Effects of 0.01% Atropine Instillation Assessed Using Swept-Source Anterior Segment Optical Coherence Tomography

In this paper, we assessed the short-term effects of 0.01% atropine eye drops on anterior segment parameters by performing ocular biometry using a swept-source anterior segment optical coherence tomography system (AS-OCT). We recruited 17 healthy volunteers (10 men and 7 women aged 24–35 years) with no history of eye disease. Participants without accommodative demand demonstrated significant mydriasis 1 h after the atropine instillation (4.58 ± 0.77 to 5.41 ± 0.83 mm). Pupil diameters with a 5 diopter (D) accommodative stimulus at 1 h (4.70 ± 1.13 mm) and 24 h (4.05 ± 1.06 mm) after atropine instillation were significantly larger than those at baseline (3.71 ± 0.84 mm). Barring pupil diameter, no other biometric parameters significantly changed at any point in time after atropine instillation without accommodative demand. However, with an accommodative stimulus, anterior chamber depth (ACD) at 1 h and posterior curvature of the lens at 1 and 24 h were both significantly larger than those before atropine instillation. Using AS-OCT, we detected a slight decrease in the accommodation response of ocular biometric components evoked by 0.01% atropine instillation. Morphologically, our measurements suggested a change in the ACD and horizontal radius of the lens’ posterior surface curvatures due to the subtle reduction of accommodation.

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Assessment of anterior chamber configuration changes after phacoemulsification with swept-source optical coherence tomography

10.21203/rs.2.9863/v1 ◽

2019 ◽

Author(s):

Man Hu ◽

Qian Zheng ◽

Zhangliang Li ◽

Pingjun Chang ◽

Yun-e Zhao

Keyword(s):

Optical Coherence Tomography ◽

Cataract Surgery ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Optical Coherence ◽

Swept Source ◽

Narrow Angle ◽

Age Related ◽

Shallow Anterior Chamber

Abstract Background To assess the changes of anterior chamber angle in patients with shallow anterior chamber and normal anterior chamber after phacoemulsification and intraocular lens implantation (IOL) using anterior segment swept-source optical coherence tomography (AS-SS-OCT). Methods This was a prospective case control study; 60 eyes of 60 patients who underwent cataract surgery. Based on anterior chamber depth (ACD) and gonioscopy findings, the eyes were classified into two groups, shallow anterior chamber group (30 eyes) and normal anterior chamber group (30 eyes). AS-SS-OCT was used to measure ACD and angle parameters angle opening distance (AOD), angle recess area (ARA), trabecular iris space area(TISA), and trabecular iris angle (TIA). Serial changes in each group were measured before and 3 months after phacoemulsification and IOL, and the differences between the two groups were compared. Results All angle parameters including ACD, AOD, ARA, TISA, and TIA in both groups at 3 months after cataract surgery were significantly different from the preoperative values (p<0.01). In addition, we found significant differences of all angle parameters between groups of shallow anterior chamber (SAC) and normal anterior chamber (NAC) (All P< 0.05). Besides, the TISA750 in superior quadrant and anterior chamber volume (ACV) were significantly smaller in the group of SAC than those in the group of NAC (P = 0.041 and 0.002, respectively). Conclusions The parameters of anterior chamber increased significantly in both two groups but not increase to the same extent 3 months after phacoemulsification. Iris thickening may also be one of the narrow angle factors,not just age-related lens thickening.

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Anterior chamber angle imaging with swept-source optical coherence tomography: comparison between CASIAII and ANTERION

Scientific Reports ◽

10.1038/s41598-020-74813-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Poemen Pui-man Chan ◽

Gilda Lai ◽

Vivian Chiu ◽

Anita Chong ◽

Marco Yu ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Angle Closure ◽

Optical Coherence ◽

Anterior Chamber Angle ◽

Swept Source ◽

Scan Pattern ◽

Chamber Angle

Abstract This study compared the test–retest variabilities and measurement agreement of anterior chamber angle (ACA) dimensions measured by two anterior segment swept-source optical coherence tomography (SS-OCT)—the ANTERION (Heidelberg Engineering, Heidelberg, Germany) and CASIAII (Tomey, Nagoya, Japan). Thirty-eight subjects, 18 patients with primary angle closure and 20 healthy participants with open angles, were included. The mean age was 54.7 ± 15.8 years (range: 26–75 years). One eye of each subject was randomly selected for anterior segment imaging by ANTERION and CASIAII, using the same scan pattern (6 evenly spaced radial scans across the anterior segment for three times) in the same visit. The between- and within-instrument agreement and repeatability coefficients of angle open distance (AOD500), trabecular-iris space area (TISA500), lens vault (LV), scleral spur-scleral spur distance (SSD), anterior chamber depth (ACD), and pupil diameter (PD) were measured. The anterior and posterior boundaries of the cornea, iris, and lens were automatically segmented by the SS-OCT instruments; the scleral spur was manually located by a single masked observer. There were significant differences between ANTERION and CASIAII measurements; the SSD, PD, and ACD were smaller whereas AOD500 and TISA500 were greater in ANTERION compared with CASIAII (P < 0.001). Anterior segment measurements obtained from the two SS-OCT instruments showed strong associations (R2 ranged between 0.866 and 0.998) although the between-instrument agreement was poor; the spans of 95% limits of between-instrument agreement were ≥ 1.5-folds than the within-instrument agreement for either instrument. Whereas both SS-OCT instruments showed low test–retest measurement variabilities, the repeatability coefficients of AOD500, TISA500, ACD, and PD were slightly smaller for CASIAII than ANTERION (P ≤ 0.012).

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Understanding diagnostic disagreement in angle closure assessment between anterior segment optical coherence tomography and gonioscopy

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2019-314672 ◽

2019 ◽

Vol 104 (6) ◽

pp. 795-799 ◽

Cited By ~ 4

Author(s):

Natalia Porporato ◽

Mani Baskaran ◽

Tin A Tun ◽

Rehena Sultana ◽

Marcus Tan ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Cross Sectional Study ◽

False Positives ◽

Angle Closure ◽

Optical Coherence ◽

Cross Sectional ◽

Swept Source

Background/aimsAlthough being a more objective tool for assessment and follow-up of angle closure, reliability studies have reported a moderate diagnostic performance for anterior segment optical coherence tomography (OCT) technologies when comparing with gonioscopy as the reference standard. We aim to determine factors associated with diagnostic disagreement in angle closure when assessed by anterior segment swept source OCT (SS-OCT, CASIA SS-1000; Tomey, Nagoya, Japan) and gonioscopy.MethodsCross-sectional study. A total of 2027 phakic subjects aged ≥50 years, with no relevant previous ophthalmic history, were consecutively recruited from a community polyclinic in Singapore. Gonioscopy and SS-OCT (128 radial scans) for the entire circumference of the angle were performed for each subject. A two-quadrant closed gonioscopic definition was used. On SS-OCT images, angle closure was defined as iridotrabecular contact (ITC) to the extent of ≥35%, ≥50% and ≥75% of the circumferential angle. Diagnostic disagreements between both methods, that is, false positives or overcalls and false negatives or undercalls were defined, respectively, as gonioscopic open/closed angles inversely assessed as closed/open by SS-OCT.ResultsTwo hundred and seventy-two (14.7%) resulted in overcall results (false positives) when ≥50% of the angle circumference was closed using SS-OCT. These eyes had significantly wider (anterior chamber width, 11.7 vs 11.6 mm, p<0.001) and deeper (anterior chamber depth (ACD), 2.4 vs 2.2 mm, p<0.001) anterior chambers than eyes assessed by both methods as closed (true positives). Deeper ACD (OR 9.31) and lower lens vault (LV) (OR 0.04) were significantly associated with a false positive diagnosis in the multivariate analysis. Most of these cases had short (52.6%) or irregular (39%) ITC in SS-OCT images.ConclusionsWe found that anterior chamber dimensions, determined by ACD and LV, were factors significantly associated with diagnostic disagreement between anterior segment SS-OCT and gonioscopy in angle closure assessment.

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Short-term Dynamics after Single- and Three-piece Acrylic Intraocular Lens Implantation: A Swept-source Anterior Segment Optical Coherence Tomography Study

Scientific Reports ◽

10.1038/s41598-018-28609-1 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 6

Author(s):

Tatsuhiko Sato ◽

Shunsuke Shibata ◽

Motoaki Yoshida ◽

Ken Hayashi

Keyword(s):

Optical Coherence Tomography ◽

Intraocular Lens ◽

Anterior Segment ◽

Optical Coherence ◽

Intraocular Lens Implantation ◽

Short Term ◽

Swept Source ◽

Lens Implantation

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Changes in anterior segment optical coherence tomography following pars plana vitrectomy without tamponade

International Journal of Retina and Vitreous ◽

10.1186/s40942-021-00285-w ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Alireza Khodabande ◽

Massood Mohammadi ◽

Hamid Riazi-Esfahani ◽

Shahab Karami ◽

Massood Mirghorbani ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Pars Plana Vitrectomy ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Optical Coherence ◽

Mean Values ◽

Iop Measurement ◽

Pars Plana ◽

The Mean

Abstract Background To evaluate changes in anterior segment morphology on anterior segment optical coherence tomography (AS-OCT) following pars plana vitrectomy (PPV) without tamponade. Methods Patients who underwent PPV without tamponade for epiretinal membrane were evaluated. Eligible patients underwent intraocular pressure (IOP) measurement and AS-OCT preoperatively as well as 1 month and 6 months post-operatively. Anterior chamber width (ACW), anterior chamber depth (ACD), trabecular iris angle (TIA), angle opening distance at 500 and 750 µm (AOD), and trabecular iris space area at 500 and 750 µm (TISA) at four quadrants were recorded and analyzed. Additionally, the mean values of TIA (MTIA), AOD (MAOD), and TISA (MTISA) for each eye (mean of four quadrants) were analyzed. Results 23 patients completed the study. The mean age of participants was 56.4 ± 3.6 years of age and 13/23 (56%) were female. Mean IOP of patients was 18.1 ± 1.1, 18.3 ± 1.1, and 18.1 ± 1.2 preoperatively,1 month post-operatively, and 6 months post-operatively, respectively. (p = 0.83). No difference was detected post-operatively in measurements of ACW, ACD, MTIA, MAOD500, MAOD750, MTISA500, and MTISA750. Conclusion Pars plana vitrectomy without tamponade was not associated with changes in anterior chamber morphology.

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Comparison of anterior ocular biometry between optical low-coherence reflectometry and anterior segment optical coherence tomography in an adult Chinese population

Journal of Cataract & Refractive Surgery ◽

10.1016/j.jcrs.2011.12.031 ◽

2012 ◽

Vol 38 (6) ◽

pp. 966-970 ◽

Cited By ~ 5

Author(s):

Peiyang Shen ◽

Xiaohu Ding ◽

Nathan G. Congdon ◽

Yingfeng Zheng ◽

Mingguang He

Keyword(s):

Optical Coherence Tomography ◽

Chinese Population ◽

Anterior Segment ◽

Optical Coherence ◽

Low Coherence ◽

Ocular Biometry ◽

Optical Low Coherence Reflectometry

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Objective quantification of lens nuclear opacities using swept-source anterior segment optical coherence tomography

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2020-318334 ◽

2021 ◽

pp. bjophthalmol-2020-318334

Author(s):

Wei Wang ◽

Jiaqing Zhang ◽

Xiaoxun Gu ◽

Xiaoting Ruan ◽

Xiaoyun Chen ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Visual Acuity ◽

Anterior Segment ◽

Training Dataset ◽

Dissipated Energy ◽

Nuclear Density ◽

Optical Coherence ◽

Nuclear Cataract ◽

Swept Source ◽

Ultrasonic Time

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.

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