the shield foil at the downstream end of the chamber. To mitigate all of the polarity effects, the downstream surface of the collecting electrode was covered with a thin layer of graphite on both the NRC and UW chambers. Results: Both chamber designs showed a difference of more than 30 % between the charge collected with positive and negative bias voltages for the smallest electrode separation. It was shown for the NRC WAFAC that charge could be collected in the small gap downstream of the collecting volume by applying a voltage between the shield foil and the collecting electrode, even though an insulating foil (Mylar or polyimide film) separated the conducting surface from the small gap

  10. A computational model to investigate the effect of pennation angle on surface electromyogram of Tibialis Anterior.

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    Diptasree Maitra Ghosh

    Full Text Available This study has described and experimentally validated the differential electrodes surface electromyography (sEMG model for tibialis anterior muscles during isometric contraction. This model has investigated the effect of pennation angle on the simulated sEMG signal. The results show that there is no significant effect of pennation angle in the range 0° to 20° to the single fibre action potential shape recorded on the skin surface. However, the changes with respect to pennation angle are observed in sEMG amplitude, frequency and fractal dimension. It is also observed that at different levels of muscle contractions there is similarity in the relationships with Root Mean Square, Median Frequency, and Fractal Dimension of the recorded and simulated sEMG signals.

  11. Capsid Mutated Adeno-Associated Virus Delivered to the Anterior Chamber Results in Efficient Transduction of Trabecular Meshwork in Mouse and Rat.

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    Barbara Bogner

    Full Text Available Adeno associated virus (AAV is well known for its ability to deliver transgenes to retina and to mediate improvements in animal models and patients with inherited retinal disease. Although the field is less advanced, there is growing interest in AAV's ability to target cells of the anterior segment. The purpose of our study was to fully articulate a reliable and reproducible method for injecting the anterior chamber (AC of mice and rats and to investigate the transduction profiles of AAV2- and AAV8-based capsid mutants containing self-complementary (sc genomes in the anterior segment of the eye.AC injections were performed in C57BL/6 mice and Sprague Dawley rats. The cornea was punctured anterior of the iridocorneal angle. To seal the puncture site and to prevent reflux an air bubble was created in the AC. scAAVs expressing GFP were injected and transduction was evaluated by immunohistochemistry. Both parent serotype and capsid modifications affected expression. scAAV2- based vectors mediated efficient GFP-signal in the corneal endothelium, ciliary non-pigmented epithelium (NPE, iris and chamber angle including trabecular meshwork, with scAAV2(Y444F and scAAV2(triple being the most efficient.This is the first study to semi quantitatively evaluate transduction of anterior segment tissues following injection of capsid-mutated AAV vectors. scAAV2- based vectors transduced corneal endothelium, ciliary NPE, iris and trabecular meshwork more effectively than scAAV8-based vectors. Mutagenesis of surface-exposed tyrosine residues greatly enhanced transduction efficiency of scAAV2 in these tissues. The number of Y-F mutations was not directly proportional to transduction efficiency, however, suggesting that proteosomal avoidance alone may not be sufficient. These results are applicable to the development of targeted, gene-based strategies to investigate pathological processes of the anterior segment and may be applied toward the development of gene

  12. Endothelial Cell Loss after Phacoemulsification according to Different Anterior Chamber Depths.

    Science.gov (United States)

    Hwang, Hyung Bin; Lyu, Byul; Yim, Hye Bin; Lee, Na Young

    2015-01-01

    Purpose. To compare the loss of corneal endothelial cells after phacoemulsification according to different anterior chamber depths (ACDs). Methods. We conducted a prospective study on 135 eyes with senile cataracts. Eyes with nuclear density grades of 2 to 4 were divided into three groups according to ACD: ACD I, 1.5 ACD ≤ 2.5 mm; ACD II, 2.5 ACD ≤ 3.5 mm; or ACD III, 3.5 ACD ≤ 4.5 mm. Intraoperative mean cumulative dissipated energy (CDE) was measured. Clinical examinations included central corneal thickness (CCT) and endothelial cell count (ECC) preoperatively and 2 months postoperatively. Results. There were no significant differences in CDE among the ACD groups (P > 0.05). Endothelial cell loss was significantly higher in ACD I than in ACD III in grades 3 and 4 cataract density groups 2 months after phacoemulsification (P ACD I group compared to the ACD II and III groups 2 months postoperatively, but the difference was not statistically significant. Conclusions. Eyes with shallow ACDs, especially those with relatively hard cataract densities, can be vulnerable to more corneal endothelial cell loss in phacoemulsification surgery.

  13. Comparison of IOL Master contact and immersion A-scan ultrasound measurements of anterior chamber depth

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    Min Xu

    2015-07-01

    Full Text Available AIM: To compare the results of IOL Master, contact and immersion A-scan ultrasound measurements for anterior chamber depth(ACD, and evaluate the difference and consistency.METHODS:Fifty-eight cases(98 eyeswith age-related cataract during July to October in 2013 did the A-scan ultrasound with contact and immersion measurements and IOL Master to get the results of ACD. Difference in measurements between methods was assessed using the variance analysisi. Consistency was assessed using Bland-Altman.RESULTS: The ACD measured by IOL Master was 2.31~3.90mm, the mean was 3.03±0.38mm. The ACD measured by contact A-scan ultrasound was 1.51~4.06mm, the mean was 2.88±0.56mm. The ACD measured by immersion A-scan ultrasound was 1.99~4.17mm, the mean was 3.17±0.38mm. The results of IOL Master and contact A-scan ultrasound had statistical differences(P=0.022P=0.031P=0.000CONCLUSION: The rank of ACD of patients with cataract is immersion A-scan ultrasound, IOL Master and contact A-scan ultrasound. The consistency is poor, and the three methods can't be interchanged clinically.

  14. Central corneal thickness and anterior chamber depth measurement by Sirius® Scheimpflug tomography and ultrasound

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    Jorge J

    2013-02-01

    Full Text Available J Jorge,1 JL Rosado,2 JA Díaz-Rey,1 JM González-Méijome11Clinical and Experimental Optometry Research Laboratory, Center of Physics (Optometry, School of Sciences, University of Minho, Braga, 2Opticlinic, Lisboa, PortugalBackground: The purpose of this study was to compare the accuracy of the new Sirius® Scheimpflug anterior segment examination device for measurement of central corneal thickness (CCT and anterior chamber depth (ACD with that of CCT measurements obtained by ultrasound pachymetry and ACD measurements obtained by ultrasound biometry, respectively.Methods: CCT and ACD was measured in 50 right eyes from 50 healthy subjects using a Sirius Scheimpflug camera, SP100 ultrasound pachymetry, and US800 ultrasound biometry.Results: CCT measured with the Sirius was 546 ± 39 µm and 541 ± 35 µm with SP100 ultrasound pachymetry (P = 0.003. The difference was statistically significant (mean difference 4.68 ± 10.5 µm; limits of agreement −15.8 to 25.20 µm. ACD measured with the Sirius was 2.96 ± 0.3 mm compared with 3.36 ± 0.29 mm using US800 ultrasound biometry (P < 0.001. The difference was statistically significant (mean difference −0.40 ± 0.16 mm; limits of agreement −0.72 to 0.07 mm. When the ACD values obtained using ultrasound biometry were corrected according to the values for CCT measured by ultrasound, the agreement increased significantly between both technologies for ACD measurements (mean difference 0.15 ± 0.16 mm; limits of agreement −0.16 to 0.45 mm.Conclusion: CCT and ACD measured by Sirius and ultrasound methods showing good agreement between repeated measurements obtained in the same subjects (repeatability with either instrument. However, CCT and ACD values, even after correcting ultrasound ACD by subtracting the CCT value obtained with either technology should not be used interchangeably.Keywords: Scheimpflug corneal tomography, ultrasound biometry, ultrasound pachymetry, limits of agreement

  15. Moorfields technique of donor cornea mounting for femtosecond-assisted keratoplasty: use of viscoelastic in the artificial anterior chamber.

    Science.gov (United States)

    Iovieno, Alfonso; Chowdhury, Vivek; Stevens, Julian D; Maurino, Vincenzo

    2012-07-01

    Appropriate mounting and cutting of the donor sclero-corneal cap is often cumbersome during femtosecond laser-assisted keratoplasty. The authors describe a technique for donor cornea femtosecond laser cutting using ophthalmic viscoelastic devices. The donor sclero-corneal cap is mounted on the artificial anterior chamber using a dispersive ophthalmic viscoelastic device instead of saline solution. The chances of artificial anterior chamber pressure loss, inadequate applanation, and fluid leaks are consistently reduced with the use of dispersive ophthalmic viscoelastic devices. The speed of donor femtosecond laser cutting is increased. The viscosity and elasticity of dispersive ophthalmic viscoelastic devices greatly assist the procedure with regard to ease of applanation, corneal endothelium protection, and decreased distortion of the applanated cornea. Copyright 2012, SLACK Incorporated.

  16. Comparison of the Results of Secondary Anterior Chamber and Secondary Scleral-Fixated Intraocular Lens Implantation in Complicated Phacoemulsification Cases

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    Nimet Yeşim Erçalık

    2014-03-01

    Full Text Available Objectives: To compare the visual prognosis and postoperative complication rates of secondary anterior chamber (AC IOL and scleralfixated (SF intraocular lenses (IOL after complicated phacoemulsification surgery. Materials and Methods: Thirty eyes of thirty patients were reviewed for this retrospective study. The patients with secondary AC IOL implantation formed group 1 (n=15, and the patients with secondary SF IOL implantation formed group 2 (n=15. Best-corrected visual acuity (BCVA with Snellen chart, biomicroscopic examination, intraocular pressure (IOP measurement with applanation tonometer, gonioscopy performed by Goldmann’s 3-mirror contact lens, and fundus examination were performed preoperatively in all patients. Results: There was no statistically significant difference in postoperative BCVA (p=0.492 and postoperative success (BCVA not changed or better postoperatively between the 2 groups (p=0.598. Postoperative success rate was 80% in group 1 and 93.7% in Group 2. The postoperative cylindrical power of the eyes did not differ significantly between the groups (p=0.220. The postoperative complications in group 1 were as follows: transient corneal edema in 5 eyes, transient IOP elevation in 2 eyes, postoperative fibrinous reaction in the anterior chamber in one eye, late-onset secondary glaucoma in one eye, hyphema in one eye, cystoid macular edema in one eye, vitreous prolapse into the anterior chamber in one eye, and IOL malposition in one eye. The postoperative complications in group 2 were as follows: transient corneal edema in 3 eyes, vitreous prolapse into the anterior chamber in 2 eyes, IOL malposition in 2 eyes, transient IOP elevation in one eye, and retinal detachment in one eye. Conclusion: In this study, both IOL types were observed to be preferable in cases without adequate capsular support following complicated cataract surgery. However, further studies with large numbers of patients are needed to define the best choice

  17. Anterior chamber gas bubbles during femtosecond laser flap creation in LASIK: video evidence of entry via trabecular meshwork.

    Science.gov (United States)

    Soong, H Kaz; de Melo Franco, Rafael

    2012-12-01

    Femtosecond laser photodisruption of corneal stroma during laser in situ keratomileusis flap creation is accompanied by the formation of cavitation gas bubbles consisting of carbon dioxide and water vapor. Entry of these bubbles into the anterior chamber is an infrequent complication. We present video evidence that these bubbles enter via the trabecular meshwork. Neither author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  18. Anterior chamber depth and refractive change in late postoperative capsular bag distension syndrome: a retrospective analysis.

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    Min Kyu Yang

    Full Text Available To assess the characteristic findings and effects of laser capsulotomy in patients with late postoperative capsular bag distension syndrome (CBDS.Twenty patients diagnosed with late postoperative CBDS between July 2010 and August 2013 were retrospectively reviewed. Before and 1 week after capsulotomy, changes in the anterior chamber depth (ACD were assessed using ultrasound biomicroscopy. Changes in the refractive status and uncorrected visual acuity (UCVA were also measured 1 week and 1 month after capsulotomy. For patients who received bilateral cataract surgery, preoperative ACD and axial length measured by IOLMaster were compared between the two eyes.Twenty-two eyes from 20 patients who had undergone laser capsulotomy showed a mean UCVA improvement of 0.27 ± 0.24 logMAR (range, 0.00-0.90. ACD was increased by an average of +0.04 mm (95% confidence interval, +0.01 to +0.06 mm, p = 0.034, equivalent to predicted refractive change of +0.10 D. The discrepancy between actual (+1.33 D and predicted refractive change after capsulotomy suggests that refractive change may not be generated from IOL displacement in late postoperative CBDS. Preoperative ACD was deeper in the eye with late postoperative CBDS in all bilaterally pseudophakic patients (mean, 3.68 mm vs. 3.44 mm in the fellow eye, p = 0.068.Late postoperative CBDS showed refractive changes that were resolved successfully after laser capsulotomy. The convex lens effects of opalescent material in the distended capsular bag may play a major role in myopic shift. A larger preoperative ACD is possibly associated with the development of late postoperative CBDS.

  19. Effect of myopic adolescents wearing orthokeratology lens on the corneal surface curvature radius and anterior chamber depth

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    Qian Yu

    2017-06-01

    Full Text Available AIM: To analyze the effect of myopic adolescents wearing orthokeratology lens on the corneal surface curvature radius and anterior chamber depth. METHODS: Totally 120 cases of adolescent myopia were selected, among them 58 cases with 116 eyes were divided into 11-14 years old group and 62 cases with 124 eyes were 15-18 years old group according to the age. They were treated with long-term orthokeratology lens treatment, and two groups of patients were observed before wearing lens(T0, wearing for 6mo(T1, 12mo(T2for uncorrected visual acuity, the average refractive degree improvement, the central corneal thickness, corneal curvature changes and the incidence of complications. RESULTS: The uncorrected visual acuity of the two groups at 12mo after wearing were better than that at 6mo which was better than that before wearing; the diopter had the same trend. The uncorrected visual acuity and the diopter of the 11-14 years old group at 6 and 12mo was better than those of 15-18 years old group with significant difference(PP>0.05. The corneal anterior surface curvature of the two groups at 12mo after wearing were more than that at 6mo which was more than that before wearing. The axial length of the 11-14 years old group was longer than that of the 15-18 years old group with significant difference(PP>0.05. There was no significant difference on the anterior chamber depth between the two groups at different time or between before and after wearing(P>0.05.CONCLUSION: Long-term wearing orthokeratology lenses have a significant effect for control ling juvenile myopia, and can improve the corneal anterior surface curvature, especially in the lower age group, and has no significant effect on the anterior chamber depth.

  20. The clinical outcomes of surgical management of anterior chamber migration of a dexamethasone implant (Ozurdex®).

    Science.gov (United States)

    Kang, Hyunseung; Lee, Min Woo; Byeon, Suk Ho; Koh, Hyoung Jun; Lee, Sung Chul; Kim, Min

    2017-09-01

    Our purpose was to describe the clinical course, and individualized management approaches, of patients with migration of a dexamethasone implant into the anterior chamber. This was a retrospective review of four patients with seven episodes of anterior chamber migration of a dexamethasone implant. After 924 intravitreal dexamethasone injections, anterior migration of the implant occurred in four eyes of four patients (0.43%). All four eyes were pseudophakic: one eye had a posterior chamber intraocular lens in the capsular bag but in a post-laser posterior capsulotomy state, two eyes had a sulcus intraocular lens (IOL), and one eye had an iris-fixated retropupillary IOL. All eyes had a prior vitrectomy and no lens capsule. The time interval from injection to detection of the implant migration ranged from 2 to 6 weeks. Of the four eyes with corneal edema, only one eye required a corneal transplantation, although it was unclear whether the implant migration was the direct cause of the corneal decompensation because the patient had a history of bullous keratopathy resulting from an extended history of uveitis. All patients underwent surgical intervention: two patients with a repositioning procedure, and the other two patients with removal due to repeated episodes, although surgical removal was not always necessary to reverse the corneal complications. In our study, not all patients required surgical removal of the implants. Repositioning the implant back into the vitreous cavity may be considered as an option in cases involving the first episode with no significant corneal endothelial decompensation. Considering potential anterior segment complications and the loss of drug effectiveness together, an individualized approach is recommended to obtain the best treatment outcomes and to minimize the risk of corneal complications.

  1. Does flexible tunnel drilling affect the femoral tunnel angle measurement after anterior cruciate ligament reconstruction?

    Science.gov (United States)

    Muller, Bart; Hofbauer, Marcus; Atte, Akere; van Dijk, C Niek; Fu, Freddie H

    2015-12-01

    To quantify the mean difference in femoral tunnel angle (FTA) as measured on knee radiographs between rigid and flexible tunnel drilling after anatomic anterior cruciate ligament (ACL) reconstruction. Fifty consecutive patients that underwent primary anatomic ACL reconstruction with a single femoral tunnel drilled with a flexible reamer were included in this study. The control group was comprised of 50 patients all of who underwent primary anatomic ACL reconstruction with a single femoral tunnel drilled with a rigid reamer. All femoral tunnels were drilled through a medial portal to ensure anatomic tunnel placement. The FTA was determined from post-operative anterior-to-posterior (AP) radiographs by two independent observers. A 5° difference between the two mean FTA was considered clinically significant. The average FTA, when drilled with a rigid reamer, was 42.0° ± 7.2°. Drilling with a flexible reamer resulted in a mean FTA of 44.7° ± 7.0°. The mean difference of 2.7° was not statistically significant. The intraclass correlation coefficient for inter-tester reliability was 0.895. The FTA can be reliably determined from post-operative AP radiographs and provides a useful and reproducible metric for characterizing femoral tunnel position after both rigid and flexible femoral tunnel drilling. This has implications for post-operative evaluation and preoperative treatment planning for ACL revision surgery. IV.

  2. The anterior chamber angle width in adults in a tertiary eye hospital ...

    African Journals Online (AJOL)

    2011-03-25

    Mar 25, 2011 ... Materials and Methods: Consecutive new adult patients (aged ≥21 years) seen between March and July 2006 were the subjects of this study. Exclusion criteria included refusal to consent to the test, previous intraocular surgery that could distort ... lead to blindness but their treatment approach is basically.

  3. The anterior tilt angle of the proximal tibia epiphyseal plate: A significant radiological finding in young children with trampoline fractures

    International Nuclear Information System (INIS)

    Stranzinger, Enno; Leidolt, Lars; Eich, Georg; Klimek, Peter Michael

    2014-01-01

    Objective: Evaluation of the anterior tilt angle of the proximal tibia epiphyseal plate in young children, which suffered a trampoline fracture in comparison with a normal population. Materials and methods: 62 children (31 females, 31 males) between 2 and 5 years of age (average 2 years 11 months, standard deviation 11 months) with radiographs in two views of the tibia were included in this retrospective study. 25 children with proximal tibia fractures were injured with a history of jumping on a trampoline. All other causes for tibia fractures were excluded. A normal age-mapped control cohort of 37 children was compared. These children had neither evidence of a trampoline related injury nor a fracture of the tibia. The anterior tilt angle of the epiphyseal plate of the tibia was defined as an angle between the proximal tibia physis and the distal tibia physis on a lateral view. Two radiologists evaluated all radiographs for fractures and measured the anterior tilt angle in consensus. An unpaired Student's t-test was used for statistical analysis (SPSS). Original reports were reviewed and compared with the radiological findings and follow-up radiographs. Results: In the normal control group, the average anterior tilt angle measured −3.2°, SD ± 2.8°. The children with trampoline fractures showed an anterior tilt of +4.4°, SD ± 2.9°. The difference was statistically significant, P < 0.0001. In 6 patients (24% of all patients with confirmed fractures) the original report missed to diagnose the proximal tibial fracture. Conclusion: Young children between 2 and 5 years of age are at risk for proximal tibia fractures while jumping on a trampoline. These fractures may be very subtle and difficult to detect on initial radiographs. Measurement of the anterior tilt angle of the proximal tibia epiphyseal plate on lateral radiographs is supportive for interpreting correctly trampoline fractures

  4. The anterior tilt angle of the proximal tibia epiphyseal plate: A significant radiological finding in young children with trampoline fractures

    Energy Technology Data Exchange (ETDEWEB)

    Stranzinger, Enno, E-mail: enno.stranzinger@insel.ch [University Hospital Bern, Inselspital, Department of Diagnostic, Interventional and Pediatric Radiology, CH-3010 Bern (Switzerland); Leidolt, Lars, E-mail: lars.leidolt@insel.ch [University Hospital Bern, Inselspital, Department of Diagnostic, Interventional and Pediatric Radiology, CH-3010 Bern (Switzerland); Eich, Georg, E-mail: georg.eich@ksa.ch [Cantonal Hospital Aarau, Pediatric Radiology, Tellstrasse, CH-5001 Aarau (Switzerland); Klimek, Peter Michael, E-mail: peter.klimek@ksa.ch [Cantonal Hospital Aarau, Pediatric Surgery, Tellstrasse, CH-5001 Aarau (Switzerland)

    2014-08-15

    Objective: Evaluation of the anterior tilt angle of the proximal tibia epiphyseal plate in young children, which suffered a trampoline fracture in comparison with a normal population. Materials and methods: 62 children (31 females, 31 males) between 2 and 5 years of age (average 2 years 11 months, standard deviation 11 months) with radiographs in two views of the tibia were included in this retrospective study. 25 children with proximal tibia fractures were injured with a history of jumping on a trampoline. All other causes for tibia fractures were excluded. A normal age-mapped control cohort of 37 children was compared. These children had neither evidence of a trampoline related injury nor a fracture of the tibia. The anterior tilt angle of the epiphyseal plate of the tibia was defined as an angle between the proximal tibia physis and the distal tibia physis on a lateral view. Two radiologists evaluated all radiographs for fractures and measured the anterior tilt angle in consensus. An unpaired Student's t-test was used for statistical analysis (SPSS). Original reports were reviewed and compared with the radiological findings and follow-up radiographs. Results: In the normal control group, the average anterior tilt angle measured −3.2°, SD ± 2.8°. The children with trampoline fractures showed an anterior tilt of +4.4°, SD ± 2.9°. The difference was statistically significant, P < 0.0001. In 6 patients (24% of all patients with confirmed fractures) the original report missed to diagnose the proximal tibial fracture. Conclusion: Young children between 2 and 5 years of age are at risk for proximal tibia fractures while jumping on a trampoline. These fractures may be very subtle and difficult to detect on initial radiographs. Measurement of the anterior tilt angle of the proximal tibia epiphyseal plate on lateral radiographs is supportive for interpreting correctly trampoline fractures.

  5. In-situ mechanical behavior and slackness of the anterior cruciate ligament at multiple knee flexion angles

    NARCIS (Netherlands)

    Rachmatt, H.H.; Janssen, D.; Verkerke, Gijsbertus Jacob; Diercks, R.L.; Verdonschot, Nicolaas Jacobus Joseph

    2015-01-01

    In this study the in-situ tensile behavior and slackness of the anterior cruciate ligament (ACL) was evaluated at various knee flexion angles. In four cadaveric knees the ACL was released at the tibial insertion, after which it was re-connected to a tensiometer. After pre-tensioning (10 N) the ACL

  6. In-situ mechanical behavior and slackness of the anterior cruciate ligament at multiple knee flexion angles

    NARCIS (Netherlands)

    Rachmat, H.H.; Janssen, D.W.; Verkerke, G.J.; Diercks, R.L.; Verdonschot, N.J.J.

    2016-01-01

    In this study the in-situ tensile behavior and slackness of the anterior cruciate ligament (ACL) was evaluated at various knee flexion angles. In four cadaveric knees the ACL was released at the tibial insertion, after which it was re-connected to a tensiometer. After pre-tensioning (10 N) the ACL

  7. In-situ mechanical behavior and slackness of the anterior cruciate ligament at multiple knee flexion angles

    NARCIS (Netherlands)

    Rachmat, Hendi; Janssen, D.; Verkerke, Gijsbertus; Diercks, Ronald; Verdonschot, N.

    In this study the in-situ tensile behavior and slackness of the anterior cruciate ligament (ACL) was evaluated at various knee flexion angles. In four cadaveric knees the ACL was released at the tibial insertion, after which it was re-connected to a tensiometer. After pre-tensioning (10 N) the ACL

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

    Science.gov (United States)

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

    2010-01-01

    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. IOP, basal tear secretion (BTS), reflex tear secretion (RTS), and Pentacam measurements of 31 healthy volunteers were performed at 0800 and 1600 hours during Ramadan fasting and 1 month later during non-fasting period. Comparison of measurements between fasting and non-fasting periods at 0800 hours revealed significantly higher values for IOP (P=0.005), RTS (P=0.006), and BTS (P=0.014) during fasting. Conversely at 1600 hours, IOP was significantly lower during fasting (P=0.013) and no statistically significant difference was noted for RTS and BTS. IOP showed a diurnal variation of 2.45 mmHg (P<0.001) and BTS showed a 3.06 mm decrease (P=0.04) during the fasting period. No significant differences could be found in the corneal and anterior chamber parameters during fasting and non-fasting periods. Our results revealed that fluid loading at the pre-dawn meal during Ramadan fasting might increase the IOP and tear secretion in the early morning period and these values decrease remarkably at the end of 12 h of fasting due to dehydration.

  9. Electromechanical artificial heart with a new gear type and angled pump chambers.

    Science.gov (United States)

    Kaufmann, R; Reul, H; Rau, G

    1992-08-01

    The intrathoracic anatomical situation after explantation of the natural heart defines the maximum available space for the design of the housing as well as of the inlet- and outlet connectors of a fully implantable electromechanical artificial heart. Based on computer-assisted anatomical studies, a total artificial heart housing is designed which facilitates an oblique orientation of the pumping chambers for a better fluidmechanical and anatomical arrangement of the in- and outlet connectors. The pumping chamber geometry is based on modifications of an existing cardiac assist-system. Subsequently a mechanical gear which conforms to this anatomically adapted housing is developed.

  10. open angle glaucoma (poag)?

    African Journals Online (AJOL)

    there is a build up of pressure due to poor outflow of aqueous humor. The outflow obstruction could occur at the trabecular meshwork of the anterior chamber angle or subsequently in the episcleral vein due to raised venous pressure. Such build up of pressure results in glaucoma . Elevated intraocular pressure remains the ...

  11. Significant relationship between local angle at fused segments and C2-7 angle: Average duration of longer than 20 years after anterior cervical discectomy and fusion

    Directory of Open Access Journals (Sweden)

    T Nagata

    2011-01-01

    Full Text Available Background : The authors have focused their attention to the radiological durability of cervical sagittal alignment after anterior cervical discectomy and fusion (ACDF using autologous bone grafting. Materials and Methods : Among the patients who underwent ACDF with trans-unco-discal (TUD approach between 1976 and 1997, 22 patients (16 males and 6 females made return visits for a clinical evaluation. Patients with trauma or previously treated by anterior cervical fusion or by posterior decompression were excluded from the present study. Clinical evaluation included adjacent segment degeneration (ASD, osseous fusion, local angle at the fused segments and C2-7 angle of cervical spine. Results : The duration after ACDF ranged from 13 to 34 years with an average of 21.3 ± 7.0 years. A single level fusion was done on 8 patients, 2 levels on 11 patients, 3 levels on 2 patients, and 4 levels on 1 patient. Imaging studies indicated that 12 of the 22 patients (54.5% were graded as having symptomatic ASD. Osseous bony fusion at ACDF was recognized in all cases. None of the patients demonstrated kyphotic malalignment of the cervical spine. Average degrees of local angle at the fused segments and the C2-7 angle were 7.06 and 17.6, respectively. Statistical analysis indicated a significant relationship between the local at the fused segments and C2-7 angles. Conclusions : Sagittal alignment of the cervical spine was durable long after ACDF when the local angle at the fused segments was well stabilized.

  12. Comparison between a New Optical Biometry Device and an Anterior Segment Optical Coherence Tomographer for Measuring Central Corneal Thickness and Anterior Chamber Depth

    Directory of Open Access Journals (Sweden)

    Jinhai Huang

    2016-01-01

    Full Text Available Purpose. To compare between a new optical biometer (AL-Scan, Nidek Co., Aichi, Japan and an anterior segment optical coherence tomographer (Visante AS-OCT, Carl Zeiss Meditec, Dublin, USA for measuring central corneal thickness (CCT, anterior chamber depth (ACD, and aqueous depth (AD. Methods. Sixty-three eyes of 63 normal subjects were examined with AL-Scan and Visante AS-OCT in this prospective study. One eye per subject was measured three times with both devices to record their CCT, ACD, and AD. All procedures were performed by the same operator. Agreement between the two devices was assessed using paired t-tests, Bland-Altman plots, and 95% limits of agreement (LoA. Results. The mean CCT, ACD, and AD measured by AL-Scan were 538.59±27.37 μm, 3.70±0.30 mm, and 3.16±0.30 mm, respectively. The mean values obtained by the Visante OCT were 536.14±26.61 μm for CCT, 3.71±0.29 mm for ACD, and 3.17±0.29 mm for AD. The mean CCT by the AL-Scan was higher than that obtained by the Visante AS-OCT (difference = 2.45±6.07 μm, P<0.05. The differences in ACD and AD measurements were not statistically significant. The 95% LoA of CCT, ACD, and AD were between −9.44 and 14.35 μm, −0.15 and 0.12 mm, and −0.15 and 0.12 mm, respectively. Conclusions. Since these two devices were comparable for measuring CCT, ACD, and AD, their results can be interchangeably used in the clinic.

  13. Distribution of axial length, anterior chamber depth, and corneal curvature in an aged population in South China.

    Science.gov (United States)

    Chen, Hui; Lin, Haotian; Lin, Zhuoling; Chen, Jingjing; Chen, Weirong

    2016-05-01

    Ocular biometry is important for preoperative assessment in cataract and anterior segment surgery. The purpose of this study was to investigate normative ocular biometric parameters and their associations in an older Chinese population. This was a cross-sectional observational study. From 2013 to 2014, we recruited inhabitants aged 50 years or older in Guangzhou, China. Among 1,117 participants in the study, data from 1,015 phakic right eyes were used for analyses. Ocular parameters including axial length (AL), anterior chamber depth (ACD), and corneal curvature (K) were measured using an IOL Master. The mean AL, ACD, and K were 23.48 mm [95 % confidence interval (CI), 23.40-23.55], 3.03 mm (CI, 3.01-3.05), and 44.20 mm (CI, 44.11-44.29), respectively. A mean reduction in ACD with age was observed (P = 0.002) in male subjects but not in female subjects (P = 0.558). Male subjects had significantly longer ALs (23.68 mm versus 23.23 mm, P population in South China. The AL in this Chinese cohort was greater than that observed in the Singaporean Chinese but smaller than that observed in Malaysia and for Caucasians. The Chinese have a shallower ACD than some other racial groups. Age and sex were the most consistent predictors of ocular biometry in the older population from South China.

  14. Changes in Anterior Chamber Depth after Phacoemulsification in Pseudoexfoliative Eyes and their Effect on Accuracy of Intraocular Lens Power Calculation

    Directory of Open Access Journals (Sweden)

    Sirel Gür Güngör

    2016-12-01

    Full Text Available Objectives: To compare anterior chamber depth (ACD changes after phacoemulsification surgery in patients with pseudoexfoliation syndrome (PEX and normal patients using an anterior segment imaging method. Another aim of this study was to evaluate the effect of these changes on the accuracy of intraocular lens (IOL power calculation and postoperative refraction. Materials and Methods: Twenty-two eyes of 22 patients with PEX and 30 eyes of 30 normal patients who underwent uneventful phacoemulsification surgery and IOL implantation were included in the study. The ACD of all patients was evaluated preoperatively and at 3 months postoperatively with the ALLEGRO Oculyzer (WaveLight® Oculyzer™ II, Alcon, Novartis-Scheimpflug imaging system. Results: The postoperative mean ACD values were significantly larger than the preoperative ACD values in both groups (p<0.001 for both groups. The pre- to postoperative change in ACD was 0.46±0.3 mm in the PEX group, which was a larger change than seen in the normal patients (0.12±0.1 mm (p=0.04. The mean absolute errors (MAE calculated with different IOL formulas (SRK/T, Haigis, Hoffer and Holladay 1 formulas were comparable and no statistically significant difference was observed between the two groups (p=0.21. Conclusion: Phacoemulsification induces more significant ACD changes in patients with PEX compared to normal patients. However, the MAE did not differ significantly between the groups.

  15. Changes in Anterior Chamber Depth after Phacoemulsification in Pseudoexfoliative Eyes and their Effect on Accuracy of Intraocular Lens Power Calculation

    Science.gov (United States)

    Gür Güngör, Sirel; Akman, Ahmet; Asena, Leyla; Aksoy, Mustafa; Sarıgül Sezenöz, Almila

    2016-01-01

    Objectives: To compare anterior chamber depth (ACD) changes after phacoemulsification surgery in patients with pseudoexfoliation syndrome (PEX) and normal patients using an anterior segment imaging method. Another aim of this study was to evaluate the effect of these changes on the accuracy of intraocular lens (IOL) power calculation and postoperative refraction. Materials and Methods: Twenty-two eyes of 22 patients with PEX and 30 eyes of 30 normal patients who underwent uneventful phacoemulsification surgery and IOL implantation were included in the study. The ACD of all patients was evaluated preoperatively and at 3 months postoperatively with the ALLEGRO Oculyzer (WaveLight® Oculyzer™ II, Alcon, Novartis)-Scheimpflug imaging system. Results: The postoperative mean ACD values were significantly larger than the preoperative ACD values in both groups (p<0.001 for both groups). The pre- to postoperative change in ACD was 0.46±0.3 mm in the PEX group, which was a larger change than seen in the normal patients (0.12±0.1 mm) (p=0.04). The mean absolute errors (MAE) calculated with different IOL formulas (SRK/T, Haigis, Hoffer and Holladay 1 formulas) were comparable and no statistically significant difference was observed between the two groups (p=0.21). Conclusion: Phacoemulsification induces more significant ACD changes in patients with PEX compared to normal patients. However, the MAE did not differ significantly between the groups. PMID:28050320

  16. Second-Trimester Anterior Cervical Angle in a Low-Risk Population as a Marker for Spontaneous Preterm Delivery.

    Science.gov (United States)

    Sepúlveda-Martínez, Alvaro; Díaz, Francisco; Muñoz, Hernán; Valdés, Enrique; Parra-Cordero, Mauro

    2017-01-01

    The aim of this article is to assess the use of the anterior cervical angle (ACA) as a predictor of spontaneous preterm delivery (sPTD) at 20+0-24+6 weeks of gestation in an unselected population. We conducted a nested case-control study that included 93 women who later delivered spontaneously history, CL and ACA at 20+0-24+6 weeks of gestation can predict approximately 40% of the severe preterm births. © 2016 S. Karger AG, Basel.

  17. Comparison of central corneal thickness and anterior chamber depth measurements using three imaging technologies in normal eyes and after phakic intraocular lens implantation.

    NARCIS (Netherlands)

    Doors, M.; Cruysberg, L.P.J.; Berendschot, T.T.; Brabander, J. De; Verbakel, F.; Webers, C.A.; Nuijts, R.M.

    2009-01-01

    BACKGROUND: The repeatability and interchangeability of imaging devices measuring central corneal thickness (CCT) and anterior chamber depth (ACD) are important in the assessment of patients considering refractive surgery. The purpose of this study was to investigate the agreement of CCT and ACD

  18. The Injection of Air/Oxygen Bubble into the Anterior Chamber of Rabbits as a Treatment for Hyphema in Patients with Sickle Cell Disease

    Directory of Open Access Journals (Sweden)

    Emre Ayintap

    2014-01-01

    Full Text Available Purpose. To investigate the changes of partial oxygen pressure (PaO2 in aqueous humour after injecting air or oxygen bubble into the anterior chamber in sickle cell hyphema. Methods. Blood samples were taken from the same patient with sickle cell disease. Thirty-two rabbits were divided into 4 groups. In group 1 (n=8, there was no injection. Only blood injection constituted group 2 (n=8, both blood and air bubble injection constituted group 3 (n=8, and both blood and oxygen bubble injection constituted group 4 (n=8. Results. The PaO2 in the aqueous humour after 10 hours from the injections was 78.45 ± 9.9 mmHg (Mean ± SD for group 1, 73.97 ± 8.86 mmHg for group 2, 123.35 ± 13.6 mmHg for group 3, and 306.47 ± 16.5 mmHg for group 4. There was statistically significant difference between group 1 and group 2, when compared with group 3 and group 4. Conclusions. PaO2 in aqueous humour was increased after injecting air or oxygen bubble into the anterior chamber. We offer to leave an air bubble in the anterior chamber of patients with sickle cell hemoglobinopathies and hyphema undergoing an anterior chamber washout.

  19. Splenic CD8(+) T cells secrete TGF-beta 1 to exert suppression in mice with anterior chamber-associated immune deviation

    NARCIS (Netherlands)

    Jiang, L.Q.; He, H.; Yang, P.Z.; Lin, X.M.; Zhou, H.Y.; Huang, X.K.; Kijlstra, A.

    2009-01-01

    Background CD8(+) regulatory T cells (Treg) have been considered to be involved in a model of ocular-induced tolerance, known as anterior chamber-associated immune deviation (ACAID). The mechanisms of suppression by CD8(+) T cells in ACAID remain only poorly understood. TGF-beta 1 is considered as

  20. Dynamic changes of anterior segment in patients with different stages of primary angle-closure in both eyes and normal subjects.

    Directory of Open Access Journals (Sweden)

    Jialiu Lin

    Full Text Available To compare changes in anterior segment parameters under light and dark (light-to-dark conditions among eyes with chronic primary angle-closure glaucoma (CPACG, fellow eyes with confirmed or suspect primary angle-closure (PAC or PACS, and age-matched healthy eyes.Consecutive patients with CPACG in one eye and PAC/PACS in the fellow eye, as well as age-matched healthy subjects were recruited. Anterior segment optical coherence tomography measurements were conducted under light and dark conditions, and anterior chamber, lens, and iris parameters compared. Demographic and biometric factors associated with light-to-dark change in iris area were analyzed by linear regression.Fifty-seven patients (mean age 59.6±8.9 years and 30 normal subjects matched for age (60.6±9.3 years and sex ratio were recruited. In regards to differences under light-to-dark conditions, angle opening distance at 500 μm (AOD500μm and iris area during light-to-dark transition were smaller in CPACG eyes than fellow PACS/PAC eyes and normal eyes (P<0.017. Pupil diameter change was largest in normal eyes, and larger in PACS/PAC eyes than CPACG eyes (P<0.017. There was an average reduction of 0.145 mm2 in iris area for each millimeter of pupil diameter increase in CPACG eyes, 0.161 mm2 in fellow PAC/PACS eyes, and 0.165 mm2 in normal eyes. Larger iris curvature in the dark and diagnosis of PACG were significantly associated with less light-to-dark iris area changes.Dynamic changes in iris parameters with light-to-dark transition differed significantly among CPACG eyes, fellow PAC/PACS eyes, and normal eyes. Greater iris curvature under dark conditions was correlated with reduced light-to-dark change in iris area and pupil diameter, which may contribute to disease progression.

  1. An ultra-high vacuum chamber for scattering experiments featuring in-vacuum continuous in-plane variation of the angle between entrance and exit vacuum ports.

    Science.gov (United States)

    Englund, Carl-Johan; Agåker, Marcus; Fredriksson, Pierre; Olsson, Anders; Johansson, Niklas; Rubensson, Jan-Erik; Nordgren, Joseph

    2015-09-01

    A concept that enables in-vacuum continuous variation of the angle between two ports in one plane has been developed and implemented. The vacuum chamber allows for measuring scattering cross sections as a function of scattering angle and is intended for resonant inelastic X-ray scattering experiments. The angle between the ports can be varied in the range of 30°-150°, while the pressure change is less than 2 × 10(-10) mbars.

  2. Do peak torque angles of muscles change following anterior cruciate ligament reconstruction using hamstring or patellar tendon graft?

    Science.gov (United States)

    Yosmaoğlu, Hayri Baran; Baltacı, Gül; Sönmezer, Emel; Özer, Hamza; Doğan, Deha

    2017-12-01

    This study aims to compare the effects of anterior cruciate ligament (ACL) reconstruction using autogenous hamstring or patellar tendon graft on the peak torque angle. The study included 132 patients (103 males, 29 females; mean age 29±9 year) who were performed ACL reconstruction with autogenous hamstring or patellar tendon graft. The peak torque angles in the quadriceps and hamstring muscles were recorded using an isokinetic dynamometer. Angle of peak knee flexion torque occurred significantly earlier within the range of motion on the operated side than nonoperated side at 180°/second in the hamstring tendon group. Angle of peak knee extension torque occurred significantly earlier within the range of motion on the operated side than nonoperated side at 180°/second in the patellar tendon group. There were no statistically significant differences in the flexion and extension peak torque angles between the operated and nonoperated knees at 60°/second in both groups. The angle of peak torque at relatively high angular velocities is affected after ACL reconstruction in patients with hamstring or patellar tendon grafts. The graft donor site directly influences this parameter. This finding may be important for clinicians in terms of preventing re-injury.

  3. Comparison of reaction forces on the anterior cruciate and anterolateral ligaments during internal rotation and anterior drawer forces at different flexion angles of the knee joint.

    Science.gov (United States)

    Uğur, Levent

    2017-12-01

    Having a complicated anatomy, the knee joint has been further detailed and a new formation defined, the anterolateral ligament (ALL), in recent studies. While the importance of this ligament, which previously was associated with Segond fractures, was explained via clinical, radiologic and biomechanical studies, and basically, is thought to be a fixator structures for the tibia against internal rotation stress. Although in recent studies efficient surgical treatment was applied to patients who underwent anterior cruciate ligament (ACL) operation, some patients having a positive pivot test highlights the clinical importance of the ALL. The aim of this study is to evaluate reaction forces of different flexion angles on the tibia during internal rotation and anterior drawer tests on both the ALL and ACL, and to examine theimportance of this ligament in knee biomechanics by a finite element analysis method. In this study, normal anatomy knee joint was modelled using Computed Tomography images from lower extremity length in DICOM format. 0°, 15°,30°,45°,60°,75° and 90° angles of flexion were applied, respectively, to these models and reaction force vectors formed on both ligaments were examined separately and as total vector and size by applying internal rotation and anterior drawer forces on each model. Non-linear analysis was conducted using ANSYS (version 17) with the same limit conditions applied to all models. After all models were examined, in general when comparing reaction forces, those on the ACL were found to be higher. However, when vectoral directions were examined, forces on ALL increased with increased flexion ratio and internal rotation momentum. Beyond 30° flexion, the tensile force on the ALL is increased and compressive overload on the ACL occurs. The ALL plays an important role in stability, especially against internal rotation forces, and an increased knee joint flexion ratio increases the stability contribution ratio. In particular, at 30

  4. The impact of insonation angle on four-chamber view image quality: an observational study on 2866 routine scans.

    Science.gov (United States)

    Jaudi, Suha; Fries, Nicolas; Tezenas du Montcel, Sophie; Dommergues, Marc

    2015-04-01

    To determine insonation angles achieved in routine screening practice and their impact on image quality. Prospective cross-sectional observational survey of 2866 four-chamber views produced by 287 senor ultrasonographers, from unselected routine second-trimester screening scans. Images were scored from 0 to 5 according to whether two atria, two ventricles, the heart crux, the apex, and the descending aorta were seen. Images were considered adequate if two atria, two ventricles, and the heart crux were seen. The insonation angle was classified as apical, basal, or lateral according to the orientation of the fetal heart to the ultrasound beam. There were 1612 (56.3%) apical, 869 (30.3%) basal, and 385 (13.4%) lateral views. The mean score and the rate of adequate images were significantly greater in the apical group (4.56 and 81.8%) than in the basal group (4.19 and 71.1 %) and were significantly greater in the basal group than in the lateral one (3.6 and 30.9%), p John Wiley & Sons, Ltd. © 2015 John Wiley & Sons, Ltd.

  5. A Further Finite Element Stress Analysis of Angled Abutments for an Implant Placed in the Anterior Maxilla

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    Dong Wu

    2015-01-01

    Full Text Available To systematically measure and compare the stress distribution on the bone around an implant in the anterior maxilla using angled abutments by means of finite element analysis, three-dimensional finite element simplified patient-specific models and simplified models were created and analyzed. Systematically varied angled abutments were simulated, with angulation ranging from 0° to 60°. The materials in the current study were assumed to be homogenous, linearly elastic, and isotropic. Force of 100 N was applied to the central node on the top surface of the abutments to simulate the occlusal force. To simulate axial and oblique loading, the angle of loading was 0°, 15°, and 20° to the long axis of implant, respectively. There was the strong resemblance between the response curves for simplified patient-specific models and simplified models. Response curves under oblique loading were similar in both models. With abutments angulation increased, maximum von Mises stress firstly decreased to minimum point and then gradually increased to higher level. From a biomechanical point of view, favorable peri-implant stress levels could be induced by angled abutments under oblique loading if suitable angulation of abutments was selected.

  6. Dynamic analysis of iris configuration with anterior segment optical coherence tomography.

    Science.gov (United States)

    Cheung, Carol Yim-lui; Liu, Shu; Weinreb, Robert N; Liu, Jing; Li, Haitao; Leung, Dexter Yu-lung; Dorairaj, Syril; Liebmann, Jeffrey; Ritch, Robert; Lam, Dennis Shun Chiu; Leung, Christopher Kai-shun

    2010-08-01

    To evaluate dynamic changes in iris configuration and their association with anterior chamber angle width by using anterior segment optical coherence tomography (ASOCT). Forty-six normal subjects with open angles and 40 with narrow angles (Shaffer grade dark room gonioscopy) were analyzed. The dynamic ASOCT dark-light changes of iris bowing were captured with real-time video recording and nasal iris bowing, nasal anterior chamber angle, and pupil diameter were measured in serial image frames selected from the video capture. The associations between iris bowing, iris thickness, anterior chamber depth (ACD), age, anterior chamber angle, and pupillary diameter measurements were evaluated with univariate and multivariate regression analyses. The relationship between iris bowing and pupil diameter was largely linear, with three dynamic patterns observed: (1) convex-to-convex (iris remains convex in dark and light); (2) concave-to-convex (iris changes from concave to convex from light to dark); and (3) concave-to-concave (iris remains concave in dark and light). All the subjects with narrow angles had convex-to-convex anatomy, although 43% of the subjects with open angles also demonstrated this pattern. These individuals were older and had shorter axial length (both with P dark (r = 0.472, P dark. ACD and iris bowing were independently associated with anterior chamber angle width. Independent of ACD, iris bowing is an important biometric parameter that determines angle width. Investigation of iris dynamics may offer a new perspective in understanding the risk and mechanism of primary angle closure.

  7. Modification of Knee Flexion Angle Has Patient-Specific Effects on Anterior Cruciate Ligament Injury Risk Factors During Jump Landing.

    Science.gov (United States)

    Favre, Julien; Clancy, Caitlin; Dowling, Ariel V; Andriacchi, Thomas P

    2016-06-01

    The incidence of anterior cruciate ligament (ACL) injuries may be decreased through the use of intervention programs that focus on increasing the knee flexion angle during jump landing, which decreases strain on the ACL. To investigate whether intervention training designed to change the knee flexion angle during landing causes secondary changes in other known measures associated with the risk of ACL injuries and to examine the time points when these secondary measures change. Controlled laboratory study. A total of 39 healthy recreational athletes performed a volleyball block jump task in an instrumented gait laboratory. The participants first completed the jumps without any modification to their normal landing technique. They were then given oral instruction to land softly and to increase their knee flexion angle during landing. Lower body kinematics and kinetics were measured before and after the modification using an optoelectronic motion capture system. The knee flexion angle after the modification significantly increased from 11.2° to 15.2° at initial contact and from 67.8° to 100.7° at maximum flexion, and the time between initial contact and maximum flexion increased from 177.4 to 399.4 milliseconds. The flexion modification produced a substantial reduction in vertical ground-reaction force (243.1 to 187.8 %BW) with a concomitant reduction in the maximum flexion moment. Interestingly, the flexion modification only affected the abduction angle and abduction moment for the group of participants that landed in an initial adducted position before the modification and had no significant effect on the group that landed in an abducted position. Increasing the knee flexion angle during jump landing may be an effective intervention to improve knee biomechanical risk factors associated with an ACL injury. However, the fact that the flexion modification only influenced critical risk factors (the abduction angle and abduction moment) in participants who initially

  8. Non-arteritic anterior ischemic optic neuropathy secondary to acute primary-angle closure

    Directory of Open Access Journals (Sweden)

    Kuriyan AE

    2013-07-01

    Full Text Available Ajay E Kuriyan, Byron L Lam Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA Purpose: To describe a case of non-arteritic ischemic optic neuropathy (NAION secondary to acute primary-angle closure (APAC. Methods: Case report. Results: A 50-year-old woman with painful visual loss in the right eye was found to be in APAC with a right afferent pupillary defect. Laser peripheral iridotomy relieved pain but did not improve vision. Diffuse optic disc edema in the right eye and a small cup-to-disc ratio in the left eye were evident. Magnetic resonance imaging was normal. The patient was diagnosed with non-arteritic ischemic optic neuropathy (NAION secondary to APAC, a rare clinical entity which can result in markedly decreased visual acuity. Conclusion: NAION secondary to APAC is a rare clinical entity that can result in severe vision loss. Keywords: acute angle closure glaucoma, perfusion pressure, NAION, optic nerve

  9. Trabeculectomy combined with deep sclerectomy and scleral flap suture tension adjustment under an anterior chamber maintainer: a new modification of trabeculectomy.

    Science.gov (United States)

    Kayikcioglu, Ozcan R; Emre, Sinan; Kaya, Ziya

    2010-06-01

    The objective of this study was to investigate the efficacy and safety of trabeculectomy combined with deep sclerectomy in patients with primary open angled glaucoma (POAG) and to compare the results with those from conventional trabeculectomy. In the study 12 eyes of 10 patients operated with trabeculectomy combined with deep sclerectomy (Group I) and 16 eyes of 16 patients operated with conventional trabeculectomy surgery (Group II) were included. In the described form of combined deep sclerectomy with the trabeculectomy technique the superficial scleral flap was sutured with 10/0 monofilament, the number and tension of sutures were adjusted according to the outflow dynamics, under the scleral flap, of balanced salt solution (BSS) provided by an anterior chamber maintainer. In groups I and II all the patients were male POAG cases with mean ages of 60.0 +/- 19.4 and 67.0 +/- 7.1 years, respectively. The mean follow-up periods were 8.3 +/- 3.5 months for group I and 16.6 +/- 7.0 months for group II. Preoperative mean IOP were 29.7 +/- 8.3 and 29.1 +/- 12.8 mmHg mmHg, and average topical antiglaucomatous medications were 2.9 +/- 0.7 and 2.7 +/- 1.1 for groups I and II, respectively. Postoperatively mean IOP measurements were reduced in groups I and II to 10.5 +/- 2.9 vs. 9.6 +/- 4.8 mmHg at 1 week, 13.7 +/- 5.6 vs. 16.0 +/- 9.8 at 1st month, 12.3 +/- 6.4 vs. 17.3 +/- 8.0 at 3rd month, 11.0 +/- 4.1 vs. 15.3 +/- 5.8 at 6th month, 10.8 +/- 1.6 vs. 16.1 +/- 4.4 at 12th month, and 11.0 +/- 1.0 vs. 16.7 +/- 5.0 at 18th month. Statistical analysis revealed that mean postoperative IOP measurements for group I were significantly lower than for group II for all measurements except the first week (P < 0.05). At 12th month, the complete (IOP <22 mmHg without medication) and qualified (IOP <22 mmHg with medication) success rates were 83.3 and 100% for group I and 63.6 and 90.9% for group II. Postoperatively at 12th month, the mean number of antiglaucoma medications had fallen to

  10. Má oclusão Classe I de Angle, com mordida aberta anterior, tratada com extração de dentes permanentes Angle Class I malocclusion, with anterior open bite, treated with extraction of permanent teeth

    Directory of Open Access Journals (Sweden)

    Mírian Aiko Nakane Matsumoto

    2011-02-01

    Full Text Available A mordida aberta é uma anomalia com características distintas que, além da complexidade dos múltiplos fatores etiológicos, traz consequências estéticas e funcionais. Muitas alternativas têm sido utilizadas em seu tratamento, entre elas a grade palatina, forças ortopédicas, ajuste oclusal, camuflagem com ou sem exodontias, mini-implantes ou miniplacas e cirurgia ortognática. O diagnóstico preciso e a determinação da etiologia permitem estabelecer os objetivos e o plano de tratamento ideal para essa má oclusão. O presente relato descreve o tratamento de uma má oclusão Classe I de Angle, com padrão esquelético de Classe II e mordida aberta anterior, realizado em duas fases e que foi apresentado à diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO, representando a categoria 2, como parte dos requisitos para a obtenção do título de Diplomado pelo BBO.Open bite is an anomaly with distinct characteristics which, in addition to involving complex, multiple etiologic factors, entails aesthetic and functional consequences. Many alternative approaches have been employed to treat open bite, including palatal crib, orthopedic forces, occlusal adjustment, camouflage with or without extractions, mini-implants or mini-plates, and orthognathic surgery. By determining accurate diagnosis and etiology professionals can set the goals and ideal treatment plan for this malocclusion. This report, describing the two stages treatment of a Angle Class I malocclusion with Class II skeletal pattern and anterior open bite, was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO, representative of category 2, as partial fulfillment of the requirements for obtaining the title of BBO Diplomate.

  11. Isometric hip abduction using a Thera-Band alters gluteus maximus muscle activity and the anterior pelvic tilt angle during bridging exercise.

    Science.gov (United States)

    Choi, Sil-Ah; Cynn, Heon-Seock; Yi, Chung-Hwi; Kwon, Oh-Yun; Yoon, Tae-Lim; Choi, Woo-Jeong; Lee, Ji-Hyun

    2015-04-01

    The purpose of this study was to investigate the effects of bridging with isometric hip abduction (IHA) using the Thera-Band on gluteus maximus (GM), hamstring (HAM), and erector spinae (ES) muscle activity; GM/HAM and GM/ES ratios; and the anterior pelvic tilt angle in healthy subjects. Twenty-one subjects participated in this study. Surface EMG was used to collect EMG data of GM, HAM, and ES muscle activities, and Image J software was used to measure anterior pelvic tilt angle. A paired t-test was used to compare GM, HAM, and ES muscle activity; the GM/HAM and GM/ES ratios; and the anterior pelvic tilt angle with and without IHA during the bridging exercise. GM muscle activity increased significantly and the anterior pelvic tilt angle decreased significantly during bridging with IHA using the Thera-Band (p 0.05). The results of this study suggest that bridging with IHA using the Thera-Band can be implemented as an effective method to facilitate GM muscle activity and reduce the anterior pelvic tilt angle. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Isokinetic angle-specific moments and ratios characterizing hamstring and quadriceps strength in anterior cruciate ligament deficient knees.

    Science.gov (United States)

    Huang, Hongshi; Guo, Jianqiao; Yang, Jie; Jiang, Yanfang; Yu, Yuanyuan; Müller, Steffen; Ren, Gexue; Ao, Yingfang

    2017-08-04

    This study is intended to find more effective and robust clinical diagnostic indices to characterize muscle strength and coordination alternation following anterior cruciate ligament (ACL) rupture. To evaluate angle-specific moments and hamstring (H)/quadriceps (Q) ratios, 46 male subjects with unilateral chronic ACL-rupture performed isokinetic concentric (c), eccentric (e) quadriceps and hamstring muscle tests respectively at 60°/s. Normalized moments and H/Q ratios were calculated for peak moment (PM) and 30°, 40°, 50°, 60°, 70°, 80° knee flexion angles. Furthermore, we introduced single-to-arithmetic-mean (SAM) and single-to-root-mean-square (SRMS) muscle co-contraction ratios, calculating them for specific angles and different contraction repetitions. Normalized PM and 40° specific concentric quadriceps, concentric hamstring strength in the ACL-deficient knee were reduced significantly (P ≤ 0.05). Concentric angle-specific moments together with Qe/Qc ratios at 40° (d = 0.766 vs. d = 0.654) identify more obvious differences than peak values in ACL ruptured limbs. Furthermore, we found SRMS-QeQc deficits at 40° showed stronger effect than Qe/Qc ratios (d = 0.918 vs. d = 0.766), albeit other ratio differences remained basically the same effect size as the original H/Q ratios. All the newly defined SAM and SRMS indices could decrease variance. Overall, 40° knee moments and SAM/SRMS ratios might be new potential diagnosis indices for ACL rupture detection.

  13. Non-arteritic anterior ischemic optic neuropathy secondary to acute primary-angle closure.

    Science.gov (United States)

    Kuriyan, Ajay E; Lam, Byron L

    2013-01-01

    To describe a case of non-arteritic ischemic optic neuropathy (NAION) secondary to acute primary-angle closure (APAC). Case report. A 50-year-old woman with painful visual loss in the right eye was found to be in APAC with a right afferent pupillary defect. Laser peripheral iridotomy relieved pain but did not improve vision. Diffuse optic disc edema in the right eye and a small cup-to-disc ratio in the left eye were evident. Magnetic resonance imaging was normal. The patient was diagnosed with non-arteritic ischemic optic neuropathy (NAION) secondary to APAC, a rare clinical entity which can result in markedly decreased visual acuity. NAION secondary to APAC is a rare clinical entity that can result in severe vision loss.

  14. Ultrasound biomicroscopy of the anterior segment.

    Science.gov (United States)

    Liebmann, J M; Ritch, R

    1996-08-01

    New imaging technologies are revolutionizing the understanding and treatment of a wide variety of ocular disorders. Confocal scanning laser ophthalmoscopy, ultrasound biomicroscopy, confocal scanning laser polarimetry, color doppler imaging of blood flow, and optical coherence tomography are providing important information regarding disease pathophysiology, diagnosis, progression, and treatment. High frequency (50 MHz), high resolution ultrasound biomicroscopy of the anterior segment was obtained in a wide variety of disorders of the anterior segment. Tissue resolution is approximately 50 microns and the penetration depth is 5 mm. Ultrasound biomicroscopy is capable of imaging the comea, iris, anterior chamber, anterior chamber angle, posterior chamber, and ciliary body with great detail. The structures surrounding the posterior chamber, previously hidden from clinical observation, can be imaged and their normal anatomic relationships assessed. The various forms of angle closure glaucoma, such as pupillary block and plateau iris configuration, can be differentiated. The concave iris found in pigment dispersion and its response to treatment can be assessed. Visualization of anterior segment anatomy in eyes with opaque media is possible. Ultrasound biomicroscopy assists in the management of eyes with disorders of the anterior segment. Future applications of this technology will yield important information regarding accommodation, normal ocular physiology and disease pathophysiology.

  15. Molecular description of eye defects in the zebrafish Pax6b mutant, sunrise, reveals a Pax6b-dependent genetic network in the developing anterior chamber.

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    Masanari Takamiya

    Full Text Available The cornea is a central component of the camera eye of vertebrates and even slight corneal disturbances severely affect vision. The transcription factor PAX6 is required for normal eye development, namely the proper separation of the lens from the developing cornea and the formation of the iris and anterior chamber. Human PAX6 mutations are associated with severe ocular disorders such as aniridia, Peters anomaly and chronic limbal stem cell insufficiency. To develop the zebrafish as a model for corneal disease, we first performed transcriptome and in situ expression analysis to identify marker genes to characterise the cornea in normal and pathological conditions. We show that, at 7 days post fertilisation (dpf, the zebrafish cornea expresses the majority of marker genes (67/84 tested genes found also expressed in the cornea of juvenile and adult stages. We also characterised homozygous pax6b mutants. Mutant embryos have a thick cornea, iris hypoplasia, a shallow anterior chamber and a small lens. Ultrastructure analysis revealed a disrupted corneal endothelium. pax6b mutants show loss of corneal epithelial gene expression including regulatory genes (sox3, tfap2a, foxc1a and pitx2. In contrast, several genes (pitx2, ctnnb2, dcn and fabp7a were ectopically expressed in the malformed corneal endothelium. Lack of pax6b function leads to severe disturbance of the corneal gene regulatory programme.

  16. [Morphological analysis of alveolar bone of anterior mandible in high-angle skeletal class II and class III malocclusions assessed with cone-beam computed tomography].

    Science.gov (United States)

    Ma, J; Jiang, J H

    2018-02-18

    To evaluate the difference of features of alveolar bone support under lower anterior teeth between high-angle adults with skeletal class II malocclusions and high-angle adults presenting skeletal class III malocclusions by using cone-beam computed tomography (CBCT). Patients who had taken the images of CBCT were selected from the Peking University School and Hospital of Stomatology between October 2015 and August 2017. The CBCT archives from 62 high-angle adult cases without orthodontic treatment were divided into two groups based on their sagittal jaw relationships: skeletal class II and skeletal class III. vertical bone level (VBL), alveolar bone area (ABA), and the width of alveolar bone were measured respectively at the 2 mm, 4 mm, 6 mm below the cemento-enamel junction (CEJ) level and at the apical level. After that, independent samples t-tests were conducted for statistical comparisons. The ABA of the mandibular alveolar bone in the area of lower anterior teeth was significantly thinner in the patients of skeletal class III than those of skeletal class II, especially in terms of the apical ABA, total ABA on the labial and lingual sides and the ABA at 6 mm below CEJ level on the lingual side (Pclass III than those of skeletal class II, especially regarding the apical level on the labial and lingual side and at the level of 4 mm, 6 mm below CEJ level on the lingual side (Pclass III adult patients with high-angle when compared with the sample of high-angle skeletal class II adult cases. We recommend orthodontists to be more cautious in treatment of high-angle skeletal class III patients, especially pay attention to control the torque of lower anterior teeth during forward and backward movement, in case that the apical root might be absorbed or fenestration happen in the area of lower anterior teeth.

  17. Comparison of anterior segment morphology following prophylactic laser peripheral iridotomy in Caucasian and Chinese eyes.

    Science.gov (United States)

    Lee, Roland Y; Kasuga, Toshimitsu; Cui, Qi N; Huang, Guofu; He, Mingguang; Lin, Shan C

    2014-07-01

    To compare anterior segment biometric parameters between Caucasians and Chinese before and after laser peripheral iridotomy. Prospective clinical cohort study. Caucasian and Chinese primary angle-closure suspects. Anterior segment optical coherence tomography images captured before and after laser peripheral iridotomy were analysed to measure anterior segment biometric parameters. Paired Student's t-tests were used for within-ethnic group comparisons. Univariate and linear mixed-effect regression models were used for between-ethnic group comparisons. Angle opening distance, angle recess area, iris thickness, iris curvature, anterior chamber area, anterior chamber volume and anterior chamber width. Caucasians had significantly greater preoperative angle recess area, anterior chamber width, and iris curvature and lower preoperative iris thickness compared to Chinese (P iris curvature were observed within both ethnic groups (P iris curvature did not differ between the two ethnic groups (P iris convexity after laser peripheral iridotomy. Although certain aspects of anterior segment anatomy differed between Caucasians and Chinese preoperatively, they did not translate into significant ethnic differences in the amount of laser peripheral iridotomy-induced changes in the anterior segment biometric parameters. © 2013 Royal Australian and New Zealand College of Ophthalmologists.

  18. Ciliary body melanoma with limited nodular extrascleral extension and diffuse iris-angle infiltration treated by whole anterior segment plaque radiotherapy.

    Science.gov (United States)

    Gray, Michael E; Corrêa, Zélia M; Augsburger, James J; Barrett, William

    2007-08-01

    Primary uveal malignant melanoma of the ciliary body associated with nodular extrascleral extension, diffuse iris-angle infiltration, and secondary glaucoma is usually treated by prompt enucleation. We report a patient with ciliary body melanoma associated with nodular extrascleral extension and diffuse infiltration of the iris and angle treated conservatively because the fellow eye was blind. The clinical features and surgical management of a melanoma of the ciliary body with extrascleral extension and diffuse infiltration of the iris and angle are presented. The tumor was treated with focal I-125 plaque radiotherapy followed by supplemental whole anterior segment I-125 plaque radiotherapy. The patient has been followed for over 2.5 years since the initial plaque radiotherapy and over 1.5 years since the supplemental whole anterior segment radiotherapy. His visual acuity is correctable to 20/40 OD and there is no evidence of metastatic disease. His glaucoma is well controlled following trabeculectomy and tube shunt procedure. Whole anterior segment plaque radiotherapy for ciliary body melanoma with diffuse iris-angle infiltration provided palliative local tumor control without significant local complications through available follow-up.

  19. Intramuscular Pressure of Tibialis Anterior Reflects Ankle Torque but Does Not Follow Joint Angle-Torque Relationship

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    Filiz Ateş

    2018-01-01

    Full Text Available Intramuscular pressure (IMP is the hydrostatic fluid pressure that is directly related to muscle force production. Electromechanical delay (EMD provides a link between mechanical and electrophysiological quantities and IMP has potential to detect local electromechanical changes. The goal of this study was to assess the relationship of IMP with the mechanical and electrical characteristics of the tibialis anterior muscle (TA activity at different ankle positions. We hypothesized that (1 the TA IMP and the surface EMG (sEMG and fine-wire EMG (fwEMG correlate to ankle joint torque, (2 the isometric force of TA increases at increased muscle lengths, which were imposed by a change in ankle angle and IMP follows the length-tension relationship characteristics, and (3 the electromechanical delay (EMD is greater than the EMD of IMP during isometric contractions. Fourteen healthy adults [7 female; mean (SD age = 26.9 (4.2 years old with 25.9 (5.5 kg/m2 body mass index] performed (i three isometric dorsiflexion (DF maximum voluntary contraction (MVC and (ii three isometric DF ramp contractions from 0 to 80% MVC at rate of 15% MVC/second at DF, Neutral, and plantarflexion (PF positions. Ankle torque, IMP, TA fwEMG, and TA sEMG were measured simultaneously. The IMP, fwEMG, and sEMG were significantly correlated to the ankle torque during ramp contractions at each ankle position tested. This suggests that IMP captures in vivo mechanical properties of active muscles. The ankle torque changed significantly at different ankle positions however, the IMP did not reflect the change. This is explained with the opposing effects of higher compartmental pressure at DF in contrast to the increased force at PF position. Additionally, the onset of IMP activity is found to be significantly earlier than the onset of force which indicates that IMP can be designed to detect muscular changes in the course of neuromuscular diseases impairing electromechanical transmission.

  20. Gas gain operations with single photon resolution using an integrating ionization chamber in small-angle X-ray scattering experiments

    CERN Document Server

    Menk, R H; Besch, H J; Walenta, Albert H; Amenitsch, H; Bernstorff, S

    2000-01-01

    In this work a combination of an ionization chamber with one-dimensional spatial resolution and a MicroCAT structure will be presented. Initially, MicroCAT was thought of as a shielding grid (Frisch-grid) but later was used as an active electron amplification device that enables single X-ray photon resolution measurements at low fluxes even with integrating readout electronics. Moreover, the adjustable gas gain that continuously covers the entire range from pure ionization chamber mode up to high gas gains (30000 and more) provides stable operation yielding a huge dynamic range of about 10 sup 8 and more. First measurements on biological samples using small angle X-ray scattering techniques with synchrotron radiation will be presented.

  1. Corneal Collagen Cross-Linking Combined with an Artiflex Iris-Fixated Anterior Chamber Phakic Intraocular Lens Implantation in a Patient with Progressive Keratoconus

    Directory of Open Access Journals (Sweden)

    Sharif Hashmani

    2017-10-01

    Full Text Available We present here the case of a 24-year-old male who experienced progressive keratoconus and vision loss which adversely affected his ability to carry out everyday tasks. This landed him in the Hashmanis Hospital for consultation. He had a preoperative best corrected visual acuity of 6/12. He underwent multiple Oculus Pentacam examinations, which showed progressive keratoconus. Corneal collagen cross-linking (CXL was performed to stabilize his cornea and, subsequently, an Artiflex anterior chamber iris-fixated phakic intraocular lens (ACIF-PIOL was implanted to alleviate his refractive errors. The patient achieved a postoperative uncorrected visual acuity of 6/12. This report shows that CXL combined with ACIF-PIOL can be safe and effective in those with progressive keratoconus.

  2. Penetration of 45Ca in rabbit cornea following the introduction of air in the anterior chamber and its paracenthesis and following experimental intraocular hypertension

    International Nuclear Information System (INIS)

    Votockova, J.; Obenberger, J.; Babicky, A.

    1977-01-01

    In one group of Chinchilla rabbits the aqueous humor was withdrawn and the anterior chamber was refilled with air; in a second group only simple paracenthesis and withdrawal were performed; in a third group of animals experimental intraocular hypertension was produced by means of a subconjunctival injection of hypertonic sodium chloride. Immediately after these operations, a solution of 45 CaCl 2 was intravenously injected, and the rabbits were sacrificed after an interval of 30 min or 120 min. The corneas were excised and the radioactivity in central parts (trephined discs of 8 mm in diameter) and in remaining peripheral parts was determined. In all groups the corneal radioactivity in operated eyes exceeded the values found in the contralateral corneas of not operated eyes, radioactivity in these eyes being equal to the radioactivity found in the corneas of not operated rabbits in the control group. Various possible explanations of the increase of corneal radioactivity in operated eyes are briefly discussed. (author)

  3. The effect of Nd:YAG laser treatment of posterior capsule opacification on anterior chamber depth and refraction in pseudophakic eyes

    Directory of Open Access Journals (Sweden)

    Khambhiphant B

    2015-03-01

    Full Text Available Bharkbhum Khambhiphant,1 Chayata Liumsirijarern,2 Piyada Saehout1 1Department of Ophthalmology, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, 2Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand Purpose: This was a prospective descriptive study to determine the changes in intraocular lens (IOL position after neodymium-doped yttrium–aluminum–garnet (Nd:YAG laser posterior capsulotomy by measuring anterior chamber depth (ACD and refraction, including the spherical equivalent (SE and cylinder. Materials and methods: Forty-seven pseudophakic eyes with posterior capsule opacification of 29 patients were included. Nd:YAG laser posterior capsulotomy was performed. Patients’ ACD and refraction were measured before the treatment, as well as after the treatment at 1 week and 3 months. IOLMaster® and an automated refractometer were used at the Department of Ophthalmology, King Chulalongkorn Memorial Hospital, Bangkok, Thailand. Results: There were no statistically significant differences in ACD and SE before and after laser treatment at 1 week and 3 months (repeated analysis of variance, P=0.582 and P=0.269, respectively. Both backward IOL movement (number [n]=29 and forward IOL movement (n=18 were found. Some changes in cylindrical refraction were found at 1 week, but decreased at 3 months after capsulotomy (baseline cylinder: -1.16; cylinder at 1 week and 3 months: -1.00 and -1.14, respectively; P=0.012. These changes were the same with one-piece and three-piece IOLs. Conclusion: Nd:YAG laser posterior capsulotomy did not significantly change ACD and SE. It led to cylinder change at 1 week after laser, but the effect decreased at 3 months. This effect was small and may not be clinically significant. Keywords: posterior capsule opacification, neodymium-doped yttrium–aluminum–garnet, anterior chamber depth, pseudophakia, refraction

  4. Combined pars plana lensectomy-vitrectomy with open-loop flexible anterior chamber intraocular lens (AC IOL) implantation for subluxated lenses.

    Science.gov (United States)

    Kazemi, S; Wirostko, W J; Sinha, S; Mieler, W F; Koenig, S B; Sheth, B P

    2000-01-01

    To review our experience with combined pars plana lensectomy-vitrectomy and open-loop flexible anterior chamber intraocular lens (AC IOL) implantation for managing subluxated crystalline lenses. Retrospective review of 36 consecutive eyes (28 patients), all of which had subluxated crystalline lenses, managed by pars plana lensectomy-vitrectomy with insertion of an open-loop flexible AC IOL. The study was performed at the Medical College of Wisconsin, Milwaukee, over an 8-year period. An average preoperative visual acuity of 20/163 (range, 20/25 to hand motions) improved to 20/36 (range, 20/20 to 4/200) with surgery after a mean follow-up of 14 months (range, 1 to 59 months) (P IOL implantation appears to be an excellent technique for managing subluxated crystalline lenses. It is associated with a significant improvement in visual acuity (P subluxated lens through a limbal wound. Additionally, use of an AC IOL offers a simplified alternative to placement of a ciliary sulcus sutured posterior chamber intraocular lens (PC IOL).

  5. Outcomes of iris-claw anterior chamber versus iris-fixated foldable intraocular lens in subluxated lens secondary to Marfan syndrome.

    Science.gov (United States)

    Hirashima, Denise E; Soriano, Eduardo S; Meirelles, Rodrigo L; Alberti, Gustave N; Nosé, Walton

    2010-08-01

    To compare the outcome of phacoemulsification using 2 different iris-fixation techniques for intraocular lens (IOL) replacement, a foldable posterior chamber IOL (PCIOL; AcrySof MA60AC, Alcon Laboratories Inc, Fort Worth, TX) and an iris-claw anterior chamber IOL (ACIOL; Artisan, Ophtec BV), for treatment of subluxated lenses in patients with Marfan syndrome (MFS). Randomized, controlled trial. A total of 31 eyes of 16 patients with subluxated lenses associated with MFS and a preoperative corrected visual acuity (CVA) IOL type. Preoperative and postoperative ophthalmologic examination, optical coherence tomography, and endothelial cell counts were performed. We recorded CVA results at 3, 6, and 12 months, complications, endothelial cell loss, and central retinal thickness. In the iris-fixated PCIOL group, CVA was significantly improved at 3 (P = 0.011; n = 16), 6 (P = 0.006; n = 16), and 12 months (P = 0.002; n = 16). In the iris-claw ACIOL group, CVA was significantly improved at 3 (P = 0.001; n=15), 6 (P = 0.001; n = 15), and 12 months (P = 0.009; n = 12). The CVA results did not differ significantly between groups. Dislocation of the IOL occurred in 3 of 16 (18.75%) eyes in the PCIOL group. Retinal detachment occurred in 3 eyes (2 in the PCIOL group and 1 in the ACIOL group) and was successfully repaired. Postoperative foveal tomograms in both groups revealed a decrease in the mean foveal thickness (MFT; IOL dislocation tended to occur more frequently in the iris-fixated PCIOL group, the difference was not significant. At 6 months postoperatively, all study patients tended to have a thinner MFT. None of the patients in either group developed cystoid macular edema. Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  6. Intra- and inter-rater reliabilities of measurement of ultrasound imaging for muscle thickness and pennation angle of tibialis anterior muscle in stroke patients.

    Science.gov (United States)

    Cho, Ki Hun; Lee, Hwang Jae; Lee, Wan Hee

    2017-07-01

    Dysfunction of skeletal muscle has been commonly reported in stroke patients. The purpose of this study was to investigate the intra- and inter-rater reliabilities of measurement of ultrasound imaging (USI) for pennation angle (PA) and muscle thickness (MT) of tibialis anterior muscle in stroke patients. Thirty-four stroke patients (19 men) participated in this study. USI was used for measurement of PA and MT of the tibialis anterior muscles at rest and during maximum voluntary contraction (MVC). Two examiners acquired images from all participants during two separate testing sessions, seven days apart. Intra-class correlation coefficients (ICCs), confidence interval (CI), standard error of measurement, minimal detectable change, and Bland-Altman plots were used for estimation of reliability. In the intra-rater reliability between measures, for all variables (PA and MT of the paretic and non-paretic sides of tibialis anterior muscles at rest and during MVC), the ICCs ranged between 0.639 and 0.998 and the CI was within an acceptable range of 0.388-0.999. In inter-rater reliability between examiners for the two tests, for all variables, the ICCs ranged between 0.690 and 0.995 and the CI was within an acceptable range of 0.463-0.997. In addition, significant difference was observed between the paretic and non-paretic sides of the tibialis anterior muscle architecture (p stroke patients. In addition, objective and quantitative measurements of tibialis anterior muscle using USI may provide appropriate management for the walking recovery of stroke patients.

  7. Application of Anterior Segment Optical Coherence Tomography in Pediatric Ophthalmology

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    Ricardo Salles Cauduro

    2012-01-01

    Full Text Available Purpose. Application of anterior segment optical coherence (AS-OCT in pediatric ophthalmology. Methods. Retrospective clinical study case series of 26 eyes of 19 pediatric patients throughout a 21-month period, presenting anterior segment pathologies, were submitted to AS-OCT examination (OCT Visante, 1310 nm, Zeiss, noncontact technique, no sedation requirement. Results. AS-OCT images were obtained from 19 patients (range: 2 months to 12 years. Clinical diagnosis of anterior segment abnormalities included cornea disease (n=7, congenital anterior segment conditions (n=10, ocular trauma (n=1, anterior segment surgeries (n=2, iridocorneal angle abnormalities (n=4, intermediate uveitis (n=2. The most common OCT findings were corneal hyperreflectivity and thickening (n=15, shallow anterior chamber with iris-lens diaphragm anterior displacement (n=4, atypical corneal curvature (n=4, corneal thinning (n=4, peripheral synechiae with angle closure (n=3, increased anterior chamber depth (n=2, and proximal portion of glaucoma drainage tube (n=2. Conclusion. In the present study, noncontact AS-OCT demonstrated to be a feasible technique to evaluate the anterior segment providing anatomic details and useful to clarify diagnosis in the pediatric population.

  8. Influences of knee flexion angle and portal position on the location of femoral tunnel outlet in anterior cruciate ligament reconstruction with anteromedial portal technique.

    Science.gov (United States)

    Osaki, Kanji; Okazaki, Ken; Tashiro, Yasutaka; Matsubara, Hirokazu; Iwamoto, Yukihide

    2015-03-01

    To evaluate the influences of knee flexion angle and portal position on the location of femoral tunnel outlet in anterior cruciate ligament (ACL) reconstruction with the anteromedial (AM) portal technique. We recruited 6 volunteers with 12 normal knees. Each knee was flexed 120° or 135° and scanned with an open MRI. A 3D knee model was created. Virtual femoral tunnels were created on the footprint of the AM bundle and the posterolateral (PL) bundle of the ACL from three arthroscopic portals: the standard AM portal, the far medial and low portal, and the far medial and high (FMH) portal. The location of the femoral tunnel outlet was evaluated by comparing to the dissected cadaveric knee. Both increased flexion angle and lowering the drilling portal have a similar influence on the femoral tunnel outlet by moving them anterior and distally. Medialization of the portal moves them posteriorly and distally. PL tunnels created on the 120° knee model are more likely to be located under the lateral head of the gastrocnemius especially when they are drilled through the AM or FMH portals. If the femoral tunnel outlet is located under the soft tissue such as gastrocnemius attachment, suspension fixation devices may lapse into fixation failure by sitting on the soft tissue rather than the cortex bone surface. It is more desirable to drill in 135° knee flexion rather than 120°, and through a lower portal, to avoid creating the femoral tunnel outlet under soft tissues.

  9. Relationship between screw sagittal angle and stress on endplate of adjacent segments after anterior cervical corpectomy and fusion with internal fixation: a Chinese finite element study.

    Science.gov (United States)

    Zhang, Yu; Tang, Yibo; Shen, Hongxing

    2017-12-01

    In order to reduce the incidence of adjacent segment disease (ASD), the current study was designed to establish Chinese finite element models of normal 3rd~7th cervical vertebrae (C3-C7) and anterior cervical corpectomy and fusion (ACCF) with internal fixation , and analyze the influence of screw sagittal angle (SSA) on stress on endplate of adjacent cervical segments. Mimics 8.1 and Abaqus/CAE 6.10 softwares were adopted to establish finite element models. For C4 superior endplate and C6 inferior endplate, their anterior areas had the maximum stress in anteflexion position, and their posterior areas had the maximum stress in posterior extension position. As SSA increased, the stress reduced. With an increase of 10° in SSA, the stress on anterior areas of C4 superior endplate and C6 inferior endplate reduced by 12.67% and 7.99% in anteflexion position, respectively. With an increase of 10° in SSA, the stress on posterior areas of C4 superior endplate and C6 inferior endplate reduced by 9.68% and 10.22% in posterior extension position, respectively. The current study established Chinese finite element models of normal C3-C7 and ACCF with internal fixation , and demonstrated that as SSA increased, the stress on endplate of adjacent cervical segments decreased. In clinical surgery, increased SSA is able to play important role in protecting the adjacent cervical segments and reducing the incidence of ASD.

  10. Does anterior knee pain severity and function relate to the frontal plane projection angle and trunk and hip strength in women with patellofemoral pain?

    Science.gov (United States)

    Almeida, Gabriel Peixoto Leão; Carvalho E Silva, Ana Paula de Moura Campos; França, Fábio Jorge Renovato; Magalhães, Maurício Oliveira; Burke, Thomaz Nogueira; Marques, Amélia Pasqual

    2015-07-01

    The aim of the present study was to determine the relationship between knee pain severity and function with the frontal plane projection angle (FPPA) and trunk and hip peak torque (PT) in women with patellofemoral pain (PFPS). Twenty-two women with PFPS were assessed. Knee pain severity (KPS) was assessed with an 11-point visual analog scale and function with an Anterior Knee Pain Scale. The FPPA was recorded with a digital camera. PT of extensors, abductors, and the lateral rotators of hip and lateral core stability were measured with a handheld dynamometer. FPPA was the only predictor for the KPS. Regarding predictors of function, PT of lateral core stability and the extensor and abductor of the hip explained 41.4% of the function. Increase in FPPA was associated with greater KPS, and the lowest PT of lateral core stability, hip abductors, and extensors was associated with lower function in women with PFPS. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Laser peripheral iridoplasty for angle-closure.

    Science.gov (United States)

    Ng, Wai Siene; Ang, Ghee Soon; Azuara-Blanco, Augusto

    2012-02-15

    Angle-closure glaucoma is a leading cause of irreversible blindness in the world. Treatment is aimed at opening the anterior chamber angle and lowering the IOP with medical and/or surgical treatment (e.g. trabeculectomy, lens extraction). Laser iridotomy works by eliminating pupillary block and widens the anterior chamber angle in the majority of patients. When laser iridotomy fails to open the anterior chamber angle, laser iridoplasty may be recommended as one of the options in current standard treatment for angle-closure. Laser peripheral iridoplasty works by shrinking and pulling the peripheral iris tissue away from the trabecular meshwork. Laser peripheral iridoplasty can be used for crisis of acute angle-closure and also in non-acute situations.   To assess the effectiveness of laser peripheral iridoplasty in the treatment of narrow angles (i.e. primary angle-closure suspect), primary angle-closure (PAC) or primary angle-closure glaucoma (PACG) in non-acute situations when compared with any other intervention. In this review, angle-closure will refer to patients with narrow angles (PACs), PAC and PACG. We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2011, Issue 12), MEDLINE (January 1950 to January 2012), EMBASE (January 1980 to January 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 5 January 2012. We included only randomised controlled trials (RCTs) in this review. Patients with narrow angles, PAC or PACG were eligible. We excluded studies that included only patients with acute presentations

  12. Association of ocular conditions with narrow angles in different ethnicities.

    Science.gov (United States)

    Lee, Roland Y; Chon, Brian H; Lin, Shuai-Chun; He, Mingguang; Lin, Shan C

    2015-09-01

    To quantify the predictive strength of anterior chamber area (ACA), anterior chamber volume (ACV), anterior chamber width (ACW), lens vault (LV), iris thickness (IT), and iris area (IArea) for 2 angle width parameters, trabecular-iris space area (TISA750) and angle opening distance (AOD750) at 750 μm from the scleral spur, in different ethnicities. Prospective, cross-sectional study. Anterior segment optical coherence tomography images for 166 white, 90 African, 75 Hispanic, and 132 Chinese subjects were analyzed. First, ACA, ACV, ACW, LV, IT, and IArea were compared among ethnic groups. Second, associations of TISA750 and AOD750 with ACA, ACV, ACW, LV, IT, and IArea were investigated within each ethnic group using multivariable linear regression models, standardized regression coefficients (β), and coefficients of determination (R(2)). Significant ethnic differences were observed in ACA, ACV, ACW, LV, IT, and IArea (all P ACV, and LV were significant predictors of TISA750 and AOD750 in all ethnic groups (all P ACV, and LV had the highest predictive strength for both TISA750 and AOD750 in all ethnic groups based on β and R(2). Despite ethnic differences in ACA, ACV, ACW, LV, IT, and IArea, the same 3 anterior segment parameters (ACA, ACV, and LV) were the strongest predictors of angle width (TISA750 and AOD750) in all 4 ethnic groups. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Modified dark room provocative test for primary angle closure.

    Science.gov (United States)

    Li, Dejiao; Wang, Ningli; Wang, Bingsong; Wang, Tao; Jonas, Jost B

    2012-03-01

    To examine the diagnostic value of a modified dark room provocative test (DRPT) in detecting primary closure of the anterior chamber angle. The cross-sectional observational prospective clinical study included suspects of primary angle closure. Using anterior segment optical coherence tomography (AS-OCT), we measured the anterior chamber angle configuration at room light and after 3 minutes of dark adaptation. Gonioscopy and Perkin's applanation tonometry were performed in room light conditions at baseline and after 1.5 hours of dark adaptation. The number of closed angle quadrants assessed on AS-OCT images and upon gonioscopy were recorded. The DRPT was positive, if intraocular pressure increased by ≥8 mm Hg after 1.5 hours of dark adaptation. The study included 76 subjects (76 eyes). Among 32 (42%) eyes with a positive DRPT, the number of eyes with an increased number of closed angle quadrants was significantly higher for the OCT examination at 3 minutes of dark adaptation than for gonioscopy at 1.5 hours of dark adaptation [29 (91%) eyes vs 21 (66%) eyes; P=0.01]. Kappa statistics showed a moderate agreement between increased closed angle quadrants obtained both after 3 minutes of dark adaptation (κ=0.44; Pdark room test (κ=0.45; Pdark room test. A modified DRPT with an anterior chamber angle assessment by OCT at 3 minutes of dark adaptation as compared with a gonioscopic angle assessment after 1.5 hours of dark adaptation had a higher diagnostic precision in predicting primary angle closure.

  14. Contaminação bacteriana da câmara anterior pós-facoemulsificação com implante de lente intra-ocular de polimetilmetacrilato ou silicone Bacterial anterior chamber contamination after phacoemulsification and polymethylmethacrylate or silicone intraocular lens implantation

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    Ricardo Antonio Pereira

    2004-12-01

    Full Text Available OBJETIVO: Avaliar a contaminação bacteriana da câmara anterior, após facoemulsificação não complicada, com tamanhos diferentes de incisões e lentes intra-oculares. MÉTODOS: Foi realizado estudo prospectivo randomizado, de 80 olhos de 80 pacientes, submetidos à facoemulsificação sob anestesia tópica, distribuídos aleatoriamente em dois grupos iguais. No grupo A foram alocados os pacientes submetidos à cirurgia com incisão de 3,0 mm, lente intra-ocular dobrável de silicone implantadas com injetor. No grupo B os pacientes foram submetidos à cirurgia com incisão de 5,8 mm e implante de lente intra-ocular de polimetilmetacrilato de peça única, com pinça. Ao final de cada cirurgia, uma amostra do líquido da câmara anterior foi colhida e semeada em meios de cultura para bactérias. RESULTADOS: A cultura do líquido da câmara anterior foi positiva em 2,5% dos casos do grupo A e em 5,0% do grupo B. Não houve diferença estatisticamente significante entre os dois grupos (chi2 = 0, 380, p> 0,05. CONCLUSÃO: O implante de lente intra-ocular através de incisão menor, não resultou em menor contaminação da câmara anterior na cirurgia de facoemulsificação.PURPOSE: To evaluate bacterial anterior chamber contamination following uncomplicated phacoemulsification with differents sizes of incisions. METHODS: Prospective randomized study, 80 eyes, 80 patients divided into two groups, were submitted to phacoemulsification with topical anaesthesia. In group A, with 40 patients, surgery was perfomed with 3.0 mm incision and silicone intraocular lens implant with injector. In group B the surgery was done with 5.8 mm incision and polymethylmethacrylate intraocular lens implant with forceps. Anterior chamber aspirate was taken for culture upon completion of surgery in each case. RESULTS: Anterior chamber cultures were positive in 2.5% of the cases in group A, and 5.0% in group B (chi-square test = 0.380, p>0.05, frequencies of

  15. [Dynamics of riboflavin level in aqueous humour of anterior chamber of experimental animals under standard stroma saturation by ultraviolet corneal cross-linking solutions].

    Science.gov (United States)

    Bikbov, M M; Shevchuk, N E; Khalimov, A R; Bikbova, G M

    To evaluate the dynamics of riboflavin changes in the aqueous humour of the anterior chamber (AHAC) of rabbits' eyes during standard ultraviolet (UV) cross-linking with account to the area of corneal debridement. Forty two rabbits were studied sequentially. The following solutions of riboflavin were used for cornea saturation: IR - 0.1% isosmotic riboflavin, D - Dextralink (0.1% riboflavin with 20% dextran), R - 0.1% riboflavin with 1.0% hydroxypropylmethylcellulose (HPMC). Each solution was evaluated in 3 groups that differed in the diameter of corneal debridement: group 1 - Epi-Off 3 mm (IR-3, D-3, P-3), group 2 - Epi-Off 6 mm (IR-6, D-6, R-6), and group 3 - Epi-Off 9 mm (IR-9, D-9, R-9). Aqueous humour sampling (252 samples in total) was performed in 10-minute intervals within a 60 minute period. Riboflavin levels were measured by enzyme-linked immunoassay (ID-Vit microbiological test system; Immundiagnostik, Germany). Stable growth rates of riboflavin level in the AHAC (with maximum values reached at 30-40 min) were observed for solutions D and R, regardless of the variant of corneal debridement. Moreover, throughout the whole follow-up period and regardless of the area of corneal debridement, the solution D provided a relatively lower concentration of riboflavin in the AHAC as compared to the two other solutions. At 30 minutes, when the cornea was considered ready for UV irradiation, the riboflavin level in the AHAC ranged from 385±26.1 μg/l (D-9) to 665±28 μg/l (R-9). In groups IR-9, IR-6, P-6, IR-3, and P-3 riboflavin levels were found to be in the same range starting at 20 minutes. However, even a sufficient concentration of riboflavin in the cornea or AHAC cannot guarantee safe and effective UV cross-linking, since the removed epithelium limits the area of the stroma that can be saturated with riboflavin, while the area of UV exposure is 8-10 mm. Safe and efficient standard UV cross-linking may be performed only under sufficient saturation of the

  16. Spontaneous, late, in-the-bag intraocular lens subluxation in a patient with a previous acute angle-closure glaucoma attack.

    Science.gov (United States)

    Su, Wei-Wen; Chang, Shirley H L

    2004-08-01

    Cataract surgery was performed in a 49-year-old woman 16 months after an acute angle-closure glaucoma attack. Zonular dialysis was observed during surgery, but the intraocular lens (IOL) was implanted in the capsular bag uneventfully. At 4 1/2 months, 1 IOL loop wrapped in the bag herniated into the anterior chamber. The patient had no history of trauma. The IOL loop remained in the anterior chamber for 9 months, until the subluxated IOL spontaneously returned to its original position. Six months later, the IOL again dislocated into the anterior chamber.

  17. Fixed-Angle, Posteriorly Connected Anterior Cage Reconstruction Improves Stiffness and Decreases Cancellous Subsidence in a Spondylectomy Model.

    Science.gov (United States)

    Colman, Matthew W; Guss, Andrew; Bachus, Kent N; Spiker, W Ryan; Lawrence, Brandon D; Brodke, Darrel S

    2016-05-01

    An idealized biomechanical model. The aim of this study was to evaluate the biomechanical properties of a construct designed to minimize intervertebral cage subsidence and maximize stiffness. Reconstruction after vertebral resection typically involves posterior segmental fixation and anterior interbody support. However, poor bone density, adjuvant radiation, or the oncologic need for endplate resection make interbody device subsidence and resultant instrumentation failure a significant concern. An idealized thoracolumbar spondylectomy reconstruction model was constructed using titanium segmental instrumentation and Delrin plastic. In vivo mechanical stress was simulated on a custom multi-axis spine simulator. Rigid body position in space was measured using an optical motion-capture system. Cancellous subsidence was modeled using a 1 cm thick wafer of number 3 closed-cell Sawbones foam at one endplate. Ten foam specimens were tested in a control state consisting of posterior segmental fixation with a free interbody cage. Ten additional foam specimens were tested in the test state, with the Delrin interbody cage "connected" to the posterior rods using two additional pedicle screws placed into the cage. Foam indentation was quantified using a precision digital surface-mapping device, and subsidence volume calculated using geometric integration. The control group exhibited significantly greater foam indentation after cycling, with a mean subsidence volume of 1906 mm [95% confidence interval (95% CI) 1810-2001] than the connected cage group subsidence volume of 977 mm (95% CI 928-1026 mm; P subsidence compared with a traditional unconnected cage. N/A.

  18. Comparative analysis of the anterior and posterior length and deflection angle of the cranial base, in individuals with facial Pattern I, II and III

    Directory of Open Access Journals (Sweden)

    Guilherme Thiesen

    2013-02-01

    Full Text Available OBJECTIVE: This study evaluated the variations in the anterior cranial base (S-N, posterior cranial base (S-Ba and deflection of the cranial base (SNBa among three different facial patterns (Pattern I, II and III. METHOD: A sample of 60 lateral cephalometric radiographs of Brazilian Caucasian patients, both genders, between 8 and 17 years of age was selected. The sample was divided into 3 groups (Pattern I, II and III of 20 individuals each. The inclusion criteria for each group were the ANB angle, Wits appraisal and the facial profile angle (G'.Sn.Pg'. To compare the mean values obtained from (SNBa, S-N, S-Ba each group measures, the ANOVA test and Scheffé's Post-Hoc test were applied. RESULTS AND CONCLUSIONS: There was no statistically significant difference for the deflection angle of the cranial base among the different facial patterns (Patterns I, II and III. There was no significant difference for the measures of the anterior and posterior cranial base between the facial Patterns I and II. The mean values for S-Ba were lower in facial Pattern III with statistically significant difference. The mean values of S-N in the facial Pattern III were also reduced, but without showing statistically significant difference. This trend of lower values in the cranial base measurements would explain the maxillary deficiency and/or mandibular prognathism features that characterize the facial Pattern III.OBJETIVO: o presente estudo avaliou as variações da base craniana anterior (S-N, base craniana posterior (S-Ba, e ângulo de deflexão da base do crânio (SNBa entre três diferentes padrões faciais (Padrão I, II e III. MÉTODOS: selecionou-se uma amostra de 60 telerradiografias em norma lateral de pacientes brasileiros leucodermas, de ambos os sexos, com idades entre 8 anos e 17 anos. A amostra foi dividida em três grupos (Padrão I, II e III, sendo cada grupo constituído de 20 indivíduos. Os critérios de seleção dos indivíduos para cada grupo

  19. Comparative biometric study between plateau iris configuration and primary open angle glaucoma with narrow angle.

    Science.gov (United States)

    Diniz Filho, Alberto; Cronemberger, Sebastião; Mérula, Rafael Vidal; Calixto, Nassim

    2009-01-01

    To investigate biometrically the differences between plateau iris configuration (PIC) eyes and primary open angle glaucoma with narrow angle eyes. A comparative study involving a case series with 20 eyes of 11 plateau iris configuration patients and 45 eyes of 27 primary open angle glaucoma with narrow angle eyes patients was done. The following measurements were taken: corneal curvature, central corneal thickness, anterior chamber depth, lens thickness (LT), axial length (AL), lens thickness and axial length ratio, lens position (LP) and relative lens position (RLP). The plateau iris configuration eyes presented a higher corneal cuvature value than primary open angle glaucoma with narrow angle eyes eyes but not with clinical and statistical difference (P=0.090). The plateau iris configuration eyes demonstrated a higher central corneal thickness, with statistical significance, when compared to primary open angle glaucoma with narrow angle eyes (P=0.010). Statistical significant difference between plateau iris configuration and primary open angle glaucoma with narrow angle eyes was found in axial length (21.69 +/- 0.98 vs. 22.42 +/- 0.89; P=0.003). No significant difference was found when anterior chamber depth (2.62 +/- 0.23 vs. 2.71 +/- 0.31; P=0.078), LT (4.67 +/- 0.36 vs. 4.69 +/- 0.45; P=0.975), LT/AL (2.16 +/- 0.17 vs. 2.10 +/- 0.21; P=0.569), LP (4.95 +/- 0.25 vs. 5.06 +/- 0.34; P=0.164) and RLP (0.23 +/- 0.01 vs. 0.22 +/- 0.14; P=0.348) were evaluated. The eyes with plateau iris configuration presented statistical significantly shorter axial length and higher central corneal thickness than primary open angle glaucoma with narrow angle eyes.

  20. The effect of pharmacologic pupillary dilatation on anterior segment parameters in patients with exfoliation syndrome

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    Mehmet Cem Mocan

    2014-01-01

    Conclusion: Pupillary dilatation with a single drop of 1.0% cyclopentolate, 2.5% phenylephrine or 1% tropicamide is not associated with shallowing of the anterior chamber or narrowing of the ACA in patients with XFS who present with open angles.

  1. Estudo cefalométrico das alturas faciais anterior e posterior, em crianças brasileiras, portadoras de má oclusão Classe I de Angle, na fase de dentadura mista Cephalometric study of the anterior and posterior facial heights in brazilian children, presenting Angle Class I malocclusion, in the mixed dentition

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    Arno Locks

    2005-04-01

    Full Text Available Realizou-se um estudo das alturas faciais anterior e posterior em 79 crianças brasileiras, sendo 46 do gênero feminino e 33 do masculino, com idades de 8 a 11 anos, portadoras de má oclusão Classe I de Angle, na fase de dentadura mista, não submetidas a tratamento ortodôntico. Esta investigação utilizou duas radiografias cefalométricas em norma lateral, de cada criança, com intervalo de 8 a 16 meses entre uma radiografia e outra, para comparação dos dados cefalométricos. Foram estudadas as proporções faciais anteriores, ou seja, a relação entre as dimensões N-Me (AFT, N-ENA (AFS, ENA-Me (AFI e o relacionamento entre as dimensões Ar-GO (AFP e a distância entre o plano palatino ao mento (AFA , isto é, o Índice da Altura Facial (IAF. Os resultados obtidos, possibilitaram constatar que as tendências de crescimento foram equilibradas em todas as situações estudadas; a dimensão altura facial inferior, contribuiu de forma mais significativa, nas alterações observadas na altura facial total; as proporções faciais anteriores se mantiveram em torno de 42% para a altura facial superior e 58% para a altura facial inferior; o índice da altura facial ou se manteve constante em torno de 0,66 ou apresentou uma tendência a aumentar com a idade; não ocorreu dimorfismo sexual com relação às proporções faciais e índice da altura facial.The objective of this study was to evaluate the anterior and posterior facial heights in 79 non orthodontic brazilian children, 46 females and 33 males, from 8 to 11 years old, presenting Angle Class I malocclusion, in the mixed dentition. Two lateral cephalometric radiographs were taken, with a time interval ranging from 8 to 16 months between radiographs in order to compare the cephalometric data. The anterior facial proportions were studied, based in following dimensions: N-Me (AFT, N-ENA (AFS e ENA-Me (AFI. The Facial Height Index (IAF was also evaluated taking in account the relationship

  2. Angled screw holes for anterior posts and a frame-positioning device for gamma knife radiosurgery: allowing for better targeting of intracranial lesions.

    Science.gov (United States)

    Quiñones-Hinojosa, Alfredo; McDermott, Michael W

    2007-04-01

    Gamma knife radiosurgery requires frame positioning so that the treatment target is as close to the center of the frame and as low as possible to cover all of the posterior fossa contents. In this study, we report the use of two devices developed by the senior author (MWM) that facilitate these two crucial objectives in the treatment of intracranial targets using the gamma knife. Custom front posts with threaded screw holes drilled at 5-, 10-, and 15-degree angles were created by the manufacturer at our request. A U-shaped metal device for frame positioning was designed in-house and fits into the holes at the 100-mm mark on the lateral sides of the Leksell stereotactic frame base. This allowed the positioning device to snap securely into the frame for use in positioning. The positioning device was constructed so that the lowest possible frame position would be achieved with each frame application, while avoiding collisions with the magnetic resonance imaging localizer box. Angled front posts allowed for pin contacts with the cranium anterior and/or superior to the superior temporal line despite a lateral or posterior position of the frame. This avoided penetration of the temporalis muscle and reduced discomfort for patients. The U-shaped metal device was used in place of the Velcro straps or ear bars routinely used for frame positioning in which the distance from the frame base to the top of the head must always be measured to avoid collisions with the localizer box. During the past 2 years, these devices have been used on a daily basis, achieving the desired results. In many cases, their use has avoided the need for frame repositioning and rescanning for targets that cannot be reached because of inexact frame positioning. A new design with angled screw holes in the front posts used for gamma knife radiosurgery allows surgeons to avoid penetration of the temporalis muscle and to maintain a perpendicular orientation of the fixation screw to the outer table of the

  3. [Laser Iridotomy - In Cases of Acute Angle Closure Only?

    Science.gov (United States)

    Handzel, Daniel M; Meyer, Carsten H; Wegener, Alfred

    2017-11-01

    The narrowing of the chamber angle-as a result of anatomic predispositions like high hyperopia or increasing lens thickness-poses the greatest risk for acute angle closure. A laser iridotomy counts as a standard procedure in cases of acute angle closure, whereas there are no coherent recommendations or guidelines for a prophylactic therapy. Modern imaging techniques, such as anterior segment optical coherence tomography or Scheimpflug photography, can give valuable information for the planning of treatment. This review presents traditional and modern imaging techniques and summarises recommendations for action in relation to recent publications. Georg Thieme Verlag KG Stuttgart · New York.

  4. Anterior segment optical coherence tomography for the quantitative evaluation of the anterior segment following Boston keratoprosthesis.

    Directory of Open Access Journals (Sweden)

    Joann J Kang

    Full Text Available OBJECTIVE: To quantitatively evaluate the anterior segment using anterior segment optical coherence tomography (AS-OCT following Boston keratoprosthesis type 1. METHODS: A retrospective study consisted of AS-OCT imaging at a single time point postoperatively in 52 eyes. Main outcomes measures include anatomical and functional anterior chamber depth (ACD, angle (ACA and peripheral and proximal synechiae. RESULTS: The mean time point of imaging was 19.3 months postoperatively. Average anatomical and functional ACD was 2.0 and 0.21 mm respectively, and mean ACA ranged from 2.5° to 6.14° in representative meridians. An average of 8.7 clock hours of angle closure was observed in the 25 eyes in which all meridians were imaged. The majority of eyes showed peripheral (86.5% and proximal (67.3% synechiae. CONCLUSIONS: AS-OCT is a useful tool for quantitative evaluation of anterior segment and angle after keratoprosthesis, which is otherwise poorly visible. The majority of eyes showed shallow ACD, extensive angle closure and synechiae formation.

  5. Clinical study of phacoemulsification and goniosynechialysis for primary angle-closure glaucoma

    Directory of Open Access Journals (Sweden)

    Jing He

    2015-07-01

    Full Text Available AIM:To discuss the clinical effect and safety of the combined surgeries of phacoemulsification and goniosynechialysis for patients with primary angle-closure glaucoma(PACG. METHODS: Eighty-three eyes of 83 patients with PACG and cataract were ranomized into two groups. Group A: 39 patients with 39 eyes of angle-closure RESULTS: The visual acuity was improved significantly in both group after operation. No significantly difference in ACD, anterior chamber angle after operation in two groups(P>0.05. The IOP in group A was lower than that in group B 3mo after operation, there was statistical significance(PCONCLUSION:Phacoemulsification and goniosynechialysis can deepen ACD significantly. This method make the anterior chamber angle open, can reduce IOP and improve the patients' visual acuity, especially in patients with PACG. It is a safe and effective approach to patients with PACG and cataract.

  6. EFFECTS OF FLUNIXIN MEGLUMINE CONJUNCTIVAL SHOT OVER THE HUMOR AQUEOUS PROTEIN OF DOGS SUBMITTED TO THE PARACENTESIS OF THE ANTERIOR CHAMBER AVALIAÇÃO DOS EFEITOS DA FLUNIXINA MEGLUMINA, POR VIA SUBCONJUNTIVAL, SOBRE A CONCENTRAÇÃO E PADRÃO PROTEICO DO HUMOR AQUOSO DE CÃES SUBMETIDOS À PARACENTESE DA CÂMARA ANTERIOR

    OpenAIRE

    Paula Diniz Galera; José Luiz Laus; Ana Maria Barros Soares; Cassio Ricardo Ribeiro; Francislette Rodrigues de Melo

    2009-01-01

    Flunixin meglumine effects, over aqueous humor proteins of eyes on dogs who were submitted to paracentesis of the anterior chamber, were evaluated. To ten adult dogs clinically healthy were given a subconjunctival shot with flunixin meglumine (1.1mg/Kg) on the right eye and sterilized saline solution 0.9% on the left eye, with the same volume. After general anesthesia, were submitted to two paracentesis of the both eyes to collect 0.2mL of first and second aqueous. The samples were...

  7. Avaliação da contaminação da câmara anterior na cirurgia de facoemulsificação com implante de lente intra-ocular Anterior chamber contamination in phacoemulsification surgery with intraocular lens implant

    Directory of Open Access Journals (Sweden)

    Cesar Nobuo Shiratori

    2002-06-01

    Full Text Available Objetivo: Avaliar a existência de contaminação da câmara anterior durante a facectomia por facoemulsificação com implante de lente intra-ocular. Método: Foi realizado estudo prospectivo, avaliando-se 30 pacientes submetidos a facectomia por facoemulsificação com implante de lente intra-ocular, colhendo-se duas amostras de humor aquoso, uma obtida no início e outra no final da cirurgia. As amostras foram semeadas em meio de cultura para germes aeróbios, anaeróbios e fungos. Resultado: Todas as amostras avaliadas resultaram negativas. Conclusão: A contaminação da câmara anterior na cirurgia de facoemulsificação com implante de lente intra-ocular, usando os cuidados necessários, é infreqüente.Purpose: To evaluate the frequency of anterior chamber contamination during phacoemulsification surgery with intraocular lens implant. Method: A prospective study was done with 30 patients submitted to phacoemulsification surgery with intraocular lens implant. Two samples of the aqueous humor were removed from the anterior chamber, one at the beginning and another one at the end of the surgery and were inoculated in culture plates for anaerobic and aerobic bacteria and fungi. Results: Intraocular aspirates yielded negative cultures. Conclusion: The absence of microorganisms in the samples evaluated allowed us to conclude that contamination during the phacoemulsification surgery with lens implant is unusual.

  8. A New Approach on Output Current Calculation for Thimble-type Ionization Chamber with Variation of Gamma-ray Irradiation Angle

    International Nuclear Information System (INIS)

    Kim, Jae Cheon; Kim, Soon Young; Kim, Yong Kyun; Kim, Jong Kyung

    2006-01-01

    The output current of an ionization chamber is directly connected with the size of the active volume and ion-pair distribution in air volume. Their accurate assessments are significantly important in order to analyze the design characteristics of an ionization chamber and interpret the measurements with it. It has been generally assumed that ion-pairs are generated uniformly in air volume for simplicity although they are not uniformly distributed due to various source and geometry conditions. Ion-pair distribution is mainly dependent on the irradiation source conditions, while active volume is deeply related to the ionization chamber design. Therefore, such assumption should be examined if the ion-pair distribution affects real output current of the active volume defined by electric field. A new analytical approach considering both electric field and ion-pair nonuniformity has been proposed to analyze accurately the design characteristics of an ionization chamber and interpretation of measurements with it. The angular dependence analysis was carried out to validate the new concept for calculation of output current

  9. Ultrasound biomicroscopic features associated with angle closure in fellow eyes of acute primary angle closure after laser iridotomy.

    Science.gov (United States)

    Yao, Bao-qun; Wu, Ling-ling; Zhang, Chun; Wang, Xin

    2009-03-01

    To investigate the frequency of appositional angle closure and related anatomic characteristics in fellow eyes of Chinese subjects with acute primary angle closure (APAC) after laser peripheral iridotomy (LPI). Cross-sectional study. Consecutive subjects with APAC presenting from April 2006 to September 2006 at the Glaucoma Service of Peking University Eye Center, Peking University Third Hospital. Under dark conditions, fellow eyes were divided into 2 groups based on the detection of appositional angle closure by ultrasound biomicroscopy (UBM). For all subjects, UBM parameters were measured to evaluate the different anatomic features between the 2 groups. Darkroom provocative tests (DRPTs) and gonioscopy were performed to investigate the relationship between angle closure and intraocular pressure. Central anterior chamber depth (ACD); angle opening distance(500) (AOD(500)); angle recess area(750) (ARA(750)); trabecular-iris angle (T-I angle); trabecular-ciliary process distance (TCPD); peripheral iris thickness (IT(1)); iris-zonule distance (IZD); and the position of the iris insertion. Thirty-four post-LPI fellow eyes of 34 patients with APAC (8 men, 26 women; mean +/- standard deviation age 66.3+/-7.2 years, range 54-83) were included. Peripheral anterior synechiae (PAS) were not observed in any subject. Appositional angle closure was observed in at least 1 quadrant in 13 (38.2%) of the 34 patients. Compared with eyes without appositional closure, eyes with appositional closure showed significantly lower AOD(500), ARA(750), and T-I angle in 4 quadrants; shorter TCPD in the inferior and temporal quadrants; and thicker IT(1) in the superior and nasal quadrants (PAPAC showed appositional angle closure after LPI. The anatomic findings indicate a narrower angle, a more anterior position of the ciliary body, and a thicker peripheral iris in fellow eyes of APAC after LPI may be associated with an increased risk for progressive angle closure.

  10. Importância da velocidade do movimento celular na câmara anterior, na avaliação clínica das uveítes Importance of the speed of the cellular movement in the anterior chamber in the clinical evaluation of uveitis

    Directory of Open Access Journals (Sweden)

    Fernando Antônio L. Mendes Furtado

    2000-08-01

    Full Text Available Objetivo: Acrescentar ao oftalmologista mais um dado para avaliação clínica das uveítes, que acometem o segmento anterior; seja contribuindo para revelar a intensidade do processo inflamatório, seja ajudando a nortear a conduta terapêutica. Métodos: Estudamos 46 pacientes portadores de uveíte e com reação celular na câmara anterior. Observamos a velocidade do deslocamento das células no humor aquoso e a relacionamos com a intensidade do processo inflamatório, comparando com a sintomatologia e principais sinais clínicos. Resultados: Os resultados nos mostram que existe uma correlação direta entre a velocidade das células na câmara anterior e o grau de inflamação. Quanto mais grave a inflamação, menor é o deslocamento das células. E podemos aplicar esse fato na abordagem clínica das uveítes. Em algumas situações é mais fácil perceber alterações na velocidade que na quantidade de células ou flare. Conclusões: Nosso estudo apresenta um elemento novo na semiologia das uveítes, já que não encontramos referências na literatura médica. Familiarizando-se com a velocidade dos movimentos celulares na câmara anterior, podemos dispor de uma valioso recurso que nos ajude no exame do paciente com uveíte. Há casos em que a mudança na velocidade é o único elemento a nos indicar uma piora ou melhora do quadro clínico.Purpose: To add for the ophthalmologist an element for clinical evaluation of uveitis, affecting the anterior segment; contributing both to reveal the intensity of the inflammatory process and helping to guide the therapeutic management conduct. Methods: We studied 46 uveitis patients with cellular reaction in the anterior chamber. We observed the speed of the displacement of the cells in the aqueous humor and related it to the intensity of the inflammatory process, in comparison with the symptomatology and main clinical signs. Results: The results showed that there is an inverse correlation between the

  11. In vivo Confocal Microscopy of Posner-Schlossman Syndrome: Comparison with herpes simplex keratitis, HLA-B27 anterior uveitis and acute attack of primary angle closure.

    Science.gov (United States)

    Hong, Ying; Wang, Miao; Wu, Lingling

    2017-08-29

    To investigate in vivo confocal microscopy (IVCM) findings in patients with Posner-Schlossman Syndrome (PSS), we compared the IVCM findings from the eyes of patients with: PSS (44 eyes); herpes simplex keratitis (HSK) (45 eyes); HLA-B27 anterior uveitis (B27AU) (45 eyes); and with acute attack of primary angle closure (aPAC) (43 eyes). The central Langerhans cells (LCs) grade at the level of corneal basal epithelial cells of the PSS group (2.33 ± 0.55) was similar to that of the HSK group (2.63 ± 0.67) (χ 2  = -1.435, P = 0.174) but was significantly higher than those of the B27AU group (1.80 ± 0.79) (χ 2  = 2.311, P = 0.023) and the aPAC group (1.75 ± 0.46) (χ 2  = 2.701, P = 0.022). The keratocyte activation grade of the PSS group (1.55 ± 0.76) was similar to that of the HSK group (1.65 ± 0.81) (χ 2  = 1.104, P = 0.675) but was significantly higher than those of the B27AU group (1.00 ± 0.71) (χ 2  = 2.364, P = 0.025) and aPAC group (1.75 ± 0.46) (χ 2  = 2.532, P = 0.027). The LCs and keratocyte activation grades observed by IVCM in patients with PSS were higher than those in patients with B27AU and with aPAC, but they were similar to those in patients with HSK. This implies that PSS might be related to viral infection.

  12. Anterior Segment Tomography with the Cirrus Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Eduardo B. Rodrigues

    2012-01-01

    Full Text Available Optical coherence tomography (OCT is an optical acquisition method to examine biological tissues. In recent years, OCT has become an important imaging technology used in diagnosing and following macular pathologies. Further development enabled application of optical coherence tomography in evaluation of the integrity of the nerve fiber layer, optic nerve cupping, anterior chamber angle, or corneal topography. In this manuscript we overview the use of OCT in the clinical practice to enable corneal, iris, ciliary body, and angle evaluation and diagnostics.

  13. Diurnal Variation of Optical Coherence Tomography Measurements of Static and Dynamic Anterior Segment Parameters.

    Science.gov (United States)

    Xu, Benjamin Y; Penteado, Rafaella C; Weinreb, Robert N

    2018-01-01

    To examine the diurnal variation of static and dynamic anterior segment parameters in young, healthy eyes by comparing anterior segment optical coherence tomography (AS-OCT) measurements obtained in the morning and evening and also in the light and dark. Twenty-two subjects ranging from 19 to 47 years of age with no past ocular history were selected. Imaging was performed with the Tomey CASIA2 AS-OCT device in 2 fixed lighting environments, light and dark, between the hours of 08:30 to 10:00 and 17:30 to 19:00. Four AS-OCT images were analyzed per eye. Pupil diameter (PD), iris area (IA), iris curvature (IC), anterior chamber depth (ACD), lens vault (LV), anterior chamber width (ACW), anterior chamber area (ACA), angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), and trabecular iris angle (TIA) were measured. Pupil diameter was similar between the AM and PM groups in the light (P=0.89) and dark (P=0.51). There was no significant difference between AM and PM measurement values for any of the static or dynamic parameters in the light (P>0.39) and dark (P>0.31). Intraclass correlation coefficients (ICC) demonstrated excellent agreement between AM and PM measurement values in the light (ICC>0.81) and dark (ICC>0.93). In addition, there was no significant difference between AM and PM angle opening distance at 500 µm measurement values in the light (P>0.34) and dark (P>0.40) when each of 8 angle sectors was analyzed individually. No significant diurnal variation of static or dynamic anterior segment parameter measurements was detected in the light and dark. Diurnal variation of these parameters does not regularly occur in young, healthy eyes.

  14. Refraction and eye anterior segment parameters in schizophrenic patients

    Directory of Open Access Journals (Sweden)

    Tongabay Cumurcu

    2015-06-01

    Full Text Available ABSTRACT Purpose: To evaluate the difference in terms of refractive errors and anterior segment parameters between schizophrenic patients and healthy volunteers. Methods: This study compared 70 patients (48 men who were diagnosed with schizophrenia with a control group of 60 (35 men who were similar in terms of age, gender, education, and socioeconomic level. Anterior segment examination was performed using a Scheimflug system. Axial length and lens thickness (LT were measured using optic biometry. The following tests were administered to the psychiatric patient group: Brief Psychiatric Rating Scale (BPRS, Scale for the Assessment of Negative Symptoms (SANS, and Scale for the Assessment of Positive Symptoms (SAPS. Results: Mild myopia was detected in both the schizophrenic and control groups, with no statistically significant difference (p>0.005. Corneal volume (CV, anterior chamber volume (ACV, anterior chamber depth (ACD, and central corneal thickness (CCT values were lower in the schizophrenic group, and there was a statistically significant between-group difference (p=0.026, p=0.014, p=0.048, and p=0.005, respectively. LT was greater in schizophrenics, and the difference was found to be statistically significant (p=0.006. A statistically significant negative correlation was found between SAPS and cylinder values (p=0.008. The axial eye length, cylinder value, pupil diameter, mean keratometric value, and anterior chamber angle revealed no statistically significant difference between the groups (p>0.05. Conclusion: No statistically significant difference was detected in terms of refraction disorders between schizophrenics and the healthy control group, while some differences in anterior chamber parameters were present. These results demonstrate that schizophrenics may exhibit clinical and structural differences in the eye.

  15. Relationship between iris surface features and angle width in Asian eyes.

    Science.gov (United States)

    Sidhartha, Elizabeth; Nongpiur, Monisha Esther; Cheung, Carol Y; He, Mingguang; Wong, Tien Yin; Aung, Tin; Cheng, Ching-Yu

    2014-10-23

    To examine the associations between iris surface features with anterior chamber angle width in Asian eyes. In this prospective cross-sectional study, we recruited 600 subjects from a large population-based study, the Singapore Epidemiology of Eye Diseases (SEED) study. We obtained standardized digital slit-lamp iris photographs and graded the iris crypts (by number and size), furrows (by number and circumferential extent), and color (higher grade denoting darker iris). Vertical and horizontal cross-sections of anterior chamber were imaged using anterior segment optical coherence tomography. Angle opening distance (AOD), angle recess area (ARA), and trabecular-iris space area (TISA) were measured using customized software. Associations of the angle width with the iris surface features in the subject's right eyes were assessed using linear regression analysis. A total of 464 eyes of the 464 subjects (mean age: 57.5 ± 8.6 years) had complete and gradable data for crypts and color, and 423 eyes had gradable data for furrows. After adjustment for age, sex, ethnicity, pupil size, and corneal arcus, higher crypt grade was independently associated with wider AOD750 (β [change in angle width per grade higher] = 0.018, P = 0.023), ARA750 (β = 0.022, P = 0.049), and TISA750 (β = 0.011, P = 0.019), and darker iris was associated narrower ARA750 (β = -0.025, P = 0.044) and TISA750 (β = -0.013, P = 0.011). Iris surface features, assessed and measured from slit-lamp photographs, correlated well with anterior chamber angle width; irises with more crypts and lighter color were associated with wider angle. These findings may provide another imaging modality to assess angle closure risk based on iris surface features. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  16. Correlation between pupil diameter and angle configuration in the dark room provocative test.

    Science.gov (United States)

    Li, Dejiao; Wang, Ningli; Wang, Bingsong; Wang, Tao; Li, Shuning; Chen, Lijia; Mu, Dapeng

    2011-08-01

    To study the associations between changes in pupil diameter and in the anterior chamber angle configuration during the dark room provocative test. The study included 70 suspects of primary angle closure (study group) and 40 normal participants (control group). Using anterior-segment optical coherence tomography (AS-OCT), we measured the anterior chamber angle configuration and pupil diameter at 3 minutes and at 1.5 hours of dark adaptation. In the study group, the mean number of closed angle segments was significantly (Pdark adaptation (3.9 ± 2.3) than at room light conditions (2.6 ± 2.2) or at 1.5 hours of dark adaptation (3.1 ± 2.1), with no statistically significant (P>0.05) difference between the 2 latter values. In the study group, the pupil diameter was significantly associated with the number of closed angle segments at 3 minutes of dark adaptation (Pdark adaptation (P=0.13). Defined as an increased number of closed angle segments, the dark room test was positive in a significantly higher number of participants at 3 minutes than at 1.5 hours of dark adaptation [44 (63%) eyes vs. 31 (44%) eyes; Pdark adaptation (r2=0.21). After short-term dark adaptation of 3 minutes, the assessment of the anterior chamber angle configuration by AS-OCT is more reliable than as if carried out after a long-term dark adaptation and may be used to identify suspects of primary angle closure.

  17. Identifying anterior segment crystals.

    OpenAIRE

    Hurley, I W; Brooks, A M; Reinehr, D P; Grant, G B; Gillies, W E

    1991-01-01

    A series of 22 patients with crystals in the anterior segment of the eye was examined by specular microscopy. Of 10 patients with hypermature cataract and hyperrefringent bodies in the anterior chamber cholesterol crystals were identified in four patients and in six of the 10 in whom aspirate was obtained cholesterol crystals were demonstrated in three, two of these having shown crystals on specular microscopy. In 10 patients with intracorneal crystalline deposits, cholesterol crystals were f...

  18. Test chamber

    NARCIS (Netherlands)

    Leferink, Frank Bernardus Johannes

    1999-01-01

    A test chamber for measuring electromagnetic radiation emitted by an apparatus to be tested or for exposing an apparatus to be tested to an electromagnetic radiation field. The test chamber includes a reverberation chamber made of a conductive tent fabric. To create a statistically uniform field in

  19. Test chamber

    NARCIS (Netherlands)

    Leferink, Frank Bernardus Johannes

    2009-01-01

    A test chamber for measuring electromagnetic radiation emitted by an apparatus to be tested or for exposing an apparatus to be tested to an electromagnetic radiation field. The test chamber includes a reverberation chamber made of a conductive tent fabric. To create a statistically uniform field in

  20. Cluster headache or narrow angle glaucoma?

    Directory of Open Access Journals (Sweden)

    Prasad Palimar

    1991-01-01

    Full Text Available A 47 year old man with episodes of attacks of pain, redness and mild blurring of vision was investigated for narrow angle glaucoma in view of shallow anterior chambers and a cupped optic disc. The history was reviewed following a spontaneous attack in hospital, which had features other than acute glaucoma. A diagnosis of cluster headache was made on the basis of tests. Cluster headache has been defined as unilateral intense pain, involving the eye and head on one side, usually associated with flushing, nasal congestion and lacrimation; the attacks recurring one or more times daily and lasting 20 - 120 minutes. Such attacks commonly continue for weeks or months and are separated by an asymptomatic period of months to years. This episodic nature, together with unilaterality and tendency to occur at night, closely mimics narrow angle glaucoma. Further, if patients have shallow anterior chambers and disc cupping, the differentiation becomes more difficult yet critical. Resource to provocative tests is often the only answer as the following case report demonstrates.

  1. Anterior and posterior ocular biometry in healthy Chinese subjects: data based on AS-OCT and SS-OCT.

    Directory of Open Access Journals (Sweden)

    Wenbin Huang

    Full Text Available To measure the anterior and posterior ocular biometric characteristics concurrently and to determine the relationship between the iris and choroid in healthy Chinese subjects.A total of 148 subjects (270 eyes were enrolled in this cross-section study. The anterior and posterior ocular biometric characteristics were measured simultaneously by anterior segment optical coherence tomography (AS-OCT and swept-source optical coherence tomography (SS-OCT.Compared with male eyes, female eyes had narrower anterior biometric parameters that presented with smaller anterior segment parameters [including anterior chamber depth (ACD, width (ACW, area (ACA, and volume (ACV; (all p<0.001], narrower anterior chamber angle parameters [including angle opening distance (AOD750, trabecular-iris space area (TISA750, and angle recess area (ARA; (all p<0.001], higher iris curvature (ICURV (p = 0.003, and larger lens vaults (LV (p = 0.019. These anterior ocular biometric parameters were correlated with increasing age (p<0.01. Iris thickness (IT750 and iris area (IAREA were associated with age, ACW, and pupil diameter (all p<0.05, while choroidal thickness (CT was associated with age, gender, and axial length (all p<0.05. Univariate regression analysis showed that greater CT was significantly associated with smaller IAREA (p = 0.026.Compared with male eyes, female eyes had narrower anterior biometric parameters that correlated with increasing age, which would be helpful in explaining the higher prevalence of angle closure rates in the female gender and in aging people. Increased CT might be associated with smaller iris area; however, this possibility needs to be investigated in future studies before this conclusion is made.

  2. Ocular biometry in angle closure.

    Science.gov (United States)

    Razeghinejad, Mohammad Reza; Banifatemi, Mohammad

    2013-01-01

    To compare ocular biometric parameters in primary angle closure suspects (PACS), primary angle closure glaucoma (PACG) and acute primary angle closure (APAC). This cross-sectional study was performed on 113 patients including 33 cases of PACS, 45 patients with PACG and 35 subjects with APAC. Central corneal thickness (CCT), axial length (AL), anterior chamber depth (ACD) and lens thickness (LT) were measured with an ultrasonic biometer. Lens-axial length factor (LAF), relative lens position, corrected ACD (CACD) and corrected lens position were calculated. The parameters were measured bilaterally but only data from the right eyes were compared. In the APAC group, biometric parameters were also compared between affected and unaffected fellow eyes. Logistic regression analysis was performed to identify risk factors. No statistically significant difference was observed in biometric parameters between PACS and PACG eyes, or between affected and fellow eyes in the APAC group (P>0.05 for all comparisons). However, eyes with APAC had thicker cornea (P=0.001), thicker lens (PAPAC. In the APAC group, LAF (PAPAC.

  3. Comparison of Incisor, Molar and Anterior Facial Height in Normal, Angle Class II Division 1 and Class III Malocclusion: A Cephalometric Study

    Directory of Open Access Journals (Sweden)

    A M Deoghare

    2012-01-01

    Results: After studying specific landmarks and planes in the cephalograms, it was concluded that anterior facial height is significantly small in Class II Div 1, compared to normal and Class III. A fair degree of constancy of upper and lower face heights has been found in the study. It was also found that the upper molar height is contributory to increase and decrease in vertical proportions of face. Lower molar height can be related to the degree of overbite in Class II Div 1 case.

  4. Difference of uveal parameters between the acute primary angle closure eyes and the fellow eyes.

    Science.gov (United States)

    Li, Xingyi; Wang, Wei; Huang, Wenbin; Chen, Shida; Wang, Jiawei; Wang, Zhonghao; Liu, Yaoming; He, Mingguang; Zhang, Xiulan

    2018-03-01

    To measure the anterior and posterior ocular biometric characteristics concurrently and to explore the relationship between iris, ciliary body and choroid in acute primary angle closure eyes (APAC) and fellow eyes. It is a prospective, cross-sectional study. Thirty patients with recent APAC were finally enroled in it. Anterior and posterior uveal parameters were measured simultaneously by anterior segment optical coherence tomography (AS-OCT), swept-source optical coherence tomography (SS-OCT) and ultrasound biomicroscopy (UBM). The parameters were measured including: pupil diameter (PD); iris thickness, curvature (ICURV), area (IAREA); anterior chamber depth (ACD), width (ACW), area (ACA), volume (ACV); lens vault (LV); choroidal thickness and retinal thickness; maximum ciliary body thickness (CBTmax); ciliary body thickness at the point of the scleral spur (CBT0) and 1000 mm away (CBT1000); anterior placement of the ciliary body (APCB); and trabecular-ciliary angle (TCA). Compared with fellow eyes, APAC eyes had narrower anterior biometric parameters and presented with smaller anterior segment parameters (including ACD and ACW); (p APAC eyes had narrower anterior biometric parameters, thinner ciliary body and smaller iris area and curvature. APCB, CBT and choroidal thickness were positively correlated. However, further studies are required before these conclusions are generalised.

  5. Cloud Chamber

    DEFF Research Database (Denmark)

    Gfader, Verina

    Cloud Chamber takes its roots in a performance project, titled The Guests 做东, devised by Verina Gfader for the 11th Shanghai Biennale, ‘Why Not Ask Again: Arguments, Counter-arguments, and Stories’. Departing from the inclusion of the biennale audience to write a future folk tale, Cloud Chamber...

  6. wire chamber

    CERN Multimedia

    Proportional multi-wire chamber. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle. Proportional wire chambers allow a much quicker reading than the optical or magnetoscriptive readout wire chambers.

  7. Effects of 1% cyclopentolate hydrochloride on anterior segment parameters obtained with Pentacam in young adults

    Directory of Open Access Journals (Sweden)

    Ceyhun Arici

    2014-08-01

    Full Text Available Purpose: To investigate the effects of topically applied 1% cyclopentolate hydrochloride on anterior segment parameters obtained with a Pentacam rotating Scheimpflug camera in healthy young adults. Methods: Anterior segment analyses of 25 eyes from 25 young adults (Group 1, before and after 45 min of 1% cyclopentolate hydrochloride application, were performed. For a control group (cycloplegia-free, Group 2, 24 eyes of 24 age- and sex-matched healthy cases were evaluated twice at 45 min intervals. The results obtained from the groups were compared statistically. Results: The mean ages of the groups were 23.04 ± 3.42 (range, 18-29 and 22.4 ± 2.05 (range, 18-27 years for Groups 1 and 2, respectively (p=0.259. In Group 1, measurements between the two analyses were significantly different for the values of anterior chamber depth (ACD, anterior chamber angle (ACA, and anterior chamber volume (ACV (p<0.05, whereas no statistical difference was found for the central corneal thickness (CCT and keratometry (K1, K2 measurements. In Group 2, none of these parameters were statistically different between the two analyses. Conclusions: Topically applied 1% cyclopentolate hydrochloride caused an increase in the ACD and ACV values, and a decrease in the ACA value. However, it had no significant effect on the CCT and keratometry measurements. It is important to consider these effects when using the Pentacam device on young adults with cycloplegia and when applying it for various reasons.

  8. Evaluation of anterior segment parameters in patients with pseudoexfoliation syndrome using Scheimpflug imaging

    Directory of Open Access Journals (Sweden)

    Alime Gunes

    2016-06-01

    Full Text Available ABSTRACT Purpose: To evaluate anterior segment parameters in patients with pseudoexfoliation syndrome (PXS using Scheimpflug imaging. Methods: Forty-three PXS patients and 43 healthy control subjects were included in this cross-sectional study. All participants underwent a detailed ophthalmologic examination. Anterior segment parameters were measured using a Scheimpflug system. Results: Considering the PXS and control groups, the mean corneal thicknesses at the apex point (536 ± 31 and 560 ± 31 µm, respectively, p=0.001, at the center of the pupil (534 ± 31 and 558 ± 33 µm, respectively, p=0.001, and at the thinnest point (528 ± 30 and 546 ± 27 µm, respectively, p=0.005 were significantly thinner in PXS patients. Visual acuity was significantly lower (0.52 ± 0.37 versus 0.88 ± 0.23, p<0.001 and axial length was significantly longer (23.9 ± 0.70 mm versus 23.2 ± 0.90 mm, p=0.001 in the PXS eyes than in the control eyes. There were no statistically significant differences in the mean values of keratometry, anterior chamber angle, anterior chamber depth, corneal volume, and anterior chamber volume between the PXS and control eyes. Conclusions: The patients with PXS had thinner corneas, worse visual acuity, and longer axial length compared with those in the healthy controls.

  9. Small-incision cataract extraction combined trabeculectomy for primary angle-closure glaucoma with cataract

    Directory of Open Access Journals (Sweden)

    Yu-Feng Wu

    2014-09-01

    Full Text Available AIM: To observe the curative effect of treating small-incision cataract extraction by intraocular lens implantation combined with trabeculectomy for primary angle-closure glaucoma with cataract. METHODS: Totally 44 cases(52 eyesof primary angle-closure glaucoma combined with cataract were selected to undergo the combined surgery, in order to observe the patients' pre- and postoperative eyesights, intraocular pressures and the postoperative complications.RESULTS: The postoperative eyesight was improved significantly as compared with the preoperative eyesight. The intraocular pressure was declined dramatically. The result was of statistical significance(P0.05. All the 52 cases' surgeries were performed by the same surgeon. The surgeries were processed smoothly, with 6 postoperative eyes of anterior chamber inflammation cell response, 3 eyes of anterior chamber fibrinoid exudate, 2 eyes of shallow anterior chamber through mydriasis and treatment with glucocorticoids and non-steroidal eyedrops before absorption, and no complications like malignant glaucoma, cyclodialysis, etc. were reported through mydriasis and pressure bandaging before recovery.CONCLUSION: Treating the primary angle-closure glaucoma combined with cataract through the combined surgery has high reliability and desirable curative effect. The surgical method is simple to learn and applicable for promotion on the basic level.

  10. Assessment of anterior segment parameters under photopic and scotopic conditions in Indian eyes using anterior segment optical coherence tomography

    Directory of Open Access Journals (Sweden)

    Dacosta Shaun

    2008-01-01

    Full Text Available Purpose: To compare the anterior segment parameters in photopic and scotopic conditions using anterior segment optical coherence tomography (AS OCT in Indian eyes. Materials and Methods: One hundred eyes of 100 normal subjects of both sexes, aged 19 to 76 years, underwent anterior segment evaluation by AS OCT (VisanteTM OCT. Central corneal thickness (CCT, central anterior chamber depth (ACD, pupil diameter (PD and the temporal and nasal peripheral irido-corneal angles were assessed in photopic and scotopic conditions. These anterior segment parameters were stratified for age, sex and refractive error. Results: Mean values of the parameters measured in photopic and scotopic conditions respectively were as follows: ACD (mm 2.88 ± 0.32, 2.89 ± 0.32 (P = 0.10; nasal angle (degrees 28.80 ± 5.91, 22.28 ± 7.50 (P < 0.001; temporal angle (degrees 29.95 ± 6.74, 22.82 ± 8.43 (P < 0.001; pupil diameter (mm 4.08 ± 0.91, 4.68 ± 0.92 (P < 0.001; CCT (µm 519 ± 33.88, 519 ± 33.88. Conclusions: There was no significant difference in the ACD in photopic and scotopic conditions. While the nasal and temporal angles showed a significant decrease, the pupil diameter showed a significant increase in scotopic conditions. Mean central ACD decreased with age and was shallower in females than in males. It was highest in myopes and lowest in hypermetropes. CCT was not influenced by photopic and scotopic conditions.

  11. Wire Chamber

    CERN Multimedia

    Magnetoscriptive readout wire chamber. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  12. Wire chamber

    CERN Multimedia

    1967-01-01

    Magnetoscriptive readout wire chamber.Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  13. Ionization chambers

    International Nuclear Information System (INIS)

    Boag, J.W.

    1987-01-01

    Although a variety of solid-state and chemical methods for measuring radiation dose have been developed in recent decades and calorimetry can now provide an absolute standard of reference, ionization dosimetry retains its position as the most widely used, most convenient, and, in most situations, most accurate method of measuring either exposure or absorbed dose. The ionization chamber itself is the central element in this system of dosimetry. In this chapter the principles governing the construction and operation of ionization chambers of various types are examined. Since the ionization chambers now in general use are nearly all of commercial manufacture, the emphasis is on operating characteristics and interpretation of measurements rather than on details of construction, although some knowledge of the latter is often required when applying necessary corrections to the measured quantities. Examples are given of the construction of typical chambers designed for particular purposes, and the methods of calibrating them are discussed

  14. Nonsurgical correction of a severe anterior deep overbite accompanied by a gummy smile and posterior scissor bite using a miniscrew-assisted straight-wire technique in an adult high-angle case.

    Science.gov (United States)

    Wang, Xue-Dong; Zhang, Jie-Ni; Liu, Da-Wei; Lei, Fei-Fei; Zhou, Yan-Heng

    2016-07-01

    In the present report, we describe the successful use of miniscrews to achieve vertical control in combination with the conventional sliding MBT™ straight-wire technique for the treatment of a 26-year-old Chinese woman with a very high mandibular plane angle, deep overbite, retrognathic mandible with backward rotation, prognathic maxilla, and gummy smile. The patient exhibited skeletal Class II malocclusion. Orthodontic miniscrews were placed in the maxillary anterior and posterior segments to provide rigid anchorage and vertical control through intrusion of the incisors and molars. Intrusion and torque control of the maxillary incisors relieved the deep overbite and corrected the gummy smile, while intrusion of the maxillary molars aided in counterclockwise rotation of the mandibular plane, which consequently resulted in an improved facial profile. After 3.5 years of retention, we observed a stable, well-aligned dentition with ideal intercuspation and more harmonious facial contours. Thus, we were able to achieve a satisfactory occlusion, a significantly improved facial profile, and an attractive smile for this patient. The findings from this case suggest that nonsurgical correction using miniscrew anchorage is an effective approach for camouflage treatment of high-angle cases with skeletal Class II malocclusion.

  15. Target Chamber Manipulator

    Science.gov (United States)

    Tantillo, Anthony; Watson, Matthew

    2015-11-01

    A system has been developed to allow remote actuation of sensors in a high vacuum target chamber used with a particle accelerator. Typically, sensors of various types are placed into the target chamber at specific radial and angular positions relative to the beam line and target. The chamber is then evacuated and the experiments are performed for those sensor positions. Then, the chamber is opened, the sensors are repositioned to new angles or radii, and the process is repeated, with a separate pump-down cycle for each set of sensor positions. The new sensor positioning system allows scientists to pre-set the radii of up to a dozen sensors, and then remotely actuate their angular positions without breaking the vacuum of the target chamber. This reduces the time required to reposition sensors from 6 hours to 1 minute. The sensors are placed into one of two tracks that are separately actuated using vacuum-grade stepping motors. The positions of the sensors are verified using absolute optical rotary encoders, and the positions are accurate to 0.5 degrees. The positions of the sensors are electronically recorded and time-stamped after every change. User control is through a GUI using LabVIEW.

  16. Postiridotomy ultrasound biomicroscopy features in the fellow eye of Chinese patients with acute primary angle-closure and chronic primary angle-closure glaucoma.

    Science.gov (United States)

    Chen, Hui-Jin; Wang, Xin; Yan, Yu-Jie; Wu, Ling-Ling

    2015-03-01

    To compare the features of postiridotomy ultrasound biomicroscopy (UBM) in Chinese patients with acute primary angle-closure (aPAC) and with chronic primary angle-closure (cPAC) glaucoma. Consecutive cases were classified into acute and chronic groups. The acute group included 77 patients with unilateral aPAC. The chronic group included 57 patients with unilateral advanced cPAC glaucoma. In both the groups, the patients' fellow eye underwent a laser iridotomy and was studied. The main outcome measures included qualitative UBM parameters such as a plateau iris, anterior iris insertion, and an anteriorly rotated ciliary process and quantitative UBM parameters such as central anterior chamber depth (ACD), basal iris thickness (IT500), and scleral ciliary process angle (SCPA). For the qualitative parameters, more eyes in the chronic group had a plateau iris (P=0.046), an anterior iris insertion (P=0.222), and an anteriorly rotated ciliary process (P=0.090) than those in the acute group. For the quantitative parameters, the eyes in the chronic group had a deeper ACD (PaPAC may have a shallower ACD. For Chinese patients, a nonpupillary block component may play a more important role in asymptomatic cPAC than in aPAC.

  17. Plateau iris in Japanese patients with primary angle closure and primary angle closure glaucoma.

    Science.gov (United States)

    Mizoguchi, Takanori; Ozaki, Mineo; Wakiyama, Harumi; Ogino, Nobuchika

    2015-01-01

    To determine the prevalence of plateau iris in Japanese patients with primary angle closure (PAC) and primary angle closure glaucoma (PACG) and analyze the biometric parameters in patients with plateau iris using ultrasound biomicroscopy (UBM). In this cross-sectional observational study, subjects aged >50 years with PAC and PACG who had previously undergone a patent laser peripheral iridotomy underwent UBM in one eye. UBM images were qualitatively analyzed using standardized criteria. Plateau iris in a quadrant was defined by anteriorly directed ciliary body, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact. At least two quadrants had to fulfill these UBM criteria for an eye to be classified as having plateau iris. A-scan biometry was used to measure anterior segment parameters. Ninety-one subjects with PAC (58 subjects) or PACG (33 subjects) and 68 normal controls were recruited. The mean (standard deviation) ages of PAC and PACG patients and normal controls were 73.5 (6.2) and 72.6 (7.3), respectively. Based on UBM criteria, plateau iris was found in 16 eyes (17.6%) of 91 eyes. In these 16 eyes, quadrant-wise analysis showed ten eyes (62.5%) had plateau iris in two quadrants; four eyes (25%) had plateau iris in three quadrants; and two eyes (12.5%) had plateau iris in four quadrants. Anterior chamber depth, lens thickness, axial length, lens position, and relative lens position were not statistically significant between the group having plateau iris and that not having plateau iris, respectively. Approximately 20% of Japanese subjects with PAC and PACG with a patent laser peripheral iridotomy were found to have plateau iris on UBM. No morphological difference was noted in the anterior segment of the eye between those with or without plateau iris.

  18. Reverse pupillary block after implantation of a scleral-sutured posterior chamber intraocular lens: a retrospective, open study.

    Science.gov (United States)

    Bang, Seung Pil; Joo, Choun-Ki; Jun, Jong Hwa

    2017-03-29

    To report the clinical features of patients with reverse pupillary block (RPB) after scleral-sutured posterior chamber intraocular lens (PC IOL) implantation and biometric changes after laser peripheral iridotomy (LPI). Eight patients attending our hospital's ophthalmology outpatient clinic, who developed RPB after implantation of a scleral-sutured PC IOL due to subluxation of the crystalline lens or IOL, were investigated in this retrospective, observational study. Preoperative evaluations showed angle pigmentation in all cases and iridodonesis in 2 cases. Two subjects had used an α 1A -adrenoceptor antagonist for benign prostatic hyperplasia. Pars plana or anterior partial vitrectomy was performed in all cases. All eyes showed an extremely deep anterior chamber, a concave iris configuration, and contact between the IOL optic and the iris at the pupillary margin. Pupil capture was detected in 2 cases. The mean (± SD) anterior chamber angle (ACA) was 89.91 ± 10.06°, and the anterior chamber depth (ACD) was 4.42 ± 0.16 mm before LPI. After LPI, the iris immediately became flat with a decreased ACA (51.70 ± 2.59°; P = 0.018) and ACD (4.14 ± 0.15 mm; P = 0.012). After LPI, the intraocular pressure decreased from 19.75 ± 3.77 mmHg to 15.63 ± 4.30 mmHg (P = 0.011), and the spherical equivalent decreased from -0.643 ± 0.385 D to - 0.875 ± 0.505 D (P = 0.016). Concomitant vitrectomy, angle pigmentation, and iridodonesis may be risk factors for RPB after scleral-sutured PC IOL implantation. LPI is effective for relieving the RPB.

  19. Angle parameter changes of phacoemulsification and combined phacotrabeculectomy for acute primary angle closure

    Directory of Open Access Journals (Sweden)

    Shi-Wei Li

    2015-08-01

    Full Text Available AIM: To evaluate the difference in angle parameters and clinical outcome following phacoemulsification and combined phacotrabeculectomy in patients with acute primary angle closure (APAC using ultrasound biomicroscopy (UBM.METHODS: Patients (n=23, 31 eyes were randomized to receive phacoemulsification or combined phacotrabeculectomy (n=24, 31 eyes. Best-corrected visual acuity (BCVA, intraocular pressure (IOP, the main complications following surgery, and indentation gonioscopy and angle parameters measured using UBM were documented preoperatively and postoperatively.RESULTS:The improvement in BCVA in the phacoemulsification group was significantly greater than in the combined group (P<0.05. IOP in the phacoemulsification group was slightly higher than in the combined group following 1wk of follow-up (P<0.05, whereas there was no significant difference between the two groups at the latter follow-up (P>0.05. Phacoemulsification alone resulted in a slight increase in the trabecular ciliary processes distance compared with the combined surgery (P<0.05, whereas the other angle parameters showed no significant difference between the groups. Complications in combined group were greater than phacoemulsification only group.CONCLUSION:Both surgeries effectively opened the drainage angle and deepened the anterior chamber, and IOP was well controlled postoperatively. However, phacoemulsification showed better efficacy in improving visual function and showed reduced complications following surgery.

  20. wire chamber

    CERN Multimedia

    Was used in ISR (Intersecting Storage Ring) split field magnet experiment. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  1. Wire chamber

    CERN Multimedia

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  2. wire chamber

    CERN Multimedia

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  3. wire chamber

    CERN Multimedia

    1985-01-01

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  4. Robert Chambers

    NARCIS (Netherlands)

    K. Biekart (Kees); D.R. Gasper (Des)

    2013-01-01

    textabstractProfessor Robert Chambers is a Research Associate at the Institute of Development Studies (IDS), University of Sussex (Brighton, UK), where he has been based for the last 40 years, including as Professorial Research Fellow. He became involved in the field of development management in the

  5. Development of a large position-sensitive gas ionization chamber

    International Nuclear Information System (INIS)

    Adler, L.; Rogers, R.

    1977-01-01

    The basic design of a position-sensitive gas ionization chamber is described. It spans an angle of 97 0 and fits inside at 15'' radius scattering chamber. Construction features and preliminary performance data are discussed. 2 figures, 1 table

  6. Ocular Biometry in Angle Closure

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Razeghinejad

    2013-01-01

    Full Text Available Purpose: To compare ocular biometric parameters in primary angle closure suspects (PACS, primary angle closure glaucoma (PACG and acute primary angle closure (APAC. Methods: This cross-sectional study was performed on 113 patients including 33 cases of PACS, 45 patients with PACG and 35 subjects with APAC. Central corneal thickness (CCT, axial length (AL, anterior chamber depth (ACD and lens thickness (LT were measured with an ultrasonic biometer. Lens-axial length factor (LAF, relative lens position, corrected ACD (CACD and corrected lens position were calculated. The parameters were measured bilaterally but only data from the right eyes were compared. In the APAC group, biometric parameters were also compared between affected and unaffected fellow eyes. Logistic regression analysis was performed to identify risk factors. Results: No statistically significant difference was observed in biometric parameters between PACS and PACG eyes, or between affected and fellow eyes in the APAC group (P>0.05 for all comparisons. However, eyes with APAC had thicker cornea (P=0.001, thicker lens (P<0.0001, shallower ACD (P=0.009, shallower CACD (P=0.003 and larger LAF (P<0.0001. Based on ROC curve analysis, lower ACD, and larger LT, LAF and CCT values were associated with APAC. In the APAC group, LAF (P<0.0001 and CCT (P=0.001 were significant risk factors. Conclusion: This study revealed no significant difference in biometric characteristics in eyes with PACS and PACG. However, larger LAF and CCT were predictive of APAC.

  7. Agreement between Gonioscopic Examination and Swept Source Fourier Domain Anterior Segment Optical Coherence Tomography Imaging

    Directory of Open Access Journals (Sweden)

    Mohammed Rigi

    2016-01-01

    Full Text Available Purpose. To evaluate interobserver, intervisit, and interinstrument agreements for gonioscopy and Fourier domain anterior segment optical coherence tomography (FD ASOCT for classifying open and narrow angle eyes. Methods. Eighty-six eyes with open or narrow anterior chamber angles were included. The superior angle was classified open or narrow by 2 of 5 glaucoma specialists using gonioscopy and imaged by FD ASOCT in the dark. The superior angle of each FD ASOCT image was graded as open or narrow by 2 masked readers. The same procedures were repeated within 6 months. Kappas for interobserver and intervisit agreements for each instrument and interinstrument agreements were calculated. Results. The mean age was 50.9 (±18.4 years. Interobserver agreements were moderate to good for both gonioscopy (0.57 and 0.69 and FD ASOCT (0.58 and 0.75. Intervisit agreements were moderate to excellent for both gonioscopy (0.53 to 0.86 and FD ASOCT (0.57 and 0.85. Interinstrument agreements were fair to good (0.34 to 0.63, with FD ASOCT classifying more angles as narrow than gonioscopy. Conclusions. Both gonioscopy and FD ASOCT examiners were internally consistent with similar interobserver and intervisit agreements for angle classification. Agreement between instruments was fair to good, with FD ASOCT classifying more angles as narrow than gonioscopy.

  8. Anterior and posterior ocular biometry in healthy Chinese subjects: data based on AS-OCT and SS-OCT.

    Science.gov (United States)

    Huang, Wenbin; Gao, Xinbo; Li, Xingyi; Wang, Jiawei; Chen, Shida; Wang, Wei; Du, Shaolin; He, Mingguang; Zhang, Xiulan

    2015-01-01

    To measure the anterior and posterior ocular biometric characteristics concurrently and to determine the relationship between the iris and choroid in healthy Chinese subjects. A total of 148 subjects (270 eyes) were enrolled in this cross-section study. The anterior and posterior ocular biometric characteristics were measured simultaneously by anterior segment optical coherence tomography (AS-OCT) and swept-source optical coherence tomography (SS-OCT). Compared with male eyes, female eyes had narrower anterior biometric parameters that presented with smaller anterior segment parameters [including anterior chamber depth (ACD), width (ACW), area (ACA), and volume (ACV); (all piris space area (TISA750), and angle recess area (ARA); (all piris curvature (ICURV) (p = 0.003), and larger lens vaults (LV) (p = 0.019). These anterior ocular biometric parameters were correlated with increasing age (pIris thickness (IT750) and iris area (IAREA) were associated with age, ACW, and pupil diameter (all pbiometric parameters that correlated with increasing age, which would be helpful in explaining the higher prevalence of angle closure rates in the female gender and in aging people. Increased CT might be associated with smaller iris area; however, this possibility needs to be investigated in future studies before this conclusion is made.

  9. The change of anterior segment parameters after cataract surgery in normal-tension glaucoma

    Directory of Open Access Journals (Sweden)

    Wonseok Lee

    2017-08-01

    Full Text Available AIM: To investigate the change of anterior chamber angle morphology and intraocular pressure (IOP reduction after cataract surgery in patients with normal-tension glaucoma (NTG using swept-source optical coherence tomography (SS-OCT. METHODS: This prospective, comparative, observational study recruited patients into two groups. Group 1 was the control group including normal subjects except those with cataracts (cataract group, n=67 eyes of 67 patients, and group 2 was NTG group including patients who were diagnosed with NTG and cataracts (n=43 eyes of 43 patients, which were treated with phacoemulsification and intraocular lens implantation. Before surgery, and at postoperative 1 and 6mo, anterior chamber angles were evaluated by SS-OCT under dark conditions using three-dimensional angle analysis scan protocol. Angle opening distance (AOD, angle recess area (ARA, and trabecular-iris surface area (TISA at four quadrants (temporal, nasal, superior, and inferior were calculated automatically by SS-OCT, after the observer marked scleral spurs. RESULTS: A total of 106 patients (54 males and 52 females were enrolled in the study. Angle parameters, AOD, ARA, and TISA were increased after surgery in both groups. However, changes of angle parameters were only significant in group 2. In group 2, preoperative IOP was 13.2±2.9 mm Hg, and postoperative IOP at 1 and 6mo were 10.5±3.0 and 10.7±2.8 mm Hg, respectively. In group 1, preoperative IOP was 12.4±2.8 mm Hg, and postoperative IOP at 1 and 6mo were 11.6±2.5 and 12.0±2.8 mm Hg, respectively. After cataract surgery, angle parameters changed significantly while IOP significantly reduced and was maintained in group 2 (P<0.001. The changes in angle parameters (ΔAOD500, ΔTISA500 at temporal; ΔAOD500, ΔARA500 at nasal were linearly correlated with postoperative IOP changes. CONCLUSION: Cataract surgery may have improved anterior chamber angle parameters and decreased IOP in NTG patients.

  10. Suppression chamber

    International Nuclear Information System (INIS)

    Goto, Hiroshi; Tsuji, Akio.

    1976-01-01

    Purpose: To miniaturize the storage tank of condensated water in BWR reactor. Constitution: A diaphragm is provided in a suppression chamber thereby to partition the same into an inner compartment and an outer compartment. In one of said compartments there is stored clean water to be used for feeding at the time of separating the reactor and for the core spray system, and in another compartment there is stored water necessary for accomplishing the depressurization effect at the time of coolant loss accident. To the compartment in which clean water is stored there is connected a water cleaning device for constantly maintaining water in clean state. As this cleaning device an already used fuel pool cleaning device can be utilized. Further, downcomers for accomplishing the depressurization function are provided in both inner compartment and outer compartment. The capacity of the storage tank can be reduced by the capacity of clean water within the suppression chamber. (Ikeda, J.)

  11. Plateau iris in Japanese patients with primary angle closure and primary angle closure glaucoma

    Directory of Open Access Journals (Sweden)

    Mizoguchi T

    2015-06-01

    Full Text Available Takanori Mizoguchi,1 Mineo Ozaki,2,3 Harumi Wakiyama,1,4 Nobuchika Ogino1,51Mizoguchi Eye Clinic, Nagasaki, Japan; 2Ozaki Eye Clinic Miyazaki, Japan; 3Department of Ophthalmology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan; 4The Japanese Red Cross Nagasaki Genbaku Hospital, Nagasaki, Japan; 5Nishigaki Eye Clinic, Nagoya, JapanPurpose: To determine the prevalence of plateau iris in Japanese patients with primary angle closure (PAC and primary angle closure glaucoma (PACG and analyze the biometric parameters in patients with plateau iris using ultrasound biomicroscopy (UBM.Methods: In this cross-sectional observational study, subjects aged >50 years with PAC and PACG who had previously undergone a patent laser peripheral iridotomy underwent UBM in one eye. UBM images were qualitatively analyzed using standardized criteria. Plateau iris in a quadrant was defined by anteriorly directed ciliary body, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact. At least two quadrants had to fulfill these UBM criteria for an eye to be classified as having plateau iris. A-scan biometry was used to measure anterior segment parameters.Results: Ninety-one subjects with PAC (58 subjects or PACG (33 subjects and 68 normal controls were recruited. The mean (standard deviation ages of PAC and PACG patients and normal controls were 73.5 (6.2 and 72.6 (7.3, respectively. Based on UBM criteria, plateau iris was found in 16 eyes (17.6% of 91 eyes. In these 16 eyes, quadrant-wise analysis showed ten eyes (62.5% had plateau iris in two quadrants; four eyes (25% had plateau iris in three quadrants; and two eyes (12.5% had plateau iris in four quadrants. Anterior chamber depth, lens thickness, axial length, lens position, and relative lens position were not statistically significant between the group having plateau iris and that not having plateau iris

  12. O comprimento dos túneis femorais varia com a flexão do joelho na reconstrução anatômica do ligamento cruzado anterior Femoral tunnels' length changes with knee flexion angle in anatomical anterior cruciate ligament reconstruction

    Directory of Open Access Journals (Sweden)

    Julio Cesar Gali

    2012-04-01

    Full Text Available OBJETIVO: O propósito de nosso trabalho foi avaliar o efeito que o grau de flexão do joelho, durante a perfuração dos túneis femorais, pode causar no comprimento desses túneis, na reconstrução anatômica do ligamento cruzado anterior. MÉTODOS: Medimos o comprimento dos túneis femorais anteromedial e posterolateral do ligamento cruzado anterior, em 20 peças anatômicas de joelhos desemparelhadas, 10 direitas e 10 esquerdas, todas com a cartilagem e ligamentos cruzados íntegros. Os túneis foram perfurados com os joelhos flexionados a 90, 110 e 130 graus de flexão, através do portal anteromedial acessório, com uma broca de 2,5mm. Os estudos estatísticos foram realizadas pela análise de variância de Friedman e pelo teste de Mann-Whitney. RESULTADO: A média dos comprimentos dos túneis femorais anteromediais medidos com os joelhos flexionados a 90, 110 e 130 graus foram 33,7 ± 3,72mm, 37,4 ± 2,93mm e 38,8 ± 3,31mm, respectivamente. Para o comprimento dos túneis posterolaterais, os resultados obtidos a 90, 110 e 130 graus foram 32,1 ± 4,24mm, 37,3 ± 4,85mm e 38,4 ± 2,51mm, respectivamente. A análise de variância de Friedman mostrou diferença significativa entre os comprimentos dos túneis perfurados com 90 e 110 graus de flexão das peças, porém não mostrou diferença significativa entre os obtidos com flexão de 110e 130 graus (p OBJECTIVE: The objective of our study was to evaluate the effect that knee flexion angle while femoral tunnels are being drilled may have on the length of these tunnels, in anatomical reconstruction of the anterior cruciate ligament. METHODS: We measured the lengths of anteromedial and posterolateral tunnels for the anterior cruciate ligament in 20 unpaired anatomical knee specimens (10 right and 10 left knees, all with the cartilage and cruciate ligaments intact. Tunnels were drilled with the knees flexed at 90º, 110º and 130º, through the accessory anteromedial portal, with a 2.5 mm

  13. Toxic anterior segment syndrome following deep anterior lamellar keratoplasty

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    Neslihan Sevimli

    Full Text Available ABSTRACT We present the case of a 31-year-old patient with toxic anterior segment syndrome (TASS that developed after undergoing deep anterior lamellar keratoplasty (DALK. She had keratoconus, and despite wearing hard contact lenses for many years in the left eye, her vision had deteriorated; therefore, DALK was performed on this eye. The preoperative visual acuity (VA was finger counting at 3 m. Routine DALK was performed using the "big-bubble" technique. The corneal entry incision was hydrated at the end of the surgery, which was terminated by air injection into the anterior chamber. On postoperative day 1, VA was at the level of hand movements, and the cornea was edematous. Topical high-dose dexamethasone and oral steroids were initiated considering the diagnosis of TASS. Subsequently, the patient's VA increased, and the corneal edema decreased. We believe that the use of re-sterilized cannulas may have been the likely cause of TASS. Although DALK can be performed without interfering with the anterior chamber, one should keep in mind that TASS may occur in response to the solution used to hydrate the incision site and the air injected into the anterior chamber.

  14. EFFECTS OF FLUNIXIN MEGLUMINE CONJUNCTIVAL SHOT OVER THE HUMOR AQUEOUS PROTEIN OF DOGS SUBMITTED TO THE PARACENTESIS OF THE ANTERIOR CHAMBER AVALIAÇÃO DOS EFEITOS DA FLUNIXINA MEGLUMINA, POR VIA SUBCONJUNTIVAL, SOBRE A CONCENTRAÇÃO E PADRÃO PROTEICO DO HUMOR AQUOSO DE CÃES SUBMETIDOS À PARACENTESE DA CÂMARA ANTERIOR

    Directory of Open Access Journals (Sweden)

    Paula Diniz Galera

    2009-12-01

    Full Text Available

    Flunixin meglumine effects, over aqueous humor proteins of eyes on dogs who were submitted to paracentesis of the anterior chamber, were evaluated. To ten adult dogs clinically healthy were given a subconjunctival shot with flunixin meglumine (1.1mg/Kg on the right eye and sterilized saline solution 0.9% on the left eye, with the same volume. After general anesthesia, were submitted to two paracentesis of the both eyes to collect 0.2mL of first and second aqueous. The samples were submitted to Bradford test, wich proteins concentrations were  15.98mg/dL ± 4.48 e 11.46mg/dL ± 2.72 for the right and the left eyes, respectively, on the first paracentesis and 119.8mg/dL ± 6.74 e 120.63mg/dL ± 22.4 for the right and the left eyes, on the second paracentesis. There was no significant statistically differences between the protein values of the treated eyes in comparison with the control one. When compared, the proteins concentrations between the first and second paracentesis of the right and left eyes, statistic differences were found between these two moments (p<0.001. SDS-PAGE showed differences in the protein patterns of aqueous humor in result of the paracentesis.

    KEY WORDS: Aqueous humor, eye, flunixin meglumine, paracentesis, proteíns.

    Avaliaram-se os efeitos da flunixina meglumina, pela via subconjuntival, sobre as proteínas do humor aquoso de olhos de cães submetidos à paracentese da câmara anterior. Dez animais adultos, clinicamente sadios, receberam, por aplicação subconjuntival, flunixina meglumina (1,1mg/kg no olho direito e solução salina estéril a 0,9% no olho esquerdo, em igual volume. Mediante anestesia geral, foram submetidos a duas paracenteses de ambos os olhos para coleta de 0,2mL de aquoso primário e secundário, respectivamente. As amostras foram submetidas ao Teste de Bradford, cujas concentrações proteicas (média e desvio-padrão obtidas foram de 15

  15. Serous retinal detachment after trabeculectomy in angle recession glaucoma

    Directory of Open Access Journals (Sweden)

    Roy, Avik Kumar

    2015-12-01

    Full Text Available An 18-year-old male with 360 degree angle recession after blunt trauma in his right eye developed uncontrolled intraocular pressure (IOP despite four antiglaucoma medications (AGM with advancing disc damage. He underwent trabeculectomy with intraoperative mitomycin-c (MMC application. There was an intraoperative vitreous prolapse which was managed accordingly. On post-surgery day 1, he had shallow choroidal detachment superiorly with non-recordable IOP. This was deteriorated 1 week postoperatively as choroidal detachment proceeded to serous retinal detachment. He was started with systemic steroid in addition to topical route. The serous effusions subsided within 2 weeks time. At the last follow up at 3 months, he was enjoying good visual acuity, deep anterior chamber, diffuse bleb, an IOP in low teens off any AGM and attached retina. This case highlights the rare occurrence of serous retinal detachment after surgical management of angle recession glaucoma.

  16. Anterior segment parameters: comparison of 1-piece and 3-piece acrylic foldable intraocular lenses.

    Science.gov (United States)

    Behrouz, Mahmoud Jabbarvand; Kheirkhah, Ahmad; Hashemian, Hesam; Nazari, Rahman

    2010-10-01

    To compare anterior segment parameters between 1-piece and 3-piece acrylic foldable intraocular lenses (IOLs). Farabi Eye Hospital, Tehran, Iran. Prospective randomized comparative case series. Eyes scheduled for phacoemulsification were randomized into 2 equal groups to receive a 1-piece (AcrySof SA60AT) or 3-piece (AcrySof MA60AC) foldable acrylic IOL. Scheimpflug imaging (Pentacam) was used to measure anterior segment parameters, including anterior chamber depth (ACD), anterior chamber angle (ACA), and anterior chamber volume (ACV), preoperatively and 1 week and 3 months postoperatively. The study evaluated 125 eyes (123 patients). There was a statistically significant postoperative increase in ACD, ACA, and ACV at 1 week and 3 months in both IOL groups. Although the mean ACD was significantly higher in the 3-piece group at 1 week, there was no significant between-group difference in ACD, ACA, or ACV at 3 months. There was no significant change in anterior segment parameters from 1 week to 3 months in the 1-piece group; however, the 3-piece group had statistically significant decreases in ACD, ACA, and ACV. Refraction remained stable throughout the follow-up in the 1-piece group but showed a significant myopic shift from 1 week to 3 months in the 3-piece group. After phacoemulsification, the 1-piece acrylic foldable IOL showed little axial movement and provided stable refraction throughout the follow-up. The 3-piece IOL had significant forward movement and led to a myopic shift within 3 months postoperatively. Results indicate that spectacles can be prescribed earlier in eyes with a 1-piece IOL. Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  17. Phacoemulsification treatment of subjects with acute primary angle closure and chronic primary angle-closure glaucoma.

    Science.gov (United States)

    Zhuo, Ye-Hong; Wang, Mei; Li, Ying; Hao, Yuan-Tao; Lin, Min-Kai; Fang, Min; Ge, Jian

    2009-12-01

    To investigate and compare the effects of phacoemulsification as an initial procedure to control intraocular pressure (IOP) in eyes with acute primary angle closure (APAC) and chronic primary angle-closure glaucoma (CPACG) with coexisting cataracts and peripheral anterior synechiae (PAS) of greater than 180 degrees. Prospective, cross-sectional study. Thirteen patients (13 eyes) with APAC and 10 patients (10 eyes) with CPACG were enrolled in the study. IOP control in the 2 groups was compared at final follow-up. Other outcome measures included visual acuity, anterior chamber depth, gonioscopic appearance, and complications. The postoperative IOP was reduced in both the APAC and CPACG groups. As assessed at last follow-up (median 6 mo), IOP in the APAC group was significantly lower than that in the CPACG group. The absolute success rate was 100% in the APAC group and 80% in the CPACG group. The number of hypotensive medications decreased in both APAC and CPACG group. The postoperative degree of PAS was relieved in 11 of 12 eyes with APAC and 5 of 9 eyes with CPACG. Initial phacoemulsification performed to provide short-term control of IOP is more efficacious in patients with APAC than in those with CPACG, especially when PAS is greater than 180 degrees.

  18. Chamber transport

    International Nuclear Information System (INIS)

    Olson, Craig L.

    2001-01-01

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system

  19. The HBN Angle

    Directory of Open Access Journals (Sweden)

    Harsh Bhagvatiprasad Dave

    2015-01-01

    Full Text Available Aim: The purpose of this study was to establish a new cephalometric measurement, named the Harsh Bhagvatiprasad Nita angle (HBN, to assess the sagittal jaw relationship with accuracy and reproducibility. Materials and Methods: Three hundred pretreatment lateral cephalograms (100 each of Class I, II, and III were taken from the Department of Orthodontics and Dentofacial Orthopedics of Rajasthan Dental College and Hospital, Jaipur (Rajasthan and were subdivided into skeletal Class I, II, and III based on ANB, Wits appraisal, and Beta angle. This angle uses 3 skeletal landmarks the "C" (apparent axis of the condyle, "M" (midpoint of the premaxilla, and "G" (center of the largest circle that is tangent to the internal inferior, anterior, and posterior surfaces of the mandibular symphysis. Results: The result of the mean and standard deviation for the HBN angle were calculated in all three skeletal groups. After using one-way analysis of variance and post-hoc multiple comparisons by using Tukey′s honestly significant difference, homogeneous subsets, receiver operating characteristics (ROC curve - to differentiate Class II with Class I, ROC curve - to differentiate Class III with Class I, Reliability analysis with interclass correlation of HBN angle with other angles, we obtained results that showed that a patient with a HBN angle 40° and 46° can be considered to have a Class I skeletal pattern. Conclusions: A new angle, the HBN angle, was developed as a diagnostic aid to evaluate the sagittal jaw relationship more consistently. HBN angle 40° and 46° can be considered to have a Class I skeletal pattern, a more acute HBN angle indicates a Class II skeletal pattern, and a more obtuse HBN angle indicates a Class III skeletal pattern.

  20. Bilateral Acute Angle-Closure Glaucoma Induced By Escitalopram

    Directory of Open Access Journals (Sweden)

    Dilbade Yıldız Ekinci

    2014-10-01

    Full Text Available Escitalopram is an antidepressant of the selective serotonin reuptake inhibitor(SSRI class. In this manuscript, we report the case of a female patient who developed bilateral acute angle-closure glaucoma induced by escitalopram. A 46-year-old female patient was admitted to our ophthalmology clinic with complaints of severe pain around the both eyes, headache, nausea, and vomiting for two days. In her past medical history, she was using escitalopram for depression for two years. Visual acuity was at hand movement level in both eyes. Anterior segment examination showed bilateral diffuse conjunctival hyperemia, corneal edema, shallow anterior chamber, and fixed dilated pupils. Intraocular pressure was 47 mmHg in the right and 68 mmHg in the left eye. The diagnosis was acute angle-closure glaucoma, and the escitalopram medication was discontinued. She was treated with topical and systemic antiglaucomatous medication. After the cornea become clear, bilateral peripheral laser iridotomy was done. In the following year, she did not begin escitalopram medication again and no other acute angle-closure attack was seen. (Turk J Ophthalmol 2014; 44:396-9

  1. Anterior segment sparing to reduce charged particle radiotherapy complications in uveal melanoma

    International Nuclear Information System (INIS)

    Daftari, Inder K.; Char, Devron H.; Verhey, Lynn J.; Castro, Joseph R.; Petti, Paula L.; Meecham, William J.; Kroll, Stewart; Blakely, Eleanor A.

    1997-01-01

    Purpose: The purpose of this investigation is to delineate the risk factors in the development of neovascular glaucoma (NVG) after helium-ion irradiation of uveal melanoma patients and to propose treatment technique that may reduce this risk. Methods and Materials: 347 uveal melanoma patients were treated with helium-ions using a single-port treatment technique. Using univariate and multivariate statistics, the NVG complication rate was analyzed according to the percent of anterior chamber in the radiation field, tumor size, tumor location, sex, age, dose, and other risk factors. Several University of California San Francisco-Lawrence Berkeley National Laboratory (LBNL) patients in each size category (medium, large, and extralarge) were retrospectively replanned using two ports instead of a single port. By using appropriate polar and azimuthal gaze angles or by treating patients with two ports, the maximum dose to the anterior segment of the eye can often be reduced. Although a larger volume of anterior chamber may receive a lower dose by using two ports than a single port treatment. We hypothesize that this could reduce the level of complications that result from the irradiation of the anterior chamber of the eye. Dose-volume histograms were calculated for the lens, and compared for the single and two-port techniques. Results: NVG developed in 121 (35%) patients. The risk of NVG peaked between 1 and 2.5 years posttreatment. By univariate and multivariate analysis, the percent of lens in the field was strongly correlated with the development of NVG. Other contributing factors were tumor height, history of diabetes, and vitreous hemorrhage. Dose-volume histogram analysis of single-port vs. two-port techniques demonstrate that for some patients in the medium and large category tumor groups, a significant decrease in dose to the structures in the anterior segment of the eye could have been achieved with the use of two ports. Conclusion: The development of NVG after

  2. New comparative ultrasound biomicroscopic findings between fellow eyes of acute angle closure and glaucomatous eyes with narrow angle.

    Science.gov (United States)

    Mérula, Rafael Vidal; Cronemberger, Sebastião; Diniz Filho, Alberto; Calixto, Nassim

    2008-01-01

    To compare morphometric features between fellow acute primary angle-closure (APAC) eyes and glaucomatous or suspect eyes with narrow angle (NA). Fellow eyes of 30 patients with unilateral APAC and 30 with NA were evaluated by ultrasound biomicroscopy (UBM) under light and dark conditions. UBM parameters such as anterior chamber depth (ACD), angle opening distance at 250 microm/500 microm from the scleral spur (AOD250/AOD500), trabecular ciliary process distance (TCPD) and iris-lens contact distance (ILCD) were measured in the superior (SQ) and inferior (IQ) quadrants. Significant differences between APAC fellow and NA eyes were found in ACD, P<0.001; AOD250 at SQ and IQ, P<0.001; AOD500 at SQ and IQ, P<0.001; TCPD light, P=0.010 and TCPD dark at SQ, P=0.031; and TCPD light at IQ, P=0.010. Significant differences between light and dark examinations of APAC fellow eyes were found in ILCD (P=0.009) at SQ and ILCD at IQ (P=0.006), and of NA eyes in ILCD at SQ (P=0.047) and ILCD at IQ (P<0.001). APAC fellow eyes have a more crowded anterior segment and shallower ACD than NA eyes. ILCD decreases in both groups when the illumination conditions change from light to dark.

  3. The analysis of clinical effect of phacoemulsification on primary angle-closure glaucoma with cataract

    Directory of Open Access Journals (Sweden)

    Ling Zhao

    2013-07-01

    Full Text Available AIM:To evaluate the clinical outcomes and affected factors of prognosis of cataract extraction by phacoemulsification with intraocular lens implantation in eyes with primary angle-closure glaucoma(PACGand co-existing cataract.METHODS: Totally 60 cases(70 eyesof PACG with cataract, including 43 eyes with acute primary angle-closure glaucoma(APACG, 27 eyes of chronic primary angle-closure glaucoma(CPACG. The main outcome measures included: visual acuity, intraocular pressure, gonioscopy, depth of anterior chamber(ACD. Patients were examined 6 months after surgery.RESULTS: After phacoemulsification, visual acuity was improved(PPPPCONCLUSION:Phacoemulsification is more effective for acute APACG than for CPACG.

  4. A novel method for measuring anterior segment area of the eye on ultrasound biomicroscopic images using photoshop.

    Directory of Open Access Journals (Sweden)

    Zhonghao Wang

    Full Text Available To describe a novel method for quantitative measurement of area parameters in ocular anterior segment ultrasound biomicroscopy (UBM images using Photoshop software and to assess its intraobserver and interobserver reproducibility.Twenty healthy volunteers with wide angles and twenty patients with narrow or closed angles were consecutively recruited. UBM images were obtained and analyzed using Photoshop software by two physicians with different-level training on two occasions. Borders of anterior segment structures including cornea, iris, lens, and zonules in the UBM image were semi-automatically defined by the Magnetic Lasso Tool in the Photoshop software according to the pixel contrast and modified by the observers. Anterior chamber area (ACA, posterior chamber area (PCA, iris cross-section area (ICA and angle recess area (ARA were drawn and measured. The intraobserver and interobserver reproducibilities of the anterior segment area parameters and scleral spur location were assessed by limits of agreement, coefficient of variation (CV, and intraclass correlation coefficient (ICC.All of the parameters were successfully measured by Photoshop. The intraobserver and interobserver reproducibilities of ACA, PCA, and ICA were good, with no more than 5% CV and more than 0.95 ICC, while the CVs of ARA were within 20%. The intraobserver and interobserver reproducibilities for defining the spur location were more than 0.97 ICCs. Although the operating times for both observers were less than 3 minutes per image, there was significant difference in the measuring time between two observers with different levels of training (p<0.001.Measurements of ocular anterior segment areas on UBM images by Photoshop showed good intraobserver and interobserver reproducibilties. The methodology was easy to adopt and effective in measuring.

  5. Doriot Climatic Chambers

    Data.gov (United States)

    Federal Laboratory Consortium — The Doriot Climatic Chambers are two, 60-feet long, 11-feet high, 15-feet wide chambers that are owned and operated by NSRDEC. The Doriot Climatic Chambers are among...

  6. Multiple chamber ionization detector

    International Nuclear Information System (INIS)

    Solomon, E.E.

    1980-01-01

    A multi-chambered ionisation detector enables the amount of radiation entering each chamber from a single radioactive, eg β, source to be varied by altering the proportion of the source protruding into each chamber. Electrodes define chambers and an extended radioactive source is movable to alter the source length in each chamber. Alternatively, the source is fixed relative to outer electrodes but the central electrode may be adjusted by an attached support altering the chamber dimensions and hence the length of source in each. Also disclosed are a centrally mounted source tiltable towards one or other chamber and a central electrode tiltable to alter chamber dimensions. (U.K.)

  7. Directed Energy Anechoic Chamber

    Data.gov (United States)

    Federal Laboratory Consortium — The Directed Energy Anechoic Chamber comprises a power anechoic chamber and one transverse electromagnetic cell for characterizing radiofrequency (RF) responses of...

  8. Clinical outcomes of pars plicata anterior vitrectomy: 2-year results

    Directory of Open Access Journals (Sweden)

    Priya Narang

    2015-01-01

    Full Text Available Purpose: To demonstrate the safety and outcome of a surgical approach that uses pars plicata site for anterior vitrectomy during phacoemulsification procedure complicated by posterior capsule rupture and residual cortical matter. Design: Single center, retrospective, interventional, noncomparative study. Materials and Methods: Medical records of a consecutive series of 35 eyes of 35 patients who underwent pars plicata anterior vitrectomy (PPAV were reviewed. The main outcome measures were corrected and uncorrected distance visual acuity (CDVA, UDVA, early and late postoperative complications and intraocular pressure (IOP. Ultrasound biomicroscopic (UBM evaluation of sclerotomy site and spectral domain optical coherence tomography analysis for central macular thickness (CMT was performed. The final visual outcome at 2 years was evaluated. Results: At 2 years follow-up, the mean postoperative UDVA (logarithm of the minimum angle of resolution [logMAR] and CDVA (logMAR was 0.49 ± 0.26 and 0.19 ± 0.14, respectively. There was no significant change in the IOP (P = 0.061 and the mean CMT at 2 years was 192.5 ± 5.54 mm. The postoperative UBM image of the sclerotomy site at 8 weeks demonstrated a clear wound without any vitreous adhesion or incarceration. Intraoperative hyphema was seen in 1 (2.8% case and postoperative uveitis was seen in 2 (5.7% cases, which resolved with medications. No case of an iatrogenic retinal break or retinal detachment was reported. Conclusions: PPAV enables a closed chamber approach, allows thorough cleanup of vitreous in the pupillary plane and anterior chamber and affords better access to the subincisional and retropupillary cortical remnant with a significant visual outcome and an acceptable complication rate.

  9. Geometric approach to the design of an imaging probe to evaluate the iridocorneal angle structures

    Science.gov (United States)

    Hong, Xun Jie Jeesmond; V. K., Shinoj; Murukeshan, V. M.; Baskaran, M.; Aung, Tin

    2017-06-01

    Photographic imaging methods allow the tracking of anatomical changes in the iridocorneal angle structures and the monitoring of treatment responses overtime. In this work, we aim to design an imaging probe to evaluate the iridocorneal angle structures using geometrical optics. We first perform an analytical analysis on light propagation from the anterior chamber of the eye to the exterior medium using Snell's law. This is followed by adopting a strategy to achieve uniform near field irradiance, by simplifying the complex non-rotational symmetric irradiance distribution of LEDs tilted at an angle. The optimization is based on the geometric design considerations of an angled circular ring array of 4 LEDs (or a 2 × 2 square LED array). The design equation give insights on variable parameters such as the illumination angle of the LEDs, ring array radius, viewing angle of the LEDs, and the working distance. A micro color CCD video camera that has sufficient resolution to resolve the iridocorneal angle structures at the required working distance is then chosen. The proposed design aspects fulfil the safety requirements recommended by the International Commission on Non-ionizing Radiation Protection.

  10. Clinical observation of 3 minutes dark-room provocative test in patients with laser peripheral iridectomy in the fellow eyes of acute angle-closure glaucoma

    Directory of Open Access Journals (Sweden)

    Tao Liang

    2017-07-01

    Full Text Available AIM:To observe related biological parameters of 3 minutes dark-room provocative test in patients with laser peripheral iridectomy(LPIin the fellow eyes of acute primary angle-closure(APACby ultrasound biomicroscopy(UBM. To explore the risk factors in primary angle closure suspect(PACSpatients with progressive angle closure after LPI. METHODS: Seventy-eight eyes of APAC patients without peripheral anterior synechia were selected. Each eye underwent 3 minutes dark-room provocative test after LPI. Anterior segment parameters, including anterior chamber depth(ACD, anterior chamber angle open distance500(AOD500, peripheral iris thickness(PIT, iris convex(IC, the position of iris insertion and trabecular-ciliary process distance(TCPD, and the number of positional angle closure(NPACwere observed and analyzed by statistic methods. RESULTS:Patients with APAC were examined by UBM after LPI and 26 eyes(33%occurs at least one positional angle closure,19 eyes(24%were positive in 3 minutes dark-room provocative test among them. It occurs a positive relationship between the elevation intraocular pressure and the number of positional angle closure in dark-room provocative test(r=0.84, P500, IT and IC were significantly changed from normal light to darkroom between positional angle closure positive group and positional angle closure negative group(all P500(P=0.003, IT(P=0.012, IC(P=0.043, TPCD(P=0.015, the position of iris insertion(P=0.024were correlative factors of positive results. In multiple-factor analysis, only IT(P=0.011, TPCD(P=0.009, iris root attachment points(P=0.02were independent risk factors of positive results. CONCLUSION:A certain proportion of patients with PACS after LPI appeared positional angle closure in a dark room. Peripheral iris hypertrophy, anterior displacement of the ciliary body and iris root attachment points are vital risk factors. Long-term follow-up study and intervention treatment are required in these patients after LPI.

  11. New comparative clinical and biometric findings between acute primary angle-closure and glaucomatous eyes with narrow angle

    Directory of Open Access Journals (Sweden)

    Rafael Vidal Mérula

    2010-12-01

    Full Text Available Purpose: To compare, clinically and biometrically, affected and fellow acute primary angle-closure (APAC eyes and glaucomatous eyes with narrow angle (NA. Methods: Comparative case series; 30 patients with APAC and 27 glaucomatous patients with NA were evaluated. Keratometry (K, central corneal thickness (CCT, lens thickness (LT, axial length (AL and anterior chamber depth (ACD were measured. Parameters defined as lens posisiton (LP and relative lens position (RLP were calculated. Results: Biometric difference between APAC-affected and fellow eyes was found only in LP (P=0.046. When fellow eyes were compared to glaucomatous eyes with NA, differences were found in ACD (P=0.009, AL (P=0.010, and LT/AL (P=0.005. The comparison between APAC-affected and glaucomatous eyes with NA showed significant differences in almost all biometric parameters, except for LT (P=0.148 and RLP (P=0.374. We found that the logistic regression model (LRM, built with three parameters (K, CCT and LT/AL, higher than 0.334 could be a reasonable instrument to differentiate APAC eyes from glaucomatous eyes with NA. Conclusions: This study showed that APAC-affected and fellow eyes have similar biometric features, and glaucomatous eyes with NA have a less crowded anterior segment. The LRM built showed promising results in distinguishing APAC from glaucomatous eyes with NA.

  12. New comparative clinical and biometric findings between acute primary angle-closure and glaucomatous eyes with narrow angle.

    Science.gov (United States)

    Mérula, Rafael Vidal; Cronemberger, Sebastião; Diniz Filho, Alberto; Calixto, Nassim

    2010-01-01

    To compare, clinically and biometrically, affected and fellow acute primary angle-closure (APAC) eyes and glaucomatous eyes with narrow angle (NA). Comparative case series; 30 patients with APAC and 27 glaucomatous patients with NA were evaluated. Keratometry (K), central corneal thickness (CCT), lens thickness (LT), axial length (AL) and anterior chamber depth (ACD) were measured. Parameters defined as lens posisiton (LP) and relative lens position (RLP) were calculated. Biometric difference between APAC-affected and fellow eyes was found only in LP (P=0.046). When fellow eyes were compared to glaucomatous eyes with NA, differences were found in ACD (P=0.009), AL (P=0.010), and LT/AL (P=0.005). The comparison between APAC-affected and glaucomatous eyes with NA showed significant differences in almost all biometric parameters, except for LT (P=0.148) and RLP (P=0.374). We found that the logistic regression model (LRM), built with three parameters (K, CCT and LT/AL), higher than 0.334 could be a reasonable instrument to differentiate APAC eyes from glaucomatous eyes with NA. This study showed that APAC-affected and fellow eyes have similar biometric features, and glaucomatous eyes with NA have a less crowded anterior segment. The LRM built showed promising results in distinguishing APAC from glaucomatous eyes with NA.

  13. Changes in Anterior Segment Morphology of Iris Bombe before and after Laser Peripheral Iridotomy in Patients with Uveitic Secondary Glaucoma

    Directory of Open Access Journals (Sweden)

    Wakako Ikegawa

    2016-01-01

    Full Text Available Purpose. To quantify changes in anterior segment (AS parameters after laser peripheral iridotomy (LPI using AS-optical coherence tomography (OCT of iris bombe. Method. AS images of eight eyes were captured before and after iris bombe and more than 2 weeks after LPI (post-LPI using AS-OCT. We compared the following AS parameters: anterior chamber depth (ACD, anterior chamber volume (ACV, iris curvature (IC, iris thickness at 500 μm from the scleral spur (IT-1 in the middle between the iris root and pupillary margin (IT-2 and 500 μm from the pupillary margin (IT-3 to the anterior chamber angle (ACA (angle opening distance [AOD750], and trabecular iris space area. Results. Mean IT-1 and IT-3, but not IT-2, were lower after iris bombe (IT-1, P=0.001; IT-2, P=0.081; and IT-3, P=0.001. There were no significant differences between ACD at pre-LPI and before iris bombe (P=0.096. The mean ACV and AOD750 of iris bombe increased at post-LPI (ACV, P<0.01, and AOD750, P<0.05. The mean IT-1, IT-2, and IT-3 increased at post-LPI (all, P≤0.01. IC decreased at post-LPI (P<0.001, and ACD at post-LPI did not change. Conclusions. The iris extends and becomes thinner during iris bombe. LPI during bombe decreases the IC and increases the ACV and ACA.

  14. 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.

  15. Compact ion chamber based neutron detector

    Science.gov (United States)

    Derzon, Mark S.; Galambos, Paul C.; Renzi, Ronald F.

    2015-10-27

    A directional neutron detector has an ion chamber formed in a dielectric material; a signal electrode and a ground electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; readout circuitry which is electrically coupled to the signal and ground electrodes; and a signal processor electrically coupled to the readout circuitry. The ion chamber has a pair of substantially planar electrode surfaces. The chamber pressure of the neutron absorbing material is selected such that the reaction particle ion trail length for neutrons absorbed by the neutron absorbing material is equal to or less than the distance between the electrode surfaces. The signal processor is adapted to determine a path angle for each absorbed neutron based on the rise time of the corresponding pulse in a time-varying detector signal.

  16. Association Between Baseline Iris Thickness and Prophylactic Laser Peripheral Iridotomy Outcomes in Primary Angle Closure Suspects

    Science.gov (United States)

    Lee, Roland Y.; Kasuga, Toshimitsu; Cui, Qi N.; Porco, Travis C.; Huang, Guofu; He, Mingguang; Lin, Shan C.

    2014-01-01

    Objective To evaluate the association between baseline measurements of iris thickness at three positions and change in anterior segment biometric parameters after prophylactic laser peripheral iridotomy (LPI). Design Prospective clinical cohort study. Participants Fifty-two eyes of 52 nonglaucomatous subjects with anatomically narrow angles. Methods Anterior segment optical coherence tomography images captured before and after LPI were analyzed using customized software, the Zhongshan Angle Assessment Program. Differences in preoperative and postoperative measurements for anterior segment biometric parameters were compared by paired Student’s t-tests. Multivariate linear regression models, adjusted for age, sex, ethnicity, and preoperative pupil diameter, were used to examine the association between the baseline measurements of iris thickness at three positions and the change in anterior segment biometric parameters after LPI. Main Outcome Measures Baseline iris thickness measured at 750μm (IT750) and 2000μm (IT2000) from the scleral spur and maximal iris thickness (ITM). Changes in iris curvature (ICURV) and trabecular–iris space area at 500μm (TISA500) and 750μm (TISA750) from the scleral spur after LPI. Results ICURV significantly decreased, while TISA500 and TISA750 significantly increased following LPI (all Piris thickness are associated with greater decrease in ICURV and increases in TISA500 and TISA750 after LPI. This suggests that eyes with thinner irides undergoing LPI were more likely to exhibit greater magnitude of change in terms of flattening of the iris convexity (i.e., ICURV) and widening of the anterior chamber angle (i.e., TISA500 and TISA750). PMID:24534754

  17. Laser Peripheral Iridotomy in Primary Angle Closure: A Report by the American Academy of Ophthalmology.

    Science.gov (United States)

    Radhakrishnan, Sunita; Chen, Philip P; Junk, Anna K; Nouri-Mahdavi, Kouros; Chen, Teresa C

    2018-02-23

    To examine the efficacy and complications of laser peripheral iridotomy (LPI) in subjects with primary angle closure (PAC). Literature searches in the PubMed and Cochrane databases were last conducted in August 2017 and yielded 300 unique citations. Of these, 36 met the inclusion criteria and were rated according to the strength of evidence; 6 articles were rated level I, 11 articles were rated level II, and 19 articles were rated level III. Reported outcomes were change in angle width, effect on intraocular pressure (IOP) control, disease progression, and complications. Most of the studies (29/36, 81%) included only Asian subjects. Angle width (measured by gonioscopy, ultrasound biomicroscopy, and anterior segment OCT) increased after LPI in all stages of angle closure. Gonioscopically defined persistent angle closure after LPI was reported in 2% to 57% of eyes across the disease spectrum. Baseline factors associated with persistent angle closure included narrower angle and parameters representing nonpupillary block mechanisms of angle closure, such as a thick iris, an anteriorly positioned ciliary body, or a greater lens vault. After LPI, further treatment to control IOP was reported in 0%-8% of PAC suspect (PACS), 42% to 67% of PAC, 21% to 47% of acute PAC (APAC), and 83%-100% of PAC glaucoma (PACG) eyes. Progression to PACG ranged from 0% to 0.3% per year in PACS and 0% to 4% per year in PAC. Complications after LPI included IOP spike (8-17 mmHg increase from baseline in 6%-10%), dysphotopsia (2%-11%), anterior chamber bleeding (30%-41%), and cataract progression (23%-39%). Laser peripheral iridotomy increases angle width in all stages of primary angle closure and has a good safety profile. Most PACS eyes do not receive further intervention, whereas many PAC and APAC eyes, and most PACG eyes, receive further treatment. Progression to PACG is uncommon in PACS and PAC. There are limited data on the comparative efficacy of LPI versus other treatments for the

  18. Effects of Laser Peripheral Iridotomy in Subgroups of Primary Angle Closure Based on Iris Insertion

    Directory of Open Access Journals (Sweden)

    Sung-Cheol Yun

    2015-01-01

    Full Text Available Purpose. To investigate the effect of laser peripheral iridotomy (LPI in subgroups of primary angle closure based on iris insertion configuration. Methods. Anterior segment optical coherence tomography (AS-OCT images were obtained before and two weeks after LPI. Qualitative classification of angle closure eyes according to iris insertion (basal insertion group (BG and nonbasal insertion group (NBG was performed. Anterior chamber depth (ACD, lens vault (LV, iris curvature, iris area, iris thickness (IT750, and angle opening distance (AOD750 750 microns from scleral spur were calculated. Uni- and multivariate regression analysis was carried out to evaluate factors associated with AOD750 before and after LPI. Results. Ninety-two eyes of 92 subjects were categorized as NBG (39 eyes or BG (53 eyes. The mean change after LPI was not significantly different between two groups in all parameters. In both groups, AOD750 was affected by ACD (p<0.001, p=0.044 before LPI. AOD750 was affected by LV (p=0.012 in NBG, but by ACD (p<0.001 and IT750 (p=0.039 in BG after LPI. Conclusions. The outcomes of LPI are not significantly different between angle closure subgroups with different iris insertions. However, factors affecting AOD750 show differences between two subgroups after LPI.

  19. Scoliosis angle

    International Nuclear Information System (INIS)

    Marklund, T.

    1978-01-01

    The most commonly used methods of assessing the scoliotic deviation measure angles that are not clearly defined in relation to the anatomy of the patient. In order to give an anatomic basis for such measurements it is proposed to define the scoliotic deviation as the deviation the vertebral column makes with the sagittal plane. Both the Cobb and the Ferguson angles may be based on this definition. The present methods of measurement are then attempts to measure these angles. If the plane of these angles is parallel to the film, the measurement will be correct. Errors in the measurements may be incurred by the projection. A hypothetical projection, called a 'rectified orthogonal projection', is presented, which correctly represents all scoliotic angles in accordance with these principles. It can be constructed in practice with the aid of a computer and by performing measurements on two projections of the vertebral column; a scoliotic curve can be represented independent of the kyphosis and lordosis. (Auth.)

  20. Glove box chamber

    International Nuclear Information System (INIS)

    Cox, M.E.; Cox, M.E.

    1975-01-01

    An environmental chamber is described which enables an operator's hands to have direct access within the chamber without compromising a special atmosphere within such chamber. A pair of sleeves of a flexible material are sealed to the chamber around associated access apertures and project outwardly from such chamber. Each aperture is closed by a door which is openable from within the sleeve associated therewith so that upon an operator inserting his hand and arm through the sleeve, the operator can open the door to have access to the interior of the chamber. A container which is selectively separable from the remainder of the chamber is also provided to allow objects to be transferred from the chamber without such objects having to pass through the ambient atmosphere. An antechamber permitting objects to be passed directly into the chamber from the ambient atmosphere is included. (auth)

  1. A novel method for measuring anterior segment area of the eye on ultrasound biomicroscopic images using photoshop.

    Science.gov (United States)

    Wang, Zhonghao; Liang, Xuanwei; Wu, Ziqiang; Lin, Jialiu; Huang, Jingjing

    2015-01-01

    To describe a novel method for quantitative measurement of area parameters in ocular anterior segment ultrasound biomicroscopy (UBM) images using Photoshop software and to assess its intraobserver and interobserver reproducibility. Twenty healthy volunteers with wide angles and twenty patients with narrow or closed angles were consecutively recruited. UBM images were obtained and analyzed using Photoshop software by two physicians with different-level training on two occasions. Borders of anterior segment structures including cornea, iris, lens, and zonules in the UBM image were semi-automatically defined by the Magnetic Lasso Tool in the Photoshop software according to the pixel contrast and modified by the observers. Anterior chamber area (ACA), posterior chamber area (PCA), iris cross-section area (ICA) and angle recess area (ARA) were drawn and measured. The intraobserver and interobserver reproducibilities of the anterior segment area parameters and scleral spur location were assessed by limits of agreement, coefficient of variation (CV), and intraclass correlation coefficient (ICC). All of the parameters were successfully measured by Photoshop. The intraobserver and interobserver reproducibilities of ACA, PCA, and ICA were good, with no more than 5% CV and more than 0.95 ICC, while the CVs of ARA were within 20%. The intraobserver and interobserver reproducibilities for defining the spur location were more than 0.97 ICCs. Although the operating times for both observers were less than 3 minutes per image, there was significant difference in the measuring time between two observers with different levels of training (pPhotoshop showed good intraobserver and interobserver reproducibilties. The methodology was easy to adopt and effective in measuring.

  2. Uveal effusion following acute primary angle-closure: a retrospective case series

    Directory of Open Access Journals (Sweden)

    Jian-Gang Yang

    2017-03-01

    Full Text Available AIM: To evaluate the morphological changes in anterior segment in Chinese patients with uveal effusion (UE after the attack of acute primary angle-closure (APAC using ultrasound biomicroscopy (UBM, and to assess the clinical course and prognosis of the disease. METHODS: In a retrospective case series, 26 eyes in 26 consecutive patients diagnosed with UE after the treatment of intraocular pressure (IOP-lowering medication for the attack of APAC were enrolled. The unaffected fellow eyes served as controls. The morphological changes were observed by ultrasonography, slit lamp microscopy and gonioscopy. UBM was used to assess the degree and extent of effusion based on the analysis of parameters associated with UE. RESULTS: The mean IOP was 9.2 (SD 2.1 mm Hg at the diagnosis of UE after IOP-lowering medication, while 14.1 (SD, 2.6 mm Hg in the fellow eyes (P=0.000. The anterior chamber depth (ACD (P=0.000, angle opening distance at 500 μm (AOD500 (P<0.01 and anterior chamber angle (ACA (P<0.05 were decreased significantly, while ciliary body thickness (CBT (P<0.05 increased significantly in UE eyes. UE grade analysis showed 7 eyes in grade 1, 9 eyes in grade 2, and 10 eyes in grade 3. Quadrant scores were performed of 4 eyes in 1 quadrant, 3 eyes in 3 quadrants, and 19 eyes in 4 quadrants. There was the positive correlation between grade and quadrant score (r=0.644, P=0.000. The effusion on all eyes were recovered after medication, which mean IOP was 13.9 (SD, 2.8 mm Hg. CONCLUSION: UE is a frequent complication in Chinese patients after the attack of APAC, partially associated with hypotony. The severity of UE is correlation with height of effusion, extent of detachment, and shallower ACD.

  3. Chronic and Intermittent Angle Closure Caused by In-The-Bag Capsular Tension Ring and Intraocular Lens Dislocation in Patients With Pseudoexfoliation Syndrome.

    Science.gov (United States)

    Bochmann, Frank; Strümer, Jörg

    2017-11-01

    A subluxation or dislocation of the intraocular lens (IOL) is a well-known complication after cataract surgery in patients with pseudoexfoliation syndrome (PEX). Capsular tension rings (CTR) are frequently used to prevent postoperative complications caused by zonular weakness. Here we present a series of 7 cases, 2 with intermittent and 5 with acute angle closure caused by a combination of PEX-associated zonular weakness and a resulting unstable capsular bag-CTR-IOL complex. We describe the typical clinical course with elevated intraocular pressure, myopic shift, and shallowing of the anterior chamber in 7 patients with a new type of secondary angle closure. The diagnostic challenges and treatment options are discussed in detail. In all cases, the mechanism of angle closure identified by ultrasound biomicroscopy was an anterior dislocation of the peripheral iris by the capsular bag-CTR-IOL complex. The IOL was removed together with the capsular bag and the CTR and replaced by an iris-fixated IOL in all cases. We present a new type of secondary angle closure caused by an anterior dislocated capsular bag-CTR-IOL complex. The cause of both, this atypical presentation and the ineffectiveness of the laser peripheral iridotomy is the large diameter CTR. Therefore CTR implantation might also be the source of late postoperative complications. If a secondary angle closure associated with PEX and unstable capsular bag-CTR-IOL complex is encountered, IOL explantation and replacement by an iris-fixated IOL is a simple and effective treatment option.

  4. Plateau iris configuration in eyes with narrow-angle: an ultrasound biomicroscopic study.

    Science.gov (United States)

    Diniz Filho, Alberto; Cronemberger, Sebastião; Ferreira, Dollores Martins; Mérula, Rafael Vidal; Calixto, Nassim

    2010-01-01

    To investigate, through ultrasound biomicroscopy images, the presence of plateau iris configuration in eyes with narrow-angle from patients with open-angle glaucoma and in eyes with previous acute primary angle-closure and compare the biometric features of eyes with plateau iris configuration with those of normal eyes. Ultrasound biomicroscopic images from 196 patients with open-angle glaucoma and narrow-angle and 32 patients with acute primary angle-closure were retrospectively analyzed. The inclusion and specific criteria for the diagnosis of plateau iris configuration was the presence of an anterior positioning of the ciliary processes, supporting the peripheral iris so that it was parallel to the trabecular meshwork; the iris root had a steep rise from its insertion point, followed by a downward angulation from the corneoscleral wall; presence of a central flat iris plane; an absent (complete plateau iris configuration) or partially absent (incomplete plateau iris configuration) ciliary sulcus. The ultrasound biomicroscopic parameters were compared between complete and incomplete plateau iris configuration. The same parameters of both groups were compared with those of normal eyes. The following measurements were performed: anterior chamber depth; angle opening distance at 500 microm from the scleral spur; peripheral iris thickness at 500 microm from the scleral spur; iris-ciliary process distance; trabecular-ciliary process distance and angle recess area. Plateau iris configuration was found in 33 eyes of 20 (10.2%) out of 196 patients with open-angle glaucoma and narrow-angle and in 4 eyes of 2 (6.3%) out of 32 patients with acute primary angleclosure. Seventeen (77.3%) patients with plateau iris configuration were female and 5 (22.7%) male. Twenty-three (62.2%) out of 37 eyes had complete plateau iris configuration, and 14 (37.8%) had incomplete plateau iris configuration. Complete and incomplete plateau iris configuration presented similar biometric

  5. Efficacy of goniosynechialysis for advanced chronic angle-closure glaucoma

    Directory of Open Access Journals (Sweden)

    Qing G

    2012-10-01

    Full Text Available Guoping Qing,1,2 Ningli Wang,1 Dapeng Mu11Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Lab, Beijing, China; 2State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, ChinaPurpose: To evaluate the intraocular pressure (IOP-lowering efficacy of goniosynechialysis (GSL for advanced chronic angle-closure glaucoma (CACG using a simplified slit-lamp technique.Patients and methods: Patients with CACG with one severely affected eye with best-corrected visual acuity below 20/200 and a mildly or functionally unaffected fellow eye were enrolled in this study. All patients underwent ophthalmologic examinations including measurement of visual acuity, best-corrected visual acuity, and IOP; biomicroscopy; specular microscopy; fundus examination; and gonioscopy followed by anterior chamber paracentesis and GSL for nasal peripheral anterior synechiae in the eye with severe CACG.Results: Thirty patients (18 men, 12 women were identified as having CACG with an initial mean IOP of 47.1 ± 6.7 mmHg (range 39–61 mmHg in the severely affected eye. One week after GSL, the mean IOP of the treated eyes decreased to 19.3 ± 2.8 mmHg (range 14–26 mmHg without antiglaucoma medication (average decrease 27.7 ± 6.5 mmHg; range 16–41 mmHg, which was significant (P < 0.00001 compared with baseline. After an average follow-up period of 36.6 ± 1.0 months (range 35–38 months, the mean IOP stabilized at 17.4 ± 2.2 mmHg (range 12–21 mmHg. The nasal angle recess did not close again in any one of the patients during the follow-up period. The average significant (P < 0.00001 decrease in corneal endothelial cell density in the treated eyes was 260 ± 183 cells/mm2 (range 191–328 cells/mm2.Conclusions: Anterior chamber paracentesis and GSL lowers IOP in advanced CACG, though it may lead to mild corneal endothelial cell loss

  6. Qualitative evaluation of the iris and ciliary body by ultrasound biomicroscopy in subjects with angle closure.

    Science.gov (United States)

    Ku, Judy Y; Nongpiur, Monisha E; Park, Judy; Narayanaswamy, Arun K; Perera, Shamira A; Tun, Tin A; Kumar, Rajesh S; Baskaran, Mani; Aung, Tin

    2014-12-01

    To qualitatively analyze anterior chamber structures imaged by ultrasound biomicroscopy (UBM) in primary angle-closure patients. Subjects diagnosed as primary angle-closure suspect (PACS), primary angle-closure glaucoma (PACG), and previous acute primary angle closure (APAC) were recruited prospectively along with a group of normal controls. UBM was performed under standardized dark room conditions and qualitative assessment was carried out using a set of reference photographs of standard UBM images to categorize the various anatomic features related to angle configuration. These included overall and basal iris thicknesses, iris convexity, iris angulation, ciliary body size, and ciliary sulcus. A total of 60 PACS, 114 PACG, 41 APAC, and 33 normal controls were included. Patients were predominantly older Chinese females. After controlling the confounding effect of age and sex, eyes with overall thicker irides [medium odds ratio (OR) 3.58, thick OR 2.84] when compared with thin irides have a significantly higher likelihood of having PACS/PACG/APAC versus controls. Thicker basal iris component (medium OR 4.13, thick OR 3.39) also have higher likelihood of having angle closure when compared with thin basal iris thickness. Subjects with basal iris insertion, mild iris angulation, and large ciliary body have a higher OR of having angle closure. In contrast, the presence/absence of a ciliary sulcus did not influence the likelihood of angle closure. Eyes with thicker overall and basal iris thicknesses are more likely to have angle closure than controls. Other features that increase the likelihood of angle closure include basal iris insertion, mild iris angulation, and large ciliary body.

  7. bubble chamber lens

    CERN Multimedia

    Before the days of electronic detectors, visual techniques were used to detect particles, using detectors such as spark chambers and bubble chambers. This plexiglass lens was used to focus the image of tracks so they could be photographed.

  8. Neutron small angle scattering

    International Nuclear Information System (INIS)

    Ibel, K.

    1975-01-01

    The neutron small-angle scattering system at the High-Flux Reactor in Grenoble consists of three major parts: the supply of cold neutrons via bent neutron guides; the small angle camera D11; and the data handling facilities. The camera D11 has an overall length of 80 m. The effective length of the camera is variable. The length of the collimator before the fixed sample position can be reduced by movable neutron guides; the secondary flight path of 40 m full length contains detector sites in various positions. Thus, a large domain of momentum transfers can be exploited. Scattering angles between 5.10 -4 and 0.5 rad and neutron wavelengths from 0.2 to 2.0 nm are available with the same instrument and the same relative resolution. A large-area position-sensitive detector is used which allows simultaneous recording of intensities scattered into different angles; it is a multiwire proportional chamber. 3808 elements of 1 cm 2 are arranged in a two-dimensional matrix. Future development comprises an increase of the limit in the count rate due to the electronic interface between the detector and on-line computer, actually at 5.10 4 per sec. by one order of magnitude

  9. Dual ionization chamber

    International Nuclear Information System (INIS)

    Mallory, J.; Turlej, Z.

    1981-01-01

    Dual ionization chambers are provided for use with an electronic smoke detector. The chambers are separated by electrically-conductive partition. A single radiation source extends through the partition into both chambers, ionizing the air in each. The mid-point current of the device may be balanced by adjusting the position of the source

  10. First experiences with a slitlamp-adapted optical coherence tomography (OCT) system in the anterior and posterior segment of the eye

    Science.gov (United States)

    Hoerauf, Hans; Scholz, Christian; Engelhardt, Ralf; Koch, Peter; Laqua, Horst; Birngruber, Reginald

    1999-02-01

    Optical Coherence Tomography (OCT) is a new in vivo imaging device in ophthalmology. We investigated the diagnostic potentials of a slitlamp-adapted OCT in the examination of not only the posterior but also the anterior segment in vivo. Patients were examined with a new prototype of a slitlamp- adapted OCT (Fa.Schwind, D-Kleinostheim) in the anterior and posterior segment using 100 - 200 axial scans with 50 Hz scan frequency. The scan length is variable up to 7.5 mm. The software allows to evaluate the images in gray scale or false color. By the slitlamp-adapted OCT all anatomic structures and morphological changes anterior to the attenuating iris pigment epithelium including the anterior chamber angle can be demonstrated and measured precisely. Within the pupillary opening OCT-imaging of cataract, secondary cataract formation as well as the anterior vitreous can be performed. The slitlamp-adapted OCT also allows direct biomicroscopic control of the measured area in examinations of the posterior segment. The slitlamp-adapted OCT provides a new and helpful diagnostic tool, which allows a precise examination of the anterior and posterior segment of the eye. The advantage of this new method lies in the combination of the familiar examination technique and the simultaneous slitlamp view, which provides an exact position control. It is possible to do pachymetric studies of the cornea after photorefractive and phototherapeutic therapy. Of importance is the objective measurement of the chamber angle, which may improve pre- and postoperative evaluation and allow a better follow up documentation of glaucoma patients.

  11. Distinct iris gene expression profiles of primary angle closure glaucoma and primary open angle glaucoma and their interaction with ocular biometric parameters.

    Science.gov (United States)

    Seet, Li-Fong; Narayanaswamy, Arun; Finger, Sharon N; Htoon, Hla M; Nongpiur, Monisha E; Toh, Li Zhen; Ho, Henrietta; Perera, Shamira A; Wong, Tina T

    2016-11-01

    This study aimed to evaluate differences in iris gene expression profiles between primary angle closure glaucoma (PACG) and primary open angle glaucoma (POAG) and their interaction with biometric characteristics. Prospective study. Thirty-five subjects with PACG and thirty-three subjects with POAG who required trabeculectomy were enrolled at the Singapore National Eye Centre, Singapore. Iris specimens, obtained by iridectomy, were analysed by real-time polymerase chain reaction for expression of type I collagen, vascular endothelial growth factor (VEGF)-A, -B and -C, as well as VEGF receptors (VEGFRs) 1 and 2. Anterior segment optical coherence tomography (ASOCT) imaging for biometric parameters, including anterior chamber depth (ACD), anterior chamber volume (ACV) and lens vault (LV), was also performed pre-operatively. Relative mRNA levels between PACG and POAG irises, biometric measurements, discriminant analyses using genes and biometric parameters. COL1A1, VEGFB, VEGFC and VEGFR2 mRNA expression was higher in PACG compared to POAG irises. LV, ACD and ACV were significantly different between the two subgroups. Discriminant analyses based on gene expression, biometric parameters or a combination of both gene expression and biometrics (LV and ACV), correctly classified 94.1%, 85.3% and 94.1% of the original PACG and POAG cases, respectively. The discriminant function combining genes and biometrics demonstrated the highest accuracy in cross-validated classification of the two glaucoma subtypes. Distinct iris gene expression supports the pathophysiological differences that exist between PACG and POAG. Biometric parameters can combine with iris gene expression to more accurately define PACG from POAG. © 2016 The Authors. Clinical & Experimental Ophthalmology published by John Wiley & Sons Australia, Ltd on behalf of Royal Australian and New Zealand College of Ophthalmologists.

  12. Intraocular stability of an angle-supported phakic intraocular lens with changes in pupil diameter.

    Science.gov (United States)

    Alió, Jorge L; Piñero, David P; Sala, Esperanza; Amparo, Francisco

    2010-09-01

    To use anterior segment optical coherence tomography (AS-OCT) to evaluate the stability of a recently released angle-supported phakic intraocular lens (pIOL) in the anterior segment with changes in pupil diameter. Keratoconus Unit, Vissum Corporation, Alicante, Spain. In this observational cross-sectional study of consecutive eyes with moderate to high myopia, an AcrySof Cachet pIOL was implanted with the aim of minimizing the refractive error. An analysis of the position and stability of the pIOL before and after pharmacologic pupil dilation was performed 3 months postoperatively using the Visante AS-OCT system. A measurement protocol that included several anatomic parameters was developed and applied; the parameter values before and after dilation were compared. Twenty eyes of 20 patients ranging in age from 24 to 48 years old were evaluated. The anterior chamber depth increased significantly with pupil dilation (mean change 0.06 mm +/- 0.08 [SD]) (Por=.14). The angle-supported pIOL showed excellent intraocular behavior after pupil dilation, with no shortening of the distance between the pIOL and corneal endothelium at the center or peripheral edges of the pIOL. Copyright (c) 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  13. Differences between fellow eyes of acute and chronic primary angle closure (glaucoma): An ultrasound biomicroscopy quantitative study.

    Science.gov (United States)

    Li, Mengwei; Chen, Yuhong; Chen, Xiaoxiao; Zhu, Wenqing; Chen, Xueli; Wang, Xiaolei; Fang, Yuan; Kong, Xiangmei; Dai, Yi; Chen, Junyi; Sun, Xinghuai

    2018-01-01

    To compare various biometric parameters between fellow eyes of acute primary angle closure (glaucoma) [APAC(G)] and fellow eyes of chronic primary angle closure (glaucoma) [CPAC(G)]. Ultrasound biomicroscopy examinations were performed on 47 patients with unilateral APAC(G) and 41 patients with asymmetric CPAC(G) before laser peripheral iridotomy and pilocarpine treatment. Anterior chamber depth and width (ACD and ACW), lens vault (LV), iris curvature (IC), iris root distance (IRD), trabecular-ciliary process distance (TCPD), iris-ciliary process distance (ICPD), trabecular-ciliary angle (TCA), and other biometric parameters were compared between fellow eyes of APAC(G) and fellow eyes of CAPC(G). Compared with fellow eyes of CPAC(G), fellow eyes of APAC(G) had smaller ACD (P APAC(G) had smaller anterior segment dimensions, higher LV, more posterior iris insertion, greater IC, and more anteriorly rotated ciliary body compared with fellow eyes of CPAC(G). ACD, ICPD, and IRD were the three most important parameters that distinguish eyes predisposed to APAC(G) or CPAC(G).

  14. Correlation of the anterior ocular segment biometry with HbA1c level in type 2 diabetes mellitus patients.

    Directory of Open Access Journals (Sweden)

    Abd-Rashid Suraida

    Full Text Available To compare the anterior ocular segment biometry among Type 2 diabetes mellitus (DM with no diabetic retinopathy (DR and non-proliferative diabetic retinopathy (NPDR, and to evaluate the correlation of anterior ocular segment biometry with HbA1c level.A cross-sectional study was conducted in Hospital Universiti Sains Malaysia, Kelantan from November 2013 till May 2016 among Type 2 DM patients (DM with no DR and DM with NPDR. The patients were evaluated for anterior ocular segment biometry [central corneal thickness (CCT, anterior chamber width (ACW, angle opening distance (AOD and anterior chamber angle (ACA] by using Anterior Segment Optical Coherence Tomography (AS-OCT. Three ml venous blood was taken for the measurement of HbA1c.A total of 150 patients were included in this study (DM with no DR: 50 patients, DM with NPDR: 50 patients, non DM: 50 patients as a control group. The mean CCT and ACW showed significant difference among the three groups (p < 0.001 and p = 0.015 respectively. Based on post hoc result, there were significant mean difference of CCT between non DM and DM with NPDR (mean difference 36.14 μm, p < 0.001 and also between non DM and DM with no DR (mean difference 31.48 μm, p = 0.003. The ACW was significantly narrower in DM with NPDR (11.39 mm SD 0.62 compared to DM with no DR (11.76 mm SD 0.53 (p = 0.012. There were no significant correlation between HbA1c and all the anterior ocular segment biometry.Diabetic patients have significantly thicker CCT regardless of retinopathy status whereas ACW was significantly narrower in DM with NPDR group compared to DM with no DR. There was no significant correlations between HbA1c and all anterior ocular segment biometry in diabetic patients regardless of DR status.

  15. Comparison among different CT ionization chambers

    International Nuclear Information System (INIS)

    Castro, Maysa C. de; Xavier, Marcos; Caldas, Linda V.E.

    2015-01-01

    The dosimetry in computed tomography (CT) is carried out by the use of a pencil type ionization-chamber, because it has a uniform response at all angles relative to the incident beam of radiation, which is essential for CT equipment since the X-ray tube executes a circular movement around the table during irradiation. The commercial ionization chamber used to perform quality control procedures of this kind of equipment has a length of the sensitive volume of 10 cm. In the Calibration Laboratory of Instruments (LCI) of the IPEN there were already developed some prototypes with small differences in construction, when compared to commercially available ionization chambers. They have been used in previous studies and showed results within internationally acceptable limits. The ionization chambers tested in this study present the sensitive volume lengths of 1 cm, 3 cm and 10 cm. The objective of this study was to present results on the stability test of the three homemade ionization chambers and a commercial chamber, as well to obtain the calibration coefficients for each of them in CT standard X radiation beams. The obtained results for both characterization tests are within the recommended limits, except for the homemade ionization chambers with sensitive volume lengths of 3 cm and 1 cm in the case of the stability test. (author)

  16. Association between baseline iris thickness and prophylactic laser peripheral iridotomy outcomes in primary angle-closure suspects.

    Science.gov (United States)

    Lee, Roland Y; Kasuga, Toshimitsu; Cui, Qi N; Porco, Travis C; Huang, Guofu; He, Mingguang; Lin, Shan C

    2014-06-01

    To evaluate the association between baseline measurements of iris thickness at 3 positions and change in anterior segment biometric parameters after prophylactic laser peripheral iridotomy (LPI). Prospective clinical cohort study. Fifty-two eyes of 52 nonglaucomatous subjects with anatomically narrow angles. Anterior segment optical coherence tomography (ASOCT) images captured before and after LPI were analyzed using customized software, the Zhongshan Angle Assessment Program (ZAAP) (Zhongshan Ophthalmic Centre, Guangzhou, China). Differences in preoperative and postoperative measurements for anterior segment biometric parameters were compared by paired Student t tests. Multivariate linear regression models, adjusted for age, sex, ethnicity, and preoperative pupil diameter, were used to examine the association between the baseline measurements of iris thickness at 3 positions and the change in anterior segment biometric parameters after LPI. Baseline iris thickness measured at 750 μm from the scleral spur (IT750), iris thickness measured at 2000 μm from the scleral spur (IT2000), and maximal iris thickness (ITM). Changes in iris curvature (ICURV) and trabecular-iris space area at 500 μm from the scleral spur (TISA500) and 750 μm from the scleral spur (TISA750) after LPI. The ICURV significantly decreased, whereas TISA500 and TISA750 significantly increased after LPI (all P iris thickness are associated with greater decrease in ICURV and increases in TISA500 and TISA750 after LPI. This suggests that eyes with thinner irides undergoing LPI were more likely to exhibit greater magnitude of change in terms of flattening of the iris convexity (i.e., ICURV) and widening of the anterior chamber angle (i.e., TISA500 and TISA750). Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  17. Prototype multiwire proportional chamber

    CERN Multimedia

    1975-01-01

    Chambers of this type were initially developed within the Alpha project (finally not approved). They were designed such to minimize the radiation length with a view to a mass spectrometer of high resolution meant to replace the Omega detector. The chambers were clearly forerunners for the (drift) chambers later built for R606 with the novel technique of crimping the wires. See also photo 7510039X.

  18. Streamer chamber: pion decay

    CERN Multimedia

    1992-01-01

    The real particles produced in the decay of a positive pion can be seen in this image from a streamer chamber. Streamer chambers consist of a gas chamber through which a strong pulsed electric field is passed, creating sparks as a charged particle passes through it. A magnetic field is added to cause the decay products to follow curved paths so that their charge and momentum can be measured.

  19. Electromagnetic reverberation chambers

    CERN Document Server

    Besnier, Philippe

    2013-01-01

    Dedicated to a complete presentation on all aspects of reverberation chambers, this book provides the physical principles behind these test systems in a very progressive manner. The detailed panorama of parameters governing the operation of electromagnetic reverberation chambers details various applications such as radiated immunity, emissivity, and shielding efficiency experiments.In addition, the reader is provided with the elements of electromagnetic theory and statistics required to take full advantage of the basic operational rules of reverberation chambers, including calibration proc

  20. DORIOT CLIMATIC CHAMBERS

    Data.gov (United States)

    Federal Laboratory Consortium — The Doriot Climatic Chambers reproduce environmental conditions occurring anywhere around the world. They provide an invaluable service by significantly reducing the...

  1. Refrigeration Test Chamber

    Data.gov (United States)

    Federal Laboratory Consortium — The enclosed and environmentally controlled chamber is able to test four units (single-phase) simultaneously at conditions ranging from tundra to desert temperatures...

  2. Effects of primary selective laser trabeculoplasty on anterior segment parameters

    Directory of Open Access Journals (Sweden)

    Suzan Guven Yilmaz

    2015-10-01

    Full Text Available AIM:To investigate the effects of selective laser trabeculoplasty (SLT on the main numerical parameters of anterior segment with Pentacam rotating Scheimpflug camera in patients with ocular hypertension (OHT and primary open angle glaucoma (POAG.METHODS: Pentacam measurements of 45 eyes of 25 (15 females and 10 males patients (12 with OHT, 13 with POAG before and after SLT were obtained. Measurements were taken before and 1 and 3mo after SLT. Pentacam parameters were compared between OHT and POAG patients, and age groups (60y and older, and younger than 60y.RESULTS: The mean age of the patients was 57.8±13.9 (range 20-77y. Twelve patients (48% were younger than 60y, while 13 patients (52% were 60y and older. Measurements of pre-SLT and post-SLT 1mo were significantly different for the parameters of central corneal thickness (CCT and anterior chamber volume (ACV (P<0.05. These parameters returned back to pre-SLT values at post-SLT 3mo. Decrease of ACV at post-SLT 1mo was significantly higher in younger than 60y group than 60y and older group. There was no statistically significant difference in Pentacam parameters between OHT and POAG patients at pre- and post-treatment measurements (P>0.05.CONCLUSION:SLT leads to significant increase in CCT and decrease in ACV at the 1st month of the procedure. Effects of SLT on these anterior segment parameters, especially for CCT that interferes IOP measurement, should be considered to ensure accurate clinical interpretation.

  3. Goniodysgenesis in familial primary open-angle glaucoma

    NARCIS (Netherlands)

    Verbraak, F. D.; vd Berg, W.; Delleman, J. W.; Greve, E. L.

    1994-01-01

    Results of a pilot study to evaluate goniodysgenesis as a cause of familial open-angle glaucoma are reported. Patients with a familial high tension open-angle glaucoma and a goniodysgenetic chamber angle (n = 11), a number of their relatives with glaucoma (n = 12), and their relatives without

  4. Surgical technique for explantation of cosmetic anterior chamber iris implants.

    Science.gov (United States)

    Arjmand, Parnian; Gooi, Patrick; Ahmed, Iqbal Ike K

    2015-01-01

    The Newcoloriris is a silicone implant for cosmetic alteration of iris color. Implantation is associated with significant ocular complications of decreased vision, glaucoma, and corneal edema. Although removal of the implant also entails risks, it is ultimately necessary to preserve vision. We describe a technique for removing the implant that may also reduce intraoperative complications. The implant is explanted using a bimanual technique with small incisions in 3 sections via a "slicing-the-pie" technique using iris microforceps, microscissors, and microinstrumentation. Our patient required removal 5 years after implantation, which is the longest reported interval in the literature. This suggests that as long as these implants are present, ocular structures are at risk. 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.

  5. Ultrasound Biomicroscopic Evaluation of Uveal Effusion in Acute Primary Angle Closure.

    Science.gov (United States)

    You, Yi-an; Zhu, Le-ru; Wen, Ji-quan; Liu, Yin-he

    2015-12-01

    The aim of this study was to determine the prevalence of uveal effusion in acute primary angle closure (APAC), chronic primary angle-closure glaucoma (PACG), and primary open-angle glaucoma (POAG). A total of 152 consecutive patients (287 eyes) with APAC, PACG, and POAG were enrolled in this prospective and observational case series study. Intraocular pressure-lowering medications were used and ultrasound biomicroscopy examination was undertaken to determine the presence of uveal effusion and measure anterior chamber parameters. Overall, uveal effusion was evident in 40 of 194 affected eyes (20.6%) and no uveal effusion was seen in their fellow eyes. The prevalence of uveal effusion in APAC, chronic PACG, and POAG was 29.3%, 10.9%, and 3.1%, respectively (χ=226.63, PAPAC eyes had the highest prevalence of effusion and no effusion in their fellow eyes. In 40 eyes with uveal effusion, grade 1 effusion was seen in 17 eyes (42.5%), grade 2 in 15 eyes (37.5%), and grade 3 in 8 eyes (20%). In APAC eyes, the difference in the mean anterior chamber depth (ACD) among effusion grades 3, 2, and 1 was significant (F=5.425, P=0.017), and the eyes with grade 3 effusion had shallower ACD compared with grade 1 (P=0.031), but the difference was not significant compared with grade 2 (P=0.368). The eyes with APAC are associated with a higher prevalence of uveal effusion compared with PACG and POAG and probably as a result of rapid reduction in intraocular pressure with aggressive hypotensive therapy and inflammatory response to the process of acute attack.

  6. Climatic chamber ergometer

    CSIR Research Space (South Africa)

    Atkins, AR

    1968-01-01

    Full Text Available The design and calibration of an ergometer for exercising subjects during calorimetric studies in the climate chamber, are described. The ergometer is built into the climatic chamber and forms an integral part of the whole instrumentation system foe...

  7. bubble chamber lens

    CERN Multimedia

    Was used in a PS experiment. Before the days of electronic detectors, visual techniques were used to detect particles, using detectors such as spark chambers and bubble chambers. This plexiglass lens was used to focus the image of tracks so they could be photographed.

  8. BEBC bubble chamber

    CERN Multimedia

    CERN PhotoLab

    1972-01-01

    Looking up into the interior of BEBC bubble chamber from the expansion cylinder. At the top of the chamber two fish-eye lenses are installed and three other fish-eye ports are blanked off. In the centre is a heat exchanger.

  9. The Mobile Chamber

    Science.gov (United States)

    Scharfstein, Gregory; Cox, Russell

    2012-01-01

    A document discusses a simulation chamber that represents a shift from the thermal-vacuum chamber stereotype. This innovation, currently in development, combines the capabilities of space simulation chambers, the user-friendliness of modern-day electronics, and the modularity of plug-and-play computing. The Mobile Chamber is a customized test chamber that can be deployed with great ease, and is capable of bringing payloads at temperatures down to 20 K, in high vacuum, and with the desired metrology instruments integrated to the systems control. Flexure plans to lease Mobile Chambers, making them affordable for smaller budgets and available to a larger customer base. A key feature of this design will be an Apple iPad-like user interface that allows someone with minimal training to control the environment inside the chamber, and to simulate the required extreme environments. The feedback of thermal, pressure, and other measurements is delivered in a 3D CAD model of the chamber's payload and support hardware. This GUI will provide the user with a better understanding of the payload than any existing thermal-vacuum system.

  10. DELPHI time projection chamber

    CERN Document Server

    1989-01-01

    The time projection chamber is inserted inside the central detector of the DELPHI experiment. Gas is ionised in the chamber as a charged particle passes through, producing an electric signal from which the path of the particle can be found. DELPHI, which ran from 1989 to 2000 on the LEP accelerator, was primarily concerned with particle identification.

  11. Wafer scale oblique angle plasma etching

    Science.gov (United States)

    Burckel, David Bruce; Jarecki, Jr., Robert L.; Finnegan, Patrick Sean

    2017-05-23

    Wafer scale oblique angle etching of a semiconductor substrate is performed in a conventional plasma etch chamber by using a fixture that supports a multiple number of separate Faraday cages. Each cage is formed to include an angled grid surface and is positioned such that it will be positioned over a separate one of the die locations on the wafer surface when the fixture is placed over the wafer. The presence of the Faraday cages influences the local electric field surrounding each wafer die, re-shaping the local field to be disposed in alignment with the angled grid surface. The re-shaped plasma causes the reactive ions to follow a linear trajectory through the plasma sheath and angled grid surface, ultimately impinging the wafer surface at an angle. The selected geometry of the Faraday cage angled grid surface thus determines the angle at with the reactive ions will impinge the wafer.

  12. Valor de la ecobiometría en el glaucoma primario de ángulo estrecho Value of ecobiometry in the primary closed-angle glaucoma

    Directory of Open Access Journals (Sweden)

    Ibis Sedeño Cruz

    1999-06-01

    Full Text Available Se evalúa la importancia de la ecobiometría en el sistema diagnóstico del glaucoma primario de ángulo estrecho. A manera de ensayo clínico se estudiaron 105 ojos con esta enfermedad que se agruparon gonioscópicamente. Se les realizó ecobiometría como complemento diagnóstico. Se comprobó una relación directa de la amplitud de ángulo con la distancia axil y la profundidad de la cámara anterior y una relación inversa con el grosor del cristalino. Se observó que la profundidad de la cámara anterior menor de 2 mm constituye un alto riesgo para el desarrollo de un glaucoma agudo. El análisis ecobiométrico permitió conocer mejor el estado anatómico del ojo, facilitando una orientación terapéutica oportunaThe importance of ecobiometry for diagnosing primary closed-angle glaucoma is evaluated in this paper. 105 eyes with this diseases were clinically studied and gruoped according to the results of gonioscopy. Ecobiometry was performed as a diagnostic complement. A direct relationship between the exten of the angle and the axial distance and the depth of the anterior chamber was observed. An inversa relationship between the extent of the angle and the width of the crystalline lens was found. A depth of the anterior chamber under 2 mm is a high risk for the development of acute glaucoma. The ecobiometric analysis allowed to know the anatomical state of the eye better, making possible an opportune therapeutic guidance

  13. Anterior Horn Cell Diseases

    Directory of Open Access Journals (Sweden)

    Merve Firinciogullari

    2016-09-01

    Full Text Available The anterior horn cells control all voluntary movement. Motor activity, respiratory, speech, and swallowing functions are dependent upon signals from the anterior horn cells. Diseases that damage the anterior horn cells, therefore, have a profound impact. Symptoms of anterior horn cell loss (weakness, falling, choking lead patients to seek medical attention. In this article, anterior horn diseases were reviewed, diagnostic criteria and management were discussed in detail. [Archives Medical Review Journal 2016; 25(3.000: 269-303

  14. Plateau Iris Configuration and Dark-Light Changes in Anterior Segment Optical Coherence Tomography.

    Science.gov (United States)

    Ulaganathan, Sekar; Ganeshrao, Shonraj Ballae; Baskaran, Mani; Srinivasan, Sangeetha; Shantha, Ballekudru; Vijaya, Lingam

    2010-03-09

    The angle opening distance (AOD) was analyzed using anterior segment optical coherence tomography (ASOCT) in dark-light conditions in 14 convex iris configuration (CIC) and 12 plateau iris configuration (PIC) patients. AOD500 measured in dark and bright conditions in nasal quadrants were 0.156 +/- 0.072 mum; 0.186 +/- 0.084 mum for CIC (P = .025) and 0.177 +/- 0.121 mum; 0.186 +/- 0.116 mum for PIC (P = .38). AOD750 in dark and bright conditions in nasal quadrants were 0.235 +/- 0.082 mum; 0.280 +/- 0.097 mum for CIC (P = .000) and 0.294 +/- 0.181 mum; 0.306 +/- 0.172 mum for PIC. PIC showed no significant difference in the dynamic changes, whereas the nasal quadrant in CIC showed significant changes. The AOD parameters from ASOCT can be used to analyze the dark-light changes of the anterior chamber angle to differentiate between CIC and PICs. Copyright 2010, SLACK Incorporated.

  15. OPAL Jet Chamber Prototype

    CERN Multimedia

    OPAL was one of the four experiments installed at the LEP particle accelerator from 1989 - 2000. OPAL's central tracking system consists of (in order of increasing radius) a silicon microvertex detector, a vertex detector, a jet chamber, and z-chambers. All the tracking detectors work by observing the ionization of atoms by charged particles passing by: when the atoms are ionized, electrons are knocked out of their atomic orbitals, and are then able to move freely in the detector. These ionization electrons are detected in the dirfferent parts of the tracking system. This piece is a prototype of the jet chambers

  16. PS wire chamber

    CERN Document Server

    1970-01-01

    A wire chamber used at CERN's Proton Synchrotron accelerator in the 1970s. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  17. Ocular Biometry in Primary Angle-Closure Glaucoma Associated with Retinitis Pigmentosa

    Directory of Open Access Journals (Sweden)

    Jiangang Xu

    2017-01-01

    Full Text Available Background. Retinitis pigmentosa (RP comprises a group of inherited disorders in which patients typically lose night vision in adolescence and then lose peripheral vision in young adulthood before eventually losing central vision later in life. A retrospective case-control study was performed to evaluate differences in ocular biometric parameters in primary angle-closure glaucoma (PACG patients with and without concomitant RP to determine whether a relationship exists between PACG and RP. Methods. We used ultrasound biomicroscopy (UBM to measure anterior chamber depth (ACD. A-scan biometry was carried out to measure lens thickness (LT and axial length (AL. Propensity score matching and mixed linear regression model analysis were conducted. 23 patients with chronic primary angle-closure glaucoma (CPACG associated with RP, 21 patients with acute primary angle-closure glaucoma (APACG associated with RP, 270 patients with CPACG, and 269 patients with APACG were recruited for this study. Results. There were no significant differences on ACDs, ALs, and relative lens position (RLP (P>0.05 between patients with PACG associated with RP and patients with PACG; however, patients with APACG associated with RP had a significantly greater LT than patients with APACG (P<0.05. Conclusion. Patients with PACG associated with RP had the same biometric parameter characteristic as the patients with CPACG and APACG. This may suggest that RP is a coincidental relationship with angle-closure glaucoma.

  18. Management of intermittent angle closure glaucoma with Nd: yag laser iridotomy as a primary procedure

    International Nuclear Information System (INIS)

    Ahmed, M.

    2006-01-01

    To assess the efficacy and complications of Nd: YAG laser iridotomy in patients with intermittent (sub-acute) angle closure glaucoma. Twenty-five eyes of twenty-three patients with periodic (intermittent) angle closure, selected in outpatient department, were kept on pilocarpine until YAG laser iridotomy was performed. After YAG laser iridotomy oral acetazolamide and topical dexamethasone was used to control post laser rise of IOP and inflammation respectively. Patency of iridotomy was confirmed and intra-ocular pressure was measured one hour after the procedure. Immediate complication, if any, was noted. Follow-up was done for six months. Prophylactic laser iridotomy was done in fellow eye with occludable angle. Levene's test for equality of variance and t-test for equality of means were used for statistical analysis. This study revealed a significant difference in IOP before and after YAG laser iridotomy (p = .002). Complete follow-up of 6 months was possible in 25 eyes of 23 subjects. After YAG Laser iridotomy, 21 (84%) eyes showed negative provocative test, intraocular pressure below 19mm Hg without medication and anterior chamber angle no more occludable and were labeled successful. Iridotomy remained patent in 96% of eyes. Iridotomy failed to reduce IOP in 4 (16%) eyes. The complications were minimal and transient. (author)

  19. Peripheral iris thickness and association with iridotrabecular contact after laser peripheral iridotomy in patients with primary angle-closure and primary angle-closure glaucoma

    Directory of Open Access Journals (Sweden)

    Mizoguchi T

    2014-03-01

    Full Text Available Takanori Mizoguchi,1 Mineo Ozaki,2,3 Harumi Wakiyama,1,4 Nobuchika Ogino1,5 1Mizoguchi Eye Clinic, Sasebo, Japan; 2Ozaki Eye Clinic, Miyazaki, Japan; 3Department of Ophthalmology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan; 4Japanese Red Cross Nagasaki Genbaku Hospital, Nagasaki, Japan; 5Nishigaki Eye Clinic, Nagoya, Japan Purpose: To investigate the relation between the quantitative iris parameters and iridotrabecular contact (ITC in patients with primary angle-closure (PAC and PAC glaucoma (PACG. Materials and methods: PAC and PACG with laser peripheral iridotomy were recruited prospectively. Anterior-segment optical coherence tomography (ASOCT was performed under light and dark conditions, and scans were taken along the vertical and horizontal axes. Iris thickness at 500 µm (IT500 and 750 µm (IT750 from the scleral spur, maximal iris thickness (MIT, and cross sections of the iris area (I-Area were measured by using software. ITC was defined by the ASOCT as the contact between the peripheral iris and angle wall anterior to the scleral spur. The ITC+ and ITC- groups were defined as eyes that had ITC in two or more quadrants and in no or one quadrant, respectively. Results: A total of 79 eyes of 60 patients (consisting of 48 PAC and 31 PACG were recruited. The prevalence of superior, inferior, temporal, and nasal ITC was 44 eyes (55.7%, 48 eyes (60.8%, 18 eyes (22.8%, and 16 eyes (20.2%, respectively. These iris parameters of the inferior quadrant, which had the highest prevalence of all the quadrants, were used for the analysis. After adjusting for age, sex, pupil size, and central anterior chamber depth, mean values of IT500 and IT750 were significantly greater in the ITC+ group than the ITC- group (P<0.05. Multivariate-adjusted odds ratios of parameters for the ITC+ group compared with the ITC- group were: IT500, 1.9 (P=0.029; IT750, 2.0 (P=0.011, MIT, 1.4 (P=0.244, and I-Area, 0.97 (P=0.406, respectively, per 0.1-unit

  20. Miniature ionization chamber

    International Nuclear Information System (INIS)

    Alexeev, V.I.; Emelyanov, I.Y.; Ivanov, V.M.; Konstantinov, L.V.; Lysikov, B.V.; Postnikov, V.V.; Rybakov, J.V.

    1976-01-01

    A miniature ionization chamber having a gas-filled housing which accommodates a guard electrode made in the form of a hollow perforated cylinder is described. The cylinder is electrically associated with the intermediate coaxial conductor of a triaxial cable used as the lead-in of the ionization chamber. The gas-filled housing of the ionization chamber also accommodates a collecting electrode shaped as a rod electrically connected to the center conductor of the cable and to tubular members. The rod is disposed internally of the guard electrode and is electrically connected, by means of jumpers passing through the holes in the guard electrode, to the tubular members. The tubular members embrace the guard electrode and are spaced a certain distance apart along its entire length. Arranged intermediate of these tubular members are spacers secured to the guard electrode and fixing the collecting electrode throughout its length with respect to the housing of the ionization chamber

  1. Optical spark chamber

    CERN Multimedia

    CERN PhotoLab

    1971-01-01

    An optical spark chamber developed for use in the Omega spectrometer. On the left the supporting frame is exceptionally thin to allow low momentum particles to escape and be detected outside the magnetic field.

  2. ALICE Time Projection Chamber

    CERN Multimedia

    Lippmann, C

    2013-01-01

    The Time Projection Chamber (TPC) is the main device in the ALICE 'central barrel' for the tracking and identification (PID) of charged particles. It has to cope with unprecedented densities of charges particles.

  3. Vacuum chamber 'bicone'

    CERN Multimedia

    1977-01-01

    This chamber is now in the National Museum of History and Technology, Smithsonian Institution, Washington, DC, USA, where it was exposed in an exhibit on the History of High Energy Accelerators (1977).

  4. Gridded Ionization Chamber

    International Nuclear Information System (INIS)

    Manero Amoros, F.

    1962-01-01

    In the present paper the working principles of a gridded ionization chamber are given, and all the different factors that determine its resolution power are analyzed in detail. One of these devices, built in the Physics Division of the JEN and designed specially for use in measurements of alpha spectroscopy, is described. finally the main applications, in which the chamber can be used, are shown. (Author) 17 refs

  5. Bubble chamber: antiproton annihilation

    CERN Multimedia

    1971-01-01

    These images show real particle tracks from the annihilation of an antiproton in the 80 cm Saclay liquid hydrogen bubble chamber. A negative kaon and a neutral kaon are produced in this process, as well as a positive pion. The invention of bubble chambers in 1952 revolutionized the field of particle physics, allowing real tracks left by particles to be seen and photographed by expanding liquid that had been heated to boiling point.

  6. Sleeve reaction chamber system

    Science.gov (United States)

    Northrup, M Allen [Berkeley, CA; Beeman, Barton V [San Mateo, CA; Benett, William J [Livermore, CA; Hadley, Dean R [Manteca, CA; Landre, Phoebe [Livermore, CA; Lehew, Stacy L [Livermore, CA; Krulevitch, Peter A [Pleasanton, CA

    2009-08-25

    A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

  7. Differences between fellow eyes of acute and chronic primary angle closure (glaucoma: An ultrasound biomicroscopy quantitative study.

    Directory of Open Access Journals (Sweden)

    Mengwei Li

    Full Text Available To compare various biometric parameters between fellow eyes of acute primary angle closure (glaucoma [APAC(G] and fellow eyes of chronic primary angle closure (glaucoma [CPAC(G].Ultrasound biomicroscopy examinations were performed on 47 patients with unilateral APAC(G and 41 patients with asymmetric CPAC(G before laser peripheral iridotomy and pilocarpine treatment. Anterior chamber depth and width (ACD and ACW, lens vault (LV, iris curvature (IC, iris root distance (IRD, trabecular-ciliary process distance (TCPD, iris-ciliary process distance (ICPD, trabecular-ciliary angle (TCA, and other biometric parameters were compared between fellow eyes of APAC(G and fellow eyes of CAPC(G.Compared with fellow eyes of CPAC(G, fellow eyes of APAC(G had smaller ACD (P < 0.001, ACW (P = 0.007, TCPD (P = 0.016, ICPD (P = 0.008, and TCA (P = 0.006, as well as larger LV (P = 0.002, IC (P = 0.012, and IRD (P = 0.003. On multivariate logistic regression analyses, a 0.1 mm decrease in ACD (odds ratio [OR]: 0.705, 95%CI: 0.564-0.880, P = 0.002, ICPD (OR: 0.557, 95%CI: 0.335-0.925, P = 0.024, and a 0.1 mm increase in IRD (OR: 2.707, 95%CI: 1.025-7.149, P = 0.045, was significantly associated with occurrence of acute angle closures.Fellow eyes of APAC(G had smaller anterior segment dimensions, higher LV, more posterior iris insertion, greater IC, and more anteriorly rotated ciliary body compared with fellow eyes of CPAC(G. ACD, ICPD, and IRD were the three most important parameters that distinguish eyes predisposed to APAC(G or CPAC(G.

  8. Oseltamivir (Tamiflu-induced bilateral acute angle closure glaucoma and transient myopia

    Directory of Open Access Journals (Sweden)

    Ji Woong Lee

    2014-01-01

    Full Text Available A 27-year-old woman developed bilateral acute angle closure glaucoma (AACG and transient myopia after taking oseltamivir for four days. On the fourth day, she received systemic and topical intraocular pressure (IOP-lowering agents, and IOP decreased in both eyes. However, her visual acuity was unchanged. A myopic shift of -5.25 D OD and -5.0 D OS was estimated to have occurred in the acute phase. A-scan ultrasonography and Pentacam showed markedly shallow anterior chambers and increased lens thickness. Ultrasound biomicroscopy revealed an annular ciliochoroidal effusion with forward displacement of the lens-iris diaphragm. Ciliochoroidal effusion and transient myopia were resolved after discontinuation of oseltamivir.

  9. DELPHI Barrel Muon Chamber Module

    CERN Multimedia

    1989-01-01

    The module was used as part of the muon identification system on the barrel of the DELPHI detector at LEP, and was in active use from 1989 to 2000. The module consists of 7 individual muons chambers arranged in 2 layers. Chambers in the upper layer are staggered by half a chamber width with respect to the lower layer. Each individual chamber is a drift chamber consisting of an anode wire, 47 microns in diameter, and a wrapped copper delay line. Each chamber provided 3 signal for each muon passing through the chamber, from which a 3D space-point could be reconstructed.

  10. The KLOE drift chamber

    CERN Document Server

    Adinolfi, M; Ambrosino, F; Andryakov, A; Antonelli, A; Antonelli, M; Anulli, F; Bacci, C; Bankamp, A; Barbiellini, G; Bellini, F; Bencivenni, G; Bertolucci, Sergio; Bini, C; Bloise, C; Bocci, V; Bossi, F; Branchini, P; Bulychjov, S A; Cabibbo, G; Calcaterra, A; Caloi, R; Campana, P; Capon, G; Carboni, G; Cardini, A; Casarsa, M; Cataldi, G; Ceradini, F; Cervelli, F; Cevenini, F; Chiefari, G; Ciambrone, P; Conetti, S; Conticelli, S; Lucia, E D; Robertis, G D; Sangro, R D; Simone, P D; Zorzi, G D; Dell'Agnello, S; Denig, A; Domenico, A D; Donato, C D; Falco, S D; Doria, A; Drago, E; Elia, V; Erriquez, O; Farilla, A; Felici, G; Ferrari, A; Ferrer, M L; Finocchiaro, G; Forti, C; Franceschi, A; Franzini, P; Gao, M L; Gatti, C; Gauzzi, P; Giovannella, S; Golovatyuk, V; Gorini, E; Grancagnolo, F; Grandegger, W; Graziani, E; Guarnaccia, P; Von Hagel, U; Han, H G; Han, S W; Huang, X; Incagli, M; Ingrosso, L; Jang, Y Y; Kim, W; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Lomtadze, F; Luisi, C; Mao Chen Sheng; Martemyanov, M; Matsyuk, M; Mei, W; Merola, L; Messi, R; Miscetti, S; Moalem, A; Moccia, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nedosekin, A; Panareo, M; Pacciani, L; Pagès, P; Palutan, M; Paoluzi, L; Pasqualucci, E; Passalacqua, L; Passaseo, M; Passeri, A; Patera, V; Petrolo, E; Petrucci, Guido; Picca, D; Pirozzi, G; Pistillo, C; Pollack, M; Pontecorvo, L; Primavera, M; Ruggieri, F; Santangelo, P; Santovetti, E; Saracino, G; Schamberger, R D; Schwick, C; Sciascia, B; Sciubba, A; Scuri, F; Sfiligoi, I; Shan, J; Silano, P; Spadaro, T; Spagnolo, S; Spiriti, E; Stanescu, C; Tong, G L; Tortora, L; Valente, E; Valente, P; Valeriani, B; Venanzoni, G; Veneziano, Stefano; Wu, Y; Xie, Y G; Zhao, P P; Zhou, Y

    2001-01-01

    The tracking detector of the KLOE experiment is 4 m diameter, 3.3 m length drift chamber, designed to contain a large fraction of the decays of low-energy K sub L produced at the Frascati DAPHINE phi-factory. The chamber is made by a thin carbon fiber structure and operated with a helium-based gas mixture in order to minimise conversion of low-energy photons and multiple scattering inside the sensitive volume. The tracking information is provided by 58 layers of stereo wires defing 12,582 cells, 2x2 cm sup 2 in size in the 12 innermost layers and 3x3 cm sup 2 in the outer ones. Details of the chamber design, calibration procedure and tracking performances are presented.

  11. The KLOE drift chamber

    International Nuclear Information System (INIS)

    Adinolfi, M.; Aloisio, A.; Ambrosino, F.; Andryakov, A.; Antonelli, A.; Antonelli, M.; Anulli, F.; Bacci, C.; Bankamp, A.; Barbiellini, G.; Bellini, F.; Bencivenni, G.; Bertolucci, S.; Bini, C.; Bloise, C.; Bocci, V.; Bossi, F.; Branchini, P.; Bulychjov, S.A.; Cabibbo, G.; Calcaterra, A.; Caloi, R.; Campana, P.; Capon, G.; Carboni, G.; Cardini, A.; Casarsa, M.; Cataldi, G.; Ceradini, F.; Cervelli, F.; Cevenini, F.; Chiefari, G.; Ciambrone, P.; Conetti, S.; Conticelli, S.; Lucia, E. De; Robertis, G. De; Sangro, R. De; Simone, P. De; Zorzi, G. De; Dell'Agnello, S.; Denig, A.; Domenico, A. Di; Donato, C. Di; Falco, S. Di; Doria, A.; Drago, E.; Elia, V.; Erriquez, O.; Farilla, A.; Felici, G.; Ferrari, A.; Ferrer, M.L.; Finocchiaro, G.; Forti, C.; Franceschi, A.; Franzini, P.; Gao, M.L.; Gatti, C.; Gauzzi, P.; Giovannella, S.; Golovatyuk, V.; Gorini, E.; Grancagnolo, F.; Grandegger, W.; Graziani, E.; Guarnaccia, P.; Hagel, U.V.; Han, H.G.; Han, S.W.; Huang, X.; Incagli, M.; Ingrosso, L.; Jang, Y.Y.; Kim, W.; Kluge, W.; Kulikov, V.; Lacava, F.; Lanfranchi, G.; Lee-Franzini, J.; Lomtadze, F.; Luisi, C.; Mao, C.S.; Martemianov, M.; Matsyuk, M.; Mei, W.; Merola, L.; Messi, R.; Miscetti, S.; Moalem, A.; Moccia, S.; Moulson, M.; Mueller, S.; Murtas, F.; Napolitano, M.; Nedosekin, A.; Panareo, M.; Pacciani, L.; Pages, P.; Palutan, M.; Paoluzi, L.; Pasqualucci, E.; Passalacqua, L.; Passaseo, M.; Passeri, A.; Patera, V.; Petrolo, E.; Petrucci, G.; Picca, D.; Pirozzi, G.; Pistillo, C.; Pollack, M.; Pontecorvo, L.; Primavera, M.; Ruggieri, F.; Santangelo, P.; Santovetti, E.; Saracino, G.; Schamberger, R.D.; Schwick, C.; Sciascia, B.; Sciubba, A.; Scuri, F.; Sfiligoi, I.; Shan, J.; Silano, P.; Spadaro, T.; Spagnolo, S.; Spiriti, E.; Stanescu, C.; Tong, G.L.; Tortora, L.; Valente, E.; Valente, P.; Valeriani, B.; Venanzoni, G.; Veneziano, S.; Wu, Y.; Xie, Y.G.; Zhao, P.P.; Zhou, Y.

    2001-01-01

    The tracking detector of the KLOE experiment is 4 m diameter, 3.3 m length drift chamber, designed to contain a large fraction of the decays of low-energy K L produced at the Frascati DAPHINE phi-factory. The chamber is made by a thin carbon fiber structure and operated with a helium-based gas mixture in order to minimise conversion of low-energy photons and multiple scattering inside the sensitive volume. The tracking information is provided by 58 layers of stereo wires defing 12,582 cells, 2x2 cm 2 in size in the 12 innermost layers and 3x3 cm 2 in the outer ones. Details of the chamber design, calibration procedure and tracking performances are presented

  12. Multiple chamber ionization detector

    International Nuclear Information System (INIS)

    Solomon, E.E.

    1982-01-01

    An ionization smoke detector employs a single radiation source in a construction comprising at least two chambers with a center or node electrode. The radioactive source is associated with this central electrode, and its positioning may be adjusted relative to the electrode to alter the proportion of the source that protrudes into each chamber. The source may also be mounted in the plane of the central electrode, and positioned relative to the center of the electrode. The central electrode or source may be made tiltable relative to the body of the detector

  13. micro strip gas chamber

    CERN Multimedia

    1998-01-01

    About 16 000 Micro Strip Gas Chambers like this one will be used in the CMS tracking detector. They will measure the tracks of charged particles to a hundredth of a millimetre precision in the region near the collision point where the density of particles is very high. Each chamber is filled with a gas mixture of argon and dimethyl ether. Charged particles passing through ionise the gas, knocking out electrons which are collected on the aluminium strips visible under the microscope. Such detectors are being used in radiography. They give higher resolution imaging and reduce the required dose of radiation.

  14. Charpak hemispherical wire chamber

    CERN Document Server

    1970-01-01

    pieces. Mesures are of the largest one. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  15. Effects of twisting of the graft in anterior cruciate ligament reconstruction

    NARCIS (Netherlands)

    Elmans, L.; Wymenga, A.; van Kampen, A.; van der Wielen, P.; Mommersteeg, T. J. A.; Blankevoort, L.

    2003-01-01

    In an in vitro study on six knees from cadavers, the effect of bone-patellar tendon-bone graft twist on anterior knee laxity was measured at different knee flexion angles. A motion and loading rig was used to prescribe the flexion angle, to restrain axial rotation, and to apply 100 N anterior force

  16. Correction effect of phakic posterior chamber implantable contact lens implantation on high myopia

    Directory of Open Access Journals (Sweden)

    Jing Wang

    2018-02-01

    Full Text Available AIM: To analyze the clinical efficacy of phakic posterior chamber implantable contact lens(ICLimplantation on high myopia patients. METHODS: Thirty-four patients(68 eyeswho checked and diagnosed as high myopia in our hospital from June 2014 to June 2015 were selected as the clinical research subjects, and all the patients were given phakic posterior chamber intraocular lens implantation treatment. The diopter, visual acuity recovery, central anterior chamber depth, corneal endothelial cell count, and intraocular pressure after treatment were observed. RESULTS: The equivalent spherical refraction, central anterior chamber depth, uncorrected visual acuity and best corrected visual acuity recovery at 1, 3 and 6mo, 1 and 2a after treatment were better than those before treatment, and the differences were statistically significant(PP>0.05. There were no significant differences in uncorrected visual acuity, best corrected visual acuity, equivalent spherical refraction and central anterior chamber depth at 1, 3mo and 1 and 2a after treatment(P>0.05. CONCLUSION: The application of phakic posterior chamber intraocular lens implantation for the treatment of high myopia patients can improve the equivalent spherical refraction and central anterior chamber depth, improve uncorrected visual acuity, meanwhile, it has less effect on the patient's intraocular pressure and corneal endometrial cells, the effect maintenance and safety is better which meet their expectations.

  17. Large planar drift chambers

    CERN Document Server

    Marel, Gérard; Bréhin, S; Devaux, B; Diamant-Berger, Alain M; Leschevin, C; Maillard, J; Malbequi, Y; Martin, H; Patoux, A; Pelle, J; Plancoulaine, J; Tarte, Gérard; Turlay, René

    1977-01-01

    The authors describe 14 m/sup 2/ hexagonal planar drift chambers designed for the neutrino experiment of the CERN-Dortmund-Heidelberg- Saclay Collaboration. Details on mechanical construction, electronic read-out, results on efficiency and accuracy are presented. (6 refs).

  18. Improvements in ionization chambers

    International Nuclear Information System (INIS)

    Whetten, N.R.; Zubal, C.

    1980-01-01

    A method of reducing mechanical vibrations transmitted to the parallel plate electrodes of ionization chamber x-ray detectors, commonly used in computerized x-ray axial tomography systems, is described. The metal plate cathodes and anodes are mounted in the ionizable gas on dielectric sheet insulators consisting of a composite of silicone resin and glass fibres. (UK)

  19. LEP vacuum chamber, prototype

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    Final prototype for the LEP vacuum chamber, see 8305170 for more details. Here we see the strips of the NEG pump, providing "distributed pumping". The strips are made from a Zr-Ti-Fe alloy. By passing an electrical current, they were heated to 700 deg C.

  20. Review of straw chambers

    International Nuclear Information System (INIS)

    Toki, W.H.

    1990-03-01

    This is a review of straw chambers used in the HRS, MAC, Mark III, CLEO, AMY, and TPC e + e - experiments. The straws are 6--8 mm in diameter, operate at 1--4 atmospheres and obtain resolutions of 45--100 microns. The designs and constructions are summarized and possible improvements discussed

  1. Heavy liquid bubble chamber

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    The CERN Heavy liquid bubble chamber being installed in the north experimental hall at the PS. On the left, the 1180 litre body; in the centre the magnet, which can produce a field of 26 800 gauss; on the right the expansion mechanism.

  2. LEP Vacuum Chamber

    CERN Multimedia

    1983-01-01

    This is a cut-out of a LEP vacuum chamber for dipole magnets showing the beam channel and the pumping channel with the getter (NEG) strip and its insulating supports. A water pipe connected to the cooling channel can also be seen at the back.The lead radiation shield lining is also shown. See also 8305563X.

  3. MISSING: BUBBLE CHAMBER LENS

    CERN Multimedia

    2001-01-01

    Would the person who borrowed the large bubble chamber lens from the Microcosm workshops on the ISR please return it. This is a much used piece from our object archives. If anybody has any information about the whereabouts of this object, please contact Emma.Sanders@cern.ch Thank you

  4. Scanning bubble chamber pictures

    CERN Multimedia

    1974-01-01

    These were taken at the 2 m hydrogen bubble chamber. The photo shows an early Shiva system where the pre-measurements needed to qualify the event were done manually (cf photo 7408136X). The scanning tables were located in bld. 12. Gilberte Saulmier sits on foreground, Inge Arents at centre.

  5. Chamber Profile Measurement System.

    Science.gov (United States)

    1980-10-01

    travel with the proper electronics. Other features of tihe gage assembly are: 1. Micrometer controlled down chamber positioning of the master template to...pressure sensitive "stiff stick" for infinitely varying the rate of travel from zero to maximum. A manual vernier control is incorporated to permit fine

  6. Drift chamber detectors

    International Nuclear Information System (INIS)

    Duran, I.; Martinez Laso, L.

    1989-01-01

    A review of High Energy Physics detectors based on drift chambers is presented. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysied, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author)

  7. Drift Chambers detectors

    International Nuclear Information System (INIS)

    Duran, I.; Martinez laso, L.

    1989-01-01

    We present here a review of High Energy Physics detectors based on drift chambers. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysed, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author) 115 refs

  8. The KLOE drift chamber

    International Nuclear Information System (INIS)

    Ferrari, A.

    2002-01-01

    The design and construction of the large drift chamber of the KLOE experiment is presented. The track reconstruction is described, together with the calibration method and the monitoring systems. The stability of operation and the performance are studied with samples of e + e - , K S K L and K + K - events

  9. Liquid Wall Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Meier, W R

    2011-02-24

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  10. Wire chamber conference

    International Nuclear Information System (INIS)

    Bartl, W.; Neuhofer, G.; Regler, M.

    1986-02-01

    This booklet contains program and the abstracts of the papers presented at the conference, most of them dealing with performance testing of various types of wire chambers. The publication of proceedings is planned as a special issue of 'Nuclear instruments and methods' later on. All abstracts are in English. An author index for the book of abstracts is given. (A.N.)

  11. CLINICAL STUDY OF POSTERIOR CHAMBER PHAKIC IOL PLACEMENT IN MYOPIC PATIENTS

    Directory of Open Access Journals (Sweden)

    Ashok Kumar P

    2017-02-01

    Full Text Available BACKGROUND The aim of this study was to determine the safety and efficacy of posterior chamber phakic IOL in Myopic patients. MATERIALS AND METHODS This prospective interventional study included 50 eyes of 50 patients with myopia. Patients of age more than 18 yrs. Stable refraction, Myopia, Mild to Moderate keratoconus and absence of any ocular pathology and any history of ocular surgeries were included in this study. Prior to starting treatment certain parameters like visual acuity, AC depth, Iridocorneal Angle Aperture, Endothelial cell count, Central corneal thickness and IOP were considered. Intervention- Implantation of the phakic IOL. Main outcome Measures- Uncorrected Visual Acuity (UCVA, best spectacle corrected visual acuity (BSCVA, AS OCT AC depthbetween endothelium and phakic IOL, IOP and Endothelial cell count were recorded. RESULTS Postoperative examinations conducted at day 1, day 3, after 1 week, 1 month and after 3 months .out of 50 patients, 4 patients had striate keratopathy, 2 patients had shallow ac during immediate post-operative period. During the postoperative follow up 10 patients had BCVA of 6/9-6/6 (20%, 14 patients had 6/9-6/12 (28%, 24 patients had 6/12-6/24(48% and remaining 2 patients had <6/24 which was better than their preoperative uncorrected visual acuity. CONCLUSION Based on this prospective clinical study and on comparison with other clinical studies posterior chamber phakic IOL corrective procedures are safe and effective for treatment of myopia. It also shows that it can provide sharp and clear vision in 96% of our study population. It does not induce dry eye syndrome as in other refractive surgeries. Short term complications like endothelial damage, angle closure glaucoma, iritis, anterior capsule injury/lens changes were not encountered during our study. But still long term follow up is required to confirm long term safety of the implant.

  12. Anterior Segment Ischemia after Strabismus Surger

    Directory of Open Access Journals (Sweden)

    Emine Seyhan Göçmen

    2017-01-01

    Full Text Available A 46-year-old male patient was referred to our clinic with complaints of diplopia and esotropia in his right eye that developed after a car accident. The patient had right esotropia in primary position and abduction of the right eye was totally limited. Primary deviation was over 40 prism diopters at near and distance. The patient was diagnosed with sixth nerve palsy and 18 months after trauma, he underwent right medial rectus muscle recession. Ten months after the first operation, full-thickness tendon transposition of the superior and inferior rectus muscles (with Foster suture was performed. On the first postoperative day, slit-lamp examination revealed corneal edema, 3+ cells in the anterior chamber and an irregular pupil. According to these findings, the diagnosis was anterior segment ischemia. Treatment with 0.1/5 mL topical dexamethasone drops (16 times/day, cyclopentolate hydrochloride drops (3 times/day and 20 mg oral fluocortolone (3 times/day was initiated. After 1 week of treatment, corneal edema regressed and the anterior chamber was clean. Topical and systemic steroid treatment was gradually discontinued. At postoperative 1 month, the patient was orthophoric and there were no pathologic symptoms besides the irregular pupil. Anterior segment ischemia is one of the most serious complications of strabismus surgery. Despite the fact that in most cases the only remaining sequel is an irregular pupil, serious circulation deficits could lead to phthisis bulbi. Clinical properties of anterior segment ischemia should be well recognized and in especially risky cases, preventative measures should be taken.

  13. CONGENITAL ANTERIOR TIBIOFEMURAL SUBLUXATION

    Directory of Open Access Journals (Sweden)

    A. Shahla

    2008-06-01

    Full Text Available Congenital anterior tibiofemoral subluxation is an extremely rare disorder. All reported cases accompanied by other abnormalities and syndromes. A 16-year-old high school girl referred to us with bilateral anterior tibiofemoral subluxation as the knees were extended and reduced at more than 30 degrees flexion. Deformities were due to tightness of the iliotibial band and biceps femuris muscles and corrected by surgical release. Associated disorders included bilateral anterior shoulders dislocation, short metacarpals and metatarsals, and right calcaneuvalgus deformity.

  14. Wire chamber gases

    International Nuclear Information System (INIS)

    Va'vra, J.

    1992-04-01

    In this paper, we describe new developments in gas mixtures which have occurred during the last 3--4 years. In particular, we discuss new results on the measurement and modeling of electron drift parameters, the modeling of drift chamber resolution, measurements of primary ionization and the choice of gas for applications such as tracking, single electron detection, X-ray detection and visual imaging. In addition, new results are presented on photon feedback, breakdown and wire aging

  15. Vienna Wire Chamber Conference

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    After those of 1978 and 1980, a third Wire Chamber Conference was held from 15-18 February in the Technical University of Vienna. Eight invited speakers covered the field from sophisticated applications in biology and medicine, via software, to the state of the art of gaseous detectors. In some forty other talks the speakers tackled in more detail the topics of gaseous detectors, calorimetry and associated electronics and software

  16. Double chambered right ventricle

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chul Koo; Yu, Yun Jeong; Yeon, Kyung Mo; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1983-12-15

    Fourteen cases of double chambered right ventricle were diagnosed angiographically and of these nine cases were confirmed after operation and autopsy at Seoul National University Hospital in recent four years since 1979. The clinical and radiological findings with the emphasis on the cinecardiographic findings were analysed. The summaries of the analysis are as follows: 1. Among 14 cases, 6 cases were male and 8 cases were female. Age distribution was from 4 years to 36 years. 2. In chest x-ray findings, pulmonary vascularity was increased in 8 cases, decreased in 4 cases, and normal in 2 cases. Cardiomegaly was observed in 8 cases and other showed normal heart size. 3. In cinecardiography, 11 cases had interventricular septal defect. Among these 11 cases, VSD located in proximal high pressure chamber was in 2 cases and located in distal low pressure chamber was in 9 cases. 4. The location of aberrant muscle bundle in sinus portion of right ventricle was in 8 cases. In the rest 6 cases, the aberrant muscle bundle was located below the infundibulum of right ventricle. 5. For accurate diagnosis and differential diagnosis with other congenital cardiac anomalies such as Tetralogy of Fallot or isolated pulmonic stenosis, biplane cineangiography and catheterization is an essential procedure.

  17. Double chambered right ventricle

    International Nuclear Information System (INIS)

    Cho, Chul Koo; Yu, Yun Jeong; Yeon, Kyung Mo; Han, Man Chung

    1983-01-01

    Fourteen cases of double chambered right ventricle were diagnosed angiographically and of these nine cases were confirmed after operation and autopsy at Seoul National University Hospital in recent four years since 1979. The clinical and radiological findings with the emphasis on the cinecardiographic findings were analysed. The summaries of the analysis are as follows: 1. Among 14 cases, 6 cases were male and 8 cases were female. Age distribution was from 4 years to 36 years. 2. In chest x-ray findings, pulmonary vascularity was increased in 8 cases, decreased in 4 cases, and normal in 2 cases. Cardiomegaly was observed in 8 cases and other showed normal heart size. 3. In cinecardiography, 11 cases had interventricular septal defect. Among these 11 cases, VSD located in proximal high pressure chamber was in 2 cases and located in distal low pressure chamber was in 9 cases. 4. The location of aberrant muscle bundle in sinus portion of right ventricle was in 8 cases. In the rest 6 cases, the aberrant muscle bundle was located below the infundibulum of right ventricle. 5. For accurate diagnosis and differential diagnosis with other congenital cardiac anomalies such as Tetralogy of Fallot or isolated pulmonic stenosis, biplane cineangiography and catheterization is an essential procedure

  18. Argus target chamber

    International Nuclear Information System (INIS)

    Rienecker, F. Jr.; Glaros, S.S.; Kobierecki, M.

    1975-01-01

    A target chamber for application in the laser fusion program must satisfy some very basic requirements. (1) Provide a vacuum on the order of 10 -6 torr. (2) Support a microscopically small target in a fixed point in space and verify its location within 5 micrometers. (3) Contain an adjustable beam focusing system capable of delivering a number of laser beams onto the target simultaneously, both in time and space. (4) Provide access for diagnostics to evaluate the results of target irradiation. (5) Have flexibility to allow changes in targets, focusing optics and number of beams. The ARGUS laser which is now under construction at LLL will have a target chamber which meets these requirements in a simple economic manner. The chamber and auxiliary equipment are described, with reference to two double beam focusing systems; namely, lenses and ellipsoidal mirrors. Provision is made for future operation with four beams, using ellipsoidal mirrors for two-sided illumination and lens systems for tetragonal and tetrahedral irradiation

  19. Wire chambers: Trends and alternatives

    International Nuclear Information System (INIS)

    Regler, Meinhard

    1992-01-01

    The subtitle of this year's Vienna Wire Chamber Conference - 'Recent Trends and Alternative Techniques' - signalled that it covered a wide range of science and technology. While an opening Vienna talk by wire chamber pioneer Georges Charpak many years ago began 'Les funerailles des chambres a fils (the burial of wire chambers)', the contrary feeling this year was that wire chambers are very much alive!

  20. Criteria for controlled atmosphere chambers

    International Nuclear Information System (INIS)

    Robinson, J.N.

    1980-03-01

    The criteria for design, construction, and operation of controlled atmosphere chambers intended for service at ORNL are presented. Classification of chambers, materials for construction, design criteria, design, controlled atmosphere chamber systems, and operating procedures are presented. ORNL Safety Manual Procedure 2.1; ORNL Health Physics Procedure Manual Appendix A-7; and Design of Viewing Windows are included in 3 appendices

  1. Anterior ankle impingement

    NARCIS (Netherlands)

    Tol, Johannes L.; van Dijk, C. Niek

    2006-01-01

    The anterior ankle impingement syndrome is a clinical pain syndrome that is characterized by anterior ankle pain on (hyper) dorsiflexion. The plain radiographs often are negative in patients who have anteromedial impingement. An oblique view is recommended in these patients. Arthroscopic excision of

  2. Effects of two different deep digital flexor tenotomy techniques on distal articular angles of equine cadaver forelimbs Efeito de duas técnicas de tenotomia do flexor digital profundo sobre os ângulos articulares distais dos membros anteriores de equinos: estudo post-mortem

    Directory of Open Access Journals (Sweden)

    Antonio Cezar de Oliveira Dearo

    2012-11-01

    Full Text Available Deep digital flexor (DDF tenotomy is a technique employed for years to treat selected disorders of the musculoskeletal system in horses. Although two different surgical approaches (i.e. mid-metacarpal and pastern have been described for performing the procedure, in vitro quantitative data regarding the modifications induced by either technique on the distal articular angles is lacking. Therefore, the purpose of the study reported here was to investigate the viability of a proposed biomechanical system of induced-traction used to compare the two DDF tenotomy techniques by measuring the distal articular angles of equine cadaver forelimbs. Ten pairs of forelimbs were collected and mounted to a biomechanical system developed to apply traction at the toe level. Dorsal articular angles of the metacarpophalangeal (MP, proximal interphalangeal (PIP and distal interphalangeal (DIP joints were determined by geometric lines on radiographs taken before and after performing each technique. Comparisons between each tenotomy group and its own control, for each joint, and between the two tenotomy groups using as variable the difference between the tenotomy and control groups were tested. Despite the lack of statistical significance, the DDF tenotomy technique at the pastern level produced extension, to a lesser and greater extent, of the PIP and DIP joints, respectively when compared to the mid-metacarpal level. No remarkable differences could be observed for the MP joint. The developed traction-induced biomechanical construct seemed to be effective in producing valuable quantitative estimations of the distal articular angles of equine cadaver forelimbs subjected to different DDF tenotomy techniques.A tenotomia do flexor digital profundo (FDP é uma das técnicas cirúrgicas empregadas para o tratamento de algumas anormalidades osteomusculares, como as deformidades flexurais e a laminite em equinos. Embora diferentes acessos cirúrgicos (i.e. terço médio do

  3. Vacuum Chambers for LEP sections

    CERN Multimedia

    1983-01-01

    The picture shows sections of the LEP vacuum chambers to be installed in the dipole magnets (left) and in the quadrupoles (right). The dipole chamber has three channels: the beam chamber, the pumping duct where the NEG (non-evaporabe getter) is installed and the water channel for cooling (on top in the picture). The pumping duct is connected to the beam chamber through holes in the separating wall. The thick lead lining to shield radiation can also be seen. These chambers were manufactured as extruded aluminium alloy profiles.

  4. A compact high vacuum heating chamber for in-situ x-ray scattering studies.

    Science.gov (United States)

    Bertram, F; Deiter, C; Pflaum, K; Seeck, O H

    2012-08-01

    A very compact multi purpose high vacuum heating chamber for x-ray scattering techniques was developed. The compact design allows the chamber to be installed on high precision diffractometers which usually cannot support heavy and/or large equipment. The chamber is covered by a Be dome allowing full access to the hemisphere above the sample which is required for in-plane grazing incident x-ray diffraction and out-off plane wide angle x-ray diffraction.

  5. A compact high vacuum heating chamber for in-situ x-ray scattering studies

    Energy Technology Data Exchange (ETDEWEB)

    Bertram, F.; Deiter, C.; Pflaum, K.; Seeck, O. H. [Hamburger Synchrotronstrahlungslabor am Deutschen Elektronen-Synchrotron, Notkestr. 85, 22607 Hamburg (Germany)

    2012-08-15

    A very compact multi purpose high vacuum heating chamber for x-ray scattering techniques was developed. The compact design allows the chamber to be installed on high precision diffractometers which usually cannot support heavy and/or large equipment. The chamber is covered by a Be dome allowing full access to the hemisphere above the sample which is required for in-plane grazing incident x-ray diffraction and out-off plane wide angle x-ray diffraction.

  6. Cataract Surgery in Anterior Megalophthalmos: A Review

    Science.gov (United States)

    GALVIS, Virgilio; TELLO, Alejandro; M. RANGEL, Carlos

    2015-01-01

    Anterior megalophthalmos is characterized by megalocornea associated with a very broad anterior chamber and ciliary ring elongation. It is also called X-linked megalocornea. It is accompanied by early development of cataracts, zonular anomalies, and, rarely, vitreoretinal disorders. Subluxation of a cataract can occur in cataract surgery because of zonular weakness. In addition, in most patients, standard intraocular lens (IOL) decentration is a risk because of the enlarged sulcus and capsular bag. These unique circumstances make cataract surgery challenging. To date, several approaches have been developed. Implantation of a retropupillary iris-claw aphakic intraocular lens may be a good option because it is easier than suturing the IOL and can have better and more stable anatomic and visual outcomes, compared to other techniques. PMID:27350950

  7. Space plasma simulation chamber

    International Nuclear Information System (INIS)

    1986-01-01

    Scientific results of experiments and tests of instruments performed with the Space Plasma Simulation Chamber and its facility are reviewed in the following six categories. 1. Tests of instruments on board rockets, satellites and balloons. 2. Plasma wave experiments. 3. Measurements of plasma particles. 4. Optical measurements. 5. Plasma production. 6. Space plasms simulations. This facility has been managed under Laboratory Space Plasma Comittee since 1969 and used by scientists in cooperative programs with universities and institutes all over country. A list of publications is attached. (author)

  8. Stability of Streamer Chamber

    Science.gov (United States)

    Wada, Toshiaki; Ogawa, Masato; Takahashi, Kaoru; Sugiyama, Tsunetoshi; Kobayashi, Shigeharu; Kohno, Hirobumi

    1982-08-01

    The quality of tracks obtained from a streamer chamber is studied through the measurement of the streamer brightness. The stability of streamer tracks depends on the value of the high voltage applied and its shape. By using a single conical-type spark gap as the pulse shaper, stable brightness of the streamer tracks is attained. The data on the streamer brightness are compared with the result by Bulos et al. and it is found that the brightness is more strongly affected by field parameters than in their result.

  9. Stability of streamer chamber

    International Nuclear Information System (INIS)

    Wada, Toshiaki; Ogawa, Masato; Takahashi, Kaoru; Sugiyama, Tsunetoshi; Kobayashi, Shigeharu; Kohno, Hirobumi.

    1982-01-01

    The quality of tracks obtained from a streamer chamber is studied through the measurement of the streamer brightness. The stability of streamer tracks depends on the value of the high voltage applied and its shape. By using a single conical-type spark gap as the pulse shaper, stable brightness of the streamer tracks is attained. The data on the streamer brightness are compared with the result by Bulos et al. and it is found that the brightness is more strongly affected by field parameters than in their result. (author)

  10. Council Chamber exhibition

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    To complete the revamp of CERN’s Council Chamber, a new exhibition is being installed just in time for the June Council meetings.   Panels will showcase highlights of CERN’s history, using some of the content prepared for the exhibitions marking 50 years of the PS, which were displayed in the main building last November. The previous photo exhibition in the Council Chamber stopped at the 1970s. To avoid the new panels becoming quickly out of date, photos are grouped together around specific infrastructures, rather than following a classic time-line. “We have put the focus on the accelerators – the world-class facilities that CERN has been offering researchers over the years, from the well-known large colliders to the lesser-known smaller facilities,” says Emma Sanders, who worked on the content. The new exhibition will be featured in a future issue of the Bulletin with photos and an interview with Fabienne Marcastel, designer of the exhibit...

  11. Time projection chamber

    International Nuclear Information System (INIS)

    Kamae, Tsuneyoshi

    1984-01-01

    A time projection chamber (TPC) was developed at Lawrence Berkeley Laboratory to compensate the shortcoming of drift chambers. The characteristics of the TPC are the improvement of the distortion of the trace of particles in long drift, the improvement of particle identification by taking out the analog signal proportional to the number of electrons, and the improvement of the method to analyze the three-dimensional analog signal. Two large TPC's are designed and manufactured in Japan. The details of these TPC's are explained in this paper. The results of test experiment are as follows. The accuracy of the measurement of particle position was about 100 micrometer in the r-theta plane and about 340 micrometer in the Z-direction. The accuracy of the measurement of ionization loss (dE/dx) was less than 4.0 percent. The reconstruction of quark pair production can be made. At present, the identification of K-mesons in jet phenomena is possible, and the cross-sections of inclusive processes are easily obtained. (Kato, T.)

  12. Factors related to the incidence of anterior disc displacement without reduction and bony changes of the temporomandibular joint in patients with anterior open bite.

    Science.gov (United States)

    Ooi, Kazuhiro; Yura, Shinya; Inoue, Nobuo; Totsuka, Yasunori

    2014-12-01

    We aimed to investigate factors related to the prevalence of anterior disc displacement without reduction (ADDwoR) and bony changes of the condylar head (bony changes) in the temporomandibular joints (TMJs) of patients with anterior open bite. Subjects are comprised of 36 preoperative patients (72 joints) with skeletal anterior open bite without facial asymmetry who had undergone orthognathic surgery at the Hokkaido University Hospital; magnetic resonance imaging of the TMJ and cephalometric analysis were performed before treatment. Logistic regression analysis was performed to clarify relationships among age, overbite, overjet, ANB angle, sella to nasion (SN) to mandibular plane angle (SN-MP angle), SN to ramus plane angle (GZN angle), gonial angle, and incidence of ADDwoR or bony changes in patients with anterior open bite. Fifteen patients had bilateral ADDwoR, and five patients had unilateral ADDwoR; 17 patients had bilateral bony changes, and five patients had unilateral bony changes. SN-MP angle was greater in 20 patients with ADDwoR than that in 16 patients without ADDwoR (p < 0.05). GZN angle was greater in the 20 patients showing bony changes than that in the 16 patients without bony changes (p < 0.05). In terms of dentofacial morphology, SN-MP angle appears to be associated with the incidence of ADDwoR, and GZN angle appears to be associated with bony changes in the TMJ.

  13. Multiple Coronary Chamber Microfistulas or Persistent Thebesian Vessels?

    Directory of Open Access Journals (Sweden)

    Cernica Daniel

    2017-09-01

    Full Text Available Coronary fistulas are rare, not gender-specific congenital conditions, consisting of communications between the coronary arteries and either another coronary vessel or a cardiac chamber. In contrast to large fistulas, small fistulas, named “minimae cordis veneae” or the Thebesius venous system, are draining into heart chambers and form a vascular network in the cardiac lumen. In this article, we present the case of a 72-year-old female with a significant history of cardiovascular disease, admitted to our clinic because of rest dyspnea, fatigue, and minimal chest pain. The 12-lead electrocardiogram showed a trifascicular block (a second-degree atrioventricular block Mobitz II, associated with a right bundle branch block and left anterior fascicle block and negative T waves in DII, DIII, aVF, V4–V6 leads. An invasive coronary angiography was performed, which revealed no significant atherosclerotic lesions. However, a persistent capillary blush was present at the apex site of the left ventricular chamber, draining from the distal segments of both the anterior descending coronary artery and the posterior interventricular coronary artery. The intramural vascular network generating a left ventricle angiogram image of this kind was suggestive for persistent Thebesian vessels connecting the two coronaries with the left ventricular chamber.

  14. Michigan ATLAS MDT Chamber Mass Production

    CERN Document Server

    Diehl, E; Levin, D; McKee, S; Neal, H; Schick, H; Tarle, G; Thun, R; Weaverdyck, C; Xu, Q; Zhao, Z; Zhou, B

    2001-01-01

    This paper describes the ATLAS MDT precision muon chamber construction at the University of Michigan. The chamber assembly facilities, the jigging set up, alignment procedures, and other measurements necessary for chamber assembly are described. The chamber quality assurance monitoring procedures and data for the first year mass production are presented. The chamber gas system assembly facilities, and the chamber leak test procedure together with data also reported. The chamber production database, which monitors chamber production, is also discussed.

  15. Swept source optical coherence tomography measurement of the iris-trabecular contact (ITC) index: a new parameter for angle closure.

    Science.gov (United States)

    Ho, Sue-Wei; Baskaran, Mani; Zheng, Ce; Tun, Tin A; Perera, Shamira A; Narayanaswamy, Arun K; Friedman, David S; Aung, Tin

    2013-04-01

    To evaluate the inter- and intra-observer agreement of measurement of the iris-trabecular contact (ITC) index, a measure of the degree of angle closure, using swept source optical coherence tomography (SSOCT, CASIA SS-1000, Tomey Corporation, Nagoya, Japan). One randomly selected eye of 60 subjects was imaged under dark room conditions. The SSOCT 3-dimensional angle scan simultaneously obtains 128 radial scans of the anterior chamber for the entire circumference of the angle. Post-imaging analysis estimated the ITC index using in-built software. For intra-observer agreement for image grading, one examiner performed the grading twice in a masked fashion and random order after a 1-week interval. A second examiner graded images to assess inter-observer agreement for image grading. For intra-observer agreement for image acquisition, a single operator imaged patients twice. For inter-observer agreement for image acquisition, a single observer graded two sets of images acquired by two different operators on the same patient. Bland-Altman plots and 95 % limits of agreement (LOA) were reported. Study subjects were predominantly Chinese (54/60, 90 %) and female (42/60, 70 %), with a mean age of 65.5 years. The median ITC index for eyes with open angles (31/60) and closed angles was 20 % (95 % confidence interval [CI] - 13.6, 27.8) and 49 % (95%CI - 35.5, 69.2) respectively. The mean difference (95 % LOA) for intra-observer agreement for image grading and image acquisition were -0.8 % (-8.2, 6.5) and 0.6 % (-10.9, 9.7); corresponding inter- observer agreement were 0.1 % (-10, 10.1) and -0.3 % (-11.1, 10.5) respectively. The inter- and intra-observer agreement of the ITC index, as a measure of extent of angle closure using SSOCT, was good.

  16. Congenital anterior urethral diverticulum

    International Nuclear Information System (INIS)

    Jung, Hyun Sub; Chung, Young Sun; Suh, Chee Jang; Won, Jong Jin

    1985-01-01

    Two cases of congenital anterior urethral diverticular which have occurred in a 4 year old and one month old boy are presented. Etiology, diagnostic procedures, and its clinical results are briefly reviewed

  17. Anterior knee pain

    Science.gov (United States)

    ... thighbone where the kneecap normally rests is too shallow. You have flat feet. Anterior knee pain is ... the principles of the Health on the Net Foundation (www.hon.ch). The information provided herein should ...

  18. Mush Column Magma Chambers

    Science.gov (United States)

    Marsh, B. D.

    2002-12-01

    Magma chambers are a necessary concept in understanding the chemical and physical evolution of magma. The concept may well be similar to a transfer function in circuit or time series analysis. It does what needs to be done to transform source magma into eruptible magma. In gravity and geodetic interpretations the causative body is (usually of necessity) geometrically simple and of limited vertical extent; it is clearly difficult to `see' through the uppermost manifestation of the concentrated magma. The presence of plutons in the upper crust has reinforced the view that magma chambers are large pots of magma, but as in the physical representation of a transfer function, actual magma chambers are clearly distinct from virtual magma chambers. Two key features to understanding magmatic systems are that they are vertically integrated over large distances (e.g., 30-100 km), and that all local magmatic processes are controlled by solidification fronts. Heat transfer considerations show that any viable volcanic system must be supported by a vertically extensive plumbing system. Field and geophysical studies point to a common theme of an interconnected stack of sill-like structures extending to great depth. This is a magmatic Mush Column. The large-scale (10s of km) structure resembles the vertical structure inferred at large volcanic centers like Hawaii (e.g., Ryan et al.), and the fine scale (10s to 100s of m) structure is exemplified by ophiolites and deeply eroded sill complexes like the Ferrar dolerites of the McMurdo Dry Valleys, Antarctica. The local length scales of the sill reservoirs and interconnecting conduits produce a rich spectrum of crystallization environments with distinct solidification time scales. Extensive horizontal and vertical mushy walls provide conditions conducive to specific processes of differentiation from solidification front instability to sidewall porous flow and wall rock slumping. The size, strength, and time series of eruptive behavior

  19. Diogene pictorial drift chamber

    International Nuclear Information System (INIS)

    Gosset, J.

    1984-01-01

    A pictorial drift chamber, called DIOGENE, has been installed at Saturne in order to study central collisions of high energy heavy ions. It has been adapted from the JADE internal detector, with two major differences to be taken into account. First, the center-of-mass of these collisions is not identical to the laboratory reference frame. Second, the energy loss and the momentum ranges of the particles to be detected are different from the ones in JADE. It was also tried to keep the cost as small as possible, hence the choice of minimum size and minimum number of sensitive wires. Moreover the wire planes are shifted from the beam axis: this trick helps very much to quickly reject the bad tracks caused by the ambiguity of measuring drift distances (positive or negative) through times (always positive)

  20. Thin wall vacuum reaction chamber for neutron measurement

    International Nuclear Information System (INIS)

    Banerjee, K.; Meena, J.K.; Bhattacharya, Sumantra; Bhattacharya, S.; Bhattacharya, C.; Roy, P.; Saha, A.K.; Ghosh, T.K.; Kundu, S.; Rana, T.K.; Mukherjee, G.; Pandey, R.; Sahoo, J.K.; Saha Mondal, R.; Yadav, R.C.; Chatterjee, S.

    2013-01-01

    A thin wall (3 mm) stainless steel vacuum reaction chamber has been designed, fabricated and installed in the K500 superconducting beam hall at VECC for the in-beam experiment. The chamber is spherical in shape, with inner diameter 1010 mm, having three independent sections. The middle segment is fixed to the beam line, whereas the two hemispherical sections are removable type with the help of hydraulic trolleys. This specific design facilitates almost 360 degree access of the chamber for setting up an experiment. The typical vacuum ∼ 4 x 10 -7 mbar is achieved by two 550 lit/sec air cooled turbo molecular pumps backed by two 35 m 3 /hr scroll pumps in ∼ 8 hours. PLC based control system has been developed for the operation of pumps. 12 rings are fabricated to mount detectors, each having 440 mm radius and separated by 30° from each other in polar angle. These rings are supported inside the chamber by two flanges placed along the beam line. These rings are properly calibrated in polar and azimuthal angles with respect to the centre of the chamber. (author)

  1. BILATERAL ACUTE ANGLE CLOSURE GLAUCOMA AND MYOPIA INDUCED BY LOW DOSAGE TOPIRAMATE

    Directory of Open Access Journals (Sweden)

    Busra S. Arica

    2014-09-01

    Full Text Available Introduction: Topiramate, a sulfamate-substituted monosaccharide, has been shown to be effective in the treatment of epilepsy and migraine prophylaxis. However, acute secondary angle closure glaucoma and myopia has been shown to develop, especially during the first two weeks of treatment, in a small subset of patients. Case presentation: In the current case report, a 23 year old female patient developed acute myopia and angle closure glaucoma after one week topiramate treatment (25 mg/day for prophylaxis of migraine without aura. The patient was found to have significant conjunctival hyperemia, shallow anterior chamber, and bulging iris in both eyes. Grade 1 acute angle was detected in both eyes during gonioscopic examination. There was no pupillary block and intraocular pressure was 40 mmHg in both eyes. Refraction values were measured at -7.00 and -8.00 in the right and left eye, respectively. The patient and #8217;s visual acuity was at 0.1 to 0.2. Topiramate treatment was promptly discontinued, topical antiglaucomatous treatment was initiated, and laser peripheral iridotomy was performed on each eye. Intraocular pressure has declined to normal limits, refractive values were zero in both eyes and patient and #8217;s visual acuity has restored at follow-up period at 10 days after treatment. Conclusion: Side effects associated with topiramate treatments are known to disappear without long-term damage when the discontinuation of therapy and effective interventions are started early. Therefore, patients and their physicians should be alert for symptoms associated with acute secondary angle closure glaucoma and myopia; especially in the first weeks of topiramate treatment also with low dosage. [J Contemp Med 2014; 4(3.000: 168-171

  2. Galvanic vestibular stimulation may improve anterior bending posture in Parkinson's disease.

    Science.gov (United States)

    Okada, Yohei; Kita, Yorihiro; Nakamura, Junji; Kataoka, Hiroshi; Kiriyama, Takao; Ueno, Satoshi; Hiyamizu, Makoto; Morioka, Shu; Shomoto, Koji

    2015-05-06

    This study investigated the effects of binaural monopolar galvanic vestibular stimulation (GVS), which likely stimulates the bilateral vestibular system, on the anterior bending angle in patients with Parkinson's disease (PD) with anterior bending posture in a single-blind, randomized sham-controlled crossover trial. The seven PD patients completed two types of stimulation (binaural monopolar GVS and sham stimulation) applied in a random order 1 week apart. We measured each patient's anterior bending angles while he or she stood with eyes open and eyes closed before/after the stimulations. The anterior bending angles in both the eyes-open and the eyes-closed conditions were significantly reduced after the GVS. The amount of change in the eyes-closed condition post-GVS was significantly larger than that by sham stimulation. The amount of change in anterior bending angles in the GVS condition was not significantly correlated with Unified Parkinson's Disease Rating Scale motor score, disease duration, the duration of the postural deformities, and the anterior bending angles before the GVS. Binaural monopolar GVS might improve anterior bending posture in PD patients, irrespective of the duration and the severity of disease and postural deformities. Binaural monopolar GVS might be a novel treatment strategy to improve anterior bending posture in PD.

  3. Peltier-based cloud chamber

    Science.gov (United States)

    Nar, Sevda Yeliz; Cakir, Altan

    2018-02-01

    Particles produced by nuclear decay, cosmic radiation and reactions can be identified through various methods. One of these methods that has been effective in the last century is the cloud chamber. The chamber makes visible cosmic particles that we are exposed to radiation per second. Diffusion cloud chamber is a kind of cloud chamber that is cooled by dry ice. This traditional model has some application difficulties. In this work, Peltier-based cloud chamber cooled by thermoelectric modules is studied. The new model provided uniformly cooled base of the chamber, moreover, it has longer lifetime than the traditional chamber in terms of observation time. This gain has reduced the costs which spent each time for cosmic particle observation. The chamber is an easy-to-use system according to traditional diffusion cloud chamber. The new model is portable, easier to make, and can be used in the nuclear physics experiments. In addition, it would be very useful to observe Muons which are the direct evidence for Lorentz contraction and time expansion predicted by Einsteins special relativity principle.

  4. Recombination chambers for BNCT dosimetry

    International Nuclear Information System (INIS)

    Tulik, Piotr

    2006-01-01

    Parallel plate recombination ionization chambers are known as the detectors which can be used for determination of gamma and high-LET dose components and for characterization of radiation quality of mixed radiation fields. Specially designed chambers can operate correctly even at dose rates of therapeutic beams. In this work the investigations were extended to a set of cylindrical chambers including a TE chamber and three graphite chambers filled with different gases - CO 2 , N 2 and 10 BF 3 , in order to determine the thermal neutrons, 14 N capture, gamma, and fast neutron dose components. The separation of the dose components is based on differences of the shape of the saturation curve, in dependence on LET spectrum of the investigated radiation. The measurements using all the chambers and a parallel plate recombination chamber were performed in a reactor beam of NRI Rez (Czech Republic). The gamma component was determined with accuracy of about 5%, while the variations of its value could be monitored with accuracy of about 0.5%. Relative changes of the beam components could be detected with accuracy of about 5% using the parallel plate chamber. The use of the chambers filled with different gases considerably improved the resolution of the method. (author)

  5. Bilateral spontaneous dislocation of posterior chamber intraocular lens in a patient with gyrate atrophy

    Directory of Open Access Journals (Sweden)

    Michael Kinori

    2012-01-01

    Full Text Available We report a patient with gyrate atrophy, a rare metabolic disease, who had bilateral late spontaneous posterior dislocation of in-the-bag posterior chamber intraocular lens (PCIOL. He underwent pars plana vitrectomy, PCIOL retrieval and anterior chamber intraocular lens implantation in both eyes. This report may imply that patients with gyrate atrophy are at risk for spontaneous dislocation of intraocular lenses.

  6. MRI appearances of the anterior fibulocalcaneus muscle: a rare anterior compartment muscle

    Energy Technology Data Exchange (ETDEWEB)

    Upadhyay, Bhavin [Basildon and Thurrock University Hospitals NHS Foundation Trust, Imaging Department, Essex (United Kingdom); Amiras, Dimitri [Imperial College Health Care NHS Trust, Imaging Department, London (United Kingdom)

    2015-05-01

    MRI of a 62-year-old female presenting with ankle pain demonstrated an accessory muscle within the anterior compartment of the lower leg. The muscle originated from the fibula and anterior crural septum. The tendon passed anterior to the lateral malleolus and inserted at the critical angle of Gissane on the calcaneus. This muscle was initially described in the anatomic literature by Lambert and Atsas in 2010. To our knowledge, this is the first time the MRI appearances of this muscle has been described in the radiological literature. Awareness of the fibulocalcaneal muscle is important as it may represent a cause of ankle pain. In addition, the tendon could potentially be harvested for use in reconstructive procedures. (orig.)

  7. Contact Angle Goniometer

    Data.gov (United States)

    Federal Laboratory Consortium — Description:The FTA32 goniometer provides video-based contact angle and surface tension measurement. Contact angles are measured by fitting a mathematical expression...

  8. Radon detection in conical diffusion chambers: Monte Carlo calculations and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rickards, J.; Golzarri, J. I.; Espinosa, G., E-mail: espinosa@fisica.unam.mx [Instituto de Física, Universidad Nacional Autónoma de México Circuito de la Investigación Científica, Ciudad Universitaria México, D.F. 04520, México (Mexico); Vázquez-López, C. [Departamento de Física, Centro de Investigación y de Estudios Avanzados del IPN Ave. IPN 2508, Col. San Pedro Zacatenco, México 07360, DF, México (Mexico)

    2015-07-23

    The operation of radon detection diffusion chambers of truncated conical shape was studied using Monte Carlo calculations. The efficiency was studied for alpha particles generated randomly in the volume of the chamber, and progeny generated randomly on the interior surface, which reach track detectors placed in different positions within the chamber. Incidence angular distributions, incidence energy spectra and path length distributions are calculated. Cases studied include different positions of the detector within the chamber, varying atmospheric pressure, and introducing a cutoff incidence angle and energy.

  9. Under-air staining of the anterior capsule using Trypan blue with a 30 G needle

    Directory of Open Access Journals (Sweden)

    Giammaria D

    2013-01-01

    Full Text Available Daniele Giammaria,1 Michele Giannotti,2 Angelo Scopelliti,1 Giacomo Pellegrini,1 Bruno Giannotti11Azienda Ospedaliera Ospedali Riuniti Marche Nord, Fano, Italy; 2Catholic University of Rome, Rome, ItalyAbstract: The original technique of staining the anterior capsule of the lens with Trypan blue involves the injection of an air bubble in the anterior chamber. A drawback of this technique is the possible instability of the anterior chamber caused by the sudden exit of air when the dye is injected with the cannula through the side-port incision. Other staining techniques that use viscoelastic substances to increase the stability of the anterior chamber and to dose the injected dye have been described. The authors present an under-air staining technique of the anterior capsule using one drop of Trypan blue injected with a 30 G needle through the peripheral cornea. This procedure prevents the air bubble from escaping the anterior chamber and allows fast and selective staining of the capsule.Keywords: Trypan blue, staining technique, dye, cataract surgery, capsulorhexis

  10. National Ignition Facility Target Chamber

    International Nuclear Information System (INIS)

    Wavrik, R W; Cox, J R; Fleming, P J

    2000-01-01

    On June 11, 1999 the Department of Energy dedicated the single largest piece of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The ten (10) meter diameter aluminum target high vacuum chamber will serve as the working end of the largest laser in the world. The output of 192 laser beams will converge at the precise center of the chamber. The laser beams will enter the chamber in two by two arrays to illuminate 10 millimeter long gold cylinders called hohlraums enclosing 2 millimeter capsule containing deuterium, tritium and isotopes of hydrogen. The two isotopes will fuse, thereby creating temperatures and pressures resembling those found only inside stars and in detonated nuclear weapons, but on a minute scale. The NIF Project will serve as an essential facility to insure safety and reliability of our nation's nuclear arsenal as well as demonstrating inertial fusion's contribution to creating electrical power. The paper will discuss the requirements that had to be addressed during the design, fabrication and testing of the target chamber. A team from Sandia National Laboratories (SNL) and LLNL with input from industry performed the configuration and basic design of the target chamber. The method of fabrication and construction of the aluminum target chamber was devised by Pitt-Des Moines, Inc. (PDM). PDM also participated in the design of the chamber in areas such as the Target Chamber Realignment and Adjustment System, which would allow realignment of the sphere laser beams in the event of earth settlement or movement from a seismic event. During the fabrication of the target chamber the sphericity tolerances had to be addressed for the individual plates. Procedures were developed for forming, edge preparation and welding of individual plates. Construction plans were developed to allow the field construction of the target chamber to occur parallel to other NIF construction activities. This was

  11. The CLEO III drift chamber

    CERN Document Server

    Peterson, D; Briere, R A; Chen, G; Cronin-Hennessy, D; Csorna, S; Dickson, M; Dombrowski, S V; Ecklund, K M; Lyon, A; Marka, S; Meyer, T O; Patterson, J R; Sadoff, A; Thies, P; Thorndike, E H; Urner, D

    2002-01-01

    The CLEO group at the Cornell Electron Storage Ring has constructed and commissioned a new central drift chamber. With 9796 cells arranged in 47 layers ranging in radius from 13.2 to 79 cm, the new drift chamber has a smaller outer radius and fewer wires than the drift chamber it replaces, but allows the CLEO tracking system to have improved momentum resolution. Reduced scattering material in the chamber gas and in the inner skin separating the drift chamber from the silicon vertex detector provides a reduction of the multiple scattering component of the momentum resolution and an extension of the usable measurement length into the silicon. Momentum resolution is further improved through quality control in wire positioning and symmetry of the electric fields in the drift cells which have provided a reduction in the spatial resolution to 88 mu m (averaged over the full drift range).

  12. Temporalis and masseter muscle activity in patients with anterior open bite and craniomandibular disorders

    DEFF Research Database (Denmark)

    Bakke, Merete; Michler, L

    1991-01-01

    values, particularly in subjects with muscular affection, but maximal activity increased significantly when biting on the splint. Maximal voluntary contraction was positively correlated to molar contact and negatively to anterior face height, mandibular inclination, vertical jaw relation and gonial angle...

  13. Posterior maxillary (PM) plane and anterior cranial architecture in primates.

    Science.gov (United States)

    McCarthy, R C; Lieberman, D E

    2001-11-01

    This study tests several hypotheses of integration between the cranial base and face in primates. After reviewing the definition and anatomical basis for the posterior maxillary (PM) plane, which demarcates the back of the midface at its junction with the sphenoid, we demonstrate how the PM plane can be identified accurately on radiographs, and confirm that it maintains a 90 degrees angle relative to the Neutral Horizontal Axis of the orbits in all primates. In addition, we use the PM plane to test Dabelow's (1929) hypothesis that the orbits and anterior cranial base are more highly integrated in anthropoids than in strepsirrhines, and we test the hypothesis that the midline anterior cranial base (planum sphenoideum) and anterior cranial floor (planum sphenoideum plus cribriform plate) in primates are highly correlated with each other relative to the PM plane. The mean angle between the anterior cranial base and the PM plane does not differ significantly from 90 degrees in anthropoids, but differs significantly in strepsirrhines. The anterior cranial base and anterior cranial floor, however, correlate well with each other relative to the PM plane in both suborders of primates, independent of orbital orientation and configuration. The PM plane, anterior cranial base, and anterior cranial floor, therefore, form an integrated structural complex, a "facial block," whose orientation relative to the posterior cranial base influences craniofacial shape among anthropoids in which orbital orientation influences the orientation of the anterior cranial base. One such effect is that increases in cranial base flexion shorten the antero-posterior length of the nasopharynx. Copyright 2001 Wiley-Liss, Inc.

  14. Quantification of static magnetic field effects on radiotherapy ionization chambers

    Science.gov (United States)

    Agnew, J.; O'Grady, F.; Young, R.; Duane, S.; Budgell, G. J.

    2017-03-01

    Integrated magnetic resonance (MR) imaging and radiotherapy (RT) delivery machines are currently being developed, with some already in clinical use. It is anticipated that the strong magnetic field used in some MR-RT designs will have a significant impact on routine measurements of dose in the MR-linac performed using ionization chambers, which provide traceability back to a primary standard definition of dose. In particular, the presence of small air gaps around ionization chambers may introduce unacceptably high uncertainty into these measurements. In this study, we investigate and quantify the variation attributable to air gaps for several routinely-used cylindrical ionization chambers in a magnetic field, as well as the effect of the magnetic field alone on the response of the chambers. The measurements were performed in a Co-60 beam, while the ionization chambers were positioned in custom-made Perspex phantoms between the poles of an electromagnet, which was capable of generating magnetic fields of up to 2 T field strength, although measurements were focused around 1.5 T. When an asymmetric air gap was rotated at cardinal angles around the ionization chambers investigated here, variation of up to 8.5  ±  0.2 percentage points (PTW 31006 chamber) was observed in an applied magnetic field of 1.5 T. The minimum peak-to-peak variation was 1.1  ±  0.1% (Exradin A1SL). When the same experiment was performed with a well-defined air gap of known position using the PTW 30013 chamber, a variation of 3.8  ±  0.2% was observed. When water was added to the phantom cavity to eliminate all air gaps, the variation for the PTW 30013 was reduced to 0.2  ±  0.01%.

  15. The high momentum spectrometer drift chambers

    Science.gov (United States)

    Abbott, D.; Baker, O. K.; Beaufait, J.; Bennett, C.; Bryant, E.; Carlini, R.; Kross, B.; McCauley, A.; Naing, W.; Shin, T.; Vulcan, W.

    1992-12-01

    The High Momentum Spectrometer in Hall C will use planar drift chambers for charged particle track reconstruction. The chambers are constructed using well understood technology and a conventional gas mixture. Two (plus one spare) drift chambers will be constructed for this spectrometers. Each chamber will contain 6 planes of readout channels. This paper describes the chamber design and gas handling system used.

  16. Behaviour of large cylindrical drift chambers in a superconducting solenoid

    International Nuclear Information System (INIS)

    Boer, W. de; Fues, W.; Grindhammer, G.; Kotthaus, R.; Lierl, H.; Moss, L.

    1980-04-01

    We describe the construction and behaviour of a set of cylindrical drift chambers operating inside a superconducting solenoid with a central magnetic field of 1.3 T. The chambers are part of the 4 π detector CELLO at the e + e - storage ring PETRA in Hamburg. The chambers were designed without field shaping to keep them as simple as possible. In order to parametrize accurately the nonlinear space-time relation, we used a computer simulation of the drift process in inhomogenous electric and magnetic fields. With such a parametrization we achieved a resolution of 210 μm, averaged over the whole drift cell and angles of incidence up to 30 0 . (orig.)

  17. anterior hyaloidal fibrovascular proliferation

    African Journals Online (AJOL)

    Okonkwo

    It most commonly occurs after phakic vitrectomy and scleral buckling for diabetic traction retinal detachment. It usually manifests with haemorrhage into the vitreous cavity or anterior hyaloid 3 to 12 weeks after vitrectomy and is the result of fibrovascular proliferation from the peripheral retina extending toward the equator of ...

  18. Micro plate fission chamber development

    International Nuclear Information System (INIS)

    Wang Mei; Wen Zhongwei; Lin Jufang; Jiang Li; Liu Rong; Wang Dalun

    2014-01-01

    To conduct the measurement of neutron flux and the fission rate distribution at several position in assemblies, the micro plate fission chamber was designed and fabricated. Since the requirement of smaller volume and less structure material was taken into consideration, it is convinient, commercial and practical to use fission chamber to measure neutron flux in specific condition. In this paper, the structure of fission chamber and process of fabrication were introduced and performance test result was presented. The detection efficiency is 91.7%. (authors)

  19. Neutron detection via bubble chambers.

    Science.gov (United States)

    Jordan, D V; Ely, J H; Peurrung, A J; Bond, L J; Collar, J I; Flake, M; Knopf, M A; Pitts, W K; Shaver, M; Sonnenschein, A; Smart, J E; Todd, L C

    2005-01-01

    Research investigating the application of pressure-cycled bubble chambers to fast neutron detection is described. Experiments with a Halon-filled chamber showed clear sensitivity to an AmBe neutron source and insensitivity to a (137)Cs gamma source. Bubble formation was documented using high-speed photography, and a ceramic piezo-electric transducer element registered the acoustic signature of bubble formation. In a second set of experiments, the bubble nucleation response of a Freon-134a chamber to an AmBe neutron source was documented with high-speed photography.

  20. Neutron detection via bubble chambers

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, D.V. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States)]. E-mail: david.jordan@pnl.gov; Ely, J.H. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States); Peurrung, A.J. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States); Bond, L.J. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States); Collar, J.I. [Department of Physics and Enrico Fermi Institute, University of Chicago, 5640 S. Ellis Ave., LASR 214, Chicago, IL 60637 (United States); Flake, M. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States); Knopf, M.A. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States); Pitts, W.K. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States); Shaver, M. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States); Sonnenschein, A. [Department of Physics and Enrico Fermi Institute, University of Chicago, 5640 S. Ellis Ave., LASR 214, Chicago, IL 60637 (United States); Smart, J.E. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States); Todd, L.C. [Pacific Northwest National Laboratory, MS P8-20, P.O. Box 999, Richland, WA 99352 (United States)

    2005-12-01

    Research investigating the application of pressure-cycled bubble chambers to fast neutron detection is described. Experiments with a Halon-filled chamber showed clear sensitivity to an AmBe neutron source and insensitivity to a {sup 137}Cs gamma source. Bubble formation was documented using high-speed photography, and a ceramic piezo-electric transducer element registered the acoustic signature of bubble formation. In a second set of experiments, the bubble nucleation response of a Freon-134a chamber to an AmBe neutron source was documented with high-speed photography.

  1. Pelletron general purpose scattering chamber

    International Nuclear Information System (INIS)

    Chatterjee, A.; Kailas, S.; Kerekette, S.S.; Navin, A.; Kumar, Suresh

    1993-01-01

    A medium sized stainless steel scattering chamber has been constructed for nuclear scattering and reaction experiments at the 14UD pelletron accelerator facility. It has been so designed that several types of detectors, varying from small sized silicon surface barrier detectors to medium sized gas detectors and NaI detectors can be conveniently positioned inside the chamber for detection of charged particles. The chamber has been planned to perform the following types of experiments : angular distributions of elastically scattered particles, fission fragments and other charged particles, angular correlations for charged particles e.g. protons, alphas and fission fragments. (author). 2 figs

  2. Toxic Anterior Segment Syndrome following a Triple Descemet’s Stripping Automated Endothelial Keratoplasty Procedure

    Directory of Open Access Journals (Sweden)

    Nir Sorkin

    2012-11-01

    Full Text Available Purpose: To present a unique case of a 58-year-old female with toxic anterior segment syndrome (TASS, following a triple procedure: Descemet’s stripping automated endothelial keratoplasty (DSAEK, phacoemulsification and posterior chamber intraocular lens implantation. Methods: The patient was treated with topical dexamethasone sodium phosphate 0.1% and topical atropine sulfate 1%. Due to a slow improvement in her clinical status, oral prednisone 1 mg/kg/day was added. Results: The anterior chamber reaction improved gradually, with tapering down of topical and oral treatment, until a complete resolution of the anterior chamber reaction was observed. Conclusions: Taking into account the estimated volume of DSAEK triple procedures performed worldwide, we would expect an annual incidence of several TASS cases, following triple DSAEK procedures. However, we were unable to find any such previous reports in the literature. This fact raises questions regarding the cause of reduced TASS incidence following triple DSAEK procedures.

  3. Rupture pressure of the posterior lamella obtained during big-bubble deep anterior lamellar keratoplasty.

    Science.gov (United States)

    McKee, Hamish D; Barua, Ankur; Brahma, Arun K; Jhanji, Vishal; Carley, Fiona M

    2012-11-01

    To investigate the pressure required to rupture the posterior lamella obtained during the presumed Descemet membrane-baring big-bubble technique of deep anterior lamellar keratoplasty (DALK). DALK using the big-bubble technique was carried out on donor corneoscleral discs mounted on an artificial anterior chamber. Once the anterior lamella was removed, the chamber was connected to a mercury manometer. The pressure inside the chamber was increased until rupture occurred or the manometer reached its measurement limit. The deep lamella ruptured at 252 mm Hg in one cornea, at 270 mm Hg in another, and had not ruptured at 300 mm Hg (upper limit of the manometer) in the remaining 18 donor corneas. The posterior lamella of big-bubble DALK probably confers significant structural integrity on the globe.

  4. The HARP resistive plate chambers: Characteristics and physics performance

    International Nuclear Information System (INIS)

    Ammosov, V.; Boyko, I.; Chelkov, G.; Dedovitch, D.; Dumps, R.; Dydak, F.; Elagin, A.; Gapienko, V.; Gostkin, M.; Guskov, A.; Kroumchtein, Z.; Koreshev, V.; Linssen, L.; Nefedov, Yu.; Nikolaev, K.; Semak, A.; Sviridov, Yu.; Usenko, E.; Wotschack, J.; Zaets, V.; Zhemchugov, A.

    2007-01-01

    The HARP Resistive Plate Chamber (RPC) system was designed for time-of-flight measurement in the large-angle acceptance region of the HARP spectrometer. It comprised 46 four-gap glass RPCs covering an area of ∼8m 2 . The design of the RPCs, their operation, intrinsic properties, and system performance are described. The intrinsic time resolution of the RPCs is better than 130ps leading to a system time resolution of ∼175ps

  5. Mega-bicone vacuum chamber for ISR intersections

    CERN Multimedia

    CERN PhotoLab

    1975-01-01

    The cylindrical central part covered the collision region allowing secondary particles emitted at large angle to escape thanks to its very thin wall.The two conical parts are terminated by "transparent" thin windows for letting out forward emitted secondary particles. Vacuum chambers of this shape were made in their thin parts out of 0.3 mm stainless steel or 0.28 mm titanium alloy sheet. See also 7609219, 7609221, 7507132X.

  6. Development, construction and test of the planar forward drift chambers of the ZEUS inner detector and analyses of chamber properties

    International Nuclear Information System (INIS)

    Kramarczyk, S.

    1993-08-01

    The three planar drift chambers FTD1-3 are part of the inner tracking system of the ZEUS detector at the ep facility HERA, DESY. Together with 2x2 transition radiation modules they form the Forward Detector which covers the range of forward (proton) angles. Development, construction and tests of the drift chambers are described, emphasizing design features and details of the manufacture. Two compensation methods were tested to annihilate the cross talk which emerges from the influence of one signal wire on the others in the same drift cell. A prototyp system of the final digital readout electronics was used together with a test cell. The single wire resolution was studied with optimized drift time algorithms. For the first time it was possible to measure the influence of the track angle on the single wire resolution of the FTDs. (orig.)

  7. The multigap resistive plate chamber

    Energy Technology Data Exchange (ETDEWEB)

    Zeballos, E. Cerron [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Crotty, I. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Hatzifotiadou, D. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Valverde, J. Lamas [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Univ. Louis Pasteur, Strasbourg (France); Neupane, S. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Williams, M. C. S. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Zichichi, A. [Univ. of Bologna, Bologna (Italy)

    2015-02-03

    The paper describes the multigap resistive plate chamber (RPC). This is a variant of the wide gap RPC. However it has much improved time resolution, while keeping all the other advantages of the wide gap RPC design.

  8. Light diffusing fiber optic chamber

    Science.gov (United States)

    Maitland, Duncan J.

    2002-01-01

    A light diffusion system for transmitting light to a target area. The light is transmitted in a direction from a proximal end to a distal end by an optical fiber. A diffusing chamber is operatively connected to the optical fiber for transmitting the light from the proximal end to the distal end and transmitting said light to said target area. A plug is operatively connected to the diffusing chamber for increasing the light that is transmitted to the target area.

  9. Advances on fission chamber modelling

    International Nuclear Information System (INIS)

    Filliatre, Philippe; Jammes, Christian; Geslot, Benoit; Veenhof, Rob

    2013-06-01

    In-vessel, online neutron flux measurements are routinely performed in mock-up and material testing reactors by fission chambers. Those measurements have a wide range of applications, including characterization of experimental conditions, reactor monitoring and safety. Depending on the application, detectors may experience a wide range of constraints, of several magnitudes, in term of neutron flux, gamma-ray flux, temperature. Hence, designing a specific fission chamber and measuring chain for a given application is a demanding task. It can be achieved by a combination of experimental feedback and simulating tools, the latter being based on a comprehensive understanding of the underlying physics. A computation route that simulates fission chambers, named CHESTER, is presented. The retrieved quantities of interest are the neutron-induced charge spectrum, the electronic and ionic pulses, the mean current and variance, the power spectrum. It relies on the GARFIELD suite, originally developed for drift chambers, and makes use of the MAGBOLTZ code to assess the drift parameters of electrons within the filling gas, and the SRIM code to evaluate the stopping range of fission products. The effect of the gamma flux is also estimated. Computations made with several fission chambers exemplify the possibilities of the route. A good qualitative agreement is obtained when comparing the results with the experimental data available to date. In a near future, a comprehensive experimental programme will be undertaken to qualify the route using the known neutron sources, mock-up reactors and wide choice of fission chambers, with a stress on the predictiveness of the Campbelling mode. Depending on the results, a refinement of the modelling and an effort on the accuracy of input data are also to be considered. CHESTER will then make it possible to predict the overall sensitivity of a chamber, and to optimize the design for a given application. Another benefit will be to increase the

  10. Proton beam monitor chamber calibration

    International Nuclear Information System (INIS)

    Gomà, C; Meer, D; Safai, S; Lorentini, S

    2014-01-01

    The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences—of the order of 3%—were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth—i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers—rather than cylindrical chambers—for the reference dosimetry of pseudo-monoenergetic proton beams. (paper)

  11. BEBC Big European Bubble Chamber

    CERN Multimedia

    CERN PhotoLab

    1974-01-01

    A view of the dismantling of the magnet of BEBC, the 3.7 m European Bubble Chamber : iron magnetic shielding ; lower and upper parts of the vacuum enclosure of the magnet; turbo-molecular vacuum pumps for the "fish-eye" windows; the two superconducting coils; a handling platform; the two cryostats suspended from the bar of the travelling crane which has a 170 ton carrying capacity. The chamber proper, not dismantled, is inside the shielding.

  12. Anterior cruciate ligament repair - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100230.htm Anterior cruciate ligament repair - Series—Normal anatomy To use the sharing ... to slide 5 out of 5 Overview The anterior cruciate ligament (ACL) is a ligament in the center of ...

  13. Multidisciplinary management of anterior diastemata

    DEFF Research Database (Denmark)

    Furuse, Adilson Yoshio; Herkrath, Fernando José; Franco, Eduardo Jacomino

    2007-01-01

    Anterior diastemata may compromise the harmony of a patient's smile. Consideration of etiologic factors, previous gingival conditioning, and individual treatment planning are essential in the proper management of anterior diastemata. An integrated orthodontic-restorative approach may enhance...

  14. Implantation of scleral fixated sutured posterior chamber lenses: a retrospective analysis of 119 cases.

    Science.gov (United States)

    Krause, Lothar; Bechrakis, Nikolaos E; Heimann, Heinrich; Salditt, Stefan; Foerster, Michael H

    2009-08-01

    The implantation of scleral fixated sutured posterior chamber lenses enables lens implantation in the absence of adequate lens capsule support. Anterior chamber lenses and their side effects can also be avoided, particularly in cases of unilateral aphakia and contact lens incompatibility. This study is a retrospective analysis of 119 scleral fixated sutured posterior chamber lenses implanted in 115 patients. Seventy-nine cases of damaged zonula or damaged lens capsule and 17 cases of corneal decompensation secondary to anterior chamber lenses were the main indications for the suture fixation. The mean follow-up was 23 months (6-83 months). In 50% of all cases, improved visual acuity was achieved. Twenty-four percent of patients showed unchanged visual acuity, while 26% had poorer vision postoperatively, mainly because of corneal decompensation following anterior chamber lens explantation. The main postoperative complication was transient rise of intraocular pressure, occurring in 44% of the cases. In most cases improved or comparable postoperative visual acuity was achieved. The main complication observed was postoperative glaucoma, especially in patients with pre-existing glaucoma.

  15. Optimal Entry Point and Trajectory for Anterior C1 Lateral Mass Screw.

    Science.gov (United States)

    Hu, Yong; Dong, Wei-Xin; Spiker, William Ryan; Yuan, Zhen-Shan; Sun, Xiao-Yang; Zhang, Jiao; Xie, Hui; Albert, Todd J

    2017-06-01

    A radiographic analysis of the anatomy of the C1 lateral mass using computed tomography (CT) scans and Mimics software. To define the anatomy of the C1 lateral mass and make recommendations for optimal entry point and trajectory for anterior C1 lateral mass screws. Although various posterior insertion angles and entry points for screw insertion have been proposed for posterior C1 lateral mass screws, no large series have been performed to assess the ideal entry point and optimal trajectory for anterior C1 lateral mass screw placement. The C1 lateral mass was evaluated using CT scans and a 3-dimensional imaging application (Mimics software). Measuring the space available for the anterior C1 lateral mass screw (SAS) at different camber angles from 0 to 30 degrees (5-degree intervals) was performed to identify the ideal camber angle of insertion. Measuring the range of sagittal angles was performed to calculate the ideal sagittal angle. Other measurements involving the height of the C1 lateral mass were also made. The optimal screw entry point was found to be located on the anterior surface of the atlas 12.88 mm (±1.10 mm) lateral to the center of the anterior tubercle. This optimal entry point was found to be 6.81 mm (±0.59 mm) superior to the anterior edge of the atlas inferior articulating process. The mean ideal camber angle was 20.92 degrees laterally and the mean ideal sagittal angle was 5.80 degrees downward. These measurements define the optimal entry point and trajectory for anterior C1 lateral mass screws and facilitate anterior C1 lateral mass screw placement. A thorough understanding of the local anatomy may decrease the risk of injury to the spinal cord, vertebral artery, and internal carotid artery. Delineating the anatomy in each case with preoperative 3D CT evaluation is recommended.

  16. Intraoperative Fluoroscopy Improves Component Position During Anterior Hip Arthroplasty.

    Science.gov (United States)

    Jennings, John D; Iorio, Justin; Kleiner, Matthew T; Gaughan, John P; Star, Andrew M

    2015-11-01

    The goal of this retrospective review was to determine whether fluoroscopic guidance improves acetabular cup abduction and anteversion alignment during anterior total hip arthroplasty. The authors retrospectively reviewed 199 patients (fluoroscopy group, 98; nonfluoroscopy group, 101) who underwent anterior total hip arthroplasty at a single center with and without C-arm fluoroscopy guidance. Included in the study were patients of any age who underwent primary anterior approach total hip arthroplasty performed by a single surgeon, with 6-month postoperative anteroposterior pelvis radiographs. Acetabular cup abduction and anteversion angles were measured and compared between groups. Mean acetabular cup abduction and anteversion angles were 43.4° (range, 26.0°-57.4°) and 23.1° (range, 17°-28°), respectively, in the fluoroscopy group. Mean abduction and anteversion angles were 45.9° (range, 29.7°-61.3°) and 23.1° (range, 17°-28°), respectively, after anterior total hip arthroplasty without the use of C-arm guidance (nonfluoroscopy group). The use of fluoroscopy was associated with a statistically significant difference in cup abduction (P=.002) but no statistically significant difference in anteversion angles. In the fluoroscopy group, 80% of implants were within the combined safe zone compared with 63% in the nonfluoroscopy group. A significantly higher percentage of both acetabular cup abduction angles and combined anteversion and abduction angles were in the safe zone in the fluoroscopy group. Fluoroscopy is not required for proper anteversion placement of acetabular components, but it may increase ideal safe zone placement of components. Copyright 2015, SLACK Incorporated.

  17. Reading Angles in Maps

    Science.gov (United States)

    Izard, Véronique; O'Donnell, Evan; Spelke, Elizabeth S.

    2014-01-01

    Preschool children can navigate by simple geometric maps of the environment, but the nature of the geometric relations they use in map reading remains unclear. Here, children were tested specifically on their sensitivity to angle. Forty-eight children (age 47:15-53:30 months) were presented with fragments of geometric maps, in which angle sections…

  18. Capsular phimosis with complete occlusion of the anterior capsular opening after intact continuous curvilinear capsulorrhexis

    International Nuclear Information System (INIS)

    AlKharashi, Soliman A

    2009-01-01

    Shrinkage and whitening of the anterior capsule opening - capsular contraction syndrome - is a well-known complication after continuous curvilinear capsulorrhexis. A 72-year-old women underwent continuous curvilinear capsulorrhexis, phacoemulsification, and implantation of posterior chamber intraocular lens with polymethylmethacrylate haptics. Four months postoperatively, the patient reported deterioration in visual acuity that was resulted due to complete occlusion of anterior capsular opening by fibrotic tissue. The fibrous membrane was excised surgically in capsulorrhexis fashion. (author)

  19. Optimal reconstruction angles

    International Nuclear Information System (INIS)

    Cook, G.O. Jr.; Knight, L.

    1979-07-01

    The question of optimal projection angles has recently become of interest in the field of reconstruction from projections. Here, studies are concentrated on the n x n pixel space, where literative algorithms such as ART and direct matrix techniques due to Katz are considered. The best angles are determined in a Gauss--Markov statistical sense as well as with respect to a function-theoretical error bound. The possibility of making photon intensity a function of angle is also examined. Finally, the best angles to use in an ART-like algorithm are studied. A certain set of unequally spaced angles was found to be preferred in several contexts. 15 figures, 6 tables

  20. Anterior Urethral Valves

    Directory of Open Access Journals (Sweden)

    Vidyadhar P. Mali

    2006-07-01

    Full Text Available We studied the clinical presentation and management of four patients with anterior urethral valves; a rare cause of urethral obstruction in male children. One patient presented antenatally with oligohydramnios, bilateral hydronephrosis and bladder thickening suggestive of an infravesical obstruction. Two other patients presented postnatally at 1 and 2 years of age, respectively, with poor stream of urine since birth. The fourth patient presented at 9 years with frequency and dysuria. Diagnosis was established on either micturating cystourethrogram (MCU (in 2 or on cystoscopy (in 2. All patients had cystoscopic ablation of the valves. One patient developed a postablation stricture that was resected with an end-to-end urethroplasty. He had an associated bilateral vesicoureteric junction (VUJ obstruction for which a bilateral ureteric reimplantation was done at the same time. On long-term follow-up, all patients demonstrated a good stream of urine. The renal function is normal. Patients are continent and free of urinary infections. Anterior urethral valves are rare obstructive lesions in male children. The degree of obstruction is variable, and so they may present with mild micturition difficulty or severe obstruction with hydroureteronephrosis and renal impairment. Hence, it is important to evaluate the anterior urethra in any male child with suspected infravesical obstruction. The diagnosis is established by MCU or cystoscopy and the treatment is always surgical, either a transurethral ablation or an open resection. The long-term prognosis is good.

  1. Directional muon jet chamber for a muon collider (Groovy Chamber)

    International Nuclear Information System (INIS)

    Atac, M.

    1996-10-01

    A directional jet drift chamber with PAD readout is proposed here which can select vertex originated muons within a given time window and eliminate those muons which primarily originate upstream, using only a PAD readout. Drift time provides the Z-coordinate, and the center of gravity of charge distribution provides the r-ψ coordinates. Directionality at the trigger level is obtained by the timing measurement from the PAD hits within a given time window. Because of the long drift time between the bunch crossings, a muon collider enables one to choose a drift distance in the drift chamber as long as 50 cm. This is an important factor in reducing cost of drift chambers which have to cover relatively large areas

  2. The anterior talofibular and calcaneofibular ligaments: an anatomic study.

    Science.gov (United States)

    Yıldız, Selda; Yalcın, Bulent

    2013-08-01

    Inversion injuries of the ankle are the most common sport injuries. Extreme inversion of the ankle affects frequently lateral ankle ligaments, especially the anterior talofibular and calcaneofibular ligaments. The aim of this study is to investigate the ligaments in detail to contribute to accurate evaluation of radiological investigations and more precise surgical interventions by clarifying the anatomic structure of the ligaments by considering their functional importance. In the study, length between the attachment points and width at the midpoint of the anterior talofibular and calcaneofibular ligaments, length and width of the bands of anterior talofibular ligament, and connecting ligaments extending from the talus to calcaneus exchanging from the both ligaments were measured on the 46 ankles. In addition, angles between these ligaments and between longitudinal axis of the fibula and both ligaments were measured. Relationship between determined variables on the right and left sides was statistically analyzed. In diagnosis and treatment methods, the clinical importance of the anatomy of the lateral collateral ligaments of the ankle, especially the anterior talofibular and calcaneofibular ligaments, was frequently reported in the literature. Angular measurements benefit in determination of the ligament injury. Therefore, knowledge about normal anatomic angles between each other and angles between longitudinal axis of the fibula and both ligaments was certainly important for the correct diagnosis. Nowadays, surgical reconstructions of the ligaments are frequently used. During the surgical invention, length and width of the ligaments are necessary to determine quantity of ligament loss. Nonetheless, knowledge of ligament attachments contributes to more accurate reconstructions.

  3. Morphometric changes of corneal endothelial cells following intracameral air for micro perforation of the Descemet Membrane during big-bubble deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Ashbala Khattak

    2016-04-01

    Conclusion: The presence of air inside the anterior chamber for a short term may not cause further endothelial cell loss and can be safely performed to prevent postoperative Descemet Membrane detachment in case of micro perforations.

  4. Plasma chemistry in wire chambers

    International Nuclear Information System (INIS)

    Wise, J.

    1990-05-01

    The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an 55 Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed

  5. Neutron Detection via Bubble Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, David V.; Ely, James H.; Peurrung, Anthony J.; Bond, Leonard J.; Collar, J. I.; Flake, Matthew; Knopf, Michael A.; Pitts, W. K.; Shaver, Mark W.; Sonnenschein, Andrew; Smart, John E.; Todd, Lindsay C.

    2005-10-06

    The results of a Pacific Northwest National Laboratory (PNNL) exploratory research project investigating the feasibility of fast neutron detection using a suitably prepared and operated, pressure-cycled bubble chamber are described. The research was conducted along two parallel paths. Experiments with a slow pressure-release Halon chamber at the Enrico Fermi Institute at the University of Chicago showed clear bubble nucleation sensitivity to an AmBe neutron source and insensitivity to the 662 keV gammas from a 137Cs source. Bubble formation was documented via high-speed (1000 frames/sec) photography, and the acoustic signature of bubble formation was detected using a piezo-electric transducer element mounted on the base of the chamber. The chamber’s neutron sensitivity as a function of working fluid temperature was mapped out. The second research path consisted of the design, fabrication, and testing of a fast pressure-release Freon-134a chamber at PNNL. The project concluded with successful demonstrations of the PNNL chamber’s AmBe neutron source sensitivity and 137Cs gamma insensitivity. The source response tests of the PNNL chamber were documented with high-speed photography.

  6. Photoelectric angle converter

    Science.gov (United States)

    Podzharenko, Volodymyr A.; Kulakov, Pavlo I.

    2001-06-01

    The photo-electric angle transmitter of rotation is offered, at which the output voltage is linear function of entering magnitude. In a transmitter the linear phototransducer is used on the basis of pair photo diode -- operating amplifier, which output voltage is linear function of the area of an illuminated photosensitive stratum, and modulator of a light stream of the special shape, which ensures a linear dependence of this area from an angle of rotation. The transmitter has good frequent properties and can be used for dynamic measurements of an angular velocity and angle of rotation, in systems of exact drives and systems of autocontrol.

  7. Perawatan Ortodontik Gigitan Terbuka Anterior

    Directory of Open Access Journals (Sweden)

    Yuniar Zen

    2014-06-01

    Full Text Available Perawatan gigitan terbuka anterior telah lama dianggap sebagai tantangan bagi ortodontis. Prevalensi gigitan terbuka anterior antara 3,5% hingga 11% terdapat pada berbagai usia dan kelompok etnis, serta ada sekitar 17% pasien ortodonti memiliki gigitan terbuka. Stabilitas hasil perawatan gigitan terbuka anterior sangat sulit, karena adanya kombinasi diskrepansi anteroposterior dengan gigitan terbuka skeletal sehingga dibutuhkan tingkat keterampilan diagnosis dan klinis yang tinggi. Etiologi gigitan terbuka anterior sangat kompleks karena dapat melibatkan skeletal, dental, dan faktor-faktor habitual. Eliminasi faktor etiologi merupakan hal yang penting dalam perawatan gigitan terbuka anterior. Berbagai cara perawatan untuk koreksi gigitan terbuka anterior diantaranya bedah ortognatik dan perawatan ortodontik kamuflase, seperti high-pull headgear, chincup, bite blocks, alatfungsional, pencabutan gigi, multi-loop edgewise archwires dan mini implan. Stabilitas hasil perawatan adalah kriteria yang paling penting dalam menentukan cara perawatan gigitan terbuka anterior. Orthodontic Treatment of Anterior Open Bite. An anterior open bite therapy has long been considered a challenge to orthodontist. The prevalence of anterior openbite range from 3,5 % to 11% among various age and ethnic groups and it has been shown that approximately 17% of orthodontic patients have open bite. Stability of treatment result of anterior open bite with well-maintained results is difficult, because the combination of anteroposteriorly discrepancy with skeletal open bite requires the highest degree of diagnostic and clinical skill. The etiology is complex, potentially involving skeletal, dental and habitual factors. The importance of an anterior open bite therapy is to eliminate the cause of the open bite. Various treatment modalities for the correction of an anterior open bite have been proposed, orthognatic surgery and orthodontic camouflage treatment such as high

  8. The CLAS drift chamber system

    CERN Document Server

    Mestayer, M D; Asavapibhop, B; Barbosa, F J; Bonneau, P; Christo, S B; Dodge, G E; Dooling, T; Duncan, W S; Dytman, S A; Feuerbach, R; Gilfoyle, G P; Gyurjyan, V; Hicks, K H; Hicks, R S; Hyde-Wright, C E; Jacobs, G; Klein, A; Klein, F J; Kossov, M; Kuhn, S E; Magahiz, R A; Major, R W; Martin, C; McGuckin, T; McNabb, J; Miskimen, R A; Müller, J A; Niczyporuk, B B; O'Meara, J E; Qin, L M; Raue, B A; Robb, J; Roudot, F; Schumacher, R A; Tedeschi, D J; Thompson, R A; Tilles, D; Tuzel, W; Vansyoc, K; Vineyard, M F; Weinstein, L B; Wilkin, G R; Yegneswaran, A; Yun, J

    2000-01-01

    Experimental Hall B at Jefferson Laboratory houses the CEBAF Large Acceptance Spectrometer, the magnetic field of which is produced by a superconducting toroid. The six coils of this toroid divide the detector azimuthally into six sectors, each of which contains three large multi-layer drift chambers for tracking charged particles produced from a fixed target on the toroidal axis. Within the 18 drift chambers are a total of 35,148 individually instrumented hexagonal drift cells. The novel geometry of these chambers provides for good tracking resolution and efficiency, along with large acceptance. The design and construction challenges posed by these large-scale detectors are described, and detailed results are presented from in-beam measurements.

  9. "Flat-Fish" Vacuum Chamber

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    The picture shows a "Flat-Fish" vacuum chamber being prepared in the ISR workshop for testing prior to installation in the Split Field Magnet (SFM) at intersection I4. The two shells of each part were hydroformed from 0.15 mm thick inconel 718 sheet (with end parts in inconel 600 for easier manual welding to the arms) and welded toghether with two strips which were attached by means of thin stainless steel sheets to the Split Field Magnet poles in order to take the vertical component of the atmospheric pressure force. This was the thinnest vacuum chamber ever made for the ISR. Inconel material was chosen for its high elastic modulus and strenght at chamber bake-out temperature. In this picture the thin sheets transferring the vertical component of the atmosferic pressure force are attached to a support frame for testing. See also 7712182, 7712179.

  10. Holography in small bubble chambers

    International Nuclear Information System (INIS)

    Lecoq, P.

    1984-01-01

    This chapter reports on an experiment to determine the total charm cross section at different incident momenta using the small, heavy liquid bubble chamber HOBC. Holography in liquid hydrogen is also tested using the holographic lexan bubble chamber HOLEBC with the aim of preparing a future holographic experiment in hydrogen. The high intensity tests show that more than 100 incident tracks per hologram do not cause a dramatic effect on the picture quality. Hydrogen is more favorable than freon as the bubble growth is much slower in hydrogen. An advantage of holography is to have the maximum resolution in the full volume of the bubble chamber, which allows a gain in sensitivity by a factor of 10 compared to classical optics as 100 tracks per hologram look reasonable. Holograms are not more difficult to analyze than classical optics high-resolution pictures. The results show that holography is a very powerful technique which can be used in very high resolution particle physics experiments

  11. Anterior knee pain

    Energy Technology Data Exchange (ETDEWEB)

    LLopis, Eva [Hospital de la Ribera, Alzira, Valencia (Spain) and Carretera de Corbera km 1, 46600 Alzira Valencia (Spain)]. E-mail: ellopis@hospital-ribera.com; Padron, Mario [Clinica Cemtro, Ventisquero de la Condesa no. 42, 28035 Madrid (Spain)]. E-mail: mario.padron@clinicacemtro.com

    2007-04-15

    Anterior knee pain is a common complain in all ages athletes. It may be caused by a large variety of injuries. There is a continuum of diagnoses and most of the disorders are closely related. Repeated minor trauma and overuse play an important role for the development of lesions in Hoffa's pad, extensor mechanism, lateral and medial restrain structures or cartilage surface, however usually an increase or change of activity is referred. Although the direct relation of cartilage lesions, especially chondral, and pain is a subject of debate these lesions may be responsible of early osteoarthrosis and can determine athlete's prognosis. The anatomy and biomechanics of patellofemoral joint is complex and symptoms are often unspecific. Transient patellar dislocation has MR distinct features that provide evidence of prior dislocation and rules our complication. However, anterior knee pain more often is related to overuse and repeated minor trauma. Patella and quadriceps tendon have been also implicated in anterior knee pain, as well as lateral or medial restraint structures and Hoffa's pad. US and MR are excellent tools for the diagnosis of superficial tendons, the advantage of MR is that permits to rule out other sources of intraarticular derangements. Due to the complex anatomy and biomechanic of patellofemoral joint maltracking is not fully understood; plain films and CT allow the study of malalignment, new CT and MR kinematic studies have promising results but further studies are needed. Our purpose here is to describe how imaging techniques can be helpful in precisely defining the origin of the patient's complaint and thus improve understanding and management of these injuries.

  12. Complications and Management of Deep Anterior Lamellar Keratoplasty

    Directory of Open Access Journals (Sweden)

    Banu Torun Acar

    2014-10-01

    Full Text Available Objectives: To report the intraoperative and postoperative follow-up complications and management of these in deep anterior lamellar keratoplasty (DALK surgery. Materials and Methods: Two hundred eighty-four eyes of 252 patients followed up in our cornea clinic who underwent DALK using Anwar’s big-bubble technique with healthy Descemet’s membrane and endothelium were included in this study. Intraoperative and postoperative complications as well as the management and treatment of these complications were evaluated. Results: Big bubble was created in 220 (77.5% eyes of 284 eyes, and lamellar dissection was performed in 64 (22.5% eyes. Perforation occurred during trephination in 4 eyes, and the procedure was accomplished by penetrating keratoplasty (PK. Intraoperative microperforation occurred in 44 eyes. Perforation enlarged in 4 eyes and PK was performed. Operation was continued in 40 eyes with air injection into the anterior chamber. In postopertive follow-up period, double anterior chamber (DAC occurred in 32 of 40 eyes. DAC spontaneously regressed in 8 eyes, and air was given into the anterior chamber with a second surgical intervention in 24 eyes. DAC improved in 20 eyes. Four eyes underwent PK. Fungal keratitis evolved at the interface in one eye, because of no healing during the follow-up period, this eye underwent PK under antifungal therapy. Eyes with interface haze and Descemet’s membrane folds were followed. Conclusion: DALK is a difficult technique with a steep learning curve. In addition to the complications seen in PK, specific complications can occur in lamellar surgery. (Turk J Ophthalmol 2014; 44: 337-40

  13. Angles in hyperbolic lattices

    DEFF Research Database (Denmark)

    Risager, Morten S.; Södergren, Carl Anders

    2017-01-01

    It is well known that the angles in a lattice acting on hyperbolic n -space become equidistributed. In this paper we determine a formula for the pair correlation density for angles in such hyperbolic lattices. Using this formula we determine, among other things, the asymptotic behavior of the den......It is well known that the angles in a lattice acting on hyperbolic n -space become equidistributed. In this paper we determine a formula for the pair correlation density for angles in such hyperbolic lattices. Using this formula we determine, among other things, the asymptotic behavior...... of the density function in both the small and large variable limits. This extends earlier results by Boca, Pasol, Popa and Zaharescu and Kelmer and Kontorovich in dimension 2 to general dimension n . Our proofs use the decay of matrix coefficients together with a number of careful estimates, and lead...

  14. Evaluating anterior knee pain.

    Science.gov (United States)

    Hong, Engene; Kraft, Michael C

    2014-07-01

    Musculoskeletal complaints account for about 20% to 30% of all primary care office visits; of these visits, discomfort in the knee, shoulder, and back are the most prevalent musculoskeletal symptoms. Having pain or dysfunction in the front part of the knee is a common presentation and reason for a patient to see a health care provider. There are a number of pathophysiological etiologies to anterior knee pain. This article describes some of the common and less common causes, and includes sections on diagnosis and treatment for each condition as well as key points. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. The anterior cingulate cortex

    Directory of Open Access Journals (Sweden)

    Pavlović D.M.

    2009-01-01

    Full Text Available The anterior cingulate cortex (ACC has a role in attention, analysis of sensory information, error recognition, problem solving, detection of novelty, behavior, emotions, social relations, cognitive control, and regulation of visceral functions. This area is active whenever the individual feels some emotions, solves a problem, or analyzes the pros and cons of an action (if it is a right decision. Analogous areas are also found in higher mammals, especially whales, and they contain spindle neurons that enable complex social interactions. Disturbance of ACC activity is found in dementias, schizophrenia, depression, the obsessive-compulsive syndrome, and other neuropsychiatric diseases.

  16. MRI anatomy of anteriorly displaced anus: what obstructs defecation?

    International Nuclear Information System (INIS)

    AbouZeid, Amr Abdelhamid; Mohammad, Shaimaa Abdelsattar; Khairy, Khaled Talaat

    2014-01-01

    Anteriorly displaced anus is an anomaly that is debated with regard to its nomenclature, diagnosis and management. To describe MRI anatomy of the anal canal in children with anteriorly displaced anus and its impact on the process of defecation. We prospectively examined ten children (7 girls, 3 boys; age range 7 months to 8 years, mean 3 years) with anteriorly displaced anus between August 2009 and April 2012. Noncontrast MRI examinations were performed on a 1.5-T magnet. T1- and T2-weighted turbo spin-echo images were acquired in axial, sagittal and coronal planes of the pelvis. The anorectal angle and the relative hiatal distance were measured in mid-sagittal images, and compared with those of a control group using the Mann-Whitney test. In children with anteriorly displaced anus, no anatomical abnormality was depicted at the level of the proximal anal canal. However, the distal anal canal was displaced anteriorly, running out its external muscle cuff, which remained un-displaced at the usual site of the anus. This changes the orientation of the central axis of the anal canal by passing across instead of along the fibers of the longitudinal muscle coat. Children with anteriorly displaced anus had a more obtuse anorectal angle (mean 112.1 ), which was significantly greater than that of the control group (mean 86.2 ). MRI is a valuable tool in studying the anatomy of the anal canal in children with anteriorly displaced anus. The abnormal orientation of the longitudinal muscle across the anal canal can explain the obstructed defecation in these children. Based on this study, it might be of interest to use MRI in studying equivocal cases and children with unexplained constipation. (orig.)

  17. MRI anatomy of anteriorly displaced anus: what obstructs defecation?

    Energy Technology Data Exchange (ETDEWEB)

    AbouZeid, Amr Abdelhamid [Ain-Shams University, Department of Pediatric Surgery, Cairo (Egypt); Mohammad, Shaimaa Abdelsattar; Khairy, Khaled Talaat [Ain-Shams University, Department of Radiodiagnosis, Cairo (Egypt)

    2014-07-15

    Anteriorly displaced anus is an anomaly that is debated with regard to its nomenclature, diagnosis and management. To describe MRI anatomy of the anal canal in children with anteriorly displaced anus and its impact on the process of defecation. We prospectively examined ten children (7 girls, 3 boys; age range 7 months to 8 years, mean 3 years) with anteriorly displaced anus between August 2009 and April 2012. Noncontrast MRI examinations were performed on a 1.5-T magnet. T1- and T2-weighted turbo spin-echo images were acquired in axial, sagittal and coronal planes of the pelvis. The anorectal angle and the relative hiatal distance were measured in mid-sagittal images, and compared with those of a control group using the Mann-Whitney test. In children with anteriorly displaced anus, no anatomical abnormality was depicted at the level of the proximal anal canal. However, the distal anal canal was displaced anteriorly, running out its external muscle cuff, which remained un-displaced at the usual site of the anus. This changes the orientation of the central axis of the anal canal by passing across instead of along the fibers of the longitudinal muscle coat. Children with anteriorly displaced anus had a more obtuse anorectal angle (mean 112.1 ), which was significantly greater than that of the control group (mean 86.2 ). MRI is a valuable tool in studying the anatomy of the anal canal in children with anteriorly displaced anus. The abnormal orientation of the longitudinal muscle across the anal canal can explain the obstructed defecation in these children. Based on this study, it might be of interest to use MRI in studying equivocal cases and children with unexplained constipation. (orig.)

  18. Ionization chambers for LET determination

    DEFF Research Database (Denmark)

    Kaiser, Franz-Joachim; Bassler, Niels; Tölli, Heikki

    2010-01-01

    resolution and high sensitivity are necessary. For exact dosimetry which is done using ionization chambers (ICs), the recombination taking place in the IC has to be known. Up to now, recombination is corrected phenomenologically and more practical approaches are currently used. Nevertheless, Jaff´e's theory...... of columnar recombination was designed to model the detector efficiency of an ionization chamber. Here, we have shown that despite the approximations and simplification made, the theory is correct for the LETs typically found in clinical radiotherapy employing particles from protons to carbon ions...

  19. Laboratory Course on Drift Chambers

    International Nuclear Information System (INIS)

    Garcia-Ferreira, Ix-B.; Garcia-Herrera, J.; Villasenor, L.

    2006-01-01

    Drift chambers play an important role in particle physics experiments as tracking detectors. We started this laboratory course with a brief review of the theoretical background and then moved on to the the experimental setup which consisted of a single-sided, single-cell drift chamber. We also used a plastic scintillator paddle, standard P-10 gas mixture (90% Ar, 10% CH4) and a collimated 90Sr source. During the laboratory session the students performend measurements of the following quantities: a) drift velocities and their variations as function of the drift field; b) gas gains and c) diffusion of electrons as they drifted in the gas

  20. [Zebrafish-a new animal models of anterior segment embryonic development and diseases basic research].

    Science.gov (United States)

    Hao, Yong-na; Wei, Rui-hua; Zhao, Shao-zhen

    2012-01-01

    In recent years, zebrafish has become ideal animal models of human disease with its unique characteristics, such as small body, fecundity, fast development and growth, embryo transparency, and so on. Furthermore, the structure and gene of zebrafish eye are highly conservative with human eye, which make ophthalmologists to pay close attention to zebrafish. This review focus on the studies and applications on zebrafish embryonic development of anterior segment, including the morphogenesis of cornea, lens and anterior chamber, and diseases of anterior segment (corneal diseases, cataract, glaucoma).

  1. Sexual dimorphism of the internal mandibular chamber in Fayum Pliohyracidae (Mammalia)

    Science.gov (United States)

    de Blieux, D.D.; Baumrind, M.R.; Simons, E.L.; Chatrath, P.S.; Meyer, G.E.; Attia, Y.S.

    2006-01-01

    An internal mandibular fenestra and chamber are found in many fossil hyracoids. The internal mandibular fenestra is located on the lingual surface of the mandibular corpus and opens into a chamber within the mandible. The mandibular chamber is maximally developed in late Eocene Thyrohyrax meyeri and early Oligocene Thyrohyrax domorictus from the Fayum Province of Egypt. The function of this chamber is unknown as it is not found in extant hyraxes, nor is it known to occur in any other mammal. In Thyrohyrax, this feature appears to be sexually dimorphic because it is confined to roughly one half of the specimens that otherwise cannot be separated by dental characteristics or measurements. It has been suggested that the chamber is found in females based on the presumed distribution of this character in other fossil hyracoids. Fossils from Fayum Quarry L-41, preserving the sexually dimorphic anterior dentition, show that, in Thyrohyrax meyeri and Thyrohyrax domorictus, the internal mandibular chamber is found in males. In Thyrohyrax litholagus, an internal mandibular fenestra and inflated mandibular chamber occurs in males whereas females show the variable presence of an internal mandibular fossa or fenestra but lack an expanded chamber. Other genera show differing patterns of sexual variation in which some Fayum hyracoids have an internal mandibular fenestra in both sexes but with the greatest development of the mandibular chamber occurring in males. We review functions proposed for the internal mandibular chamber and suggest that it housed a laryngeal air sac that may have had a vocal function by acting as a resonating chamber. ?? 2006 by the Society of Vertebrate Paleontology.

  2. Compact multiwire proportional chambers and electronics for the crystal ball detector

    International Nuclear Information System (INIS)

    Gaiser, J.E.; Liberman, A.D.; Rolfe, J.

    1978-01-01

    A double gap of cylindrical proportional chambers has been designed and built for use with a large solid angle, modular NaI(Tl) array (The Crystal Ball). The chambers are constructed of three coaxial foam-epoxy shells, covered with an aluminum-mylar laminate. One of the high voltage cathodes in each chamber has been photo-etched to produce a pattern of stripes and precise position measurements of tracks passing transverse to the chamber axis are found by pulse height analyzing the shaped and amplified induced strip signals. Performance of the chamber using both the strip signals and the sense wire readout is presented. The design of both the signal handling electronics and the digital portions of the systems is discussed

  3. The laser system for calibration and monotoring of the Opal jet chamber

    International Nuclear Information System (INIS)

    Biebel, O.; Boden, B.; Bug, S.; Eyring, A.; Fischer, H.M.; Geich-Gimbel, C.; Gross, S.; Knop, G.; Levegruen, S.; Maringer, G.; Mauer, E.; Maur, U.; Nellen, B.; Neumann, H.; Rollnik, A.; Schreiber, S.; Simon, A.; Thiebes, J.; Wolf, B.; Wuensch, B.; Boerner, H.; Breuker, H.; Hagemann, J.; Hauschild, M.; Heuer, R.D.; Karner, K.; Linser, G.; Runolfsson, O.; Seidl, W.; Voillat, D.; Wicht, P.; Schmitt, H. von der; Wagner, A.

    1992-01-01

    In this report we describe the construction and performance of the laser system which was used in Summer 1989 for the initial calibration of the OPAL jet chamber after installation on the LEP beam axis and which has served as a monitoring tool since then. Two Nd:YAG lasers are used to generate 48 high precision double beams which enter the chamber at fixed positions. The main features of the roughly 450 optical components are described and the beam alignment procedures are explained. Results are given for jet chamber calibration constants such as drift velocity, Lorentz angle, and residual sagittas. (orig.)

  4. Some aspects of the applications of wire chambers in high energy physics experiments at large accelerators

    International Nuclear Information System (INIS)

    Turala, M.

    1982-01-01

    An application of proportional and drift chambers in four large spectrometers at the accelerators of IHEP Serpukhov and CERN Geneva is described. An operation of wire chambers at high intensities and high multiplicities of particles is discussed. The results of investigations of their efficiencies, spatial resolution (for one and two-dimensional readout) and long term stability are presented. Problems of preselection of a given class of events are discussed. The systems for preselection of defined multiplicities or a scattering angle of particles, in which proportional chambers have been used, are described and the results of their application in the real experiments are presented. (author)

  5. Gun barrel view of the anterior pelvic ring for percutaneous anterior column or superior pubic ramus screw placement.

    Science.gov (United States)

    Quercetti, Nicholas; Horne, Brandon; DiPaolo, Zac; Prayson, Michael J

    2017-07-01

    Traditionally, operative fixation of pelvic and acetabular injuries involves complex approaches and significant complications. Accelerated rehabilitation, decreased soft tissue stripping and decreased wound complications are several benefits driving a recent interest in percutaneous fixation. We describe a new fluoroscopic view to guide the placement of screws within the anterior pelvic ring. Twenty retrograde anterior pelvic ring screws were percutaneously placed in ten cadaveric specimens. Arranging a standard C-arm in a position similar to obtaining a lateral hip image, with angles of 54° ± 2° beam to body, 75° ± 5° of reverse cantilever and 14° ± 6° of outlet, a gun barrel view of the anterior pelvic ring is identified. Fluoroscopic images were taken, and the hemipelvi were harvested to examine the dimensions of the anterior pelvic ring and inspected for any cortical or articular perforation. The minimum cranial-to-caudal distance in the anterior pelvic ring was 9 mm (range 6.5-12 mm), and the minimum anterior-to-posterior dimension was 9 mm (range 5-15 mm). All but 2 screws were completely confined within the osseous corridors. Identifiable on final fluoroscopic evaluation, one screw perforated the psoas groove and a second perforated the acetabular dome. Overall, 90 % of our screws were accurately and safely placed, upon the first attempt, within the anterior pelvic ring using the described gun barrel view. Employing either open reduction, or following a closed or percutaneous reduction, the anterior pelvic ring gun barrel view can reproducibly guide safe placement of anterior pelvic ring screw fixation. IV.

  6. Histological findings of failed gold micro shunts in primary open-angle glaucoma.

    Science.gov (United States)

    Agnifili, Luca; Costagliola, Ciro; Figus, Michele; Iezzi, Giovanna; Piattelli, Adriano; Carpineto, Paolo; Mastropasqua, Rodolfo; Nardi, Marco; Mastropasqua, Leonardo

    2012-01-01

    To describe the histological features of failed gold micro shunts (GMS) in unsuccessful implantations for refractory primary open-angle glaucoma (POAG). This was an interventional case series study. Five eyes of five glaucomatous patients with unsuccessful GMS implantation underwent shunt removal. Each device was sectioned into three portions: proximal or anterior chamber (AC) portion, middle or scleral portion and distal or suprachoroidal (SC) portion. The histological analysis was performed throughout the whole extent of the shunt, describing both the inner spaces and the outer surface. At the moment of removal all devices were correctly located into the SC space and in AC, with the exception of a case presenting corneal endothelial contact. The mean intra-ocular pressure before GMS removal was 30.4 ± 5.3 mmHg, and the mean time of GMS removal after implantation was 6.8 ± 2.5 months. No significant histological differences were documented among the five analyzed devices. The main feature was the presence of a thick connective capsule-like reaction surrounding both the proximal and distal ends and invading the posterior and anterior grid holes, whereas a more loosely arranged connective tissue was observed within the inner channels. Signs of surface fibrosis of the middle-scleral portion and inflammatory cell infiltration of the device were not documented in any of the cases. Failed GMS implantations presented connective tissue filling all the inner spaces and creating a thick fibrotic capsule surrounding the ends of the device. This modification isolated the GMS from the AC and SC space, impeding aqueous flows throughout the shunt.

  7. Landmarks for Identifying the Suprascapular Foramen Anteriorly: Application to Anterior Neurotization and Decompressive Procedures.

    Science.gov (United States)

    Manouvakhova, Olga V; Macchi, Veronica; Fries, Fabian N; Loukas, Marios; De Caro, Raffaele; Oskouian, Rod J; Spinner, Robert J; Tubbs, R Shane

    2018-02-01

    Additional landmarks for identifying the suprascapular nerve at its entrance into the suprascapular foramen from an anterior approach would be useful to the surgeon. To identify landmarks for the identification of this hidden site within an anterior approach. In 8 adult cadavers (16 sides), lines were used to connect the superior angle of the scapula, the acromion, and the coracoid process tip thus creating an anatomic triangle. The suprascapular nerve's entrance into the suprascapular foramen was documented regarding its position within this anatomical triangle. Depths from the skin surface and specifically from the medial-most point of the clavicular attachment of the trapezius to the suprascapular nerve's entrance into the suprascapular foramen were measured using calipers and a ruler. The clavicle was then fractured and retracted superiorly to verify the position of the nerve's entrance into the suprascapular foramen. From the trapezius, the nerve's entrance into the foramen was 3 to 4.2 cm deep (mean, 3.5 cm). The mean distance from the tip of the corocoid process to the suprascapular foramen was 3.8 cm. The angle best used to approach the suprascapular foramen from the surface was 15° to 20°. Based on our study, an anterior suprascapular approach to the suprascapular nerve as it enters the suprascapular foramen can identify the most medial fibers of the trapezius attachment onto the clavicle and insert a finger at an angle of 15° to 20° laterally and advanced to an average depth of 3.5 cm. Copyright © 2017 by the Congress of Neurological Surgeons

  8. Toxic anterior-segment syndrome (TASS

    Directory of Open Access Journals (Sweden)

    Cetinkaya S

    2014-10-01

    Full Text Available Servet Cetinkaya,1 Zeynep Dadaci,2 Hüsamettin Aksoy,3 Nursen Oncel Acir,2 Halil Ibrahim Yener,4 Ekrem Kadioglu5 1Ophthalmology Clinics, Turkish Red Crescent Hospital, Konya, 2Department of Ophthalmology, Faculty of Medicine, Mevlana University, Konya, 3Ophthalmology Clinics, Karaman State Hospital, Karaman, 4Konya Eye Center Hospital, Konya, 5Ophthalmology Clinics, Beyhekim State Hospital, Konya, Turkey Purpose: To evaluate the clinical findings and courses of five patients who developed toxic anterior-segment syndrome (TASS after cataract surgery and investigate the cause.Materials and methods: In May 2010, on the same day, ten patients were operated on by the same surgeon. Five of these patients developed TASS postoperatively.Results: Patients had blurred-vision complaints on the first day after the operation, but no pain. They had different degrees of diffuse corneal edema, anterior-chamber reaction, fibrin, hypopyon, iris atrophies, and dilated pupils. Their vision decreased significantly, and their intraocular pressures increased. Both anti-inflammatory and antiglaucomatous therapies were commenced. Corneal edema and inflammation resolved in three cases; however, penetrating keratoplasty was needed for two cases and additional trabeculectomy was needed for one case. Although full investigations were undertaken at all steps, we could not find the causative agent.Conclusion: TASS is a preventable complication of anterior-segment surgery. Recognition of TASS, differentiating it from endophthalmitis, and starting treatment immediately is important. Controlling all steps in surgery, cleaning and sterilization of the instruments, and training nurses and other operation teams will help us in the prevention of TASS. Keywords: cataract, phacoemulsification, TASS, corneal edema, inflammation

  9. A closed unventilated chamber for the measurement of transepidermal water loss.

    Science.gov (United States)

    Nuutinen, Jouni; Alanen, Esko; Autio, Pekka; Lahtinen, Marjo-Riitta; Harvima, Ilkka; Lahtinen, Tapani

    2003-05-01

    Open chamber systems for measuring transepidermal water loss (TEWL) have limitations related to ambient and body-induced airflows near the probe, probe size, measurement sites and angles, and measurement range. The aim of the present investigation was to develop a closed chamber system for the TEWL measurement without significant blocking of normal evaporation through the skin. Additionally, in order to use the evaporimeter to measure evaporation rates through other biological and non-biological specimens and in the field applications, a small portable, battery-operated device was a design criteria. A closed unventilated chamber (inner volume 2.0 cm(3) was constructed. For the skin measurement, the chamber with one side open (open surface area 1.0 cm(2) is placed on the skin. The skin application time was investigated at low and high evaporation rates in order to assess the blocking effect of the chamber on normal evaporation. From the rising linear part of the relative humidity (RH) in the chamber the slope was registered. The slope was calibrated into a TEWL value by evaporating water at different temperatures and measuring the water loss of heated samples with a laboratory scale. The closed chamber evaporation technique was compared with a conventional evaporimeter based on an open chamber method (DermaLab), Cortex Technology, Hadsund, Denmark). The reproducibility of the closed chamber method was measured with the water samples and with volar forearm and palm of the hand in 10 healthy volunteers. The skin application time varied between 7 and 9 s and the linear slope region between 3 and 5 s at the evaporation rates of 3-220 g/m(2) h. A correlation coefficient between the TEWL value from the closed chamber measurements and the readings of the laboratory scale was 0.99 (P measurements with the water samples was 4.0% at the evaporation rate of 40 g/m(2) h. A correlation coefficient of the TEWL values between the closed chamber and open chamber measurements was 0

  10. DELPHI's Ring Imaging Cherenkov Chamber

    CERN Multimedia

    1989-01-01

    The hundreds of mirrors around this Ring Imaging Cherenkov Chamber reflect cones of light created by fast moving particles to a detector. The velocity of a particle can be measured by the size of the ring produced on the detector. DELPHI, which ran from 1989 to 2000 on the LEP accelerator, was primarily concerned with particle identification.

  11. Bubble chamber: colour enhanced tracks

    CERN Document Server

    1998-01-01

    This artistically-enhanced image of real particle tracks was produced in the Big European Bubble Chamber (BEBC). Liquid hydrogen is used to create bubbles along the paths of the particles as a piston expands the medium. A magnetic field is produced in the detector causing the particles to travel in spirals, allowing charge and momentum to be measured.

  12. Testing an hydrogen streamer chamber

    CERN Multimedia

    1975-01-01

    A 2x10 cm gap streamer chamber, 35x55 cm2 in surface, was built and tested at CERN. Good tracks of cosmic rays were obtained up to atmospheric pressure, see F. Rohrbach et al, CERN-LAL (Orsay) Collaboration, Nucl. Instr. Methods 141 (1977) 229. Michel Cathenoz stand on the center.

  13. Chamber Music for Every Instrumentalist.

    Science.gov (United States)

    Latten, James E.

    2001-01-01

    Discusses why students who play musical instruments should participate in a chamber music ensemble. Provides rationale for using small ensembles in the high school band curriculum. Focuses on the topic of scheduling, illustrating how to insert small ensembles into the lesson schedule, and how to set up a new schedule. (CMK)

  14. A dual deformable reverberation chamber

    NARCIS (Netherlands)

    Leferink, Frank Bernardus Johannes

    2009-01-01

    There is disclosed an arrangement for measuring the effectiveness of a shielding material against electromagnetic fields. The arrangement comprises a first and a second reverberation chamber sharing a common wall. The common wall is partly made of the shielding material. A first antenna is arranged

  15. Generation of reactive oxygen species in the anterior eye segment. Synergistic codrugs of N-acetylcarnosine lubricant eye drops and mitochondria-targeted antioxidant act as a powerful therapeutic platform for the treatment of cataracts and primary open-angle glaucoma

    Directory of Open Access Journals (Sweden)

    Mark A. Babizhayev

    2016-12-01

    Mitochondrial targeting of compounds with universal types of antioxidant activity represents a promising approach for treating a number of ROS-related ocular diseases of the aging eye and can be implicated in the management of cataracts and primary open-angle glaucoma.

  16. [Anterior guidance in complete dentures].

    Science.gov (United States)

    Dubreuil, J; Trevelo, A

    1990-01-01

    Although the anterior guidance in complete dentures is not really a guide, the arrangement of the anterior maxillary and mandibular prosthetic teeth, defines a propulsive line called the virtual anterior guidance, a part from the cinematic criterias. The influence of this guide on cuspal movement is superior, in all mandibular points, to the influence of the condylar pathway. If this line is not respected, the practitioner may have to do excessive grindings during occlusal adjustments.

  17. Multidisciplinary management of anterior diastemata

    DEFF Research Database (Denmark)

    Furuse, Adilson Yoshio; Herkrath, Fernando José; Franco, Eduardo Jacomino

    2007-01-01

    Anterior diastemata may compromise the harmony of a patient's smile. Consideration of etiologic factors, previous gingival conditioning, and individual treatment planning are essential in the proper management of anterior diastemata. An integrated orthodontic-restorative approach may enhance...... the aesthetic results when orthodontic therapy itself is not feasible. This article presents integrated orthodonticrestorative solutions of anterior diastemata, associated with the conditioning of the gingival tissue with composite resin, and discusses the most relevant aspects related to their etiology...

  18. Hydrostatic Hyperbaric Chamber Ventilation System

    Science.gov (United States)

    Sarguisingh, Miriam J.

    2012-01-01

    The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy (HBOT) available in the developing world for the treatment of a variety of medical conditions. Specifically, HBOT is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. HBOT is simply too expensive and too dangerous to implement in the developing world using standard equipment. The HHC technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system to provide controlled pressurization and adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the patient and operating personnel, and physiological considerations. The simple schematic, comprised of easily acquired commercial hardware

  19. Posterior chamber volume does not change significantly during dilation.

    Science.gov (United States)

    Dorairaj, S; Liebmann, J M; Tello, C; Barocas, V H; Ritch, R

    2009-11-01

    To determine whether the volume of the posterior chamber changes during pupillary dilation. Eyes with anatomically narrow angles underwent ultrasound biomicroscopy of the posterior chamber and pupillary margin under dark- and light-room conditions to assess changes in posterior chamber anatomy and volume. All examinations were stored as real-time video. A frame-by-frame analysis was performed using a macro written for the ImageJ image-processing software. Thirteen eyes were assessed. The mean patient age was 63.0 (SD 10.0) years, and the mean refractive error was 1.1 (1.9) dioptres. The horizontal mean pupillary diameter was 2.3 (0.6) mm and 3.5 (0.5) mm under light- and dark-room conditions, respectively (pchamber volumes were unchanged under light and dark conditions (3.76 (1.09) vs 3.63 (0.78) mm(3), p = 0.22, paired t test). Volumes were greater under light conditions in eight eyes and under dark conditions in five eyes. The volume of the posterior chamber does not change significantly during dilation.

  20. Bioengineered anterior cruciate ligament

    Science.gov (United States)

    Altman, Gregory (Inventor); Kaplan, David (Inventor); Vunjak-Novakovic, Gordana (Inventor); Martin, Ivan (Inventor)

    2001-01-01

    The present invention provides a method for producing an anterior cruciate ligament ex vivo. The method comprises seeding pluripotent stem cells in a three dimensional matrix, anchoring the seeded matrix by attachment to two anchors, and culturing the cells within the matrix under conditions appropriate for cell growth and regeneration, while subjecting the matrix to one or more mechanical forces via movement of one or both of the attached anchors. Bone marrow stromal cells are preferably used as the pluripotent cells in the method. Suitable matrix materials are materials to which cells can adhere, such as a gel made from collagen type I. Suitable anchor materials are materials to which the matrix can attach, such as Goinopra coral and also demineralized bone. Optimally, the mechanical forces to which the matrix is subjected mimic mechanical stimuli experienced by an anterior cruciate ligament in vivo. This is accomplished by delivering the appropriate combination of tension, compression, torsion, and shear, to the matrix. The bioengineered ligament which is produced by this method is characterized by a cellular orientation and/or matrix crimp pattern in the direction of the applied mechanical forces, and also by the production of collagen type I, collagen type III, and fibronectin proteins along the axis of mechanical load produced by the mechanical forces. Optimally, the ligament produced has fiber bundles which are arranged into a helical organization. The method for producing an anterior cruciate ligament can be adapted to produce a wide range of tissue types ex vivo by adapting the anchor size and attachment sites to reflect the size of the specific type of tissue to be produced, and also adapting the specific combination of forces applied, to mimic the mechanical stimuli experienced in vivo by the specific type of tissue to be produced. The methods of the present invention can be further modified to incorporate other stimuli experienced in vivo by the

  1. Biomechanical effects of humeral neck-shaft angle and subscapularis integrity in reverse total shoulder arthroplasty.

    Science.gov (United States)

    Oh, Joo Han; Shin, Sang-Jin; McGarry, Michelle H; Scott, Jonathan H; Heckmann, Nathanael; Lee, Thay Q

    2014-08-01

    The variability in functional outcomes and the occurrence of scapular notching and instability after reverse total shoulder arthroplasty remain problems. The objectives of this study were to measure the effect of reverse humeral component neck-shaft angle on impingement-free range of motion, abduction moment, and anterior dislocation force and to evaluate the effect of subscapularis loading on dislocation force. Six cadaveric shoulders were tested with 155°, 145°, and 135° reverse shoulder humeral neck-shaft angles. The adduction angle at which bone contact occurred and the internal and external rotational impingement-free range of motion angles were measured. Glenohumeral abduction moment was measured at 0° and 30° of abduction, and anterior dislocation forces were measured at 30° of internal rotation, 0°, and 30° of external rotation with and without subscapularis loading. Adduction deficit angles for 155°, 145°, and 135° neck-shaft angle were 2° ± 5° of abduction, 7° ± 4° of adduction, and 12° ± 2° of adduction (P angles of humeral rotation and abduction moments were not statistically different between the neck-shaft angles. The anterior dislocation force was significantly higher for the 135° neck-shaft angle at 30° of external rotation and significantly higher for the 155° neck-shaft angle at 30° of internal rotation (P angle was more prone to scapular bone contact during adduction but was more stable at the internally rotated position, which was the least stable humeral rotation position. Subscapularis loading gave further anterior stability with all neck-shaft angles at all positions. Published by Mosby, Inc.

  2. Pencil-shaped radiation detection ionization chamber

    International Nuclear Information System (INIS)

    Suzuki, A.

    1979-01-01

    A radiation detection ionization chamber is described. It consists of an elongated cylindrical pencil-shaped tubing forming an outer wall of the chamber and a center electrode disposed along the major axis of the tubing. The length of the chamber is substantially greater than the diameter. A cable connecting portion at one end of the chamber is provided for connecting the chamber to a triaxial cable. An end support portion is connected at the other end of the chamber for supporting and tensioning the center electrode. 17 claims

  3. Corneoscleroplasty with maintenance of the angle in two cases of extensive corneoscleral disease.

    Science.gov (United States)

    Burk, R O; Joussen, A M

    2000-04-01

    We report a 2 year follow-up in two patients after corneoscleroplasty. Using lamellar corneoscleral dissection to maintain the drainage angle and its function, we performed a 14 mm allograft corneoscleroplasty in 2 eyes. For surgical treatment in both cases a 9.5 mm corneal button was excised from the recipient after peritomy and scleral lamellar preparation up to 14 mm. A 14 mm donor button was inserted and held in place with multiple Prolene sutures. One eye presented with a large perforating corneal ulcer after herpetic keratitis in a patient with recurrent rheumatoid uveitis associated with rubeosis iridis. The second eye had had a penetrating keratoplasty for keratoconus 30 years previously and presented with decompensating keratoglobus. Immune suppression was performed with systemic cyclosporin A and additional steroids when required. Both patients had a clear graft at the last follow-up visit and visual acuity was improved to a best corrected visual acuity of 0.6. Intraocular pressure in the keratoglobus eye was maintained at 6 mmHg without treatment, whereas the second case required continuing treatment with systemic acetazolamide because of neovascular glaucoma. The anterior chamber angles remained open in both patients. Contact lenses were helpful in the prevention of epithelial irregularities and defects. Both patients had an episode of immunological graft reaction which was reversed by immunosuppressive treatment. Phacoemulsification with intraocular lens implantation, which was performed 2 years after transplantation in the keratoglobus eye, did not affect the graft clarity or cause rejection episodes. Our results using corneoscleroplasty have been encouraging in severe destructive corneal disease.

  4. Comparative Study of Anterior Eye Segment Measurements with Spectral Swept-Source and Time-Domain Optical Coherence Tomography in Eyes with Corneal Dystrophies

    Directory of Open Access Journals (Sweden)

    Anna K. Nowinska

    2015-01-01

    Full Text Available Purpose. To compare anterior eye segment measurements and morphology obtained with two optical coherence tomography systems (TD OCT, SS OCT in eyes with corneal dystrophies (CDs. Methods. Fifty healthy volunteers (50 eyes and 54 patients (96 eyes diagnosed with CD (epithelial basement membrane dystrophy, EBMD = 12 eyes; Thiel-Behnke CD = 6 eyes; lattice CD TGFBI type = 15 eyes; granular CD type 1 = 7 eyes, granular CD type 2 = 2 eyes; macular CD = 23 eyes; and Fuchs endothelial CD = 31 eyes were recruited for the study. Automated and manual central corneal thickness (aCCT, mCCT, anterior chamber depth (ACD, and nasal and temporal trabecular iris angle (nTIA, tTIA were measured and compared with Bland-Altman plots. Results. Good agreement between the TD and SS OCT measurements was demonstrated for mCCT and aCCT in normal individuals and for mCCT in the CDs group. The ACD, nTIA, and tTIA measurements differed significantly in both groups. TBCD, LCD, and FECD caused increased CCT. MCD caused significant corneal thinning. FECD affected all analyzed parameters. Conclusions. Better agreement between SS OCT and TD OCT measurements was demonstrated in normal individuals compared to the CDs group. OCT provides comprehensive corneal deposits analysis and demonstrates the association of CD with CCT, ACD, and TIA measurements.

  5. Clinical Treatment of Chronic Condylar Dislocation by Restoring Anterior Guidance

    OpenAIRE

    澤田, 宏二; 荒井, 良明; メディナ, ラウル; 河野, 正司; 福井, 忠雄; 花田, 晃治; Sawada, Koji; Arai, Yoshiaki; Medina, Raul; Kohno, Shoji; Fukui, Tadao; Hanada, Kooji

    1997-01-01

    The mechanism of condylar dislocation is not exactly understood. Temporomandibular (TMJ) surgery is a common option in the treatment of chronic condylar dislocation, but some authors have reported disappearance of its symptomatology after occlusal treatment. A case in which condylar dislocation disappeared by changing the location of anterior guidance is presented. The patient was an 18 year-old male with an Angle class Ⅲ malocclusion who had been suffering from condylar dislocation of the ri...

  6. Morphometric Analysis of Bone Resection in Anterior Petrosectomies.

    Science.gov (United States)

    Ahmed, Osama; Walther, Jonathan; Theriot, Krystle; Manuel, Morganne; Guthikonda, Bharat

    2016-06-01

    Introduction The anterior petrosectomy is a well-defined skull base approach to lesions such as petroclival meningiomas, posterior circulation aneurysms, petrous apex lesions (chondrosarcomas, cholesteatomas), ventrolateral brainstem lesions, clival chordomas, trigeminal neurinomas, and access to cranial nerves III, IV, V, and VII. Methods and Materials Fourteen anterior petrosectomies on eight cadaveric heads were performed in a skull base dissection laboratory. Predissection and postdissection thin-cut computed tomography scans were obtained to compare the bone resection. A computer program was used (InVivo5, Anatomage, San Jose, California, United States) to measure the bone resection and the improved viewing angle. Results The average bone removed in each plane was as follows: anterior to posterior plane was 10.57 mm ± 2.00 mm, superior to inferior was 9.39 mm ± 1.67 mm, and lateral to medial was 17.46 mm ± 4.64 mm. The average increased angle of view was 13.01 ± 2.35 degrees (Table 1). The average volume was 1786.94 ± 827.40 mm(3). Conclusions Anterior petrosectomy is a useful approach to access the ventrolateral brainstem region. We present a cadaveric study quantitating the volume of bone resection and improvement in the viewing angle. These data provide useful preoperative information on the utility of this skull base approach and the gain in the viewing angle after bony removal.

  7. Comparison of three parallel plate ionization chambers for high energy electron dosimetry

    International Nuclear Information System (INIS)

    Rosenow, E.F.; Kasten, G.; Thienel, T.

    1994-01-01

    Various authors have claimed that the perturbation or replacement correction factor for the Markus electron dosimetry chamber drops from unity at higher electron energies to several per cent lower at the low energy end. Data gained from a comparison with cylindrical chambers showed a larger effect than those obtained from a comparison with Fricke dosimetry, indicating a systematic problem with cylindrical chambers. A similar controversy emerged in respect of the polarization effect. To confirm data obtained earlier and by others from Fricke dosimetry the perturbation effect of the Markus chambers was again measured. A drop of 2% was reconfirmed. Also, the small polarization effect was reconfirmed. For comparison and NACP and an Attix chamber were investigated. This investigation indicated a small margin for possible improvement of the Markus chamber. To separate the factors influencing the perturbation effect a number of modifications of the Markus chamber were examined. Guard ring size appeared to be only one parameter influencing the replacement correction, the others being collector diameter, plate separation, side wall angle, graphite coating and collector material. With small design modifications the perturbation effect of the Markus chamber can be made unity over the whole energy range while leaving basic characteristics such as the small sensitive volume, the negligible polarization effect and the outer dimensions unchanged. (author). 13 refs, 3 figs, 3 tabs

  8. LEP vacuum chamber, early prototype

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    The structure of LEP, with long bending magnets and little access to the vacuum chamber between them, required distributed pumping. This is an early prototype for the LEP vacuum chamber, made from extruded aluminium. The main opening is for the beam. The small channel to the right is for cooling water, to carry away the heat deposited by the synchroton radiation from the beam. The 4 slots in the channel to the left house the strip-shaped ion-getter pumps (see 7810255). The ion-getter pumps depended on the magnetic field of the bending magnets, too low at injection energy for the pumps to function well. Also, a different design was required outside the bending magnets. This design was therefore abandoned, in favour of a thermal getter pump (see 8301153 and 8305170).

  9. Development of multiwire proportional chambers

    CERN Document Server

    Charpak, G

    1969-01-01

    It has happened quite often in the history of science that theoreticians, confronted with some major difficulty, have successfully gone back thirty years to look at ideas that had then been thrown overboard. But it is rare that experimentalists go back thirty years to look again at equipment which had become out-dated. This is what Charpak and his colleagues did to emerge with the 'multiwire proportional chamber' which has several new features making it a very useful addition to the armoury of particle detectors. In the 1930s, ion-chambers, Geiger- Muller counters and proportional counters, were vital pieces of equipment in nuclear physics research. Other types of detectors have since largely replaced them but now the proportional counter, in new array, is making a comeback.

  10. Single wire drift chamber design

    Energy Technology Data Exchange (ETDEWEB)

    Krider, J.

    1987-03-30

    This report summarizes the design and prototype tests of single wire drift chambers to be used in Fermilab test beam lines. The goal is to build simple, reliable detectors which require a minimum of electronics. Spatial resolution should match the 300 ..mu..m rms resolution of the 1 mm proportional chambers that they will replace. The detectors will be used in beams with particle rates up to 20 KHz. Single track efficiency should be at least 99%. The first application will be in the MT beamline, which has been designed for calibration of CDF detectors. A set of four x-y modules will be used to track and measure the momentum of beam particles.

  11. The quadriceps angle

    DEFF Research Database (Denmark)

    Miles, James Edward; Frederiksen, Jane V.; Jensen, Bente Rona

    2012-01-01

    : Pelvic limbs from red foxes (Vulpes vulpes). METHODS: Q angles were measured on hip dysplasia (HD) and whole limb (WL) view radiographs of each limb between the acetabular rim, mid-point (Q1: patellar center, Q2: femoral trochlea), and tibial tuberosity. Errors of 0.5-2.0 mm at measurement landmarks...

  12. At Right Angles

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 9. At Right Angles. Shailesh A Shirali. Information and Announcements Volume 17 Issue 9 September 2012 pp 920-920. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/017/09/0920-0920 ...

  13. The lateral angle revisited

    DEFF Research Database (Denmark)

    Morgan, Jeannie; Lynnerup, Niels; Hoppa, R.D.

    2013-01-01

    This article presents the results of a validation study of a previously published method of sex determination from the temporal bone. The purpose of this study was to evaluate the lateral angle method for the internal acoustic canal for accurately determining the sex of human skeletal remains usi...... method appears to be of minimal practical use in forensic anthropology and archeology....

  14. Small angle neutron scattering

    International Nuclear Information System (INIS)

    Gupta, Sanjay

    1982-01-01

    The technique of small angle neutron scattering was first used in Germany less than two decades ago. Since then it has developed very rapidly, and today it is regarded as one of the most powerful techniques in materials, chemical and biological research. During the last decade the combination of high flux reactors and sophisticated instrumentation has revolutionized the technique. This paper endeavours to present a brief but comprehensive review of small angle scattering of neutrons and its applications in solid state research. The domain in which small angle neutron scattering is particularly useful is delineated and some of the methods used in the analysis of data are discussed with special emphasis on recent developments. Typical small angle neutron scattering cameras are described. Finally some experimental results on heterogeneities in metallic systems (both static and dynamic studies), radiation damage in materials, superconductivity, magnetic materials and the technologically very important area of non-destructive testing are reviewed in order to illustrate the wide range of applicability of this technique to problems in solid state research. (author)

  15. At Right Angles

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 9. At Right Angles. Shailesh A Shirali. Information and Announcements Volume 17 Issue 9 September 2012 pp 920-920. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/017/09/0920-0920 ...

  16. Influence of Reduced Mass Flow Rate and Chamber Backpressure on Swirl Injector Fluid Mechanics

    Science.gov (United States)

    Kenny, R Jeremy; Hulka, James R.

    2008-01-01

    Industry interest in variable-thrust liquid rocket engines places a demand on engine injector technology to operate over a wide range of liquid mass flow rates and chamber backpressures. One injection technology of current interest for variable thrust applications is an injector design with swirled fluids. Current swirl injector design methodologies do not take into account how swirl injector design parameters respond to elevated chamber backpressures at less than design mass flow rates. The current work was created to improve state-of-the-art swirl injector design methods in this area. The specific objective was to study the effects of elevated chamber backpressure and off-design mass flow rates on swirl injector fluid mechanics. Using a backpressure chamber with optical access, water was flowed through a swirl injector at various combinations of chamber backpressure and mass flow rates. The film thickness profile down the swirl injector nozzle section was measured through a transparent nozzle section of the injector. High speed video showed measurable increases in the film thickness profile with application of chamber backpressure and mass flow rates less than design. At prescribed combinations of chamber backpressure and injected mass flow rate, a discrete change in the film thickness profile was observed. Measured injector discharge coefficient values showed different trends with increasing chamber backpressure at low mass flow rates as opposed to near-design mass flow rates. Downstream spray angles showed classic changes in morphology as the mass flow rate was decreased below the design value. Increasing chamber backpressure decreased the spray angle at any injection mass flow rate. Experimental measurements and discussion of these results are reported in this paper.

  17. Anterior Commissure-posterior commissure revisited

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sang Han; Chi, Je Geun; Kim, Young Bo; Cho, Zang Hee [Neuroscience Research Institute, Gachon University of Medicine and Science, Incheon (Korea, Republic of)

    2013-08-15

    The anterior commissure (AC) and posterior commissure (PC) are the two distinct anatomic structures in the brain which are difficult to observe in detail with conventional MRI, such as a 1.5T MRI system. However, recent advances in ultra-high resolution MRI have enabled us to examine the AC and PC directly. The objective of the present study is to standardize the shape and size of the AC and PC using a 7.0T MRI and to propose a new brain reference line. Thirty-four, 21 males and 13 females, healthy volunteers were enrolled in this study. After determining the center of each AC and PC, we defined the connection of these centers as the central intercommissural line (CIL). We compared the known extra- and intra-cerebral reference lines with the CIL to determine the difference in the angles. Additionally, we obtained horizontal line from flat ground line of look front human. The difference in angle of the CIL and the tangential intercommissural line (TIL) from the horizontal line was 8.7 ± 5.1 (11 ± 4.8) and 17.4 ± 5.2 (19.8 ± 4.8) degrees in males and females, respectively. The difference in angle between the CIL and canthomeatal line was 10.1 in both male and female, and there was no difference between both sexes. Likewise, there was no significant difference in angle between the CIL and TIL between both sexes (8.3 +/- 1.1 in male and 8.8 +/- 0.7 in female). In this study, we have used 7.0T MRI to define the AC and PC quantitatively and in a more robust manner. We have showed that the CIL is a reproducible reference line and serves as a standard for the axial images of the human brain.

  18. Simulation studies on a prototype ionization chamber for measurement of personal dose equivalent, Hp(10)

    International Nuclear Information System (INIS)

    Cardoso, J.; Oliveira, C.; Carvalho, A.F.

    2005-01-01

    Full text: The Metrological Laboratory of lonizing Radiation and Radioactivity (LMRIR) of Nuclear and Technological Institute (ITN) has designed and constructed a prototype ionization chamber for direct measurement of the personal dose equivalent, H p (10), similar to the developed by the Physikalisch-Technische Bundesanstalt (PTB) and now commercialized by PTW. Tests already performed had shown that the behaviour of this chamber is very close to the PTB chamber, namely the energy dependence for the x-ray radiation qualities of the ISO 4037-1 narrow series N-30, N-40, N-60, N-80, N-100 and N-120 and also for gamma radiation of 137 Cs and 60 Co. However, the results obtained also show a high dependence on the energy for some incident radiation angles and a low magnitude of the electrical response of the ionization chamber. In order to try to optimize the performance of the chamber, namely to decrease the energy dependence and to improve the magnitude of the electrical response of the ionization chamber, the LMRIR initiated numerical simulation of this ionization chamber using a Monte-Carlo method for simulation of radiation transport using, in a first step, the MCNPX code. So, simulation studies of some physical parameters are been performed in order to optimize the response of the ionization chamber, namely the diameter of the central electrode of the ionization chamber, the thickness of the front wall of the ionization chamber, among others. Preliminary results show that probably the actual geometry of the ionization chamber is not yet the optimized configuration. The simulation study will carry on in order to find the optimum geometry. (author)

  19. Classification of anterior open bite using individualized cephalometry.

    Science.gov (United States)

    Bock, Jens Johannes; Bock, Franziska; Böhm, Bernhard; Fuhrmann, Robert A

    2005-09-01

    The objective of this study was to describe the cephalometric characteristics of the open bite, and to classify the open bite according to individualized norms. The lateral cephalograms of 134 patients with an anterior open bite (min -0.5 mm) were analyzed. Patients were classified according to the inclination of the jaws, applying the principles of individualized cephalometry. The harmony box described by Hasund was used to define individualized norms for the inclination of the upper and lower jaws in each patient. The open bite was classified into four sub-types: (1) dental, (2) skeletal with enlarged ML-NSL angle, (3) skeletal with reduced ML-NSL angle, and (4) skeletal with deviations in upper and lower jaws. A skeletal open bite was found in 89 patients (66.4%). A dental open bite was found in 45 patients (33.6%). A number of significant differences were found between these four groups using single-factor variance analysis and the Bonferroni a posteriori test, (p < or = 0.05, p < or = 0.01, p < or = 0.001). The most prominent variables were index value of anterior facial hight, total facial height ratio, gonial angle, and Y-axis. No significant differences were found for overbite, however. It was possible to use individualized norms to classify the open bite into four sub-types. The demarcation between the four groups was supported statistically. The extent of the anterior open bite does not allow any conclusions as to the craniofacial pattern.

  20. A mathematical model of aerosol holding chambers

    DEFF Research Database (Denmark)

    Zak, M; Madsen, J; Berg, E

    1999-01-01

    A mathematical model of aerosol delivery from holding chambers (spacers) was developed incorporating tidal volume (VT), chamber volume (Vch), apparatus dead space (VD), effect of valve insufficiency and other leaks, loss of aerosol by immediate impact on the chamber wall, and fallout of aerosol...... in the chamber with time. Four different spacers were connected via filters to a mechanical lung model, and aerosol delivery during "breathing" was determined from drug recovery from the filters. The formula correctly predicted the delivery of budesonide aerosol from the AeroChamber (Trudell Medical, London......-mentioned factors, initial loss of aerosol by impact on the chamber wall is most important for the efficiency of a spacer. With a VT of 195 mL, the AeroChamber and Babyhaler were emptied in two breaths, the NebuChamber in four breaths, and the Nebuhaler in six breaths. Insufficiencies of the expiratory valves were...

  1. The KEK 1 m hydrogen bubble chamber

    International Nuclear Information System (INIS)

    Doi, Yoshikuni; Araoka, Osamu; Hayashi, Kohei; Hayashi, Yoshio; Hirabayashi, Hiromi.

    1978-03-01

    A medium size hydrogen bubble chamber has been constructed at the National Laboratory for High Energy Physics, KEK. The bubble chamber has been designed to be operated with a maximum rate of three times per half a second in every two second repetition time of the accelerator, by utilizing a hydraulic expansion system. The bubble chamber has a one meter diameter and a visible volume of about 280 l. A three-view stereo camera system is used for taking photographic pictures of the chamber. A 2 MW bubble chamber magnet is constructed. The main part of the bubble chamber vessel is supported by the magnet yoke. The magnet gives a maximum field of 18.4 kG at the centre of the fiducial volume of the chamber. The overall system of the KEK 1 m hydrogen bubble chamber facility is described in some detail. Some operational characteristics of the facility are also reported. (auth.)

  2. GBO RF Anechoic Chamber & Antenna Test Range

    Data.gov (United States)

    Federal Laboratory Consortium — A shielded anechoic chamber measuring 15 by 15 by 37 feet is located in the Jansky Laboratory at Green Bank. This chamber has been outfitted as a far-field antenna...

  3. Projection chambers and dE/dx at ISABELLE

    International Nuclear Information System (INIS)

    White, D.H.; Benary, O.; Rosenson, L.; Roe, B.; Ditzler, W.R.; Watts, T.; Horwitz, N.

    1977-01-01

    The ''standard'' luminosity of 2 x 10 32 is taken as a goal for a device that measures charged particle momenta over a wide solid angle. It appears that a projection chamber is capable of operation in this mode providing care is taken to optimize the geometry with this high flux in mind. Some calculations have indicated that optimism is required but in no direction have the demands on the apparatus appeared to be well beyond those attainable. In addition dE/dx measurements yielding particle identification over the median momentum range, about 2 to 30 GeV/c, are also feasible

  4. Projection chambers and dE/dx at ISABELLE

    International Nuclear Information System (INIS)

    Alspector, J.; Ozaki, S.; Walenta, A.H.; White, D.H.; Benary, O.; Rosenson, L.; Roe, B.; Ditzler, W.R.; Watts, T.; Horwitz, N.

    1977-01-01

    The luminosity of 2 x 10 32 was taken as a goal for a device that measures charged particle momenta over a wide solid angle. It appears that a projection chamber is capable of operation in this mode, providing care is taken to optimize the geometry with this high flux in mind. Some calculations indicated that optimism is required, but in no direction have the demands on the apparatus appeared to be well beyond those attainable. In addition dE/dx measurements yielding particle identification over the median momentum range, about 2 to 30 GeV/c, are also feasible

  5. The HARP resistive plate chambers: Characteristics and physics performance

    CERN Document Server

    Ammosov, V; Chelkov, G; Dedovitch, D; Dydak, F; Elagin, A; Gapienko, V; Gostkin, M; Guskov, A; Koreshev, V; Kroumchtein, Z; Nefedov, Yu; Nikolaev, K; Semak, A; Sviridov, Yu; Usenko, E; Wotschack, J; Zaets, V; Zhemchugov, A

    2009-01-01

    The HARP resistive plate chamber (RPC) system was designed for time-of-flight measurement in the large-angle acceptance region of the HARP spectrometer. It comprised 46 four-gap glass RPCs covering an area of . The design of the RPCs, their operation, intrinsic properties, and system performance are described. The intrinsic time resolution of the RPCs is 127 ps leading to a system time-of-flight resolution of 175 ps. It is argued that gross differences between pion and proton timing in multi-gap timing RPCs, reported recently in the literature, do not exist.

  6. Inestabilidad Anterior de Hombro

    Directory of Open Access Journals (Sweden)

    Pablo David Flint Kuran

    2013-11-01

    Full Text Available In­tro­duc­ción La luxación recidivante de hombro es una patología frecuente en pacientes jóvenes, laboralmente activos. Existen numerosas técnicas quirúrgicas para la inestabilidad glenohumeral. La técnica de Bristow, discutida por no ser anatómica y por sus complicaciones, continúa vigente debido al bajo índice de reluxaciones. Los objetivos fueron determinar el índice de recidiva, alteraciones funcionales e índice de consolidación del injerto. Materiales­ y­ Métodos Se evaluaron 24 pacientes del sexo masculino, de entre 19 y 40 años, operados por luxación anterior recidivante de hombro según la técnica de Bristow, entre enero de 2003 y agosto de 2011. Se evaluó la tasa de reluxación, la función articular según el puntaje de Constant y el posicionamiento del injerto con respecto a la superficie articular con tomografía y radiografías para evaluar la consolidación del injerto. Se registraron las complicaciones quirúrgicas. Resultados ­Todos los pacientes eran hombres, con rango de edad de 19 a 40 años. La causa fue traumática en 24 pacientes. Dieciséis pacientes presentaron más de 3 episodios de luxación prequirúrgicos. Según la escala de Constant, 21 obtuvieron entre 96 y 100 puntos, y los restantes, entre 90 y 95 puntos. No hubo nuevos episodios de luxaciones. La tomografía mostró la consolidación en todos los casos. Un paciente tuvo una imagen osteolítica alrededor del tornillo, sin compromiso funcional del hombro. Conclusión La técnica de Bristow para tratar la luxación anterior recidivante de hombro provocó un bajo índice de complicaciones, con resultados funcionales entre excelentes y buenos. No hubo episodios de reluxación y se logró la consolidación del injerto óseo en todos los casos.

  7. Simple Cloud Chambers Using Gel Ice Packs

    Science.gov (United States)

    Kamata, Masahiro; Kubota, Miki

    2012-01-01

    Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry…

  8. Vacuum chamber at intersection I-6

    CERN Multimedia

    1971-01-01

    The vacuum chamber at intersection region I-6, one of these where experiments in colliding-beam physics will be taking place. The "wheels" prevent the thin wall (1.5 mm) of the chamber from collapsing. The chamber is equipped with heating tapes and its wrapped in thermal insulation. Residual gas pressure at this and other similar regions is around 10_11.

  9. Impedances in lossy elliptical vacuum chambers

    International Nuclear Information System (INIS)

    Piwinski, A.

    1994-04-01

    The wake fields of a bunched beam caused by the resistivity of the chamber walls are investigated for a vacuum chamber with elliptical cross section. The longitudinal and transverse impedances are calculated for arbitrary energies and for an arbitrary position of the beam in the chamber. (orig.)

  10. Vacuum chamber for an undulator straight section

    International Nuclear Information System (INIS)

    Kim, S.; Wehrle, R.; Genens, L.

    1987-01-01

    A prototype aluminum extruded vacuum chamber for an undulator straight section of the Advanced Photon Source is described. The 52.-m long vacuum system is designed so that the undulator gap variation does not interfere with it. The chamber is gripped in a stiff close toleranced mounting structure to insure dimensional tolerance of the chamber height

  11. Vacuum variable-angle far-infrared ellipsometer

    Science.gov (United States)

    Friš, Pavel; Dubroka, Adam

    2017-11-01

    We present the design and performance of a vacuum far-infrared (∼50-680 cm-1) ellipsometer with a rotating analyser. The system is based on a Fourier transform spectrometer, an in-house built ellipsometer chamber and a closed-cycle bolometer. The ellipsometer chamber is equipped with a computer controlled θ-2θ goniometer for automated measurements at various angles of incidence. We compare our measurements on SrTiO3 crystal with the results acquired above 300 cm-1 with a commercially available ellipsometer system. After the calibration of the angle of incidence and after taking into account the finite reflectivity of mirrors in the detector part we obtain a very good agreement between the data from the two instruments. The system can be supplemented with a closed-cycle He cryostat for measurements between 5 and 400 K.

  12. Construction and analysis of a prototype z drift chamber for the H1 experiment

    International Nuclear Information System (INIS)

    Robmann, P.; Meyer, C.A.; Boesiger, K.; Egli, S.; Koch, J.; Schmid, B.A.; Straumann, U.; Truoel, P.; Eichler, R.; Holzreuter, R.

    1989-01-01

    We discuss the construction and analysis of a novel wire arrangement, prototype z drift chamber for the H1 experiment at HERA (DESY). The final chamber will consist of fifteen 12 cm long rings along the z axis, each of which is a regular sixteenfold polygon in cross section. There are four sense wires and three guard wires per ring, and these wires lie in a plane tilted 45 0 from the normal. The final chamber needs to be able to measure accurate z information for polar angles, θ, between 20 0 and 170 0 . Using the tilted wire arrangement, and a sophisticated drift time to position conversion, we have achieved a resolution of about 320 μm which is virtually independent of the crossing angle. (orig.)

  13. Proportional chambers and multiwire drift chambers at high rates

    International Nuclear Information System (INIS)

    Walenta, A.H.

    1977-01-01

    The high event and particle rates expected for ISABELLE intersecting storage rings raise the question whether PWC's and drift chambers, now widely in use in experiments, still can operate under such conditions. Various effects depend on the number of avalanches produced per length of wire N and the size of the avalanche Q, i.e., on the number of positive ions created in an avalanche. Therefore the important parameter for the following discussion is the product QN. The minimum Q is determined by the type and noise level of preamplifiers used. Examples are given for a typical low noise amplifier as well as for a typical integrated ''cheap'' amplifier. The rate/wire length N depends on the chamber arrangement, wire spacing, etc. In multiwire drift chambers, a single wire shows space-charge effects reducing the pulse height by 1% at a rate of N = 7 x 10 3 mm -1 sec -1 . At a rate of N approximately equal to 10 5 mm -1 sec -1 an efficiency loss of the order of 1% was noticed. The aging effect due to deposits on the anode wire can be reduced using low noise amplifiers and low gas gain to such an extent that a lifetime of about half a year at ISABELLE can be expected. The use of conventional cheap preamplifiers will result in a typical lifetime of about 30 days. Improvements are probable. The time resolution of Δt/sub r/ = 4 nsec fwhm seems adequate for event rates of 10 7 sec -1 . The memory time Δt/sub m/ greater than or equal to 100 nsec may cause serious problems for pattern recognition depending on layout and readout. The use of induced signals on cathode pads, thus reading out shorter parts of the wire, can solve the problem

  14. Anterior ankle arthrodesis

    Science.gov (United States)

    Slater, Gordon L; Sayres, Stephanie C; O’Malley, Martin J

    2014-01-01

    Ankle arthrodesis is a common procedure that resolves many conditions of the foot and ankle; however, complications following this procedure are often reported and vary depending on the fixation technique. Various techniques have been described in the attempt to achieve ankle arthrodesis and there is much debate as to the efficiency of each one. This study aims to evaluate the efficiency of anterior plating in ankle arthrodesis using customised and Synthes TomoFix plates. We present the outcomes of 28 ankle arthrodeses between 2005 and 2012, specifically examining rate of union, patient-reported outcomes scores, and complications. All 28 patients achieved radiographic union at an average of 36 wk; the majority of patients (92.86%) at or before 16 wk, the exceptions being two patients with Charcot joints who were noted to have bony union at a three year review. Patient-reported outcomes scores significantly increased (P plate offers added compression and provides a rigid fixation for arthrodesis stabilization. PMID:24649408

  15. Precise measurement of scleral radius using anterior eye profilometry.

    Science.gov (United States)

    Jesus, Danilo A; Kedzia, Renata; Iskander, D Robert

    2017-02-01

    To develop a new and precise methodology to measure the scleral radius based on anterior eye surface. Eye Surface Profiler (ESP, Eaglet-Eye, Netherlands) was used to acquire the anterior eye surface of 23 emmetropic subjects aged 28.1±6.6years (mean±standard deviation) ranging from 20 to 45. Scleral radius was obtained based on the approximation of the topographical scleral data to a sphere using least squares fitting and considering the axial length as a reference point. To better understand the role of scleral radius in ocular biometry, measurements of corneal radius, central corneal thickness, anterior chamber depth and white-to-white corneal diameter were acquired with IOLMaster 700 (Carl Zeiss Meditec AG, Jena, Germany). The estimated scleral radius (11.2±0.3mm) was shown to be highly precise with a coefficient of variation of 0.4%. A statistically significant correlation between axial length and scleral radius (R 2 =0.957, pscleral radius. Lastly, no correlation was observed comparing scleral radius to the central corneal thickness (R 2 =0.047, p=0.161). Three-dimensional topography of anterior eye acquired with Eye Surface Profiler together with a given estimate of the axial length, can be used to calculate the scleral radius with high precision. Copyright © 2016 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  16. Vitrectorhexis and lens aspiration with posterior chamber intraocular lens implantation in spherophakia.

    Science.gov (United States)

    Al-Haddad, Christiane; Khatib, Lama

    2012-07-01

    We describe a technique that uses the vitrector to perform successful lens aspiration and posterior chamber intraocular lens (IOL) implantation in children with spherophakia and anterior lens subluxation. After an anterior chamber maintainer is placed, the ocutome is introduced through a limbal incision to perform a circular vitrectorhexis to avoid excessive manipulation of the unstable lens followed by gentle cortex aspiration. A foldable IOL is injected into the sulcus (3-piece IOL) or bag (1-piece IOL) if the capsule is sufficiently stable. Through a pars plana incision, the ocutome is then used to perform a posterior capsulotomy to prevent late posterior capsule opacification. In our patient, sulcus IOL placement was more stable than in-the-bag placement. Neither author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  17. Long-term changes in endothelial cell counts after early phacoemulsification versus laser peripheral iridotomy using sequential argon:YAG laser technique in acute primary angle closure.

    Science.gov (United States)

    Park, Hae-Young Lopilly; Lee, Na Young; Park, Chan Kee; Kim, Man Soo

    2012-11-01

    To compare the change in endothelial cell counts (ECC) after early phacoemulsification and laser peripheral iridotomy (LPI) using sequential argon:yttrium-aluminum-garnet (YAG) laser technique for the treatment of acute primary angle closure (APAC). This was a retrospective chart review, case-control study; 86 APAC patients were enrolled. Sixteen patients who underwent early phacoemulsification with intraocular lens implantation and 32 patients who underwent LPI were matched by propensity score analysis. All subjects underwent a complete ophthalmic examination, including intraocular pressure (IOP) measurements, optic disc examinations, and gonioscopy. ECC were acquired at the center of the cornea with a noncontact specular microscope before treatment, and at 1, 6, 12, and 24 months following phacoemulsification or LPI. The mean follow-up was 26.1 ± 4.7 months in the phacoemulsification group and 26.3 ± 4.5 months in the LPI group. After intervention, the changes in anterior chamber depth and Shaffer grading by gonioscopy were significantly different between groups. ECC were not different before treatment; however, after phacoemulsification or LPI at 12 months (2280 ± 320 vs 1993 ± 380 cells/mm(2)) and 24 months (2113 ± 333 vs 1880 ± 422 cells/mm(2)), there was a significant difference between the two groups (P = 0.040 and P = 0.032 respectively). Regression analysis showed that anterior chamber depth at baseline (P = 0.041) and intervention modality (phacoemulsification vs LPI; P APAC after a 2-year follow-up. In terms of ECC, early phacoemulsification could be a better intervention modality for APAC.

  18. A new reaction chamber for heavy ion, light particles - gamma ray coincidences

    International Nuclear Information System (INIS)

    Petrovici, M.; Simion, V.; Andronic, A.; Berceanu, I.; Buta, A.; Duma, M.; Moisa, D.; Pop, A.; Migneco, E.; Del Zoppo, A.; Bellia, G.

    1994-01-01

    Available as short communication only. In order to perform heavy ion, light particles -gamma ray coincidence measurements the experimental set-up DRACULA is foreseen to be connected with the gamma ray filter existing at LNS Catania. For this purpose a new reaction chamber was constructed. It consists of a spherical body (200 mm in diameter), an exit part toward the big ionization chamber, an entrance part having three beam pipes, a target holder part and an inspecting window. As one can see from the figure attached, the chamber gives the possibility to perform measurements at three different angles. Around the chamber a number of 13 big NaI(Tl) crystals and 4-6 Ge(Li) detectors hold by a special frame are foreseen to be installed. (Author) 1 Fig., 2 Refs

  19. Anterior segment indocyanine green angiography in anterior scleritis and episcleritis.

    Science.gov (United States)

    Guex-Crosier, Yan; Durig, Jacques

    2003-09-01

    To evaluate the pattern of anterior segment indocyanine green (ICG) angiography in episcleritis and scleritis. Prospective comparative (paired-eye) observational case series. Twenty subjects presenting clinical diseases compatible with episcleritis or scleritis. Anterior segment ICG angiography was performed according to a standard protocol in subjects presenting either episcleritis or scleritis. Photographs of the anterior segment were taken in the early phase (up to 3 minutes after dye injection), intermediate phase (10-12 minutes) and late phase (30-45 minutes). The inflamed zones were compared with the same regions of the controlateral eye. The amount of protein ICG exudation was scored by a masked observer as follows: zero for no exudation, one for slight exudation, two for moderate exudation, and three for severe exudation. Evaluation of dye leakage, which reflects protein exudation, with anterior segment ICG angiography in episcleritis and scleritis. Twenty subjects with a mean age of 43 +/- 15 years (7 male, 13 female) were enrolled in the study. Thirteen subjects had anterior scleritis (7 nodular, 5 diffuse, and 1 scleromalacia perforans), and 7 subjects had episcleritis. Only 1 out of 7 subjects with episcleritis showed a slight ICG leakage (a score of one), whereas all subjects with scleritis had ICG leakage scores of one or more (P = 0.0005, Fisher exact test). ICG angiography of the anterior segment of the eye is a good clinical test to differentiate episcleritis from scleritis.

  20. Correction of post-traumatic anterior open bite by injection of botulinum toxin type A into the anterior belly of the digastric muscle: case report.

    Science.gov (United States)

    Seok, Hyun; Park, Yong-Tae; Kim, Seong-Gon; Park, Young-Wook

    2013-08-01

    Post-traumatic anterior open bite can occur as a result of broken balance among the masticatory muscles. The superior hyoid muscle group retracts the mandible downward and contributes to the anterior open bite. Denervation of the digastric muscle by injection of botulinum toxin type A (BTX-A) can reduce the power of the digastric muscle and help to resolve the post-traumatic anterior open bite. A patient with a bilateral angle fracture had an anterior open bite even after undergoing three operations under general anesthesia and rubber traction. Although the open bite showed some improvement by the repeated operation, the occlusion was still unstable six weeks after the initial treatment. To eliminate the residual anterior open bite, BTX-A was injected into the anterior belly of the digastric muscle. Following injection of BTX-A, the anterior open bite showed immediate improvement. Complication and relapse were not observed during follow-up. Long-standing post-traumatic open bite could be successfully corrected by injection of BTX-A into the anterior belly of the digastric muscle without complication.

  1. Loss of ions in cavity ionization chambers

    International Nuclear Information System (INIS)

    Takata, N.; Tran, N.T.; Kim, E.; Marsoem, P.; Kurosawa, T.; Koyama, Y.

    2005-01-01

    Ion losses due to initial recombination, volume recombination, and back diffusion were each determined by measurements and calculations for different size cylindrical ionization chambers and spherical ionization chambers. By measuring signal currents from these ionization chambers irradiated with 60 Co gamma rays, two groups of ion losses were obtained. (Group 1) Ion loss due to initial recombination and diffusion, which changes proportionally to the inverse of the voltage applied to the ionization chambers; (and group 2) ion loss due to volume recombination, which changes proportionally to the inverse of the square of the applied voltage. The diffusion loss was obtained separately by computing electric field distributions in the ionization chambers. It was found that diffusion loss is larger than initial recombination loss for the cylindrical ionization chambers and vise versa for the spherical ionization chambers

  2. Growing and analyzing biofilms in flow chambers

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim; Sternberg, Claus

    2011-01-01

    conditions, and the environment can be carefully controlled and easily changed. The protocols in this unit include construction of the flow chamber and the bubble trap, assembly and sterilization of the flow chamber system, inoculation of the flow chambers, running of the system, image capture and analysis......This unit describes the setup of flow chamber systems for the study of microbial biofilms, and methods for the analysis of structural biofilm formation. Use of flow chambers allows direct microscopic investigation of biofilm formation. The biofilms in flow chambers develop under hydrodynamic......, and disassembly and cleaning of the system. In addition, embedding and fluorescent in situ hybridization of flow chamber-grown biofilms are addressed....

  3. TRU waste characterization chamber gloveboxes

    International Nuclear Information System (INIS)

    Duncan, D. S.

    1998-01-01

    Argonne National Laboratory-West (ANL-W) is participating in the Department of Energy's (DOE) National Transuranic Waste Program in support of the Waste Isolation Pilot Plant (WIPP). The Laboratory's support currently consists of intrusive characterization of a selected population of drums containing transuranic waste. This characterization is performed in a complex of alpha containment gloveboxes termed the Waste Characterization Gloveboxes. Made up of the Waste Characterization Chamber, Sample Preparation Glovebox, and the Equipment Repair Glovebox, they were designed as a small production characterization facility for support of the Idaho National Engineering and Environmental Laboratory (INEEL). This paper presents salient features of these gloveboxes

  4. Nova target chamber decontamination study

    International Nuclear Information System (INIS)

    1979-05-01

    An engineering study was performed to determine the most effective method for decontamination of the Nova target chamber. Manual and remote decontamination methods currently being used were surveyed. In addition, a concept that may not require in-situ decontamination was investigated. Based on the presently available information concerning material and system compatibility and particle penetration, it is recommended that a system of removable aluminum shields be considered. It is also recommended that a series of tests be performed to more precisely determine the vacuum compatibility and penetrability of other materials discussed in this report

  5. Experimental work on drift chambers

    International Nuclear Information System (INIS)

    Alcaraz, J.; Duran, I.; Gonzalez, E.; Martinez-Laso, L.; Olmos, P.

    1989-01-01

    An experimental work made on drift chambers is described in two chapters. In the firt chapter we present the description of the experimental installation used, as well as some details on the data adquisition systems and the characteristics on three ways used for calibration proposes (cosmic muons, β radiation and test beam using SPS at CERN facilities). The second chapter describes the defferent prototypes studied. The experimental set up and the analysis are given. Some results are discussed. The magnetic field effect is also studied. (Author)

  6. Effect of Posture on Hip Angles and Moments during Gait

    Science.gov (United States)

    Lewis, Cara L.; Sahrmann, Shirley A.

    2014-01-01

    Anterior hip pain is common in young, active adults. Clinically, we have noted that patients with anterior hip pain often walk in a swayback posture, and that their pain is reduced when the posture is corrected. The purpose of this study was to investigate a potential mechanism for the reduction in pain by testing the effect of posture on movement patterns and internal moments during gait in healthy subjects. Fifteen subjects were instructed to walk while maintaining three postures: 1) natural, 2) swayback, and 3) forward flexed. Kinematic and force data were collected using a motion capture system and a force plate. Walking in the swayback posture resulted in a higher peak hip extension angle, hip flexor moment and hip flexion angular impulse compared to natural posture. In contrast, walking in a forward flexed posture resulted in a decreased hip extension angle and decreased hip flexion angular impulse. Based on these results, walking in a swayback posture may result in increased forces required of the anterior hip structures, potentially contributing to anterior hip pain. This study provides a potential biomechanical mechanism for clinical observations that posture correction in patients with hip pain is beneficial. PMID:25262565

  7. Effect of posture on hip angles and moments during gait.

    Science.gov (United States)

    Lewis, Cara L; Sahrmann, Shirley A

    2015-02-01

    Anterior hip pain is common in young, active adults. Clinically, we have noted that patients with anterior hip pain often walk in a swayback posture, and that their pain is reduced when the posture is corrected. The purpose of this study was to investigate a potential mechanism for the reduction in pain by testing the effect of posture on movement patterns and internal moments during gait in healthy subjects. Fifteen subjects were instructed to walk while maintaining three postures: 1) natural, 2) swayback, and 3) forward flexed. Kinematic and force data were collected using a motion capture system and a force plate. Walking in the swayback posture resulted in a higher peak hip extension angle, hip flexor moment and hip flexion angular impulse compared to natural posture. In contrast, walking in a forward flexed posture resulted in a decreased hip extension angle and decreased hip flexion angular impulse. Based on these results, walking in a swayback posture may result in increased forces required of the anterior hip structures, potentially contributing to anterior hip pain. This study provides a potential biomechanical mechanism for clinical observations that posture correction in patients with hip pain is beneficial. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Modifying the hip abduction angle during bridging exercise can facilitate gluteus maximus activity.

    Science.gov (United States)

    Kang, Sun-Young; Choung, Sung-Dae; Jeon, Hye-Seon

    2016-04-01

    To investigate how the erector spinae (ES) and gluteus maximus (GM) muscle activity and the anterior pelvic tilt angle change with different hip abduction angles during a bridging exercise. Twenty healthy participants (10 males and 10 females, aged 21.6 ± 1.6) voluntarily participated in this study. Surface electromyography (EMG) signals were recorded from the ES and GM during bridging at three hip abduction angles: 0°, 15°, and 30°. Simultaneously, the anterior pelvic tilt angle was measured using Image J software. The EMG amplitude of the GM muscle and the GM/ES EMG ratio were greatest at 30° hip abduction, followed by 15° and then 0° hip abduction during the bridging exercise. In contrast, the ES EMG amplitude at 30° hip abduction was significantly lesser than that at 0° and 15° abduction. Additionally, the anterior pelvic tilt angle was significantly lower at 30° hip abduction than at 0° or 15°. Bridging with 30° hip abduction can be recommended as an effective method to selectively facilitate GM muscle activity, minimize compensatory ES muscle activity, and decrease the anterior pelvic tilt angle. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Anterior versus posterior approach in surgical treatment of tuberculous spondylodiscitis of thoracic and lumbar spine.

    Science.gov (United States)

    Hassan, Khaled; Elmorshidy, Essam

    2016-04-01

    The aim of this study is to compare the clinical, radiological and functional outcome of anterior versus posterior surgical debridement and fixation in patients with thoracic and lumbar tuberculous spondylodiscitis. A total number of 42 patients with tuberculous spondylodiscitis of the thoracic and lumbar spine treated surgically were included in this study. Twenty patients (group A) underwent anterior debridement, decompression and instrumentation by anterior approach. Twenty-two patients (group B) were operated by posterolateral (extracavitary) decompression and posterior instrumentation. Operative parameters, clinical, radiographic and functional results for the two groups were analyzed and compared. The average follow-up period was 15 months (range 12-24) in both groups. The average operative time, blood loss and blood transfusion of anterior group were significantly less than the posterior one. There was significant better back pain relief, kyphotic angle correction and less angle loss in the posterior group than anterior. There was no significant difference between the two groups regarding neurological recovery, functional outcome and fusion rate. Both anterolateral and posterolateral approaches are sufficient for achieving the goals of surgical treatment of thoracic and lumbar Pott's disease but posterolateral approach allows significant better kyphotic angle correction, less angle loss, better improvement in back pain but unfortunately more operative time and blood loss.

  10. Electron Identification and Energy Measurement with Emulsion Cloud Chamber

    Science.gov (United States)

    Kitagawa, Nobuko; Komatsu, Masahiro

    Charged particles undergo the Multiple Coulomb Scattering (MCS) when passing through a material. Their momentum can be estimated from the distribution of the scattering angle directly. Angle of electrons (or positrons) largely changes because of the energy loss in bremsstrahlung, and they are distinguished from other charged particles by making use of its feature. Electron energy is generally measured by counting of electromagnetic shower (e.m. shower) tracks in Emulsion Cloud Chamber (ECC), so enough absorber material is needed to develop the shower. In the range from sub-GeV to a few GeV, electrons don't develop noticeable showers. In order to estimate the energy of electrons in this range with a limited material, we established the new method which is based on the scattering angle considering the energy loss in bremsstrahlung. From the Monte Carlo simulation (MC) data, which is generated by electron beam (0.5 GeV, 1 GeV, 2 GeV) exposure to ECC, we derived the correlation between energy and scattering angle in each emulsion layer. We fixed the function and some parameters which 1 GeV MC sample would return 1 GeV as the center value, and then applied to 0.5 GeV and 2 GeV sample and confirmed the energy resolution about 50% within two radiation length.

  11. Anterior Knee Pain (Chondromalacia Patellae).

    Science.gov (United States)

    Garrick, James G.

    1989-01-01

    This article presents a pragmatic approach to the definition, diagnosis, and management of anterior knee pain. Symptoms and treatment are described. Emphasis is on active involvement of the patient in the rehabilitation exercise program. (IAH)

  12. Anterior approach for knee arthrography

    International Nuclear Information System (INIS)

    Zurlo, J.V.; Towers, J.D.; Golla, S.

    2001-01-01

    Objective. To develop a new method of magnetic resonance arthrography (MRA) of the knee using an anterior approach analogous to the portals used for knee arthroscopy.Design. An anterior approach to the knee joint was devised mimicking anterior portals used for knee arthroscopy. Seven patients scheduled for routine knee MRA were placed in a decubitus position and under fluoroscopic guidance a needle was advanced from a position adjacent to the patellar tendon into the knee joint. After confirmation of the needle tip location, a dilute gadolinium solution was injected.Results and conclusion. All the arthrograms were technically successful. The anterior approach to knee MRA has greater technical ease than the traditional approach with little patient discomfort. (orig.)

  13. Relationship between the angle of repose and angle of internal ...

    African Journals Online (AJOL)

    Abstract. Click on the link to view the abstract. Keywords: Angle of repose, angle of internal friction, granular materials, triaxial compression machine, moisture content. Tanzania J. Agric. Sc. (1998) Vol.1 No.2, 187-194 ...

  14. Limits to Drift Chamber Resolution

    CERN Document Server

    Riegler, Werner

    1998-01-01

    ATLAS (A Large Toroidal LHC Apparatus) will be a general-purpose experiment at the Large Hadron Collider that will be operational at CERN in the year 2004. The ATLAS muon spectrometer aims for a momentum resolution of 10% for a transverse momentum of pT=1TeV. The precision tracking devices in the muon system will be high pressure drift tubes (MDTs) with a single wire resolution of 1100 chambers covering an area of ≈ 2500m2. The high counting rates in the spectrometer as well as the aim for excellent spatial resolution and high efficiency put severe constraints on the MDT operating parameters. This work describes a detailed study of all the resolution limiting factors in the ATLAS environment. A ’full chain’ simulation of the MDT response to photons and charged particles as well as quantitative comparisons with measurements was performed. The good agreement between simulation and measurements resulted in a profound understanding of the drift chamber processes and the individual contributions to the spat...

  15. Neutron Detection with Bubble Chambers

    Science.gov (United States)

    Ghilea, M. C.; Lerche, R. A.; Disdier, L.

    2005-10-01

    To improve neutron imaging resolution, we have developed a general imaging design tool for inertial confinement fusion facilities that can simulate aperture errors, generate arbitrary neutron source distributions, simulate arbitrary aperture shapes, calculate point-spread functions using ray tracing, and reconstruct source images using a variety of filter functions. Predicted system performance can be compared to various concepts before construction. This software design tool is being developed for the UR/LLE OMEGA laser and the NIF as part of a process to design and build an imaging system based on a bubble chamber detectorootnotetextR. A. Lerche et al., Rev. Sci. Instrum. 74, 1709 (2003). for the UR/LLE OMEGA laser. This talk will present the latest results on aperture contributions to system performance and review the conceptual design of the bubble chamber-based imaging system, its conceptual design being reviewed in the second part of the presentation. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-92SF19460.

  16. Physicist makes muon chamber sing

    CERN Multimedia

    2007-01-01

    This Monitored Drift Tube detector, consisting of argon-CO2-filled aluminium tubes with a wire down the centre of each, will track muons in ATLAS; Tiecke used a single tube from one of these detectors to create the pipes in his organ. Particle physicists can make good musicians; but did you know particle detectors can make good music? That's what NIKHEF physicist Henk Tiecke learned when he used pipes cut from the ATLAS Monitored Drift Tube detector (MDT) to build his own working Dutch-style barrel organ in the autumn of 2005. 'I like to work with my hands,' said Tiecke, who worked as a senior physicist at NIKHEF, Amsterdam, on ZEUS until his retirement last summer. Tiecke had already constructed his barrel organ when he visited some colleagues in the ATLAS muon chambers production area at Nikhef in 2005. He noticed that the aluminium tubes they were using to build the chambers were about three centimetres in diameter-just the right size for a pipe in a barrel organ. 'The sound is not as nice as from wooden...

  17. Critical angle laser refractometer

    International Nuclear Information System (INIS)

    Castrejon-Pita, J.R.; Morales, A.; Castrejon-Garcia, R.

    2006-01-01

    A simple laser refractometer based on the detection of the critical angle for liquids is presented. The calibrated refractometer presents up to 0.000 11 of uncertainty when the refractive index is in the range between 1.300 00 and 1.340 00. The experimental setup is easy to construct and the material needed is available at most optics laboratories. The calibration method is simple and can be used in other devices. The refractive index measurements in aqueous solutions of sodium chloride were carried out to test the device and a linear dependence between the refractive index and the salt concentration was found

  18. Polymerase chain reaction in unilateral cases of presumed viral anterior uveitis

    Directory of Open Access Journals (Sweden)

    Shoughy SS

    2015-12-01

    Full Text Available Samir S Shoughy,1 Hind M Alkatan,2,4 Abdulelah A Al-Abdullah,2 Albarah El-Khani,2 Jolanda DF de Groot-Mijnes,3 Khalid F Tabbara1,4,5 1Department of Ophthalmology, The Eye Center and The Eye Foundation for Research in Ophthalmology, 2Department of Pathology & Laboratory Medicine and Uveitis Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia; 3Department of Virology and Ophthalmology, University Medical Center Utrecht, Utrecht, the Netherlands; 4Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia; 5The Wilmer Ophthalmological Institute of The Johns Hopkins University School of Medicine, Baltimore, MD, USA Background and objectives: Anterior uveitis is the most common form of intraocular inflammation. The main aim of this study was to determine the viral etiology in patients with unilateral cases of anterior uveitis.Patients and methods: A total of 12 consecutive patients with the diagnosis of idiopathic unilateral anterior uveitis were included prospectively. Aqueous specimens were obtained from each patient by anterior chamber paracentesis and subjected to the detection of viral DNA/RNA genome by polymerase chain reaction assay for herpes simplex virus, varicella zoster virus, cytomegalovirus, Epstein–Barr virus, and rubella virus.Results: There were six male and six female patients. The mean age was 43 years, with an age range of 11–82 years. All 12 cases presented with unilateral anterior uveitis. In four (33% patients, polymerase chain reaction was positive for viral genome. Two patients were positive for herpes simplex virus type 1, one patient was positive for cytomegalovirus and one for Epstein–Barr virus.Conclusion: Recent molecular diagnostic assays would help in the identification of the causative agent in patients with unilateral anterior uveitis. Keywords: viral anterior uveitis, PCR, herpes simplex virus, cytomegalovirus, diffuse keratic precipitates, anterior chamber

  19. Scaling of misorientation angle distributions

    DEFF Research Database (Denmark)

    Hughes, D.A.; Chrzan, D.C.; Liu, Q.

    1998-01-01

    The measurement of misorientation angle distributions following different amounts of deformation in cold-rolled aluminum and nickel and compressed stainless steel is reported. The sealing of the dislocation cell boundary misorientation angle distributions is studied. Surprisingly, the distributio...

  20. Magic angle spinning nuclear magnetic resonance apparatus and process for high-resolution in situ investigations

    Science.gov (United States)

    Hu, Jian Zhi; Sears, Jr., Jesse A.; Hoyt, David W.; Mehta, Hardeep S.; Peden, Charles H. F.

    2015-11-24

    A continuous-flow (CF) magic angle sample spinning (CF-MAS) NMR rotor and probe are described for investigating reaction dynamics, stable intermediates/transition states, and mechanisms of catalytic reactions in situ. The rotor includes a sample chamber of a flow-through design with a large sample volume that delivers a flow of reactants through a catalyst bed contained within the sample cell allowing in-situ investigations of reactants and products. Flow through the sample chamber improves diffusion of reactants and products through the catalyst. The large volume of the sample chamber enhances sensitivity permitting in situ .sup.13C CF-MAS studies at natural abundance.