Corneal Thickness and Volume Measurements by Swept Source Anterior Segment Optical Coherence Tomography in Normal Subjects

2013 ◽  
Vol 38 (5) ◽  
pp. 531-536 ◽  
Author(s):  
Reina Fukuda ◽  
Tomohiko Usui ◽  
Takashi Miyai ◽  
Yosai Mori ◽  
Kazunori Miyata ◽  
...  
2021 ◽  
Vol 10 (5) ◽  
pp. 1094
Author(s):  
Michał Dembski ◽  
Anna Nowińska ◽  
Klaudia Ulfik-Dembska ◽  
Edward Wylęgała

Background: The present study determined the mean reference values of the anterior segment parameters of the selected eye using swept source optical coherence tomography (SS-OCT) in healthy Caucasian participants. Methods: A total of 166 volunteers (age 54–79 years), women (n = 92) and men (n = 74), were analyzed. One eye of each subject was randomly selected for anterior segment imaging. The anterior segment of the eye was scanned with CASIA2. The analyzed anterior segment parameters were divided into three groups, namely parameters of the cornea, lens, and angle. Results: The OCT (e.g., Ks, Kf, pKf, pKs, and central corneal thickness) and Fourier parameters of the cornea were significantly different between females and males. The iridocorneal angle was the smallest in the upper quadrant for all distance from the apex of the angle (250, 500, and 750 µm). Conclusions: Therefore, SS-OCT enables the analysis of parameters of the cornea, anterior chamber, lens, and iridocorneal angle, highlighting its clinical utility. Sex-specific differences in the analyzed parameters should be taken into account during the diagnosis of corneal diseases. The configuration of the filtration angle is an important marker during glaucoma diagnosis and drainage implant surgery. Measurements with CASIA 2is characterized by very good repeatability.


2012 ◽  
Vol 90 (6) ◽  
pp. e452-e457 ◽  
Author(s):  
Alberto Neri ◽  
Marianna Malori ◽  
Patrizia Scaroni ◽  
Rosachiara Leaci ◽  
Elisabetta Delfini ◽  
...  

2018 ◽  
Vol 16 (2) ◽  
pp. 86-94
Author(s):  
Vijaya Anandan ◽  
Rekha Srinivasan ◽  
Rashima Asokan ◽  
Ronnie George

Aim: To compare the anterior chamber volume measurements obtained with Pentacam and derived from anterior segment optical coherence tomography. Design: Cross-sectional study. Methods: We included normal subjects who underwent a comprehensive eye examination including refraction, keratometry, Goldmann applanation tonometry, gonioscopy, anterior segment optical coherence tomography (AS-OCT) (Carl Zeiss Meditec Inc.; Dublin, CA, USA) and Pentacam (Oculus Inc.; Lynnwood, WA, USA). Fifty scans were selected for Pentacam and 12 images were selected for calculation of anterior chamber volume. Only the right eye was considered for analysis. Results: One-hundred and nineteen eyes of 119 subjects were included for analysis. The mean age of the subjects was 42.58 ± 13.15 years, of which 74 were female and 45 were male. The mean anterior chamber volume measured using AS-OCT was 119.17 ± 26.56 mm3 and with Pentacam was 131.29 ± 34.26 mm3. The comparison of means between the two modalities was statistically significant (t = -8.857, Mean Difference (MD) = 12.11, 95% CI: (4.29, 19.95), p = 0.003). Bland-Altman plot showed poor agreement between the chamber volume measurements obtained by Pentacam and AS-OCT with MD of 12.1 mm3 (95 % CI: 41.4 to -17.1) and intra-class correlation between the two instruments was 0.94 (95% CI: 0.91, 0.96) (p < 0.0001). Conclusion: The anterior chamber volume can be measured using Pentacam as well as AS-OCT since these measurements were reliable. However, these measurements were not interchangeable due to poor levels of agreement.


2021 ◽  
pp. bjophthalmol-2020-318334
Author(s):  
Wei Wang ◽  
Jiaqing Zhang ◽  
Xiaoxun Gu ◽  
Xiaoting Ruan ◽  
Xiaoyun Chen ◽  
...  

Background/aimsThe primary objective is to quantify the lens nuclear opacity using swept-source anterior segment optical coherence tomography (SS-ASOCT) and to evaluate its correlations with Lens Opacities Classification System III (LOCS-III) system and surgical parameters. The secondary objective is to assess the diagnostic performance for hard nuclear cataract.MethodsThis cross-sectional study included 1222 patients eligible for cataract surgery (1222 eyes). The latest SS-ASOCT (CASIA-2) was used to obtain high-resolution lens images, and the average nuclear density (AND) and maximum nuclear density (MND) were measured by a custom ImageJ software. Spearman’s correlations analysis was used to assess associations of AND/MND with LOCS-III nuclear scores, visual acuity and surgical parameters. The subjects were then split randomly (9:1) into the training dataset and validating dataset. Receiver operating characteristic curves and calibration curves were constructed for the classification on hard nuclear cataract.ResultsThe AND and MND from SS-ASOCT images were significantly correlated with nuclear colour scores (AND: r=0.716; MND: r=0.660; p<0.001) and nuclear opalescence scores (AND: r=0.712; MND: r=0.655; p<0.001). The AND by SS-ASOCT images had the highest values of Spearman’s r for preoperative corrected distance visual acuity (r=0.3131), total ultrasonic time (r=0.3481) and cumulative dissipated energy (r=0.4265). The nuclear density had good performance in classifying hard nuclear cataract, with area under the curves of 0.859 (0.831–0.886) for AND and 0.796 (0.768–0.823) for MND.ConclusionObjective and quantitative evaluation of the lens nuclear density using SS-ASOCT images enable accurate diagnosis of hard nuclear cataract.


Cornea ◽  
2019 ◽  
Vol 38 (1) ◽  
pp. 93-97 ◽  
Author(s):  
Khaled Abdelazeem ◽  
Mohamed Sharaf ◽  
Mohamed G. A. Saleh ◽  
Ahmed M. Fathalla ◽  
Wael Soliman

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Riham S. H. M. Allam ◽  
Rania A. Ahmed

Purpose. To study features of the lower punctum in normal subjects using spectral domain anterior segment optical coherence tomography (SD AS-OCT).Methods. Observational cross-sectional study that included 147 punctae (76 subjects). Punctae were evaluated clinically for appearance, position, and size. AS-OCT was used to evaluate the punctal shape, contents, and junction with the vertical canaliculus. Inner and outer diameters as well as depth were measured.Results. 24 males and 52 females (mean age44±14.35 y) were included. Lower punctum was perceived by OCT to be an area with an outer diameter (mean412.16±163 μm), inner diameter (mean233.67±138.73 μm), and depth (mean251.7±126.58 μm). The OCT measured outer punctum diameter was significantly less than that measured clinically (P: 0.000). Seven major shapes were identified. The junction with the vertical canaliculus was detectable in 44%. Fluid was detected in 34%, one of which had an air bubble; however, 63% of punctae showed no contents and 4% had debris.Conclusions. AS-OCT can be a useful tool in understanding the anatomy of the punctum and distal lacrimal system as well as tear drainage physiology. Measuring the punctum size may play a role in plugs fitting.


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