Comparison of a new anterior segment optical coherence tomography and Oculus Pentacam for measurement of anterior chamber depth and corneal thickness

Purpose To determine the prevalence of trabecular-iris contact (TIC) and quantify this contact in healthy Caucasian individuals using Fourier-domain optical coherence tomography (FD-OCT). Methods For this cross-sectional study, 2,012 eyes of 1,006 healthy subjects were recruited among individuals undergoing a routine ophthalmologic checkup. In each participant, age, sex, intraocular pressure, and spherical refractive error were first recorded along with anterior chamber depth and volume, central corneal thickness measured with the Pentacam, and axial length with the IOLMaster. Anterior chamber angle variables and the presence of TIC in the horizontal quadrants were determined by anterior segment FD-OCT (RTVue 100®). When TIC was observed, TIC length (TICL) and its percentage in relation to the length of the trabecular meshwork (TICL percentage) were also measured. Results Trabecular-iris contact in the horizontal quadrants was observed in 34 eyes of 25 patients, representing 1.6% of the total number of eyes examined. In this subgroup of individuals, mean age was 55.8 years, 84% were women, and spherical refractive error ranged from -0.25 to 8.25 D. Eyes with TIC showed an angle width of less than 23.2 degrees and axial length shorter than 23.7 mm. Mean TICL was 239 ± 79 μm (103-495 μm) and mean TICL percentage was 46.9% ± 13.9% (17.2%-76.3%). Conclusions The prevalence of TIC was low in this population. Fourier-domain optical coherence tomography emerged as useful to assess its prevalence and quantify the extent of TIC.

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Assessment of Anterior Chamber by Ultrasound Biomicroscopy and Anterior Segment Optical Coherence Tomography in Patients with Inflammatory Glaucoma

Journal of International Medical Research ◽

10.1177/0300060519867808 ◽

2019 ◽

Vol 47 (12) ◽

pp. 5950-5956 ◽

Cited By ~ 1

Author(s):

Yiyong Qian ◽

Lin Liu ◽

Yuehui Shi ◽

Minli Wang ◽

Min Li ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Ciliary Body ◽

Imaging Techniques ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Ultrasound Biomicroscopy ◽

Optical Coherence ◽

Pars Plana

Objective To investigate the clinical indications of ultrasound biomicroscopy (UBM) and anterior segment optical coherence tomography (AS-OCT) in eyes with inflammatory glaucoma. Methods Sixteen patients (16 eyes) with inflammatory glaucoma were analysed retrospectively. All of the subjects underwent UBM and AS-OCT scans, measuring the following parameters: central corneal thickness (CCT), central anterior chamber depth (ACD), angle-opening distance (AOD500), and trabecular-iris angle (TIA500) in four quadrants. Results Both the UBM and AS-OCT generated detailed, high-resolution images of the anterior segments of the eyes with inflammatory glaucoma. Moreover, the UBM and AS-OCT exhibited statistically similar measurement results for all of the indices. A Bland–Altman analysis showed a high level of agreement between the two imaging techniques. Additionally, the UBM was able to visualize the ciliary body and pars plana, while the cells and the flare in the anterior chamber appeared more pronounced in the UBM images. Conclusions Both the UBM and AS-OCT are useful tools for anterior segment imaging and taking measurements needed for evaluating inflammatory glaucoma. The AS-OCT has the advantages of being noninvasive and fast, whereas the UBM is presently unparalleled in the visualization of the ciliary body and pars plana.

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Agreement between anterior segment Optical Coherence Tomography, Lenstar and Ultrasound Biomicroscopy measurements of anterior segment parameters

10.21203/rs.2.427/v1 ◽

2019 ◽

Author(s):

Ziyan Yu ◽

Ting Huang ◽

Qiao Yu ◽

Jun Kong ◽

Bo Qu

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Ultrasound Biomicroscopy ◽

Optical Coherence ◽

Significant Difference ◽

Medical University

Abstract Purpose To compare anterior chamber depth (ACD) and central corneal thickness (CCT) measurements by anterior segment optical coherence tomography (AS-OCT), Lenstar and ultrasound biomicroscopy (UBM). Methods A retrospective cross section study. A total of 83 eyes from 54 patients were included. Central corneal thickness (CCT) and anterior chamber depth (ACD) values obtained from three devices (AS-OCT, Lenstar and UBM) were recorded. All patients were collected from Oct. 2015 to Aug. 2016 in the Fourth Affiliated Hospital of China Medical University. Differences of these three devices (ACD and CCT) were statistically analyzed by randomized blocks analysis. Pearson correlative analysis and Bland-Altman analysis were used to compare the correlation and agreement. Results There’s no significant difference in measuring ACD by Lenstar and UBM (P>0.05), but there were significant differences in other two groups (AS-OCT and UBM, AS-OCT and Lenstar) (P<0.05). There were significant differences in the mean CCT measured by the three devices (P<0.05). There were high correlation in measuring ACD (all P<0.001, r1=0.928,r2=0.982,r3=0.932, respectively), and CCT(all P<0.001,r1=0.957,r2=0.949,r3=0.928, respectively). Conclusion AS-OCT, Lenstar and UBM yielded comparable results and are all can be used interchangeably for anterior segment measurements.

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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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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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Risk factors and evaluation of keratoconus progression after penetrating keratoplasty with anterior segment optical coherence tomography

Scientific Reports ◽

10.1038/s41598-020-75412-y ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Junko Yoshida ◽

Tetsuya Toyono ◽

Rika Shirakawa ◽

Takashi Miyai ◽

Tomohiko Usui

Keyword(s):

Risk Factors ◽

Optical Coherence Tomography ◽

Penetrating Keratoplasty ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Optical Coherence ◽

Graft Size ◽

Corneal Power ◽

Corneal Thinning

Abstract To determine the risk factors and unique characteristics of keratoconus (KC) progression after penetrating keratoplasty (PK), anterior segment optical coherence tomography parameters were statistically analyzed in comparison with eyes undergoing PK for other diseases as a control. Ninety-one eyes maintaining clear PK grafts for over 10 years were divided into 2 groups according to the primary indication for PK (KC vs Others groups). Corneal thinning indicators (inferior host thinnest corneal thickness/central corneal thickness [IHT/CCT], inferior graft thinnest corneal thickness/CCT [IGT/CCT]), were smaller whereas anterior chamber depth, and steepest corneal power (Ks), and maximum corneal power (Kmax) were larger in the KC group with statistical significance. Graft size, Kmax and Ks correlated with IHT/CCT and IGT/CCT in the KC group. These correlations were not detected in controls. Graft size and postoperative period were selected by multivariate regression analysis as factors for corneal ectatic changes in the KC group. In conclusion, KC eyes long after PK show inferior graft and host corneal thinning, and corneal protrusion. Corneal power parameters such as Kmax or Ks can be used to monitor KC progression after PK. A small graft might lead to KC progression after PK.

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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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