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Sample records for anterior chamber depth

  1. Anterior chamber depth during hemodialysis

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    Gracitelli CPB

    2013-08-01

    Full Text Available Carolina Pelegrini Barbosa Gracitelli,1 Francisco Rosa Stefanini,1 Fernando Penha,1 Miguel Ângelo Góes,2 Sérgio Antonio Draibe,2 Maria Eugênia Canziani,2 Augusto Paranhos Junior1 1Ophthalmology Department, 2Division of Nephrology, Federal University of São Paulo – UNIFESP, São Paulo, Brazil Background: Exacerbation of chronic glaucoma or acute glaucoma is occasionally observed in patients undergoing hemodialysis (HD because of anterior chamber depth changes during this therapy. Purpose: To evaluate anterior chamber depth and axial length in patients during HD sessions. Methods: A total of 67 eyes of 35 patients were prospectively enrolled. Axial length and anterior chamber depth were measured using ultrasonic biometry, and these measures were evaluated at three different times during HD sessions. Body weight and blood pressure pre- and post-HD were also measured. Results: There was no difference in the axial length between the three measurements (P = 0.241. We observed a significantly decreased anterior chamber depth (P = 0.002 during HD sessions. Conclusion: Our results support the idea that there is a change in anterior chamber depth in HD sessions. Keywords: anterior chamber, hemodialysis, axial length, acute angle-closure glaucoma

  2. 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.

  3. The correlation between variation of visual acuity and the anterior chamber depth in the early period after phacoemulsification

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    Kai-jian CHEN

    2011-04-01

    Full Text Available Objective To investigate the correlation between the visual acuity variation and the anterior chamber depth in the early period after phacoemulsification.Methods Thirty-six eyes of 32 patients with age-related cataract underwent 3.2mm clear corneal incision phacoemulsification and intraocular lens(IOL implantation.The visual acuity was examined and horizontal curvature(K1,vertical curvature(K2,corneal astigmatism,and anterior chamber depth were measured with IOL-master preoperatively and also on 1,3,7 and 15 postoperative days.The changes in parameters were compared,and the correlations among visual acuity,corneal astigmatism and anterior chamber depth were analyzed.Results Before operation and 1d,3d,7d and 15d after operation,the corneal astigmatism was-0.87±0.40D,-1.92±1.38D,-1.69±1.13D,-1.45±0.79D and-1.36±0.74D;the anterior chamber depth was 3.08±0.35mm,4.04±0.38mm,4.28±0.29mm,4.22±0.17mm and 4.22±0.16mm;the visual acuity was 0.18±0.10,0.44±0.14,0.59±0.12,0.61±0.11 and 0.62±0.14.Significant difference was found between pre-operative and postoperative visual acuity,corneal astigmatism and anterior chamber depth,and it was also found in corneal astigmatism between 1d and 15d post operation(P < 0.05,as well as in anterior chamber depth and visual acuity between 1d and 3d post operation(P < 0.05.A positive correlation was found between visual acuity and corneal astigmatism on 1d(r=0.42,P < 0.05,3d(r=0.35,P < 0.05 and 7d(r=0.35,P < 0.05 post operation;and a negative correlation was found between visual acuity and anterior chamber depth on 3d(r=-0.29,P < 0.05,7d(r=-0.43,P < 0.01 and 15d(r=-0.37,P < 0.05 post operation.Conclusion Both the corneal astigmatism and the anterior chamber depth are correlated with the visual acuity variation in the early period after phacoemulsification.

  4. 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.

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

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

    2016-01-01

    Purpose 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. Methods 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. Results A strong linear correlation was found between EZR and ACD, R = −0.91, R2 = 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. Conclusions Lateral digital photography and EZR calculation is a novel method to quantitatively estimate ACD, requiring minimal equipment and training. Translational Relevance 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. PMID:27540496

  6. 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

  7. 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.

  8. Effect of anterior chamber depth on the choice of intraocular lens calculation formula in patients with normal axial length

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    Mohammad Miraftab

    2014-01-01

    Full Text Available Purpose: To compare the accuracy of  Sanders-Retzlaff-Kraff II (SRK II and 3 rd and 4 th generation intraocular lens (IOL formulas and to compare the effect of different anterior chamber depths among the IOL formulas in cataract patients with normal axial length (AL; 22.0-24.5 millimeters, mm. Materials and Methods: A retrospective chart review was performed of patients with normal AL who underwent cataract surgery. The SRK II and 3 rd generation IOL formulas (Hoffer Q, SRK T, Holladay 1 were compared to the 4 th generation Haigis formula. For analysis, preoperative anterior chamber depth (ACD was divided into three subgroups: ≤3, 3-3.5, and ≥ 3.5 mm. The mean error (ME and mean absolute error (MAE of each formula was compared for each subgroup against the total. The difference between the ME and MAE of the formulas were compared for each ACD subgroup. P 0.05, all comparisons. Conclusion: The SRK II formula can predict refraction in patients with normal AL and ACD less than 3 mm with less error and is preferred over other formulas. The Haigis formula is the preferred choice in patients with a normal AL and ACD longer than 3.5 mm. The prediction accuracy of Hoffer Q, SRK T, and Holladay 1 is comparable in normal AL.

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

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    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.

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

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    Huang, Jinhai; Lu, Weicong; Savini, Giacomo; Chen, Hao; Wang, Chengfang; Yu, Xinxin; Bao, Fangjun; Wang, Qinmei

    2016-01-01

    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. PMID:27403339

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

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    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.

  12. Short-term variation of central corneal thickness and axial anterior chamber depth of healthy eyes using Scheimpflug photography via the Oculus Pentacam*

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    S. D. Mathebula

    2009-12-01

    Full Text Available The purpose of this study was to investigate short-term variation and intra-subject repeatabil-ity of  human central corneal thickness (CCT and axial anterior chamber depth (AACD measure-ments obtained using the Oculus Pentacam. Forty consecutive images of the right eye of the anteriorsegment of 10 young and healthy individuals were measured with the Pentacam. Measurements of CCT and AACD were ob-tained from these images and means, standard deviations,variances and repeatability of the measurements were investigated. Both parameters (CCTand AACD showed small variation with good orexcellent repeatability for all eyes. The inter-subject or overall means and standard deviations for CCT and AACD of the 10 right eyes were 0.555 ±0.05 millimeters (or 555 ± 50 microns and 3.206± 0.04 millimeters, respectively. The individual or intra-subject averages for samples of CCT and AACD measurements are also provided in this paper. Univariate normality of the data was explored with Kolmogorov-Smirnov, Lilliefors and ShapiroWilks tests and we found that generally the data was normally distributed although there were some exceptions. Based on the results of this study, the Oculus Pentacam appears to provide repeatable and reliable measures for both CCT and AACD in young,normal eyes. Further research is, however, needed to determine short-term variation and repeatability of CCT and AACD with the Pentacam in more com-plicated eyes with, say, corneal scarring or ectasia or where refractive surgery may be an issue.

  13. Anterior Chamber Live Loa loa: Case Report.

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    Kagmeni, G; Cheuteu, R; Bilong, Y; Wiedemann, P

    2016-01-01

    We reported a case of unusual intraocular Loa loa in a 27-year-old patient who presented with painful red eye. Biomicroscopy revealed a living and active adult worm in the anterior chamber of the right eye. After surgical extraction under local anesthesia, parasitological identification confirmed L. loa filariasis.

  14. 角膜塑形镜对角膜前后表面曲率半径和前房深度的影响%The affect of orthokeratology lens to the anterior and posterior corneal surface and anterior chamber depth

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    陈蛟; 肖满意; 王华; 郭颖卓; 何书喜

    2013-01-01

      目的:探讨角膜塑形镜对角膜前后表面曲率半径和前房深度的影响。方法:用Orbscan-Ⅱ角膜地形图,检查17例31眼配戴角膜塑形镜3个月后角膜前后表面曲率半径和前房深度的变化。结果:配戴角膜塑形镜3个月后所有患者屈光度下降,裸眼视力上升(P0.05)。结论:角膜塑形镜主要通过改变角膜前表面的曲率,压平角膜前表面达到矫正近视的目的,对角膜后表面与前房深度无明显影响。%Objective To find out the affect of orthokeratology lens to the anterior and posterior corneal sur-face and anterior chamber depth.Methods 17 patients ,31eyes, after 3 months orthokeratology wearing, corneal topography examination with Orbscan-Ⅱ,record the changes of the anterior and posterior corneal surface radius and anterior chamber depth.Results After 3 months orthokeratology wearing, the refraction diopter decline, uncor-rected visual acuity increased (P0.05).Conclusion Orthokeratology lens mainly affects the shape of the anterior corneal surface , flatten the anteri-or corneal surface, rather than change of the posterior corneal surface radius and anterior chamber depth to achieve the effect of reducing refraction.

  15. Role of Optical Coherence Tomography in Assessing Anterior Chamber Angles

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    Kochupurakal, Reema Thomas; Jha, Kirti Nath; Rajalakshmi, A.R.; Nagarajan, Swathi; Ezhumalai, G.

    2016-01-01

    Introduction Gonioscopy is the gold standard in assessing anterior chamber angles. However, interobserver variations are common and there is a need for reliable objective method of assessment. Aim To compare the anterior chamber angle by gonioscopy and Spectral Domain Optical Coherence Tomography (SD-OCT) in individuals with shallow anterior chamber. Materials and Methods This comparative observational study was conducted in a rural tertiary multi-speciality teaching hospital. A total of 101 eyes of 54 patients with shallow anterior chamber on slit lamp evaluation were included. Anterior chamber angle was graded by gonioscopy using the shaffer grading system. Angles were also assessed by SD-OCT with Trabecular Iris Angle (TIA) and Angle Opening Distance (AOD). Chi-square test, sensitivity, specificity, positive and negative predictive value to find correlation between OCT parameters and gonioscopy grading. Results Females represented 72.7%. The mean age was 53.93 ±8.24 years and mean anterior chamber depth was 2.47 ± 0.152 mm. Shaffer grade ≤ 2 were identified in 95(94%) superior, 42(41.5%) inferior, 65(64.3%) nasal and 57(56.4%) temporal quadrants. Cut-off values of TIA ≤ 22° and AOD ≤ 290 μm were taken as narrow angles on SD-OCT. TIA of ≤ 22° were found in 88(92.6%) nasal and 87(87%) temporal angles. AOD of ≤ 290 μm was found in 73(76.8%) nasal and 83(83%) temporal quadrants. Sensitivity in detecting narrow angles was 90.7% and 82.2% for TIA and AOD, while specificity was 11.7% and 23.4%, respectively. Conclusion Individuals were found to have narrow angles more with SD-OCT. Sensitivity was high and specificity was low in detecting narrow angles compared to gonioscopy, making it an unreliable tool for screening. PMID:27190851

  16. Pupillary block glaucoma following implantation of a posterior chamber pseudophakos in the anterior chamber.

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    Mandal Anil

    2002-01-01

    Full Text Available Pupillary block glaucoma is a common complication of cataract surgery, especially following anterior chamber intraocular lens implantation. We report a case of pupillary block glaucoma with a posterior chamber IOL that was implanted in the anterior chamber following a complicated extracapsular cataract extraction. The case was successfully managed by explantation of the posterior chamber lens, anterior vitrectomy, peripheral iridectomy and secondary anterior chamber intraocular lens implantation. The intraocular pressure was controlled with a single topical antiglaucoma medication.

  17. Effect of primary iris and ciliary body cyst on anterior chamber angle in patients with shallow anterior chamber

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    Bing-hong WANG; Yu-feng YAO

    2012-01-01

    Objective:To evaluate the prevalence of primary iris and/or ciliary body cysts in eyes with shallow anterior chamber and their effect on the narrowing of the anterior chamber angle.Methods:Among the general physical check-up population,subjects with shallow anterior chambers,as judged by van Herick technique,were recruited for further investigation.Ultrasound biomicroscope (UBM) was used to detect and measure the cysts located in the iris and/or ciliary body,the anterior chamber depth (ACD),the angle opening distance at 500 μm (AOD500),and the trabecular-iris angle (TIA).A-scan ultrasonography was used to measure the ocular biometry,including lens thickness,axial length,lens/axial length factor (LAF),and relative lens position (RLP).The effect of the cyst on narrowing the corresponding anterior chamber angle and the entire angle was evaluated by the UBM images,ocular biometry,and gonioscopic grading.The eye with unilateral cyst was compared with the eye without the cyst for further analysis.Results:Among the 727 subjects with shallow anterior chamber,primary iris and ciliary body cysts were detected in 250 (34.4%) patients; among them 96 (38.4%) patients showed unilateral single cyst,21 (8.4%) patients had unilateral double cysts,and 42 (16.8%) patients manifested unilateral multiple and multi-quadrants cysts.Plateau iris configuration was found in 140 of 361 (38.8%) eyes with cysts.The mean size of total cysts was (0.6547±0.2319) mm.In evaluation of the effect of the cyst size and location on narrowing the corresponding angle to their position,the proportion of the cysts causing corresponding angle narrowing or closure among the cysts larger than 0.8 mm (113/121,93.4%) was found to be significantly higher than that of the cysts smaller than 0.8 mm (373/801,46.6%),and a significant higher proportion was also found in the cysts located at iridociliary sulcus (354/437,81.0%) than in that at the pars plicata (131/484,27.1%).In evaluating the effect

  18. 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

  19. Double anterior chamber in a patient with glaucoma and microspherophakia

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    Hamid Khakshoor

    2011-01-01

    Full Text Available We report the case of a 16-year-old woman with microspherophakia and secondary open angle glaucoma. The patient presented with a membrane dividing the anterior chamber into two segments without edema or Descemet′s membrane detachment. Slit lamp biomicroscopy, Pentacam, and specular microscopy images were obtained. Double anterior chamber is primarily found in patients with anterior chamber anomalies when there is no history of surgery or trauma.

  20. 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

  1. Method for measuring anterior chamber volume by image analysis

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    Zhai, Gaoshou; Zhang, Junhong; Wang, Ruichang; Wang, Bingsong; Wang, Ningli

    2007-12-01

    Anterior chamber volume (ACV) is very important for an oculist to make rational pathological diagnosis as to patients who have some optic diseases such as glaucoma and etc., yet it is always difficult to be measured accurately. In this paper, a method is devised to measure anterior chamber volumes based on JPEG-formatted image files that have been transformed from medical images using the anterior-chamber optical coherence tomographer (AC-OCT) and corresponding image-processing software. The corresponding algorithms for image analysis and ACV calculation are implemented in VC++ and a series of anterior chamber images of typical patients are analyzed, while anterior chamber volumes are calculated and are verified that they are in accord with clinical observation. It shows that the measurement method is effective and feasible and it has potential to improve accuracy of ACV calculation. Meanwhile, some measures should be taken to simplify the handcraft preprocess working as to images.

  2. Neovascular glaucoma treatment with extraction of anterior chamber fibrovascular tissue.

    Science.gov (United States)

    Nadal, Jeroni; Carreras, Elisa; Kudsieh, Bachar; Canut, Maribel

    2013-08-01

    The use of antibody to vascular endothelial growth factor to treat neovascular glaucoma yields good anatomic results in most cases. However, this type of glaucoma can cause angle closure with decompensation of intraocular pressure secondary to fibrovascular tissue contraction in the anterior chamber. Our surgical technique treats the cause by removing the anterior chamber fibrous complex after administration of antibody to vascular endothelial growth factor, thus restoring the chamber angle.

  3. Anterior chamber lenses. Part II: A laboratory study.

    Science.gov (United States)

    Apple, D J; Hansen, S O; Richards, S C; Ellis, G W; Kavka-Van Norman, D; Tetz, M R; Pfeffer, B R; Park, R B; Crandall, A S; Olson, R J

    1987-03-01

    An analysis of 606 surgically removed anterior chamber intraocular lens (IOL) specimens revealed that 351 or 58% of these were small-diameter, round loop, closed-loop styles. Because of the extremely high percentage of IOLs with this design received in our laboratory and the correlation of clinical histories with our histopathologic findings, we have concluded that such IOLs do not provide the safety and efficacy achieved by other anterior chamber lens designs. The finely polished, one-piece, all-PMMA styles fared well in our study. Although these one-piece styles comprise well over 50% of the American market share of anterior chamber IOLs, they comprise only 14% of all anterior chamber IOLs accessioned in our laboratory, compared to 58% for closed-loop designs. We believe that implantation of anterior chamber lenses with small-diameter, round, closed loops is no longer warranted. Patients in whom these IOLs have already been implanted should be carefully followed. It is our opinion that the FDA should recall or closely monitor all IOLs of this design and that implantation of closed-loop lenses should be discontinued in the United States. Furthermore, we believe that an IOL deemed to be not medically sound or worthy of implantation in the United States should not be marketed or donated outside of this country.

  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. Spontaneous Scleral Perforation of an Anterior Chamber Intraocular Lens

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    Oriel Spierer

    2016-05-01

    Full Text Available A routine eye examination of a 69-year-old man revealed a scleral perforation of one of the haptics of the anterior chamber intraocular lens (AC IOL which had been implanted many years ago. The patient was asymptomatic with good visual acuity. His history was negative for any trauma, eye rubbing, topical corticosteroid use, or autoimmune disease. The horizontal and vertical white-to-white diameters of the cornea in the right eye were 11.5 and 10.5 mm, respectively. Anterior segment optical coherence tomography showed the anterior chamber length to be 12.28 mm horizontally and 10.63 mm vertically. The patient underwent an IOL exchange, and the length of the explanted AC IOL was measured to be 12 mm. We speculate that the AC IOL, which was vertically aligned, was oversized. This case demonstrates the need for proper sizing and positioning of an AC IOL. In complex cases where AC IOL may be used, measuring the horizontal and vertical lengths of the anterior chamber by anterior segment optical coherence tomography prior to surgery may be useful.

  6. Spontaneous Scleral Perforation of an Anterior Chamber Intraocular Lens

    Science.gov (United States)

    Spierer, Oriel; O'Brien, Terrence P.

    2016-01-01

    A routine eye examination of a 69-year-old man revealed a scleral perforation of one of the haptics of the anterior chamber intraocular lens (AC IOL) which had been implanted many years ago. The patient was asymptomatic with good visual acuity. His history was negative for any trauma, eye rubbing, topical corticosteroid use, or autoimmune disease. The horizontal and vertical white-to-white diameters of the cornea in the right eye were 11.5 and 10.5 mm, respectively. Anterior segment optical coherence tomography showed the anterior chamber length to be 12.28 mm horizontally and 10.63 mm vertically. The patient underwent an IOL exchange, and the length of the explanted AC IOL was measured to be 12 mm. We speculate that the AC IOL, which was vertically aligned, was oversized. This case demonstrates the need for proper sizing and positioning of an AC IOL. In complex cases where AC IOL may be used, measuring the horizontal and vertical lengths of the anterior chamber by anterior segment optical coherence tomography prior to surgery may be useful. PMID:27462251

  7. Spontaneous Scleral Perforation of an Anterior Chamber Intraocular Lens.

    Science.gov (United States)

    Spierer, Oriel; O'Brien, Terrence P

    2016-01-01

    A routine eye examination of a 69-year-old man revealed a scleral perforation of one of the haptics of the anterior chamber intraocular lens (AC IOL) which had been implanted many years ago. The patient was asymptomatic with good visual acuity. His history was negative for any trauma, eye rubbing, topical corticosteroid use, or autoimmune disease. The horizontal and vertical white-to-white diameters of the cornea in the right eye were 11.5 and 10.5 mm, respectively. Anterior segment optical coherence tomography showed the anterior chamber length to be 12.28 mm horizontally and 10.63 mm vertically. The patient underwent an IOL exchange, and the length of the explanted AC IOL was measured to be 12 mm. We speculate that the AC IOL, which was vertically aligned, was oversized. This case demonstrates the need for proper sizing and positioning of an AC IOL. In complex cases where AC IOL may be used, measuring the horizontal and vertical lengths of the anterior chamber by anterior segment optical coherence tomography prior to surgery may be useful.

  8. 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.

  9. 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.

  10. Outcomes of Phacoemulsification with Anterior Chamber Maintainer in Vitrectomized Eyes

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    Elif Betül Türkoğlu

    2012-07-01

    Full Text Available Pur po se: To evaluate the outcomes of phacoemulsification with anterior chamber maintainer in vitrectomized eyes with complicated cataract. Ma te ri al and Met hod: Twenty eyes of 20 patients who developed complicated cataract after pars plana vitrectomy (PPV were included in the study. Phacoemulsification with clear corneal incision and foldable intraocular lens implantation was performed. In group 1, anterior chamber maintainer (ACM was used during phacoemusification and in group 2, ACM was not used. Pre- and postoperative visual acuities as well as per- and postoperative complications were reviewed retrospectively. Re sults: Anterior chamber maintainer was used during the surgery in 12 (60% cases and was not used in 8 (40% cases. Phacoemulsification was performed 16.5±9.2 (4-40 months after PPV. Best-corrected visual acuities were between hand motions and 0.4 preoperatively and between counting fingers from 1 meter and 1.0 postoperatively in group 1. Best-corrected visual acuities were between hand motions and 0.1 preoperatively and between counting fingers from 1 meter and 0.8 postoperatively in group 2. Posterior capsule was ruptured in 1 eye peroperatively in group 1. In group 2, phacoemulsification was more difficult due to deep anterior chamber in 8 eyes and intraoperative complications were iris sphincter rupture in 1 eye and posterior capsule rupture in 1 eye. Mild corneal edema in 7 (58.3% eyes, fibrin reaction in 2 (16.6%, intraocular lens decentralization in 1 (8.3% and posterior capsule opacification in 4 (33.3% eyes were the postoperative complications in group 1. Mild corneal edema in 5 (62.5% eyes, fibrin reaction in 1 (12.5% and posterior capsule opacification in 2 (25% eyes were the postoperative complications in group 2. Dis cus si on: Complicated cataracts which may develop after PPV can be treated safely with phacoemulsification. Continuous irrigation during the surgery may provide a stable anterior chamber and prevents

  11. Anterior chamber fixation of a posterior chamber intraocular lens: A novel technique

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    A Sahap Kükner

    2014-01-01

    Full Text Available We aimed to evaluate the implantation of a posterior chamber intraocular lens (IOL in the anterior chamber (AC with the haptics passing through two iridectomies to the posterior chamber. A total of 33 eyes of 33 patients with inadequate posterior capsular support due to either previous aphakia or posterior capsular rupture during cataract extraction were included in the study. A double iridectomy was performed on all patients using a vitrectomy probe on the midperiphery of the iris. IOLs were implanted in the AC, and the haptics were passed through the iridectomies to the posterior chamber. The mean follow-up time was 25.3 months. AC hemorrhage occurred in five patients during the iridectomy procedure. Corneal edema was detected in eight of 14 patients with primary IOL insertions. Haptic dislocation was detected in only one patient. This technique may be a good alternative to scleral-fixated IOL implantation in eyes with aphakia.

  12. 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.

  13. 3D spectral imaging system for anterior chamber metrology

    Science.gov (United States)

    Anderson, Trevor; Segref, Armin; Frisken, Grant; Frisken, Steven

    2015-03-01

    Accurate metrology of the anterior chamber of the eye is useful for a number of diagnostic and clinical applications. In particular, accurate corneal topography and corneal thickness data is desirable for fitting contact lenses, screening for diseases and monitoring corneal changes. Anterior OCT systems can be used to measure anterior chamber surfaces, however accurate curvature measurements for single point scanning systems are known to be very sensitive to patient movement. To overcome this problem we have developed a parallel 3D spectral metrology system that captures simultaneous A-scans on a 2D lateral grid. This approach enables estimates of the elevation and curvature of anterior and posterior corneal surfaces that are robust to sample movement. Furthermore, multiple simultaneous surface measurements greatly improve the ability to register consecutive frames and enable aggregate measurements over a finer lateral grid. A key element of our approach has been to exploit standard low cost optical components including lenslet arrays and a 2D sensor to provide a path towards low cost implementation. We demonstrate first prototypes based on 6 Mpixel sensor using a 250 μm pitch lenslet array with 300 sample beams to achieve an RMS elevation accuracy of 1μm with 95 dB sensitivity and a 7.0 mm range. Initial tests on Porcine eyes, model eyes and calibration spheres demonstrate the validity of the concept. With the next iteration of designs we expect to be able to achieve over 1000 simultaneous A-scans in excess of 75 frames per second.

  14. [Biocompatibility and pharmacokinetics of hydroxypropyl methylcellulose (HPMC) in the anterior chamber of the rabbit eye].

    Science.gov (United States)

    Ehrich, W; Höh, H; Kreiner, C F

    1990-06-01

    The biocompatibility and pharmacokinetics of hydroxypropylmethylcellulose (HPMC) 2% (Adatocel) and Tylose 2% (MH 1000) were investigated. A modified anterior chamber implantation test on the rabbit eye is suitable for testing both the biocompatibility and the pharmacokinetics of visco-surgical substances. Both substances were well tolerated. From the fourth day onward, HPMC was no longer detectable in the anterior chamber by infrared spectroscopy.

  15. Anterior Chamber Contamination at the Conclusion of Phacoemulsification

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    Mohammad-Reza Soleimani

    2008-12-01

    Full Text Available

    PURPOSE: To evaluate anterior chamber aspirates at the conclusion of phacoemulsification and intraocular lens implantation (PE+IOL for bacterial and fungal contamination. METHODS: We prospectively evaluated 80 eyes of 80 patients undergoing routine PE+IOL by performing bacterial and fungal culture on aspirates obtained from the anterior chamber at the end of the surgery. RESULTS: Anterior chamber fluid aspirates were positive for bacteria in 5 eyes (6.33% with coagulase-negative staphylococcus being the most common organism (three eyes. No instance of positive fungus culture was observed. One of the culture-positive eyes developed postoperative uveitis which resolved during a week of treatment with topical corticosteroids and antibiotics.  None of the eyes developed endophthalmitis. CONCLUSION: In the current series, the rate of anterior chamber contamination by bacteria at the end of phacoemulsification was in the lower range reported by previous studies.  

  1. Spectral domain optical coherence tomography study of pearl-like lesions in the anterior chamber

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    Soliman W

    2012-06-01

    Full Text Available Wael Soliman*, Ehab I Wasfi*, Omar M AliDepartment of Ophthalmology, Assiut University Hospital, Assiut University, Assiut, Egypt*These authors contributed equally to this workAim: To study the morphological pattern of pearl-like lesions in the anterior chambers of children before and after management using anterior segment spectral domain optical coherence tomography (SD-OCT.Patients and methods: This was a prospective, observational cross-sectional study of patients presenting with peculiar pearl-like lesions in the anterior chamber of their eyes. 1 mL of betamethasone sodium phosphate (2 mg/mL and betamethasone dipropionate (5 mg/mL was injected subconjunctivally. Follow-ups of all patients were conducted for a period of 6 weeks. Anterior segment imaging was done using SD-OCT and also photo slit lamp before and after management.Results: Twelve eyes of 12 patients were included in this study. These patients presented with pearl-like lesions in the anterior chamber with signs of anterior uveitis. There was no history of ocular injury or tuberculosis in any patients. Six weeks after subconjunctival steroid injection, all patients achieved mean best-corrected visual acuity, which changed from 0.2 (range 0.1–0.4 to 0.5 (range 0.4–0.8, and the severity of iritis decreased. SD-OCT showed that the lesions at presentation appeared as a globular noncystic mass attached to the back of the cornea, encroaching on the angle of the eye, and attached to the anterior surface of the iris at some points.Conclusion: SD-OCT for imaging the anterior segment allowed us to exclude the cystic nature of this pearly lesion. Some similarities may exist between these pearly lesions and superficial phlyctenular keratitis, which may support the immunological and inflammatory origin of these lesions.Keywords: pearl-like lesions, anterior chamber, phlycten, anterior segment OCT

  2. Vitreous asteroid hyalosis prolapse into the anterior chamber simulating iris metastasis.

    Science.gov (United States)

    Shields, Carol L; Romanelli-Gobbi, Massi; Lally, Sara E; Shields, Jerry A

    2012-01-01

    Two asymptomatic elderly women who underwent cataract extraction 7 or more years previously and with intraocular lens placement presented with a linear bead-like white multinodular mass in the inferior angle simulating iris metastasis versus large inflammatory precipitates. There was no iris infiltration. In the first case, the posterior lens capsule was intact and there was no evidence of gelatinous vitreous in the anterior chamber, whereas in the second case, the capsule was open and there was gelatinous vitreous prolapse. In both cases, there was asteroid hyalosis in the vitreous. Both patients were diagnosed with prolapsed vitreous asteroid hyalosis into the anterior chamber and managed with observation. Vitreous asteroid hyalosis can prolapse into the anterior chamber of pseudophakic elderly patients with or without capsular opening and can simulate an intraocular tumor.

  3. Vitreous asteroid hyalosis prolapse into the anterior chamber simulating iris metastasis

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    Carol L Shields

    2012-01-01

    Full Text Available Two asymptomatic elderly women who underwent cataract extraction 7 or more years previously and with intraocular lens placement presented with a linear bead-like white multinodular mass in the inferior angle simulating iris metastasis versus large inflammatory precipitates. There was no iris infiltration. In the first case, the posterior lens capsule was intact and there was no evidence of gelatinous vitreous in the anterior chamber, whereas in the second case, the capsule was open and there was gelatinous vitreous prolapse. In both cases, there was asteroid hyalosis in the vitreous. Both patients were diagnosed with prolapsed vitreous asteroid hyalosis into the anterior chamber and managed with observation. Vitreous asteroid hyalosis can prolapse into the anterior chamber of pseudophakic elderly patients with or without capsular opening and can simulate an intraocular tumor.

  4. Extraction of Iron from the Rabbit Anterior Chamber with Reverse Iontophoresis

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    Shoubin Sun

    2015-01-01

    Full Text Available Ocular siderosis is a common eye disease caused by retention of an iron-containing intraocular foreign body in the eye. Iron-containing intraocular foreign bodies may cause severe inflammatory reaction and affect visual function. Currently the optimal treatment method of ocular siderosis is a moot point. This study used the reverse iontophoresis technique to noninvasively extract iron from the rabbit anterior chamber. By slit lamp observation and histological examination, reverse iontophoresis treatment has a good effect on ocular siderosis. Reverse iontophoresis seems to be a noninvasive and promising approach to extract iron from the anterior chamber to treat ocular siderosis.

  5. Determination of relative ion chamber calibration coefficients from depth-ionization measurements in clinical electron beams

    Science.gov (United States)

    Muir, B. R.; McEwen, M. R.; Rogers, D. W. O.

    2014-10-01

    A method is presented to obtain ion chamber calibration coefficients relative to secondary standard reference chambers in electron beams using depth-ionization measurements. Results are obtained as a function of depth and average electron energy at depth in 4, 8, 12 and 18 MeV electron beams from the NRC Elekta Precise linac. The PTW Roos, Scanditronix NACP-02, PTW Advanced Markus and NE 2571 ion chambers are investigated. The challenges and limitations of the method are discussed. The proposed method produces useful data at shallow depths. At depths past the reference depth, small shifts in positioning or drifts in the incident beam energy affect the results, thereby providing a built-in test of incident electron energy drifts and/or chamber set-up. Polarity corrections for ion chambers as a function of average electron energy at depth agree with literature data. The proposed method produces results consistent with those obtained using the conventional calibration procedure while gaining much more information about the behavior of the ion chamber with similar data acquisition time. Measurement uncertainties in calibration coefficients obtained with this method are estimated to be less than 0.5%. These results open up the possibility of using depth-ionization measurements to yield chamber ratios which may be suitable for primary standards-level dissemination.

  6. 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), t

  7. Persistent corneal edema secondary to presumed dead adult filarial worm in the anterior chamber

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    Basak Samar

    2007-01-01

    Full Text Available We present three cases of persistent corneal edema secondary to presumed dead adult filarial worms lying in the anterior chamber with their attachment to the endothelium. Two of them were initially diagnosed as descemet′s fold with corneal edema. Two patients underwent penetrating keratoplasty and in one case, surgical removal was partly possible with clearing of cornea.

  8. [Intraocular lenses for the correction of refraction errors. Part 1: phakic anterior chamber lenses].

    Science.gov (United States)

    Kohnen, T; Baumeister, M; Cichocki, M

    2005-10-01

    In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss.

  9. Optical Coherence Tomography Findings in Anterior Chamber Ointment Globule after Phacoemulsification

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    Ahmad M. Mansour

    2015-12-01

    Full Text Available We present 2 cases of anterior chamber ointment with evidence of progressive endothelial cell loss. In both cases, an anterior segment optical coherence tomography (OCT was similar to an OCT of a tobramycin-dexamethasone ointment placed on a pen tip. An anterior segment OCT also demonstrated the direct contact of the globule with the corneal endothelium. A gas chromatography/mass spectrometry analysis documented the similarity to tobramycin-dexamethasone ointment in 1 case. Anterior segment OCT can help in confirming the diagnosis. Corneal endothelial injury is a continuous process, and its clinical manifestation is related to the size of the globule, the initial endothelium count, and the duration of ointment contact, which is related to supine positioning. It is advisable to avoid ointments in the immediate postoperative period, especially in corneal wounds larger than 3 mm.

  10. Ultrastructural Observations of The Anterior Chamber Angle Tissues in Congenital Glaucoma

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    Eighteen trabeculectomy specimens of congenital glaucoma were examined by light and transimssion electron microscopy. The results showed that the primary anomalies in congenital glaucoma included the developmental defects of trabecular meshwork, excessive collagen fibrils in the trabecular matrix, shifting forward of ciliary muscle fibres and persistent mesenchymal tissues in the anterior-chamber angle. The authors also pointed out the importance of the secondary lesions of the trabecular meshwork in th...

  11. 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.

  12. Iris-claw intraocular lens implantation: Anterior chamber versus retropupillary implantation

    Science.gov (United States)

    Helvacı, Sezer; Demirdüzen, Selahaddin; Öksüz, Hüseyin

    2016-01-01

    Purpose: To compare the outcomes of anterior chamber and retropupillary implantation of iris-claw Artisan intraocular lenses (IOL). Design: Prospective, randomized, single-blinded study. Patients and Methods: Forty eyes of forty aphakic patients were enrolled. Patients were randomized into two groups. Each group includes twenty patients. Group 1 received anterior chamber Artisan IOL implantation. Group 2 received retropupillary Artisan IOL implantation. Preoperative and postoperative corrected distance visual acuity (CDVA), intraocular pressure (IOP), and all complications were noted and compared at 6 months follow-up. Results: Each two groups obtained a significant improvement in CDVA (P < 0.05). Four patients in Group 1 and five patients in Group 2 had significant but nonpermanent increase at IOP values. There were one and two pupillary irregularity in Group 1 and Group 2, respectively. In one patient, a shallow and inferior located retinal detachment were encountered in anterior chamber group. Conclusions: The results were not significantly different between the two fixation techniques for iris-claw lens. The surgery procedure is dependent to surgeon experience and eye's conditions. PMID:26953023

  13. Comparison of Biograph/Lenstar and IOL Master in the measurement of axial length, corneal curvature, and anterior chamber depth%Biograph/Lenstar与IOL Master测量眼轴、角膜曲率及前房深度的比较

    Institute of Scientific and Technical Information of China (English)

    黄锦海; 陈世豪; 温岱宗; 王勤美

    2011-01-01

    目的 比较两种光学相干生物测量仪Biograph/Lenstar和IOL Master测量眼轴(AL)、角膜曲率(K1、K2和Km)和前房深度(ACD)的差异,分析二者的一致性,为临床使用提供依据.方法 前瞻性临床研究.近视患者34例(68眼),等效球镜为-0.05~-10.00 D,平均(-4.11±2.31)D,分别应用Biograph/Lenstar和IOL Master进行AL、K1、K2、Km和ACD测量,两种仪器间以上指标的差异采用配对t检验,两种仪器间测量所得数据的相关性采用 Pearson相关分析,两种仪器间测量所得数据的一致性采用Bland-Altamn统计分析.结果 Biograph/Lenstar和IOL Master测量AL的平均值分别为(25.39±1.09)mm和(25.37±1.08)mm,差异具有统计学意义(t=8.855,P<0.01);两者间的K1、K2和Km差异均有统计学意义(t=2.511,P=0.014;t=-2.413,P=0.019;t=2.893,P=0.005);ACD值分别为(3.80±0.26)mm和(3.78±0.26)mm,差异无统计学意义.两种仪器间所有的测量参数均具有密切的线性相关(r均>0.9,P<0.01).两种方法测量AL和ACD一致性较好,而K1、K2和Km一致性较差.结论 Biograph/Lenstar测量眼部无明显器质性疾病人群的眼轴长度及前房深度与IOL Master具有良好的一致性.对角膜曲率的测量,两者测量一致性较差,使用中需结合临床意义进一步对仪器的适用范围加以判断.%Objective To assess the accuracy of axial length (AL), corneal curvature (K1, K2 and Km) and anterior chamber depth (ACD) measurements with the Biograph/Lenstar LS 900 biometer and the IOL Master. Methods In this prospective clinical study, 68 eyes of 34 myopes, whose spherical equivalent were -0.50-10.00 D, with an average of (-4.11±2.31)D. AL, K1, K2, Km and ACD of these myopes were measured with the Biograph/Lenstar and IOL Master biometer. Data were analyzed using a paired samples t test, linear regression and Bland-Altman plots. Results The mean AL and ACD measured by the Biograph/Lenstar and IOL Master were (25.39±1.09)mm, (25.37±1.08)mm, and (3

  14. Perfluorodecaline residue in the anterior chamber of a patient with an intact crystalline lens: a case report

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    Aydin Erdinc

    2008-01-01

    Full Text Available Abstract Background Perfluorocarbon liquids are frequently used as intraoperative tools in vitreoretinal surgery and may occasionally be retained in the vitreous cavity. We report a patient who underwent pars plana vitrectomy for a giant tear after receiving blunt trauma to his right eye and sustained postoperative perfluorocarbon liquid residue in the anterior chamber in spite of an intact crystalline lens. Case presentation Perfluorodecaline was used as a temporary retinal tamponade. Three weeks after the surgery, a residue of heavy liquid was observed in the anterior chamber, even though the patient had an intact crystalline lens without any tilt or dislocation. The remnant of the heavy liquid was taken out of the anterior chamber immediately to avoid secondary complications. Conclusion Presence of heavy liquids in the anterior chamber may be associated with zonular defects even though the patient has an intact crystalline lens.

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

    Science.gov (United States)

    Xiao, Hui; Luo, Jingyi; Zuo, Chengguo; Huang, Xiaobo; Huang, Jingjing; Mi, Lan; Zhang, Qingjiong; Liu, Xing

    2017-01-01

    Purpose 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). Methods 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). Results 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

  16. Endothelial keratoplasty for corneal decompensation leaded by a dexamethasone implant dislocation in anterior chamber

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    Fernanda Pacella

    2016-06-01

    Full Text Available Background: Dexamethasone intravitreal implant (DEX largely showed his safety and efficacy for the treatment of cases of macular edema. Even if uncommon, delivery dislocation in anterior chamber has been described in Literaure as complication of the injection procedure, leading to irreversible endothelial cell loss in the majority of cases. We report a case of a 66-year-old man with pain and vision loss in his left eye. The anamnesis revealed a recent intravitreal injection of DEX implant for a persistent cystoid macular edema related to central retinal vein occlusion. Anterior segment examination showed corneal edema and the rod implant adherent to corneal endothelium. A large peripheral iridectomy was evident with retroillumination and IOL appeared good centered in the bag. The implant was removed but corneal decompensation was irreversible. One month later, an endothelial keratoplasty was successfully performed restoring corneal transparency. DEX intravitreal implant can migrate from vitreous cavity to anterior chamber and lead to irreversible corneal decompensation by mechanical and chemical toxicity on corneal endothelium. Removeal of the implant is necessary to avoid total endothelial decompensation. Despite this, in some cases endothelial keratoplasty had to be performed.

  17. The Relation of the Location of Haptics of Posterior Chamber Intraocular Lenses and Peripheral Anterior Synechia

    Institute of Scientific and Technical Information of China (English)

    RuiduanLiao; ShaozhenLi

    1995-01-01

    Purpose:To investigate the occurrence,outcome and influencial factors of the pe-ripheral anterior synechia(PAS)following implantation of posterior chamber in-traocular lenses for finding a way to reduce thePAS.Subjects;40 eyes of 38senile cataract patients with normal chamber angle and in-traocular pressue(IOP)preoperatively were examined.Methods:Extracapsular cataract extraction was performed under microscope with insertion of a posterior chamber lens implant vaulted anteriorly by 10°.Go-nioscopy and slit-lamp examination and photography of the operated eyes were performed 3to 6months postoperatively.Results:PAS were found in 20(50%)of the 40eyes.Among the 20eyes with PAS the locations of 23haptics in17eyes corresponded with those of the PAS.PAS were seen more frequently with vertically sulcus-fixated haptics than with the horizontally capsular-fixated haptics.showing a significant difference(P<0.05).88%of the eyes withPAS had pupillary edformation,but their visual acuities and IOP were not affected.Conclusions:PAS is more likely to occur with vertically sulcus-fixated IOL.Rotat-ing the capsular-fixated haptics to the horizontal position may reduce the inci-dence of PAS.Gonioscopy should be a routine follow-up examination.

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

    Science.gov (United States)

    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.

  19. Vitrectomy and translocation of the anterior chamber intraocular lens to the sulcus: a closed microsurgical technique for the UGH syndrome.

    Science.gov (United States)

    Gualtieri, William; Rossini, Paolo; Forlini, Cesare

    2008-01-01

    This interventional case report presents an anterior chamber intraocular lens (AC-IOL) translocation technique to manage a case of uveitis-glaucoma-hyphema (UGH) syndrome associated with posterior dislocation of nuclear fragments and vitreitis as a consequence of capsule rupture during cataract surgery. Pars plana vitrectomy followed by an AC-IOL translocation from the anterior chamber to the sulcus without additional surgical corneal incision was performed. At 12 months' follow-up, the original AC-IOL was in stable position in the posterior chamber, with binocular refractive balance and no further astigmatism and resolution of the UGH syndrome.

  20. Catarata polar anterior piramidal deslocada para a câmara anterior causando edema de córnea: relato de caso Corneal edema caused by a pyramidal anterior polar cataract dislocated to the anterior chamber: case report

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    Ramon Coral Ghanem

    2004-08-01

    Full Text Available Cataratas polares anteriores piramidais são opacidades cônicas que se projetam para a câmara anterior a partir da cápsula anterior do cristalino. Na grande maioria dos pacientes a opacidade permanece aderida e estável durante toda a vida. O objetivo deste trabalho é documentar uma manifestação incomum desse tipo de catarata: a deiscência espontânea das pirâmides para a câmara anterior causando descompensação endotelial e edema corneal bilateral. Relatamos o caso de uma paciente feminina, de 66 anos, branca, que apresentava edema corneal localizado inferiormente no olho direito associado à lesão nodular branco-esclerótica compatível com a pirâmide anterior da catarata polar. O olho esquerdo apresentava edema corneal difuso intenso e presença de uma catarata polar anterior com a região piramidal deslocada para a câmara anterior. Sabe-se que a pirâmide anterior pode permanecer inabsorvida na câmara anterior por longo período, pois é composta de tecido colágeno denso. Isto causa perda endotelial progressiva e edema corneal e deve ser considerada indicação de remoção cirúrgica da catarata polar anterior e de seu fragmento. Ressalta-se, também, a importância do bom senso no julgamento das cataratas polares anteriores, considerando-se tamanho da opacidade, simetria das opacidades e componente cortical associado, na tentativa de se evitar ambliopia.Pyramidal anterior polar cataracts are conical opacities that project into the anterior chamber from the anterior capsule of the lens. In the vast majority of patients the opacity remains bound and stable throughout life. We report an unusual complication of this type of cataract: spontaneous dehiscence of the pyramids to the anterior chamber causing bilateral endothelial damage and corneal edema. 66-year-old white woman presented with inferior corneal edema in the right eye and diffuse corneal edema in the left eye. A white nodular lesion was observed in the inferior angle

  1. GATA-3 expression in the development of anterior chamber associated immune deviation

    Institute of Scientific and Technical Information of China (English)

    FU Tao; YANG Pei-zeng; HUANG Xiang-kun; HUANG Qiang; ZHOU Hong-yan; LI Bing; ZHONG Hua-hong; CHEN Xuan

    2005-01-01

    Background Anterior chamber associated immune deviation (ACAID) is characterized by a Th2 cell response. GATA-3 has been shown to be necessary for the activation of Th2 cells. This study was designed to examine the expression of GATA-3 in the development of ACAID. Methods ACAID was induced by injection of 50 μg interphotoreceptor retinoid binding protein (IRBP) into the anterior chamber (AC) of Wistar rats. Delayed-type hypersensitivity (DTH) was evaluated on day 3, 7, 14, 21, 28 after IRBP inoculation. GATA-3 expression was detected using immunohistochemical staining. The expression of GATA-3 mRNA at different time points after AC injection of IRBP was assayed by reverse transcriptase polymerase chain reaction (RT-PCR). Results A significant DTH reaction was observed in Wistar rats on day 3 and 5 after IRBP inoculation. The DTH reaction was decreased 7 days after IRBP inoculation. GATA-3 expression was weak at both mRNA and protein levels in the normal spleen, but was significantly increased on day 5, 7, 14, and 21 after AC injection of IRBP. Conclusion The expression of GATA-3 is increased during ACAID, suggesting that GATA-3 may be involved in the development of ACAID.

  2. Fifty-year follow-up and Strampelli anterior chamber intraocular lens.

    Science.gov (United States)

    Oakley, Carmen L; Nigro, Matthew A; Vote, Brendan J

    2015-01-01

    The Strampelli anterior chamber intraocular lens was created in 1953, and was primarily used to treat myopia and aphakia. Due to the positioning of the lens, it was associated with a number of complications, and was later modified to decrease the rate of significant complications, including endothelial cell loss. This paper describes a 62-year-old man, who has had a Strampelli intraocular lens (IOL) in situ for 52 years, with relatively few complications. The case provides a framework for reflection on the significant advances in the development of IOLs since the Strampelli era. The Strampelli anterior chamber intraocular lens was created in 1953, and was primarily used to treat myopia and aphakia. Due to the positioning of the lens, it was associated with a number of complications, and was later modified to decrease the rate of significant complications, including endothelial cell loss. This paper describes a 62-year-old man, who has had a Strampelli intraocular lens (IOL) in situ for 52 years, with relatively few complications. The case provides a framework for reflection on the significant advances in the development of IOLs since the Strampelli era.

  3. 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.

  4. Evaluation of bacterial contamination rate of the anterior chamber during phacoemulsification surgery using an automated microbial detection system

    Institute of Scientific and Technical Information of China (English)

    Ibrahim; Kocak; Funda; Kocak; Bahri; Teker; Ali; Aydin; Faruk; Kaya; Hakan; Baybora

    2014-01-01

    ·AIM: To assess the incidence of anterior chamber bacterial contamination during phacoemulsification surgery using an automated microbial detection system(BacT/Alert).·METHODS: Sixty-nine eyes of 60 patients who had uneventful phacoemulsification surgery, enrolled in this prospective study. No prophylactic topical or systemic antibiotics were used before surgery. After antisepsis with povidone-iodine, two intraoperative anterior chamber aqueous samples were obtained, the first whilst entering anterior chamber, and the second at the end of surgery. BacT/Alert culture system was used to detect bacterial contamination in the aqueous samples.·RESULTS: Neither aqueous samples obtained at the beginning nor conclusion of the surgery was positive for microorganisms on BacT/Alert culture system. The rate of bacterial contamination during surgery was 0%. None of the eyes developed acute-onset endophthalmitis after surgery.· CONCLUSION: In this study, no bacterial contamination of anterior chamber was observed during cataract surgery. This result shows that meticulous surgical preparation and technique can prevent anterior chamber contamination during phacoemulsification cataract surgery.

  5. Short-term variation in ocular anterior chamber angle using Scheimpflug photography

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    A. Rubin

    2010-12-01

    Full Text Available Purpose: To investigate short-term variation of ocular Anterior Chamber Angle (ACA within and across the different meridians of young, healthy eyes.Method: Scheimpflug photography (via an  Oculus Pentacam was used to repeatedly measure the anterior segment of the right eyes of three young females, all aged 22 years.  For each individual, ten consecutive maps were determined over a short time period and each map contained information for the chamber angles of different meridians across the eye involved, roughly at 70 intervals.  Each meridian in an eye was thus measured 10 times in total permitting analysis of short-term variation both within and across the meridians concerned.  Parametric and non-parametric statistical methods used to understand short-term variation of ACA included meridional plots of medians andlower and upper quartiles (Q1 and Q3 and various polar plots (of raw observations, of means and 95%confidence regions, and of standard deviations.Results: Over, at least, short periods of time, Scheimpflug photography provided fairly repeatable results for ACA both within and across the meridians of the eyes involved.  However, occasionally outliers increased variability for some meridians.  While short-term variation within meridians was relatively small assuming exclusion of a limitednumber of outliers, variation across the meridians of specific eyes was greater (probably relating to the usual anatomical structure of eyes with ACA in the inferior quadrants being mostly larger than that for the superior quadrants.  Friedman ANOVA confirmed for each of the three eyes concerned thamedian ACA was significantly different across thvarious meridians.Conclusion: Scheimpflug photography allows for comprehensive, non-invasive and rapid measurement of ACA through 3600.  Repeatability of measurements appears satisfactory over the short-term, despite potential limitations relating to this photo-graphic method for measuring ACA.  The

  6. The Management of a Patient with Elevated Intraocular Pressure Resistant to Medical Treatment: Anterior Chamber Irrigation

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    Abdullah Beyoğlu

    2014-10-01

    Full Text Available A 7-year-old male patient was medically treated in another center for hyphema which occurred after blunt trauma to his right eye. He was admitted to our clinic when his visual acuity decreased after being discharged. Biomicroscopic examination revealed total hyphema. Intraocular pressure (IOP was 48 mm Hg in the right eye with Goldmann applanation tonometry. Since IOP could not be managed by medical therapy and there was no regression in hyphema, anterior chamber was irrigated. As in our case, it should not be forgotten that re-hemorrhage may occur in the first week of hyphema during childhood. Moreover, surgical treatment should be considered when hemorrhage does not regress with medical treatment, increased IOP persists, and when there is a risk of corneal endothelial staining (corneal blood staining. (Turk J Ophthalmol 2014; 44: 400-2

  7. Aphakia Correction by Injection of Foldable Intra Ocular Lens in The Anterior Chamber

    Science.gov (United States)

    Giles, Kagmeni; Ernest, Moukouri; Christelle, Domngang; Georges, Nguefack-Tsague; Raoul, Cheuteu; Come, Ebana Mvogo; Wiedemann, Peter

    2013-01-01

    We assessed the outcomes of the use of anterior chamber foldable lens for unilateral aphakia correction at the University Teaching Hospital of Yaounde. In this retrospective, non-comparative, consecutive case series study, we reviewed the records of patients who underwent an operation for aphakia correction by the means of injection of an angular supported foldable lens between January 2009 and December 2011 in the University Teaching Hospital Yaounde. Student’s paired t-test was carried out to compare pre-operative and post-operative visual acuity (VA) and intraocular pressure (IOP). P-values less than 0.05 were considered statistically significant. Twenty-one patients were included in the study; twelve were male (57.1%) and nine were female (42.9%). The mean age was 55.38 ± 17.67 years (range 9–75 years). The mean follow-up duration was 5.95 ± 3.14 months (range 2–12 months). The mean log-MAR visual acuity was 1.26 ± 0.46 pre-operatively and 0.78 ± 0.57 post-operatively (P = 0.003). The change in intraocular pressure was not statistically significant. Complications included intraocular hypertension (over 21 mmHg) in 3 patients (14.3%) and macular edema, pupillar ovalization, and retinal detachment in one patient each. The results indicate that injection of an angular support foldable lens in the anterior chamber is a useful technique for the correction of aphakia in eyes without capsular support. More extended follow-up, however, and a larger series of patients are needed to ascertain the effectiveness and safety of this procedure. PMID:24324349

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

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    Wenwen He

    2016-01-01

    Full Text Available 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 mm3 (range 59.41 to 254.09 mm3. 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<0.001, and Spearman’s correlation analysis, ρ=-0.450, P<0.001. ACV was also increased with AXL (Pearson’s correlation analysis, r=0.552, P<0.001. Multiple linear regression showed that, with all of the covariates entered into the model, gender (P=0.002, age (P=0.015, LOCS III C grade (P=0.043, and AXL (P=0.001 were still associated with ACV (F=10.252  P<0.001  R2=0.498. Conclusion. With SS-OCT, we found that, in healthy cataract patients, 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.

  9. 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.

    2010-01-01

    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 (RTS

  10. 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

  11. Automated detection of inflammatory cells in whole anterior chamber of a uveitis mouse from swept-source optical coherence tomography images

    Science.gov (United States)

    Choi, Woo June; Pepple, Kathryn L.; Wang, Ruikang K.

    2016-03-01

    Cell grading in a rodent anterior chamber is essential for anterior inflammation evaluation in preclinical vision research. This paper describes a computerized method for detection and counting of the anterior chamber cells from swept-source optical coherence tomography (SS-OCT) images of a experimental rodent model of uveitis. The volumetric anterior segment OCT data is obtained from 100 kHz SS-OCT imaging of mouse eye in vivo. For the OCT cross-sections, each OCT structural image is de-speckled and binarized. After removal of cornea, iris, and crystalline lens structures connected to the binary image border, an area thresholding is then employed for each labeled region to isolate only celllike objects in the anterior chamber, followed by roundness estimation of the objects to identify potential cell candidates in the data. Eventually, the cell candidates are counted and graded as total number of cells in the anterior chamber.

  12. Evaluation of the anterior chamber angle in Asian Indian eyes by ultrasound biomicroscopy and gonioscopy

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    Kaushik Sushmita

    2006-01-01

    Full Text Available Purpose: To compare the ultrasound biomicroscopic measurement of the anterior chamber angle in Asian Indian eyes, with the angle width estimated by gonioscopy. Materials and Methods: Participants: Patients with open and closed angles attending a glaucoma clinic were recruited for the study. Observation Procedures: Temporal quadrants of the angles of patients were categorized by gonioscopy as Grade 0 to Grade 4, using Shaffer′s classification. These angles were quantified by ultrasound biomicroscopy (UBM using the following biometric characteristics: Angle opening distance at 250 µ (AOD 250 and 500 µ (AOD 500 from the scleral spur and trabecular meshwork-ciliary process distance (TCPD. The angles were further segregated as "narrow angles" (Schaffer′s Grade 2 or less and "open angles" (Schaffer′s Grade 3 and 4. Main Outcome Measures: The UBM measurements were computed in each case and analyzed in relation to the gonioscopic angle evaluation. Results: One hundred and sixty three eyes of 163 patients were analyzed. One hundred and six eyes had "narrow angles" and 57 eyes had "open angles" on gonioscopy. There was a significant difference among the mean UBM measurements of each angle grade estimated by gonioscopy ( P < 0.001. The Pearson correlation coefficient between all UBM parameters and gonioscopy grades was significant at the 0.01 level. The mean AOD 250, AOD 500 and TCPD in narrow angles were 58±49 µ, 102±84 µ and 653±124 respectively, while it was 176±47 µ, 291±62 µ and 883±94 µ in eyes with open angles ( P < 0.001 respectively. Conclusions: The angle width estimated by gonioscopy correlated significantly with the angle dimensions measured by UBM. Gonioscopy, though a subjective test, is a reliable method for estimation of the angle width.

  13. Regulation of anterior chamber drainage by bicarbonate-sensitive soluble adenylyl cyclase in the ciliary body.

    Science.gov (United States)

    Lee, Yong S; Tresguerres, Martin; Hess, Kenneth; Marmorstein, Lihua Y; Levin, Lonny R; Buck, Jochen; Marmorstein, Alan D

    2011-12-02

    Glaucoma is a leading cause of blindness affecting as many as 2.2 million Americans. All current glaucoma treatment strategies aim to reduce intraocular pressure (IOP). IOP results from the resistance to drainage of aqueous humor (AH) produced by the ciliary body in a process requiring bicarbonate. Once secreted into the anterior chamber, AH drains from the eye via two pathways: uveoscleral and pressure-dependent or conventional outflow (C(t)). Modulation of "inflow" and "outflow" pathways is thought to occur via distinct, local mechanisms. Mice deficient in the bicarbonate channel bestrophin-2 (Best2), however, exhibit a lower IOP despite an increase in AH production. Best2 is expressed uniquely in nonpigmented ciliary epithelial (NPE) cells providing evidence for a bicarbonate-dependent communicative pathway linking inflow and outflow. Here, we show that bicarbonate-sensitive soluble adenylyl cyclase (sAC) is highly expressed in the ciliary body in NPE cells, but appears to be absent from drainage tissues. Pharmacologic inhibition of sAC in mice causes a significant increase in IOP due to a decrease in C(t) with no effect on inflow. In mice deficient in sAC IOP is elevated, and C(t) is decreased relative to wild-type mice. Pharmacologic inhibition of sAC did not alter IOP or C(t) in sAC-deficient mice. Based on these data we propose that the ciliary body can regulate C(t) and that sAC serves as a critical sensor of bicarbonate in the ciliary body regulating the secretion of substances into the AH that govern outflow facility independent of pressure.

  14. Regulation of Anterior Chamber Drainage by Bicarbonate-sensitive Soluble Adenylyl Cyclase in the Ciliary Body*

    Science.gov (United States)

    Lee, Yong S.; Tresguerres, Martin; Hess, Kenneth; Marmorstein, Lihua Y.; Levin, Lonny R.; Buck, Jochen; Marmorstein, Alan D.

    2011-01-01

    Glaucoma is a leading cause of blindness affecting as many as 2.2 million Americans. All current glaucoma treatment strategies aim to reduce intraocular pressure (IOP). IOP results from the resistance to drainage of aqueous humor (AH) produced by the ciliary body in a process requiring bicarbonate. Once secreted into the anterior chamber, AH drains from the eye via two pathways: uveoscleral and pressure-dependent or conventional outflow (Ct). Modulation of “inflow” and “outflow” pathways is thought to occur via distinct, local mechanisms. Mice deficient in the bicarbonate channel bestrophin-2 (Best2), however, exhibit a lower IOP despite an increase in AH production. Best2 is expressed uniquely in nonpigmented ciliary epithelial (NPE) cells providing evidence for a bicarbonate-dependent communicative pathway linking inflow and outflow. Here, we show that bicarbonate-sensitive soluble adenylyl cyclase (sAC) is highly expressed in the ciliary body in NPE cells, but appears to be absent from drainage tissues. Pharmacologic inhibition of sAC in mice causes a significant increase in IOP due to a decrease in Ct with no effect on inflow. In mice deficient in sAC IOP is elevated, and Ct is decreased relative to wild-type mice. Pharmacologic inhibition of sAC did not alter IOP or Ct in sAC-deficient mice. Based on these data we propose that the ciliary body can regulate Ct and that sAC serves as a critical sensor of bicarbonate in the ciliary body regulating the secretion of substances into the AH that govern outflow facility independent of pressure. PMID:21994938

  15. Predicting combined sewer overflows chamber depth using artificial neural networks with rainfall radar data.

    Science.gov (United States)

    Mounce, S R; Shepherd, W; Sailor, G; Shucksmith, J; Saul, A J

    2014-01-01

    Combined sewer overflows (CSOs) represent a common feature in combined urban drainage systems and are used to discharge excess water to the environment during heavy storms. To better understand the performance of CSOs, the UK water industry has installed a large number of monitoring systems that provide data for these assets. This paper presents research into the prediction of the hydraulic performance of CSOs using artificial neural networks (ANN) as an alternative to hydraulic models. Previous work has explored using an ANN model for the prediction of chamber depth using time series for depth and rain gauge data. Rainfall intensity data that can be provided by rainfall radar devices can be used to improve on this approach. Results are presented using real data from a CSO for a catchment in the North of England, UK. An ANN model trained with the pseudo-inverse rule was shown to be capable of predicting CSO depth with less than 5% error for predictions more than 1 hour ahead for unseen data. Such predictive approaches are important to the future management of combined sewer systems.

  16. Mechanistic modeling of ophthalmic drug delivery to the anterior chamber by eye drops and contact lenses.

    Science.gov (United States)

    Gause, Samuel; Hsu, Kuan-Hui; Shafor, Chancellor; Dixon, Phillip; Powell, Kristin Conrad; Chauhan, Anuj

    2016-07-01

    Ophthalmic drug for the anterior chamber diseases are delivered into tears by either eye drops or by extended release devices placed in the eyes. The instilled drug exits the eye through various routes including tear drainage into the nose through the canaliculi and transport across various ocular membranes. Understanding the mechanisms relevant to each route can be useful in predicting the dependency of ocular bioavailability on various formulation parameters, such as drug concentration, salinity, viscosity, etc. Mathematical modeling has been developed for each of the routes and validated by comparison with experiments. The individual models can be combined into a system model to predict the fraction of the instilled drug that reaches the target. This review summarizes the individual models for the transport of drugs across the cornea and conjunctiva and the canaliculi tear drainage. It also summarizes the combined tear dynamics model that can predict the ocular bioavailability of drugs instilled as eye drops. The predictions from the individual models and the combined model are in good agreement with experimental data. Both experiments and models predict that the corneal bioavailability for drugs delivered through eye drops is less than 5% due to the small area of the cornea in comparison to the conjunctiva, and the rapid clearance of the instilled solution by tear drainage. A contact lens is a natural choice for delivering drugs to the cornea due to the placement of the contact in the immediate vicinity of the cornea. The drug released by the contact towards the cornea surface is trapped in the post lens tear film for extended duration of at least 30min allowing transport of a large portion into the cornea. The model predictions backed by in vivo animal and clinical data show that the bioavailability increases to about 50% with contact lenses. This realization has encouraged considerable research towards delivering ocular drugs by contact lenses. Commercial

  17. EarIy changes of anterior chamber parameters after FS-LASIK%飞秒 LASlK 术后早期前房参数的变化研究

    Institute of Scientific and Technical Information of China (English)

    程蕾; 朱冉; 王丹梅; 魏梅

    2015-01-01

      结论:飞秒LASIK术后早期引起前房参数变化,包括ACD变浅,ACV变小,但对周边前房角无明显影响,对屈光手术后行内眼手术患者有进一步指导作用。%· AlM: To investigate the changes of early anterior chamber parameters after femtosecond laser in -situ keratomileusis ( FS-LASlK) . ·METHODS:A total of 90 patients (90 eyes) in routine operation indications received FS-LASlK operation from January to June 2014 in our hospital were collected, including 47 males (47 eyes) , 43 females (43 eyes) , aged 18-33 years old (mean age 22.38±3.96 years).According to the diopter, the patients were divided into three groups:30 cases ( 30 eyes ) were in mild myopia group (group A) with diopter≤3D;30 cases (30 eyes) were in moderate myopia group ( group B) with diopter >3D and≤6D; 30 cases ( 30 eyes) were in high myopia group (group C) with diopter >6D.Pentacam measurements were used to measure the anterior chamber parameters including the changes of anterior chamber depth ( ACD) , anterior chamber volume ( ACV) , anterior chamber angle ( ACA ) before surgery and at 1, 3mo after surgery respectively. · RESULTS: All surgical procedures were performed successfully without complications. Compared with the value of ACD and ACV at pre-operation and 1, 3mo post-operation among groups A, B, C, there was statistically significant difference ( P0.05).However, in groups A, B and C, the value of ACA had no statistically significant difference ( P>0.05).Diopter had no obvious relevance with the changes of ACD, ACV, ACA values. · CONCLUSlON:The early changes of anterior chamber parameters after FS-LASlK, including that ACD become shallow, ACV become smaller, but there was no obvious effect on the peripheral anterior chamber angle.There will be a further instruction for those people who want to perform intraocular surgery after ocular refractive surgery.

  18. Anterior Chamber Angle Evaluation following Phakic Posterior Chamber Collamer Lens with CentraFLOW and Its Correlation with ICL Vault and Intraocular Pressure

    Science.gov (United States)

    El-Deeb, Mohamed W. A.

    2016-01-01

    Purpose. To assess intraocular pressure (IOP), lens vaulting, and anterior chamber (AC) angle width, following V4C implantable Collamer lens (ICL) procedure for myopic refractive error. Methods. A prospective case series that enrolled 54 eyes of 27 patients that were evaluated before and after V4C phakic posterior chamber Collamer lens implantation for correction of myopic refractive error. Preoperative measurement of IOP was done using Goldmann applanation tonometer and anterior chamber angle width using both Van Herick slit lamp grading system and Scheimpflug tomography imaging (Oculus Pentacam). Follow-up of the aforementioned variables was at 1, 6, and 18 months postoperatively, together with ICL vault measurements. Results. The mean baseline IOP of 11.69 ± 2.15 showed a statistically significant (P = 0.002) increase after 1 month that remained unchanged at 6 and 18 months postoperatively, with mean value of 16.07 ± 4.12, 16.07 ± 4.10, and 16.07 ± 4.13, respectively. Pentacam AC angle width showed a statistically significant decrease at 1 (P = 0.025), 6 (P = 0.016), and 18 (P = 0.010) months postoperatively, with mean preoperative value of 40.14 ± 5.49 that decreased to 25.28 ± 5.33, 25.46 ± 5.44, and 25.49 ± 5.38, at 1, 6, and 18 months, respectively. Mean ICL vault showed moderate correlation with Pentacam AC angle width at 1 (r = −0.435) and 6 (r = −0.424) months. Conclusion. V4C ICL implantation resulted in decrease in AC angle width and increase in IOP, within acceptable physiological values at all time points. PMID:28053776

  19. An analysis of flexible anterior chamber lenses with special reference to the normalized rate of lens explantation.

    Science.gov (United States)

    Lim, E S; Apple, D J; Tsai, J C; Morgan, R C; Wasserman, D; Assia, E I

    1991-02-01

    A survey of 1204 closed-loop anterior chamber intraocular lenses (AC-IOLs) and 310 open-loop AC-IOLs accessioned between November 1982 and January 1990 was conducted at the Center for Intraocular Lens Research. An analysis of complication rates was done after normalization of data with respect to market share totals. The results establish that an unacceptable complication rate is associated with the closed-loop design when compared with either the tripod or quadripod lens styles. Furthermore, the closed-loop designs, while comprising an estimated 45% of the total number of AC-IOLs estimated to be implanted in the United States (n = 674,000), were responsible for 80% of the AC-IOLs explanted after complications and accessioned at the authors' center. A rethinking of the extreme condemnation of all anterior chamber IOLs that has surfaced in recent years is warranted. This is particularly true with respect to indications for use of sutured posterior chamber (PC) IOLs as well as with regard to possible use of open-loop AC-IOLs in less-industrialized nations.

  20. Biometry of anterior segment of human eye on both horizontal and vertical meridians during accommodation imaged with extended scan depth optical coherence tomography.

    Directory of Open Access Journals (Sweden)

    Lin Leng

    Full Text Available To determine the biometry of anterior segment dimensions of the human eye on both horizontal and vertical meridians with extended scan depth optical coherence tomography (OCT during accommodation.Twenty pre-presbyopic volunteers, aged between 24 and 30, were recruited. The ocular anterior segment of each subject was imaged using an extended scan depth OCT under non- and 3.0 diopters (D of accommodative demands on both horizontal and vertical meridians. All the images were analyzed to yield the following parameters: pupil diameter (PD, anterior chamber depth (ACD, anterior and posterior surface curvatures of the crystalline lens (ASC and PSC and the lens thickness (LT. Two consecutive measurements were performed to assess the repeatability and reproducibility of this OCT. They were evaluated by calculating the within-subject standard deviation (SD, a paired t-test, intra-class correlation coefficients (ICC and the coefficient of repeatability/reproducibility (CoR.There were no significant differences between two consecutive measurements on either horizontal or vertical meridians under both two different accommodative statuses (P>0.05. The ICC for all parameters ranged from 0.775 to 0.998, except for the PSC (0.550 on the horizontal meridian under the non-accommodative status. In addition, the CoR for most of the parameters were excellent (0.004% to 4.89%. In all the parameters, only PD and PSC were found different between the horizontal and vertical meridians under both accommodative statuses (P<0.05. PD, ACD, ASC and PSC under accommodative status were significantly smaller than those under the non-accommodative status, except that the PSC at the vertical meridian did not change. In addition, LT was significantly increased when accommodation.The extended scan depth OCT successfully measured the dimensions of the anterior eye during accommodation with good repeatability and reproducibility on both horizontal and vertical meridians. The asymmetry

  1. The Expression of the Plasmid DNA Encoding TGF-β1 in Endothelium after Injection into the Anterior Chamber

    Institute of Scientific and Technical Information of China (English)

    胡燕华; 黄琼; 姜发纲; 陈宏

    2002-01-01

    Summary: The method of gene transfer into corneal endothelium was investigated to provide afoundation for the study of TGF-β1 gene transfer to inhibit corneal graft rejection. Two days afterdirect injection of pMAM TGF-β1 mediated by liposome into the anterior chamber of rabbits, onehalf of corneas were made into paraffin slides and the endothelial layer was carefully torn from theother half to make a single layer slide of endothelia. By means of immunohistochemical technique,the plasmid pMAM TGF-β1 expression product TGF-β1 in the endothelia was detected. SpecificTGF-β1 expression was positive in the endothelia on both the paraffin slide and the single layerslide. The results showed that by direct injection into the anterior chamber, foreign plasmid DNAcould be transferred into the endothelia and its expression was obtained. This may provide a foun-dation for further study on TGF-β1 participating in local induction of corneal immune tolerance.

  2. Effects of confined space and near vision stimulation on refractive status and vitreous chamber depth in adolescent rhesus monkeys

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    This study aimed to investigate the effects of sustained near vision stimulation,on the refractive development and elongation of the vitreous chamber in adolescent rhesus monkeys.A total of 12 adolescent rhesus monkeys(1.5-2.0 years old) were randomly assigned to 3 groups.In groups A(n=4) and B(n=4),monkeys were reared in close-vision cages for 8 and 4 h d-1,respectively;tiny granules were added on the cage floor to avoid visual deprivation and to encourage near gaze.In group C(n=4),monkeys were reared in open-vision cages,with non-granule food as a control.Vitreous chamber depth,refractive status,and corneal refractive power were assessed over 18 months.Paired t-test was used to compare the differences and a P-value<0.05 was considered to be statistically significant.In group A,vitreous chamber depth and optical axis elongated significantly,and refractive error shifted towards myopia during the observation period.In group B,vitreous chambers and optical axis elongated but the refractive power did not show significant changes.In group C,there was no significant elongation in vitreous chambers and optical axis,and the refractive power changed slightly towards hypermetropia.There were no significant changes in corneal refractive power in each group.Sustained near vision can promote vitreous chamber growth and induce myopic shifts in refractive power in adolescent monkeys.Our results demonstrate the potential for a primate model of near-work-related myopia.

  3. Accuracy Evaluation of The Depth of Six Kinds of Sperm Counting Chambers for both Manual and Computer-Aided Semen Analyses

    Directory of Open Access Journals (Sweden)

    Jin-Chun Lu

    2016-12-01

    Full Text Available Background: Although the depth of the counting chamber is an important factor influencing sperm counting, no research has yet been reported on the measurement and comparison of the depth of the chamber. We measured the exact depths of six kinds of sperm counting chambers and evaluated their accuracy. Materials and Methods: In this prospective study, the depths of six kinds of sperm counting chambers for both manual and computer-aided semen analyses, including Makler (n=24, Macro (n=32, Geoffrey (n=34, GoldCyto (n=20, Leja (n=20 and Cell-VU (n=20, were measured with the Filmetrics F20 Spectral Reflectance Thin-Film Measurement System, then the mean depth, the range and the coefficient of variation (CV of each chamber, and the mean depth, relative deviation and acceptability of each kind of chamber were calculated by the closeness to the nominal value. Among the 24 Makler chambers, 5 were new and 19 were used, and the other five kinds were all new chambers. Results: The depths (mean ± SD, μm of Makler (new, Macro and Geoffrey chambers were 11.07 ± 0.41, 10.19 ± 0.48 and 10.00 ± 0.28, respectively, while those of GoldCyto, Leja and Cell-VU chambers were 23.76 ± 2.15, 20.49 ± 0.22 and 24.22 ± 2.58, respectively. The acceptability of Geoffrey chambers was the highest (94.12%, followed by Macro (65.63%, Leja (35% and Makler (20%, while that of the other two kinds and the used Makler chamber was zero. Conclusion: There existed some difference between the actual depth and the corresponding nominal value for sperm counting chambers, and the overall acceptability was very low. Moreover, the abrasion caused by the long use, as of Makler chamber, for example, may result in unacceptability of the chamber. In order to ensure the accuracy and repeatability of sperm concentration results, the depth of the sperm counting chamber must be checked regularly.

  4. 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.

  5. Effects of confined space and near vision stimulation on refractive status and vitreous chamber depth in adolescent rhesus monkeys.

    Science.gov (United States)

    Leng, Yunxia; Lan, Weizhong; Yu, Keming; Liu, Bingqian; Yang, Zhikuan; Li, Zheng; Zhong, Xingwu; Zhang, Shaochong; Ge, Jian

    2010-12-01

    This study aimed to investigate the effects of sustained near vision stimulation, on the refractive development and elongation of the vitreous chamber in adolescent rhesus monkeys. A total of 12 adolescent rhesus monkeys (1.5-2.0 years old) were randomly assigned to 3 groups. In groups A (n=4) and B (n=4), monkeys were reared in close-vision cages for 8 and 4 h d(-1), respectively; tiny granules were added on the cage floor to avoid visual deprivation and to encourage near gaze. In group C (n=4), monkeys were reared in open-vision cages, with non-granule food as a control. Vitreous chamber depth, refractive status, and corneal refractive power were assessed over 18 months. Paired t-test was used to compare the differences and a P-valuemonkeys. Our results demonstrate the potential for a primate model of near-work-related myopia.

  6. COMPARISON OF ANTERIOR CHAMBER REACTION WITH SINGLE-PIECE AND THREE-PIECE INTRAOCULAR LENSES IN MANUAL SMALL INCISION CATARACT SURGERY

    Directory of Open Access Journals (Sweden)

    Usha

    2014-11-01

    Full Text Available OBJECTIVES: To study the anterior chamber reaction between single-piece and three-piece intraocular lenses in manual small incision cataract surgery. METHODS: Prospective study done at Mysore Race Club Charitable Eye Hospital. 140 Patients underwent suture less sclerocorneal tunnel cataract surgeries with single-piece or three-piece Polymethylmethacrylate (PMMA intra ocular lenses (3-piece IOL. Accurate Keratometry was done with the help of Bausch and Lomb Keratometer. IOL power was calculated by using SRK (Sanders-Retzlaff-Kraff II formula, with the help of non-immersion, contact type of A-Scan biometry. Single-piece IOLs were inserted in 70 patients. Three-piece IOL inserted in rest of 70 patients. Slit lamp examination for anterior chamber cells was graded according to Hogan system. Aqueous cells were measured by counting within the visible field under Slit lamp, keeping the beam at maximum intensity. Anterior chamber reaction (AC in 1stPostoperative week and at 8 weeks are compared and analyzed by ANOVA statistics. RESULTS: Single piece IOL group had anterior chamber reaction ranging from 1 to 2+ cells i.e., in 97%. In three-piece IOL group, 70%of eyes had 2+ cells and 12.8% had 3± cells. At 8 weeks, single- piece IOL showed either no cells or occasional cells in 98.6% of patients, compared to three –piece IOL group showing in 77%of cases. 23% had 1+ cells in later group. CONCLUSION: Single-piece implanted IOLs had significant less number of cells were seen in anterior chamber from 1 week to 8 weeks as compared to three-piece IOLs.

  7. Depth

    NARCIS (Netherlands)

    Koenderink, J.J.; Van Doorn, A.J.; Wagemans, J.

    2011-01-01

    Depth is the feeling of remoteness, or separateness, that accompanies awareness in human modalities like vision and audition. In specific cases depths can be graded on an ordinal scale, or even measured quantitatively on an interval scale. In the case of pictorial vision this is complicated by the f

  8. Anterior Lamina Cribrosa Surface Depth in Open-Angle Glaucoma: Relationship with the Position of the Central Retinal Vessel Trunk.

    Directory of Open Access Journals (Sweden)

    Baek-Lok Oh

    Full Text Available To determine the factors influencing the anterior lamina cribrosa (LC surface depth (LCD in patients with open-angle glaucoma (OAG, focusing on the association between LCD and the position of the central retinal vessel trunk (CRVT at the anterior LC surface.Optic nerve heads of 205 OAG eyes were scanned using swept-source optical coherence tomography (SS-OCT. After processing the images using adaptive compensation, the LCD was determined from 11 horizontal B-scan images that divided the optic disc vertically into 12 equal parts. Eyes were divided into two groups (central or peripheral according to where the CRVT exits from the anterior LC surface. The influence of CRVT position on LCD was evaluated, taking into account age, gender, untreated intraocular pressure (IOP, IOP at optic-disc scanning, retinal nerve fiber layer (RNFL thickness, visual-field mean deviation, central corneal thickness, and axial length.Patients in the peripheral CRVT group were younger and more myopic, and had a larger mean LCD and thinner global RNFL than those in the central CRVT group (all P≤0.023. On multivariate analysis, the peripheral CRVT location was significantly associated with a larger LCD (P = 0.002, together with the significant association of younger age (P<0.001, higher untreated IOP (P = 0.010, and thinner RNFL (P = 0.003 on the larger LCD.In OAG, CRVT location was an independent factor influencing the LCD, together with age, untreated IOP, and global RNFL thickness. The data indicate that the CRVT may contribute to the resistance of the LC against deformation. A longitudinal prospective observation is required to clarify this relationship.

  9. SU-E-T-561: Development of Depth Dose Measurement Technique Using the Multilayer Ionization Chamber for Spot Scanning Method

    Energy Technology Data Exchange (ETDEWEB)

    Takayanagi, T; Fujitaka, S; Umezawa, M [Hitachi, Ltd., Hitachi Research Laboratory, Hitachi-shi, Ibaraki-ken (Japan); Ito, Y; Nakashima, C; Matsuda, K [Hitachi, Ltd., Hitachi Works, Hitachi-shi, Ibaraki-ken (Japan)

    2014-06-01

    Purpose: To develop a measurement technique which suppresses the difference between profiles obtained with a multilayer ionization chamber (MLIC) and with a water phantom. Methods: The developed technique multiplies the raw MLIC data by a correction factor that depends on the initial beam range and water equivalent depth. The correction factor is derived based on a Bragg curve calculation formula considering range straggling and fluence loss caused by nuclear reactions. Furthermore, the correction factor is adjusted based on several integrated depth doses measured with a water phantom and the MLIC. The measured depth dose profiles along the central axis of the proton field with a nominal field size of 10 by 10 cm were compared between the MLIC using the new technique and the water phantom. The spread out Bragg peak was 20 cm for fields with a range of 30.6 cm and 6.9 cm. Raw MLIC data were obtained with each energy layer, and integrated after multiplying by the correction factor. The measurements were performed by a spot scanning nozzle at Nagoya Proton Therapy Center, Japan. Results: The profile measured with the MLIC using the new technique is consistent with that of the water phantom. Moreover, 97% of the points passed the 1% dose /1mm distance agreement criterion of the gamma index. Conclusion: We have demonstrated that the new technique suppresses the difference between profiles obtained with the MLIC and with the water phantom. It was concluded that this technique is useful for depth dose measurement in proton spot scanning method.

  10. 窄房角合并虹膜睫状体囊肿的解剖因素分析%Analysis of anatomy features for patients with narrow anterior chamber angle and primary iridociliary body cysts

    Institute of Scientific and Technical Information of China (English)

    李贵刚; 纪彩霓; 李新宇; 胡维琨; 胡军; 王军明; 李涛; 李斌; 张虹

    2012-01-01

    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.Results 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 eases 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° ).Conclusions 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.

  11. 有晶状体眼后房型人工晶状体植入术后前房及前房角的超声活体显微镜观察%Observation on changes of anterior chamber and chamber angle structures after posterior chamber phakic intraocular lens implantation by ultrasound biomicroscopy

    Institute of Scientific and Technical Information of China (English)

    汪晓宇; 沈晔; 杜持新; 李毓敏; 董映

    2009-01-01

    Objective To study the changes of anterior chamber and chamber angle structures after implantable contact lens (ICL) implantation in high myopia by using ultrasound biomicroscopy (UBM).Methods A prospective series case study was conducted on 15 high myopia patients (30 eyes) treated with ICL implant.These patients were followed for one year postoperatively.Intraocular pressure (IOP) was measured by Goldmann applanation tonometer after surgery.All eyes were examined by UBM one year after the surgery.Central anterior chamber depth (ACD), trabecular-iris angle (TIA), the distance between the posterior surface of ICL and the lens and the distance between peripheral surface of ICL and the lens were measured.Nonparametric test was used to compare TIA.One-way ANOVA was used to assess the distance between peripheral surface of ICL and the lens.Repeated Measure ANOVA and Bonferroni test was performed to compare the IOP level before and after surgery.Paired t-test was used to compare ACD.Results Intraocular pressure changed from (13.75±2.27) mm Hg(1 mm Hg=0.133 kPa) preoperatively to (14.27±1.70), (14.70±2.07), (14.07±2.24), (14.00±2.69) and (13.97±2.95) mm Hg at 1 week, 1,3, 6 and 12 months after the surgery, respectively.There was a statistically significant increase of the IOP one month after the surgery, which was normalized completely at 3 months after surgery.The distances between central posterior surface of the cornea to the ICL and the lens were (2.24±0.21 ) and (2.97±0.11) mm, respectively.There was significant difference between these two data (t=20.63, P30°,ICL周边部与晶状体之间的距离在钟表位12:00、3:00、6:00、9:00位差异无统计学意义.ICL后表面与晶状体之间的距离为(0.63±0.16)mm,ICL与晶状体无接触.结论 ICL植入术后ICL位于晶状体前,致使术后中央ACD变浅、部分手术眼前房角宽度变窄.ICL与晶状体无接触,与虹膜后表面接触.

  12. Allegro Oculyzer 眼前节诊断系统评估 ICL 术后眼前节参数变化与眼压相关性分析%Assessment on changes of anterior chamber parameters after ICL surgery with Allegro Oculyzer system and their correlation with IOP

    Institute of Scientific and Technical Information of China (English)

    陈庆; 余鹏; 赵雅丽; 郭晓枚

    2016-01-01

    Abstract? AIM: To investigate changes of anterior chamber parameters after posterior chamber phakic implantable collamer lens ( ICL ) surgery and its correlation with intraocular pressure ( IOP) .?METHODS: This was a retrospective case series study. Seventy four eyes in 43 myopia patients were examined by Allegro Oculyzer anterior segment tomography to obtain the changes of anterior chamber volume ( ACV ) , anterior chamber angle ( ACA) , central anterior chamber depth ( ACD) and vault, meanwhile, to measure the IOP to analyze the correlation with anterior chamber parameters.?RESULTS: Compared with preoperative, ACV, ACA, ACD all decreased apparently ( P 0.05).?CONCLUSION:For patients underwent ICL, the anterior chamber parameters all decreased which included ACV, ACA, ACD, and had stabilized since early postoperative period. Correspondingly, IOP was stable and had not correlate with ACV, ACA, ACD and vault, however the long-term observation is still necessary.%目的:研究有晶状体眼后房型人工晶状体植入术( posterior chamber phakic implantable collamer lens surgery ,ICL)后眼前节参数变化及各参数与眼内压( intraocular pressure , IOP)间相关性。方法:回顾性研究。2012/2014年于苏州理想眼科医院屈光手术中心行ICL患者43例74眼,应用Allegro Oculyzer眼前节诊断系统测量其术前、术后1、3、6 mo 前房容积( anterior chamber volume , ACV )、房角( anterior chamber angle,ACA )、中央前房深度( central anterior chamber depth,ACD)、拱高( vault)变化,并测量同一时期眼内压后进行统计学分析。结果:术前与术后1、3、6mo相比,术后较术前ACV,ACA, ACD均较显著减小(P<0.01)。术后ACV,ACA,ACD在各随访观测时间点均稳定,术后vault 在1mo与6mo间存在统计学差异( t=27.66, P=0.01)。而IOP术前与术后各测量点间无统计学差异( P>0.05)。各时期 IOP 与ACV

  13. SU-E-T-562: Scanned Percent Depth Dose Curve Discrepancy for Photon Beams with Physical Wedge in Place (Varian IX) Using Different Sensitive Volume Ion Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, H; Sarkar, V; Rassiah-Szegedi, P; Huang, Y; Szegedi, M; Huang, L; Salter, B [University Utah, Salt Lake City, UT (United States)

    2014-06-01

    Purpose: To investigate and report the discrepancy of scanned percent depth dose (PDD) for photon beams with physical wedge in place when using ion chambers with different sensitive volumes. Methods/Materials: PDD curves of open fields and physical wedged fields (15, 30, 45, and 60 degree wedge) were scanned for photon beams (6MV and 10MV, Varian iX) with field size of 5x5 and 10x10 cm using three common scanning chambers with different sensitive volumes - PTW30013 (0.6cm3), PTW23323 (0.1cm3) and Exradin A16 (0.007cm3). The scanning system software used was OmniPro version 6.2, and the scanning water tank was the Scanditronix Wellhoffer RFA 300.The PDD curves from the three chambers were compared. Results: Scanned PDD curves of the same energy beams for open fields were almost identical between three chambers, but the wedged fields showed non-trivial differences. The largest differences were observed between chamber PTW30013 and Exradin A16. The differences increased as physical wedge angle increased. The differences also increased with depth, and were more pronounced for 6MV beam. Similar patterns were shown for both 5x5 and 10x10 cm field sizes. For open fields, all PDD values agreed with each other within 1% at 10cm depth and within 1.62% at 20 cm depth. For wedged fields, the difference of PDD values between PTW30013 and A16 reached 4.09% at 10cm depth, and 5.97% at 20 cm depth for 6MV with 60 degree physical wedge. Conclusion: We observed a significant difference in scanned PDD curves of photon beams with physical wedge in place obtained when using different sensitive volume ion chambers. The PDD curves scanned with the smallest sensitive volume ion chamber showed significant difference from larger chamber results, beyond 10cm depth. We believe this to be caused by varying response to beam hardening by the wedges.

  14. 通过前房相关免疫偏离阻止实验性自身免疫前葡萄膜炎%Prevention of experimental autoimmune anterior uveitis by anterior chamber-associated immune deviation

    Institute of Scientific and Technical Information of China (English)

    李志杰; 彭广华; 冯铮; 李辰

    1999-01-01

    Objective Experimental autoimmune anterior uveitis (EAAU) is a useful model for human anterior uveitis. The purpose of this study was to observe whether EAAU development could be prevented by anterior chamber-associated immune deviation (ACAID). Methods Bovine melanin protein (BMP) in phosphate-buffered saline (PBS) was injected into the anterior chamber of the right eye of rats; control animals were injected with PBS alone. Seven days later, all animals were immunized with BMP in complete Freund's adjuvant (CFA) and pertussis toxin. The severity and incidence of uveitis was monitored by clinical examination and histopathology. The delayed-type hypersensitivity (DTH) responses were evaluated by footpad swelling elicited by injection of BMP.Results Rats intraocularly injected with BMP showed a reduced severity and incidence of EAAU, and significantly suppressed DTH response compared to control rats.Conclusion These data suggest that the ACAID procedure can be utilized to prevent the development of EAAU.%目的实验性自身免疫性前葡萄膜炎(EAAU)是研究人前葡萄膜炎的有用模型.本研究旨在观察前房相关免疫偏离(ACAID)能否阻止EAAU发生.方法将溶于磷酸盐缓冲液(PBS)的牛黑色素蛋白(BMP)注射于大鼠右眼前房;对照组动物仅注射PBS.7d后,使用添加完全福氏佐剂(CFA)的BMP和百日咳毒素免疫所有动物.通过临床观察和组织病理学检测葡萄膜炎的严重程度和发病率.通过由注射BMP刺激的足垫水肿反应评估迟发型超敏反应(DTH).结果与对照组相比,预先眼内注射BMP的大鼠,其EAAU的严重程度和发病率减低,且DTH反应受到显著抑制.结论这些资料提示ACAID可以用来阻止EAAU的发生.

  15. Disappearance of anterior chamber with high intraocular pressure in phacoemulsification%超声乳化术中前房消失伴高眼压

    Institute of Scientific and Technical Information of China (English)

    傅波; 苗春旭; 冯万国; 宫冰冰; 肖梦媛

    2013-01-01

    目的 研究白内障超声乳化术中前房突然消失伴眼压升高的原因、处理及预防.方法 单纯性老年性白内障行超声乳化过程中,67例(67眼)突发前房消失、高眼压,其中4例暂停手术,快速静脉滴注20%甘露醇250 ml,1h后眼压降低,黏弹剂重建前房,顺利完成手术.3例于睫状体平坦部进针吸出玻璃体内0.1ml液体,顺利重建前房.其余60例(60眼)前房频注黏弹剂,勉强完成手术,出现并发症.结果 切口处虹膜反复脱出43例,相应部位虹膜萎缩脱色素,瞳孔不圆.后囊较小破裂3例,人工晶状体照常植入囊袋内.后囊明显破裂2例,玻璃体脱出,施行前段玻璃体切除,人工晶体睫状沟植入,缝线悬吊.术中后弹力层部分脱离6例,用空气泡复位.58例不同程度角膜内皮水肿,于术后3~5d恢复.结论 白内障超声乳化术中前房突然消失、眼压升高,导致失去器械活动空间,手术风险增大,并发症相对增加.此情况的出现部分为解剖因素,但不乏与操作有关,应予以高度重视并采取有效措施,可转危为安.%Objective To study the reasons,treatment and prevention of anterior chamber disappearance with high intraocular pressure during cataract phacoemulsification.Methods Of simply age-related cataract in our hospital' s Ophthamology Dept.,67 cases (67 eyes) of anterior chamber disappearance with high intraocular pressure happened in phacoemulsification.Operation process suspended for 4 cases,immediately intravenous injection of 20% mannital 250 ml.Intraocular pressure lowered 1 hour later.Reconstruct anterior chamber with viscoelastic agent to complete operation safely.For 3 cases,insert needle through pars plana of ciliary body sucking 0.1 ml liquid from vitreous.Reconstruct anterior chamber smoothly.For the remaining 60 cases (60 eyes),repeatedly inject viscoelastic agent into anterior chamber.Operation finished difficultly,complication appeared.Results Iris prolapsed from

  16. Development of Extended-Depth Swept Source Optical Coherence Tomography for Applications in Ophthalmic Imaging of the Anterior and Posterior Eye

    Science.gov (United States)

    Dhalla, Al-Hafeez Zahir

    Optical coherence tomography (OCT) is a non-invasive optical imaging modality that provides micron-scale resolution of tissue micro-structure over depth ranges of several millimeters. This imaging technique has had a profound effect on the field of ophthalmology, wherein it has become the standard of care for the diagnosis of many retinal pathologies. Applications of OCT in the anterior eye, as well as for imaging of coronary arteries and the gastro-intestinal tract, have also shown promise, but have not yet achieved widespread clinical use. The usable imaging depth of OCT systems is most often limited by one of three factors: optical attenuation, inherent imaging range, or depth-of-focus. The first of these, optical attenuation, stems from the limitation that OCT only detects singly-scattered light. Thus, beyond a certain penetration depth into turbid media, essentially all of the incident light will have been multiply scattered, and can no longer be used for OCT imaging. For many applications (especially retinal imaging), optical attenuation is the most restrictive of the three imaging depth limitations. However, for some applications, especially anterior segment, cardiovascular (catheter-based) and GI (endoscopic) imaging, the usable imaging depth is often not limited by optical attenuation, but rather by the inherent imaging depth of the OCT systems. This inherent imaging depth, which is specific to only Fourier Domain OCT, arises due to two factors: sensitivity fall-off and the complex conjugate ambiguity. Finally, due to the trade-off between lateral resolution and axial depth-of-focus inherent in diffractive optical systems, additional depth limitations sometimes arises in either high lateral resolution or extended depth OCT imaging systems. The depth-of-focus limitation is most apparent in applications such as adaptive optics (AO-) OCT imaging of the retina, and extended depth imaging of the ocular anterior segment. In this dissertation, techniques for

  17. Comparison of depth-dose distributions of proton therapeutic beams calculated by means of logical detectors and ionization chamber modeled in Monte Carlo codes

    Science.gov (United States)

    Pietrzak, Robert; Konefał, Adam; Sokół, Maria; Orlef, Andrzej

    2016-08-01

    The success of proton therapy depends strongly on the precision of treatment planning. Dose distribution in biological tissue may be obtained from Monte Carlo simulations using various scientific codes making it possible to perform very accurate calculations. However, there are many factors affecting the accuracy of modeling. One of them is a structure of objects called bins registering a dose. In this work the influence of bin structure on the dose distributions was examined. The MCNPX code calculations of Bragg curve for the 60 MeV proton beam were done in two ways: using simple logical detectors being the volumes determined in water, and using a precise model of ionization chamber used in clinical dosimetry. The results of the simulations were verified experimentally in the water phantom with Marcus ionization chamber. The average local dose difference between the measured relative doses in the water phantom and those calculated by means of the logical detectors was 1.4% at first 25 mm, whereas in the full depth range this difference was 1.6% for the maximum uncertainty in the calculations less than 2.4% and for the maximum measuring error of 1%. In case of the relative doses calculated with the use of the ionization chamber model this average difference was somewhat greater, being 2.3% at depths up to 25 mm and 2.4% in the full range of depths for the maximum uncertainty in the calculations of 3%. In the dose calculations the ionization chamber model does not offer any additional advantages over the logical detectors. The results provided by both models are similar and in good agreement with the measurements, however, the logical detector approach is a more time-effective method.

  18. Variable temperature effects of Open Top Chambers at polar and alpine sites explained by irradiance and snow depth

    NARCIS (Netherlands)

    Bokhorst, S.; Huiskes, A.; Aerts, R.; Convey, P.; Cooper, E.J.; Dalen, L.; Erschbamer, B.; Gudmundsson, J.; Hofgaard, H.; Hollister, R.D.; Johnstone, J.; Jónsdóttir, I.S.; Lebouvier, M.; Van de Vijver, B.; Wahren, C.-H.; Dorrepaal, E.

    2013-01-01

    Environmental manipulation studies are integral to determining biological consequences of climate warming. Open Top Chambers (OTCs) have been widely used to assess summer warming effects on terrestrial biota, with their effects during other seasons normally being given less attention even though cha

  19. Comparison of depth-dose distributions of proton therapeutic beams calculated by means of logical detectors and ionization chamber modeled in Monte Carlo codes

    Energy Technology Data Exchange (ETDEWEB)

    Pietrzak, Robert [Department of Nuclear Physics and Its Applications, Institute of Physics, University of Silesia, Katowice (Poland); Konefał, Adam, E-mail: adam.konefal@us.edu.pl [Department of Nuclear Physics and Its Applications, Institute of Physics, University of Silesia, Katowice (Poland); Sokół, Maria; Orlef, Andrzej [Department of Medical Physics, Maria Sklodowska-Curie Memorial Cancer Center, Institute of Oncology, Gliwice (Poland)

    2016-08-01

    The success of proton therapy depends strongly on the precision of treatment planning. Dose distribution in biological tissue may be obtained from Monte Carlo simulations using various scientific codes making it possible to perform very accurate calculations. However, there are many factors affecting the accuracy of modeling. One of them is a structure of objects called bins registering a dose. In this work the influence of bin structure on the dose distributions was examined. The MCNPX code calculations of Bragg curve for the 60 MeV proton beam were done in two ways: using simple logical detectors being the volumes determined in water, and using a precise model of ionization chamber used in clinical dosimetry. The results of the simulations were verified experimentally in the water phantom with Marcus ionization chamber. The average local dose difference between the measured relative doses in the water phantom and those calculated by means of the logical detectors was 1.4% at first 25 mm, whereas in the full depth range this difference was 1.6% for the maximum uncertainty in the calculations less than 2.4% and for the maximum measuring error of 1%. In case of the relative doses calculated with the use of the ionization chamber model this average difference was somewhat greater, being 2.3% at depths up to 25 mm and 2.4% in the full range of depths for the maximum uncertainty in the calculations of 3%. In the dose calculations the ionization chamber model does not offer any additional advantages over the logical detectors. The results provided by both models are similar and in good agreement with the measurements, however, the logical detector approach is a more time-effective method. - Highlights: • Influence of the bin structure on the proton dose distributions was examined for the MC simulations. • The considered relative proton dose distributions in water correspond to the clinical application. • MC simulations performed with the logical detectors and the

  20. Early Diagnosis of Keratoconus with Orbscan- Ⅱ Anterior System

    Institute of Scientific and Technical Information of China (English)

    李新宇; 刘磊; 邱良秀

    2002-01-01

    Summary: Orbscan- Ⅱ anterior system was used for early diagnosis of keratoconus. 48 Eyes of 24patients with suspicious keratoconus were examined by Orbscan-Ⅱ anterior system from Dec.1999 to Dec. 2000 and followed up. The values of Diff and anterior chamber depth (ACD) wererecorded. Results indicated that values of Diff and ACD were increased in 4 eyes of 2 patients withkeratoconus trend during follow-up. Taking advantage of Orbscan- Ⅱ anterior system to observethe values of Diff and ACD can early diagnose the sub-clinical keratoconus. The values of Diff andACD can sensitively report the progression of keratoconus.

  1. 人工晶状体植入术后房角与眼压变化之间的相关性研究%Correlation of the anterior chamber angle and intraocular pressure changes after intraocular lens implantation

    Institute of Scientific and Technical Information of China (English)

    刘玉青; 叶存喜; 刘玉霞; 戴冬姝; 冀向宁; 王静娴; 邹媛媛; 李坤; 王志学; 侯四清

    2011-01-01

    of UBM ,angle parameters : AOD500 , TIA, ACD, and the Goldmann tonometer IOP were reviewed. 2 weeks, 1 month, 3 months after surgery , UBM , Goldmann tonometer, and all above parameters were re-analyzed. Preoperative and 1 - month postoperative gonioscopy were observed. Results There was a significant difference of intraocular pressure , anterior chamber depth,angle opening distance, trabecular iris angle, intraocular pressure hetween preoperative and postoperative measurements at 2 weeks, 1 month and 3 month ( P<0.05 ). The angle opening distance and intraocular pressure was negatively correlated, trabecular iris angle and intraocular pressure changes was negatively correlated. Conclusion ( 1 )There is no no significant difference of anterior chamber depth, angle opening distance, trabecular iris angle of the anterior segment associated ; However, the intraocular pressure is higher than normal, suggesting that some patients with angle-closure has a potential to develop glaucoma. ( 2 )After phacoemulsification cataract extraction with intraocular lens implantation, anterior chamher depth and angle width is significantly increased, intraocular pressure is decreased significantly, to avoid or reduce the incidence of angle-closure glaucoma. 3. angle opening distance and trahecular iris angle are negatively correlated with intraocular pressure, demonstrated that in the elderly population, the angle opening distance, trabecular iris angle are important factors affecting the intraocular pressure.

  2. Visualization of the ocular pulse in the anterior chamber of the mouse eye in vivo using phase-sensitive optical coherence tomography

    Science.gov (United States)

    Li, Peng; Ding, Zhihua; Ni, Yang; Xu, Baishen; Zhao, Chen; Shen, Yi; Du, Chixin; Jiang, Bo

    2014-09-01

    We report on a phase-based method for accurately measuring the ocular pulse in the anterior chamber in vivo. Using phase-sensitive optical coherence tomography with optimized scanning protocols and equations for compensating bulk motion and environmental vibrations, a high sensitivity of 0.9 μm/s minimal velocity is demonstrated at a wide detection band of 0 to 380 Hz. The pulsatile relative motion between cornea and crystalline lens in rodents is visualized and quantified. The relative motion is most likely caused by respiration (1.6 Hz) and heartbeat (6.6 Hz). The velocity amplitude of the relative motion is 10.3±2.4 μm/s. The displacement amplitudes at the respiratory and cardiac frequencies are 202.5±64.9 and 179.9±49.4 nm, respectively. The potential applications of the measurement technique can be found in the evaluation of intraocular pressure and the measurement of biomechanical properties of the ocular tissue, which are important in several ocular diseases.

  3. Comparison of different techniques of cataract surgery in bacterial contamination of the anterior chamber in diabetic and non-diabetic population

    Directory of Open Access Journals (Sweden)

    M Ashok Kumar

    2012-01-01

    Full Text Available Aim : To compare the bacterial contamination of the anterior chamber (AC between manual small incision cataract surgery (SICS and phacoemulsification (Phaco. To study the conjunctival flora and bacterial contamination of AC between well-controlled diabetics and non-diabetics. Materials and Methods : Three hundred and sixty-eight patients were randomized to manual SICS and Phaco. Sixty-eight patients were excluded for not completing follow-up or for intraoperative complications like posterior capsule rupture. One hundred and fifty patients in each group were finally analyzed. Conjunctival swabs were taken on admission, after one day of topical ofloxacin and 15 min after 5% Povidone Iodine (PI instillation. AC aspirate at the end of the surgery was also cultured. Results : Fifty-six (18.66% patients had positive conjunctival swab on admission which was reduced to 19 (6.33% with topical ofloxacin and to five (1.66% with instillation of 5% PI. AC contamination in both manual SICS and Phaco was 0.66%. The conjunctival flora in diabetics was similar to non-diabetics. None of the diabetics had AC contamination. Statistical analysis was performed by Chi-Square test (with Yates′ correction. Conclusion : Statistically significant reduction in conjunctival flora was achieved with topical ofloxacin and 5% PI instillation and AC contamination in both manual SICS and Phaco was minimal (0.66%. Well-controlled diabetics who underwent cataract surgery in this study had similar conjunctival flora and AC contamination as non-diabetics.

  4. 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

  5. The in vivo and in vitro induction of anterior chamber associated immune deviation to myelin antigens in C57BL/6 mice.

    Science.gov (United States)

    Farooq, Shukkur M; Elkhatib, Walid F; Ashour, Hossam M

    2014-11-01

    Introduction of antigens into the anterior chamber (AC) of the eye generates a specific systemic form of tolerance that is termed AC-associated immune deviation (ACAID). Experimental autoimmune encephalomyelitis (EAE) is an animal model of the human CNS demyelinating diseases, including multiple sclerosis (MS) and acute disseminated encephalomyelitis. We investigated whether the encephalitogenic antigens myelin oligodendrocyte glycoprotein (MOG35-55) or myelin basic protein (MBP) induce ACAID in the EAE-prone C57BL/6 mice. We hypothesized that injection of MOG35-55/MBP induces antigen-specific tolerance whether via the AC route, the adoptive transfer of in vitro-generated MOG35-55-specific/MBP-specific ACAID antigen presenting cells (APCs), or the adoptive transfer of MOG35-55-specific/MBP-specific ACAID T regulatory cells (Tregs). ACAID is characterized by the specific impairment of delayed-type hypersensitivity (DTH) responses. Thus, DTH assays were used to test for ACAID following the AC injection of MOG35-55/MBP, or the intravenous injection of MOG35-55-specific/MBP-specific ACAID APCs. The functional local adoptive transfer (LAT) assays were used to examine the putative regulatory functions of in vitro generated MOG35-55-specific/MBP-specific Tregs. This report is the first to demonstrate the in vivo and in vitro induction of MOG35-55-specific/MBP-specific ACAID-mediated tolerance in C57BL/6 mice. These findings highlight the need for novel immunotherapeutic strategies for MS and optic neuritis.

  6. 前房穿刺治疗急性闭角型青光眼的临床观察%Clinical observation of anterior chamber puncture in the treatment of acute angle closure glaucoma

    Institute of Scientific and Technical Information of China (English)

    陈秀华

    2015-01-01

    Objective:To explore the clinical effect of anterior chamber puncture in the treatment of acute angle closure glaucoma. Methods:30 patients with acute angle closure glaucoma(33 eyes) were selected.They were given anterior chamber puncture treatment.The curative effects of patients were observed.Results:The intraocular pressure and vision of patients after treatment were significantly better than those before treatment(P<0.05).Conclusion:The curative effect of anterior chamber puncture in the treatment acute angle closure glaucoma is significant.%目的:探讨前房穿刺治疗急性闭角型青光眼的临床效果。方法:收治急性闭角型青光眼患者30例(33眼),给予前房穿刺术治疗,观察患者的疗效。结果:治疗后患者眼压和视力明显优于治疗前(P<0.05)。结论:前房穿刺术治疗急性闭角型青光眼疗效显著。

  7. 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

    Directory of Open Access Journals (Sweden)

    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

  8. 类风湿关节炎患者人工晶状体植入后前房反应%Anterior chamber inflammation after intraocular lens implantation in patients with rheumatoid arthritis

    Institute of Scientific and Technical Information of China (English)

    马伟华; 赵俊丽

    2013-01-01

    目的 观察类风湿关节炎患者白内障囊外摘出人工晶状体植入术(ECCE+ IOL)与超声乳化吸出人工晶状体植入术(Phaco+ IOL),比较其术后前房反应程度;探讨类风湿因子滴度与术后前房反应的关系.方法 类风湿关节炎患者11例(11眼)行ECCE+ IOL术;10例(12眼)行Phaco+ IOL术.术后复诊随访.结果 除1例(1眼)视神经萎缩,1例(1眼)老年黄斑变性外,其它均获得了0.6或以上的矫正视力,3个月后前房炎症消失,无手术并发症;行Phaco+ IOL术后前房反应较ECCE +IOL术后前房反应轻,术后3d两组间的差异具有统计学意义(mann-whitney u test分析P=0.0258).术后3d、1个月不同前房反应组的类风湿因子之间差异无统计学意义(mann-whitney utest分析,P>0.05).结论 类风湿性关节炎患者Phaco+ IOL术后前房反应较ECCE +IOL术后前房反应轻;术后前房反应的程度与术前类风湿因子滴度无关.%Objective To compare the postoperative anterior chamber inflammation between extracapsular cataract extraction with intraocular lens implantation (ECCE + IOL) and phacoemulsification with intraocular lens implantation (Phaco + IOL) on patients with rheumatoid arthritis,and to investigate the relation of rheumatoid factor and inflammation in anterior chamber.Methods The medical records of 23 eyes of 21patients with rheumatoid arthritis were reviewed,who underwent cataract extraction with intraocular lens implantation.ECCE + IOL was performed in 11 cases (11 eyes),and Phaco + IOL was performed in 10 cases (12 eyes).Patients had been followed up for 3 months.Results All the eyes,except for one case of optic atrophy and one case of age-related macular degeneration,acquired visual acuity of 0.6 or better.Inflammation in anterior chamber disappeared 3 months after surgery,and left no operative complication in any of the eyes.The inflammation in anterior chamber on patients who performed Phaco + IOL was lighter than patients who performed

  9. Surveying of Pressure in Posterior Chamber and Pressure Difference Between Anterior and Posterior Chambers of Rabbit Eye in Vivo%正常兔眼后房压强及前后房压强差值的在体监测

    Institute of Scientific and Technical Information of China (English)

    宋红芳; 杨红玉; 刘志成

    2011-01-01

    目的 寻求一种眼后房穿刺方法,并在体测量兔眼的前、后房压强差.方法 利用高精度压力传感器与空气差压传感器,采用"从角巩膜缘外周1~1.5mm处进针穿透巩膜,使针水平滑行于虹膜下而进入后房"的扎针方法,实现在体连续监测正常兔眼麻醉状态下的后房压强与前后房压强差值.结果 麻醉状态下兔眼后房压强的范围在839.93~2662.48Pa;前、后房压强差范围是46.15~85.52Pa,均值为59.73Pa,变化周期为11.17min.结论 扎针方法测量兔眼后房压强及前后房压强差值对眼球损伤较小,监测到的正常兔眼后房压强及前后房压强差值均在合理可信的范围内.监测方法的可行性为青光眼前后房压强差值的在体监测提供了新的思路.%Objective To find a proper method of puncturing into the posterior chamber of the rabbit eye and to measure the pressure in posterior chamber and the pressure difference between anterior and posterior chambers in vivo. Methods With the help of the high-accuracy pressure and pressure difference sensors, the pressure in posterior chamber and the pressure difference between anterior and posterior chambers were measured continuously in normal rabbit eyes with anesthesia in vivo. The needle directly punctured into the posterior chamber at 1 to 1.5 millimeters away from the cornea-sclera limbus, penetrated the sclera, and then slided horizontally the needle underneath the iris. Results The pressure value in posterior chamber was from 839. 93 Pa to 2662. 48 Pa, while the pressure difference between anterior and posterior chambers was from 46. 15 Pa to 85. 52 Pa with its average value 59. 73 Pa and the wave period was about 11. 17 min. Conclusions The puncture method for surveying the pressure of rabbit ' s chambers does less hurt to the eye-ball and the experimental data of the pressures in posterior chamber and pressure difference between anterior and posterior chambers. are authentic and

  10. The effects of depth-dependent crustal viscosity variation on visco-elastic response to inflation/deflation of magma chamber

    Science.gov (United States)

    Yamasaki, Tadashi

    2016-04-01

    Development of the satellite observations (GPS and/or InSAR) has allowed us to precisely measure surface deformation. However any geodetic observation by itself does not tell us a mechanism of the deformation. All we can do the most is to compare such an observation to some quantitative predictions, only from which we can deduce a possible deformation mechanism. We therefore need to understand characteristic deformation pattern for a given source mechanism. This study particularly pays attention to magmatic activity in depth as the source, aiming to distinguish magma-induced crustal deformation by better knowing how the activity can be reflected in geodetically observable surface deformation. A parallelized 3-D finite element code, OREGANO_VE [e.g., Yamasaki and Houseman, 2015, J. Geodyn., 88, 80-89], is used to solve the linear Maxwell visco-elastic response to an applied internal inflation/deflation of magma chamber. The rectangular finite element model is composed with a visco-elastic layer overlaid by an elastic layer with thickness of H, and the visco-elastic layer extends over the rest of crust and the uppermost mantle. The visco-elastic crust has a depth-dependent viscosity (DDV) as an exponential function of depth due to temperature-dependent viscosity: hc = h0 exp[c(1 - z/L0)], where h0 is the viscosity at the bottom of the crust, c is a constant; c > 0 for DDV model and c = 0 for uniform viscosity (UNV) model, z is the depth, and L0 is a reference length-scale. The visco-elastic mantle has a spatially uniform viscosity hm. The inflation and/or deflation of sill-like magma chamber is implemented by using the split node method developed by Melosh and Raefsky [1981, Bull. Seism. Soc. Am., 71, 1391-1400]. UNV model with c = 0 employed in this study shows that the inflation-induced surface uplift would abate with time by visco-elastic relaxation. The post-inflation subsidence would erase the uplift in ~ 50 - 100 times Maxwell relaxation time of the crust

  11. 频域眼前段光学相干断层扫描对周边虹膜切除术前后前房角的研究%Evaluation of the anterior chamber angle before and after iridectomy by spectral domain-anterior segment optical coherence tomography

    Institute of Scientific and Technical Information of China (English)

    袁永刚; 梁纳; 马胜生; 郑东健

    2014-01-01

    目的 应用频域眼前段光学相干断层扫描(OCT)分析周边虹膜切除术前后前房角的变化.方法 原发性前房角关闭者32例(40只眼)行周边虹膜切除术,术前、术后2d、2个月使用频域眼前段OCT进行前房角测量,比较500 μm/750 μm前房角角度(ACA500/ACA750)和500 μm/750μm前房角开放距离(AOD500/AOD750)等指标.结果 各指标在术前、术后差异有统计学意义,术后2d、2个月相应指标差异无统计学意义.结论 原发性前房角关闭行周边虹膜切除术后前房角增宽,可缓解瞳孔阻滞,预防前房角进一步关闭,频域眼前段OCT可进行术前术后的非接触检查,实现前房的生物统计学测量.%Objective To evaluate the change of the anterior chamber angle before and after iridectomy by spectral domain-anterior segment optical coherence tomography(SD-AS OCT).Methods The clinical trial was carried out in 40 eyes of 32 cases with primary angle closure(PAC).500μm/750μm anterior chamber angle (ACA500/ACA750) and 500μm/750μm angle opening distance (AOD500/AOD750) were imaged with SD-AS OCT before and after iridectomy.Results There were statistical significant differences between preoperation and post-operation in ACAS00/ACA750 and AODS00/AOD750.No significant differences of above indexes were found between 2 days and 2 months after surgery.Conclusion The anterior chamber angle becomes wider in PAC patient after iridectomy.This improvement can relieve pupil block and prevent further chamber angle closure.SD-AS OCT can be used to carry out a noncontact biometrical measurement of anterior chamber before and after surgery.

  12. 超声生物显微镜观察弹性开放襻前房型人工晶状体对眼前段结构的影响%The influence of flexible open-loop anterior chamber intraocular lens on the structure of ocular anterior segment

    Institute of Scientific and Technical Information of China (English)

    陈伟蓉; 刘奕志; 陈秀琦; 程冰; 刘玉华

    2001-01-01

    Objective To evaluate the therapeutic effects and safety offlexible open-loop anterior chamber intraocular lens (FOAC-IOL). Methods By ultrasound biomicroscopy, the positions of the haptics of FOAC-IOL in 20 patients (20 eyes) and the relationships of the haptics with iris and anterior chamber angle structures were observed postoperatively to evaluate the impact of these lenses on the structures of ocular anterior segment. Follow-up duration was from 6 to 20 months. Results Among 40 IOL′s haptics, twenty-six haptics were fixed at the recess of the chamber angle ;and other fourteen haptics penetrated the iris and invaded into the ciliary stroma, which caused recurrent uveitis. There was 1 eye with eccentric lens. There were 8 eyes with anterior synechiae of iris, which were related to the haptics of intraocular lens. Conclusions Ultrasound biomicroscopy works well in dynamic observation of the influence of intraocular lens on ocular anterior segment. The haptics of flexible open-loop anterior chamber intraocular lens should be modified.%目的 评价弹性开放襻一体型前房型人工晶状体(anterchamberintraocularlens,AC-IOL)植入术的疗效及其安全性。方法 应用超声生物显微镜观察20例(20只眼)弹性开放襻一体型AC-IOL植入术后患者IOL襻的位置,以及其与虹膜及房角结构的关系,从而评价IOL对眼前段结构的影响。随访时间6~20个月。结果 40个IOL襻中,26个襻固定于房角隐窝;14个襻(8只眼)穿过虹膜侵入至睫状体实质内,并伴有反复发作的葡萄膜炎。术后8只眼虹膜前粘连与IOL襻有关。结论超声生物显微镜检查是动态了解IOL对眼前段结构影响的有效方法。AC-IOL襻的设计有待进一步改进。

  13. A case involving an Ahmed™ glaucoma valve transferred from the vitreous into the anterior chamber of the eye with a silicone oil tamponade for the treatment of neovascular glaucoma

    Directory of Open Access Journals (Sweden)

    Miki M

    2013-02-01

    Full Text Available Michiko Miki, Mari Ueki, Tetsuya Sugiyama, Shota Kojima, Tsunehiko IkedaDepartment of Ophthalmology, Osaka Medical College, Takatsuki, JapanPurpose: To report the short-term efficacy and safety of the transfer of an Ahmed™ glaucoma valve (AGV™ tube from the vitreous into the anterior chamber, in a patient with neovascular glaucoma who had undergone pars plana AGV™ implantation and ultimately needed a silicone oil tamponade.Case: A 41-year-old male with proliferative diabetic retinopathy in both eyes was referred to us for treatment in December 2009. Although the patient previously underwent several surgeries, he ultimately lost vision in his right eye. His left eye suffered from neovascular glaucoma after undergoing a pars plana vitrectomy for tractional retinal detachment. After several vitreous and glaucoma surgeries, the patient underwent implantation of a pars plana AGV™. Postoperatively, although his intraocular pressure was stabilized at approximately 10 mmHg, he had repeated vitreous hemorrhage and hyphema without improvement. He ultimately underwent PPV with a silicone oil tamponade and at the same time, the AGV™ tube was pulled out from the vitreous and inserted into the anterior chamber in order to avoid complications caused by the silicone oil.Results: At 19 months postoperative, the patient’s intraocular pressure had stabilized at 10 mmHg with no recurrence of vitreous hemorrhage and hyphema. Eventually, he lost vision in his left eye because of cerebral hemorrhage.Conclusion: The findings show that insertion of a pars plana AGV™ tube into the anterior chamber in a patient undergoing a silicone oil tamponade is both effective and safe in the short-term.Keyword: tube implantation, glaucoma surgery, tube transfer, pars plana, proliferative diabetic retinopathy, intraocular pressure

  14. 全景超声生物显微镜对人眼睫状沟距离及前房直径的测量%Correlation between anterior chamber angle diameter and ciliary sulcus distance measured by Suowei panoramic 50-MHz digital ultrasound blomicroscopy

    Institute of Scientific and Technical Information of China (English)

    李德姣; 王宁利; 牟大鹏

    2011-01-01

    ciliary sulcus distance in different AC depth population and offer a clinical guide.Methods The anterior chamber angle diameter and ciliary sulcus distance were measured in 30 right eyes with shallow anterior chamber caused by suspect glaucoma and 30 right eyes with deep anterior chamber dut to the high myopia with Suowei panoramic 50-MHz digital ultrasound biomicroscopy.Three horizontal B-scans with the focal plane approximately at a depth corresponding to the iris plane were acquired for each eye.The differences of the anterior chamber angle diameter and ciliary sulcus distance were calculated and compared between the two groups.The correlation of the anterior chamber angle diameter and ciliary sulcus distance were evaluated in respective group.Results In shallow AC group,the mean angle diameter was(11.49+0.75)mm,the mean ciliary sulcus distance was (10.97±0.86)mm with the mean standard deviation of the difference of(-5.14± 0.55)mm,showing a statistically significant difference(t =-5.092,P =0.000).In shallow AC group,linear regression analysis showed a statistically significant correlation between ciliary sulcus distance and angle diameter(R2=0.593,P=0.000)and the Pearson's correlation coefficient was 0.767.In deep AC group,the angle diameter was(12.69±0.67)mm;while ciliary sulcus distance was(12.31 ± 0.61)mm with the mean slandard deviation(-0.38 ± 0.17)mm,which was statistically significantly different(t=-5.531,P=0.000).The ciliary sulcus distance was found to be linear correlation with the angle diameter(R2 =0.699,P=0.000)and Pearson' s correlation coefficient of 0.836.Conclusions Panoramic ultrasound biomicroscopy is an useful tool to the measurement of ciliary sulcus distance.This study exhibited that the ciliary sulcus distance is significant associated with the anterior chamber angle diameter,which may offer a guide for phakic intraocular lens implantation.

  15. CATARACT SURGERY AND INTRAOCULAR LENS POWER CALCULATION IN A PATIENT WITH ANTERIOR MEGALOPHTHALMOS WITH NORMAL SIZED CRYSTALLINE LENS; CASE REPORT

    Directory of Open Access Journals (Sweden)

    Glišić Selimir

    2015-12-01

    Full Text Available Cataract surgery and intraocular lens power calculation is challenging in patients with anterior megalophthalmos and cataract, with postoperative refractive surprise frequently reported. Deep anterior chamber in these patients substantially influence effective lens position. To minimize possibility of refractive surprise, we used Haigis formula that takes into account anterior chamber depth in the lens power calculation for our patient. Cataract was managed by phakoemulsification with standard intraocular lens implanted in the capsular bag. Postoperatively, satisfying refractive result was achieved and refractive surprise was avoided.

  16. 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.

  17. Evaluation of Anterior Segment's Structures in Tilted Disc Syndrome

    Science.gov (United States)

    Ozsoy, Ercan; Demirel, Ersin Ersan; Cumurcu, Tongabay

    2016-01-01

    Purpose. To evaluate anterior segment's structures by Pentacam in patients with tilted disc syndrome (TDS). Methods. Group 1 included forty-six eyes of forty-six patients who have the TDS. Group 2 including forty-six eyes of forty-six cases was the control group which was equal to the study group in age, gender, and refraction. A complete ophthalmic examination was performed in both groups. All cases were evaluated by Pentacam. The axial length (AL) of eyes was measured by ultrasound. Quantitative data obtained from these measurements were compared between two groups. Results. There was no statistically significant difference for age, gender, axial length, and spherical equivalent measurements between two groups (p = 0.625, p = 0.830, p = 0.234, and p = 0.850). There was a statistically significant difference for central corneal thickness (CCT), corneal volume (CV), anterior chamber angle (ACA), and pupil size measurements between two groups (p = 0.001, p = 0.0001, p = 0.003, and p = 0.001). Also, there was no statistically significant difference for anterior chamber depth (ACD), anterior chamber volume (ACV), and lens thickness (LT) measurements between two groups (p = 0.130, p = 0.910, and p = 0.057). Conclusion. We determined that CCT was thinner, CV was less, and ACA was narrower in patients with TDS. There are some changes in the anterior segment of the eyes with tilted disc. PMID:27648303

  18. 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

  19. Evaluation of Changes in Anterior Segment Configuration by Ultrasound Biomicroscopy after Phacoemulsification and Foldable Intraocular Lens Implantation

    Directory of Open Access Journals (Sweden)

    ilhami Salcan

    2011-08-01

    Full Text Available Purpose: To quantify the configuration changes in anterior segment structures after cataract extraction using ultrasound biomicroscopy (UBM. Material and Method: 33 eyes of 33 patients (21 male, 12 female; mean age: 69.0±8.3 years with senile or presenile cataracts undergoing cataract surgery were prospectively studied. UBM was performed for each patient before and 1 month after surgery. At each UBM examination, axial images of the anterior chamber and radial sections of the angle in four quadrants were obtained. The measurements were performed by using the calipers included in the equipment software and UBM Pro2000® software. Results: After cataract surgery, we determined statistically significant increases in anterior chamber depth and angle parameters (p=0.001. We found that the postoperative increases in anterior chamber depth, angle recess area, angle opening distance 250 and angle opening distance 500 were 1.3, 1.4, 1.7 and 1.5 times, respectively, when compared with the preoperative levels. Decreases in acceleration and increases in y-intercept were determined in 4 quadrants postoperatively by of linear regression analysis of anterior chamber angle and these were also statistically significant (p=0.001. Discussion: UBM gives both qualitative and quantitative valuable information about anterior segment structures. We think that UBM may be a useful tool for evaluation of patients with cataract and occludable and/or narrow angles undergoing cataract surgery for therapeutic purpose. (Turk J Ophthalmol 2011; 41: 200-6

  20. Technical Note : A direct ray-tracing method to compute integral depth dose in pencil beam proton radiography with a multilayer ionization chamber

    NARCIS (Netherlands)

    Farace, Paolo; Righetto, Roberto; Deffet, Sylvain; Meijers, Arturs; Vander Stappen, Francois

    2016-01-01

    Purpose: To introduce a fast ray-tracing algorithm in pencil proton radiography (PR) with a multilayer ionization chamber (MLIC) for in vivo range error mapping. Methods: Pencil beam PR was obtained by delivering spots uniformly positioned in a square (45x45 mm(2) field-of-view) of 9x9 spots capable

  1. Effects of age on ocular anterior segment dimensions measured by optical coherence tomography

    Institute of Scientific and Technical Information of China (English)

    QIN Bing; ZHOU Xing-tao; HUANG David; CHU Ren-yuan

    2011-01-01

    Background Older subjects tend to have smaller ocular anterior segment. The present study aimed to measure anterior segment dimensions with optical coherence tomography (OCT) and quantitatively assess the effect of age and other factors.Results Sixty-six eyes of 33 normal subjects (aged 22-65 years, 19 Asians, 14 Caucasians) were enrolled. For every 1 year of age, corneal diameter was 0.033 mm narrower (P <0.01), anterior chamber width was 0.031 mm narrower (P <0.01), corneal vault was 0.016 mm lower (P<0.01), and anterior chamber depth was 0.025 mm lower (P<0.01). Asian eyes had smaller corneal diameter (P=0.035) and anterior chamber width (P=0.015) compared with those of Caucasian eyes. Body height showed positive correlation with corneal diameter (0.039 mm per centimeter of height, P <0.01) and corneal vault (0.024 mm per centimetre of height, P <0.01). Gender did not have an independent effect on anterior segment dimensions.Conclusions Anterior segment dimensions were smaller in older subjects. Age-related changes may affect the tolerability of long-term implants such as phakic intraocular lens.

  2. Refraction and eye anterior segment parameters in schizophrenic patients

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    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.

  3. Coloboma típico associado à síndrome de clivagem de câmara anterior e microcórnea: descrição de um caso Typical coloboma associated with anterior chamber cleavage syndrome, and microcornea: description of one case

    Directory of Open Access Journals (Sweden)

    Ana Regina Cruz Vlainich

    2004-02-01

    Full Text Available Os autores descrevem associação rara bilateral de coloboma da íris, coróide, retina e cabeça do nervo óptico, microcórnea e deficiência de clivagem de câmara anterior. Fazem também uma abordagem quanto à embriologia e à dificuldade de identificar se a causa da queda contínua e insidiosa da visão é devida ao próprio coloboma ou a outra doença associada, como o glaucoma. Os exames subsidiários disponíveis como campo visual, fundoscopia e tonometria, são de pouca confiabilidade devido ao nistagmo e à baixa acuidade visual.The authors describe a rare association of bilateral typical coloboma, microcornea and anterior chamber cleavage deficience. They also discuss the embriology and the difficulties to identify if the continuous and insidious vision impairment is due to coloboma or to other associated disease, like glaucoma. Supplementary tests, such as visual field, ophthalmoscopy, and tonometry are not reliable because of the presence of nistagmus and low visual acuity.

  4. Cervicoplastia anterior Anterior cervicoplasty

    Directory of Open Access Journals (Sweden)

    Lucas Gomes Patrocínio

    2004-10-01

    Full Text Available Muitos pacientes buscam correção estética da frouxidão da pele do pescoço, depósito de gordura na região submentoneana ou bandas de platisma. Em grande parte dos casos a ação medial, via cervicoplastia anterior é necessária. OBJETIVO: Demonstrar a casuística e avaliar os resultados e complicações com a técnica de cervicoplastia anterior no Serviço de Otorrinolaringologia da Universidade Federal de Uberlândia. FORMA DE ESTUDO: Relato de série. PACIENTES E MÉTODOS: Quarenta e dois pacientes, entre 39 e 65 anos de idade, sendo 40 (95,2% do sexo feminino e 2 (4,8% do masculino, foram submetidos a cervicoplastia anterior. Retrospectivamente foram avaliados resultados e complicações. RESULTADOS: Destes, 34 apresentaram resultados satisfatórios, 4 apresentaram déficit estético notado somente pelo cirurgião, 3 apresentaram déficit estético notado somente pelo paciente e 1 apresentou déficit estético necessitando cirurgia revisional. Ao estudo fotográfico, todos os pacientes apresentaram melhora do perfil cervical, redução das bandas de platisma e da frouxidão da pele, estabilização da musculatura cervical e acentuação do ângulo cervicomental, em graus variados. Houve complicação em 2 casos (discreto serohematoma e cicatriz um pouco alargada. CONCLUSÃO: A cervicoplastia, associada ou não à tração lateral pela ritidoplastia, é uma técnica que produz resultados satisfatórios na grande maioria dos casos.Many patients look for aesthetic correction of the laxity of neck skin, submandibular fat deposit or platisma bands. In a large part of the cases, medial action, through anterior cervicoplasty is necessary. AIM: To demonstrate the casuistic and to evaluate the results and complications with anterior cervicoplasty technique in the Otorhinolaryngology Service of the Federal University of Uberlândia. STUDY DESIGN: Serie report. PATIENTS AND METHODS: Forty-two patients, between 39 and 65 years of age, being 40 (95

  5. 利用CBCT分析上颌前牙区微种植体支抗植入的安全范围%Quantitative study of maxillary anterior bone depth for micro-implant anchorage placement using cone beam CT

    Institute of Scientific and Technical Information of China (English)

    夏文倩; 顾永佳; 高美琴

    2013-01-01

    Objective:To investigate the bone depth of maxillary anterior interdental area for orthodontic micro-implant an-chorage. Methods:Maxillary anterior alveolar bone of 30 adults was scanned and reconstructed by cone beam CT , the mesio-distal interdental distance and labial-palatal bone depth were measured at 4,6,8,10 and 12 mm from the alveolar crest be-tween upper anterior dental roots. Results: The mesio-distal distance between central incisors was the widest in all measure-ment levels, while the labial cortical bone thickness was the thinnest. At the 8 mm-level,the shortest mesio-distal distance was between the roots of central and lateral incisors. At or above the 8 mm-level , the labial-palatal bone depth was the thinnest between central incisors, but the thickest between central and lateral incisors. It was seen in only 6 cases that the root length exceeded 12 mm. Conclusion:This study provides suitable bone thickness and bone depth for micro-screws place-ment of maxillary anterior region.%目的:利用锥形束CT(cone beam computed tomography,CBCT)对上颌前牙区各根间的近远中及唇腭侧骨质厚度进行测量分析,为确定正畸治疗植入微种植支抗的安全范围提供参考。方法:对30例成人患者上颌前牙区行CBCT扫描及三维重建,测量距上颌牙槽嵴顶4、6、8、10、12 mm水平上颌中切牙、侧切牙、尖牙根间区近远中向、唇腭向的距离。结果:上中切牙牙根间至牙槽嵴顶4、6、8、10 mm近远中间距均最宽,在距牙槽嵴顶8 mm 水平,中切牙与侧切牙牙根间近远中向距离最窄;中切牙牙根间骨厚度在唇腭向距牙槽嵴顶8 mm及以上水平最薄,中切牙与侧切牙牙根间骨厚度最厚。30例中有6例前牙区各牙根长度均>12 mm,其根间近远中向距离距牙槽嵴顶12 mm水平均较宽。结论:通过对扫描后颌骨影像的分析,明确了前牙区各牙根间骨量,为确定植入微种植支抗的安全范围提供参考。

  6. Scleral spur visibility of anterior chamber angle measured by Fourier optic coherence tomography%傅立叶光学相干断层扫描检测眼房角巩膜突可见性分析

    Institute of Scientific and Technical Information of China (English)

    张海涛; 徐英英; 王保君; 朱红军

    2011-01-01

    Objective To assess visibility of scleral spur in images of anterior chamber angle measured by the CAM model of Fourier optic coherence tomography (OCT). Methods Subjects aged 40 years or older were selected from outpatients in our opthalmologic clinic. All participants underwent standard ocular examinations, and anterior chamber angle was measured by CAM-L model of RTVue-OCT (Optovue Inc,USA) and gonioscopy. Visibility of scleral spur in OCT images and its related factor were analyzed. Results 98 subjects (98 eyes) aged (63.3±10.5)y included 62 females (63.3%) were selected in this study. There were 286 in 392 quadrants (73.0%) with visualized scleral spur, which had significant difference among local bulbar conjunctiva thickened or not (P<0.01). Logistic multiple regression showed that the visibility of scleral spur was not associated with gender, age, gonioscope grades (P>0.05), but significant associated with local bulbar conjunctiva thickened (OR=0.113, P<0.01) and quadrants (OR of superior/temporal=0.210, OR of inferior/temporal=0.340, P<0.01), of which there were different scleral spur visibility in superior and inferior quadrants compared with temporal(OR=0.210, 0.340, P<0.01). Angle status was still identified in 80.2% quadrants on condition that scleral spur was not visualized. Conclusions Fourier optic coherence tomography has good feasibility to detect anterior chamber angle as an alternative method, and may supply helpful information to estimate the pathogenesis of angle closure glaucoma.%目的 探讨傅立叶光学相干断层扫描仪CAM模块房角测量图像中巩膜突可见性及其影响因素.方法 连续选择本院眼科门诊40岁及以上患者,所有受试者均接受眼科常规项目检查,房角均分别接受Rtvue OCT(Optovue Inc,USA)CAM模块和房角镜检查.分析OCT图像中巩膜突的可见性及其影响因素.结果 受试者共98例(98眼),年龄(63.3±10.5)岁,其中女性62例(63.3%).在392

  7. 玻璃体切除术后无晶状体眼前房灌注下人工晶状体悬吊术%Intraocular lens ciliary sulcus suspension in aphakic vitrectomized eyes under anterior chamber perfusion

    Institute of Scientific and Technical Information of China (English)

    杨艳; 梁军; 张伟

    2015-01-01

    目的:观察25 G前房灌注下经3.0 mm切口二期睫状沟悬吊折叠型人工晶状体(IOL)治疗晶状体玻璃体切除术后无晶状体眼的临床效果。方法回顾性非对照病例分析。我院2012年1月至2013年12月因严重玻璃体视网膜病变曾行晶状体玻璃体切除术的无晶状体眼31例(31眼),术前裸眼视力为数指~0.12,最佳矫正视力0.15~0.8。玻璃体术后>6个月。二期于25 G前房灌注下经3 mm角膜缘切口植入IOL缝线固定于睫状沟。术后随访3~6个月,观察视力、眼压、角膜内皮细胞计数、IOL位置和并发症发生情况。统计学方法为配对t检验。结果术后3~6个月,裸眼视力为0.1~0.8,较术前提高(P0.01)。术后3个月角膜内皮细胞计数平均(1789±321)个/ mm2,与术前的(1837±289)个/mm2比较,差异无统计学意义(P>0.01)。29眼(93.55)IOL位置居中,另2眼(6.45%)中1眼轻度偏中心,1眼轻度倾斜。1眼术后轻度玻璃体积血。结论在微创25 G前房灌注下,经3.0 mm切口二期睫状沟悬吊折叠型IOL治疗晶玻切术后无晶状体眼,创伤小、眼压维持稳定。%Objective To evaluate the clinical efficacy of suture fixation to ciliary sulcus of a foldable intraocular lens ( IOL ) with the 25 G anterior chamber perfusion in eyes that had pars plana vitrectomy combined with lensectomy. Methods This is a retrospective non-comparative study. The medical data of 31 eyes of 31 patients who had vitrectomy combined with lensectomy surgery for severe vitreoretin opathy from Jan, 2012 to Dec, 2013 were reviewed. The underlying vitreoretinal diseases were complicated ocular trauma ( n = 16 ) , proliferative vitreoretinopathy ( n = 8 ) , proliferative diabetic retinopathy (n= 4), and lens dislocation in vitreous cavity (n=3). The uncorrected visual acuity (VA) of the 31 eyes was from LogMar 6. 64 to LogMar 3. 06 and the best corrected visual acuity ( BCVA) was from LogMar 2. 74 to LogMar 0. 097. In addition, the preoperative

  8. Analysis the Curative Effect of 20 Cases Neovascular Glaucoma With Anterior Chamber Angle Closure by Combined Surgey%20例闭角型期新生血管性青光眼联合手术疗效分析

    Institute of Scientific and Technical Information of China (English)

    庞彦利

    2016-01-01

    Objective To analyse the therapeutic effect of neovascular glaucoma (NVG) with anterior chamber angle closure.MethodsTotally 20 patients with NVG from April 2014 to August 2015 in our hospital, which the angle closure period, 5 patients with light perception ang 15 patients without light perception. According to the thickness of ball conjunctiva, they were divided to two groups (A,B). group A were with thin conjunctiva, underwent the cyclocryotherapy combined with peripheral retinal cryotherapy. 15 cases in group B underwent combined trabeculectomy with panretinal photocoagulation or peripheral retinal cryotherapy. according to their refractive status 0.25 mg/ml mitomycin C was applicatied for 3 to 5 minutes, and after operation 0.3 ml 5-FU was subconjunctived to reduce the scarring of the ifltering bleb. The patients were followed up for 3 months to observe the intraocular pressure, complications and the relief of pain in the eyes.Results In group A, preoperative intraocular pressure (IOP) was (50.12±6.20) mm Hg, and in group B it was (51.03±6.13) mm Hg, There was no signiifcant difference. On the 3rd postoperative day, IOP in group A was (28.63±5.74) mm Hg, in group B was (40±6.25) mm Hg, both were lowered signiifcantly. At 1 week after operations,the IOP were (21.63±5.86) mm Hg and (13±4.42) mm Hg, still lower than the preoperative. At one months after operations,the IOP were (25.31±4.72) mm Hg and (17±2.17) mm Hg, still lower than the preoperative. In group A ,the foreign body sensation, pain and anterior chamber exudation were significantly higher than that in B group, and in group B the incidence of anterior chamber hemorrhage was higher.Conclusion Correct choice of individuated surgical procedures in neovascular glaucoma can effectively lower the IOP, and relieve the pain of them.%目的:观察闭角期新生血管青光眼的治疗效果。方法回顾性分析2014年4月~2015年8月我院20例新生血管青光眼的临床资料,均为新生

  9. 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.

  10. 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.

  11. New Management of Malignant Glaucoma by Phacoemulsification with Posterior Chamber Foldable Intraocular Lens Implantation

    Institute of Scientific and Technical Information of China (English)

    GeJian; GuoY

    1999-01-01

    Objective:To investigate the feasibility of phacoemulsification with posterior chamber foldable intraocular lens implantation in the management of malignant glaucoma. Patients and Methods:Fourteen patients with malignant glaucoma diagnosed in the Department of Glaucoma were enrolled in the study.12 patients developed malignant glaucoma after filtration surgery.1 developed after peripheral iridectomy.1 patient developed malignant glaucoma without any clear cause.Cataract phacoemulsification was performed.Posterior chamber intraocular foldable lens was implanted in 10 cases of patients.Results:All 14 patients were cured wiht normal intraocular pressure,normal anterior chamber depth and increased visual acuity.Conclusion:Phacoemulsification with posterior chamber foldable intraocular lens implantation is a good alternative in treating malignant glaucoma.

  12. Quantitative observation on changes of anterior segment by ultrasound biomicroscopy after posterior chamber phakic intraocular lens implantation%UBM量化观察有晶状体眼后房型人工晶状体植入术前后眼前节形态的变化

    Institute of Scientific and Technical Information of China (English)

    王瑞娜; 郑广瑛; 王松田; 王洁; 赵建国; 郭红亮; 赵丽君

    2011-01-01

    ObjectiveThe objective is to study the safety and effectiveness of implantation of posterior chamber phakic intraocular contact lens (ICL) by observing the changes in anterior segment using ultrasound biomicroscopy (UBM). Methods It was a perspective study. The study sampled 30 high myopia patients (30 eyes) who were treated with posterior chamber phakic ICL implant. Central anterior chamber depth (ACD), trabecular-iris angle (TIA), angle opening distance (AOD500), trabecular-ciliary processes distance (TCPD) and iris-ciliary processes distance (ICPD) were measured using UBM preoperatively,3 months and 1 year postoperatively. The distance from ICL to the central surface of lens and peripheral lens and intra-ocular pressure were measured postoperatively and examined using slit-lamp biomicroscope. Oneway ANOVA was used to analyze the distance between peripheral surface of ICL and the lens. One-way repeated measures ANOVA and Bonferroni were conducted. Results Preoperatively, 3 months and 1 year postoperatively, ACD were(3. 16 ± 0. 08 ) mm, ( 2. 76 ± 0. 13 ) mm, (2. 74 ± 0. 14) mm; AOD500 were (0.45 + 0.04) mm, (0.41 ± 0.04) mm, (0.41 ±0.03) mm; TIA were (35.00 ±3. 24)°, (32.47 ±3.56) °, (32. 40 ± 3. 23 ) °, respectively. There were significant difference in TIA, ACD and AOD ( P <0. 05) between preoperative and postoperative data. There was no significant difference between the two postoperative periods tested. TCPD and ICPD showed no significant difference between various time points ( F =0. 49, F =0. 57 ; P > 0. 05 ). Conclusions The decrease in ACD depth and correction in TIA and AOD were the noticeable changes observed in morphological structure of the ocular anterior segment after the ICL treatment. The incidence of complication did not increase as the result of the minor changes in morph structure during the course of the study. However, the long-term effects would require further long-term observation.%目的 应用超声生物显微镜(UBM)对

  13. 有晶状体眼后房型人工晶状体植入术后前房角的变化及其相关因素%The change in anterior chamber angle and related factors in collamer lens implantation

    Institute of Scientific and Technical Information of China (English)

    朱浩斌; 贾琰; 周激波

    2014-01-01

    目的 研究高度近视眼植入有晶状体眼后房型人工晶状体(PPC-ICL)后前房角(ACA)的变化及其相关因素.方法 前瞻性研究.收集2013年3月至2014年4月在上海交通大学医学院附属第九人民医院行PPC-ICL植入手术的中高度近视患者26例(45眼).术后平均随访(4.3±3.2)个月.Pentacam测量术前及术后ACA、前房深度、角膜曲率、PPC-ICL拱高(vault).IOLMaster测量白到白距离和眼轴长度.同时记录术前及术后UCVA、等效球镜度及IOP.采用配对t检验、Wilcoxon符号秩和检验、Pearson相关、Spearman秩相关、多元回归分析进行数据分析.结果 3点方位术后ACA宽度为27.44°-±5.24°,与术前43.23°±5.72°比较,差异有统计学意义(Z=-5.841,P<0.01).3点方位ACA宽度的变化量与PPC-ICL拱高、同方位术前ACA宽度呈正相关(r=0.556、0.530,P<0.01),术后ACA宽度与拱高、术前ACA宽度回归方程为ACA术后=4.860-0.009 vault±0.621 ACA术前(F=20.032,P<0.01).9点方位ACA宽度术后为26.82°±4.73°,与术前42.40°±5.81°比较,差异有统计学意义(t=20.890,P<0.01);9点方位ACA宽度的变化量与PPC-ICL拱高、同方位术前ACA宽度呈正相关(r=0.581、0.626,P<0.01),术后ACA宽度和拱高、术前ACA宽度回归方程为ACA术后=5.767-0.008 vault±0.586 ACA术前(F=24.775,P<0.01).结论 PPC-ICL植入术后水平方向ACA宽度显著变小,变化量和术前ACA宽度、拱高均呈正相关.%Objective To investigate the change in the anterior chamber angle and to analyze its related factors of phakic posterior chamber implantable collamer lens (PPC-ICL) implantation.Methods Twenty-six moderate and high myopic patients (45 eyes) who received PPC-ICL implants from March 2013 to April 2014 were included in this prospective study.The mean follow-up time was 4.3±3.2 months.Anterior chamber angle (ACA),anterior chamber depth (ACD),corneal curvature,and vault were measured with a Pentacam preoperatively and

  14. spark chamber

    CERN Multimedia

    A few cosmic rays pass through your body every second of every day, no matter where you are. Look at the spark chamber to your right – every flash is the track made by a cosmic ray from outer space. The spark chamber is filled with a special gas mixture. Cosmic rays knock electrons out of the atoms in the gas. These electrons accelerate towards high voltage metal strips layered throughout the chamber, creating sparks like little bolts of lightning.

  15. spark chamber

    CERN Multimedia

    A few cosmic rays pass through your body every second of every day, no matter where you are. Look at the spark chamber to your right – every flash is the track made by a cosmic ray from outer space. The spark chamber is filled with a special gas mixture. Cosmic rays knock electrons out of the atoms in the gas. These electrons accelerate towards high voltage metal strips layered throughout the chamber, creating sparks like little bolts of lightning.

  16. 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.

  17. Control technology assessment of hazardous waste disposal operations in chemicals manufacturing: in-depth survey report of E. I. Du Pont de Nemours and Company, Chambers Works incinerator, Deepwater, New Jersey

    Energy Technology Data Exchange (ETDEWEB)

    Anastas, M.Y.

    1984-01-01

    An in depth survey was conducted to assess control technology of hazardous waste disposal operations at the Chamber Works incinerator, Du Pont de Nemours and Company (SIC-2800), Deepwater, New Jersey, in October 1982. Area and breathing zone samples were analyzed for toluene (108883), ortho-chloronitrobenzene (88733), and para-chloronitrobenzene (100005). All concentrations were well below the relevant standards. Control and safety instrumentation consisted of an electrically operated interlock system that sensed process disturbances and shut down the furnace. Wastes were burned directly from tank trailers. Trailer vents were connected to a spot scrubbing system. The hose connections included a recirculation line that prevented the plugging of process and trailer discharge lines with dirt particles. Waste pumps were provided with explosion proof motors and double mechanical seals. The company had programs for worker education and evaluation of on the job performance. Air monitoring of selected air contaminants was done routinely. Minimum protective equipment required for working in the incinerator area included rubber gloves, hard hat, and butyl rubber covers for shoes. The author concludes that a state of the art hazard control system is in place at the facility.

  18. The effect of postoperative central vault on the anterior chamber after implantation of implantable contact lens V4c%有晶体眼后房型人工晶体 V4c 植入术后拱高对前房结构的影响

    Institute of Scientific and Technical Information of China (English)

    叶进; 袁长明; 王霁雪; 谢汉平

    2015-01-01

    目的:观察有晶体眼后房型人工晶体 V4c 植入术后拱高对前房结构的影响。方法对重庆普瑞眼科医院2014年11月2日至2015年2月5日开展的56眼有晶体眼后房型人工晶体 V4c 植入术进行回顾性研究。术前用房角镜检查房角并记录前房角色素分级,用 Pentacam 测量平均前房角宽度(ACA )、前房容积(ACV )。术后第1、3、6个月复诊时测量中央拱高和平均ACA 以及 ACV ,并记录前房角色素分级。对患者手术后3次复查的拱高与 ACA 减小的量、ACV 减小的量进行相关性分析。结果术后1个月56眼的拱高为250~765μm ,ACA 减小的量为(13.67±1.67)°,ACV 减小量为(94.23±17.02)mm3。术后第3个月55眼的拱高为239~761μm ,ACA 减小的量为(13.70±1.68)°,ACV 减小量为(93.6±17.48)mm3。术后第6个月51眼拱高为246~761μm ,ACA 减小的量为(13.60±1.69)°,ACV 减小量为(94.29±17.80)mm3。未发现色素为Ⅱ级的病例。将3次复查的中央拱高与 ACA 和 ACV 减小量进行相关性分析,呈正相关(P<0.05)。中央拱高越大,则 ACA 和 ACV 改变量越大。结论有晶体眼后房型人工晶体 V4c 植入术后前房角变窄,前房容积下降。中央拱高与 ACA 和 ACV 改变量呈正相关,合适的拱高对保持房角开放有积极的临床意义。%Objective To observe the effect of postoperative central vault on the anterior chamber after implantation of im-plantable contact lens V4c .Methods To carry out a retrospective study of 56 eyes with implantable contact lens V4c implantation in Chongqing Bright Eye Hospital from November 2 ,2014 to February 5 ,2015 ,examined anterior chamber angle before surgery ,the anterior chamber angular width (ACA) and anterior chamber volume (ACV) were measured by pentacam .the postoperative central vault and ACA and ACV during the first and third and sixth months after surgery

  19. Depth dose distribution in the water for clinical applicators of {sup 90}Sr + {sup 90}Y, with a extrapolation mini chamber; Distribuicao de dose em profundidade na agua para aplicadores clinicos de {sup 90}Sr + {sup 90}Y, com uma mini-camara de extrapolacao

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, Patricia de Lara; Caldas, Linda V.E., E-mail: patrilan@ipen.b, E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Oliveira, Mercia L., E-mail: mercial@cnen.gov.b [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2009-07-01

    This work determines the depth dose in the water for clinical applicators of {sup 90}Sr + {sup 90}Y, using a extrapolation mini chamber developed at the IPEN, Sao Paulo, Brazil, and different thickness acrylic plates. The obtained results were compared with the international recommendations and were considered satisfactory

  20. 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.

  1. 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.

  2. Wire Chamber

    CERN Multimedia

    1986-01-01

    Two wire chambers made originally for the R807 Experiment at CERN's Intersecting Storage Rings. In 1986 they were used for the PS 201 experiment (Obelix Experiment) at LEAR, the Low Energy Antiproton Ring. The group of researchers from Turin, using the chambers at that time, changed the acquisition system using for the first time 8 bit (10 bit non linear) analog to digital conversion for incoming signals from the chambers. The acquisition system was controlled by 54 CPU and 80 digital signal processors. The power required for all the electronics was 40 kW. For the period, this system was one of the most powerful on-line apparatus in the world. The Obelix Experiment was closed in 1996. To find more about how a wire chamber works, see the description for object CERN-OBJ-DE-038.

  3. 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

  4. Analysis of low-energy and high-frequency femtosecond laser for the construction of deep anterior donor corneal lamellae

    Directory of Open Access Journals (Sweden)

    Gustavo Victor

    2014-04-01

    Full Text Available Purpose: To evaluate the efficacy and reliability of a low-energy femtosecond laser with a high repetition rate for construction of deep anterior donor corneal lamellae. Methods: This was a prospective laboratory investigation. Twenty-five human corneal buttons were femtosecond laser cut to create thick anterior lamellae (diameter, 10mm; thickness, 500µm. The laser cuts were made using an LDV® femtosecond laser in a Ziemer® anterior chamber. To obtain a better edge, the lamellae were trephined with an 8mm trephine (Katena®. The central corneal thickness and the anterior lamellae were measured using a Mitutoyo® thickness gauge with an accuracy of 0.001mm. Results: The central thickness of the 25 corneas ranged from 500 to 705µm (mean, 584 ± 51µm. The thickness of the anterior lamellae ranged from 420 to 480µm (mean, 455 ± 12.7µm. The anterior lamellae diameters were 7.90 ± 0.1mm, and all laser cuts were round. The lamellar interfaces appeared regular by surgical microscopy. There were no cases of inter-lamellar adhesion. Conclusion: The LDV® femtosecond laser appears to be a safe and reliable instrument for cutting deep anterior lamellae from donor corneoscleral buttons. Minimal variation in donor lamellar depth with the laser will be useful for creating donor corneal tissue for deeper anterior lamellar keratoplasty or endothelial keratoplasty surgery or both from a single donor cornea.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Assessment of Anterior Segment Measurements with Swept Source Optical Coherence Tomography before and after Ab Interno Trabeculotomy (Trabectome) Surgery

    Science.gov (United States)

    Huang, Ping

    2016-01-01

    Purpose. To compare the changes of anterior segment parameters, assessed by swept source anterior segment optical coherence tomography (AS-OCT) after combined Trabectome-cataract surgery and Trabectome-only surgery in open angle glaucoma patients. Methods. Thirty-eight eyes of 24 patients with open angle glaucoma were scanned with swept source AS-OCT before and 4 weeks after combined Trabectome-cataract or Trabectome-only surgery. Intraocular pressure, number of medications, and AS-OCT parameters, such as angle opening distance at 500 and 750 μm from the scleral spur (AOD500 and AOD750), trabecular-iris space area at 500 and 750 mm2 (TISA500, TISA750), angle recess area at 500 and 750 mm2 (ARA500, ARA750), trabecular iris angle (TIA), anterior chamber depth (ACD), anterior chamber width (ACW), and anterior chamber volume (ACV), were obtained before the surgery. These parameters were compared to evaluate whether the outcome of the surgery differed among the patients after the surgery. The width of the trabecular cleft was also measured for both groups. Results. The reduction of IOP and number of medications was found to be statistically significant in both groups (p ACV, and angle parameters such as AOD 500/750, TISA 500/750, ARA 500/750, and TIA500 showed significantly greater changes from the preoperative values to postoperative 1st month values in combined Trabectome-cataract surgery group (p 0.05). There was no statistically significant difference between two groups for the width of the trabecular cleft (p = 0.7). Conclusion. Anterior chamber angle parameters measured with swept source AS-OCT may be useful for evaluating glaucoma patients before and after Trabectome surgery with or without cataract surgery. PMID:27795855

  10. Prótese de íris, na aniridia traumática, como tentativa de controlar glaucoma refratário provocado pela presença de óleo de silicone na câmara anterior: relato de caso Iris prosthesis in traumatic aniridia as an attempt to control refractory glaucoma induced by silicone oil in the anterior chamber: case report

    Directory of Open Access Journals (Sweden)

    Rogil José de Almeida Torres

    2005-06-01

    Full Text Available O objetivo deste trabalho é demonstrar a eficácia da prótese iriana na resolução do glaucoma refratário, provocado pela presença de óleo de silicone na câmara anterior. Trata-se de paciente que sofreu trauma por estilhaços de projétil de arma de fogo. A cirurgia vítreo-retiniana visou a remoção dos corpos estranhos intra-oculares e posicionamento da retina, que se encontrava descolada. Devido à ausência parcial do tecido iriano e a afacia, o óleo de silicone introduzido na câmara vítrea, para manter a retina colada, migrou para a câmara anterior e provocou gradativa diminuição do número de células endoteliais e aumento da pressão intra-ocular incontrolável clinicamente. Optamos pela fixação transescleral da prótese de íris para corrigir tais complicações. Após 45 meses de evolução, a acuidade visual estabilizou-se em conta dedos a 1 metro e a pressão intra-ocular em 14 mmHg. Concluímos que a tríade composta pela ausência do diafragma iriano, afacia e impossibilidade da remoção do óleo de silicone, devido a inexorável recorrência de descolamento de retina, deve levar o cirurgião a ponderar sobre a fixação transescleral da prótese de íris. Esta conduta poderá controlar a pressão intra-ocular e/ou preservar a transparência corneana, impedindo o contato do óleo de silicone com a malha trabecular e com o endotélio corneano.The objective of this report is to demonstrate the effectiveness of an iris prosthesis to treat a refractory glaucoma induced by silicone oil in the anterior chamber. This case is about a patient who suffered a trauma caused by firearm shrapnel. A vitreous-retinal surgery was performed to remove intraocular foreign matter and to realign the retina that was detached. Due to the partial traumatic aniridia, silicone oil that was introduced in the vitreous chamber to keep the retina in place migrated to the anterior chamber, resulting in the decrease of endothelium cells and

  11. Diffuse anterior retinoblastoma: current concepts

    Directory of Open Access Journals (Sweden)

    Yang J

    2015-07-01

    Full Text Available Jing Yang,1–3 Yalong Dang,1–3 Yu Zhu,1 Chun Zhang2,3 1Department of Ophthalmology, The First Affiliated Hospital, Zhengzhou University, Zhengzhou City, Henan Province, 2Department of Ophthalmology, Peking University Third Hospital, 3Clinical Stem Cell Research Center, Peking University Third Hospital, Beijing, People’s Republic of China Abstract: Diffuse anterior retinoblastoma is a rare variant of retinoblastoma seeding in the area of the vitreous base and anterior chamber. Patients with diffuse anterior retinoblastoma are older than those with the classical types, with the mean age being 6.1 years. The original cells of diffuse anterior retinoblastoma are supposed to be cone precursor. Patients most commonly present with pseudouveitis, pseudohypopyon, and increased intraocular pressure. The retina under fundus examination is likely to be normal, and the clinical features mimic the inflammation progress, which can often lead to misdiagnosis. The published diffuse anterior retinoblastoma cases were diagnosed after fine-needle aspiration biopsy running the potential risk of inducing metastasis. The most common treatment for diffuse anterior retinoblastoma is enucleation followed by systematic chemotherapy according to the patient’s presentation and clinical course. This review summarizes the recent advances in etiology (including tumorigenesis and cell origin, pathology, diagnosis, differential diagnosis, and new treatment. The challenges of early diagnosis and prospects are also discussed. Keywords: pathology, microenvironment, treatment, diagnosis 

  12. New Management of Angle-closure Glaucoma by Phacoemulsification with Foldable Posterior Chamber Intraocular Lens Implantation

    Institute of Scientific and Technical Information of China (English)

    Jian Ge; Yan Guo; Yizhi Liu; Mingkai Lin; Yehong Zhuo; Bing Chen; Xiuqi Chen

    2000-01-01

    Objective: To investigate the management of angle-closure glaucoma by phacoemulsification with foldable posterior chamber intraocular lens (PC-IOL) implantation. Design: Retrospective, noncontrolled interventional case series.Participants: In 36 eyes with angle-closure glaucoma (ACG), there were 18 eyes with primary acute angle-closure glaucoma (PACG), 14 eyes with primary chronic angle-closure glaucoma (PCCG), 3 eyes with secondary acute angle-closure glaucoma (SACG) and 1 eye with secondary chronic angle-closure glaucoma (SCCG).Intervention: Phacoemulsification with posterior chamber intraocular lens implantation.Main Outcome Measures: Postoperative visual acuity, IOP, axial anterior chamber depth.Results: After a mean postoperative follow-up time of 8.81 ± 7.45 months, intraocular pressure was reduced from a preoperative mean of 23.81 ± 17.84 mmHg to a postoperative mean of 12.54 ± 4. 73 mmHg ( P = 0. 001 ). Mean anterior chamber depth was 1.75 ± 0.48 mm preoperatively and 2.29 ± 0.38 mm postoperatively ( P = 0. 000).Best spectacle-corrected visual acuity in 36 eyes ranged from 0. 01 to 0. 7 (20/200 to 20/30) postoperatively, which was better than preoperative VA ranging from hand movement to 0.4 (20/50) ( P= 0. 000).Conclusion: Phacoemulsification with posterior chamber foldable intraocular lens implantation can be a good alternative in treating angle-closure glaucoma. Eye Science 2000; 16:22 ~ 28.

  13. New Management of Angle-closure Glaucoma by Phacoemulsification with Folable Posterior Chamber Intraocular Lens Implantation

    Institute of Scientific and Technical Information of China (English)

    JianGE; YanGuo; 等

    2002-01-01

    Objective:To investigate the management of angle-closure glaucoma by phacoemulsification with foldable posterior chamber intraocular lens (PC-IOIL)implantation.Design:Retrospective,noncontrolled interventional case series.Participants:In 36 eyes with angle -closure glaucoma(ACG).there were 18eyes with primary acute angle-closure glaucoma(PACG),14 eyes with primary chonic angle -closure glaucoma(PCCG),3 eyes with secondary acute angle-closure glaucoma (SACG) and 1 eye with secondary chronic angle -closure glaucoma(SCCG).Intervention:Phacoemulsification with posterior chamber intraocular lens implantation.Main Outcome Measures:Postoperative visual acuity,IOP,axial anterior chamber depth.Results:After a mean postoperative follow -time of 8.81±7.45 months,intraocular pressure was reduced from a preoperative mean of 23.81±17.84 mmHg to a postoperative mean of 12.54±4.73mmHg(P=0.001).Mean anterior chamber depth was 1.75±0.48 mm preoiperatively and 2.29±0.38mm postoperatively(P-0.000).Best spectacle-corrected visual acuity in 36 eyes ranged from 0.01 to 0.7(20/200 to 20/30)postoperatively,which was better than preoperative VA ranging from hand movement to 0.4(20/50)(P=0.000).Conclusion:Phacoemulsification with posterior chamber foldable intraocular lens implantation can be a good alternative in treating angle-closure glaucoma.Eye Science2000;16:22-28.

  14. Single needle iridoplasty in close anterior chamber for extensive iridodialysis in serions ocular trauma%采用闭合式单针法修复21例大范围虹膜根部离断的疗效分析

    Institute of Scientific and Technical Information of China (English)

    李灿; 陈康; 王一; 陈少军

    2011-01-01

    目的 探讨严重钝性眼外伤行前后节联合手术时对大范围虹膜根部离断修复简便有效方法.方法 对≥90°虹膜根部离断严重钝性眼外伤21例21眼,在联合行玻璃体切割术前行闭合式单针虹膜根部离断修复术,先切除脱入前房内的玻璃体,用粘弹剂将卷曲虹膜回复至原位,将预先穿入10-0尼龙线1 ml注射器针头自角膜缘1 mm 切口进针,将离断虹膜缝合至相应部位板层巩膜瓣下.如伴有睫状体离断者同时缝合离断的睫状体(6例);再行晶体切除及玻璃体切除术.结果 21眼虹膜均复位,瞳孔呈圆形或近圆形.瞳孔直径4~8 mm.大部分患眼视力均不同程度提高,其中15眼最佳矫正视力≥0.1.眼压:7.0~28.0(14.0±8.7)mmHg.4眼继发性青光眼,药物控制.结论 对伴大范围虹膜根部离断严重眼外伤前后节联合手术中,应用闭合式虹膜根部离断修复术,损伤小,操作简便,效果良好.%Objective To explore a simple and effective iridoplasty approach for extensive iridodialysis in serious ocular trauma during combining anterior and posterior segment operation. Metlods Twenty-one patients (21 eyes) with ≥90° iridodialysis were enforced single needle repairment in close anterior chamber before vitrectomy. Firstly vitreous body in anterior chamber was removed, then iris was recovered to the original position by viscoelastic fluid, 1 ml needle within 0/10 nylon suture came into anterior chamber from 1 mm to limbus corneae and then out from opposite scleral flap corresponding to injured iris. In the condition of 6 patents with ciliary body detachment, their ciliary body were sutured in the same time, after it with lenseetomy and vitreetomy. Results All 21 iris were reposition, with the pupil in round or like-round shape and its diameter from 4 to 8 mm. After operation, vision acuity was improved to some degree. Fifteen cases han their best corrected visual acuity (BCVA) were better than 0. 1. Their

  15. Evaluation of anterior segment parameters using pentacam in silicone oil-injected patients after pars plana vitrectomy

    Directory of Open Access Journals (Sweden)

    Burcu Çalik

    2013-01-01

    Full Text Available Background: The aim of this study is to evaluate anterior segment changes with Pentacam Scheimpflug camera after pars plana vitrectomy (PPV and silicone oil injection. Materials and Methods: In all, 44 eyes of 44 patients who underwent PPV by one surgeon were evaluated with Pentacam preoperatively, first week, and first month after surgery. The patients were divided into two groups, eyes with silicone injection after PPV and eyes with PPV and no endotamponade. Main outcome measures were preoperative and postoperative anterior chamber volume (ACV, anterior chamber depth (ACD, anterior chamber angle (ACA, and central corneal thickness (CCT obtained with pentacam. Results: Each group consisted of 22 patients. In both groups no significant difference was detected among preop and postop changes in ACV and ACA values ( p > 0.05. The increase in ACD in silicone oil-injected group and the decrease in ACD in PPV group at postop 1 week were statistically significant ( p < 0.05. The increase in CCT in silicone oil-injected group at postop 1 week and then decrease in postop 1 month were also significant ( p < 0.05. Surgically induced astigmatism (SIA was 3.7 Dioptry (D in silicone oil-injected group and 2.4 D in PPV group at postop 1 week. SIA decreased to 1.7 D and 1.5 D, respectively, at postop 1 month. Changes in SIA were significant ( p < 0.05. Conclusion: PPV effects cornea and anterior segment. Changes in cornea and anterior segment after PPV seem to return to preoperative values among 1 month after surgery.

  16. Chamber transport

    Energy Technology Data Exchange (ETDEWEB)

    OLSON,CRAIG L.

    2000-05-17

    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.

  17. Toxic Anterior Segment Syndrome following Phacoemulsification Secondary to Overdose of Intracameral Gentamicin

    Directory of Open Access Journals (Sweden)

    Yaran Koban

    2014-01-01

    Full Text Available Objective. To report a case of toxic anterior segment syndrome (TASS that was caused by inadvertent anterior chamber and cornea stromal injection with high dose gentamicin following cataract surgery. Methods. Case report. Results. We report a 72-year-old female patient who developed TASS that was caused by high dose gentamicin (20 mg/0.5 mL, which was inadvertently used during the formation of the anterior chamber and hydration of the corneal incision. Unlike previous cases, hyphema and hemorrhagic fibrinous reaction were seen in the anterior chamber. Despite treatment, bullous keratopathy developed and penetrating keratoplasty was performed. The excised corneal button was sent for histopathological examination. Conclusions. Subconjunctival gentamicin is highly toxic to the corneal endothelium and anterior chamber structures. Including it on the surgical table carries a potentially serious risk for contamination of the anterior chamber.

  18. Toxic Anterior Segment Syndrome following Phacoemulsification Secondary to Overdose of Intracameral Gentamicin

    Science.gov (United States)

    Koban, Yaran; Genc, Selim; Cagatay, Halil Huseyin; Ekinci, Metin; Gecer, Melin; Yazar, Zeliha

    2014-01-01

    Objective. To report a case of toxic anterior segment syndrome (TASS) that was caused by inadvertent anterior chamber and cornea stromal injection with high dose gentamicin following cataract surgery. Methods. Case report. Results. We report a 72-year-old female patient who developed TASS that was caused by high dose gentamicin (20 mg/0.5 mL), which was inadvertently used during the formation of the anterior chamber and hydration of the corneal incision. Unlike previous cases, hyphema and hemorrhagic fibrinous reaction were seen in the anterior chamber. Despite treatment, bullous keratopathy developed and penetrating keratoplasty was performed. The excised corneal button was sent for histopathological examination. Conclusions. Subconjunctival gentamicin is highly toxic to the corneal endothelium and anterior chamber structures. Including it on the surgical table carries a potentially serious risk for contamination of the anterior chamber. PMID:25574173

  19. 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.

  20. 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...

  1. Treatment for sudden attack of secondary glaucoma due to intumescent cataract by anterior chamber penetration using acupuncture knife%前房穿刺术治疗白内障膨胀期继发青光眼的临床分析

    Institute of Scientific and Technical Information of China (English)

    荆毓陶

    2013-01-01

    目的:探讨前房穿刺放液处理膨胀期白内障继发急性闭角型青光眼的急性发作的疗效及时机。方法:对30例30眼老年性白内障膨胀期引起的继发性急性闭角型青光眼患者的急性期,(术前眼压均在50mmHg以上,1kpa=7.5mmHg)在联合应用常规降眼压药物治疗未能有效降低眼压后,急诊采用15°穿刺刀在8倍放大倍率的手术显微镜下进行前房穿刺,轻压切口后唇缓慢放出房水。结果:所有患者经前房穿刺放液后高眼压及眼痛迅速缓解,其中25例眼压降至正常,术后眼压平均16mmHg,仅5例眼压偏高,维持在35mmHg左右,但视力提高不显著,其中3眼穿刺后5-8小时眼压再次升高遂再次放液。结论:15°穿刺刀在手术显微镜下前房穿刺放液比传统的注射针头穿刺放液损伤小反应轻,是治疗膨胀期白内障继发急性闭角型青光眼的急性发作辅助措施,可以缩短降眼压的时间以减轻患者痛苦,减轻因高眼压造成的视功能损害,避免了长时间大量应用常规降眼压药物可能引起的副作用,为白内障的进一步治疗创造了条件。%Objective To evaluate the clinical effects and opportunity of anterioi chamber penetration using acupuncture knife on treating the sudden attack of secondary glaucoma due to intumescent cataract. Methods anterior chamber penetration using 15° acupuncture knife was performed on thirty patients with the sudden attack of secondary glaucoma due to intumescent cataract. after topical anaestetic. Results The mean intralocular pressure was over 50mmHg(1Kp=7.5mmHg) before the penetration and reduced to16mmHg as soon as the penetration was finished. In 5 of the 30 cases , the mean postoperative intraocular pressure was 35mmHg.In 3 of the 30 case s, the postoperative intraocular pressure rised and performed anterior chamber penetration again.None of the patients fel painful during the opration and no

  2. 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...

  3. Changes of anterior segment after early implantation of posterior chamber phakic intraocular lens for correction of high myopia%ICL植入术治疗高度近视术后早期眼前节形态的变化

    Institute of Scientific and Technical Information of China (English)

    黎冬平; 刘磊; 李新宇; 栗静; 王虎杰; 杨硕

    2014-01-01

    目的:我们应用眼前节全景分析仪( Pentacam)测量有晶状体眼后房型人工晶状体( ICL )植入术手术前后前节形态指标,评价有晶状体眼后房型人工晶状体植入术的安全性及稳定性。  方法:选取行有晶状体眼后房型人工晶状体植入术治疗的高度近视患者48例90眼,术后随访6mo。 Pentacam眼前节全景分析仪测量各时间点的中央前房深度( ACD)、3∶00位前房角( ICA)、角膜像差( CA)、角膜曲率( K)和角膜厚度(CCT)等指标。使用SPSS 19.0统计软件,描述术前术后各指标的分布特征,采用配对t检验对各指标进行手术前后的差异性比较。  结果:所有观察指标各时间点均呈正态分布。 ACD、3∶00位ICA较术前降低( P<0.05)。 CA中,总像差( CTA )及低阶像差( CLOA)较术前无统计差异( P>0.05),高阶像差(CHOA)则较术前有所增加(P<0.05);K略有减小(P<0.05)。 CCT较术前比较均无统计学差异( P>0.05)。对于术后有统计学意义变化的指标,均在术后1 mo时即达到稳定状态。  结论:应用眼前节全景分析仪( Pentacam )观察有晶状体眼后房型人工晶状体植入术眼前节形态的变化主要有ICA变窄, ACD变小, CHOA增加, K减小,尚在安全范围内,6 mo随访中各值均保持稳定,未出现并发症,但远期效果需进一步随访观察。%AIM:To evaluate safety and stability of ICL implantation treatment of high myopia through the observation of anterior segment parameters such as ACD and ICA over time pre-and post-operation changes by Pentacam. METHODS:According to the proposed inclusion criteria, 90 eyes (48 patients) with high myopia who accepted ICL implantation treatment were selected.The mean follow-ups are 6 months.Anterior segment parameters such as ACD, ICA ( 3'clock ) , corneal aberration ( CA ) , K-value and CCT were

  4. The application of binocular indirect ophthalmomicroscope combined with anterior chamber maintainer in vitrectomy for complicated vitreoretinopathy%非接触双目间接眼底显微镜联合前房灌注在复杂玻璃体视网膜病变术中的应用

    Institute of Scientific and Technical Information of China (English)

    王永梅; 王莹; 楚艳华; 韩泉洪

    2012-01-01

    目的 观察使用非接触双目间接眼底显微镜(BIOM)联合前房灌注系统(ACM)行玻璃体切割术处理复杂玻璃体视网膜病变的临床疗效.方法 6例(6只眼)复杂玻璃体视网膜病变行玻璃体切割术时,为了避免医源性的脉络膜视网膜损伤,采用前房灌注来维持眼压,晶状体摘除及前部玻璃体切割后,切换至BIOM行玻璃体视网膜手术.临床随访3~11月,评估手术疗效及并发症.结果 6例BIOM联合ACM的玻璃体切割术在操作中未见明显困难.术后5例视力提高,1例无变化.主要长期并发症为低眼压、前部PVR、视网膜前膜.4例行硅油取出术后,视网膜在位. 结论 采用BIOM联合ACM行玻璃体切割术治疗复杂玻璃体视网膜病变安全、有效,在实践中具有可行性.%Objective To evaluate the clinical results of vitrectomy by using binocular indirect ophthalmomicroscope (BIOM) combined with anterior chamber maintainer (ACM) for complicated vitreoretinopathy.Methods Six cases (6 eyes) of complicated vitreoretinopathy were undergone vitrectomy,during which ACM was used to maintain intraocular pressure and prevent from iatrogenic injury of choroid and retina.After lens and anterior vitreous removal,vitrectomy was completed through a BIOM observation system.The follow-up time ranged from 3 months to 11 months.The effects and complications were analyzed.Results No obvious drawback was noticed during the 6 cases vitrectomy by using BIOM and ACM combination.The visual acuities improved in 5 cases and remained stable in 1 case after operation.The major long-term complications were hypotony,epiretinal membrane,and anterior proliferative vitreoretinopathy.Retinal reattached in 4 cases after silicone oil removal.Conclusions The vitrectomy combined BIOM with ACM is effective and safe for complicated vitreoretinopathy,and clinical results ascertained the practical feasibility of it.

  5. Anterior segment biometry using ultrasound biomicroscopy and the Artemis-2 very high frequency ultrasound scanner

    Directory of Open Access Journals (Sweden)

    Al-Farhan HM

    2013-01-01

    Full Text Available Haya M Al-Farhan, Reem N AlMutairiKing Saud University, College of Applied Medical Sciences, Department of Optometry and Vision Sciences, Riyadh, Kingdom of Saudi ArabiaPurpose: To compare the precision of anterior chamber angle (ACA and anterior chamber depth (ACD measurements taken with ultrasound biomicroscopy (UBM and the Artemis-2 Very High Frequency Ultrasound Scanner (VHFUS in normal subjects.Design: Prospective study.Methods: We randomly selected one eye from each of 59 normal subjects in this study. Two subjects dropped out of the study; the associated data were excluded from analysis. ACA and ACD measurements were obtained using the VHFUS and the UBM. The results were compared statistically using repeated-measures analysis of variance for the intraobserver repeatability, unpaired t-test, and limits of agreement.Results: The average ACA values for the UBM and the VHFUS (±standard deviation were 41.83° ± 5.03° and 33.36° ± 6.03°, respectively. The average ACD values were 2.96 ± 0.34 mm and 2.87 ± 0.31 mm. The intraobserver repeatability analysis of variance P-values for ACA and ACD measurements using UBM were 0.10 and 0.68, respectively; for the Artemis-2 VHFUS, the respective values were 0.68 and 0.09. The difference in ACA measurements was statistically significant (t = 8.41; P < 0.0001, while the difference in ACD values was not (t = 1.51; P < 0.13. The mean ACA difference was 8.50° ± 2.50°, and the limits of agreement were +13.30° to −3.60°. The mean ACD difference was 0.09 ± 0.27 mm, and the limits of agreement ranged from 0.61 mm to −0.43 mm. The mean difference percentage of ACD was 3.1% for both instruments.Conclusion: In case of the ACD, both instruments can be used interchangeably; however, with the ACA instruments, they cannot be used interchangeably.Keywords: anterior chamber angle, anterior chamber depth, Artemis-2 VHF scanner, ultrasound biomicroscope, normal eyes

  6. Anterior dislocation of an empty capsular bag in a pseudophakic eye: A rare case report

    Directory of Open Access Journals (Sweden)

    Hyung Bin Hwang

    2015-01-01

    Full Text Available Spontaneous intraocular lens (IOL dislocation is uncommon in the absence of any ocular areas with zonular weakness or trauma. There have been no reports of spontaneous capsular bag dislocation into the anterior chamber without an IOL. We report a rare, interesting case of spontaneous capsular bag anterior dislocation, without an IOL, into the anterior chamber with no history of genetic disease, ocular trauma, or pseudoexfoliation that might predispose to a zonular abnormality.

  7. Depth statistics

    OpenAIRE

    2012-01-01

    In 1975 John Tukey proposed a multivariate median which is the 'deepest' point in a given data cloud in R^d. Later, in measuring the depth of an arbitrary point z with respect to the data, David Donoho and Miriam Gasko considered hyperplanes through z and determined its 'depth' by the smallest portion of data that are separated by such a hyperplane. Since then, these ideas has proved extremely fruitful. A rich statistical methodology has developed that is based on data depth and, more general...

  8. Anterior iris-claw lens implantation with single paracentesis

    Directory of Open Access Journals (Sweden)

    Ahmet Özer

    2011-11-01

    Full Text Available In this study, the technique and results of iris-claw intraocular lens (IOL implantation with corneal incision and single paracentesis were presented. Eighteen eyes of 18 patients who underwent iris-claw implantation surgery with a single paracentesis were included in this prospective study. Iris-claw lens was grasped by its forceps and placed into the anterior chamber through superior corneal opening. While IOL was held by forceps, a blunt enclavation spatula was introduced through inferior paracentesis. Then the spatula was directed toward underneath of iris through pupil and toward sides where iris was entrapped into the claw by gentle push of iris through the slotted center of the lens haptics. Mean age of patients was 54.28±25.21 years (7-76 years. Mean anterior chamber depth was 4.07±0.32 mm and mean keratometric power was 43.01±2.73 D. Preoperative BCVA was 20/63 or better in 8 (44.4% patients. At the first postoperative month BCVA was 20/63 or better in 14 (77.8% patients. Preoperative mean spherical refraction was +11.05±2.62 D, preoperative astigmatism was 2.15±0.85. Postoperative mean spherical refraction was - 0.58±0.25 D and mean astigmatism was - 1.92±0.67 D. The most frequent postoperative complication was mild corneal edema seen in three patients that resolved completely during the first week with medical treatment. Irisclaw IOL implantation can be performed easily with corneal incision and single paracentesis. Single paracentesis does not increase surgical time or cause inconvenience during the procedure.

  9. Anterior ciliary sclerotomy: effect on corneal topography, globe integrity, and the role of a novel antifibrotic gel

    Science.gov (United States)

    Lamar, Peggy; Fernandez, Viviana; Manns, Fabrice; Dubovy, Sander; Zipper, Stanley; Sandadi, Samith; Nakagawa, Natsushi; Weiser, Marc; Malecaze, Francois; Parel, Jean-Marie A.

    2002-06-01

    To (1) quantify changes in corneal topography induced by radial anterior sclerostomy for restoring accommodation and, (2) assess safety and ant fibrosis activity of cross-linked sodium hyaluronic acid (cSHA) based gels in ACS procedures. Methods (ex-vivo study): 6 fresh human Eye-Bank eyes were used. A 15% Dextran solution was injected in the anterior chamber and the vitreous cavity, the corneal epithelium was removed by scraping, and the whole eye was immersed in 15% Dextran solution until corneal thickness reached a physiological value. The conjunctiva and tenon capsule were removed and the eye was mounted on a custom-made holder. Preoperative corneal topography was measured with a PAR corneal topography system. Five to eight 3mm-long linear equidistant anterior radial incisions starting from the limbus were performed in the sclera at 90% depth with a diamond blade. Postoperative corneal topography was measured. The files providing the pre and postoperative tangential curvature along meridians separated by 5 degrees were exported. The axial curvature along the 0 and 90-degree meridians before and after surgery were compared. Methods (in-vivo study): Of 24 rabbits, 4 were operated following Thornton's (90% depth incision) and 20 following Fukasaku's (100% depth) techniques (total peritomy, four 4mm long radial scleral incisions starting 0.5 mm from the limbus).

  10. Depth of origin of magma in eruptions.

    Science.gov (United States)

    Becerril, Laura; Galindo, Ines; Gudmundsson, Agust; Morales, Jose Maria

    2013-09-26

    Many volcanic hazard factors--such as the likelihood and duration of an eruption, the eruption style, and the probability of its triggering large landslides or caldera collapses--relate to the depth of the magma source. Yet, the magma source depths are commonly poorly known, even in frequently erupting volcanoes such as Hekla in Iceland and Etna in Italy. Here we show how the length-thickness ratios of feeder dykes can be used to estimate the depth to the source magma chamber. Using this method, accurately measured volcanic fissures/feeder-dykes in El Hierro (Canary Islands) indicate a source depth of 11-15 km, which coincides with the main cloud of earthquake foci surrounding the magma chamber associated with the 2011-2012 eruption of El Hierro. The method can be used on widely available GPS and InSAR data to calculate the depths to the source magma chambers of active volcanoes worldwide.

  11. ISR Intersection Vacuum Chamber

    CERN Multimedia

    1975-01-01

    This special vacuum chamber presenting a lateral opening at the beam crossing point is one of the many chambers specifically designed for a particular experiment. Here it is shown during assembly at the ISR mechanical worshop.

  12. 贝伐单抗兔眼前房注射后在眼组织的分布及其不良反应的研究%Distribution of bevacizumab in ocular tissue and its toxic effect after injection of anterior chamber

    Institute of Scientific and Technical Information of China (English)

    刘琳; 马翔; 季艳丽; 冶卓

    2011-01-01

    消失.结论 前房注射贝伐单抗1.25 mg对正常兔眼组织无明显的毒性作用和不良反应,注射后药物能快速分布于注射眼的前房角、虹膜、睫状体、脉络膜和视网膜,主要堆积在血管样组织中.%Background Bevacizumab has been widely used in the treatment of new blood vessel disease in ophthalmology.The investigation of the pharmacokinetics and safety after intracameral injection of bevacizumab can offer the basis for the management of iris neovascularization and neovascular glaucoma.Objective The present study was to observe the distribution of bevacizumab(avastin)in eye tissue and toxic effects following the injection of anterior chamber.Methods Twenty-four New Zealand albino rabbits were divided into two groups randomly.0.05 ml (1.25mg)of Bevacizumab was intracamerally injected into the left eyes in the experimental group,and a balanced salt solution of 0.05 ml was injected in the same way into the left eyes of the control group.The anterior segment of eyes and ocular fundus were examined by slit-lamp microscope and direct ophthalmoscope after injection.Intraocular pressure was measured and corneal endothelial microscopy was performed before and after the injections.Five rabbits of the two groups were sacrificed on the first day,the fourth day,the seventh day,the fourteenth day,and the thirtieth day after injection,and the eyeballs were enucleated for histopathological examination.The ultrastructure of eye tissue was observed under the transmission electron microscope on the fourth day and the thirtieth day,and then immunofluorescence staining were performed to assess the distribution of bevacizumab in the eye tissues.This experiment complied with the Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission(Version 1988).Results No abnormality in the cornea,lens,vitreous and retina was observed after the injection of bevacizumab under the slit lamp microscope and direct

  13. 眼外导光照明视网膜光凝联合前房注气在白内障玻璃体视网膜术中应用%Microscopically eye light illumination, retinal laser photocoagulation combined with gas anterior chamber tamponade in cataract joint vitreoretinal surgery

    Institute of Scientific and Technical Information of China (English)

    刘鹏飞

    2016-01-01

    目的 探讨显微镜下眼外导光照明、视网膜激光光凝联合前房注气在白内障联合玻璃体视网膜手术中的疗效及可行性.方法 回顾性分析2010年1月至2014年7月在唐山市眼科医院就治的47例(47只眼)合并晶状体后囊破裂的眼内异物患者实施白内障联合玻璃体视网膜手术.其中周边视网膜格子样变性39只眼,视网膜裂孔者7只眼,玻璃体积血30只眼,视网膜脱离7只眼,锯齿缘解离2只眼.实施白内障摘除、玻璃体切除、视网膜光凝、人工晶状体植入、眼内注气术,术中显微镜下眼外导光照明、视网膜激光光凝联合前房注气.术后观察视力、人工晶状体、视网膜情况及并发症.术后随访6~11个月,平均(6.14±2.15)月.结果 47例患者中,42只眼充填C3F8,5只眼充填硅油.44只眼视力不同程度改善.41只眼人工晶状体正位,1只眼人工晶状体略偏斜.3只眼发生孔源性视网膜脱离.8只眼继发性青光眼,药物治疗1周至2周眼压恢复正常.2只眼角膜内皮面增生膜生长.结论 显微镜下眼外导光照明、视网膜激光光凝联合前房注气在白内障联合玻璃体视网膜手术中操作方便,安全可靠,减少了手术并发症发生,有很好的实用价值.此术式是白内障玻璃体视网膜联合手术的有力补充.%Objective To study the clinical efficacy and feasibility associated with microscopically eye light illumination,retinal laser photocoagulation combined with gas anterior chamber tamponade in the cataract joint vitreoretinal surgery.Methods It was a retrospective analysis of 47 cases (47 eyes) with intraocular foreign bodies and lens capsule rupture was performed cataract joint vitreoretinal surgery.Among 47 cases,peripheral lattice retinal degeneration in 39 eyes,peripheral retinal tear in 7 eyes,vitreous hemorrhage in 30 eyes,retinal detachment in 7 eyes,retinal serrated edge disintegrate in 2 eyes.The patients were performed cataract

  14. Anterior Eye Imaging with Optical Coherence Tomography

    Science.gov (United States)

    Huang, David; Li, Yan; Tang, Maolong

    The development of corneal and anterior segment optical coherence tomography (OCT) technology has advanced rapidly in recently years. The scan geometry and imaging wavelength are both important choices to make in designing anterior segment OCT systems. Rectangular scan geometry offers the least image distortion and is now used in most anterior OCT systems. The wavelength of OCT light source affects resolution and penetration. An optimal choice of the OCT imaging wavelength (840, 1,050, or 1,310 nm) depends on the application of interest. Newer generation Fourier-domain OCT technology can provide scan speed 100-1000 times faster than the time-domain technology. Various commercial anterior OCT systems are available on the market. A wide spectrum of diagnostic and surgical applications using anterior segment OCT had been investigated, including mapping of corneal and epithelial thicknesses, keratoconus screening, measuring corneal refractive power, corneal surgery planning and evaluation in LASIK, intracorneal ring implantation, assessment of angle closure glaucoma, anterior chamber biometry and intraocular lens implants, intraocular lens power calculation, and eye bank donor cornea screening.

  15. 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

  16. The Bern Infinitesimal Bubble Chamber (BIBC)

    CERN Multimedia

    1977-01-01

    The chamber body was machined from a block of aluminium. The visible volume was cylindrical with 65 mm diameter and 35 mm depth. It was filled with propane or freon. It was meant as vertex detector in the search of short-lived particles. It was also used with in-line holography resulting in 8 µm bubble size and 9 cm depth of the field. See E. Ramseyer, B. Hahn and E. Hugentobler, Nucl. Instrum. Methods 201 (1982) 335.

  17. 应用锥形束CT探究上颌前牙区颌骨微种植支抗钉植入的安全区%Quantitative study of maxillary anterior bone depth and labial cortical bone thickness for micro- implant anchorage placement using cone beam CT

    Institute of Scientific and Technical Information of China (English)

    赵岩; 吴平

    2012-01-01

    目的:对上颌前牙区颌骨的骨量及唇侧骨皮质厚度进行测量分析,为正畸治疗植入微种植支抗钉的安全区提供参考.方法:对25例成人患者上颌前牙区行锥形束CT扫描及三维重建,测量距上颌牙槽嵴顶3、6、9、12mm水平上颌中切牙、侧切牙、尖牙根间区近远中向、唇腭向的距离以及唇侧骨皮质厚度.结果:在距上颌牙槽嵴顶3、6、9mm水平中切牙根间近远中向距离均最宽,唇侧骨皮质均最薄;在距牙槽嵴顶9mm水平中切牙与侧切牙根间近远中向距离最窄;在4个测量水平侧切牙与尖牙根间唇侧骨皮质均最厚;唇腭向在距牙槽嵴顶9mm及以上水平,中切牙根间骨厚度最薄,中切牙与侧切牙根间骨厚度最厚.25例中仅3例前牙区各牙根长度超过12mm,在距牙槽嵴顶12mm水平测出的根间近远中向距离均较宽.结论:通过对扫描后颌骨影像的分析,明确了前牙区颌骨的骨量及唇侧骨皮质厚度,为植入微种植支抗钉的安全区提供参考.%Objective: To investigate the bone depth and labial cortical bone thickness of maxillary anterior interdental area for orthodontic micro-implant anchorage. Methods; Maxillary anterior alveolar bone of 25 adults was scanned and reconstructed by cone beam CT, the mesio-distal interdental distance, labial-palatal bone depth and labial cortical bone thickness were measured at 3, 6, 9 and 12 mm from the alveolar crest between upper anterior dental roots. Results; The mesio-distal distance between central incisors was the widest in all measurement levels, while the labial cortical bone thickness was the thinnest. At the 9 mm-level, the shortest mesio-distal distance was between the roots of central and lateral incisors. The labial cortical bone thickness between lateral incisors and canines was the thickest in all measurement levels. At or above the 9 mm-level, the labial-palatal bone depth was the thinnest between central incisors, but the thickest

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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...

  3. 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...

  4. Evaluation of Anterior Segment Parameter Changes Using the Sirius after Uneventful Phacoemulsification

    Science.gov (United States)

    Şimşek, Ali; Çapkın, Musa; Bilak, Şemsettin; Güler, Mete; Reyhan, Ali Hakim

    2016-01-01

    Purpose To investigate changes in anterior chamber depth (ACD), corneal volume (CV), anterior chamber angle (ACA), anterior chamber volume (ACV), central corneal thickness (CCT), horizontal visible iris diameter (HVID), pupil diameter (PD), and intraocular pressure (IOP) after uneventful phacoemulsification cataract surgery with intraocular lens implantation. Methods A total of 132 eyes of 132 patients (87 men and 45 women) that underwent uneventful phacoemulsification cataract surgery and intraocular lens implantation were prospectively studied. The mean age of the patients was 63.68 ± 12.51 years. All patients were evaluated preoperatively and at 1 month postoperatively with the Sirius 3D Rotating Scheimpflug camera topography system. The ACD, CV, ACA, ACV, CCT, HVID, and PD measurements were recorded. IOP was measured using the Goldmann applanation tonometer, which was corrected for CCT of the Sirius device using Ehlers' formula. Results The preoperative mean ACD, ACV, ACA, CCT, CV, PD, HVID, and IOP were 2.79 ± 0.45 mm, 124.73 ± 25.72 mm3, 42.09 ± 7.490, 523.87 ± 41.97 microns, 55.37 ± 4.89 mm3, 3.98 ± 1.23 mm, 11.72 ± 0.67 mm, and 14.74 ± 2.59 mmHg, respectively. Three months postoperatively, the mean ACD, ACV, ACA, CCT, CV, PD, HVID, and IOP were 3.45 ± 0.6 mm, 162.52 ± 23.79 mm3, 51.46 ± 5.630, 526.21 ± 44.45 microns, 56.23 ± 5.12 mm3, 2.87 ± 0.45 mm, 11.91 ± 0.75 mm, and 12.02 ± 1.83 mmHg, respectively. There was a statistically significant increase in mean postoperative ACD, ACV, ACA, CV, and HVID compared with the corresponding preoperative values (p < 0.05). CCT remained stable after surgery. Postoperative PD and IOP were significantly decreased compared to corresponding preoperative values (p < 0.05). Conclusions Preoperative measurements by the Sirius 3D Rotating Scheimpflug camera topography system might help surgeons to predict postoperative changes resulting from phacoemulsification and intraocular lens implantation. This is a

  5. Posterior Chamber Hemorrhage during Fluorescein Angiography

    Directory of Open Access Journals (Sweden)

    Manuel A. P. Vilela

    2015-01-01

    Full Text Available This paper provides the first reported case of acute posterior chamber hemorrhage during fluorescein angiography (FA. This is a case review with serial color photographs of the anterior segment. A 76-year-old male was referred for angiographic control of age-related macular degeneration. He was pseudophakic OU, BCVA 20/40 OU. He had mild hypertension, but not diabetes. He had had two previous angiograms without adverse effects. Difficulty was experienced in obtaining the images owing to a progressive reduction in the transparency of the media. A dense hemorrhage in the posterior chamber of the right eye was found, involving the visual axis. Thorough biomicroscopy, gonioscopy, and ultrasonic biomicroscopy showed that part of one of the haptics of the right intraocular lens (IOL was touching and tearing the posterior face of the iris, without any visible synechiae, iris, or angle neovascularization. Anterior segment FA and posterior ultrasonography were normal. No similar case has been described in the literature involving dense progressive bleeding located in the capsular bag and posterior chamber, without any detectable triggering ocular event other than mydriasis and fluorescein injection. Contact of the iris or sulcus with part of the intraocular lens, aggravated by the intense use of mydriatics during the FA procedure, probably caused bleeding to happen.

  6. CHAMBER OF COMMERCE INFORMATION

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Experience Japan The Japanese Chamber of Commerce and Industry will further promote its Japan-experience program and seek cooperation with various Chinese institutions.Between early May and June 2007,the chamber organized a Chinese college student delegation to Japan with the support from its members in China.

  7. Target chambers for gammashpere

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, M.P.; Falout, J.W.; Nardi, B.G. [and others

    1995-08-01

    One of our responsibilities for Gammasphere, was designing and constructing two target chambers and associated beamlines to be used with the spectrometer. The first chamber was used with the early implementation phase of Gammasphere, and consisted of two spun-Al hemispheres welded together giving a wall thickness of 0.063 inches and a diameter of 12 inches.

  8. BEBC bubble chamber

    CERN Multimedia

    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. Fluidized bed combustion chamber

    Energy Technology Data Exchange (ETDEWEB)

    Kullendorff, A.; Wikner, J.

    1985-03-25

    The chamber is confined in a pressure vessel. The lower part of the chamber has tilted parallel gutters up to the height of the fluidized bed. The slope of the gutter walls is 5 degrees-15 degrees and the top area of the gutters is 1.3 to 3 times larger than their bottom.

  11. DELPHI time projection chamber

    CERN Multimedia

    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.

  12. 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

  13. PS wire chamber

    CERN Multimedia

    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.

  14. Anterior Cruciate Ligament (ACL) Injuries

    Science.gov (United States)

    ... Week of Healthy Breakfasts Shyness Anterior Cruciate Ligament (ACL) Injuries KidsHealth > For Teens > Anterior Cruciate Ligament (ACL) ... and Recovery Coping With an ACL Injury About ACL Injuries A torn anterior cruciate ligament (ACL) is ...

  15. 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

  16. 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.

  17. 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).

  18. High rate drift chambers

    Energy Technology Data Exchange (ETDEWEB)

    Christian, D.C. (Fermilab, Batavia, IL 60510 (United States)); Berisso, M.C. (Fermilab, Batavia, IL 60510 (United States)); Gutierrez, G. (Fermilab, Batavia, IL 60510 (United States)); Holmes, S.D. (Fermilab, Batavia, IL 60510 (United States)); Wehmann, A. (Fermilab, Batavia, IL 60510 (United States)); Avilez, C. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Felix, J. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Moreno, G. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Romero, M. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Sosa, M. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Forbush, M. (Department of Physics, Texas A and M University, College Station, TX 77843 (United States)); Huson, F.R. (Department of Physics, Texas A and M University, College Station, TX 77843 (United States)); Wightman, J.A. (Department of Physi

    1994-06-01

    Fermilab experiment 690, a study of target dissociation reactions pp[yields]pX using an 800 GeV/c proton beam and a liquid hydrogen target, collected data in late 1991. The incident beam and 600-800 GeV/c scattered protons were measured using a system of six 6 in.x4 in. and two 15 in.x8 in. pressurized drift chambers spaced over 260 m. These chambers provided precise measurements at rates above 10 MHz (2 MHz per cm of sense wire). The measurement resolution of the smaller chambers was 90 [mu]m, and the resolution of the larger chambers was 125 [mu]m. Construction details and performance results, including radiation damage, are presented. ((orig.))

  19. Toxic Test Chambers

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Hazardous material test facility Both facilities have 16,000 cubic foot chambers, equipped with 5000 CFM CBR filter systems with an air change...

  20. 前房放液治疗有晶状体眼后房型人工晶状体植入术后高眼压%Releasing aqueous humor of anterior chamber to treat early elevated lOP after lCL implantation

    Institute of Scientific and Technical Information of China (English)

    熊露; 易魁先; 邓一鹏; 彭晓琍

    2015-01-01

    目的::探讨前房放液法在有晶状体眼后房型人工晶状体植入术( implantable collamer lens,ICL)术后早期眼压升高治疗中的应用。方法:ICL植入术后早期高眼压患者,眼压>25 mmHg时,表面麻醉下,用一次性注射器针尖从角膜侧切口缓慢将房水放出,使眼压降至10~13 mmHg。术后每2 h测量眼压,如眼压再次升高,可反复放房水处理,直至眼压正常。结果:ICL植入术患者167例330眼,术后眼压>25 mmHg者32例62眼,其中部分房水可见黏弹剂。大多数患眼(48眼)通过1次放液治疗成功无复发。经过最多3次侧切口放液,所有患眼眼压均恢复正常。术后随访未见异常。结论:黏弹剂残留是导致ICL植入术后早期眼压升高的主要原因,侧切口前房放液法能有效、及时降低眼压。操作简单、安全、无痛,患者乐于接受,可反复进行。%To explore the effect of releasing aqueous humor of anterior chamber through lateral incision of cornea in treating early elevated intraocular pressure ( lOP ) after implantation of implantable collamer lens ( lCL) .METHODS: Patients with elevated lOP were analyzed after lCL implantation. When the lOP>25mmHg, aqueous humor was released slowly through lateral incision of cornea, and made the lOP reduce to 10 ~13mmHg. After operation, lOP was measured every 2h. The releasing of aqueous humor was repeated until the lOP was decreased to normal.RESULTS: One hundred sixty - seven patients ( 330 eyes) were implanted lCL, while the lOP of 32 patients (62 eyes) was higher than 25mmHg after lCL implantation. Viscoelastic material was found in aqueous humor of most of high lOP patients, and the lOP of 48 eyes did not increase again through releasing aqueous humor once. The lOP of all these eyes was decreased to normal through releasing aqueous humor in 3 times at most. There were no abnormal in postoperative follow-up.CONCLUSlON:The main reason of early elevated lOP after lCL implantation

  1. 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.

  2. Anterior cervical plating

    Directory of Open Access Journals (Sweden)

    Gonugunta V

    2005-01-01

    Full Text Available Although anterior cervical instrumentation was initially used in cervical trauma, because of obvious benefits, indications for its use have been expanded over time to degenerative cases as well as tumor and infection of the cervical spine. Along with a threefold increase in incidence of cervical fusion surgery, implant designs have evolved over the last three decades. Observation of graft subsidence and phenomenon of stress shielding led to the development of the new generation dynamic anterior cervical plating systems. Anterior cervical plating does not conclusively improve clinical outcome of the patients, but certainly enhances the efficacy of autograft and allograft fusion and lessens the rate of pseudoarthrosis and kyphosis after multilevel discectomy and fusions. A review of biomechanics, surgical technique, indications, complications and results of various anterior cervical plating systems is presented here to enable clinicians to select the appropriate construct design.

  3. THERAPY OF FIBRINOUS PLASTIC ANTERIOR UVEITIS

    Directory of Open Access Journals (Sweden)

    A. L. Onishchenko

    2015-01-01

    Full Text Available Aim. To analyze the efficacy of modified pupillary massage technique using cycloplegic agent Appamide Plus in the treatment of anterior uveitis. Patients and methods. 45 patients (25 men and 20 women aged 21‑69 with endogenous uveitis (51 eyes were enrolled in the study. Etiology of uveitis was identified in 57.7 % of cases: herpes simplex virus (22.2 %; systemic disorders — rheumatoid arthritis, Reiter syndrome, Bechterew’s disease, psoriasis (17.7 %; local infection — purulent periodontitis or sinusitis (11 %. Patients were divided into two groups. Group I received basic therapy in combination with traditional pupillary massage. Group II received basic therapy in combination with modified pupillary massage using Appamide Plus (muscarinic receptor antagonist and alpha adrenergic agonist and plasma exchange with cell mass ozonation. Results. Inflammation of the uveal tract was prevented in all patients. In group I (traditional pupil massage, posterior synechiae persisted in 26 % of cases. In group II (pupil massage using Appamide Plus, anterior chamber humor was transparent, posterior synechiae were broken, normal pupillary response was re-established. Additionally, inflammatory exudate in the anterior chamber and endothelial precipitates resolved by 3.3 days earlier than in group I (р < 0.05. Visual outcomes were also better in Appamide Plus group. T cell-mediated immunity study revealed initial CD3+ cell and T cell subpopulation deficiency. Relative and absolute references of T cells and their subpopulations tended to decrease even when uveitis signs reduced. Conclusions. T cell-mediated immunity depression is probably due to pharmacotherapy. Appamide Plus eye drops are highly effective for therapeutic mydriasis and pupillary massage in the course of anterior uveitis treatment to prevent synechiae formation in enlarged or small pupil.

  4. The long-term anterior segment configuration after pediatric cataract surgery and the association with secondary glaucoma

    Science.gov (United States)

    Chen, Ding; Gong, Xian-hui; Xie, He; Zhu, Xue-ning; Li, Jin; Zhao, Yun-e

    2017-01-01

    Secondary glaucoma constitutes major sight-threatening complication of pediatric cataract surgery, yet the etiology remains unclear. The purpose of this study was to investigate the long-term anterior segment configuration and the association with secondary glaucoma in pediatric pseudophakia. Ultrasound biomicroscopy (UBM) was performed on 40 eyes of 26 children underwent pediatric cataract surgery and intraocular lens (IOL) implantation. The anterior chamber depth (ACD), angle-opening distance at 500 μm (AOD500), trabecular-iris angle (TIA), central corneal thickness (CCT), structural abnormities, IOL position, IOP, and incidence of glaucoma were evaluated. High insertion of iris, in which the iris root is attached more anteriorly than normal, was seen in 13 eyes (32.50%). IOL was located in the capsular bag in 19 eyes and in the ciliary sulcus in 21 eyes. Logistic regression analysis identified high insertion of iris (OR 3.40, 95% CI 1.03–11.17, p = 0.03) and IOL implantation in sulcus (OR 1.39, 95% CI 1.07–4.85, p = 0.04) as independent risk factors for glaucoma. The presence of high insertion of iris and IOL implantation in ciliary sulcus may increase the long-term risk of the development of secondary glaucoma after pediatric cataract surgery. PMID:28220849

  5. Responses of the Ocular Anterior Segment and Refraction to 0.5% Tropicamide in Chinese School-Aged Children of Myopia, Emmetropia, and Hyperopia

    Directory of Open Access Journals (Sweden)

    Ying Yuan

    2015-01-01

    Full Text Available Purpose. To investigate the changes of anterior segment after cycloplegia and estimate the association of such changes with the changes of refraction in Chinese school-aged children of myopia, emmetropia, and hyperopia. Methods. 309 children were recruited and eligible subjects were assigned to three groups: hyperopia, emmetropia, or myopia. Cycloplegia was achieved with five cycles of 0.5% tropicamide. The Pentacam system was used to measure the parameters of interest before and after cycloplegia. Results. In the myopic group, the lenses were thinner and the lens position was significantly more posterior than that of the emmetropic and hyperopic groups in the cycloplegic status. The correlations between refraction and lens thickness (age adjusted; r=0.26, P<0.01, and lens position (age adjusted; r=-0.31, P<0.01 were found. After cycloplegia, ACD and ACV significantly increased, while ACA significantly decreased. Changes in refraction, ACD, ACV, and ACA were significantly different among the three groups (P<0.05, all. Changes of refraction were correlated with changes of ACD (r=0.41, P<0.01. Conclusions. Myopia presented thinner lenses and smaller changes of anterior segment and refraction after cycloplegia when compared to emmetropia and hyperopia. Changes of anterior chamber depth were correlated with refraction changes. This may contribute to a better understanding of the relationship between anterior segment and myopia.

  6. Pseudophakic hyperopia in nanophthalmic eyes managed by a posterior chamber implantable collamer lens

    Directory of Open Access Journals (Sweden)

    Kothari Kulin

    2011-01-01

    Full Text Available We report a case of a bilateral posterior chamber implantable collamer lens (ICL implantation post-clear lens extraction, to reduce the residual hyperopia, in a patient with nanophthalmic eyes. A 30-year-old female patient, keen to reduce her dependency on glasses and contact lenses, came to our refractive surgery department. Her refractive error was +12.0 and +12.5 diopters in the right and left eye, respectively, with steep corneas on keratometry and a shallow anterior chamber depth. She underwent clear lens extraction with implantation of +35.0 D and +40.0 D IOL in the right eye and left eye, respectively. Her post-operative best-corrected visual acuity was 20/30 with +8.5 D in the right eye and +6 D in the left. She underwent bilateral ICL implantation. Postoperatively after 6 months, her unaided visual acuity was 20/30 in both eyes. In conclusion, ICL implantation can be considered to correct residual hypermetropic ametropia in pseudophakic eyes when other options have limitations.

  7. Prevalence of Corneal Astigmatism and Anterior Segmental Biometry Characteristics Before Surgery in Chinese Congenital Cataract Patients.

    Science.gov (United States)

    Lin, Duoru; Chen, Jingjing; Liu, Zhenzhen; Wu, Xiaohang; Long, Erping; Luo, Lixia; Lin, Zhuoling; Li, Xiaoyan; Zhang, Li; Chen, Hui; Liu, Jinchao; Chen, Weirong; Lin, Haotian; Liu, Yizhi

    2016-02-25

    The prevalence and the distribution characteristics of corneal astigmatism (CA) and anterior segment biometry before surgery in Chinese congenital cataract (CC) patients are not completely understood. This study involved 400 CC patients from the Zhongshan Ophthalmic Center enrolled from February 2011 to August 2015. Data on CA, keratometry, central corneal thickness (CCT) and anterior chamber depth (ACD) were measured by the Pentacam Scheimpflug System. The mean age of patients was 54.27 months, and the ratio of boys to girls was 1.53:1. The mean CA was 2.03 diopters (D), and 39.25% of subjects had CA values ≥2 D. The most frequent (71.8%) diagnosis was with-the-rule astigmatism. Oblique astigmatism was present in 16.2% of cases, and 12% of cases had against-the-rule astigmatism. The mean keratometry measurement of cataractous eyes in bilateral patients was significantly larger than that in unilateral patients. Girls had a larger mean keratometry but a thinner CCT than did boys. The CA, CCT, and ACD of cataractous eyes were significantly larger than those of non-cataractous eyes in unilateral patients. The CA, mean keratometry, CCT, and ACD in CC patients varied with age, gender, and laterality. Fully understanding these characteristics may help inform guidelines and treatment decisions in CC patients.

  8. 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.

  9. The KLOE drift chamber

    Energy Technology Data Exchange (ETDEWEB)

    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. E-mail: paolo.valente@lnf.infn.it; Valeriani, B.; Venanzoni, G.; Veneziano, S.; Wu, Y.; Xie, Y.G.; Zhao, P.P.; Zhou, Y

    2001-04-01

    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.

  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. Charpak hemispherical wire chamber

    CERN Multimedia

    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.

  12. 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.

  13. 白内障超声乳化摘出术后OCT测量的眼前节结构改变%The changes of ocular anterior segment configuration following phacoemulsification determined by anterior segment OCT

    Institute of Scientific and Technical Information of China (English)

    郑虔

    2016-01-01

    Cataract is a main blinding eye disease worldwide,follwed by glaucoma.Expension of lens volume occurs in early stage of age-related cataractous eyes,which is a risk factor of Primary angle-closure glaucoma,and phacoemulsification is a feasible approach to remove it.However,how to select the timing of operation and determine the prognosis is the major challenge for ophthalmologists.In order to evaluate the influence of phacoemulsification on ocular anterior segment configuration,we collected the information of 17 articles that quantitatively analyzed the ocular anterior segment parameter changes after phacoemulsification,determined by anterior segment OCT (AS-OCT).Total 866 eyes that received phacoemulsification for age-related cataract were included in the following-up duration for 6 months,and the results showed that the mean anterior chamber depth (ACD),anterior chamber volume (ACV),anterior chamber angle (ACA),angle opening distance 500 μm anterior to the scleral spur (AODS00),angle opening distance 750 μm anterior to the scleral spur (AOD750),trabecular-iris space area 500 μm from scleral spur (TISA500),trabecular-iris space area 750 μm from scleral spur(TISA750),and angle recess area 750 μm anterior to the scleral spur (ARA 750) were increased,but the mean anterior chamber width (ACW) and iris thickness measured at 750 μm (IT750) were not significantly changed,while the postoperative iris curvature (I-Curv),iris cross-sectional area and convex hull of iris segments were decreased after phacoemulsification.In addition,the postoperative ACD,TISA500 showed positive correlations to preoperative lens thickness,and the ACD and AOD500 in 3 months after operation were positively correlated to the preoperative lens value (LV).This systematic review concluded that phacoemulsification could be used for the treatment of glaucoma by relieving pupillary block,reducing the iris oppression,deepening the anterior chamber and opening anterior chamber angle.%目前,白内

  14. LEP vacuum chamber, prototype

    CERN Multimedia

    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.

  15. 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.

  16. 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.

  17. OPAL Muon Chamber

    CERN Multimedia

    OPAL was one of the 4 experiments installed at the LEP particle accelerator from 1989 to 2000. This is a slice of the outermost layer of OPAL : the muon chambers. This outside layer detects particles which are not stopped by the previous layers. These are mostly muons.

  18. 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.

  19. Heavy liquid bubble chamber

    CERN Multimedia

    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.

  20. Secondary emission gas chamber

    CERN Document Server

    In'shakov, V; Skvortsov, V

    2014-01-01

    For a hadron calorimeter active element there is considered a gaseous secondary emis-sion detector (150 micron gap, 50 kV/cm). Such one-stage parallel plate chamber must be a radiation hard, fast and simple. A model of such detector has been produced, tested and some characteristics are presented.

  1. Comparison of anterior segment parameters with pentacam according to age in emmetropic eyes

    Directory of Open Access Journals (Sweden)

    Yasin Çınar

    2013-12-01

    Full Text Available Objective: It was aimed to compare anterior segment parametersobtained by rotating Scheimpflug camera systemaccording to age groups.Methods: 290 eyes of 145 emmetropic subjects wereincluded in the study. Subjects were divided in threeage groups. Group 1 comprised the subjects age up to20 years, Group 2 comprised the subjects age between21 and 40 and Group 3 comprised the subjects between41 years and older. In all subjects, flat keratometry (K1,steep keratometry (K2, mean corneal power (Km,maximum keratometry (Kmax, central corneal thickness(CCT, apex corneal thickness (ACT, thinnest cornealthickness (TCT, anterior chamber volume (ACV and anteriorchamber depth (ACD were obtained by using rotatingScheimpflug camera system. To eliminate operatordependent variables, automatic release mode was used.All measurements were obtained by the same examiner.Results: The study included 72 female and 73 male subjects.The mean age of the subjects was 31.37±12.29years (range, 8-65. There were no significant differencesin keratometric values between age groups. Therewas significant difference between Groups 1 and 3 andGroups 2 and 3 in the mean CCT, ACT and TCT (p<0.05.There was significant difference between the groups inthe mean ACD and ACV. There significant positive correlationbetween age and CCT (r=0.181, p=0.001, ACT(r=0.161, p=0.006 and TCT (r=0.16, p=0.006. Therewere significant negative correlations between age andACD (r=-0.376, p<0.001 and ACV (r=-0.367, p<0.001.Conclusion: In the emmetropic eyes, significant reductionwas found in ACD and ACV, while there was significantincrease in CCT, ACT and TCT by age.Key words: Corneal topography, anterior segment, emetropic eyes, pentacam

  2. Anterior crucate ligament (ACL) injury

    Science.gov (United States)

    ... An anterior cruciate ligament injury is the over-stretching or tearing of the anterior cruciate ligament (ACL) ... may be injured. This is a medical emergency. Prevention Use proper techniques when playing sports or exercising. ...

  3. Evaluation of anterior segment parameters and possible influencing factors in normal subjects using a dual Scheimpflug analyzer.

    Directory of Open Access Journals (Sweden)

    Xiaogang Wang

    Full Text Available PURPOSE: To investigate normal anterior segment parameters and analyze the possible influencing factors using a dual Scheimpflug system. SETTING: Department of Ophthalmology, Affiliated Sixth People's Hospital Shanghai Jiao Tong University, Shanghai, China. DESIGN: A prospective observational case series. METHODS: A total of 153 normal subjects (153 eyes were studied. The anterior segment parameters, including the central corneal thickness (CCT, anterior chamber depth (ACD, pupil diameter (PD, keratoconus prediction index (KPI, simulated keratometry (SimK values, anterior instantaneous curvature (AIC, posterior axial curvature (PAC, corneal eccentricity, total corneal power (TCP, axial curvature (AC, total corneal wavefront (TCW, high order aberration (HOA, and spherical aberration (SA, were determined using a dual Scheimpflug analyzer. RESULTS: The CCT and ACD were both negatively correlated with age (r = -0.203, p = 0.012; r = -0.589, p<0.001. There was no significant difference in the refractive indices of AIC and SimK. Compared with the negative correlation of HOA and SA (r = -0.358, p<0.001, a positive correlation was found between TCW and HOA (r = 0.561, p<0.001. Unlike the decreased tendency of AC, the TCP increased gradually from the center to the periphery in the central 8 mm diameter. TCP showed a significant correlation with AC in the analyzed area. CONCLUSIONS: AIC and SimK provide different information in clinic, but the refractive indices of them showed no difference in this healthy study population, and age should be considered when using CCT and ACD values.

  4. Age-Related Change and Gender Difference in Ocular Anterior Segment Parameters%眼前段生物结构参数的年龄相关性改变与性别差异研究

    Institute of Scientific and Technical Information of China (English)

    苏鹏; 孔祥斌; 晏世刚; 黄玉娟

    2016-01-01

    目的:比较30岁以上正常人不同年龄段眼前段生物结构参数的变化及性别差异,为闭角型青光眼的发病机制提供证据。方法选择474例眼科门诊检查正常者为研究对象,均30岁以上,其中男213例,女261例。采用眼前段光学相干断层扫描仪,获取眼前段水平图像,用中山房角分析软件进行图片分析获得眼前段结构参数[包括房角宽度(angle open distance,AOD500)、虹膜面积、前房深度及前房容积],按年龄、性别进行分组,采用 stata12.0进行数据处理及分析。结果各年龄段 AOD500、前房深度、前房容积及虹膜面积比较差异均有统计学意义(P <0.001);男性 AOD500、前房深度、前房容积及虹膜面积均显著高于女性(P <0.001)。30~55岁年龄段,AOD500变化最大,而55岁后 AOD500变化相对平缓;男性前房容积在50岁前变化相对明显,50岁后变化相对平缓,而女性前房容积变化明显且均匀。结论30以上正常人 AOD500、前房深度、前房容积均随年龄增加呈递减趋势,而虹膜面积随年龄增加呈递增趋势;女性较男性更易患闭角型青光眼。%Objective To investigate the age-related change and gender difference in ocular an-terior segment parameters in persons older than 30 years,and to provide evidence for the patho-genesis of angle-closure glaucoma.Methods A total of 474 normal subjects older than 30 years (213 males and 261 females)were selected in this study.The anterior segment optical coherence tomography(AS-OCT)was performed to obtain the anterior segment images,and the Zhongshan Angle Assessment Program was used to obtain the ocular anterior segment parameters,including angle opening distance at 500 μm(AOD500),iris area,anterior chamber depth and anterior cham-ber volume.These subjects were divided into different age and gender groups.Data were analyzed using Stata12.0.Results There were significant

  5. Anechoic Radio Frequency Test Chamber

    Data.gov (United States)

    Federal Laboratory Consortium — This chamber is used for characterization test of such systems as communications gear, tanks, radar, missiles, and helicopters. The dimensions of the chamber are 114...

  6. Anterior segment intraocular metallic foreign body causing chronic hypopyon uveitis

    OpenAIRE

    Mete, Güler; Turgut, Yılmaz; Osman, Arslanhan; Gülşen, Ülkü; Hakan, Artaş

    2010-01-01

    Intraocular foreign body (IOFB) is a common association of penetrating ocular trauma. Early diagnosis and removal of IOFBs especially if they are metallic is very important to determine further management and the final result of treatment. Missed IOFB may present in different clinical aspects that may limit its detection and symptoms may only become apparent after a prolonged period of time. We report a case of a missed metallic intraocular foreign body in the anterior chamber over a 2-year p...

  7. Facetas em dentes anteriores

    OpenAIRE

    Veloso, Helena Rafaela Lourenço Martins

    2015-01-01

    Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária A presente revisão bibliográfica aborda as facetas estéticas em dentes anteriores, pela crescente valorização de um sorriso esteticamente agradável, facto que faz com que as pessoas procurem cada vez mais alternativas de tratamento para melhorar a aparência do seu sorriso. Os dentes anteriores são decisivos na aparência estética e, c...

  8. Intradural anterior transpetrosal approach.

    Science.gov (United States)

    Ichimura, Shinya; Hori, Satoshi; Hecht, Nils; Czabanka, Marcus; Vajkoczy, Peter

    2016-10-01

    The standard anterior transpetrosal approach (ATPA) for petroclival lesions is fundamentally an epidural approach and has been practiced for many decades quite successfully. However, this approach has some disadvantages, such as epidural venous bleeding around foramen ovale. We describe here our experience with a modified technique for anterior petrosectomy via an intradural approach that overcomes these disadvantages. Five patients with petroclival lesions underwent surgery via the intradural ATPA. The intraoperative hallmarks are detailed, and surgical results are reported. Total removal of the lesions was achieved in two patients with petroclival meningioma and two patients with pontine cavernoma, whereas subtotal removal was achieved in one patient with petroclival meningioma without significant morbidity. No patient experienced cerebrospinal fluid leakage. The intradural approach is allowed to tailor the extent of anterior petrosectomy to the individually required exposure, and the surgical procedure appeared to be more straightforward than via the epidural route. Caveats encountered with the approach were the temporal basal veins that could be spared as well as identification of the petrous apex due to the lack of familial epidural landmarks. The risk of injury to the temporal bridging veins is higher in this approach than in the epidural approach. Intradural approach is recommended in patients with a large epidural venous route, such as sphenobasal and sphenopetrosal vein. Navigation via bone-window computed tomography is useful to identify the petrous apex.

  9. 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.

  10. Multi-anode ionization chamber

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov, Aleksey E. (South Setauket, NY); Smith, Graham (Port Jefferson, NY); Mahler, George J. (Rocky Point, NY); Vanier, Peter E. (Setauket, NY)

    2010-12-28

    The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.

  11. Misdiagnosis induced intraocular lens dislocation in anterior megalophthalmos

    Institute of Scientific and Technical Information of China (English)

    WANG Qi-wei; XU Wen; ZHU Ya-nan; LI Jin-yu; ZHANG Li; YAO Ke

    2012-01-01

    Anterior megalophthalmos (AM) is an uncommon developmental anomaly of the anterior segment of the eye with a constellation of findings that includes enlarged cornea,deep anterior chamber,posterior positioning of the iris and lens,iris stroma atrophy,hypoplasia of iris dilator,pupil displacement,large capsular bag,lens subluxation,prematurely cataract and the tendency to retinal detachment.AM,especially when symptoms are mild,is not an easy disease to diagnose.We present 3 AM cases that were misdiagnosed as congenital cataract with weak zonule and megalocornea.Intraocular lenses (IOLs) dislocated after standard cataract surgeries and subsequent surgery (replacing the dislocated IOLs with iris-claw intraocular lenses) achieved satisfactory outcome.Although rare,AM should be included in the differential diagnosis of enlarged cornea and we recommend implanting Artisan lens in AM patients.

  12. Effect of acupuncture depth on muscle pain

    Directory of Open Access Journals (Sweden)

    Kitakoji Hiroshi

    2011-06-01

    Full Text Available Abstract Background While evidence supports efficacy of acupuncture and/or dry needling in treating musculoskeletal pain, it is unclear which needling method is most effective. This study aims to determine the effects of depth of needle penetration on muscle pain. Methods A total of 22 healthy volunteers performed repeated eccentric contractions to induce muscle soreness in their extensor digital muscle. Subjects were assigned randomly to four groups, namely control group, skin group (depth of 3 mm: the extensor digital muscle, muscle group (depth of 10 mm: the extensor digital muscle and non-segmental group (depth of 10 mm: the anterior tibial muscle. Pressure pain threshold and electrical pain threshold of the skin, fascia and muscle were measured at a point 20 mm distal to the maximum tender point on the second day after the exercise. Results Pressure pain thresholds of skin group (depth of 3 mm: the extensor digital muscle and muscle group (depth of 10 mm: the extensor digital muscle were significantly higher than the control group, whereas the electrical pain threshold at fascia of muscle group (depth of 10 mm: the extensor digital muscle was a significantly higher than control group; however, there was no significant difference between the control and other groups. Conclusion The present study shows that acupuncture stimulation of muscle increases the PPT and EPT of fascia. The depth of needle penetration is important for the relief of muscle pain.

  13. The APS ceramic chambers

    Energy Technology Data Exchange (ETDEWEB)

    Milton, S.; Warner, D.

    1994-07-01

    Ceramics chambers are used in the Advanced Photon Source (APS) machines at the locations of the pulsed kicker and bumper magnets. The ceramic will be coated internally with a resistive paste. The resistance is chosen to allow the low frequency pulsed magnet field to penetrate but not the high frequency components of the circulating beam. Another design goal was to keep the power density experienced by the resistive coating to a minimum. These ceramics, their associated hardware, the coating process, and our recent experiences with them are described.

  14. 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.

  15. Assessment of Anterior Segment Changes in Pseudophakic Eyes, Using Ultrasonic Biomicroscopic Imaging, after Pars Plana Vitrectomy with Silicone Oil or Gas Tamponade.

    Science.gov (United States)

    Ünsal, Erkan; Eltutar, Kadir; Karini, Belma; Kızılay, Osman

    2016-01-01

    Objective. To evaluate the morphological changes of the anterior segment using ultrasonic biomicroscopy (UBM) imaging in pseudophakic patients who underwent pars plana vitrectomy (PPV) with silicone oil or gas (C3F8) internal tamponade agent injection. Method. This prospective study included pseudophakic patients with planned PPV, divided into two groups according to internal tamponade agent: those in which silicone oil was used (n = 27, Group 1) and those in which gas (C3F8) was used (n = 24, Group 2). UBM measurements were performed in the supine position before and one week after surgery. Results. In patients of Group 1, postoperative trabecular meshwork-ciliary process distance (T-CPD) and iris-ciliary process distance (I-CPD), according to preoperative values, were found to be statistically significantly reduced, and postoperative mean value of scleral thickness (ST) and intraocular pressure (IOP), according to preoperative value, was found to be statistically significantly increased. In patients of Group 2, postoperative mean values of anterior chamber depth (ACD), ciliary body thickness (CBT), T-CPD, I-CPD, and IOP, according to preoperative values, were found to be statistically significantly reduced. Preoperatively, in Group 2 patients, according to Group 1 patients, TIA and IOP were found to be statistically significantly increased. Preoperative and postoperative IOP between the measured parameters with UBM showed no statistically significant correlation. Conclusions. Gases cause more morphological changes in the anterior segment structures. It is thought that complications such as increased intraocular pressure can be seen more frequently for this reason.

  16. On the acoustic wedge design and simulation of anechoic chamber

    Science.gov (United States)

    Jiang, Changyong; Zhang, Shangyu; Huang, Lixi

    2016-10-01

    This study proposes an alternative to the classic wedge design for anechoic chambers, which is the uniform-then-gradient, flat-wall (UGFW) structure. The working mechanisms of the proposed structure and the traditional wedge are analyzed. It is found that their absorption patterns are different. The parameters of both structures are optimized for achieving minimum absorber depth, under the condition of absorbing 99% of normal incident sound energy. It is found that, the UGFW structure achieves a smaller total depth for the cut-off frequencies ranging from 100 Hz to 250 Hz. This paper also proposes a modification for the complex source image (CSI) model for the empirical simulation of anechoic chambers, originally proposed by Bonfiglio et al. [J. Acoust. Soc. Am. 134 (1), 285-291 (2013)]. The modified CSI model considers the non-locally reactive effect of absorbers at oblique incidence, and the improvement is verified by a full, finite-element simulation of a small chamber. With the modified CSI model, the performance of both decorations with the optimized parameters in a large chamber is simulated. The simulation results are analyzed and checked against the tolerance of 1.5 dB deviation from the inverse square law, stipulated in the ISO standard 3745(2003). In terms of the total decoration depth and anechoic chamber performance, the UGFW structure is better than the classic wedge design.

  17. Anterior migration of dexamethasone implant in a pseudophakic patient with intact posterior capsule

    Directory of Open Access Journals (Sweden)

    Nilufer Kocak

    2014-01-01

    Full Text Available Intravitreal application of Ozurdex ® (Allergan, Inc., Irvine, CA, USA which is a biodegradable, sustained-release dexamethasone implant has been reported to be effective in the treatment of macular edema. Migration of such implant into the anterior chamber has been recently described in cases without perfect zonular or the posterior capsular integrity. Herein, we report the first case with anterior migration of Ozurdex ® implant that mislocated just behind the intraocular lens (IOL in an intact capsular bag. It is thought that such implant migrated anteriorly towards into the posterior chamber through weak zonules as the present case had a medical history of uneventful phacoemulsification surgery with the implantation of posterior chamber IOL. However, the migrated implant was well tolerated since there was no sign of the corneal complication, rise in intraocular pressure, and anterior chamber reaction. Close follow-up was scheduled to find out any signs of anterior segment pathology. Meanwhile dexamethasone implant completely degraded at the 4 th month of postoperative follow-up.

  18. 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.

  19. 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.

  20. 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...

  1. Comparison of corneal topography and anterior chamber depth between patients wearing RGPCL and SCL%软性与透气性硬性角膜接触镜配戴者角膜地形图及前房深度对比分析

    Institute of Scientific and Technical Information of China (English)

    周路坦; 石迎辉

    2015-01-01

    目的 比较配戴软性及硬性角膜接触镜对角膜形态及前房深度的影响.方法 选取屈光不正患者60例(120眼),分别予以配戴软性角膜接触镜(soft contact lens,SCL)及透气性硬性角膜接触镜(rigid gas permeable contact lens,RGPCL),其中SCL组30例(60眼),RGPCL组30例(60眼),ObscanⅡ角膜地形图观察戴镜前及戴镜后1 a、2 a角膜屈光力、角膜前后表面Diff值、中央角膜厚度、前房深度的变化.结果 戴镜前RGPCL组角膜上下表面屈光力差值为(0.98±0.49)D,戴镜后1 a为(0.66±0.43)D,戴镜后2 a为(0.59±0.37)D,均较戴镜前减小(P<0.05);戴镜后1 a、2 a角膜前表面屈光力均较戴镜前降低,差异均有统计学意义(均为P<0.05).SCL组戴镜后1 a、2 a角膜前后表面屈光力、I-S值、前后表面Diff值、前房深度与戴镜前比较,差异均无统计学意义(均为P>0.05);戴镜前中央角膜厚度为(549±26)μm,戴镜后1 a为(527±29) μm,与戴镜前比较差异无统计学意义(P>0.05),戴镜后2 a为(509±31) μm,与戴镜前比较差异有统计学意义(P<0.05).结论 长期配戴RGPCL对角膜代谢和功能影响不明显,且能够提供更好的光学矫正效果.

  2. The ALICE time projection chamber

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    This time projection chamber is part of the ALICE detector on the new LHC accelerator at CERN. Particles produced in collisions at the core of the detector will follow paths outward through the various sub-detector layers. If these particles carry a charge, they will ionise the gas contained within this chamber producing an electric signal as the ions drift in the chamber's electric field.

  3. 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...

  4. 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

  5. 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

  6. LET measurements with a liquid ionization chamber

    Energy Technology Data Exchange (ETDEWEB)

    Tegami, Sara

    2013-02-08

    Deep-seated tumors can be efficiently treated with heavy charged particles. The characteristic depth dose profile inside the tissue (Bragg peak) allows to deliver a high dose inside the tumor, while sparing the neighboring healthy tissue. As compared to protons, heavy ions like carbon or oxygen produce a higher amount of ionization events along their track (and in particular at the end of the ion beam path), resulting in an irreparable damage to the DNA of the tumor cells. The density of such ionization events is described in terms of Linear Energy Transfer (LET), an important physical quantity, but difficult to be measured directly. The aim of this work is to determine LET of hadrontherapy beams by using Liquid Ionization Chambers (LIC). The ionization signal in LICs is affected by recombination effects that depend on the LET of the incident radiation. Differences in recombination effects in LICs and air-filled ionization chambers can be exploited to obtain the recombination index, which can be related to the LET, calculated by Monte Carlo methods. We thus developed a method to construct a calibration curve, which relates the recombination index with the LET at each depth in water. The result of this work can be used for online monitoring of the ion beam quality.

  7. Clinical application of TICL implantation for ametropia following deep anterior lamellar keratoplasty for keratoconus

    Science.gov (United States)

    Qin, Qin; Yang, Liping; He, Zifang; Huang, Zhenping

    2017-01-01

    Abstract Background: This study aimed to investigate the clinical application of phakic toric intraocular collamer lens (TICL) implantation in treating ametropia following deep anterior lamellar keratoplasty (DALK) for patients with keratoconus, especially the effectiveness and safety of high astigmatism and indications of TICL implantation after corneal transplantation. Methods: Using the self-controlled case series observation approach, 9 patients with ametropia (9 eyes) who underwent DALK surgery for keratoconus 1.5 years ago with stitches removed 3 months ago were kept under observation from May 2013 to April 2014 in Ophthalmic Center of Nanjing Drum Tower Hospital affiliated to Nanjing Medical University. TICL implantation was performed in all patients. The uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA) were examined before surgery and 1 week, 6 months, 1 year, and 2 years after surgery. Corneal astigmatism, corneal thickness, anterior chamber depth, corneal endothelial cell density (ECD), and preoperative and postoperative intraocular pressures at different time points were measured. Intraoperative or postoperative complications of TICL implantation were observed, and the safety of the operation was evaluated. Results: The UCVA and BCVA in all operated eyes were better 6 months after surgery than before surgery. The spherical diopter and cylindrical diopter decreased to different degrees after surgery. Six months after surgery, the deviation of TICL axis in all operated eyes was less than 10 degrees, tending to be stable. No severe intraoperative or postoperative complication occurred. Conclusion: TICL implantation was an optional choice for ametropia correction after DALK surgery, especially in patients with high astigmatism. PMID:28225492

  8. Development of Fission Chamber Assembly

    Institute of Scientific and Technical Information of China (English)

    YANGJinwei; ZHANGWei; SONGXianying; LIXu

    2003-01-01

    The fission chambers which are gas counters with fissile material inside chamber,provide essential information for plasma opcharacteristics. In conjunction with the neutron flux monitor system these provide time-resolved measurements of the global neutron source strength and fusion power from thermal nuclear fusion reactor as ITER for all plasma conditions for which neutrons are produced.

  9. The Big European Bubble Chamber

    CERN Multimedia

    1977-01-01

    The 3.70 metre Big European Bubble Chamber (BEBC), dismantled on 9 August 1984. During operation it was one of the biggest detectors in the world, producing direct visual recordings of particle tracks. 6.3 million photos of interactions were taken with the chamber in the course of its existence.

  10. [Anterior cervical hypertrichosis: case report].

    Science.gov (United States)

    Orozco-Gutiérrez, Mario H; Sánchez-Corona, José; García-Ortiz, José E; Castañeda-Cisneros, Gema; Dávalos-Rodríguez, Nory O; Corona-Rivera, Jorge R; García-Cruz, Diana

    2016-10-01

    The non-syndromic anterior cervical hypertrichosis (OMIM N° 600457) is a genetic disorder characterized by a patch of hair at the level of the laryngeal prominence. We present a 12-year-old boy with anterior cervical hypertrichosis and mild generalized hypertrichosis. He has no neurological, ophthalmological or skeletal anomalies. The clinical follow up is 10 years.

  11. National Ignition Facility Target Chamber

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-10-05

    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

  12. Ion chamber based neutron detectors

    Science.gov (United States)

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

    2014-12-16

    A neutron detector with monolithically integrated readout circuitry, including: a bonded semiconductor die; an ion chamber formed in the bonded semiconductor die; a first electrode and a second electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; and the readout circuitry which is electrically coupled to the first and second electrodes. The bonded semiconductor die includes an etched semiconductor substrate bonded to an active semiconductor substrate. The readout circuitry is formed in a portion of the active semiconductor substrate. The ion chamber has a substantially planar first surface on which the first electrode is formed and a substantially planar second surface, parallel to the first surface, on which the second electrode is formed. The distance between the first electrode and the second electrode may be equal to or less than the 50% attenuation length for neutrons in the neutron absorbing material filling the ion chamber.

  13. 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).

  14. Anterior uveitis following eyebrow epilation with alexandrite laser

    Directory of Open Access Journals (Sweden)

    Karabela Y

    2015-09-01

    Full Text Available Yunus Karabela,1 Mustafa Eliaçik2 1Department of Ophthalmology, Esenler Hospital, Istanbul Medipol University, Istanbul, Turkey; 2Department of Ophthalmology, Kadiköy Medipol Hospital, Istanbul Medipol University, Istanbul, Turkey Abstract: Ocular tissues are known to be sensitive to damage from exposure to laser emissions. This study reports the case of a female patient with acute unilateral anterior uveitis caused by alexandrite laser-assisted hair removal of the eyebrows. We report a 38-year-old female who presented with unilateral eye pain, redness, and photophobia after receiving alexandrite (755 nm laser epilation of both eyebrows. Best corrected visual acuity was 20/20 in both eyes. Right eye examination was normal. Left eye examination showed conjunctival injection and 2+/3+ cells in the anterior chamber. Intraocular pressure and fundus examination were normal. Topical steroids and cycloplegic drops were prescribed for 3 weeks. At the end of the 3-week follow-up, best corrected visual acuity was 20/20, and intraocular pressure and fundus examination were normal in both eyes. The left eye was white, and the anterior chamber was clear. The patient continues to be monitored. In conclusion, without adequate protective eyewear, laser hair removal of the eyebrows with alexandrite laser can lead to ocular damage. Keywords: uveitis, laser exposure, photothermolysis, laser hair removal, photoepilation

  15. Accuracy of corneal trephination depth using the Moria single-use adjustable depth vacuum trephine system

    Directory of Open Access Journals (Sweden)

    Fenzl CR

    2014-11-01

    Full Text Available Carlton R Fenzl,1 Adam J Gess,2 Majid Moshirfar31John A Moran Eye Center, University of Utah, Salt Lake City, UT, 2Eye Doctors of Washington, Washington, DC, 3Cornea and Refractive Surgery Division, Department of Ophthalmology, Francis I Proctor Foundation, University of California San Francisco, San Francisco, CA, USABackground: The Moria single-use adjustable depth trephine is a device that allows a goal trephination depth to be set prior to the surgical procedure.Methods: Eleven fresh human cadaveric eyes were trephined using 8.0 mm Moria single-use adjustable vacuum trephines. Prior to trephination, the average corneal pachymetry in the peripheral 7–10 mm range was obtained using anterior segment optical coherence tomography. The trephination depth was set to 80% of that value. Light microscopy was used to image anteroposterior cross-sections of each corneal specimen. Digital protractor software was used to evaluate the trephination angle, depth, and length. All adequately processed specimens were included in the analysis. In addition, trephination angle data from a previous publication by Moshirfar et al were used as a comparison with those of this study.Results: Trephination analysis of depth compared with pachymetry revealed a mean of 83.7%±6.53% (95% confidence interval 79.8–87.6. Maximum and minimum trephined depths were 95.35% and 71.3%, respectively. Trephination depth compared with angular corneal thickness yielded a mean of 66.2%±4.79% (95% confidence interval 63.0–69.4. Maximum and minimum depths were 73.7% and 59.7%, respectively. Analysis of trephination angle yielded a mean of 130.2±3.57 degrees (95% confidence interval 127.8–132.61. Maximum and minimum angles were 135.5 degrees and 126 degrees, respectively. The standard deviation of the trephination angle of the Moria trephine was found to be significantly less than that of Hessburg-Barron and Hanna trephines calculated in the previous study.Conclusion: The Moria

  16. Depth-Dependent Temporal Response Properties in Core Auditory Cortex

    OpenAIRE

    Christianson, G. Björn; Sahani, Maneesh; Linden, Jennifer F.

    2011-01-01

    The computational role of cortical layers within auditory cortex has proven difficult to establish. One hypothesis is that interlaminar cortical processing might be dedicated to analyzing temporal properties of sounds; if so, then there should be systematic depth-dependent changes in cortical sensitivity to the temporal context in which a stimulus occurs. We recorded neural responses simultaneously across cortical depth in primary auditory cortex and anterior auditory field of CBA/Ca mice, an...

  17. 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.

  18. Anterior segment study with the pentacam scheimpflug camera in refractive surgery candidates

    Directory of Open Access Journals (Sweden)

    Masih Hashemi

    2013-01-01

    Conclusions: Myopic eyes had steeper corneas than hyperopic eyes and anterior chamber measurements were significantly higher in the myopic eyes. In myopic eyes, AE max and PE max and K max measurements were higher, and ACD measurements were lower in the astigmatic groups.

  19. Oxygen depth profiling with subnanometre depth resolution

    Energy Technology Data Exchange (ETDEWEB)

    Kosmata, Marcel [Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, D-01314 Dresden (Germany); Munnik, Frans, E-mail: f.munnik@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, D-01314 Dresden (Germany); Hanf, Daniel; Grötzschel, Rainer [Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, D-01314 Dresden (Germany); Crocoll, Sonja [X-FAB Dresden GmbH and Co. KG, Grenzstraße 28, D-01109 Dresden (Germany); Möller, Wolfhard [Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, D-01314 Dresden (Germany)

    2014-10-15

    A High-depth Resolution Elastic Recoil Detection (HR-ERD) set-up using a magnetic spectrometer has been taken into operation at the Helmholtz-Zentrum Dresden-Rossendorf for the first time. This instrument allows the investigation of light elements in ultra-thin layers and their interfaces with a depth resolution of less than 1 nm near the surface. As the depth resolution is highly influenced by the experimental measurement parameters, sophisticated optimisation procedures have been implemented. Effects of surface roughness and sample damage caused by high fluences need to be quantified for each kind of material. Also corrections are essential for non-equilibrium charge state distributions that exist very close to the surface. Using the example of a high-k multilayer SiO{sub 2}/Si{sub 3}N{sub 4}O{sub x}/SiO{sub 2}/Si it is demonstrated that oxygen in ultra-thin films of a few nanometres thickness can be investigated by HR-ERD.

  20. Herds of methane chambers grazing bubbles

    Science.gov (United States)

    Grinham, Alistair; Dunbabin, Matthew

    2014-05-01

    Water to air methane emissions from freshwater reservoirs can be dominated by sediment bubbling (ebullitive) events. Previous work to quantify methane bubbling from a number of Australian sub-tropical reservoirs has shown that this can contribute as much as 95% of total emissions. These bubbling events are controlled by a variety of different factors including water depth, surface and internal waves, wind seiching, atmospheric pressure changes and water levels changes. Key to quantifying the magnitude of this emission pathway is estimating both the bubbling rate as well as the areal extent of bubbling. Both bubbling rate and areal extent are seldom constant and require persistent monitoring over extended time periods before true estimates can be generated. In this paper we present a novel system for persistent monitoring of both bubbling rate and areal extent using multiple robotic surface chambers and adaptive sampling (grazing) algorithms to automate the quantification process. Individual chambers are self-propelled and guided and communicate between each other without the need for supervised control. They can maintain station at a sampling site for a desired incubation period and continuously monitor, record and report fluxes during the incubation. To exploit the methane sensor detection capabilities, the chamber can be automatically lowered to decrease the head-space and increase concentration. The grazing algorithms assign a hierarchical order to chambers within a preselected zone. Chambers then converge on the individual recording the highest 15 minute bubbling rate. Individuals maintain a specified distance apart from each other during each sampling period before all individuals are then required to move to different locations based on a sampling algorithm (systematic or adaptive) exploiting prior measurements. This system has been field tested on a large-scale subtropical reservoir, Little Nerang Dam, and over monthly timescales. Using this technique

  1. Perforation forces of the intact porcine anterior lens capsule.

    Science.gov (United States)

    Ullrich, Franziska; Lussi, Jonas; Felekis, Dimitrios; Michels, Stephan; Petruska, Andrew J; Nelson, Bradley J

    2016-09-01

    During the first step of cataract surgery, the lens capsule is perforated and a circular hole is created with a sharp instrument, a procedure called capsulorhexis. To develop automated systems that can assist ophthalmologists during capsulorhexis, the forces required must be quantified. This study investigates perforation forces of the central anterior lens capsule in porcine eyes, which are used as a conservative model for the human eye. A micro-mechanical characterisation method is presented that measures capsular bag perforation forces with a high precision positioning and high-resolution force sensing system. The force during perforation of the anterior lens capsule was measured with various sized needles and indentation speeds and is found to be 15-35mN. A bio-mechanical model is identified that describes an exponential correlation between indentation force and depth, indicating strain hardening behaviour of the porcine anterior lens capsule.

  2. Complexity and Dynamical Depth

    Directory of Open Access Journals (Sweden)

    Terrence Deacon

    2014-07-01

    Full Text Available We argue that a critical difference distinguishing machines from organisms and computers from brains is not complexity in a structural sense, but a difference in dynamical organization that is not well accounted for by current complexity measures. We propose a measure of the complexity of a system that is largely orthogonal to computational, information theoretic, or thermodynamic conceptions of structural complexity. What we call a system’s dynamical depth is a separate dimension of system complexity that measures the degree to which it exhibits discrete levels of nonlinear dynamical organization in which successive levels are distinguished by local entropy reduction and constraint generation. A system with greater dynamical depth than another consists of a greater number of such nested dynamical levels. Thus, a mechanical or linear thermodynamic system has less dynamical depth than an inorganic self-organized system, which has less dynamical depth than a living system. Including an assessment of dynamical depth can provide a more precise and systematic account of the fundamental difference between inorganic systems (low dynamical depth and living systems (high dynamical depth, irrespective of the number of their parts and the causal relations between them.

  3. A case of anterior ischemic optic neuropathy associated with uveitis

    Directory of Open Access Journals (Sweden)

    Sugahara M

    2013-05-01

    Full Text Available Michitaka Sugahara, Takayuki Fujimoto, Kyoko Shidara, Kenji Inoue, Masato Wakakura Inouye Eye Hospital, Tokyo, Japan Introduction: Here, we describe a patient who presented with anterior ischemic optic neuropathy (AION and subsequently developed uveitis. Case: A 69-year-old man was referred to our hospital and initially presented with best-corrected visual acuities (BCVA of 20/40 (right eye and 20/1000 (left eye and relative afferent pupillary defect. Slit-lamp examination revealed no signs of ocular inflammation in either eye. Fundus examination revealed left-eye swelling and a pale superior optic disc, and Goldmann perimetry revealed left-eye inferior hemianopia. The patient was diagnosed with nonarteritic AION in the left eye. One week later, the patient returned to the hospital because of vision loss. The BCVA of the left eye was so poor that the patient could only count fingers. Slit-lamp examination revealed 1+ cells in the anterior chamber and the anterior vitreous in both eyes. Funduscopic examination revealed vasculitis and exudates in both eyes. The patient was diagnosed with bilateral panuveitis, and treatment with topical betamethasone was started. No other physical findings resulting from other autoimmune or infectious diseases were found. No additional treatments were administered, and optic disc edema in the left eye improved, and the retinal exudates disappeared in 3 months. The patient's BCVA improved after cataract surgery was performed. Conclusion: Panuveitis most likely manifests after the development of AION. Keywords: anterior ischemic optic neuropathy, uveitis

  4. Cyclically controlled welding purge chamber

    Science.gov (United States)

    Gallagher, Robert L. (Inventor)

    1996-01-01

    An arrangement for butt-welding cylindrical sections of large, thin-wall tanks includes a rotatable mandrel with side-by-side sets of radial position adjusters. Each set of adjusters bears on one of the tank sections adjacent the seam, to prevent the sections from sagging out-of-round. The mandrel rotates relative to the welder, so that a continuous seam is formed. A purge chamber is fixed in position behind the seam at the weld head, and is flushed with inert gas. The purge chamber includes a two-sided structure which is contiguous with the cylindrical sections and a circumferential vane to form an open-ended tube-like structure, through which the radial position adjusters pass as the mandrel and cylindrical workpiece sections rotate. The tube-like structure is formed into a chamber by a plurality of movable gates which are controlled to maintain a seal while allowing adjusters to progress through the purge chamber.

  5. 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.

  6. The PHENIX Time Expansion Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Rosati, M.; Barish, K.; Botelho, S.; Chang, W.C.; Gogoi, A.L. de; Dietzsch, O.; Ferdousi, T.; Franz, A.; Fung, S.Y.; Gannon, J.; Harder, J.; Kandasamy, A.; Khomutnikov, A.; Kotchekov, D.; Lebedev, A.; Li, X.H.; Mahon, J.; Munirassimann, M.; Negrin, J.; O' Brien, E.; O' Connor, P.; Pisani, R.; Rankowitz, S.; Seto, R.; Takagui, E.M.; Wang, H.Q

    1999-12-27

    The TEC/TRD subsystem will track all charged particles and contribute to the particle identification by the measurement of energy loss. The design, construction and testing of the TEC chambers are described.

  7. The PHENIX Time Expansion Chamber

    CERN Document Server

    Rosati, M; Botelho, S; Chang, W C; Gogoi, A L D; Dietzsch, O; Ferdousi, T; Franz, A; Fung, S Y; Gannon, J; Harder, J; Kandasamy, A; Khomutnikov, A; Kotchekov, D; Lebedev, A; Li, X H; Mahon, J; Munirassimann, M; Negrin, J; O'Brien, E; O'Connor, P; Pisani, R; Rankowitz, S; Seto, R; Takagui, E M; Wang, H Q

    1999-01-01

    The TEC/TRD subsystem will track all charged particles and contribute to the particle identification by the measurement of energy loss. The design, construction and testing of the TEC chambers are described.

  8. Vaporization chambers and associated methods

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Terry D.; Wilding, Bruce M.; McKellar, Michael G.; Shunn, Lee P.

    2017-02-21

    A vaporization chamber may include at least one conduit and a shell. The at least one conduit may have an inlet at a first end, an outlet at a second end and a flow path therebetween. The shell may surround a portion of each conduit and define a chamber surrounding the portion of each conduit. Additionally, a plurality of discrete apertures may be positioned at longitudinal intervals in a wall of each conduit, each discrete aperture of the plurality of discrete apertures sized and configured to direct a jet of fluid into each conduit from the chamber. A liquid may be vaporized by directing a first fluid comprising a liquid into the inlet at the first end of each conduit, directing jets of a second fluid into each conduit from the chamber through discrete apertures in a wall of each conduit and transferring heat from the second fluid to the first fluid.

  9. Vacuum chambers for LHC LSS

    CERN Document Server

    Costa-Pinto, P

    2004-01-01

    The approximately 6 km total length of the Large Hadron Collider (LHC) warm sections consist of about 1000 chambers. Most of these chambers, of various length and cross sections, are made of copper, but different lengths in stainless steel, mumetal, aluminium and beryllium will also be used. All the chambers will be internally coated with a thin film of TiZrV, to reduce both the secondary electron yield and the photon and electron stimulated desorption, with the further advantage of providing a huge additional pumping speed. In order to cope with the tight production schedule, a new dedicated coating facility was created, which allows four chambers to be coated per working day. This coating facility and its operating mode are described, together with the TiZrV film characteristics (structure, morphology) and performance (pumping speed, ultimate pressure, discharge gas outgassing).

  10. The Antiproton Depth-Dose Curve in Water

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael; Jäkel, Oliver

    2008-01-01

    We have measured the depth-dose curve of 126 MeV antiprotons in a water phantom using ionization chambers. Since the antiproton beam provided by CERN has a pulsed structure and possibly carries a high-LET component from the antiproton annihilation, it is necessary to correct the acquired charge...

  11. BEBC Big European Bubble Chamber

    CERN Multimedia

    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 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. On the wall perturbation correction for a parallel-plate NACP-02 chamber in clinical electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Zink, K.; Wulff, J. [University Hospital Marburg, Philipps-University, D-35043 Marburg, Germany and Institut fuer Medizinische Physik und Strahlenschutz - IMPS, University of Applied Sciences Giessen-Friedberg, D-35390 Giessen (Germany); Institut fuer Medizinische Physik und Strahlenschutz - IMPS, University of Applied Sciences Giessen-Friedberg, D-35390 Giessen (Germany)

    2011-02-15

    Purpose: In recent years, several Monte Carlo studies have been published concerning the perturbation corrections of a parallel-plate chamber in clinical electron beams. In these studies, a strong depth dependence of the relevant correction factors (p{sub wall} and p{sub cav}) for depth beyond the reference depth is recognized and it has been shown that the variation with depth is sensitive to the choice of the chamber's effective point of measurement. Recommendations concerning the positioning of parallel-plate ionization chambers in clinical electron beams are not the same for all current dosimetry protocols. The IAEA TRS-398 as well as the IPEM protocol and the German protocol DIN 6800-2 interpret the depth of measurement within the phantom as the water equivalent depth, i.e., the nonwater equivalence of the entrance window has to be accounted for by shifting the chamber by an amount {Delta}z. This positioning should ensure that the primary electrons traveling from the surface of the water phantom through the entrance window to the chamber's reference point sustain the same energy loss as the primary electrons in the undisturbed phantom. The objective of the present study is the determination of the shift {Delta}z for a NACP-02 chamber and the calculation of the resulting wall perturbation correction as a function of depth. Moreover, the contributions of the different chamber walls to the wall perturbation correction are identified. Methods: The dose and fluence within the NACP-02 chamber and a wall-less air cavity is calculated using the Monte Carlo code EGSnrc in a water phantom at different depths for different clinical electron beams. In order to determine the necessary shift to account for the nonwater equivalence of the entrance window, the chamber is shifted in steps {Delta}z around the depth of measurement. The optimal shift {Delta}z is determined from a comparison of the spectral fluence within the chamber and the bare cavity. The wall

  14. 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.

  15. Bluetooth Communication Interface for EEG Signal Recording in Hyperbaric Chambers.

    Science.gov (United States)

    Pastena, Lucio; Formaggio, Emanuela; Faralli, Fabio; Melucci, Massimo; Rossi, Marco; Gagliardi, Riccardo; Ricciardi, Lucio; Storti, Silvia F

    2015-07-01

    Recording biological signals inside a hyperbaric chamber poses technical challenges (the steel walls enclosing it greatly attenuate or completely block the signals as in a Faraday cage), practical (lengthy cables creating eddy currents), and safety (sparks hazard from power supply to the electronic apparatus inside the chamber) which can be overcome with new wireless technologies. In this technical report we present the design and implementation of a Bluetooth system for electroencephalographic (EEG) recording inside a hyperbaric chamber and describe the feasibility of EEG signal transmission outside the chamber. Differently from older systems, this technology allows the online recording of amplified signals, without interference from eddy currents. In an application of this technology, we measured EEG activity in professional divers under three experimental conditions in a hyperbaric chamber to determine how oxygen, assumed at a constant hyperbaric pressure of 2.8 ATA , affects the bioelectrical activity. The EEG spectral power estimated by fast Fourier transform and the cortical sources of the EEG rhythms estimated by low-resolution brain electromagnetic analysis were analyzed in three different EEG acquisitions: breathing air at sea level; breathing oxygen at a simulated depth of 18 msw, and breathing air at sea level after decompression.

  16. 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.

  17. Extreme skin depth waveguides

    CERN Document Server

    Jahani, Saman

    2014-01-01

    Recently, we introduced a paradigm shift in light confinement strategy and introduced a class of extreme skin depth (e-skid) photonic structures (S. Jahani and Z. Jacob, "Transparent sub-diffraction optics: nanoscale light confinement without metal," Optica 1, 96-100 (2014)). Here, we analytically establish that figures of merit related to light confinement in dielectric waveguides are fundamentally tied to the skin depth of waves in the cladding. We contrast the propagation characteristics of the fundamental mode of e-skid waveguides and conventional waveguides to show that the decay constant in the cladding is dramatically larger in e-skid waveguides, which is the origin of sub-diffraction confinement. Finally, we propose an approach to verify the reduced skin depth in experiment using the decrease in the Goos-H\\"anchen phase shift.

  18. 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.

  19. "Flat-Fish" Vacuum Chamber

    CERN Multimedia

    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.

  20. Impedances of Laminated Vacuum Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Burov, A.; Lebedev, V.; /Fermilab

    2011-06-22

    First publications on impedance of laminated vacuum chambers are related to early 70s: those are of S. C. Snowdon [1] and of A. G. Ruggiero [2]; fifteen years later, a revision paper of R. Gluckstern appeared [3]. All the publications were presented as Fermilab preprints, and there is no surprise in that: the Fermilab Booster has its laminated magnets open to the beam. Being in a reasonable mutual agreement, these publications were all devoted to the longitudinal impedance of round vacuum chambers. The transverse impedance and the flat geometry case were addressed in more recent paper of K. Y. Ng [4]. The latest calculations of A. Macridin et al. [5] revealed some disagreement with Ref. [4]; this fact stimulated us to get our own results on that matter. Longitudinal and transverse impendances are derived for round and flat laminated vacuum chambers. Results of this paper agree with Ref. [5].

  1. Evaluation of ion chamber dependent correction factors for ionisation chamber dosimetry in proton beams using a Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    Palmans, H. [Ghent Univ. (Belgium). Dept. of Biomedical Physics; Verhaegen, F.

    1995-12-01

    In the last decade, several clinical proton beam therapy facilities have been developed. To satisfy the demand for uniformity in clinical (routine) proton beam dosimetry two dosimetry protocols (ECHED and AAPM) have been published. Both protocols neglect the influence of ion chamber dependent parameters on dose determination in proton beams because of the scatter properties of these beams, although the problem has not been studied thoroughly yet. A comparison between water calorimetry and ionisation chamber dosimetry showed a discrepancy of 2.6% between the former method and ionometry following the ECHED protocol. Possibly, a small part of this difference can be attributed to chamber dependent correction factors. Indications for this possibility are found in ionometry measurements. To allow the simulation of complex geometries with different media necessary for the study of those corrections, an existing proton Monte Carlo code (PTRAN, Berger) has been modified. The original code, that applies Mollire`s multiple scattering theory and Vavilov`s energy straggling theory, calculates depth dose profiles, energy distributions and radial distributions for pencil beams in water. Comparisons with measurements and calculations reported in the literature are done to test the program`s accuracy. Preliminary results of the influence of chamber design and chamber materials on dose to water determination are presented.

  2. 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...

  3. Ionization Chamber Measures Extreme Ultraviolet

    Science.gov (United States)

    Carlson, Robert W.

    1987-01-01

    Ionization chamber operates in nearly total photon absorption as stable, self-calibrating detector of ionizing extreme ultraviolet radiation. Working gas of instrument is neon; photoionization properties well known and readily applicable to absolute measurements. Designed for measurements of solar ultraviolet flux aboard sounding rocket, instrument used on Earth to measure ultraviolet radiation in vacuum systems. Ionization chamber collects positive neon ions and electrons produced by irradiation of neon gas by ultraviolet photons. Approximately one ion produced by each photon; consequently, photoionization current nearly proportional to photon flux.

  4. The Clinical Analysis of Secondary Glaucoma Following Posterior Chamber Intraocular Lens Implantation

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    We present 14 patients with secondary gluacoma following the implantation of a posterior chamber intraocular lens (lOLs). All patients were u-nilateral gluacoma , which developed within 1 month following the IOL implantation in 10 cases, and from 1 to 3 years in 4 cases. The angle of anterior chamber was open in 8 patients, and close in 6 ones. Seven patients required treatment of antiglaucomatous medicine; 4 patients underwent laser indecto-my and 3 patients required antiglaucoma surgery. The results s...

  5. 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.

  6. A dual deformable reverberation chamber

    NARCIS (Netherlands)

    Leferink, Frank

    2010-01-01

    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

  7. Bubble chamber: colour enhanced tracks

    CERN Multimedia

    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.

  8. 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.

  9. Posterior chamber phakic intraocular lens implantation for high myopia

    Institute of Scientific and Technical Information of China (English)

    沈晔; 杜持新; 顾扬顺; 王竞

    2003-01-01

    Objective To evaluate the efficacy, safety and stability of posterior chamber phakic intraocular lens (PIOLs) implantation for the correction of high myopia.Methods Thirty-nine eyes of twenty patients with high myopia (between-11.75 and-25.75 diopters) had a posterior chamber PIOL (Staar ICL) implanted. During 6-48 months' follow-up, visual acuity, refraction, intraocular pressure (IOP), corneal reaction and space between crystal lens and intraocular lens (IOLs) were tested.Results Successful implantation was achieved in all patients. Visual acuity without correction greater than 0.5 was found in 34 eyes at 1 day and 3 months postoperatively. Thirty-five eyes maintained a low negative power of refraction (-1.42±1.32 doipters), which did not prevent the patients from most of their daily activities. During 3-48 months' follow-up, refraction was stable and no cornea edema and glaucoma was found. Two eyes of one patient had corticosteroid glaucoma and another eye showed cataractogenesis under anterior capsular membrane.Conclusion Posterior chamber PIOL implantation is predictable, safe, and effective in the correction of high myopia, and its indications should be carefully selected.

  10. 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.

  11. 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

  12. Anterior cruciate ligament - updating article.

    Science.gov (United States)

    Luzo, Marcus Vinicius Malheiros; Franciozi, Carlos Eduardo da Silveira; Rezende, Fernando Cury; Gracitelli, Guilherme Conforto; Debieux, Pedro; Cohen, Moisés

    2016-01-01

    This updating article on the anterior cruciate ligament (ACL) has the aim of addressing some of the most interesting current topics in this field. Within this stratified approach, it contains the following sections: ACL remnant; anterolateral ligament and combined intra and extra-articular reconstruction; fixation devices; and ACL femoral tunnel creation techniques.

  13. Anterior cruciate ligament - updating article

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Malheiros Luzo

    2016-08-01

    Full Text Available ABSTRACT This updating article on the anterior cruciate ligament (ACL has the aim of addressing some of the most interesting current topics in this field. Within this stratified approach, it contains the following sections: ACL remnant; anterolateral ligament and combined intra and extra-articular reconstruction; fixation devices; and ACL femoral tunnel creation techniques.

  14. Assessment of Anterior Segment Changes in Pseudophakic Eyes, Using Ultrasonic Biomicroscopic Imaging, after Pars Plana Vitrectomy with Silicone Oil or Gas Tamponade

    Directory of Open Access Journals (Sweden)

    Erkan Ünsal

    2016-01-01

    Full Text Available Objective. To evaluate the morphological changes of the anterior segment using ultrasonic biomicroscopy (UBM imaging in pseudophakic patients who underwent pars plana vitrectomy (PPV with silicone oil or gas (C3F8 internal tamponade agent injection. Method. This prospective study included pseudophakic patients with planned PPV, divided into two groups according to internal tamponade agent: those in which silicone oil was used (n=27, Group 1 and those in which gas (C3F8 was used (n=24, Group 2. UBM measurements were performed in the supine position before and one week after surgery. Results. In patients of Group 1, postoperative trabecular meshwork-ciliary process distance (T-CPD and iris-ciliary process distance (I-CPD, according to preoperative values, were found to be statistically significantly reduced, and postoperative mean value of scleral thickness (ST and intraocular pressure (IOP, according to preoperative value, was found to be statistically significantly increased. In patients of Group 2, postoperative mean values of anterior chamber depth (ACD, ciliary body thickness (CBT, T-CPD, I-CPD, and IOP, according to preoperative values, were found to be statistically significantly reduced. Preoperatively, in Group 2 patients, according to Group 1 patients, TIA and IOP were found to be statistically significantly increased. Preoperative and postoperative IOP between the measured parameters with UBM showed no statistically significant correlation. Conclusions. Gases cause more morphological changes in the anterior segment structures. It is thought that complications such as increased intraocular pressure can be seen more frequently for this reason.

  15. MANIFEST OF DEPTH SOCIOPSYCHOLOGY

    OpenAIRE

    ZELITCHENKO ALEXANDER

    2013-01-01

    The observations of motives of activity of big groups (nations, confessions etc.) as a whole result in discovery of the part of unconscious mind that is common for all members of big group a collective unconscious. Two parts of collective unconscious may be determined: the collective superconscious known first as a group archetype and the collective subconscious, which manifest itself for example in phenomenon of collective trauma. Depth sociopsychology is a science about the collective uncon...

  16. Fluoroscopically-Guided Posterior Approach for Shoulder Magnetic Resonance Arthrography: Comparison with Conventional Anterior Approach

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Koun J.; Ha, Doo Hoe; Lee, Sang Min [Dept. of Radiology, CHA Budang Medical Center, CHA University College of Medicine, Seongnam (Korea, Republic of)

    2011-10-15

    To prospectively evaluate the usefulness of the fluoroscopically-guided posterior approach compared with the anterior approach for shoulder magnetic resonance(MR) arthrography. Institutional review board approval and informed consent were obtained. Among 60 shoulder MR arthrographies performed on 59 patients with symptomatic shoulders, an intra-articular injection was performed (30 cases using the anterior approach and 30 using the posterior approach). Procedure-related pain was assessed by using a 5 score visual analogue scale (VAS). Depth of the puncture and standardized depth of puncture by body mass index (BMI) were recorded. The contrast leakage along the course of the puncture was evaluated by reviewing the MR. The statistical analyses included the Mann-Whitney U and Kruskal-Wallis test. There was no significant difference in VAS scores between the anterior and posterior groups (1.77 {+-} 1.10 vs. 1.80 {+-} 0.96). Depth of puncture and standardized depth of puncture by BMI were significantly shorter in the posterior group than those in the anterior group (4.4 {+-} 0.8 cm and 1.8 {+-} 0.3 cm vs. 6.6 {+-} 0.9 cm and 2.8 {+-} 0.4 cm, p < 0.001), respectively. The incidence of contrast leakage was more frequent in the posterior group (p = 0.003). The posterior approach will be useful in shoulder MR arthrography with a suspected anterior pathology, a postoperative follow-up study or obese patient.

  17. Closed chamber globe stabilization and needle capsulorhexis using irrigation hand piece of bimanual irrigation and aspiration system

    Directory of Open Access Journals (Sweden)

    Rai Harminder K

    2005-08-01

    Full Text Available Abstract Background The prerequisites for a good capsulorhexis include a deep, well maintained anterior chamber, globe stabilization and globe manipulation. This helps to achieve a capsulorhexis of optimal size, shape and obtain the best possible position for a red glow under retroillumination. We report the use of irrigation handpiece of bimanual irrigation aspiration system to stabilize the globe, maintain a deep anterior chamber and manipulate the globe to a position of optimal red reflex during needle capsulorhexis in phacoemulsification. Methods Two side ports are made with 20 G MVR 'V' lance knife (Alcon, USA. The irrigation handpiece with irrigation on is introduced into the anterior chamber through one side port and the 26-G cystitome (made from 26-G needle is introduced through the other. The capsolurhexis is completed with the needle. Results Needle capsulorhexis with this technique was used in 30 cases of uncomplicated immature senile cataracts. 10 cases were done under peribulbar anaesthesia and 20 under topical anaesthesia. A complete capsulorhexis was achieved in all cases. Conclusion The irrigating handpiece maintains deep anterior chamber, stabilizes the globe, facilitates pupillary dilatation, and helps in maintaining the eye in the position with optimal red reflex during needle capsulorhexis. This technique is a safe and effective way to perform needle capsulorhexis.

  18. Válvula de uretra anterior Anterior urethral valves

    Directory of Open Access Journals (Sweden)

    Silvio Tucci Jr.

    2003-02-01

    Full Text Available Objetivo: apresentar os aspectos clínicos, diagnósticos e terapêuticos de pacientes portadores de válvula da uretra anterior. Descrição: em dois neonatos, o diagnóstico presuntivo de patologia obstrutiva do trato urinário foi sugerido pela ultra-sonografia realizada no período pré-natal, confirmando-se o diagnóstico de válvula de uretra anterior pela avaliação pós-natal. Os pacientes foram submetidos a tratamento cirúrgico paliativo, com vesicostomia temporária e, posteriormente, definitivo, pela fulguração endoscópica das válvulas. Ambos evoluíram com função renal normal. Comentários: a válvula da uretra anterior é anomalia rara que deve ser considerada em meninos com quadro radiológico pré-natal sugestivo de obstrução infravesical, secundariamente à hipótese mais comum de válvula da uretra posterior. Ressaltamos a utilização da vesicostomia como derivação urinária temporária nestes casos, prevenindo potenciais complicações pela manipulação da uretra do recém-nascido.Objective: to discuss clinical signs, diagnostic tools and therapeutics of anterior urethral valves, an obstructive anomaly of the urinary system in males. Description: signs of urinary tract obstruction were identified on pre-natal ultrasound in two male fetuses and the diagnosis of anterior urethral valves was made through post-natal evaluation. As an initial treatment, vesicostomy was performed in both patients. Later, the valves were fulgurated using an endoscopic procedure. During the follow-up period both patients presented normal renal function. Comments: anterior urethral valves are a rare form of urethral anomaly that must be ruled out in boys with pre-natal ultrasound indicating infravesical obstruction. Vesicostomy used as an initial treatment rather than transurethral fulguration may prevent potential complications that can occur due to the small size of the neonatal urethra.

  19. Growing and Analyzing Biofilms in Flow Chambers

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim; Sternberg, Claus

    2011-01-01

    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...... 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...

  20. Growing and analyzing biofilms in flow chambers

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim; Sternberg, Claus

    2011-01-01

    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...... 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...

  1. Location and Pressures Change Prediction of Bromo Volcano Magma Chamber Using Inversion Scheme

    Science.gov (United States)

    Kumalasari, Ratih; Srigutomo, Wahyu

    2016-08-01

    Bromo volcano is one of active volcanoes in Indonesia. It has erupted at least 50 times since 1775 and has been monitored by Global Positioning System (GPS) since 1989. We applied the Levenberg-Marquardt inversion scheme to estimate the physical parameters contributing to the surface deformation. Physical parameters obtained by the inversion scheme such as magma chamber location and volume change are useful in monitoring and predicting the activity of Bromo volcano. From our calculation it is revealed that the depth of the magma chamber d = 6307.6 m, radius of magma chamber α = 1098.6 m and pressure change ΔP ≈ 1.0 MPa.

  2. Anterior lamina cribrosa surface position in idiopathic intracranial hypertension and glaucoma

    DEFF Research Database (Denmark)

    Villarruel, Jenni Martinez; Li, Xiao; Bach-Holm, Daniella;

    2017-01-01

    PURPOSE: To compare the anterior lamina cribrosa (LC) surface position in patients with idiopathic intracranial hypertension (IIH), primary open-angle glaucoma (high-tension glaucoma [HTG] and normal-tension glaucoma [NTG]), and healthy controls using enhanced depth imaging spectral-domain optical...... the Bruch membrane opening plane to the anterior LC surface, was manually measured on selected B-scans covering the central three-quarters of the optic nerve head in each eye. RESULTS: Mean LC depth in patients with IIH (325.2 ± 92.1 µm) was significantly (p<0.01) decreased compared to control subjects...

  3. A portable miniature anechoic chamber

    Science.gov (United States)

    Lorthioir, Jack; Gavin, Paul

    The portable miniature anechoic chamber (PMAC), a low-cost alternative to a full-size anechoic chamber, is presented. The PMAC is a miniature, enclosed, RF-tight microwave antenna range, which approximates the performance of an indoor range over the C through Ku (G through J)-band frequencies. The small footprint, four by six feet, allows for ease of movement by one person to a test site, indoors or outdoors. The PMAC can be used at I (intermediate)-level to support the operational readiness (OR) requirements of the U.S. Army, Navy or Air Force. In conjunction with the antenna test equipment (ATE), and under TPS control, it can be used for performance verification, fault detection and fault isolation. A typical application using the PMAC in this operating mode is described.

  4. LEP vacuum chamber, early prototype

    CERN Multimedia

    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).

  5. Development of multiwire proportional chambers

    CERN Multimedia

    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.

  6. Actuator System with Dual Chambers

    DEFF Research Database (Denmark)

    2015-01-01

    (8), the lid having a shaft opening (17) for a shaft (6) coupled to the magnetic rotor (5), wherein the magnetic rotor (5), when inserted in the translator cylinder (2), is arranged to translate a linear movement of the translator cylinder (2) into a rotational movement of the magnetic rotor by using...... magnetic flux (82) interacting between the magnetic stator and the magnetic rotor, said rotational movements is being transferred through a shaft (6), the lid (8) with a shaft opening (17) arranged for receiving the shaft (6), wherein the shaft is arranged to make both the linear and the rotational...... movement in the shaft opening (17), the lid (8) being arranged for confining the second end (15) of the translator cylinder (2), the translator cylinder confined by the lid (8) forms,when divided by the magnetic rotor (5), a first chamber (TC) with a first volume and a second chamber(BC) with a second...

  7. NRAO RF Anechoic Chamber & Antenna 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...

  8. MPS II drift chamber system

    Energy Technology Data Exchange (ETDEWEB)

    Platner, E.D.

    1982-01-01

    The MPS II detectors are narrow drift space chambers designed for high position resolution in a magnetic field and in a very high particle flux environment. Central to this implementation was the development of 3 multi-channel custom IC's and one multi-channel hybrid. The system is deadtimeless and requires no corrections on an anode-to-anode basis. Operational experience and relevance to ISABELLE detectors is discussed.

  9. Asymptomatic fistula from a giant aneurysmatic left anterior descending artery to the right ventricular outflow tract.

    Science.gov (United States)

    Mustelier, Juan Valiente; Rego, Julio Oscar Cabrera; Aquiles, Eddy W Olivares; Llerena, Luis Roberto

    2010-12-01

    Coronary artery fistulas are unusual congenital or acquired coronary artery abnormalities in which blood is shunted into a cardiac chamber, great vessel or other structure, bypassing the myocardial capillary network (Jung et al. in Cardiovasc Ultrasound 5:10, 2007). We present a young adult patient with an asymptomatic fistula from a giant aneurysmatic left anterior descending artery to the right ventricular outflow tract, first diagnosed by echocardiography examination and further confirmed by 128-slice computed tomography coronary angiography.

  10. Coronary Artery and Pulmonary Artery Fistula Originated from Significant Stenosis in the Left Anterior Descending Artery

    Directory of Open Access Journals (Sweden)

    Alper Sami Kunt

    2013-01-01

    Full Text Available Coronary artery fistula (CAF is defined as a rare anomalous connection between a coronary artery and a major vessel or a cardiac chamber. We report a case of a left anterior descending coronary (LAD stenosis and coronary artery fistula between the LAD coronary artery and the pulmonary artery (PA. CAF is often diagnosed by coronary angiogram. We describe our diagnostic approach and review the literature on the epidemiology, the pathophysiology, the diagnostic modalities, and the treatment options.

  11. Fenestration of the anterior cerebral artery

    Energy Technology Data Exchange (ETDEWEB)

    Ito, J.; Washiyama, K.; Hong, K.C.; Ibuchi, Y.

    1981-08-01

    Three cases of angiographically demonstrated fenestration of the anterior cerebral artery are reported. Fenestration occurred at the medial half of the horizontal segment of the anterior cerebral artery in all cases. Its embryology and clinical significance are briefly discussed, and the anatomical and radiological literature on fenestration of the anterior cerebral artery is reviewed.

  12. 38 CFR 3.379 - Anterior poliomyelitis.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Anterior poliomyelitis. 3... Specific Diseases § 3.379 Anterior poliomyelitis. If the first manifestations of acute anterior poliomyelitis present themselves in a veteran within 35 days of termination of active military service, it...

  13. Epidermoid cyst in Anterior, Middle

    Directory of Open Access Journals (Sweden)

    Kankane Vivek Kumar

    2016-09-01

    Full Text Available Epidermoid cysts are benign slow growing more often extra-axial tumors that insinuate between brain structures, we present the clinical, imaging, and pathological findings in 35 years old female patients with atypical epidermoid cysts which was situated anterior, middle & posterior cranial fossa. NCCT head revealed hypodense lesion over right temporal and perisylvian region with extension in prepontine cistern with mass effect & midline shift and MRI findings revealed a non-enhancing heterogeneous signal intensity cystic lesion in right frontal & temporal region extending into prepontine cistern with restricted diffusion. Patient was detoriated in night of same day of admission, emergency Fronto-temporal craniotomy with anterior peterousectomy and subtotal resection was done. The histological examination confirms the epidermoid cyst. The timing of ectodermal tissue sequestration during fetal development may account for the occurrence of atypical epidermoid cysts.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Surgical Management of Significant Maxillary Anterior Vertical Ridge Defects.

    Science.gov (United States)

    Urban, Istvan A; Monje, Alberto; Nevins, Myron; Nevins, Marc L; Lozada, Jamie L; Wang, Hom-Lay

    2016-01-01

    Severe vertical ridge deficiency in the anterior maxilla represents one of the most challenging scenarios in bone regeneration. Under ideal circumstances, guided bone regeneration in combination with soft tissue management has shown predictable esthetic and functional outcomes. Success largely relies on primary wound closure during and after the surgical procedure. Surgical sites present different challenges that need to be considered when designing the flap. The goal of this article is to propose a classification of flap designs that considers vestibular depth and scar formation around the periosteum when performing vertical ridge augmentation in the atrophic anterior maxilla. The four clinical conditions proposed under this classification are (1) shallow vestibule with healthy periosteum, (2) deep vestibule with healthy periosteum, (3) shallow vestibule with scarred periosteum, and (4) deep vestibule with scarred periosteum. The classification will allow clinicians to achieve tension-free closure and more predictable vertical bone gain.

  16. Wire chamber degradation at the Argonne ZGS

    Energy Technology Data Exchange (ETDEWEB)

    Haberichter, W.; Spinka, H.

    1986-01-01

    Experience with multiwire proportional chambers at high rates at the Argonne Zero Gradient Synchrotron is described. A buildup of silicon on the sense wires was observed where the beam passed through the chamber. Analysis of the chamber gas indicated that the density of silicon was probably less than 10 ppM.

  17. 21 CFR 868.5470 - Hyperbaric chamber.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hyperbaric chamber. 868.5470 Section 868.5470 Food... DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5470 Hyperbaric chamber. (a) Identification. A hyperbaric chamber is a device that is intended to increase the environmental oxygen pressure to promote...

  18. 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.

  19. Coincidence of Varicella-Zoster Virus Anterior Uveitis in a Patient with Chandler's Syndrome

    Directory of Open Access Journals (Sweden)

    Takeshi Joko

    2013-11-01

    Full Text Available Purpose: We report a patient who, based on the clinical manifestations, was originally diagnosed as having Chandler's syndrome and later developed varicella-zoster virus (VZV DNA-positive anterior uveitis. Methods: The patient with Chandler's syndrome who manifested anterior uveitis underwent a complete ophthalmologic examination. Polymerase chain reaction (PCR was used to amplify the viral DNA in the aqueous humor to determine the cause of the intraocular inflammation. Results: Slit-lamp biomicroscopy showed focal iris atrophy and peripheral anterior synechiae (PAS; specular microscopy of the corneal endothelium disclosed the hammered-silver appearance. Based on these clinical findings, we diagnosed this patient as having Chandler's syndrome. During the follow-up period, however, the inflammatory cells suddenly appeared in the anterior chamber with formation of keratic precipitates and an increased intraocular pressure (IOP. VZV DNA was displayed in the aqueous humor by PCR. Based upon the diagnosis of VZV anterior uveitis, corticosteroids and acyclovir were given topically and systemically. The inflammation subsided with these medications; however, trabeculectomy was finally needed to control the IOP due to PAS progression. Conclusion: The coincidence of VZV anterior uveitis with Chandler's syndrome may constitute an implication for the possible viral etiology of iridocorneal endothelial syndrome.

  20. Selective importance of the rat anterior thalamic nuclei for configural learning involving distal spatial cues.

    Science.gov (United States)

    Dumont, Julie R; Amin, Eman; Aggleton, John P

    2014-01-01

    To test potential parallels between hippocampal and anterior thalamic function, rats with anterior thalamic lesions were trained on a series of biconditional learning tasks. The anterior thalamic lesions did not disrupt learning two biconditional associations in operant chambers where a specific auditory stimulus (tone or click) had a differential outcome depending on whether it was paired with a particular visual context (spot or checkered wall-paper) or a particular thermal context (warm or cool). Likewise, rats with anterior thalamic lesions successfully learnt a biconditional task when they were reinforced for digging in one of two distinct cups (containing either beads or shredded paper), depending on the particular appearance of the local context on which the cup was placed (one of two textured floors). In contrast, the same rats were severely impaired at learning the biconditional rule to select a specific cup when in a particular location within the test room. Place learning was then tested with a series of go/no-go discriminations. Rats with anterior thalamic nuclei lesions could learn to discriminate between two locations when they were approached from a constant direction. They could not, however, use this acquired location information to solve a subsequent spatial biconditional task where those same places dictated the correct choice of digging cup. Anterior thalamic lesions produced a selective, but severe, biconditional learning deficit when the task incorporated distal spatial cues. This deficit mirrors that seen in rats with hippocampal lesions, so extending potential interdependencies between the two sites.

  1. Time Evolution of Thermo-Mechanically and Chemically Coupled Magma Chambers

    Science.gov (United States)

    Ozimek, C.; Karlstrom, L.; Erickson, B. A.

    2015-12-01

    Complexity in the volcanic eruption cycle reflects time variation both of magma inputs to the crustal plumbing system and of crustal melt storage zones (magma chambers). These data include timing and volumes of eruptions, as well as erupted compositions. Thus models must take into account the coupled nature of physical attributes. Here we combine a thermo-mechanical model for magma chamber growth and pressurization with a chemical model for evolving chamber compositions, in the limit of rapid mixing, to study controls on eruption cycles and compositions through time. We solve for the mechanical evolution of a 1D magma chamber containing melt, crystals and bubbles, in a thermally evolving and viscoelastic crust. This pressure and temperature evolution constrains the input values of a chemical box model (Lee et al., 2013) that accounts for recharge, eruption, assimilation and fractional crystallization (REAFC) within the chamber. We plan to study the influence of melt supply, input composition, and chamber depth eruptive fluxes and compositions. Ultimately we will explore multiple chambers coupled by elastic-walled dikes. We expect that this framework will facilitate self-consistent inversion of long-term eruptive histories in terms of magma transport physics. Lee, C.-T. A., Lee, T.-C., Wu, C.-T., 2013. Modeling the compositional evolution of recharging, evacuating, and fractionating (REFC) magma chambers: Implications for differentiationof arc magmas. Geochemica Cosmochimica Acta, http://dx.doi.org/10.1016/j.gca.2013.08.009.

  2. Isotopic evidence for multiple contributions to felsic magma chambers

    DEFF Research Database (Denmark)

    Waight, Tod Earle; Wiebe, R.A.; Krogstad, E.J.

    2007-01-01

    by contemporaneous mafic magmas; the transition between the two now preserved as a zone of chilled mafic sheets and pillows in granite. Mafic components have highly variably isotopic compositions as a result of contamination either at depth or following injection into the magma chamber. Intermediate dikes...... with identical isotopic compositions to more mafic dikes suggest that closed system fractionation may be occurring in deeper level chambers prior to injection to shallower levels. The granitic portion of the pluton has the highest Nd isotopic composition (eNd=+3.0) of plutons in the region whereas the mafic...... lithologies have Nd isotopic compositions (eNd=+3.5) that are the lowest in the region and similar to the granite and suggestive of prolonged interactions and homogenization of the two components. Sr and Nd isotopic data for felsic enclaves are inconsistent with previously suggested models of diffusional...

  3. MR determination of neonatal spinal canal depth

    Energy Technology Data Exchange (ETDEWEB)

    Arthurs, Owen, E-mail: owenarthurs@uk2.net [Centre for Cardiovascular MR, Great Ormond Street Hospital for Children, London WC1N 3JH (United Kingdom); Thayyil, Sudhin, E-mail: s.thayyil@ucl.ac.uk [Academic Neonatology, Institute for Women' s Health, London WC1E 6AU (United Kingdom); Wade, Angie, E-mail: a.wade@ucl.ac.uk [Centre for Paediatric Epidemiology and Biostatistics, UCL Institute of Child Health, London (United Kingdom); Chong, W.K., E-mail: Kling.Chong@gosh.nhs.uk [Paediatric Neuroradiology, Great Ormond Street Hospital for Children, London (United Kingdom); Sebire, Neil J., E-mail: Neil.Sebire@gosh.nhs.uk [Histopathology, Great Ormond Street Hospital for Children, London WC1E 6AU (United Kingdom); Taylor, Andrew M., E-mail: a.taylor76@ucl.ac.uk [Centre for Cardiovascular MR, Cardiorespiratory Unit, Great Ormond Street Hospital for Children and UCL Institute of Cardiovascular Science, London WC1E 6AU (United Kingdom)

    2012-08-15

    Objectives: Lumbar punctures (LPs) are frequently performed in neonates and often result in traumatic haemorrhagic taps. Knowledge of the distance from the skin to the middle of the spinal canal (mid-spinal canal depth - MSCD) may reduce the incidence of traumatic taps, but there is little data in extremely premature or low birth weight neonates. Here, we determined the spinal canal depth at post-mortem in perinatal deaths using magnetic resonance imaging (MRI). Patients and methods: Spinal canal depth was measured in 78 post-mortem foetuses and perinatal cases (mean gestation 26 weeks; mean weight 1.04 kg) at the L3/L4 inter-vertebral space at post-mortem MRI. Both anterior (ASCD) and posterior (PSCD) spinal canal depth were measured; MSCD was calculated and modelled against weight and gestational age. Results: ASCD and PSCD (mm) correlated significantly with weight and gestational age (all r > 0.8). A simple linear model MSCD (mm) = 3 Multiplication-Sign Weight (kg) + 5 was the best fit, identifying an SCD value within the correct range for 87.2% (68/78) (95% CI (78.0, 92.9%)) cases. Gestational age did not add significantly to the predictive value of the model. Conclusion: There is a significant correlation between MSCD and body weight at post-mortem MRI in foetuses and perinatal deaths. If this association holds in preterm neonates, use of the formula MSCD (mm) = 3 Multiplication-Sign Weight (kg) + 5 could result in fewer traumatic LPs in this population.

  4. Comment on ‘Proton beam monitor chamber calibration’

    Science.gov (United States)

    Palmans, Hugo; Vatnitsky, Stanislav M.

    2016-09-01

    We comment on a recent article (Gomà et al 2014 Phys. Med. Biol. 59 4961-71) which compares different routes of reference dosimetry for the energy dependent beam monitor calibration in scanned proton beams. In this article, a 3% discrepancy is reported between a Faraday cup and a plane-parallel ionization chamber in the experimental determination of the number of protons per monitor unit. It is further claimed that similar discrepancies between calorimetry and ionization chamber based dosimetry indicate that {{k}Q} -values tabulated for proton beams in IAEA TRS-398 might be overestimated. In this commentary we show, however, that this supporting argument misrepresents the evidence in the literature and that the results presented, together with published data, rather confirm that there exist unresolved problems with Faraday cup dosimetry. We also show that the comparison in terms of the number of protons gives a biased view on the uncertainty estimates for both detectors while the quantity of interest is absorbed dose to water or dose-area-product to water, even if a beam monitor is calibrated in terms of the number of protons. Gomà et al (2014 Phys. Med. Biol. 59 4961-71) also report on the discrepancy between cylindrical and plane-parallel ionization chambers and confirm experimentally that in the presence of a depth dose gradient, theoretical values of the effective point of measurement, or alternatively a gradient correction factor, account for the discrepancy. We believe this does not point to an error or shortcoming of IAEA TRS-398, which prescribes taking the centre of cylindrical ionization chambers as reference point, since it recommends reference dosimetry to be performed in the absence of a depth dose gradient. But these observations reveal that important aspects of beam monitor calibration in scanned proton beams are not addressed in IAEA TRS-398 given that those types of beams were not widely implemented at the time of its publication.

  5. Application of ultrasound biomicro-scopy in the planning of cataract surgery in anterior megalophthalmos

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Zare

    2011-01-01

    Full Text Available Anterior megalophthalmos, a rare hereditary disorder, is macrocornea (horizontal corneal diameter more than 13 mm in association with enlarged lens-iris diaphragm and ciliary ring. One of the major challenging issues in the cataract surgery of these patients is preventing intraocular lens (IOL malposition, because of probable large capsular bag. Several approaches have been selected by previous surgeons, such as, custom-made anterior chamber IOLs. In this study, we show a normal capsular bag diameter despite ciliary ring enlargement, with application of ultrasound biomicroscopy (UMB. We suggest that in cases of anterior megalophthalmos without phacodonesis, UBM could measure the actual size of the capsular bag and obviate the need for further procedures.

  6. Spontaneous fracture of an implanted posterior chamber polyimide intraocular lens haptic: A case report

    Directory of Open Access Journals (Sweden)

    Haemin Kang

    2014-01-01

    Full Text Available A 57-year-old male patient visited our clinic for decreased visual acuity in the right eye for 10 days. He denied any trauma history, but recalled that the symptom developed after straining. He had undergone uncomplicated phacoemulsification and posterior chamber intraocular lens (IOL implantation in the bag of the right eye 11 years ago. The IOL was a three-piece silicone polyimide-haptics design. On slit-lamp examination, the IOL optic and proximal part of nasal fractured haptic were found in the anterior chamber. The distal part of fractured haptic was observed in the capsular bag. He underwent IOL exchange. The fracture site of the haptic was near the optic-haptic junction. This is the unique case report of a spontaneous fracture of an implanted posterior chamber polyimide IOL haptic, which implies the possibility of IOL haptic fracture in various haptic materials.

  7. 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...

  8. Loss of ions in cavity ionization chambers

    Energy Technology Data Exchange (ETDEWEB)

    Takata, N. [Ionizing Radiation Section, NMIJ/AIST, Tsukuba 305-8568 (Japan)]. E-mail: n.takata@aist.go.jp; Tran, N.T. [Institute for Nuclear Science and Technique, VAEC, Hanoi (Viet Nam); Kim, E. [Radiation Safety Section, NIRS, Inageku, Chiba-city 263-8555 (Japan); Marsoem, P. [P3KRBiN-BATAN, JL Cinere-Pasar Jum' at, Jakarta 12070 (Indonesia); Kurosawa, T. [Ionizing Radiation Section, NMIJ/AIST, Tsukuba 305-8568 (Japan); Koyama, Y. [Ionizing Radiation Section, NMIJ/AIST, Tsukuba 305-8568 (Japan)

    2005-12-01

    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 {sup 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.

  9. [Intraocular lenses for the correction of refraction errors. Part II. Phakic posterior chamber lenses and refractive lens exchange with posterior chamber lens implantation].

    Science.gov (United States)

    Kohnen, T; Kasper, T; Terzi, E

    2005-11-01

    In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses which are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for posterior chamber lenses these are mainly cataract formation and pigment dispersion. RLE is preferable in cases of high ametropia in which the natural lens has lost its accommodative effect. The main complications for myopic RLA include retinal detachment, while hyperopic refractive lens exchange may be associated with surgical problems in the narrower anterior eye segment.

  10. Offshore Wind Technology Depth Zones

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Coastal bathymetric depth, measured in meters at depth values of: -30, -60, -900 Shallow Zone (0-30m): Technology has been demonstrated on a commercial scale at...

  11. Frenectomy with anterior lingual sulcoplasty for an implant-supported overdenture: A clinical report.

    Science.gov (United States)

    Perri de Carvalho, Paulo Sergio; Janjacomo, Luiz Antonio; Ponzoni, Daniela

    2016-04-01

    This clinical report describes the deepening of a patient's anterior mandibular lingual sulcus in combination with frenectomy and the use of an acrylic resin guiding device fixed to an osseointegrated dental implant to maintain the patency of the new sulcular depth.

  12. 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...

  13. 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...

  14. Anterior chest wall examination reviewed

    Directory of Open Access Journals (Sweden)

    F. Trotta

    2011-09-01

    Full Text Available Anterior chest wall involvement is not infrequently observed within inflammatory arthropaties, particularly if one considers seronegative spondiloarthritides and SAPHO syndrome. Physical examination is unreliable and conventional X-rays analysis is an unsatisfactory tool during diagnostic work-up of this region. Scintigraphic techniques yield informations both on the activity and on the anatomical extent of the disease while computerized tomography visualize the elementary lesions, such as erosions, which characterize the process. Moreover, when available, magnetic resonance imaging couple the ability to finely visualize such lesions with the possibility to show early alterations and to characterize the “activity” of the disease, presenting itself as a powerful tool both for diagnosis and follow-up. This review briefly shows the applications of imaging techniques for the evaluation of the anterior chest wall focusing on what has been done in the SAPHO syndrome which can be considered prototypical for this regional involvement since it is the osteo-articular target mainly affected by the disease.

  15. 原发性急性闭角型青光眼周边虹膜切除和滤过性手术前后眼前段结构参数对比分析%Anterior segment optical coherence tomography changes after iridectomy or trabeculectomy in angle-closure glaucoma

    Institute of Scientific and Technical Information of China (English)

    李媚; 刘杏; 钟毅敏; 曹丹; 杨晔; 曾阳发

    2011-01-01

    Objective To evaluate the changes in antenor segment configuration after peripheral iridectomy (PD or trabeculectomy (Trab) in acute primary angle closure glaucoma (APACG). Methods FiRy-seven eyes of 57 patients with APACG were successive collected. PI was performed to those patients with the clock hours of peripheral anterior synechiae (PAS) 6, while Trab was performed to those patients with the clock hours of PAS >6. Anterior segment optical coherence tomography (AS-OCT) examination was performed before and 3 months after PI/Trab to compare central anterior chamber depth (ACD), angle opening distance (AOD), trabecular iris area (TISA), angle recess area (ARA), anterior chamber width (ACW), anterior chamber volume (ACV) and crystalline lens rise (CLR). Results There were no differences in mean age (P 0.862) and male/female ratio (P=0.380) between the 2 groups. After surgery, AOD, TISA, ARA, ACA and ACV increased significantly (P <0.001~0.044), while no changes were found in ACD, ACW and CLR (P=0.102~0.609) in PI group. In Trab group, ACV increased significantly postoperation (P <0.001) while other parameters shown no changes. Conclusions Both surgery of PI and Trab can increase ACV; PI can improve the anterior angle parameters in APACG, but Trab surgery shows no changes of those parameters.%目的 观察原发性急性闭角型青光眼(acute primary angle closure glaucoma,APACG)周边虹膜切除(peripheral iridectomy,PI)和小梁切除术(Trabeculectomy,Trab)手术前后眼前段结构参数的改变.方法 临床病例对照研究.对2009年6~12月在中山大学眼科中心连续性收集57例57只眼APACG患者,周边虹膜粘连(peripheral anterior synechiae,PAS)范围≤6个钟点者行PI术,PAS范围>6个钟点者行小梁切除术,术前及术后3月行眼前段光学相干断层扫描仪(anterior segment optical coherence tomograph,AS-OCT)眼前段扫描.比较两组组内及组间术前及术后的中央前房深度(central anterior chamber

  16. Is biologic width of anterior and posterior teeth similar?

    Directory of Open Access Journals (Sweden)

    Amir Alireza Rasouli Ghahroudi

    2014-09-01

    Full Text Available The biologic width (BW includes attached epithelial cells and connective tissue attachment complex being very important in the periodontal health during prosthetic treatments as invading this zone can cause bone resorption and gingival recession. The present study investigated biologic width values in the normal periodontium in anterior and posterior teeth. 30 patients that referred from restorative department to periodontics department of Tehran University of medical sciences who need crown lengthening procedure on their teeth with no history of orthodontic, prosthodontic and periodontal treatment were randomly enrolled in this cross-sectional trial. Sulcus depths (SD as well as the distance between free gingival margin and the bone crest (FB of anterior and posterior teeth were measured by UNC-15 probe and compared. periodontium thickness was also assessed. The data were subjected to Student t test. Mean BW in the 43 anterior and 47 posterior teeth was measured and not significantly different (1.4651±0.39 mm vs. 1.6312±0.49 mm was observed; however, BW was significantly more in the teeth with thick periodontium compared to those with thin periodontium (1.703±0.5 vs. 1.408±0.35; P=0.002. BW not only is different in individuals but also could be dissimilar in different teeth and should be calculated independently prior to restorative treatments.

  17. Ion distributions in plane and cylindrical chambers.

    Science.gov (United States)

    Rosen, R; George, E P

    1975-11-01

    The ion chamber equations of Thomson include both ion recombination and space-charge terms. Neglecting the space-charge term, an exact solution is obtained for the ion densities across a plane ionization chamber. The method is extended to the cylindrical chamber, and examples are given of the expected ion distributions in both geometries. Current-voltage relationships are derived for both chambers and compared with those of other workers. If the space-charge term is retained, the ion chamber equations for both geometries are not soluble in closed form. The cylindrical chamber is considered and a computer solution is obtained for the ion distributions and current. Comparison with the nonspace-charge solution shows that while there is only a small difference in the current-voltage relationship, a significant difference can occur in the ion concentrations.

  18. Tests of anechoic chamber for aeroacoustics investigations

    Science.gov (United States)

    Palchikovskiy, V. V.; Bersenev, Yu. V.; Makashov, S. Yu.; Belyaev, I. V.; Korin, I. A.; Sorokin, E. V.; Khramtsov, I. V.; Kustov, O. Yu.

    2016-10-01

    The paper presents the results of qualification tests in the new anechoic chamber of Perm National Research Polytechnic University (PNRPU) built in 2014-2015 and evaluation of the chamber quality in aeroacoustic experiments. It describes design features of the chamber and its sound-absorption lining. The qualification tests were carried out with tonal and broadband noise sources in the frequency range 100 Hz - 20 kHz for two different cases of the source arrangement. In every case, measurements were performed in three directions by traverse microphones. Qualification tests have determined that in the chamber there is a free acoustic field within radius of 2 m for tonal noise and 3 m for broadband noise. There was also evaluated acoustic quality of the chamber by measurements of the jet noise and vortex ring noise. The results of the experiments demonstrate that PNRPU anechoic chamber allows the aeroacoustic measurements to be performed to obtain quantitative results.

  19. Positioning of anterior teeth in removable dentures

    Directory of Open Access Journals (Sweden)

    Strajnić Ljiljana

    2002-01-01

    Full Text Available Introduction The aim of this paper was to present methods of placement of artificial anterior teeth in edentulous individuals. The following review takes account of the majority of papers published during the last 100 years. The review has been divided into sections regarding the method used to determine the position of artificial anterior teeth. Geometric aspect Gysi (1895-1920 produced the first scientific theory about the position of artificial anterior teeth. Physiognomic theory The aim of this theory is to find the most natural position for artificial anterior teeth for each individual. Camper's "face angle" as a physiognomic criterion, has been introduced in papers of Wehrli (1961, Marxhors (1966, Tanzer (1968, Lombardi (1973. Esthetic aspect Important names in the field of dental esthetics are: Schön and Singer (1961, Arnheim (1965, Krajiček (1969, Tanzer (1968, Lombardi (1973, Goldstein (1976. They have introduced principles of visual aspects for selection of contours, dimension and position of artificial anterior teeth. Constitution aspect Flagg (1880, Williams (1913 and Hrauf (1957, 1958, have considered body constitution and individual characteristics regarding position of artificial anterior teeth. Physiological theory In 1971, Marxhors pointed to the fact that the position of artificial teeth corresponds with the function of the surrounding soft tissue and from the aspect of physiognomy as well. Phonetic aspect According to Silverman (1962 artificial anterior teeth are nearest when we pronounce the sound "S". Cephalometrical research Rayson (1970, Watson (1989, Strajnić Lj. (1999, Bassi F. (2001 have presented cephalometric radiographic analyses of natural anterior teeth compared with cephalometric radiographic analyses of artificial anterior teeth. A review of dental literature shows several factors suggesting modalities which should determine the position of artificial anterior teeth. Numerous methods have been designed for

  20. Incidental Anterior Cruciate Ligament Calcification: Case Report.

    Science.gov (United States)

    Hayashi, Hisami; Fischer, Hans

    2016-03-01

    The calcification of knee ligaments is a finding noted only in a handful of case reports. The finding of an anterior cruciate ligament calcification has been reported once in the literature. Comparable studies involving the posterior cruciate ligament, medial collateral ligament and an ossicle within the anterior cruciate ligament are likewise discussed in reports of symptomatic patients. We report a case of incidentally discovered anterior cruciate ligament calcification. We discuss the likely etiology and clinical implications of this finding.

  1. The ARGUS microvertex drift chamber

    Science.gov (United States)

    Michel, E.; Schmidt-Parzefall, W.; Appuhn, R. D.; Buchmüller, J.; Kolanoski, H.; Kreimeier, B.; Lange, A.; Siegmund, T.; Walther, A.; Edwards, K. W.; Fernholz, R. C.; Kapitza, H.; MacFarlane, D. B.; O'Neill, M.; Parsons, J. A.; Prentice, J. D.; Seidel, S. C.; Tsipolitis, G.; Ball, S.; Babaev, A.; Danilov, M.; Tichomirov, I.

    1989-11-01

    The ARGUS collaboration is currently building a new microvertex drift chamber (μVDC) as an upgrade of their detector. The μVDC is optimized for B-meson physics at DORIS energies. Important design features are minimal multiple scattering for low-momentum particles and three-dimensional reconstruction of decay vertices with equal resolutions in r- φ and r- z. Vertex resolutions of 15-25 μm are expected. Prototypes of the μVDC have been tested with different gas mixtures at various pressures. Spatial resolutions as small as 20 μm were obtained using CO 2/propane at 4 bar and DME at 1 bar. New readout electronics have been developed for the μVDC aiming at low thresholds for the TDC measurements. Employing a novel idea for noise and cross-talk suppression, which is based on a discrimination against short pulses, very low threshold settings are possible.

  2. The CAST Time Projection Chamber

    CERN Document Server

    Autiero, D; Cébrian, S; Carmona, J M; Chesi, Enrico Guido; Davenport, M; Delattre, M; Di Lella, L; Formenti, F; Gomez, H; Hasinoff, M; Irastorza, I G; Lakic, B; Luzón, G; Morales, J; Musa, L; Ortiz, A; Placci, A; Rodríguez, A; Ruz, J; Villar, J A; Zioutas, K

    2007-01-01

    One of the three X-ray detectors of the CAST experiment searching for solar axions is a Time Projection Chamber (TPC) with a multi-wire proportional counter (MWPC) as a readout structure. Its design has been optimized to provide high sensitivity to the detection of the low intensity X-ray signal expected in the CAST experiment. A low hardware threshold of 0.8 keV is safely set during normal data taking periods, and the overall efficiency for the detection of photons coming from conversion of solar axions is 62 %. Shielding has been installed around the detector, lowering the background level to 4.10 x 10^-5 counts/cm^2/s/keV between 1 and 10 keV. During phase I of the CAST experiment the TPC has provided robust and stable operation, thus contributing with a competitive result to the overall CAST limit on axion-photon coupling and mass.

  3. Free-Flow Open-Chamber Electrophoresis

    Science.gov (United States)

    Sharnez, Rizwan; Sammons, David W.

    1994-01-01

    Free-flow open-chamber electrophoresis variant of free-flow electrophoresis performed in chamber with open ends and in which velocity of electro-osmotic flow adjusted equal to and opposite mean electrophoretic velocity of sample. Particles having electrophoretic mobilities greater than mean mobility of sample particles move toward cathode, those with mobilities less move toward anode. Technique applied to separation of components of mixtures of biologically important substances. Sensitivity enhanced by use of tapered chamber.

  4. Vacuum Chamber for the Booster Bending Magnets

    CERN Multimedia

    1974-01-01

    To minimize eddy currents, induced by the rising magnetic field, the chamber was made from thin stainless steel of high specific electric resistance. For mechanical stength, it was corrugated in a hydro-forming process. The chamber is curved, to follow the beam's orbital path. Under vacuum, the chamber tends to staighten, the ceramic spacer along half of its length keeps it in place (see also 7402458).

  5. Bubble chamber: Omega production and decay

    CERN Multimedia

    1973-01-01

    This image is taken from one of CERN's bubble chambers and shows the decay of a positive kaon in flight. The decay products of this kaon can be seen spiraling in the magnetic field of the chamber. 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 has been heated to boiling point.

  6. Drift chamber tracking with neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Lindsey, C.S.; Denby, B.; Haggerty, H.

    1992-10-01

    We discuss drift chamber tracking with a commercial log VLSI neural network chip. Voltages proportional to the drift times in a 4-layer drift chamber were presented to the Intel ETANN chip. The network was trained to provide the intercept and slope of straight tracks traversing the chamber. The outputs were recorded and later compared off line to conventional track fits. Two types of network architectures were studied. Applications of neural network tracking to high energy physics detector triggers is discussed.

  7. Laser Welding Test Results with Gas Atmospheres in Welding Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Joung, Chang-Young; Hong, Jin-Tae; Ahn, Sung-Ho; Heo, Sung-Ho; Jang, Seo-Yun; Yang, Tae-Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The weld beads of specimens welded under identical conditions in the helium and argon gas were cleaner, more regular, and steadier than those in a vacuum. The penetration depth of the FZ in the vacuum was much deeper than those in the helium and argon gas. To measure the irradiation properties of nuclear fuel in a test reactor, a nuclear fuel test rod instrumented with various sensors must be fabricated with assembly processes. A laser welding system to assemble the nuclear fuel test rod was designed and fabricated to develop various welding technologies of the fuel test rods to joint between a cladding tube and end-caps. It is an air-cooling optical fiber type and its emission modes are a continuous (CW) mode of which the laser generates continuous emission, and pulse (QCW) mode in which the laser internally generates sequences of pulses. We considered the system welding a sample in a chamber that can weld a specimen in a vacuum and inert gas atmosphere, and the chamber was installed on the working plate of the laser welding system. In the chamber, the laser welding process should be conducted to have no defects on the sealing area between a cladding tube and an end-cap.

  8. Severe anterior uveitis associated with idiopathic dacryoadenitis in diabetes mellitus patient

    Directory of Open Access Journals (Sweden)

    Takahashi YY

    2011-05-01

    Full Text Available Yasuhiro Takahashi¹, Hirohiko Kakizaki¹, Akihiro Ichinose², Masayoshi Iwaki¹¹Department of Ophthalmology, Aichi Medical University, Nagakute, Aichi, Japan; ²Department of Plastic Surgery, Kobe University, Kobe, Hyogo, JapanAbstract: A 38-year-old woman with diabetes mellitus complained of acute visual loss in the left eye (20/200 and swollen left upper eyelid. Slit lamp examination of the left eye revealed ciliary injection, posterior synechia iritis, numerous inflammatory cells, and fibrin exudates in the anterior chamber. T1-weighted enhanced magnetic resonance imaging demonstrated left lacrimal gland enhancement with inflammatory spread to the left anterior ocular segment. Blood examination showed increased blood sugar but the other components were within normal limits. The patient was treated with steroid pulse therapy (methylprednisolone 1 g/day × 3 days under a blood sugar control regimen in consultation with an endocrinologist, after which additional peribulbar injection of triamcinolone acetonide (40 mg was performed. Resolution of the anterior uveitis and the dacryoadenitis was obtained after 2 months and there was no recurrence 1 year after the therapy. This is a rare case of severe anterior uveitis caused by idiopathic dacryoadenitis in a patient with diabetes mellitus.Keywords: anterior uveitis, idiopathic dacryoadenitis, diabetes mellitus, magnetic resonance imaging, steroid

  9. Excitatory and inhibitory effects of prolactin release activated by nerve stimulation in rat anterior pituitary

    Directory of Open Access Journals (Sweden)

    Gao Li-Zhi

    2009-12-01

    Full Text Available Abstract Background A series of studies showed the presence of substantial amount of nerve fibers and their close relationship with the anterior pituitary gland cells. Our previous studies have suggested that aside from the classical theory of humoral regulation, the rat anterior pituitary has direct neural regulation on adrenocorticotropic hormone release. In rat anterior pituitary, typical synapses are found on every type of the hormone-secreting cells, many on lactotrophs. The present study was aimed at investigating the physiological significance of this synaptic relationship on prolactin release. Methods The anterior pituitary of rat was sliced and stimulated with electrical field in a self-designed perfusion chamber. The perfusate was continuously collected in aliquots and measured by radioimmunoassay for prolactin levels. After statistic analysis, differences of prolactin concentrations within and between groups were outlined. Results The results showed that stimulation at frequency of 2 Hz caused a quick enhancement of prolactin release, when stimulated at 10 Hz, prolactin release was found to be inhibited which came slower and lasted longer. The effect of nerve stimulation on prolactin release is diphasic and frequency dependent. Conclusions The present in vitro study offers the first physiological evidence that stimulation of nerve fibers can affect prolactin release in rat anterior pituitary. Low frequency stimulation enhances prolactin release and high frequency mainly inhibits it.

  10. Jupiter Clouds in Depth

    Science.gov (United States)

    2000-01-01

    [figure removed for brevity, see original site] 619 nm [figure removed for brevity, see original site] 727 nm [figure removed for brevity, see original site] 890 nmImages from NASA's Cassini spacecraft using three different filters reveal cloud structures and movements at different depths in the atmosphere around Jupiter's south pole.Cassini's cameras come equipped with filters that sample three wavelengths where methane gas absorbs light. These are in the red at 619 nanometer (nm) wavelength and in the near-infrared at 727 nm and 890 nm. Absorption in the 619 nm filter is weak. It is stronger in the 727 nm band and very strong in the 890 nm band where 90 percent of the light is absorbed by methane gas. Light in the weakest band can penetrate the deepest into Jupiter's atmosphere. It is sensitive to the amount of cloud and haze down to the pressure of the water cloud, which lies at a depth where pressure is about 6 times the atmospheric pressure at sea level on the Earth). Light in the strongest methane band is absorbed at high altitude and is sensitive only to the ammonia cloud level and higher (pressures less than about one-half of Earth's atmospheric pressure) and the middle methane band is sensitive to the ammonia and ammonium hydrosulfide cloud layers as deep as two times Earth's atmospheric pressure.The images shown here demonstrate the power of these filters in studies of cloud stratigraphy. The images cover latitudes from about 15 degrees north at the top down to the southern polar region at the bottom. The left and middle images are ratios, the image in the methane filter divided by the image at a nearby wavelength outside the methane band. Using ratios emphasizes where contrast is due to methane absorption and not to other factors, such as the absorptive properties of the cloud particles, which influence contrast at all wavelengths.The most prominent feature seen in all three filters is the polar stratospheric haze that makes Jupiter bright near the pole

  11. Engineering verification of the biomass production chamber

    Science.gov (United States)

    Prince, R. P.; Knott, W. M., III; Sager, J. C.; Jones, J. D.

    1992-01-01

    The requirements for life support systems, both biological and physical-chemical, for long-term human attended space missions are under serious study throughout NASA. The KSC 'breadboard' project has focused on biomass production using higher plants for atmospheric regeneration and food production in a special biomass production chamber. This chamber is designed to provide information on food crop growth rate, contaminants in the chamber that alter plant growth requirements for atmospheric regeneration, carbon dioxide consumption, oxygen production, and water utilization. The shape and size, mass, and energy requirements in relation to the overall integrity of the biomass production chamber are under constant study.

  12. Precision Radio Frequency Anechoic Chamber Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Performs measurements and calibration of antennas for satellites and aircraft or groundbased systems. The chamber is primarily used for optimizing antenna...

  13. The Mark II Vertex Drift Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, J.P.; Baggs, R.; Fujino, D.; Hayes, K.; Hoard, C.; Hower, N.; Hutchinson, D.; Jaros, J.A.; Koetke, D.; Kowalski, L.A.

    1989-03-01

    We have completed constructing and begun operating the Mark II Drift Chamber Vertex Detector. The chamber, based on a modified jet cell design, achieves 30 {mu}m spatial resolution and <1000 {mu}m track-pair resolution in pressurized CO{sub 2} gas mixtures. Special emphasis has been placed on controlling systematic errors including the use of novel construction techniques which permit accurate wire placement. Chamber performance has been studied with cosmic ray tracks collected with the chamber located both inside and outside the Mark II. Results on spatial resolution, average pulse shape, and some properties of CO{sub 2} mixtures are presented. 10 refs., 12 figs., 1 tab.

  14. Two-chambered right ventricle resulting from aberrant muscle bundles: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Lim, T. H.; Ko, K. H.; Im, C. K.; Han, M. C.; Chi, J. G [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1979-12-15

    The 'Two-chambered right ventricle' is a rare, but unique congenital cardiac anomaly characterized by subdivision of the right ventricle into proximal high pressure chamber and distal low pressure chamber by hypertrophied aberrant muscle bundles. The aberrant muscle bundles traverse the right ventricle from the region of crista supraventricular is to the lower part of the anterior wall of the right ventricle. The ' Two-chambered right ventricle' is usually associated with other congenital cardiac anomalies such as ventricular septal defect, pulmonary valvular stenosis, etc. Therefore this anomaly could be mistakenly diagnosed as Tetralogy of Fallot or isolated interventricular septal defect. The need to separate this entity from other types of infundibular stenosis is emphasized because of the important surgical implications. Authors recently experienced a case of the {sup T}wo-chambered right ventricle' resulting from aberrant muscle bundles, that are associated with other cardiac anomalies i.e., pulmonary valvular stenosis, aysplastic tricuspid valve with regurgitation and partial anomalous pulmonary venous return to the right atrium. Here we present the findings of E.K.G., cardiac catheterization, simple chest pa, cine-right ventriculography, and autopsy together with a review of related articles.

  15. A knotless, one-haptic fixation of posterior chamber intraocular lenses: one-year results

    Institute of Scientific and Technical Information of China (English)

    Pipat; Kongsap

    2015-01-01

    AIM: To assess the results of a modified technique for scleral fixation of a posterior chamber intraocular lens(IOL) in eyes which had deficient of posterior capsular support.METHODS: This retrospective study was comprised of ten patients with deficient posterior capsular support who underwent one-haptic fixation of posterior chamber IOLs, between February 2010 and October 2011. IOL as implanted with one haptic supported on the capsular remnant and the other haptic drawn into the sulcus by anchoring suture without a knot. All patients were evaluated for pre- and postoperative visual acuity, lens centration, intra-and postoperative complications.RESULTS: A knotless, one-haptic fixation of posterior chamber IOLs has successfully been performed on ten eyes. All cases had inadequate capsular support(i.e. a capsular tear ranged from 5 to 7 clock hours). The average age was 74.25 ±8.87y(SD). The average postoperative uncorrected visual acuity was 0.51 log MAR.Complications included hyphema in one eye, a mild inflammatory reaction in the anterior chamber in two eyes, and a transient rise in IOP in one eye. Neither IOL tilt nor dislocation was observed and there were no later complications.CONCLUSION: In the presence of insufficient capsular support, a knotless, one-haptic fixation of posterior chamber IOLs is a safe and viable option which reduces the operation time, and minimizes postoperative suture-related complications.

  16. Toxic Anterior Segment Syndrome (TASS

    Directory of Open Access Journals (Sweden)

    Özlem Öner

    2011-12-01

    Full Text Available Toxic anterior segment syndrome (TASS is a sterile intraocular inflammation caused by noninfectious substances, resulting in extensive toxic damage to the intraocular tissues. Possible etiologic factors of TASS include surgical trauma, bacterial endotoxin, intraocular solutions with inappropriate pH and osmolality, preservatives, denatured ophthalmic viscosurgical devices (OVD, inadequate sterilization, cleaning and rinsing of surgical devices, intraocular lenses, polishing and sterilizing compounds which are related to intraocular lenses. The characteristic signs and symptoms such as blurred vision, corneal edema, hypopyon and nonreactive pupil usually occur 24 hours after the cataract surgery. The differential diagnosis of TASS from infectious endophthalmitis is important. The main treatment for TASS formation is prevention. TASS is a cataract surgery complication that is more commonly seen nowadays. In this article, the possible underlying causes as well as treatment and prevention methods of TASS are summarized. (Turk J Oph thal mol 2011; 41: 407-13

  17. Evaluation of Depth of Field for depth perception in DVR

    KAUST Repository

    Grosset, A.V.Pascal

    2013-02-01

    In this paper we present a user study on the use of Depth of Field for depth perception in Direct Volume Rendering. Direct Volume Rendering with Phong shading and perspective projection is used as the baseline. Depth of Field is then added to see its impact on the correct perception of ordinal depth. Accuracy and response time are used as the metrics to evaluate the usefulness of Depth of Field. The onsite user study has two parts: static and dynamic. Eye tracking is used to monitor the gaze of the subjects. From our results we see that though Depth of Field does not act as a proper depth cue in all conditions, it can be used to reinforce the perception of which feature is in front of the other. The best results (high accuracy & fast response time) for correct perception of ordinal depth occurs when the front feature (out of the two features users were to choose from) is in focus and perspective projection is used. © 2013 IEEE.

  18. SU-E-T-443: Developmental Technique for Proton Pencil Beam Measurements: Depth Dose

    Energy Technology Data Exchange (ETDEWEB)

    Arjomandy, B; Lee, T; Schultz, T; Hsi, W; Park, S [McLaren Cancer Institute, Flint, MI (United States)

    2014-06-01

    Purpose: Measurements of depth dose distribution (DDD) of pencil beam in proton therapy can be challenging and time consuming. We have developed a technique that uses two Bragg peak chambers to expedite these measurements with a high accuracy. Methods and Material: We used a PTW water tank and two PTW 10.5 cm3 Bragg peak chambers; one as a field chamber and the other as a reference chamber to measure DDDs for 100–250 MeV proton pencil beams. The reference chamber was positioned outside of the water tank upstream with respect to field chamber. We used Geant4 Monte Carlo Simulation (MCS) to model the ProTom proton beam to generate DDDs. The MCS generated DDDs were used to account for halo effects of proton pencil beam that are not measureable with Bragg peak chambers. We also used PTW PEAKFINDER to measure DDDs for comparison purpose. Results: We compared measured and MCS DDDs with Continuous Slowing Down Approximation (CSDA) ranges to verify the range of proton beams that were supplied by the manufacturer. The agreements between all DDD with respect to CSDA were within ±0.5 mm. The WET for Bragg peak chamber for energies between 100–250 MeV was 12.7 ± 0.5 mm. The correction for halo effect was negligible below 150 MeV and was in order of ∼5-10% for 150–250 MeV. Conclusion: Use of Bragg Peak chamber as a reference chamber can facilitate DDD measurements in proton pencil beam with a high accuracy. Some corrections will be required to account for halo effect in case of high energy proton beams due to physical size of chamber.

  19. Mild toxic anterior segment syndrome mimicking delayed onset toxic anterior segment syndrome after cataract surgery

    Directory of Open Access Journals (Sweden)

    Su-Na Lee

    2014-01-01

    Full Text Available Toxic anterior segment syndrome (TASS is an acute sterile postoperative anterior segment inflammation that may occur after anterior segment surgery. I report herein a case that developed mild TASS in one eye after bilateral uneventful cataract surgery, which was masked during early postoperative period under steroid eye drop and mimicking delayed onset TASS after switching to weaker steroid eye drop.

  20. Optimization of the depth resolution for deuterium depth profiling up to large depths

    Science.gov (United States)

    Wielunska, B.; Mayer, M.; Schwarz-Selinger, T.

    2016-11-01

    The depth resolution of deuterium depth profiling by the nuclear reaction D(3He,p)α is studied theoretically and experimentally. General kinematic considerations are presented which show that the depth resolution for deuterium depth profiling using the nuclear reaction D(3He,p)α is best at reaction angles of 0° and 180° at all incident energies below 9 MeV and for all depths and materials. In order to confirm this theoretical prediction the depth resolution was determined experimentally with a conventional detector at 135° and an annular detector at 175.9°. Deuterium containing thin films buried under different metal cover layers of aluminum, molybdenum and tungsten with thicknesses in the range of 0.5-11 μm served as samples. For all materials and depths an improvement of the depth resolution with the detector at 175.9° is achieved. For tungsten as cover layer a better depth resolution up to a factor of 18 was determined. Good agreement between the experimental results and the simulations for the depth resolution is demonstrated.

  1. Resistive wall heating due to image current on the beam chamber for a superconducting undulator.

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. H. (Accelerator Systems Division (APS))

    2012-03-27

    The image-current heating on the resistive beam chamber of a superconducting undulator (SCU) was calculated based on the normal and anomalous skin effects. Using the bulk resistivity of copper for the beam chamber, the heat loads were calculated for the residual resistivity ratios (RRRs) of unity at room temperature to 100 K at a cryogenic temperature as the reference. Then, using the resistivity of the specific aluminum alloy 6053-T5, which will be used for the SCU beam chamber, the heat loads were calculated. An electron beam stored in a storage ring induces an image current on the inner conducting wall, mainly within a skin depth, of the beam chamber. The image current, with opposite charge to the electron beam, travels along the chamber wall in the same direction as the electron beam. The average current in the storage ring consists of a number of bunches. When the pattern of the bunched beam is repeated according to the rf frequency, the beam current may be expressed in terms of a Fourier series. The time structure of the image current is assumed to be the same as that of the beam current. For a given resistivity of the chamber inner wall, the application ofthe normal or anomalous skin effect will depend on the harmonic numbers of the Fourier series of the beam current and the temperature of the chamber. For a round beam chamber with a ratius r, much larger than the beam size, one can assume that the image current density as well as the density square, may be uniform around the perimeter 2{pi}r. For the SCU beam chamber, which has a relatively narrow vertical gap compared to the width, the effective perimeter was estimated since the heat load should be proportional to the inverse of the perimeter.

  2. Anterior urethral diverticulum: A rare presentation

    Directory of Open Access Journals (Sweden)

    Annavarupu Gopalkrishna

    2016-01-01

    Full Text Available Congenital anomalies of the urogenital tract are the most common anomalies found in the foetus, neonates and infants, but anterior urethral valves and diverticula are rare. Here, we present a case with congenital anterior urethral diverticulum associated with patent ductus arteriosus and polydactyly.

  3. Totally thrombosed giant anterior communicating artery aneurysm

    Directory of Open Access Journals (Sweden)

    V R Roopesh Kumar

    2015-01-01

    Full Text Available Giant anterior communicating artery aneurysmsarerare. Apatient presented with visual dysfunction, gait ataxia and urinary incontinence. MRI showed a giant suprasellar mass.At surgery, the lesion was identified as being an aneurysm arising from the anterior communicating artery.The difficulty in preoperative diagnosis and relevant literature are reviewed.

  4. Anterior segment complications of retinal photocoagulation.

    Science.gov (United States)

    Kanski, J J

    1975-03-01

    Seven patients had anterior segment complications following xenon arc retinal photocoagulation. Irreversible keratopathy was induced in two cases; all patients showed evidence of iris injury. The absorption of radiation by the iris was considered the main factor in producing overheating of the anterior segment.

  5. Anterior cervical hypertrichosis: a sporadic case.

    Science.gov (United States)

    Bostan, Sezen; Yaşar, Şirin; Serdar, Zehra Aşiran; Gizlenti, Sevda

    2016-03-01

    Anterior cervical hypertrichosis is a very rare form of primary localized hypertrichosis. It consists of a tuft of terminal hair on the anterior neck just above the laryngeal prominence. The etiology is still unknown. In this article, we reported a 15-year-old female patient who presented to our clinic with a complaint of hypertrichosis on the anterior aspect of the neck for the last five years. Her past medical history revealed no pathology except for vesicoureteral reflux. On the basis of clinical presentation, our patient was diagnosed with anterior cervical hypertrichosis and she was considered to be a sporadic case due to lack of other similar cases in familial history. To date, 33 patients with anterior cervical hypertrichosis have been reported. Anterior cervical hypertrichosis can be associated with other abnormalities, but it frequently presents as an isolated defect (70%). The association of vesicoureteral reflux and anterior cervical hypertrichosis which was observed in our patient might be coincidental. So far, no case of anterior cervical hypertrichosis associated with vesicoureteral reflux has been reported in the literature.

  6. An ionization chamber with magnetic levitated electrodes

    CERN Document Server

    Kawaguchi, T

    1999-01-01

    A new type of ionization chamber which has magnetically levitated electrodes has been developed. The electrodes are supplied voltages for the repelling of ions by a battery which is also levitated with the electrodes. The characteristics of this ionization chamber are investigated in this paper.

  7. HVAC&R Equipment Environmental Chambers

    Data.gov (United States)

    Federal Laboratory Consortium — Description:Large "Truck" ChamberThe large "truck" chamber provides controlled air conditions from -7 °C (20 °F) to 65 °C (150 °F).Air-Conditioner and Heat Pump Test...

  8. Supersonic Jet Interactions in a Plenum Chamber

    Directory of Open Access Journals (Sweden)

    K. M. Venugopal

    2004-07-01

    Full Text Available Understanding thè supersonic jet interactions in a plenum chamber is essential for thè design of hot launch systems. Static tests were conducted in a small-scale rocket motor ioaded with a typical nitramine propellaiit to produce a nozzle exit Mach number of 3. This supersonic jet is made to interact with plenum chambers having both open and closed sides. The distance between thè nozzle exit and thè back piate of plenum chamber are varied from 2. 5 to 7. 0 times thè nozzle exit diameter. The pressure rise in thè plenum chamber was measured using pressure transducers mounted at different locatìons. The pressure-time data were analysed to obtain an insight into thè flow field in thè plenum chamber. The maximum pressure exerted on thè back piate of plenum chamber is about 25-35 per cent. of thè maximum stagnation pressure developed in thè rocket motor. Ten static tests were carried out to obtain thè effect of axial distance between thè nozzle exit and thè plenum chamber back piate, and stagnation pressure in thè rocket motoron thè flow field in thè open-sided and closed-sided plenum chambers configurations.

  9. 21 CFR 866.2120 - Anaerobic chamber.

    Science.gov (United States)

    2010-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2120 Anaerobic chamber. (a) Identification. An anaerobic chamber is a device intended for medical purposes to maintain an anaerobic...

  10. ME1/1 Cathode Strip Chambers

    CERN Document Server

    Erchov, Yu V; Kamenev, Alexey; Karjavin, Vladimir; Khabarov, Serguei; Moissenz, P V; Moissenz, K P; Movchan, Sergey; Perelygin, Victor; Vassiliev, S E; Zarubin, Anatoli; Tchekhovski, V A

    2008-01-01

    The 76 innermost ME1/1 cathode strip chambers (CSC) of the CMS Experiment were designed and produced in Dubna. The chambers have been installed in the detector and commissioning has been completed. This paper describes the design of the CSCs, their main mechanical parameters and read-out electronics, and the results of tests with cosmic-ray muons.

  11. Results from the MAC Vertex chamber

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, H.N.

    1987-05-01

    The design, construction, and performance characteristics of a high precision gaseous drift chamber made of thin walled proportional tubes are described. The device achieved an average spatial resolution of 45 ..mu..m in use for physics analysis with the MAC detector. The B-lifetime result obtained with this chamber is discussed.

  12. Raymond J. Chambers--A Personal Reflection

    Science.gov (United States)

    Gaffikin, Michael

    2012-01-01

    This paper is presented as a tribute to Raymond J. Chambers. As its title suggests, it is a personal reflection through the eyes of someone who worked closely with him over a period of 10 years during a latter part of his career, and who completed a doctoral thesis with aspects of the work of Chambers as its subject. During this time, author…

  13. Effect of coronary occlusion during percutaneous transluminal angioplasty in humans on left ventricular chamber stiffness and regional diastolic pressure-radius relations

    NARCIS (Netherlands)

    W. Wijns (William); P.W.J.C. Serruys (Patrick); C.J. Slager (Cornelis); J. Grimm; H.P. Krayenbuehl; P.G. Hugenholtz (Paul); O.M. Hess (Otto)

    1986-01-01

    textabstractThe effect of repeated (3 to 10 second) and transient (15 to 75 second) abrupt coronary occlusion on the global and regional chamber stiffness was studied in nine patients undergoing angioplasty of a single proximal left anterior descending coronary artery stenosis. The left ventricular

  14. 青光眼暗室激发试验的眼前节相关因素分析%The correlative factors of darkroom provocative test in anterior segment parameters

    Institute of Scientific and Technical Information of China (English)

    王忠浩; 李媚; 蔡小于; 梁轩伟; 刘杏

    2013-01-01

    目的 分析房角狭窄患者暗室激发试验阳性者的相关眼前节结构参数.方法 回顾性系列病例研究.分析260例房角狭窄患者的暗室试验结果和超声生物显微镜(UBM)眼前节结构参数.其中男性36例,女性224例,平均年龄(59.6±9.3)岁.眼前节结构参数包括前房深度(ACD)、瞳孔直径(PD)、晶状体矢高(LV)、周边虹膜厚度(IT)、虹膜膨隆度(IC)、房角开放距离(AOD)、小梁网睫状突夹角(TCPA)及房角接触性关闭的象限数(NPAC).用单因素和多因素Logistic回归分析青光眼暗室激发试验阳性的相关因素.结果 260例房角狭窄者青光眼暗室激发试验的阳性率为27.3% (71/206),男性阳性率(41.7%,15/36)大于女性(25.0%,56/224),差异有统计学意义(x2=4.340,P=0.037).单因素分析表明,男性(OR =2.14)、AOD(OR=0.98)、IT(OR=1.68)、NPAC(OR=2.24)是暗室试验阳性的相关因素;多因素Logistic回归分析表明,IT(OR=1.47)、NPAC(OR=1.70)是暗室试验阳性的独立相关因素.结论 房角和虹膜参数与房角狭窄者的青光眼暗室激发试验阳性结果相关,IT和NPAC是暗室激发试验阳性的独立相关因素.%Objective To investigate the correlative anterior segment parameters of positive darkroom provocative test in patients with narrow anterior chamber angles.Methods It was a retrospective case series study.Two hundred and sixty patients [36 males and 224 females,mean age (59.6 ± 9.3) years] with narrow anterior chamber angles underwent darkroom provocative test and UBM scan were analyzed retrospectively.Anterior segment parameters including anterior chamber depth (ACD),pupil diameter (PD),lens vault (LV),peripheral iris thickness (IT),iris convex (IC),anterior chamber angle open distance (AOD),trabecular-meshwork ciliary process angle (TCPA) and the number of appositional angle closure (NPAC) were quantitatively analyzed.Correlative factors of positive results were analysis by both single factor and multiple

  15. Chordal geometry determines the shape and extent of systolic anterior mitral motion: in vitro studies.

    Science.gov (United States)

    Cape, E G; Simons, D; Jimoh, A; Weyman, A E; Yoganathan, A P; Levine, R A

    1989-05-01

    In patients with hypertrophic cardiomyopathy, the mitral valve moves anteriorly and assumes a unique shape, with mitral-septal contact centrally and preserved valve orifice area laterally. This shape is not clearly predicted by the Venturi mechanism, which stresses flow above the valve as opposed to changes intrinsic to the valve. On the other hand, it has been suggested that displacement of the papillary muscles anteriorly and toward one another, as observed in this disease, can promote anterior mitral valve motion and produce this unusual shape. The purpose of this in vitro study was to test the hypotheses that anterior motion of a membrane in a flow field can be generated by altering the distribution or effectiveness of chordal tension tethering the membrane, and that the shape achieved by this membrane depends on the geometry of chordal tension. Accordingly, a horizontal leaflet mounted in a flow chamber was attached by chords at its distal end to a series of upstream screws. Chordal tension could be varied by turning the screws or redirected by shifting the screws anteriorly. Anterior leaflet motion having the same unusual configuration seen in patients was reproduced by decreasing central chordal restraint while tension on the leaflet edges was maintained. Directing chordal tension anteriorly caused greater degrees of anterior motion at earlier stages in the release of chordal restraint; increased flow rate had a similar but less marked effect. These studies suggest that primary geometric alterations in the papillary-mitral apparatus can play an important role in determining the presence and geometry of systolic anterior mitral motion. The nature of these alterations suggests a role for anterior and inward papillary muscle displacement in promoting such motion. The geometric factors embodied in this model can explain many observed features of this motion not adequately explained by the Venturi effect, such as early systolic onset and the importance of a

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

    Directory of Open Access Journals (Sweden)

    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.

  17. The LVD tracking system chambers

    Energy Technology Data Exchange (ETDEWEB)

    Anzivino, G.; Benvenuto, P.; Bianco, S.; Casaccia, R.; Dulach, B.; Fabbri, D.; Fabbri, F.L.; Gatta, M.; Giardoni, M.; Laakso, I.; Lindozzi, M.; Passamonti, L.; Russo, V.; Sarwar, S.; Sensolini, G.; Ventura, M.; Votano, L.; Zallo, A. (INFN, Lab. Nazionali di Frascati, Rome (Italy)); Mencarini, D. (Univ. Bologna (Italy), INFN, Bologna (Italy)); Pallante, E. (Univ. Rome-1 (Italy)); Aftab, Z.; Ali, M.M.; Chen, K.; Chen, R.; Cong, S.; Cui, X.; Ding, H.; Gao, B.; Li, Y.; Lu, L.; Minhas, B.K.; Shi, Z.; Shah, A.R.; Sun, Y.; Zhou, X. (ICSC World Lab., Lausanne (Switzerland))

    1993-06-01

    The LVD detector can be defined as an underground observatory with the main objectives of studying neutrinos from stellar collapse and searching for point-like sources of gammas and neutrinos of very high energy. This multipurpose apparatus is being installed in hall A of the Gran Sasso Laboratory at a vertical depth of 3600 m.w.e. It consists of a large volume of liquid scintillator divided into modules and of a tracking system made of layers of streamer tubes. (orig./HSI).

  18. The SAMURAI Time Projection Chamber

    Science.gov (United States)

    Dye, Steven

    2011-10-01

    The SAMURAI Time Projection Chamber (TPC) will be used to study particle collisions by colliding a beam of particles with a stationary gas which will be contained in a field cage inside the TPC. When the beam collides with the gas, charged particles are accelerated into the pad plane by an electric field. The paths of these particles will be curved by a magnetic field created by the SAMURAI magnet at the RIKEN facility in Japan. The charged particles will then collide with the pad plane which will be located on the bottom of the TPC. The pad plane will take these collisions and create electrical signals and send them to supporting electronics where the data can be interpreted. The TPC will be used to help determine the Equation of State for asymmetric nuclear matter. Measurements of neutron, proton, 3H and 3He flow will be taken with the NEBULA array which consists of nebula scintillators. The poster will contain information on the laser calibration system and the electronics that will be used for the TPC. The electronics used are the same electronics used in the STAR TPC experiment.

  19. The CAST time projection chamber

    Science.gov (United States)

    Autiero, D.; Beltrán, B.; Carmona, J. M.; Cebrián, S.; Chesi, E.; Davenport, M.; Delattre, M.; Di Lella, L.; Formenti, F.; Irastorza, I. G.; Gómez, H.; Hasinoff, M.; Lakic, B.; Luzón, G.; Morales, J.; Musa, L.; Ortiz, A.; Placci, A.; Rodrigurez, A.; Ruz, J.; Villar, J. A.; Zioutas, K.

    2007-06-01

    One of the three x-ray detectors of the CERN Axion Solar Telescope (CAST) experiment searching for solar axions is a time projection chamber (TPC) with a multi-wire proportional counter (MWPC) as a readout structure. Its design has been optimized to provide high sensitivity to the detection of the low intensity x-ray signal expected in the CAST experiment. A low hardware threshold of 0.8 keV is set to a safe level during normal data taking periods, and the overall efficiency for the detection of photons coming from conversion of solar axions is 62%. Shielding has been installed around the detector, lowering the background level to 4.10 × 10-5 counts cm-2 s-1 keV-1 between 1 and 10 keV. During phase I of the CAST experiment the TPC has provided robust and stable operation, thus contributing with a competitive result to the overall CAST limit on axion photon coupling and mass.

  20. Positioning of a plane-parallel ionization chamber in clinical electron beams and the impact on perturbation factors.

    Science.gov (United States)

    Zink, K; Wulff, J

    2009-04-21

    Current dosimetry protocols recommend the use of plane-parallel ionization chambers for the dosimetry of clinical electron beams. The necessary perturbation corrections p(wall) and p(cav) are assumed to be unity, independent of the depth of measurement and the energy of the primary electrons. To verify these assumptions detailed Monte Carlo studies of a Roos chamber in clinical electron beams with energies in the range of 6-21 MeV are performed at different depths in water and analyzed in terms of Spencer-Attix cavity theory. Separate simulations for the perturbation corrections p(wall) and p(cav) indicate quite different properties of both correction factors with depth. Dose as well as fluence calculations show a nearly depth-independent wall correction factor for a shift of the Roos chamber Deltaz = -0.017 cm toward the focus. This value is in good agreement with the positioning recommendation given in all dosimetry protocols. Regarding the fluence perturbation p(cav) the simulation of the electron fluence inside the air cavity in comparison to water unambiguously reveals an in-scattering of low energy electrons, despite the fact, that the cavity is 'well guarded'. For depths beyond the reference depth z(ref) this effect is superimposed by an increased loss of primary electrons from the beam resulting in p(cav) > 1. This effect is largest for low electron energies but present for all electron energies involved in this study. Based on the different depth dependences of p(wall) and p(cav) it is possible to choose a chamber shift Deltaz in a way to minimize the depth dependence of the overall perturbation factor p. For the Roos chamber this shift is Deltaz = -0.04 cm independent of electron energy.

  1. Positioning of a plane-parallel ionization chamber in clinical electron beams and the impact on perturbation factors

    Energy Technology Data Exchange (ETDEWEB)

    Zink, K; Wulff, J [Institut fuer Medizinische Physik und Strahlenschutz-IMPS, University of Applied Sciences Giessen-Friedberg, Wiesenstr. 14, D-35390 Giessen (Germany)], E-mail: klemens.zink@tg.fh-giessen.de

    2009-04-21

    Current dosimetry protocols recommend the use of plane-parallel ionization chambers for the dosimetry of clinical electron beams. The necessary perturbation corrections p{sub wall} and p{sub cav} are assumed to be unity, independent of the depth of measurement and the energy of the primary electrons. To verify these assumptions detailed Monte Carlo studies of a Roos chamber in clinical electron beams with energies in the range of 6-21 MeV are performed at different depths in water and analyzed in terms of Spencer-Attix cavity theory. Separate simulations for the perturbation corrections p{sub wall} and p{sub cav} indicate quite different properties of both correction factors with depth. Dose as well as fluence calculations show a nearly depth-independent wall correction factor for a shift of the Roos chamber {delta}z = -0.017 cm toward the focus. This value is in good agreement with the positioning recommendation given in all dosimetry protocols. Regarding the fluence perturbation p{sub cav} the simulation of the electron fluence inside the air cavity in comparison to water unambiguously reveals an in-scattering of low energy electrons, despite the fact, that the cavity is 'well guarded'. For depths beyond the reference depth z{sub ref} this effect is superimposed by an increased loss of primary electrons from the beam resulting in p{sub cav} > 1. This effect is largest for low electron energies but present for all electron energies involved in this study. Based on the different depth dependences of p{sub wall} and p{sub cav} it is possible to choose a chamber shift {delta}z in a way to minimize the depth dependence of the overall perturbation factor p. For the Roos chamber this shift is {delta}z = -0.04 cm independent of electron energy.

  2. Indexing Depth and Retrieval Effectiveness

    Science.gov (United States)

    Seely, Barbara J.

    1972-01-01

    There are six major studies of the effect of indexing depth on retrieval performance. They differ in purpose, methodology, measures, indexing language, field of study, and data base--nevertheless, all have found depth of indexing to have the same effect upon information retrieval. (13 references) (Author/NH)

  3. Metal detector depth estimation algorithms

    Science.gov (United States)

    Marble, Jay; McMichael, Ian

    2009-05-01

    This paper looks at depth estimation techniques using electromagnetic induction (EMI) metal detectors. Four algorithms are considered. The first utilizes a vertical gradient sensor configuration. The second is a dual frequency approach. The third makes use of dipole and quadrapole receiver configurations. The fourth looks at coils of different sizes. Each algorithm is described along with its associated sensor. Two figures of merit ultimately define algorithm/sensor performance. The first is the depth of penetration obtainable. (That is, the maximum detection depth obtainable.) This describes the performance of the method to achieve detection of deep targets. The second is the achievable statistical depth resolution. This resolution describes the precision with which depth can be estimated. In this paper depth of penetration and statistical depth resolution are qualitatively determined for each sensor/algorithm. A scientific method is used to make these assessments. A field test was conducted using 2 lanes with emplaced UXO. The first lane contains 155 shells at increasing depths from 0" to 48". The second is more realistic containing objects of varying size. The first lane is used for algorithm training purposes, while the second is used for testing. The metal detectors used in this study are the: Geonics EM61, Geophex GEM5, Minelab STMR II, and the Vallon VMV16.

  4. The method for staining of anterior lens capsule in cases with small and rigid pupils

    Directory of Open Access Journals (Sweden)

    V. Kumar

    2014-07-01

    Full Text Available Purpose: to evaluate the safety and effectiveness of proposed method for staining with trypan blue anterior lens capsule in cases with small and rigid pupils.Methods: the safety and effectiveness of the proposed method was evaluated in 169 cases having small and rigid pupils of III and IV grade. Surgical steps included: irrigation of anterior chamber with small amount of air, enough to block the pupil; irrigation of posterior chamber with little amount of dye followed by aspiration of air bubble. the excess dye came out and stained the capsule in pupillary area.Results: No difficulty was encountered in irrigating the posterior chamber with dye. Uneven staining of the capsule was noticed in 16 cases (9.5%. In 3 cases (1.8% extensive staining of iris and posterior capsule was observed. Continuous curvilinear capsulorhexis was performed successfully in 97.6% cases. In 4 cases there was radial run of the rhexis extending up to posterior capsule. Postopera- tive inflammation of 1st and 2nd degree was observed in 5.9 and 23.1% cases, which was related to unavoidable trauma to iris tissue during pupil stretching.Conclusion: the proposed method of capsule staining in cases with small and rigid pupils is safe and effective.

  5. The method for staining of anterior lens capsule in cases with small and rigid pupils

    Directory of Open Access Journals (Sweden)

    V. Kumar

    2012-01-01

    Full Text Available Purpose: to evaluate the safety and effectiveness of proposed method for staining with trypan blue anterior lens capsule in cases with small and rigid pupils.Methods: the safety and effectiveness of the proposed method was evaluated in 169 cases having small and rigid pupils of III and IV grade. Surgical steps included: irrigation of anterior chamber with small amount of air, enough to block the pupil; irrigation of posterior chamber with little amount of dye followed by aspiration of air bubble. the excess dye came out and stained the capsule in pupillary area.Results: No difficulty was encountered in irrigating the posterior chamber with dye. Uneven staining of the capsule was noticed in 16 cases (9.5%. In 3 cases (1.8% extensive staining of iris and posterior capsule was observed. Continuous curvilinear capsulorhexis was performed successfully in 97.6% cases. In 4 cases there was radial run of the rhexis extending up to posterior capsule. Postopera- tive inflammation of 1st and 2nd degree was observed in 5.9 and 23.1% cases, which was related to unavoidable trauma to iris tissue during pupil stretching.Conclusion: the proposed method of capsule staining in cases with small and rigid pupils is safe and effective.

  6. Motion-Adaptive Depth Superresolution.

    Science.gov (United States)

    Kamilov, Ulugbek S; Boufounos, Petros T

    2017-04-01

    Multi-modal sensing is increasingly becoming important in a number of applications, providing new capabilities and processing challenges. In this paper, we explore the benefit of combining a low-resolution depth sensor with a high-resolution optical video sensor, in order to provide a high-resolution depth map of the scene. We propose a new formulation that is able to incorporate temporal information and exploit the motion of objects in the video to significantly improve the results over existing methods. In particular, our approach exploits the space-time redundancy in the depth and intensity using motion-adaptive low-rank regularization. We provide experiments to validate our approach and confirm that the quality of the estimated high-resolution depth is improved substantially. Our approach can be a first component in systems using vision techniques that rely on high-resolution depth information.

  7. Analysis of dose perturbation factors of a NACP-02 ionization chamber in clinical electron beams.

    Science.gov (United States)

    Chin, E; Palmans, H; Shipley, D; Bailey, M; Verhaegen, F

    2009-01-21

    For well-guarded plane-parallel ionization chambers, international dosimetry protocols recommend a value of unity for electron perturbation factors in water. However, recent data published by various groups have challenged this. Specifically for the NACP-02 chamber, non-unity electron perturbation factors have already been published by Verhaegen et al (2006 Phys. Med. Biol. 51 1221-35) and Buckley and Rogers (2006 Med. Phys. 33 1788-96). Recently it was found that the mass thickness of the front chamber window can be 35% greater than is listed in the IAEA's TRS-398 absorbed dose protocol (Chin et al 2008 Phys. Med. Biol. 53 N119-26). This study therefore recalculated NACP-02 electron perturbation correction factors for energies 4-18 MeV at depths z(ref) and R(50) to determine the effect of the chamber model change. Results showed that perturbation factors at z(ref) are fairly stable for similar chamber models but become highly sensitive to small changes at deeper depths. The results also showed some dependence on using 1 keV versus 10 keV for the transport cut-off. Additional investigations revealed that the wall perturbation factor, p(wall), is strongly influenced by the chamber back wall at z(ref) and at larger depths small changes in the positioning of the effective point of measurement cause large fluctuations in the final value. Finally, the cavity perturbation factor, p(cav), was found to be primarily influenced by electron backscatter.

  8. 采用眼前段光学相干断层扫描仪检测的健康人眼前段结构相关参数间的关系%Relationship among related parameters of healthy human eye anterior segment structure detected by anterior segment optical coherence tomography

    Institute of Scientific and Technical Information of China (English)

    曾阳发; 刘杏; 王涛; 钟毅敏; 李媚; 何明光

    2009-01-01

    Objective To analyze the relationship among parameters of healthy human eye anterior segment structure detected by anterior segment optical coherence tomography (AS-OCT), and to explore the effect of age on these parameters. Methods AS-OCT was performed in 211 healthy people (211 eyes) to measure the parameters of anterior segment structure, including anterior chamber depth (ACD), anterior chamber horizontal diameter (ACHD), anatomy anterior chamber depth (AACD), lens thickness (LT), ciliary band length (CBL) , lens position (LP) and iris thickness (IT). These parameters were compared between men and women. Relationship among the parameters was analyzed, and effect of age on anterior segment structure biometric values was evaluated. Results The values of ACD, ACHD, AACD, CBL, IT and LP were significantly higher in male than those in female[ACD: (2.87±0.38) mm vs (2.66±0.40) mm; ACHD: (11.73±0.43) mm vs (11.53±0.36) mm;AACD: (3.09±0.19) mm vs (3.00±0.19) mm;CBL: (0.20± 0.09) mm vs (0.17±0.09) mm;iT: (0.36±0.08) mm vs (0.34±0.08) mm; LP: (5.11±0.26) mm vs (4.91± 0.28) ram; all P0.05). ACHD was negatively correlated with age (r=-0.148, P=0.032). LT was positively correlated with age (r=0.646, P=0.000). LT was negatively correlated with ACD (r=-0.714, P=0.000). LT had no significant effect on LP using regression analysis. Conclusions The anterior segments biometric structure of female is narrower than that of male. With aging, the narrowing of ACD is resulted from LT increment. And LP of healthy eyes does not change with aging and LT increment.%目的 采用眼前段光学相干断层扫描仪(AS-OCT)测量健康人的眼前段各参数,并分析参数间的关系以及年龄对其的影响.方法 采用AS-OCT扫描211例健康人(211只眼)眼前段结构,并测量前房深度(ACD)、前房横径(ACHD)、解剖前房深度(AACD)、晶状体厚度(LT)、睫状体带长度(CBL)、晶状体位置(LP)和虹膜厚度(IT).对各参数进行性别间的比较,

  9. Analyses of superficial and depth doses in intraoral radiology

    Energy Technology Data Exchange (ETDEWEB)

    Silva Santos de Oliveira, C.; Morais, R.P. de; Nascimento Souza, D. do [Universidade Federal de Sergipe - CCET - Dept. de Fisica, Sao Cristovao, SE (Brazil)

    2006-07-01

    In this work dosimetric analysis using thermoluminescence technique to study the beams characteristics of x-rays employed in dental radiology has been carried out. The obtained results with CaSO{sub 4}:Dy thermoluminescent dosimeters (TLD) were compared to the doses obtained with parallel-plates ionization chamber. Dosimetric evaluations were also done using radiographic films of large dimensions. The x-rays equipments analyzed were installed in the radiological services of Odontology Department of Sergipe Federal University (U.F.S.). Depending on the anatomical region to be examined the proper exposure time was select, for a fix voltage of 70 kV. The results with TLD and ionization chamber have been determined to female and male individuals. The intraoral regions analysed were the peri apical of the incisors, molar and pre-molar teeth and the occlusive region. These regions were simulated using acrylic plates absorbers installed on the film packet holder. The evaluation of the depth doses in the intraoral tissue was obtained using different acrylic plate thickness. The air kerma values have been evaluated with the ionization chamber located in the dental cone exit of the x-rays equipments. The integrated areas of the thermoluminescent glow curves showed coherent values when compared to the ones obtained with the ionization chamber and both methods presented a linear dependence with the exposition time. The analyses with films have allowed the evaluation of the beam scattering in the simulator apparatus. The studies had proven that the analysis of superficial dose and in depth used in dental radiology can be carried with thermoluminescent dosimeters. (authors)

  10. Estimation and relevance of depth correction in paediatric renal studies

    Energy Technology Data Exchange (ETDEWEB)

    Lythgoe, M.F.; Gradwell, M.J.; Evans, K.; Gordon, I. [Department of Radiology, Great Ormond Street Hospital for Children NHS Trust, London (United Kingdom)

    1998-02-01

    Measurement of absolute renal function by gamma camera techniques requires knowledge of kidney depth to correct for soft tissue attenuation, there is debate about the need to take depth into account when only relative renal function is estimated. The aim of this study was to derive a formula for renal depth in children and to assess the importance of depth correction when relative renal function is assessed with dimercaptosuccinic acid (DMSA) on the gamma camera. In this study, kidney depths were derived from measurements on abdominal computerised tomography (CT) images in 57 children in the supine position with two normally located kidneys. Using best-subset regression analysis, one formula for both left and right kidney depth (KD, cm) was developed based on the easily measured parameters of height (H, cm) and body weight (W, kg). The inclusion of extra variables was found to significantly improve the model compared with a model using weight alone (P<0.005). A second group of 19 children who underwent technetium-99m DMSA scans, had differential function estimated from both anterior and posterior views and the geometric mean method. The mean difference in differential renal function calculated by the geometric mean method versus the posterior image was only 1.2%. In conclusion, we present a new formula for the estimation of paediatric kidney depth for the absolute quantitation of kidney uptake. Further, for normally located kidneys it appears unnecessary to use the geometric mean method or to correct for individual renal depth when calculating differential function. (orig.) With 2 figs., 1 tab., 22 refs.

  11. Influence of the radioactive source position inside the well-type ionization chamber

    Energy Technology Data Exchange (ETDEWEB)

    Kuahara, L.T.; Correa, E.L.; Potiens, M.P.A., E-mail: liliankuahara@usp.br [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The activimeter, instrument used in radionuclide activity measurement, consists primarily of a well type ionization chamber coupled to a special electronic device. Its response, after calibration, is shown in activity units (Becquerel or Curie). The goal of this study is to verify radioactive source position influence over activity measured by this instrument. Radioactive sources measurements were made at different depths inside the ionization chamber well. Results showed maximum variation of -23 %, -28 % and -15 % for {sup 57}Co, {sup 133}Ba and {sup 137}Cs, respectively. (author)

  12. Depth evaluation of intended vs actual intacs intrastromal ring segments using optical coherence tomography.

    Science.gov (United States)

    Barbara, R; Barbara, A; Naftali, M

    2016-01-01

    PurposeEvaluation of actual vs intended intrastromal corneal ring segments (ICRS) implantation depth as measured by anterior segment optical coherence tomography (OCT)MethodsProspective study evaluating 30 Intacs segments implanted manually in 19 eyes of 15 patients suffering from keratoconus. Segment depth evaluation was performed using anterior segment OCT. Measurements were performed above and below the segment at 3 points in relation to the incision site. Statistical analysis was performed using the SAS software for ANOVA, matched t-test, and GLIMMIX procedure.ResultsIntacs segment depth was 153-μm shallower than intended (58% vs 80%). Segment layout demonstrated the proximal and distal portions to be 13-μm shallower and 12-μm deeper (on average), respectively. Intacs segment thickness does not influence implantation depth. Intacs segments implanted in the same eye do not share similar implantation depths. Stromal compression is likely to occur.ConclusionIntacs are implanted at a shallower depth than intended. The 'pocketing' stage prior to implantation most likely has a stronger effect on the segment's final implantation depth than does the incisions' depth.

  13. Monitored Drift Chambers in the ATLAS Detector

    CERN Multimedia

    Herten, G

    Monitored Drift Chambers (MDT) are used in the ATLAS Detector to measure the momentum of high energy muons. They consist of drift tubes, which are filled with an Ar-CO2 gas mixture at 3 bar gas pressure. About 1200 drift chambers are required for ATLAS. They are up to 6 m long. Nevertheless the position of every wire needs to be known with a precision of 20 µm within a chamber. In addition, optical alignment sensors are required to measure the relative position of adjacent chambers with a precision of 30µm. This gigantic task seems impossible at first instance. Indeed it took many years of R&D to invent the right tools and methods before the first chamber could be built according to specifications. Today, at the time when 50% of the chambers have been produced, we are confident that the goal for ATLAS can be reached. The mechanical precision of the chambers could be verified with the x-ray tomograph at CERN. This ingenious device, developed for the MDT system, is able to measure the wire position insid...

  14. On evaluation of depth accuracy in consumer depth sensors

    Science.gov (United States)

    Abd Aziz, Azim Zaliha; Wei, Hong; Ferryman, James

    2015-12-01

    This paper presents an experimental study of different depth sensors. The aim is to answer the question, whether these sensors give accurate data for general depth image analysis. The study examines the depth accuracy between three popularly used depth sensors; ASUS Xtion Prolive, Kinect Xbox 360 and Kinect for Windows v2. The main attention is to study on the stability of pixels in the depth image captured at several different sensor-object distances by measuring the depth returned by the sensors within specified time intervals. The experimental results show that the fluctuation (mm) of the random selected pixels within the target area, increases with increasing distance to the sensor, especially on the Kinect for Xbox 360 and the Asus Xtion Prolive. Both of these sensors provide pixels fluctuation between 20mm and 30mm at a sensor-object distance beyond 1500mm. However, the pixel's stability of the Kinect for Windows v2 not affected much with the distance between the sensor and the object. The maximum fluctuation for all the selected pixels of Kinect for Windows v2 is approximately 5mm at sensor-object distance of between 800mm and 3000mm. Therefore, in the optimal distance, the best stability achieved.

  15. Making MUSIC: A multiple sampling ionization chamber

    Energy Technology Data Exchange (ETDEWEB)

    Shumard, B. [Argonne National Laboratory, Building 203 H-113, Argonne, IL 60439 (United States)]. E-mail: shumard@phy.anl.gov; Henderson, D.J. [Argonne National Laboratory, Building 203 H-113, Argonne, IL 60439 (United States); Rehm, K.E. [Argonne National Laboratory, Building 203 H-113, Argonne, IL 60439 (United States); Tang, X.D. [Argonne National Laboratory, Building 203 H-113, Argonne, IL 60439 (United States)

    2007-08-15

    A multiple sampling ionization chamber (MUSIC) was developed for use in conjunction with the Atlas scattering chamber (ATSCAT). This chamber was developed to study the ({alpha}, p) reaction in stable and radioactive beams. The gas filled ionization chamber is used as a target and detector for both particles in the outgoing channel (p + beam particles for elastic scattering or p + residual nucleus for ({alpha}, p) reactions). The MUSIC detector is followed by a Si array to provide a trigger for anode events. The anode events are gated by a gating grid so that only ({alpha}, p) reactions where the proton reaches the Si detector result in an anode event. The MUSIC detector is a segmented ionization chamber. The active length of the chamber is 11.95 in. and is divided into 16 equal anode segments (3.5 in. x 0.70 in. with 0.3 in. spacing between pads). The dead area of the chamber was reduced by the addition of a Delrin snout that extends 0.875 in. into the chamber from the front face, to which a mylar window is affixed. 0.5 in. above the anode is a Frisch grid that is held at ground potential. 0.5 in. above the Frisch grid is a gating grid. The gating grid functions as a drift electron barrier, effectively halting the gathering of signals. Setting two sets of alternating wires at differing potentials creates a lateral electric field which traps the drift electrons, stopping the collection of anode signals. The chamber also has a reinforced mylar exit window separating the Si array from the target gas. This allows protons from the ({alpha}, p) reaction to be detected. The detection of these protons opens the gating grid to allow the drift electrons released from the ionizing gas during the ({alpha}, p) reaction to reach the anode segment below the reaction.

  16. 30 CFR 77.305 - Access to drying chambers, hot gas inlet chambers and ductwork; installation and maintenance.

    Science.gov (United States)

    2010-07-01

    ... chambers and ductwork; installation and maintenance. 77.305 Section 77.305 Mineral Resources MINE SAFETY... drying chambers, hot gas inlet chambers and ductwork; installation and maintenance. Drying chambers, hot gas inlet chambers and all ductwork in which coal dust may accumulate shall be equipped with...

  17. Radiation-induced foil electret chamber

    Science.gov (United States)

    Fallone, B. G.; Podgorsak, E. B.

    1983-10-01

    Saturation current densities, extrapolated electric fields, and electret-charging and -discharging current-density profiles in an ionization electret chamber are discussed as a function of various chamber parameters, such as air-gap and polymer thickness, polarizing electrode material, exposure rate, etc. Both the saturation current density and the extrapolated electric field consist of two components; one is linear with the air-gap thickness and is attributed to primary ionization in air, and the other exhibits exponential saturation and is attributed to air ionization caused by photoelectrons backscattered into the chamber sensitive volume from the polarizing electrode.

  18. LEP vacuum chamber, cross-section

    CERN Multimedia

    1983-01-01

    Cross-section of the final prototype for the LEP vacuum chamber. The elliptic main-opening is for the beam. The small channel to the left is for the cooling water, to carry away the heat deposited by the synchrotron radiation. The square channel to the right houses the Non-Evaporable Getter (NEG) pump. The chamber is made from extruded aluminium. Its outside is clad with lead, to stop the synchrotron radiation emitted by the beam. For good adherence between Pb and Al, the Al chamber was coated with a thin layer of Ni. Ni being slightly magnetic, some resulting problems had to be overcome. See also 8301153.

  19. Bubble chamber: Omega production and decay

    CERN Multimedia

    1973-01-01

    This image is of real particle tracks taken from the CERN 2 m liquid hydrogen bubble chamber and shows the production and decay of a negative omega particle. A negative kaon enters the chamber which decays into many particles, including a negative omega that travels a short distance before decaying into more particles. 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.

  20. Sample chambers with mother-daughter mode

    Energy Technology Data Exchange (ETDEWEB)

    Wilk, P.A.; Gregorich, K.E.; Hoffman, D.C.

    2001-07-12

    A set of eight stand-alone sample chambers with a common interface were constructed at LBNL for improved detection of alpha and fission decay chains over currently used designs. The stainless steel chambers (see Figure 1 for a schematic and Figure 2 for a photograph of a completed chamber) were constructed to allow for low background detection of a daughter event by removal of the sample following the detection of a parent event. This mother-daughter mode of operation has been utilized successfully with our Merry-go-Round (MG) detection system [Gregorich 1994].

  1. Mini-open anterior lumbar interbody fusion.

    Science.gov (United States)

    Gandhoke, Gurpreet S; Ricks, Christian; Tempel, Zachary; Zuckerbraun, Brian; Hamilton, D Kojo; Okonkwo, David O; Kanter, Adam S

    2016-07-01

    In deformity surgery, anterior lumbar interbody fusion provides excellent biomechanical support, creates a broad surface area for arthrodesis, and induces lordosis in the lower lumbar spine. Preoperative MRI, plain radiographs, and, when available, CT scan should be carefully assessed for sacral slope as it relates to pubic symphysis, position of the great vessels (especially at L4/5), disc space height, or contraindication to an anterior approach. This video demonstrates the steps in an anterior surgical procedure with minimal open exposure. The video can be found here: https://youtu.be/r3bC4_vu1hQ .

  2. How I do it: Anterior pull-through tympanoplasty for anterior eardrum perforations.

    Science.gov (United States)

    Harris, Jeffrey P; Wong, Yu-Tung; Yang, Tzong-Hann; Miller, Mia

    2016-01-01

    Conclusions This technique is offered as a convenient and reliable method for cases with anterior TM perforation and inadequate anterior remnant. Objectives Chronic otitis media surgery is one of the most common procedures in otology. Anterior tympanic membrane (TM) perforation with inadequate anterior remnant is associated with higher rates of graft failure. It was the goal of this series to evaluate the anatomical and functional outcomes of a modified underlay myringoplasty technique-the anterior pull-through method. Materials and methods In a retrospective clinical study, 13 patients with anterior TM perforations with inadequate anterior remnants underwent tympanoplasty with anterior pull-through technique. The anterior tip of the temporalis fascia was pulled through and secured in a short incision lateral to the anterior part of the annulus. Data on graft take rate, pre-operative, and post-operative hearing status were analyzed. Results A graft success rate of 84.6% (11 out of 13) was achieved, without lateralization, blunting, atelectasia, or epithelial pearls. The air-bone gap was 21.5 ± 6.8 dB before intervention and 11.75 ± 5.7 dB after surgery (p = 0.003).

  3. Quadriceps muscle contraction protects the anterior cruciate ligament during anterior tibial translation.

    Science.gov (United States)

    Aune, A K; Cawley, P W; Ekeland, A

    1997-01-01

    The proposed skiing injury mechanism that suggests a quadriceps muscle contraction can contribute to anterior cruciate ligament rupture was biomechanically investigated. The effect of quadriceps muscle force on a knee specimen loaded to anterior cruciate ligament failure during anterior tibial translation was studied in a human cadaveric model. In both knees from six donors, average age 41 years (range, 31 to 65), the joint capsule and ligaments, except the anterior cruciate ligament, were cut. The quadriceps tendon, patella, patellar tendon, and menisci were left intact. One knee from each pair was randomly selected to undergo destructive testing of the anterior cruciate ligament by anterior tibial translation at a displacement rate of 30 mm/sec with a simultaneously applied 889 N quadriceps muscle force. The knee flexion during testing was 30 degrees. As a control, the contralateral knee was loaded correspondingly, but only 5 N of quadriceps muscle force was applied. The ultimate load for the knee to anterior cruciate ligament failure when tested with 889 N quadriceps muscle force was 22% +/- 18% higher than that of knees tested with 5 N of force. The linear stiffness increased by 43% +/- 30%. These results did not support the speculation that a quadriceps muscle contraction contributes to anterior cruciate ligament failure. In this model, the quadriceps muscle force protected the anterior cruciate ligament from injury during anterior tibial translation.

  4. [Iritis with destabilization of the intraocular pressure due to dislocation of a posterior chamber intraocular lens].

    Science.gov (United States)

    Handzel, D M

    2012-04-01

    This report concerns the case of a 67-year-old male patient who underwent uncomplicated phacoemulsification with implantation of a posterior chamber intraocular lens (IOL). After an interval of 2 months the patient developed iritis together with an uncontrollable increase in intraocular pressure. After a detailed examination a dislocated haptic of the IOL was identified as the cause of the symptoms. The dislocation had led to uveitis-glaucoma-hyphema syndrome although no hemorrhage was observed. In addition to this complication the haptic had arroded the zonular complex which made implantation of an anterior chamber lens necessary. Although improvements in operating techniques, lens materials and designs have been made uveitis-glaucoma-hyphema syndrome has to be kept in mind. Surgical intervention is the only therapeutic option.

  5. Archetypal Depth Criticism and Melville.

    Science.gov (United States)

    Maud, Ralph

    1983-01-01

    Applies psychologist James Hillman's idea of soul-making to literary studies. Uses the works of Melville to discuss the terms (1) depth, (2) image, and (3) archetype as they relate to the concept of soul-making. (MM)

  6. Formation depths of Fraunhofer lines

    CERN Document Server

    Gurtovenko, E A

    2015-01-01

    We have summed up our investigations performed in 1970--1993. The main task of this paper is clearly to show processes of formation of spectral lines as well as their distinction by validity and by location. For 503 photospheric lines of various chemical elements in the wavelength range 300--1000 nm we list in Table the average formation depths of the line depression and the line emission for the line centre and on the half-width of the line, the average formation depths of the continuum emission as well as the effective widths of the layer of the line depression formation. Dependence of average depths of line depression formation on excitation potential, equivalent widths, and central line depth are demonstrated by iron lines.

  7. Potential errors in relative dose measurements in kilovoltage photon beams due to polarity effects in plane-parallel ionisation chambers

    Science.gov (United States)

    Dowdell, S.; Tyler, M.; McNamara, J.; Sloan, K.; Ceylan, A.; Rinks, A.

    2016-12-01

    Plane-parallel ionisation chambers are regularly used to conduct relative dosimetry measurements for therapeutic kilovoltage beams during commissioning and routine quality assurance. This paper presents the first quantification of the polarity effect in kilovoltage photon beams for two types of commercially available plane-parallel ionisation chambers used for such measurements. Measurements were performed at various depths along the central axis in a solid water phantom and for different field sizes at 2 cm depth to determine the polarity effect for PTW Advanced Markus and Roos ionisation chambers (PTW-Freiburg, Germany). Data was acquired for kilovoltage beams between 100 kVp (half-value layer (HVL)  =  2.88 mm Al) and 250 kVp (HVL  =  2.12 mm Cu) and field sizes of 3-15 cm diameter for 30 cm focus-source distance (FSD) and 4  ×  4 cm2-20  ×  20 cm2 for 50 cm FSD. Substantial polarity effects, up to 9.6%, were observed for the Advanced Markus chamber compared to a maximum 0.5% for the Roos chamber. The magnitude of the polarity effect was observed to increase with field size and beam energy but was consistent with depth. The polarity effect is directly influenced by chamber design, with potentially large polarity effects for some plane-parallel ionisation chambers. Depending on the specific chamber used, polarity corrections may be required for output factor measurements of kilovoltage photon beams. Failure to account for polarity effects could lead to an incorrect dose being delivered to the patient.

  8. Potential errors in relative dose measurements in kilovoltage photon beams due to polarity effects in plane-parallel ionisation chambers.

    Science.gov (United States)

    Dowdell, S; Tyler, M; McNamara, J; Sloan, K; Ceylan, A; Rinks, A

    2016-11-15

    Plane-parallel ionisation chambers are regularly used to conduct relative dosimetry measurements for therapeutic kilovoltage beams during commissioning and routine quality assurance. This paper presents the first quantification of the polarity effect in kilovoltage photon beams for two types of commercially available plane-parallel ionisation chambers used for such measurements. Measurements were performed at various depths along the central axis in a solid water phantom and for different field sizes at 2 cm depth to determine the polarity effect for PTW Advanced Markus and Roos ionisation chambers (PTW-Freiburg, Germany). Data was acquired for kilovoltage beams between 100 kVp (half-value layer (HVL)  =  2.88 mm Al) and 250 kVp (HVL  =  2.12 mm Cu) and field sizes of 3-15 cm diameter for 30 cm focus-source distance (FSD) and 4  ×  4 cm(2)-20  ×  20 cm(2) for 50 cm FSD. Substantial polarity effects, up to 9.6%, were observed for the Advanced Markus chamber compared to a maximum 0.5% for the Roos chamber. The magnitude of the polarity effect was observed to increase with field size and beam energy but was consistent with depth. The polarity effect is directly influenced by chamber design, with potentially large polarity effects for some plane-parallel ionisation chambers. Depending on the specific chamber used, polarity corrections may be required for output factor measurements of kilovoltage photon beams. Failure to account for polarity effects could lead to an incorrect dose being delivered to the patient.

  9. Characterization of rat model of acute anterior uveitis using optical coherence tomography angiography

    Science.gov (United States)

    Choi, Woo June; Pepple, Kathryn L.; Zhi, Zhongwei; Wang, Ruikang K.

    2015-03-01

    Uveitis, or ocular inflammation, is a cause of severe visual impairment. Rodent models of uveitis are powerful tools used to investigate the pathological mechanisms of ocular inflammation and to study the efficacy of new therapies prior to human testing. In this paper, we report the utility of spectral-domain optical coherence tomography (SD-OCT) angiography in characterizing the inflammatory changes induced in the anterior segment of a rat model of uveitis. Acute anterior uveitis (AAU) was induced in two rats by intravitreal injection of a killed mycobacterial extract. One of them received a concurrent periocular injection of steroids to model a treatment effect. OCT imaging was performed prior to inflammation induction on day 0 (baseline), and 2 days post-injection (peak inflammation). Baseline and inflamed images were compared. OCT angiography identified swelling of the cornea, inflammatory cells in the anterior and posterior chambers, a fibrinous papillary membrane, and dilation of iris vessels in the inflamed eyes when compared to baseline images. Steroid treatment was shown to prevent the changes associated with inflammation. This is a novel application of anterior OCT imaging in animal models of uveitis, and provides a high resolution, in vivo assay for detecting and quantifying ocular inflammation and the response to new therapies.

  10. Results of cataract surgery and plasma ablation posterior capsulotomy in anterior persistent hyperplastic primary vitreous

    Directory of Open Access Journals (Sweden)

    Rajesh Sinha

    2013-01-01

    Full Text Available Purpose: To report the feasibility and outcome of lens aspiration, and Fugo blade-assisted capsulotomy and anterior vitrectomy in eyes with anterior persistent hyperplastic primary vitreous (PHPV. Materials and Methods: In this case series, 10 eyes of 10 patients with anterior PHPV underwent lens aspiration. The vascularized posterior capsule was cut with a Fugo blade (plasma knife and removed with a vitrector. A foldable posterior chamber intraocular lens (IOL was implanted in eight eyes and the outcomes were evaluated. Results: The mean age of patients was 16.8 ± 6.37 months (range: 5 to 28 months. The surgery was completed successfully in all eyes. There were no cases of intraocular hemorrhage intraoperatively. Foldable acrylic IOL was implanted in the bag in 3 eyes and in the sulcus in 5 eyes. Two eyes were microphthalmic and did no undergo IOL implantation (aphakic. None of the eyes had a significant reaction or elevated intraocular pressure postoperatively. The follow-up ranged from 4 to 21 months. All the pseudophakic eyes achieved a best corrected visual acuity of ≥20/200 with 50% (4/8 of these eyes with ≥20/60 vision. Conclusion: Lens aspiration followed by posterior capsulotomy with Fugo blade-assisted plasma ablation is a feasible technique for performing successful lens surgery in cases with florid anterior PHPV.

  11. Magma Chambers, Thermal Energy, and the Unsuccessful Search for a Magma Chamber Thermostat

    Science.gov (United States)

    Glazner, A. F.

    2015-12-01

    Although the traditional concept that plutons are the frozen corpses of huge, highly liquid magma chambers ("big red blobs") is losing favor, the related notion that magma bodies can spend long periods of time (~106years) in a mushy, highly crystalline state is widely accepted. However, analysis of the thermal balance of magmatic systems indicates that it is difficult to maintain a significant portion in a simmering, mushy state, whether or not the system is eutectic-like. Magma bodies cool primarily by loss of heat to the Earth's surface. The balance between cooling via energy loss to the surface and heating via magma accretion can be denoted as M = ρLa/q, where ρ is magma density, L is latent heat of crystallization, a is the vertical rate of magma accretion, and q is surface heat flux. If M>1, then magma accretion outpaces cooling and a magma chamber forms. For reasonable values of ρ, L, and q, the rate of accretion amust be > ~15 mm/yr to form a persistent volume above the solidus. This rate is extremely high, an order of magnitude faster than estimated pluton-filling rates, and would produce a body 10 km thick in 700 ka, an order of magnitude faster than geochronology indicates. Regardless of the rate of magma supply, the proportion of crystals in the system must vary dramatically with depth at any given time owing to transfer of heat. Mechanical stirring (e.g., by convection) could serve to homogenize crystal content in a magma body, but this is unachievable in crystal-rich, locked-up magma. Without convection the lower part of the magma body becomes much hotter than the top—a process familiar to anyone who has scorched a pot of oatmeal. Thermal models that succeed in producing persistent, large bodies of magma rely on scenarios that are unrealistic (e.g., omitting heat loss to the planet's surface), self-fulfilling prophecies (e.g., setting unnaturally high temperatures as fixed boundary conditions), or physically unreasonable (e.g., magma is intruded

  12. RADAR Anechoic Chamber/RCS Measurements Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The RF Anechoic Chamber is 56 feet long by 12 feet high by 13.5 feet wide, with an adjoining electronic computer control room. A double door entrance at one end of...

  13. Liquid ionization chambers for LET determination

    DEFF Research Database (Denmark)

    Kaiser, Franz-Joachim; Bassler, Niels; Tölli, Heikki

    Liquid ionization chambers [1] (LICs) have have been used in the last decades as background dosemeters. Since a few years LICs are also commercially available for dosimetry and are used for measurements of dose distributions where a high spatial distribution is necessary. Also in the last decades...... a differential equation applying several simplifications and approximations leading to discrepancies between theory and experiments [3]. The theory predicts the collection efficiency as a function of the electrical field and was applied for both air filled ionization chambers and liquid filled ionization...... chambers. For liquids the LET can be roughly deduced from the collection efficiency dependency on the electrical field inside a liquid ionization chambers [4] using an extrapolation method. We solved the fundamental differential equation again presented by Jaffe numerically, but now taking into account...

  14. Developing cloud chambers with high school students

    CERN Document Server

    Ishizuka, Ryo; Sato, Shoma; Zeze, Syoji

    2013-01-01

    The result and outcome of the cloud chamber project, which aims to develop a cloud chamber useful for science education is reported in detail. A project includes both three high school students and a teacher as a part of Super Science High School (SSH) program in our school. We develop a dry ice free cloud chamber using salt and ice (or snow). Technical detail of the chamber is presented. We also argue how the project affects student's cognition, motivation, academic skills and behavior. The research project had been done in very similar way to those of professional researchers, i.e., planning research, applying fund, writing a paper and giving a talk in conferences. From interviews with students, we learn that such style of scientific activity is very effective in promoting student's motivation for learning science.

  15. MAN-IN-SIMULANT TEST (MIST) CHAMBER

    Data.gov (United States)

    Federal Laboratory Consortium — The MIST chamber uses methyl salicylate (oil of wintergreen) vapor as a simulant for HD agent to conduct system level evaluations of chemical protective ensembles....

  16. High Performance Methane Thrust Chamber (HPMTC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop a High-Performance Methane Thrust Chamber (HPMRE) to meet the demands of advanced chemical propulsion systems for deep-space mission...

  17. Developing Cloud Chambers with High School Students

    Science.gov (United States)

    Ishizuka, Ryo; Tan, Nobuaki; Sato, Shoma; Zeze, Syoji

    The result and outcome of the cloud chamber project, which aims to develop a cloud chamber useful for science education is reported in detail. A project includes both three high school students and a teacher as a part of Super Science High School (SSH) program in our school. We develop a dry-ice-free cloud chamber using salt and ice (or snow). Technical details of the chamber are described. We also argue how the project have affected student's cognition, motivation, academic skills and behavior. The research project has taken steps of professional researchers, i.e., in planning research, applying fund, writing a paper and giving a talk in conferences. From interviews with students, we have learnt that such style of scientific activity is very effective in promoting student's motivation for learning science.

  18. Guideline on anterior cruciate ligament injury

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan); M.T. Poldervaart (Michelle T.); R.L. Diercks (Ron L.); A.W.F.M. Fievez (Alex W.F.M.); T.W. Patt (Thomas W.); C.P. van der Hart (Cor P.); E.R. Hammacher (Eric); F. van der Meer (Fred); E.A. Goedhart (Edwin A.); A.F. Lenssen (Anton F); S.B. Muller-Ploeger (Sabrina B); M.A. Pols (Margreet); D.B.F. Saris (Daniel)

    2012-01-01

    textabstractThe Dutch Orthopaedic Association has a long tradition of development of practical clinical guidelines. Here we present the recommendations from the multidisciplinary clinical guideline working group for anterior cruciate ligament injury. The following 8 clinical questions were formulate

  19. Care of children with anterior uveitis.

    Science.gov (United States)

    Kanski, J J

    1981-09-01

    The clinical features of 290 children with anterior uveitis are presented. The vast majority suffered from chronic uveitis. Specific uveitis entities in children include the syndrome of 'chronic iridocyclitis' in girls, heterochromic cyclitis, and pars planitis. Systemic associations include sarcoidosis, the Vogt-Harada-Koyanagi syndrome, and the seronegative arthritides (juvenile chronic arthritis, juvenile ankylosing spondylitis, psoriatic arthritis, and rarely Reiter's and Beçet's syndromes). Children with a pauciarticular onset of juvenile chronic arthritis, especially when combined with positive findings for antinuclear antibody, are at particular risk of developing chronic anterior uveitis. Most cases of chronic anterior uveitis can be controlled with topical corticosteroids. Those that are resistant to both topical and systemic corticosteroids may have to be treated with chlorambucil. The operation of lensectomy is a great advance in the management of complicated cataract. Secondary glaucoma is the most devastating complication of chronic anterior uveitis in children and responds poorly to therapy.

  20. Head positioning for anterior circulation aneurysms microsurgery

    Directory of Open Access Journals (Sweden)

    Feres Chaddad-Neto

    2014-11-01

    Full Text Available Objective To study the ideal patient's head positioning for the anterior circulation aneurysms microsurgery. Method We divided the study in two parts. Firstly, 10 fresh cadaveric heads were positioned and dissected in order to ideally expose the anterior circulation aneurysm sites. Afterwards, 110 patients were submitted to anterior circulation aneurysms microsurgery. During the surgery, the patient's head was positioned accordingly to the aneurysm location and the results from the cadaveric study. The effectiveness of the position was noted. Results We could determine mainly two patterns for head positioning for the anterior circulation aneurysms. Conclusion The best surgical exposure is related to specific head positions. The proper angle of microscopic view may minimize neurovascular injury and brain retraction.

  1. Electrostatic fields in an ionization chamber electret

    Science.gov (United States)

    Fallone, B. G.; Podgorsak, E. B.

    1983-09-01

    The theory of linear systems is used to derive the potential and electric field in distance space in a cylindrical polarization/depolarization electret chamber. General solutions for the near, intermediate, and far regions are given and their domains of convergence discussed. On the axis of the chamber the solutions for the electret surface are equal to those obtained from Gauss's and Kirchoff's laws, and at large distances from the surface to those obtained from the introduction of a dipole layer model.

  2. The drift chambers of the NOMAD experiment

    Energy Technology Data Exchange (ETDEWEB)

    Anfreville, M.; Astier, P.; Authier, M.; Baldisseri, A.; Banner, M.; Besson, N.; Bouchez, J.; Castera, A.; Cloue, O.; Dumarchez, J. E-mail: jacques.dumarchez@cern.ch; Dumps, L.; Gangler, E.; Gosset, J.; Hagner, C.; Jollec, C.; Lachaud, C.; Letessier-Selvon, A.; Levy, J.-M.; Linssen, L.; Meyer, J.-P.; Ouriet, J.-P.; Passerieux, J.-P.; Margaley, T.P.T. Pedrol; Placci, A.; Pluquet, A.; Poinsignon, J.; Popov, B.A.; Rathouit, P.; Schahmaneche, K.; Stolarczyk, T.; Uros, V.; Vannucci, F.; Vo, M.K.; Zaccone, H

    2002-04-01

    We present a detailed description of the drift chambers used as an active target and a tracking device in the NOMAD experiment at CERN. The main characteristics of these chambers are a large area (3{center_dot}3 m{sup 2}), a self-supporting structure made of light composite materials and a low cost. A spatial resolution of 150 {mu}m has been achieved with a single hit efficiency of 97%.

  3. The Gargamelle heavy liquid bubble chamber

    CERN Multimedia

    1970-01-01

    This image shows the Gargamelle heavy liquid bubble chamber. It was used to detect particles in experiments at the PS between 1970 and 1976 before being moved to the SPS. In 1973, while working on the PS, it detected the first neutral current, an interaction vital to the electroweak theory. In 1978 a large fissure appeared in the body of the chamber and Gargamelle was stopped in 1979.

  4. The world's largest time projection chamber

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    Peter Glassel, the technical coordinator for the ALICE time projection chamber, is seen sitting inside the detector; the largest in the world at nearly 100 cubic metres. Thousands of wires are connected to read out electronic data produced as particles are created in lead-lead collisions at the centre of the detector. These particles will cause the medium within the time projection chamber to ionise along their tracks allowing the particle paths to be recreated.

  5. Tracking with wire chambers at high luminosities

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, G.G. (Indiana Univ., Bloomington, IN (USA) Stanford Linear Accelerator Center, Menlo Park, CA (USA))

    1989-12-01

    Radiation damage and rate limitations impose severe constraints on wire chambers at the SSC. Possible conceptual designs for wire chamber tracking systems that satisfy these constraints are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 11 refs., 10 figs.

  6. Using a ceramic chamber in kicker magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S.

    1993-05-01

    A ceramic chamber inside kicker magnets can provide the relevant field risetime. On the other hand, some metallic coating inside has to prevent static charge buildup and shield the beam from ceramic and ferrite at high frequencies to avoid possible resonances. The issues concerning the metallized ceramic chamber, such as coupling impedances and requirements on the coating, are studied to find a compromise solution for kickers of the Medium Energy Booster at the Superconducting Super Collider.

  7. Upper anterior zone restoration with composites

    OpenAIRE

    Lamas Lara, César; CD, Docente del Área de Operatoria Dental y Endodoncia de la Facultad de Odontología de la UNMSM.; Angulo de la Vega, Giselle; CD, Alumna de la Especialidad de Rehabilitación Oral de la Facultad de Odontología de la UNMSM.

    2014-01-01

    The anterior sector problems are very common in our professional practice and became vital importance to make a suitable rehabilitation in these cases; we can not do a good rehabilitation if we do not know the basic characteristics, both aesthetic and functional. Today the composites are a valid alternative for the restoration of the anterior sector, since they offer to us a conservative and aesthetic possibility, but independently of the material to use we have to based on certain rules or p...

  8. Erlotinib-related bilateral anterior uveitis

    Science.gov (United States)

    Ali, Kashif; Kumar, Indu; Usman-Saeed, Muniba; Usman Saeed, Muhammad

    2011-01-01

    The authors report the case of a 68-year-old woman with secondary adenocarcinoma of the lungs from an unknown primary. Erlotinib was started which produced symptoms suggestive of uveitis. Erlotinib was stopped and restarted a month later at a lower dose, which resulted in severe bilateral anterior uveitis. The uveitis settled after stopping erlotinib and treatment with topical steroids and cycloplegics. To the best of the authors’ knowledge, this is the first case of erlotinib-related anterior uveitis. PMID:22694887

  9. Performance parameters of a liquid filled ionization chamber array

    Energy Technology Data Exchange (ETDEWEB)

    Poppe, B.; Stelljes, T. S.; Looe, H. K.; Chofor, N. [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121, Germany and WG Medical Radiation Physics, Carl von Ossietzky University, Oldenburg 26121 (Germany); Harder, D. [Prof. em., Medical Physics and Biophysics, Georg August University, Göttingen 37073 (Germany); Willborn, K. [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121 (Germany)

    2013-08-15

    Purpose: In this work, the properties of the two-dimensional liquid filled ionization chamber array Octavius 1000SRS (PTW-Freiburg, Germany) for use in clinical photon-beam dosimetry are investigated.Methods: Measurements were carried out at an Elekta Synergy and Siemens Primus accelerator. For measurements of stability, linearity, and saturation effects of the 1000SRS array a Semiflex 31013 ionization chamber (PTW-Freiburg, Germany) was used as a reference. The effective point of measurement was determined by TPR measurements of the array in comparison with a Roos chamber (type 31004, PTW-Freiburg, Germany). The response of the array with varying field size and depth of measurement was evaluated using a Semiflex 31010 ionization chamber as a reference. Output factor measurements were carried out with a Semiflex 31010 ionization chamber, a diode (type 60012, PTW-Freiburg, Germany), and the detector array under investigation. The dose response function for a single detector of the array was determined by measuring 1 cm wide slit-beam dose profiles and comparing them against diode-measured profiles. Theoretical aspects of the low pass properties and of the sampling frequency of the detector array were evaluated. Dose profiles measured with the array and the diode detector were compared, and an intensity modulated radiation therapy (IMRT) field was verified using the Gamma-Index method and the visualization of line dose profiles.Results: The array showed a short and long term stability better than 0.1% and 0.2%, respectively. Fluctuations in linearity were found to be within ±0.2% for the vendor specified dose range. Saturation effects were found to be similar to those reported in other studies for liquid-filled ionization chambers. The detector's relative response varied with field size and depth of measurement, showing a small energy dependence accounting for maximum signal deviations of ±2.6% from the reference condition for the setup used. The σ-values of

  10. In vitro penetration of bleaching agents into the pulp chamber

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Valera, M C; Mancini, M N G

    2004-01-01

    To investigate pulp chamber penetration of bleaching agents in teeth following restorative procedures.......To investigate pulp chamber penetration of bleaching agents in teeth following restorative procedures....

  11. Expandable Purge Chambers Would Protect Cryogenic Fittings

    Science.gov (United States)

    Townsend, Ivan I., III

    2004-01-01

    Expandable ice-prevention and cleanliness-preservation (EIP-CP) chambers have been proposed to prevent the accumulation of ice or airborne particles on quick-disconnect (QD) fittings, or on ducts or tubes that contain cryogenic fluids. In the original application for which the EIP-CP chambers were conceived, there is a requirement to be able to disconnect and reconnect the QD fittings in rapid succession. If ice were to form on the fittings by condensation and freezing of airborne water vapor on the cold fitting surfaces, the ice could interfere with proper mating of the fittings, making it necessary to wait an unacceptably long time for the ice to thaw before attempting reconnection. By keeping water vapor away from the cold fitting surfaces, the EIP-CP chambers would prevent accumulation of ice, preserving the ability to reconnect as soon as required. Basically, the role of an EIP-CP chamber would be to serve as an enclosure for a flow of dry nitrogen gas that would keep ambient air away from QD cryogenic fittings. An EIP-CP chamber would be an inflatable device made of a fabriclike material. The chamber would be attached to an umbilical plate holding a cryogenic QD fitting.

  12. Temperature Studies for ATLAS MDT BOS Chambers

    CERN Document Server

    Engl, A; Hertenberger, R; Mameghani, R; Merkl, D; Rauscher, F; Schaile, A D; Ströhmer, R

    2009-01-01

    Data sets with high statistics taken at the cosmic ray facility, equipped with 3 ATLAS BOS MDT chambers, in Garching (Munich) have been used to study temperature and pressure effects on gas gain and drifttime. The deformation of a thermally expanded chamber was reconstructed using the internal RasNik alignment monitoring system and the tracks from cosmic data. For these studies a heating system was designed to increase the temperature of the middle chamber by up to 20 Kelvins over room temperature. For comparison the temperature effects on gas properties have been simulated with Garfield. The maximum drifttime decreased under temperature raise by -2.21 +- 0.08 ns/K, in agreement with the results of pressure variations and the Garfield simulation. The increased temperatures led to a linear increase of the gas gain of about 2.1% 1/K. The chamber deformation has been analyzed with the help of reconstructed tracks. By the comparison of the tracks through the reference chambers with these through the test chamber ...

  13. The GODDESS ionization chamber: developing robust windows

    Science.gov (United States)

    Blanchard, Rose; Baugher, Travis; Cizewski, Jolie; Pain, Steven; Ratkiewicz, Andrew; Goddess Collaboration

    2015-10-01

    Reaction studies of nuclei far from stability require high-efficiency arrays of detectors and the ability to identify beam-like particles, especially when the beam is a cocktail beam. The Gammasphere ORRUBA Dual Detectors for Experimental Structure Studies (GODDESS) is made up of the Oak Ridge-Rutgers University Barrel Array (ORRUBA) of silicon detectors for charged particles inside of the gamma-ray detector array Gammasphere. A high-rate ionization chamber is being developed to identify beam-like particles. Consisting of twenty-one alternating anode and cathode grids, the ionization chamber sits downstream of the target chamber and is used to measure the energy loss of recoiling ions. A critical component of the system is a thin and robust mylar window which serves to separate the gas-filled ionization chamber from the vacuum of the target chamber with minimal energy loss. After construction, windows were tested to assure that they would not break below the required pressure, causing harm to the wire grids. This presentation will summarize the status of the ionization chamber and the results of the first tests with beams. This work is supported in part by the U.S. Department of Energy and National Science Foundation.

  14. Chamber for Growing and Observing Fungi

    Science.gov (United States)

    Pierson, Duane L.; Molina, Thomas C.

    2005-01-01

    A chamber has been designed to enable growth and observation of microcolonies of fungi in isolation from the external environment. Unlike prior fungus-growing apparatuses, this chamber makes it possible to examine a fungus culture without disrupting it. Partly resembling a small picture frame, the chamber includes a metal plate having a rectangular through-thethickness opening with recesses for a top and a bottom cover glass, an inlet for air, and an inlet for water. The bottom cover glass is put in place and held there by clips, then a block of nutrient medium and a moisture pad are placed in the opening. The block is inoculated, then the top cover glass is put in place and held there by clips. Once growth is evident, the chamber can be sealed with tape. Little (if any) water evaporates past the edges of the cover glasses, and, hence there is little (if any) need to add water. A microscope can be used to observe the culture through either cover glass. Because the culture is sealed in the chamber, it is safe to examine the culture without risking contamination. The chamber can be sterilized and reused.

  15. Shallow magma chamber under the Wudalianchi Volcanic Field unveiled by seismic imaging with dense array

    Science.gov (United States)

    Li, Zhiwei; Ni, Sidao; Zhang, Baolong; Bao, Feng; Zhang, Senqi; Deng, Yang; Yuen, David A.

    2016-05-01

    The Wudalianchi Volcano Field (WDF) is a typical intraplate volcano in northeast China with generation mechanism not yet well understood. As its last eruption was around 300 years ago, the present risk for volcano eruption is of particular public interest. We have carried out a high-resolution ambient noise tomography to investigate the location of magma chambers beneath the volcanic cones with a dense seismic array of 43 seismometers and ~ 6 km spatial interval. Significant low-velocity anomalies up to 10% are found at 7-13 km depth under the Weishan volcano, consistent with the pronounced high electrical-conductivity anomalies from previous magnetotelluric survey. We propose these extremely low velocity anomalies can be interpreted as partial melting in a shallow magma chamber with volume at least 200 km3 which may be responsible for most of the recent volcanic eruptions in WDF. Therefore, this magma chamber may pose a serious hazard for northeast China.

  16. Droplets coalescence at microchannel intersection chambers with different shapes

    Science.gov (United States)

    Liu, Zhaomiao; Wang, Xiang; Cao, Rentuo; Pang, Yan

    2016-11-01

    The influence of microchannel intersection chamber shape on droplets coalescence process is investigated in this study. Three kinds of chamber shapes (half-round, triangle and camber) are designed to realize head-on droplets coalescence. The coalescence processes are visualized with high-speed camera system and the internal flow patterns are resolved with micro-PIV system. Experimental analyses on droplets coalescence position, coalescence time and the critical conditions are discussed. Both direct coalescence and late coalescence can be observed in the camber junction while only the late coalescence is present for the half-round and the triangle junction. The critical capillary number Ca* varies for different working systems or intersection shapes. Ca* in the camber junction is larger than that in the other two junctions for each working system and it decreases with the increase of the viscosity ratios for each intersection shape. Moreover, the characteristics of the velocity fields for different coalescence cases are analyzed for in-depth understanding of the process. The authors do appreciate the financial support of No.11572013 of National Nature Scicence Funding of China.

  17. Optimization of Variable-Depth Liner Configurations for Increased Broadband Noise Reduction

    Science.gov (United States)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Schiller, N. H.; Born, J. C.

    2016-01-01

    This paper employs three acoustic propagation codes to explore variable-depth liner configurations for the NASA Langley Grazing Flow Impedance Tube (GFIT). The initial study demonstrates that a variable impedance can acceptably be treated as a uniform impedance if the spatial extent over which this variable impedance occurs is less than one-third of a wavelength of the incident sound. A constrained optimization study is used to design a variable-depth liner and to select an optimization metric. It also provides insight regarding how much attenuation can be achieved with variable-depth liners. Another optimization study is used to design a liner with much finer chamber depth resolution for the Mach 0.0 and 0.3 test conditions. Two liners are designed based on spatial rearrangement of chambers from this liner to determine whether the order is critical. Propagation code predictions suggest this is not the case. Both liners are fabricated via additive manufacturing and tested in the GFIT for the Mach 0.0 condition. Predicted and measured attenuations compare favorably across the full frequency range. These results clearly suggest that the chambers can be arranged in any order, thus offering the potential for innovative liner designs to minimize depth and weight.

  18. 超声乳化白内障吸出术对急性原发性闭角型青光眼眼前段的影响%Effects of anterior segment after phacoemulsification in patients with acute primary angle closure glaucoma

    Institute of Scientific and Technical Information of China (English)

    李乃洋; 赵岐; 钟兴武

    2011-01-01

    ),central anterior chamber depth (CACD),peripheral anterior chamber depth (PACD),anterior chamber volume (ACV),pupil diameter (PD),and anterior chamber angle (ACA) on cross- section photographs.Results Mean IOP decreased from preoperative (33.08 ± 5.21) mm Hg to postoperative (16.36±3.44) mm Hg (1 mm Hg=0.133 kPa,t=20.644,P=0.000) and CACD measurements increased from (1.79±0.20) mm to (3.41±0.38) mm (t=36.191,P=0.000).PACD deepened from (0.82±0.12) mm to (1.81±0.20) mm (t=40.732,P=0.000).ACV increased from (74.10±9.94) mm to (149.72±17.12) mm (t=54.921,P=0.000).Inferior ACA widened from (24.03±3.50)° to (43.29±3.92)° (t=55.489,P=0.000),and from (23.02±2.96)° to (42.36±4.61)° (t=43.291,P=0.000) in nasal direction.Superior ACA widened from (21.62±3.04)° to (39.66±3.53)° (t=43.511,P=0.000),and from (22.88±2.87)° to (41.21±3.81)° (t=44.930,P=0.000) in temporal direction.PD before and after phacoemulsification were (3.06± 1.32) mm and (3.00 ± 1.21) mm (t=1.177,P=0.247) respectively,with no statistic difference.Conclusions Phacoemulsification can widen the angle and lessen angle crowding in APACG patients.The Pentacam and AS-OCT allow easy,fast,automatic and noncontact quantification of the anterior chamber parameters with good prospects.

  19. Final report for NIF chamber dynamics studies

    Energy Technology Data Exchange (ETDEWEB)

    Burnham, A; Peterson, P F; Scott, J M

    1998-09-01

    The National Ignition Facility (NIF), a 1.8 MJ, 192 laser beam facility, will have anticipated fusion yields of up to 20 MJ from D-T pellets encased in a gold hohlraum target. The energy emitted from the target in the form of x rays, neutrons, target debris kinetic energy, and target shrapnel will be contained in a 5 m. radius spherical target chamber. various diagnostics will be stationed around the target at varying distances from the target. During each shot, the target will emit x rays that will vaporize nearby target facing surfaces including those of the diagnostics, the target positioner, and other chamber structures. This ablated vapor will be transported throughout the chamber, and will eventually condense and deposit on surfaces in the chamber, including the final optics debris shields. The research at the University of California at Berkeley relates primarily to the NIF chamber dynamics. The key design issues are the ablation of the chamber structures, transport of the vapor through the chamber and the condensation or deposition processes of those vaporized materials. An understanding of these processes is essential in developing a concept for protecting the fina optics debris shields from an excessive coating (> 10 A) of target debris and ablated material, thereby prolonging their lifetime between change-outs. At Berkeley, we have studied the physical issues of the ablation process and the effects of varying materials, the condensation process of the vaporized material, and design schemes that can lower the threat posed to the debris shields by these processes. The work or portions of the work completed this year have been published in several papers and a dissertation [l-5].

  20. 正常人眼前段组织与房角开放度数的关系%Relationship between Structure of Anterior Segment Tissue and Open Angle in Normal Subjects

    Institute of Scientific and Technical Information of China (English)

    曾阳发; 刘杏; 王涛; 李媚; 李彬彬; 何明光

    2009-01-01

    [Objective] To study the relationship between structure of anterior segment tissues and open angle(AA) in normal subjects.[Methods] A total of 211 eyes from 211 normal subjects were enrolled,whose anterior chambers and lens were scanned using anterior segment optical coherence tomography (AS-OCT).The measuring items included AA,anterior chamber depth (ACD),anterior chamber horizontal diameter (ACHD),anatomical anterior chamber depth (AACD),ciliary band length (CBL),iris thickness (IT),lens thickness (LT),lens position (LP) and lens anterior apex position (LAAP).The relationship between the 8 biometric parameters and AA was analyzed using linear correlation,respectively.[Results] The mean of AA was (40 ± 17)°,with (44 ± 18)° in male,and (37 ± 16)° in female.The difference of AA between male and female was statistically significant (t = 2.893,P = 0.004).There was significant correlation between AA and ACD (r = 0.721,P = 0.000),LT (r = -0.545,P = 0.000),CBL (r = 0.615,P = 0.000),LAAP (r = -0.717,P = 0.000),LP (r = 0.557,P = 0.000),and ACHD (r = 0.175,P = 0.011).There was no significant correlation between AA and AACD (r = 0.130,P = 0.059),IT (r = 0.129,P = 0.061).[Conclusion] The AA of females was narrower than that of males.In normal subjects,the most important factors which determine AA are the lens,the location of the peripheral iris and ciliary body.%[目的] 分析正常人房角开放度数(AA)与眼前段结构的关系. [方法] 收集211例(211只眼)正常人,采用眼前段光学相干断层扫描仪(AS-OCT)扫描其前房和晶状体,并测量前房深度(ACD)、前房横径(ACHD)、解剖前房深度(AACD)、睫状体带长度(CBL)、虹膜厚度(IT)、晶状体厚度(LT)、晶状体位置(LP)以及晶状体前极的位置(LAAP).采用直线相关分析这8个参数与AA的关系. [结果] AA的均值为(40 ± 17)°,男性(44 ± 18)°,女性(37 ± 16)°,比较差异有统计学意义(t = 2.893,P = 0.004).AA

  1. Technique for routine output verification of Leipzig applicators with a well chamber.

    Science.gov (United States)

    Pérez-Calatayud, J; Granero, D; Ballester, F; Crispín, V; Van der Laarse, R

    2006-01-01

    The H-type Leipzig applicators are accessories of the microSelectron-HDR system (Nucletron, Veenendaal, The Netherlands) for treatment of superficial malignancies. Recently, the dose rate distributions in liquid water for the whole set of applicators using both source models available for the microSelectron-HDR afterloaders have been obtained by means of the experimentally validated Monte Carlo (MC) code GEANT4. Also an output table (cGy/hU) at 3 mm depth on the applicator central axis was provided. The output verification of these applicators by the user, prior to their clinical use, present practical problems: small detectors such as thermoluminescent dosimeters or parallel-plate ionization chambers are not easily used for verification in a clinical environment as they require a rigid setup with the Leipzig applicator and a phantom. In contrast, well-type ionization chambers are readily available in radiotherapy departments. This study presents a technique based on the HDR1000Plus well chamber (Standar Imaging) measurements with a special insert, which allows the output verification of the H-type Leipzig applicators on a routine basis. This technique defines correspondence factors (CF) between the in water dose rate output of the Leipzig applicators (cGy/hU) obtained with MC and the reading on the well chamber with the special insert, normalized to the HDR calibration factor with the HDR insert and to the source strength. To commission the applicators (with the well chamber and the special insert used), the physicist should check if the CF value agrees with its tabulated values presented in this work. If the differences are within 5% the tabulated output values can be used in clinical dosimetry. This technique allows the output validation of the Leipzig applicators with a well chamber widely used for HDR Ir-192 source strength measurements. It can easily be adapted to other types of well chambers for HDR source output verification.

  2. Investigation of Swirling Flows in Mixing Chambers

    Directory of Open Access Journals (Sweden)

    Jyh Jian Chen

    2011-01-01

    Full Text Available This investigation analyzed the three-dimensional momentum and mass transfer characteristics arising from multiple inlets and a single outlet in micromixing chamber. The chamber consists of a right square prism, an octagonal prism, or a cylinder. Numerical results which were presented in terms of velocity vector plots and concentration distributions indicated that the swirling flows inside the chamber dominate the mixing index. Particle trajectories were utilized to demonstrate the rotational and extensional local flows which produce steady stirring, and the configuration of colored particles at the outlet section expressed at different Re represented the mixing performance qualitatively. The combination of the Taylor dispersion and the vorticity was first introduced and made the mixing successful. The effects of various geometric parameters and Reynolds numbers on the mixing characteristics were investigated. An optimal design of the cylindrical chamber with 4 inlets can be found. At larger Reynolds number, Re>15, more inertia caused the powerful swirling flows in the chamber, and more damping effect on diffusion was diminished, which then increased the mixing performance.

  3. Improved climatic chamber for desiccation simulation

    Directory of Open Access Journals (Sweden)

    Lozada Catalina

    2016-01-01

    Full Text Available The climatic chamber at the Universidad de Los Andes was improved for modeling desiccation in soil layers. This chamber allows the measurement of different environmental variables. In this research, evaporation tests were conducted in water imposing boundary conditions for drying, and then these tests were performed in a soil layer. The soil was prepared from a slurry state and was drying controlling the temperature, the infrared radiation, the wind velocity, and the relative humidity. In the first part of this paper, a description of the climatic chamber, operation ranges and theoretical work principles of the climatic chamber are presented. Then, the second part shows the results for desiccation in water and soil. The desiccation tests performed with the climatic chamber allow simulating all environmental conditions accurately during drying coupling the effect of all environmental variables. As a result, the evaporation rate increases with infrared radiation in soil and water. The rate at the beginning of the desiccation tests in clays is the same as in water. However, this evaporation rate decreases as the soil becomes desiccated.

  4. Tuned Chamber Core Panel Acoustic Test Results

    Science.gov (United States)

    Schiller, Noah H.; Allen, Albert R.

    2016-01-01

    This report documents acoustic testing of tuned chamber core panels, which can be used to supplement the low-frequency performance of conventional acoustic treatment. The tuned chamber core concept incorporates low-frequency noise control directly within the primary structure and is applicable to sandwich constructions with a directional core, including corrugated-, truss-, and fluted-core designs. These types of sandwich structures have long, hollow channels (or chambers) in the core. By adding small holes through one of the facesheets, the hollow chambers can be utilized as an array of low-frequency acoustic resonators. These resonators can then be used to attenuate low-frequency noise (below 400 Hz) inside a vehicle compartment without increasing the weight or size of the structure. The results of this test program demonstrate that the tuned chamber core concept is effective when used in isolation or combined with acoustic foam treatments. Specifically, an array of acoustic resonators integrated within the core of the panels was shown to improve both the low-frequency absorption and transmission loss of the structure in targeted one-third octave bands.

  5. Rejection of partial-discharge-induced pulses in fission chambers designed for sodium-cooled fast reactors

    Science.gov (United States)

    Hamrita, H.; Jammes, C.; Galli, G.; Laine, F.

    2017-03-01

    Under given temperature and bias voltage conditions, partial discharges can create pulses in fission chambers. Based on experimental results, this phenomenon is in-depth investigated and discussed. A pulse-shape-analysis technique is proposed to discriminate neutron-induced pulses from partial-discharge-induced ones.

  6. [Surgical anatomy of the anterior mediastinum].

    Science.gov (United States)

    Biondi, Alberto; Rausei, Stefano; Cananzi, Ferdinando C M; Zoccali, Marco; D'Ugo, Stefano; Persiani, Roberto

    2007-01-01

    The mediastinum is located from the thoracic inlet to the diaphragm between the left and right pleural cavities and contains vital structures of the circulatory, respiratory, digestive, and nervous system. Over the years, since there are no fascial or anatomic planes, anatomists and radiologists have suggested various schemes for subdividing the mediastinum and several anatomical and radiological classifications of the mediastinum are reported in the literature. The most popular of these scheme divides medistinum, for purposes of description, into two parts: an upper portion, above the upper level of the pericardium, which is named the superior mediastinum; and a lower portion, below the upper level of the pericardium. For clinical purposes, the mediastinum may be subdivided into three major areas, i.e. anterior, middle, and posterior compartments. The anterior mediastinum is defined as the region posterior to the sternum and anterior to the heart and brachiocephalic vessels. It extends from the thoracic inlet to the diaphragm and contains the thymus gland, fat, and lymph nodes. This article will review surgical anatomy of the anterior mediastinum and will focus on the surgical approch to anterior mediastinum and thymic diseases.

  7. High intensity electromagnetic field gerenation using a transportable reverberation chamber

    NARCIS (Netherlands)

    Leferink, Frank

    2008-01-01

    A reverberation chamber can create very high field strength with moderate input power. Existing chambers are making use of a paddle wheel to change the resonant modes in the chamber. A transportable reverberation chamber with vibrating walls will be presented. Inside this Vibrating Intrinsic Reverbe

  8. Ultrasound biomicroscopy in the comparison of the anterior segment morphometry before and after pars plana vitrectomy Biomicroscopia ultra-sônica na comparação da morfometria do segmento anterior antes e após vitrectomia "pars plana"

    Directory of Open Access Journals (Sweden)

    Flavio de Andrade Marigo

    2006-12-01

    Full Text Available PURPOSE: To determine if pars plana vitrectomy induces long-term changes in the anterior segment anatomy by means of ultrasound biomicroscopy. METHODS: A prospective case series study was undertaken of consecutive patients referred to a tertiary eye care centre for pars plana vitrectomy as the only procedure. Twenty eyes of 20 patients undergoing pars plana vitrectomy alone were studied by ultrasound biomicroscopy. Silicone oil or scleral buckle was not used in any of the included cases. The following morphometric parameters were compared before and after 3 months of surgery: anterior chamber depth, angle-opening distance at 500 µm from the scleral spur, trabecular-ciliary process distance, ciliary body thickness at 1, 2 and 3 millimeters from the scleral spur and measurement of the supraciliary space thickness, when fluid was detected. RESULTS: No statistically significant differences were found between the preoperative and the postoperative morphometric parameters. CONCLUSION: Uncomplicated pars plana vitrectomy does not induce any long-term change on anterior segment morphometry. Based on these findings, the normal long-term pattern to be expected after pars plana vitrectomy is the conservation of the preoperative morphometry.OBJETIVOS: O objetivo do presente estudo foi determinar, por meio da biometria ultra-sônica (UBM, se a vitrectomia via "pars plana" pode induzir alterações permanentes na anatomia do segmento anterior. MÉTODOS: Foi realizado estudo prospectivo, analisando-se uma série consecutiva de pacientes, encaminhados para um centro de referência terciário para serem submetidos a vitrectomia via "pars plana" como único procedimento. Vinte olhos de 20 pacientes a serem submetidos a vitrectomia como único procedimento foram estudados pela biomicroscopia ultra-sônica. Óleo de silicone ou introflexão escleral não foram usados em nenhum dos casos incluídos. Os seguintes parâmetros morfométricos foram comparados antes e

  9. Thermal vacuum chamber repressurization with instrument purging

    Science.gov (United States)

    Woronowicz, Michael S.

    2016-09-01

    At the conclusion of cryogenic vacuum testing of the James Webb Space Telescope Optical Telescope Element Integrated Science Instrument Module (JWST-OTIS) in NASA Johnson Space Center's (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are postulating that chamber particulate material stirred up by the repressurization process may be kept from falling into the Integrated Science Instrument Module (ISIM) interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This manuscript describes development of a series of models designed to describe this process. The models are strung together in tandem with a fictitious set of conditions to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.

  10. Rapid-Cycling Bubble-Chamber, details

    CERN Multimedia

    1980-01-01

    Parts of the hydraulic expansion system of the Rapid-Cycling Bubble-Chamber (RCBC). RCBC was the largest of 3 rapid-cycling bubble-chambers (the others were LEBC and HOLEBC), used as target- and vertex-detectors within the European Hybrid Spectrometer (EHS) in the SPS North Area (EHN1). RCBC contained 250 l of liquid hydrogen and was located inside a 3 T superconducting magnet. It was designed for 30 expansions/s (100 times faster than BEBC), the system shown here allowed 50 expansions/s. RCBC operated from 1981 to 1983 for experiments NA21, NA22 and NA23 at a rate of 15 expansions/s, clocking up a total of over 4 million. In the rear, at left, is bearded Lucien Veillet; Augustin Didona is at the right. See also 8001009. The installation of the piston assembly in the RCBC chamber body is shown in the Annual Report 1980, p.65.

  11. Classification of the LHC BLM Ionization Chamber

    CERN Document Server

    Stockner, M; Fabjan, Christian Wolfgang; Holzer, E B; Kramer, Daniel

    2008-01-01

    The LHC beam loss monitoring (BLM) system must prevent the super conducting magnets from quenching and protect the machine components from damage. The main monitor type is an ionization chamber. About 4000 of them will be installed around the ring. The lost beam particles initiate hadronic showers through the magnets and other machine components. These shower particles are measured by the monitors installed on the outside of the accelerator equipment. For the calibration of the BLM system the signal response of the ionization chamber is simulated in GEANT4 for all relevant particle types and energies (keV to TeV range). For validation, the simulations are compared to measurements using protons, neutrons, photons and mixed radiation fields at various energies and intensities. This paper will focus on the signal response of the ionization chamber to various particle types and energies including space charge effects at high ionization densities.

  12. Posing the first LEAR vacuum chamber

    CERN Multimedia

    1982-01-01

    The photo shows one of the four bending magnets of LEAR. They were of C-type with the opening ('mouth') to the outside of the ring (yoke to the inside). Last preparations are made before the vacuum chamber is slid through the mouth into the magnet. Stochastic cooling pickups/kickers were installed inside the chamber. One can distinguish a large number of feed-throughs on the chamber (leading to the pickup/kicker gaps). The free space in the middle of the block was left to offer room for an internal target in the magnet. This possibility was never exploited. Instead it is used here, to accommodate a pumping port for the high vacuum system. Michel Chanel (left) and Pierre Lefevre admire the mechanics at work.

  13. Synchronization of the CMS Cathode Strip Chambers

    CERN Document Server

    Raknessa, G; Wang, D

    2007-01-01

    The synchronization of the trigger and data acquisition systems for the Cathode Strip Chambers (CSCs) in the Compact Muon Solenoid (CMS) detector at CERN is described. The CSC trigger system is designed to trigger CMS on muons with high efficiency (~99% per chamber) and is able to accurately identify its 25ns proton bunch crossing. To date, asynchronous cosmic ray data have been used to define the protocol and to refine timing algorithms, allowing synchronization to be realized within and between chambers to within ±10 ns. Final synchronization of the CSCs requires timing parameters to be accurate to 2 ns. This goal will be readily achieved from the cosmic ray baseline using data taken with the synchronous beam structure of the Large Hadron Collider.

  14. Comparison of anterior segment parameters with Lenstar 900 and Sirius system%Sirius系统与Lenstar 900测量眼前节参数的比较研究

    Institute of Scientific and Technical Information of China (English)

    赵艳; 韦伟; 张长宁

    2014-01-01

    目的:比较两种非接触眼生物测量仪Lenstar 900( LS900)和Sirius眼前节分析系统测量眼前节有关参数的异同。  方法:对近视患者54例87眼分别采用LS900及Sirius系统测量角膜中央厚度( central corneal thickness, CCT)、前房深度(aqueous depth, ACD)、角膜平K(flat keratometry, FK)、角膜陡 K(steep keratometry,SK)、白到白(white to white, WTW)。采用配对 t 检验、Pearson 相关和 Bland-Altman图分析和评估。  结果:Sirius系统检测的CCT和ACD大于LS900,而FK、SK和 WTW 小于 LS900,差值的均值分别为-6.11±6.32μm;-0.09±0.07 mm;0.18±0.25 D;0.21±0.36 D 和0.25±0.39mm,差异有统计学意义(P  结论:LS900和Sirius系统对眼前节参数的检测具有良好的相关性和一致性,但也存在一定差异。这可能与Lenstar和Sirius测量方式并不一致有关,因此还有待进一步研究。%AlM: To compare the anterior segment measurements derived from optical low coherence reflectometer ( Lenstar LS900 ) and combined Scheimpflug - Placido disk topographer ( Sirius) . METHODS: ln this study, we enrolled healthy myopic subjects 54 ( 87 eyes ) . The central corneal thickness (CCT), anterior chamber depth (ACD), flat keratometry ( FK) readings , steep keratometry ( SK ) readings and white to white ( WTW ) were measured by LS900 and Sirius. Evaluation and analysis were performed using paired t tests, the Pearson correlation, and Bland-Altman analyses. RESULTS: The CCT and ACD measurements were significantly lower whereas FK, SK and WTW measurements were higher with LS900 (P CONCLUSlON: Anterior segment parameters evaluated with LS900 and Sirius systemare correlated well and achieve good agreement. However, there are significantly statistical differences which may be caused by the different measurement modes, so they may not be interchangeable use under certain clinical circumstances.

  15. THYMOLIPOMA: A RARE, LARGE ANTERIOR MEDIASTINAL MASS

    Directory of Open Access Journals (Sweden)

    Premananth

    2015-07-01

    Full Text Available Thymolipoma is a rare benign tumor of anterior mediastinum, described by Lange in 1916. 1 Less than 200 cases have been reported worldwide. 2 It accounts for 2% to 9% of thymic tumours. 3 We report a case of thymolipoma in a 37 year s old male patient, who pre sented with cough, dys p nea, chest pain for 2 months. CT THORAX revealed a large anterior mediastinal mass extending in to right hemithorax arising from thymus gland, with multiple areas of fat density, no significant mediastinal adenopathy, complete collap se of right middle and lower lobe suggestive of thymolipoma. CT guided biopsy suggestive of thymic neoplasm. The tumour was removed enbloc through surgery. Histopathological examination of large mass lesion confirmed thymolipoma. We report this case to emp hasize the importance of considering thymolipoma as a differential diagnosis of anterior mediastinal mass, although rare.

  16. Esthetic crown lengthening for maxillary anterior teeth.

    Science.gov (United States)

    Sonick, M

    1997-08-01

    In the maxillary anterior region, the gingival labial margin position is an important parameter in the achievement of an ideal smile. The relationship between the periodontium and the restoration is critical if gingival health and esthetics are to be achieved. Periodontal therapy is a necessary and useful adjunct when any anterior restoration is undertaken. Anterior surgical crown lengthening may be undertaken to avoid restorative margin impingement on the biologic width. Crown lengthening is also used to alter the gingival labial profiles. This article discusses the esthetic parameters of ideal gingival labial positions and presents a classification of crown-lengthening procedures and the procedure for a two-stage crown-lengthening technique. The two-stage crown-lengthening technique is surgically precise because healing is predictable.

  17. Evaluation of Descemet’s Membrane Detachment Using Anterior Segment Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Halil Hüseyin Çağatay

    2014-10-01

    Full Text Available We report the use of anterior segment optical coherence tomography (ASOCT in Descemet’s membrane detachment (DMD. A patient who developed DMD after uneventful cataract surgery with posterior chamber lens implantation is presented in this case report. At the follow-up examination after cataract surgery, slit-lamp evaluation showed stromal striae, but it was impossible to diagnose the DMD due to the corneal edema. ASOCT imaging of the cornea revealed a DMD, and the patient underwent intracameral air injection to the anterior chamber through the site which was identified as intact by ASOCT. Follow-up ASOCT imaging revealed the reattachment of the Descemet’s membrane and reduced corneal thickness. If DMD is suspected in any cases, ASOCT can be useful to document and follow the postsurgical detachment of DMD and also to determine the site, configuration, and extent of the DMD, thus guiding the treatment method and monitoring the treatment outcome. (Turk J Ophthalmol 2014; 44: 407-9

  18. Calibration of a pencil ionization chamber with and without preamplifier

    OpenAIRE

    Maia, Ana Figueiredo

    2004-01-01

    The pencil ionization chamber is a cylindrical dosimeter developed for computed tomography beams. Many kinds of ionization chambers have a preamplifier connected to the chamber to make it electrically more stable, specially for field instruments. In this study, the performance of a Victoreen pencil ionization chamber with the original preamplifier and after its removal was compared. The objective of the preamplifier removal was to enable connecting the chamber to other kinds of electromete...

  19. Nonnecrotizing anterior scleritis mimicking orbital inflammatory disease

    Directory of Open Access Journals (Sweden)

    Lynch MC

    2013-08-01

    Full Text Available Michelle Chen Lynch,1 Andrew B Mick21Optometry Clinic, Ocala West Veterans Affairs Specialty Clinic, Ocala, FL, USA; 2Eye Clinic, San Francisco VA Medical Center, San Francisco, CA, USABackground: Anterior scleritis is an uncommon form of ocular inflammation, often associated with coexisting autoimmune disease. With early recognition and aggressive systemic therapy, prognosis for resolution is good. The diagnosis of underlying autoimmune disease involves a multidisciplinary approach.Case report: A 42-year-old African American female presented to the Eye Clinic at the San Francisco Veteran Affairs Medical Center, with a tremendously painful left eye, worse on eye movement, with marked injection of conjunctiva. There was mild swelling of the upper eyelid. Visual acuity was unaffected, but there was a mild red cap desaturation. The posterior segment was unremarkable. The initial differential diagnoses included anterior scleritis and orbital inflammatory disease. Oral steroid treatment was initiated with rapid resolution over a few days. Orbital imaging was unremarkable, and extensive laboratory work-up was positive only for antinuclear antibodies. The patient was diagnosed with idiopathic diffuse, nonnecrotizing anterior scleritis and has been followed for over 5 years without recurrence. The rheumatology clinic monitors the patient closely, as suspicion remains for potential arthralgias including human leukocyte antigen-B27-associated arthritis, lupus-associated arthritis, seronegative rheumatoid arthritis, recurrent juvenile idiopathic arthritis, and scleroderma, based on her constitutional symptoms and clinical presentation, along with a positive anti-nuclear antibody lab result.Conclusion: Untreated anterior scleritis can progress to formation of cataracts, glaucoma, uveitis, corneal melting, and posterior segment disease with significant risk of vision loss. Patients with anterior scleritis must be aggressively treated with systemic anti

  20. Ultra-low mass drift chambers

    Energy Technology Data Exchange (ETDEWEB)

    Assiro, R. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Cappelli, L. [Università di Cassino e del Lazio Meridionale (Italy); Cascella, M. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Dipartimento Matematica e Fisica, Università del Salento (Italy); De Lorenzis, L. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Dipartimento di Ingegneria dell' Innovazione, Università del Salento (Italy); Grancagnolo, F. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Ignatov, F. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); L' Erario, A.; Maffezzoli, A. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Dipartimento di Ingegneria dell' Innovazione, Università del Salento (Italy); Miccoli, A. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Onorato, G. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Università G. Marconi, Roma (Italy); Perillo, M. [EnginSoft S.p.a., Trento (Italy); Piacentino, G. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Fermilab, Batavia, IL (United States); Università G. Marconi, Roma (Italy); Rella, S. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Dipartimento di Ingegneria dell' Innovazione, Università del Salento (Italy); Rossetti, F. [EnginSoft S.p.a., Trento (Italy); Spedicato, M. [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Tassielli, G., E-mail: giovanni.tassielli@le.infn.it [Istituto Nazionale di Fisica Nucleare, Lecce (Italy); Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Università G. Marconi, Roma (Italy); and others

    2013-08-01

    We present a novel low mass drift chamber concept, developed in order to fulfill the stringent requirements imposed by the experiments for extremely rare processes, which require high resolutions (order of 100–200 keV/c) for particle momenta in a range (50–100 MeV/c) totally dominated by the multiple scattering contribution. We describe a geometry optimization procedure and a new wiring strategy with a feed-through-less wire anchoring system developed and tested on a drift chamber prototype under completion at INFN-Lecce.

  1. A view inside the Gargamelle bubble chamber

    CERN Multimedia

    1970-01-01

    Gargamelle was the name given to a big bubble chamber built at the Saclay Laboratory in France during the late 1960s. It was designed principally for the detection at CERN of the elusive particles called neutrinos. A bubble chamber contains a liquid under pressure, which reveals the tracks of electrically charged particles as trails of tiny bubbles when the pressure is reduced. Neutrinos have no charge, and so leave no tracks, but the aim with Gargamelle was "see neutrinos" by making visible any charged particles set in motion by the interaction of neutrinos in the liquid

  2. Cosmic Muon Detector Using Proportional Chambers

    CERN Document Server

    Varga, Dezső; Hamar, Gergő; Molnár, Janka Sára; Oláh, Éva; Pázmándi, Péter

    2015-01-01

    A set of classical multi-wire proportional chambers were designed and constructed with the main purpose of efficient cosmic muon detection. These detectors are relatively simple to construct, and at the same time are low cost, making them ideal for educational purposes. The detector layers have efficiencies above 99% for minimum ionizing cosmic muons, and their position resolution is about 1 cm, that is, particle trajectories are clearly observable. Visualization of straight tracks is possible using an LED array, with the discriminated and latched signal driving the display. Due to the exceptional operating stability of the chambers, the design can also be used for cosmic muon telescopes.

  3. Anterior ischemic optic neuropathy following dengue fever.

    Science.gov (United States)

    Ramakrishnan, Reshma; Shrivastava, Saurabh; Deshpande, Shrikant; Patkar, Priyanka

    2016-01-01

    Dengue fever is caused by a flavivirus. This infection is endemic in the tropics and warm temperate regions of the world. Ocular manifestations of dengue fever include subconjunctival, vitreous, and retinal haemorrhages; posterior uveitis; optic neuritis; and maculopathies, haemorrhage, and oedema. However anterior ischemic optic neuropathy is a rare presentation. Optic nerve ischemia most frequently occurs at the optic nerve head, where structural crowding of nerve fibers and reduction of the vascular supply may combine to impair perfusion to a critical degree and produce optic disc oedema. Here we present a case of anterior ischemic optic neurapathy associated with dengue fever.

  4. Study of aqueous humour in anterior uveitis

    Directory of Open Access Journals (Sweden)

    Kalsy Jairaj

    1990-01-01

    Full Text Available Aetiological diagnosis of anterior uveitis was made clinically and substantiated with relevant investigations. Aqueous humour obtained under aseptic conditions, was analyzed for the cells study, culture and protein profile, using polyacrylamide gel electrophoresis. The results were analysed with the help of known clinical facts. Culture and smears were invariably negative, while the lymphocytes were present in varying numbers, polymorphs and macrophages afforded a useful clue for confirmatory diagnosis. The electrophoretic pattern of the proteins was related to the duration of the disease and was same in a group while it was distinctive among different groups of anterior uveitis.

  5. ANTERIOR OSTEOPHYTE IDENTIFICATION IN CERVICAL VERTEBRAE

    Directory of Open Access Journals (Sweden)

    A. T. Chougale

    2011-06-01

    Full Text Available Radiologist always examines X-ray to determine abnormal changes in cervical, lumbar & thoracic vertebrae. Osteophyte (bony growth may appear at the corners of vertebrae so that vertebral shape becomes abnormal. This paper presents the idea from Image processing techniques such as customised Hough transform which will be used for segmentation which should be independent of rotation, scale, noise & shape. This segmented image will be then used for computing size invariant, convex hull based features to differentiate normal cervical vertebrae from cervical vertebrae containing anterior osteophyte. This approach effectively finds anterior osteophytes in cervical vertebrae.

  6. Dual (type IV left anterior descending artery

    Directory of Open Access Journals (Sweden)

    Ozdil Baskan

    2013-11-01

    Full Text Available Congenital coronary artery anomalies are uncommon. Dual left anterior descending coronary artery (LAD is defined as the presence of two LADs within the anterior interventricular sulcus (AIVS, and is classified into four types. Type IV is a rarely reported subtype and differs from the others, with a long LAD originating from the right coronary artery (RCA. Dual LAD is a benign coronary artery anomaly, but should be recognised especially before interventional procedures. With the increasing use of multidedector computed tomography (MDCT, it is essential for radiologists to be aware of this entity and the cross-sectional findings.

  7. Ultrasonic material hardness depth measurement

    Science.gov (United States)

    Good, Morris S.; Schuster, George J.; Skorpik, James R.

    1997-01-01

    The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part.

  8. Photon counting compressive depth mapping

    CERN Document Server

    Howland, Gregory A; Ware, Matthew R; Howell, John C

    2013-01-01

    We demonstrate a compressed sensing, photon counting lidar system based on the single-pixel camera. Our technique recovers both depth and intensity maps from a single under-sampled set of incoherent, linear projections of a scene of interest at ultra-low light levels around 0.5 picowatts. Only two-dimensional reconstructions are required to image a three-dimensional scene. We demonstrate intensity imaging and depth mapping at 256 x 256 pixel transverse resolution with acquisition times as short as 3 seconds. We also show novelty filtering, reconstructing only the difference between two instances of a scene. Finally, we acquire 32 x 32 pixel real-time video for three-dimensional object tracking at 14 frames-per-second.

  9. Applications of positron depth profiling

    Energy Technology Data Exchange (ETDEWEB)

    Hakvoort, R.A.

    1993-12-23

    In this thesis some contributions of the positron-depth profiling technique to materials science have been described. Following studies are carried out: Positron-annihilation measurements on neon-implanted steel; Void creation in silicon by helium implantation; Density of vacancy-type defects present in amorphous silicon prepared by ion implantation; Measurements of other types of amorphous silicon; Epitaxial cobalt disilicide prepared by cobalt outdiffusion. Positron-annihilation experiments on low-pressure CVD silicon-nitride films. (orig./MM).

  10. Underwater camera with depth measurement

    Science.gov (United States)

    Wang, Wei-Chih; Lin, Keng-Ren; Tsui, Chi L.; Schipf, David; Leang, Jonathan

    2016-04-01

    The objective of this study is to develop an RGB-D (video + depth) camera that provides three-dimensional image data for use in the haptic feedback of a robotic underwater ordnance recovery system. Two camera systems were developed and studied. The first depth camera relies on structured light (as used by the Microsoft Kinect), where the displacement of an object is determined by variations of the geometry of a projected pattern. The other camera system is based on a Time of Flight (ToF) depth camera. The results of the structural light camera system shows that the camera system requires a stronger light source with a similar operating wavelength and bandwidth to achieve a desirable working distance in water. This approach might not be robust enough for our proposed underwater RGB-D camera system, as it will require a complete re-design of the light source component. The ToF camera system instead, allows an arbitrary placement of light source and camera. The intensity output of the broadband LED light source in the ToF camera system can be increased by putting them into an array configuration and the LEDs can be modulated comfortably with any waveform and frequencies required by the ToF camera. In this paper, both camera were evaluated and experiments were conducted to demonstrate the versatility of the ToF camera.

  11. 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.

  12. Drift Chambers detectors; Detectores de deriva

    Energy Technology Data Exchange (ETDEWEB)

    Duran, I.; Martinez laso, L.

    1989-07-01

    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.

  13. A mathematical model of aerosol holding chambers

    DEFF Research Database (Denmark)

    Zak, M; Madsen, J; Berg, E

    1999-01-01

    , Ontario, Canada), NebuChamber (Astra, Södirtälje, Sweden) and Nebuhaler (Astra) adapted for babies. The dose of fluticasone proportionate delivered by the Babyhaler (Glaxco Wellcome, Oxbridge, Middlesex, UK) was 80% of that predicted, probably because of incomplete priming of this spacer. Of the above...

  14. Acoustical-Levitation Chamber for Metallurgy

    Science.gov (United States)

    Barmatz, M. B.; Trinh, E.; Wang, T. G.; Elleman, D. D.; Jacobi, N.

    1983-01-01

    Sample moved to different positions for heating and quenching. Acoustical levitation chamber selectively excited in fundamental and second-harmonic longitudinal modes to hold sample at one of three stable postions: A, B, or C. Levitated object quickly moved from one of these positions to another by changing modes. Object rapidly quenched at A or C after heating in furnace region at B.

  15. Prototype Vacuum Chamber for ISR Intersection Region

    CERN Multimedia

    1974-01-01

    The vacuum chambers at the ISR interaction region had to be as transparent as possible to the secondary particles emerging from the collision points. Made from stainless steel or titanium, only a fraction of a millimeter thick, they were most delicate to handle.

  16. Multiphysics Nuclear Thermal Rocket Thrust Chamber Analysis

    Science.gov (United States)

    Wang, Ten-See

    2005-01-01

    The objective of this effort is t o develop an efficient and accurate thermo-fluid computational methodology to predict environments for hypothetical thrust chamber design and analysis. The current task scope is to perform multidimensional, multiphysics analysis of thrust performance and heat transfer analysis for a hypothetical solid-core, nuclear thermal engine including thrust chamber and nozzle. The multiphysics aspects of the model include: real fluid dynamics, chemical reactivity, turbulent flow, and conjugate heat transfer. The model will be designed to identify thermal, fluid, and hydrogen environments in all flow paths and materials. This model would then be used to perform non- nuclear reproduction of the flow element failures demonstrated in the Rover/NERVA testing, investigate performance of specific configurations and assess potential issues and enhancements. A two-pronged approach will be employed in this effort: a detailed analysis of a multi-channel, flow-element, and global modeling of the entire thrust chamber assembly with a porosity modeling technique. It is expected that the detailed analysis of a single flow element would provide detailed fluid, thermal, and hydrogen environments for stress analysis, while the global thrust chamber assembly analysis would promote understanding of the effects of hydrogen dissociation and heat transfer on thrust performance. These modeling activities will be validated as much as possible by testing performed by other related efforts.

  17. IKAR, a ionization chamber for WA9

    CERN Document Server

    1976-01-01

    This ionization chamber arrived at CERN from Leningrad for a high precision study of hadron elastic scattering by a CERN-Clermont-Ferrand-Leningrad-Lyon-Uppsala Collaboration in the H3 beam (WA9). G.A. Korolev (third from right) looks at the drawings.

  18. Heat-barrier coatings for combustion chambers

    Science.gov (United States)

    Carpenter, H. W.

    1970-01-01

    Arc-plasma-sprayed layered coating of graded Inconel and zirconia protects film-coolant ring below injector plate of rocket engine combustion chamber. Interfacial temperature is designed for minimum buildup of stress and to avoid melting of the metal phase in the graded layers.

  19. Using reverberation chambers for EM measurements

    NARCIS (Netherlands)

    Leferink, Frank B.J.

    2010-01-01

    Reverberation chambers (RC) are being used for several decades. The main advantage is the high field strength which can be generated, with only modest power. In the last few years the use of RCs became much popular, for testing multi-path propagation for communication links, or testing the coupling

  20. Chamber transport for heavy ion fusion

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Craig L., E-mail: clolson66@msn.com

    2014-01-01

    A brief review is given of research on chamber transport for HIF (heavy ion fusion) dating from the first HIF Workshop in 1976 to the present. Chamber transport modes are categorized into ballistic transport modes and channel-like modes. Four major HIF reactor studies are summarized (HIBALL-II, HYLIFE-II, Prometheus-H, OSIRIS), with emphasis on the chamber transport environment. In general, many beams are used to provide the required symmetry and to permit focusing to the required small spots. Target parameters are then discussed, with a summary of the individual heavy ion beam parameters required for HIF. The beam parameters are then classified as to their line charge density and perveance, with special emphasis on the perveance limits for radial space charge spreading, for the space charge limiting current, and for the magnetic (Alfven) limiting current. The major experiments on ballistic transport (SFFE, Sabre beamlets, GAMBLE II, NTX, NDCX) are summarized, with specific reference to the axial electron trapping limit for charge neutralization. The major experiments on channel-like transport (GAMBLE II channel, GAMBLE II self-pinch, LBNL channels, GSI channels) are discussed. The status of current research on HIF chamber transport is summarized, and the value of future NDCX-II transport experiments for the future of HIF is noted.

  1. Precision electronics for ionization chamber measurements

    Energy Technology Data Exchange (ETDEWEB)

    Santry, D.C.; Bowes, G.C.; Munzenmayer, K.

    1987-01-01

    By using commercially available units, an electrometer and an IBM personal computer, it was relatively inexpensive and simple to assemble a system which permits ..gamma..-ray-emitting radionuclide activities to be measured in an ionization chamber with an uncertainty of + - 0.5% and a reproducibility of + - 0.05%.

  2. Isolation of Drosophila egg chambers for imaging.

    Science.gov (United States)

    Parton, Richard M; Vallés, Ana Maria; Dobbie, Ian M; Davis, Ilan

    2010-04-01

    The fruit fly Drosophila melanogaster is an important model for basic research into the molecular mechanisms underlying cell function and development, as well as a major biomedical research tool. A significant advantage of Drosophila is the ability to apply live cell imaging to a variety of living tissues that can be dissected and imaged in vivo, ex vivo, or in vitro. Drosophila egg chambers, for example, have proven to be a useful model system for studying border cell migration, Golgi unit transport, the rapid movement of mRNA and protein particles, and the role of microtubules in meiosis and oocyte differentiation. A crucial first step before imaging is preparation of the experimental material to ensure physiological relevance and to achieve the best conditions for image quality. Early- to mid-stage egg chambers cannot be mounted in an aqueous-based medium, because this causes a change in microtubule organization and follicle cell morphology. Such egg chambers survive better in Halocarbon oil, which allows free diffusion of oxygen, has low viscosity, and thus prevents dehydration and hypoxia. With a refractive index similar to glycerol, Halocarbon oil also has good optical properties for imaging. It also provides a good environment for injection and is particularly useful for long-term imaging of embryos. However, unlike with aqueous solutions, changes in the medium are not possible. This protocol describes the isolation of Drosophila egg chambers.

  3. The arrival of the CLOUD chamber

    CERN Multimedia

    CERN AVC

    2009-01-01

    The team from the CLOUD experiment - the world’s first experiment using a high-energy particle accelerator to study the climate - were on cloud nine after the arrival of their new three-metre diameter cloud chamber. This marks the end of three years’ R&D; and design, and the start of preparations for data taking later this year.

  4. Development of Master Chamber Software for Data Acquisition of Ionization Chamber for Indus 2 RRCAT

    OpenAIRE

    Priyesh Soni; Mrs. B. Harita; Nawaz Ali Sayed

    2013-01-01

    The main goal of this paper was to Develop Master control software for DAQ of ionization chamber for INDUS-2 beam lines for detection of X-ray flux by an Ionization chamber that will remotely control and monitor the ultra low current signal detection analog module precisely. This application will be useful to measure the intensity of X-ray flux through ionization chamber in a beam line of synchrotron radiation source which is mounted in INDUS-2. It is one of new technique of detection. Beam l...

  5. Causes of anterior cruciate ligament injuries

    Directory of Open Access Journals (Sweden)

    Ristić Vladimir

    2010-01-01

    Full Text Available In order to prevent anterior cruciate ligament injuries it is necessary to define risk factors and to analyze the most frequent causes of injuries - that being the aim of this study. The study sample consisted of 451 surgically treated patients, including 400 sportsmen (65% of them being active and 35% recreational sportsmen, 29% female and 71% male; of whom 90% were younger than 35. Sports injuries, as the most frequent cause of anterior cruciate ligament injuries, were recorded in 88% of patients (non-contact ones in 78% and contact ones in 22%, injuries occurring in everyday activities in 11% and in traffic in 1%. Among sportsmen, reconstruction of the anterior cruciate ligament was most frequently performed in football players (48%, then in handball players (22%, basketball players (13%, volleyball players (8%, martial arts fighters (4%. However, the injury incidence was the highest among the active basketball players (1 injured among 91 active players. Type of footwear, warming up before the activity, genetic predisposition and everyday therapy did not have a significant influence on getting injured. Anterior cruciate ligament injuries happened three times more often during matches, in the middle and at the end of a match and training session (79%, at landing after the jump or when changing direction of movement (75% without a contact with other competitors, on dry surfaces (79%, among not so well prepared sportsmen.

  6. ANTERIOR COLUMN FRACTURES OF THE ACETABULUM

    NARCIS (Netherlands)

    HEEG, M; OTTER, N; KLASEN, HJ

    1992-01-01

    We retrospectively reviewed 20 patients at three to 19 years after displaced anterior fracture-dislocations of the hip. Eighteen of them were treated by traction, after ensuring that the femoral head was adequately reduced beneath the undisrupted part of the weight-bearing dome. Two required operati

  7. Balanitis xerotica obliterans involving anterior urethra.

    Science.gov (United States)

    Herschorn, S; Colapinto, V

    1979-12-01

    Balanitis xerotica obliterans (BXO) is known to affect the urethral meatus, glans, and prepuce. We describe a case of biopsy-proved BXO that involves not only the usual areas but the anterior urethra as well. Of added interest is the subsequent development of squamous cell carcinoma in the fossa navicularis. The literature is reviewed.

  8. Treatment for acute anterior cruciate ligament tear

    DEFF Research Database (Denmark)

    Frobell, Richard B; Roos, Harald P; Roos, Ewa M;

    2013-01-01

    To compare, in young active adults with an acute anterior cruciate ligament (ACL) tear, the mid-term (five year) patient reported and radiographic outcomes between those treated with rehabilitation plus early ACL reconstruction and those treated with rehabilitation and optional delayed ACL...

  9. Guideline on anterior cruciate ligament injury

    NARCIS (Netherlands)

    Meuffels, Duncan E; Poldervaart, Michelle T; Diercks, Ronald; Fievez, Alex W F M; Patt, Thomas W; Hart, Cor P van der; Hammacher, Eric R; Meer, Fred van der; Goedhart, Edwin A; Lenssen, Anton F; Muller-Ploeger, Sabrina B; Pols, Margreet A; Saris, Daniel B F

    2012-01-01

    The Dutch Orthopaedic Association has a long tradition of development of practical clinical guidelines. Here we present the recommendations from the multidisciplinary clinical guideline working group for anterior cruciate ligament injury. The following 8 clinical questions were formulated by a steer

  10. Novel Insights into Anterior Cruciate Ligament Injury

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan)

    2011-01-01

    textabstractAnterior cruciate ligament (ACL) injury is one of the most common sports injuries of the knee. ACL reconstruction has become, standard orthopaedic practice worldwide with an estimated 175,000 reconstructions per year in the United States.6 The ACL remains the most frequently studied liga

  11. Treatment for acute anterior cruciate ligament tear

    DEFF Research Database (Denmark)

    Frobell, Richard B; Roos, Harald P; Roos, Ewa M;

    2015-01-01

    STUDY QUESTION: In young active adults with an acute anterior cruciate ligament (ACL) rupture, do patient reported or radiographic outcomes after five years differ between those treated with rehabilitation plus early ACL reconstruction and those treated with rehabilitation and optional delayed ACL...

  12. 飞秒激光制瓣LASIK术后眼前节参数的变化%Changes of the parameters of anterior segment of eyes after femtosecond laser LASIK

    Institute of Scientific and Technical Information of China (English)

    胡正再; 张薇; 王志军

    2016-01-01

    Objective To analyze the changes of the parameters of anterior segment of eyes after femtosecond laser LASIK.Methods In this prospective clinic study,50 eyes of 25 patients who underwent femtosecond laser laser in situ keratomileusis (LASIK) were included.The corneal endothelium density,anterior chamber depth,anterior chamber angle width,posterior corneal surface height (4 mm diameter),distance between pupil center and corneal vertex,pupil diameter under light and dark environment were compared before and 6 months or more after surgery.Distance between pupil center and corneal vertex using absolute value.Data were analyzed using paired t test.Results After surgery,comeal endothelium density (2 829.7±227.2 cells/mm2 vs.2 716.4±255.2 cells/mm2),anterior chamber depth(3.18±0.19 mm vs.3.08±0.21 mm),anterior chamber angle width (39.39°±3.90°,37.92° ±3.76°) decreased (t=3.077,11.079,5.241,P<0.01).The differences of posterior corneal surface height (4 mm diameter),pupil diameter under light and dark environment before and after surgery were insignificant.The distance between pupil center and corneal vertex on X axis increased (0.11±0.10 mm vs.0.14±0.12 mm,t=-3.318,P<0.01).The distance between pupil center and corneal vertex on Y axis increase (0.11±0.08 mm vs.0.15±0.11 mm,t=-4.157,P<0.01).Conclusion The parameters of anterior segment of eyes after femtosecond laser LASIK changed obviously,especially for the distance between pupil center and corneal vertex.Maybe this change is important in guiding the following surgery.%目的 分析飞秒激光制瓣LASIK术后眼前节各参数(前房深度、前房角宽度、4 mm范围角膜后表面最高值、瞳孔中心与角膜顶点距离)的变化.方法 前瞻性临床研究.接受飞秒制瓣LASIK手术的患者25例(50眼),记录并分析术前和术后6个月以上中央角膜内皮细胞计数、前房深度、前房角宽度、4 mm范围角膜后表面最高值、瞳孔中心与角膜顶点距离、明

  13. Perawatan Ortodontik Gigi Anterior Berjejal dengan Tulang Alveolar yang Tipis

    Directory of Open Access Journals (Sweden)

    Miesje K. Purwanegara

    2015-09-01

    Full Text Available Anterior teeth movement in orthodontic treatment is limited to labiolingual direction by very thin alveolar bone. An uncontrolled anterior tooth movement to labiolingual direction can cause alveolar bone perforation at its root segment. This case report is to remind us that alveolar bone thickness limits orthodontc tooth movement. A case of crowded anterior teeth with thin alveolar bone in malocclusion I is reported. This case is treated using adgewise orthodontic appliance. Protraction of anterior teeth is anticipated due to thin alveolar bone on the anterior surface. The conclusion is although the alveolar bone surrounding the crowded anterior teeth is thin, by controlling the movement the teeth reposition is allowed.

  14. Windows Into an Open-System Magma Chamber: Cognate Xenoliths From the Kameni Islands, Santorini, Greece

    Science.gov (United States)

    Martin, V. M.; Holness, M. B.; Pyle, D. M.

    2003-12-01

    recent eruptions on Santorini by approximately 20 months. This activity may signify the movement of magma at depth and the injection of new magma into the dacite chamber. Plagioclase crystal sizes in the quench xenoliths are consistent with growth timescales of the order of a few years, suggesting that these xenoliths derive from the replenishing magma. We suggest that replenishing material exists as a series of sills at the base of the chamber, with later pulses of magma intruding into, and disrupting, the pre-existing crystal pile. The concentration of cumulate xenoliths in the 1950 flow suggests that the replenishment event prior to this eruption intruded through a mature layer of crystal mush.

  15. Results of Posterior Chamber Lens Implantation for Correction of Myopia

    Directory of Open Access Journals (Sweden)

    Pınar Sorgun Evcili

    2012-10-01

    Full Text Available Pur po se: To evaluate the results of posterior chamber phakic intraocular lens implantation in myopic patients. Ma te ri al and Met hod: Posterior chamber phakic intraocular lens (STAAR ICL implantation was performed in 58 eyes of 33 patients with mean spherical equivalent of -13.12±5.31 diopters (D (-2.5 - -24.75 D between August 2007 and October 2010 at Dr. Lütfi Kırdar Kartal Training and Research Hospital, Second Eye Clinic. The mean age of the patients was 32.84 ± 9.95 years (18-55 years - 24 (72.7% were male and 9 (27.3% were female. The study was designed as prospective case series. The patients were evaluated regarding visual acuity, refraction, endothelial cell count, and complications in postoperative period. Re sults: The mean follow-up time was 21.5±4.9 (12-24 months months. The mean spherical equivalent was -1.29±1.53 D (-5.6 D - +2.60 D at the last postoperative follow-up visit. Visual acuity was better or equal to preoperative best-corrected value in 42 (72.4% of eyes at the last follow-up visit postoperatively. Mean spherical equivalent was regressed to -1.13±1.59D at 1-month and -1.39±1.53D at 24-month postoperative follow-up visit. Pupillary-block glaucoma in 1 eye (1.7%, anterior subcapsular opacification not affecting the vision in 4 eyes, and retinal detachment in 1 eye were detected at follow-up visits. Dis cus si on: ICL implantation was observed to be an effective and safe method for correction of myopia in two-year follow-up. As possible retinal complications may develop, the patients must be followed carefully during the preoperative and postoperative period. (Turk J Ophthalmol 2012; 42: 349-54

  16. Achievable field strength in reverberation chambers

    Directory of Open Access Journals (Sweden)

    N. Eulig

    2003-01-01

    Full Text Available Feldvariable Kammern (FVK, engl.: modestirred- chamber werden unter anderem für EMV-Störfestigkeitsprüfungen verwendet. Ein häufig genanntes Argument, das die Einführung dieser Kammern als normgerechte Prüfumgebung vorantreiben soll, ist eine hohe Feldstärke, die im Vergleich zu anderen Testumgebungen mit relativ moderaten HF-Leistungen erreicht werden kann. Besonders für sicherheitskritische Geräte, wie Komponenten aus der Avionik- oder KFZ-Industrie, sind heutzutage Testfeldstärken von mehreren 100 V/m notwendig. Derart hohe Feldstärken können in Umgebungen, die ein ebenes Wellenfeld erzeugen oder nachbilden, nur mit großen HFLeistungen generiert werden. Durch die Resonanzeigenschaften einer FVK können demgegenüber mit sehr viel weniger Leistung und damit Verstärkeraufwand vergleichbare Werte der Feldstärke erzeugt werden. Allerdings sinkt mit zunehmendem Volumen die erreichbare Feldstärke bei gleicher Speiseleistung. Idealerweise sollen Feldvariable Kammern bei möglichst niedrigen Frequenzen für EMVTests nutzbar sein, was jedoch ein großes Kammervolumen erfordert. Das Problem, bei niedrigen Frequenzen hohe Feldstärken erzeugen zu können, relativiert deshalb den Vorteil von FVKn gegenüber bekannten Testumgebungen bei niedrigen Testfrequenzen. Der Posterbeitrag erläutert, welche Feldstärken in verschieden großen Feldvariablen Kammern beim Einspeisen einer bestimmten hochfrequenten Leistung erreicht werden können. Anhand dieser Ergebnisse wird aufgezeigt, oberhalb welcher Grenzfrequenz eine Anwendung von FVKn nur sinnvoll erscheint. Mode-stirred chambers (MSCs can be used for radiated immunity tests in EMC testing. Advantageous compared to conventional test methods is the high field strength which can here be generated with less RF-Power. This point is often the main argument for pushing the standardization of MSCs as an other EMC testing environment. Especially for safety-critical electronic equipment like avionic or

  17. Investigation of correction factors for non-reference conditions in ion chamber photon dosimetry with Monte-Carlo simulations

    Energy Technology Data Exchange (ETDEWEB)

    Wulff, Joerg [Klinik fuer Strahlendiagnostik, Medizinisches Zentrum fuer Radiologie, Philipps Univ. Marburg (Germany); Inst. fuer Medizinische Physik und Strahlenschutz (IMPS), Fachhochschule Giessen-Friedberg (Germany); Heverhagen, Johannes T. [Klinik fuer Strahlendiagnostik, Medizinisches Zentrum fuer Radiologie, Philipps Univ. Marburg (Germany); Karle, Heiko [Klinik und Poliklinik fuer Radioonkologie sowie Strahlentherapie, Universitaetsmedizin der Johannes Gutenberg-Univ., Mainz (Germany); Zink, Klemens [Inst. fuer Medizinische Physik und Strahlenschutz (IMPS), Fachhochschule Giessen-Friedberg (Germany)

    2010-07-01

    Current dosimetry protocols require geometrical reference conditions for the determination of absorbed dose in external radiotherapy. Whenever these geometrical conditions cannot be maintained the application of additional corrections becomes necessary, in principle. The current DIN6800-2 protocol includes a corresponding factor k{sub NR}, but numerical values are lacking and no definite information about the magnitude of this correction is available yet. This study presents Monte-Carlo based calculations within the 6 MV-X photon field of a linear accelerator for a common used ion chamber (PTW31010) employing the EGSnrc code system. The linear accelerator model was matched to measurements, showing good agreement and is used as a realistic source. The individual perturbation correction factors as well as the resulting correction factor k{sub NR} were calculated as a function of depth for three field sizes, as a function of central axis distance for the largest field and within the build-up region. The behaviour of the ion chamber was further investigated for an idealized hypothetical field boundary. Within the field of the linear accelerator where charged particle equilibrium is achieved the factor k{sub NR} was generally below {proportional_to}0.5%. In the build-up region a depth dependent correction of up to 2% was calculated when positioning the chamber according to DIN6800-2. Minimizing the depth dependence of the corrections in the build-up region lead to a slightly different positioning of the ion chamber as currently recommended. In regions of the hypothetical field boundary with missing charged particle equilibrium and high dose gradients, the ion chamber response changed by up to {proportional_to}40%, caused by the comparatively large volume (0.125 cm{sup 3}) of the investigated chamber. (orig.)

  18. A new plant chamber facility PLUS coupled to the atmospheric simulation chamber SAPHIR

    Science.gov (United States)

    Hohaus, T.; Kuhn, U.; Andres, S.; Kaminski, M.; Rohrer, F.; Tillmann, R.; Wahner, A.; Wegener, R.; Yu, Z.; Kiendler-Scharr, A.

    2015-11-01

    A new PLant chamber Unit for Simulation (PLUS) for use with the atmosphere simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) has been build and characterized at the Forschungszentrum Jülich GmbH, Germany. The PLUS chamber is an environmentally controlled flow through plant chamber. Inside PLUS the natural blend of biogenic emissions of trees are mixed with synthetic air and are transferred to the SAPHIR chamber where the atmospheric chemistry and the impact of biogenic volatile organic compounds (BVOC) can be studied in detail. In PLUS all important enviromental parameters (e.g. temperature, PAR, soil RH etc.) are well-controlled. The gas exchange volume of 9.32 m3 which encloses the stem and the leafes of the plants is constructed such that gases are exposed to FEP Teflon film and other Teflon surfaces only to minimize any potential losses of BVOCs in the chamber. Solar radiation is simulated using 15 LED panels which have an emission strength up to 800 μmol m-2 s-1. Results of the initial characterization experiments are presented in detail. Background concentrations, mixing inside the gas exchange volume, and transfer rate of volatile organic compounds (VOC) through PLUS under different humidity conditions are explored. Typical plant characteristics such as light and temperature dependent BVOC emissions are studied using six Quercus Ilex trees and compared to previous studies. Results of an initial ozonolysis experiment of BVOC emissions from Quercus Ilex at typical atmospheric concentrations inside SAPHIR are presented to demonstrate a typical experimental set up and the utility of the newly added plant chamber.

  19. A new plant chamber facility, PLUS, coupled to the atmosphere simulation chamber SAPHIR

    Science.gov (United States)

    Hohaus, T.; Kuhn, U.; Andres, S.; Kaminski, M.; Rohrer, F.; Tillmann, R.; Wahner, A.; Wegener, R.; Yu, Z.; Kiendler-Scharr, A.

    2016-03-01

    A new PLant chamber Unit for Simulation (PLUS) for use with the atmosphere simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) has been built and characterized at the Forschungszentrum Jülich GmbH, Germany. The PLUS chamber is an environmentally controlled flow-through plant chamber. Inside PLUS the natural blend of biogenic emissions of trees is mixed with synthetic air and transferred to the SAPHIR chamber, where the atmospheric chemistry and the impact of biogenic volatile organic compounds (BVOCs) can be studied in detail. In PLUS all important environmental parameters (e.g., temperature, photosynthetically active radiation (PAR), soil relative humidity (RH)) are well controlled. The gas exchange volume of 9.32 m3 which encloses the stem and the leaves of the plants is constructed such that gases are exposed to only fluorinated ethylene propylene (FEP) Teflon film and other Teflon surfaces to minimize any potential losses of BVOCs in the chamber. Solar radiation is simulated using 15 light-emitting diode (LED) panels, which have an emission strength up to 800 µmol m-2 s-1. Results of the initial characterization experiments are presented in detail. Background concentrations, mixing inside the gas exchange volume, and transfer rate of volatile organic compounds (VOCs) through PLUS under different humidity conditions are explored. Typical plant characteristics such as light- and temperature- dependent BVOC emissions are studied using six Quercus ilex trees and compared to previous studies. Results of an initial ozonolysis experiment of BVOC emissions from Quercus ilex at typical atmospheric concentrations inside SAPHIR are presented to demonstrate a typical experimental setup and the utility of the newly added plant chamber.

  20. Conductive heat transfer from an isothermal magma chamber and its application to the measured heat flow distribution from mount hood, Oregon

    Science.gov (United States)

    Nathenson, Menuel; Tilling, Robert I.; ,

    1993-01-01

    A steady-state solution for heat transfer from an isothermal, spherical magma chamber, with an imposed regional geothermal gradient far from the chamber, is developed. The extensive published heat-flow data set for Mount Hood, Oregon, is dominated by conductive heat transfer in the deeper parts of most drill holes and provides an ideal application of such a model. Magma-chamber volumes or depths needed to match the distribution of heat-flow data are larger or shallower than those inferred from geologic evidence.