Search

Aim: To investigate the corneal epithelial and limbal epithelial alterations in patients under topical glaucoma treatment using anterior segment-OCT (AS-OCT) and to determine the changes of the limbal region due to the preservatives and glaucoma drugs, that can progress to limbal stem cell deficiency (LSCD). Limbal thickness was measured by AS-OCT to evaluate limbal cell deficiency., Methods: Forty-seven patients using topical medication for glaucoma, and 48 control subjects were enrolled in this matched case-control study. The patients were divided into four groups according to the treatment regimens. Group 1: One-drug regimen, Group 2: Two-drug regimen, Group 3: Three-drug regimen, Group 4: Four-drug regimen For the ocular surface evaluation; tear break-up time with standard fluorescein sodium sterile strip application, Schirmer test-I, Ocular Surface Disease Index Questionnaire, and AS-OCT were performed., Results: A total of 95 subjects were included: 47 eyes of 47 patients with glaucoma medication and 48 eyes of 48 healthy subjects. There was a statistically significant difference between patients and controls according to BUT, SCH, and OSDI ( p  < 0.001). The mean central corneal epithelium thickness was 48.5 ± 5.3 in patients and 54.5 ± 5.9 in controls ( p  < 0.001). The mean central total corneal thickness was 529.2 ± 41.2 in patients and 536 ± 35.3 in controls ( p  = 0.335). The mean limbal epithelium thickness was 64.1 ± 9.1 in patients and 76 ± 11.5 in controls ( p  < 0.001)., Conclusion: Using at least one glaucoma drug caused limbal area injury, changed ocular surface measurements, and significantly reduced the limbal epithelial thickness where the stem cells reside. The limbal epithelial thickness measurement by AS-OCT seems to be an innovative, non-invasive, and promising technique for detecting and staging corneal damage in topical glaucoma therapy.

Background: The object of this study is to investigate the effect of early bleb parameters measured by three-dimensional anterior-segment optical coherence tomography on the surgical success of trabeculectomy., Methods: This retrospective study included 45 patients with 19 of exfoliation glaucoma, 17 of primary open angle glaucoma, 4 of neovascular glaucoma, 4 of uveitic glaucoma and 1 of glaucoma caused from familial amyloid polyneuropathy who underwent trabeculectomy. Bleb parameters, such as total bleb height, the position and the width of filtration openings on the scleral flap, bleb wall thickness, fluid-filled cavity height, and bleb wall intensity were assessed by three-dimensional anterior-segment optical coherence tomography 0.5 months after trabeculectomy, and were subjected to a Cox proportional hazard model as potential prognostic factors. Surgical success was defined as: IOP < 21 mmHg (A), < 18 mmHg (B), < 15 mmHg (C) with (qualified success) or without medication (complete success). Complete failure was defined as hypotony and additional glaucoma surgeries required., Results: The width of filtration openings was identified as a prognostic factor for all criteria. By multivariable analysis, the width of the filtration openings was a prognostic factor in all criteria tested, and the preoperative IOP were significant prognostic factors for surgical success in qualified success in criteria B and C. Separate from the median widths of filtration openings, wide filtration opening showed significant survival ratio for qualified success in criteria A and B and for complete success in all criteria, respectively., Conclusions: The width of filtration opening at an early stage is a prognostic factor for surgical success of trabeculectomy.

Purpose: The purpose of this study was to use Triton® SweptSource OCT to evaluate the morphology of blebs formed when eyes are treated with XEN® implants and to compare these with the blebs in successfully functioning eyes after trabeculectomy (TB) and with eyes of healthy controls., Methods: A cross-sectional, observational study. We analyzed 25 eyes, 15 after TB and 10 with XEN® implants, comparing them with 23 healthy eyes (controls). We evaluated the conjunctival morphology of the eyes using AS-OCT. The main parameters evaluated were bleb height, sub-epithelial fibrosis, epithelial thickness, and changes in intraocular pressure (IOP)., Results: We found that the filtering blebs formed in eyes in which a XEN® stent was implanted were significantly flatter (bleb height 417 ± 183 μm) than the blebs formed in TB eyes (bleb height 618 ± 256 μm, p < 0.05). Moreover, sub-epithelial fibrosis did not develop in any of the blebs produced by the XEN stent, whereas some fibrosis was evident in 40% of the blebs that formed after TB (p < 0.05). The epithelium was thicker when the XEN implant was used (65 ± 18.5 μm) than when eyes underwent TB (60 ± 17.7 μm), and it was thicker than in control eyes (51 ± 9.7 μm, p < 0.05). Moreover, the decrease in the IOP induced by the XEN® stent (- 8.5 ± 5.3 mmHg) was similar to that produced by TB (- 8.8 ± 5.2 mmHg, p > 0.05)., Conclusions: Filtering blebs obtained after the introduction of a XEN® stent were morphologically distinct to those produced by TB, and they are more similar to the healthy conjunctiva.

Purpose: To compare the safety and efficacy of subconjunctival injection (MMC: 0.02%) to those with subconjunctival application of sponges soaked in Mitomycin C (MMC: 0.02%) intra-operatively in patients who underwent phacotrabeculectomy. Methods: A total of 68 patients undergoing phacotrabeculectomy were randomized into two groups; the sponge group received 0.02% MMC-soaked sponges (n = 38), and the injection group received subconjunctival injection of 0.02% MMC (n = 30). The primary outcome was post-operative mean intra-ocular pressure reduction (IOP). The secondary outcomes were bleb morphology using Indiana Bleb Appearance Grading Score (IBAGS) and anterior segment optical coherence tomography (AS-OCT), post-operative use of 5-fluorouracil, and complications rates. These were compared at 1 week and 1, 3, and 6 months post-operatively. Complete success was defined as ≥30% reduction in IOP without anti-glaucoma medications. Results: In sponge and injection groups, the mean pre-operative IOP was 29.1 ± 8.1 and 29.8 ± 8.8 mmHg, respectively. At 6 months, IOP in sponge and injection groups reduced by 52% (14 ± 3.6 mmHg, P < 0.001) and 50% (15.2 ± 4.1 mmHg, P < 0.001), respectively. Complete success was observed in 90.9% in the sponge group and 95.83% in the injection group. Both groups had diffuse, shallow, relatively avascular blebs at 6 months using IBAGS and AS-OCT. A few complications were seen in the sponge group during this period, which were not vision-threatening. Conclusion: Subconjunctival MMC injection is an effective, safe, convenient, and time-saving alternative to sponge-soaked delivery of MMC in phacotrabeculectomy. [ABSTRACT FROM AUTHOR]

Trabeculectomy has traditionally been upheld as the gold standard in glaucoma surgery, but recent advancements, including the PRESERFLO® MicroShunt, have introduced less invasive techniques to mitigate complications and reduce intraocular pressure (IOP). The examination of bleb morphology post-filtering surgery is critical for modulating wound healing and ensuring long-term success. While previous evaluations of PRESERFLO-generated blebs have relied on data from trabeculectomy blebs, the differing surgical techniques used in PRESERFLO and trabeculectomy surgeries suggest potential variations in bleb morphologies. This study conducted a comparative analysis of blebs resulting from PRESERFLO and trabeculectomy procedures. Retrospective descriptive assessments using the Jenaer Bleb Grading System were performed, along with quantitative evaluation using eight-dimensional parameters utilizing anterior segment OCT. We included 93 eyes (57 following PRESERFLO, 36 following trabeculectomy). In the descriptive assessment, PRESERFLO-generated blebs exhibited fewer conjunctival cysts (3.5% vs. 22.2%, p = 0.007) and cavernous changes (10.5% vs. 30.5%, p = 0.021) compared to trabeculectomy. Quantitatively, overall bleb dimensions were comparable (maximal bleb height, width, and length, p > 0.05 for all). However, PRESERFLO blebs displayed a shallower (0.52 ± 0.24 vs. 0.67 ± 0.3 mm, p = 0.017) yet longer (4.12 ± 1.54 vs. 3.23 ± 1.64 mm, p = 0.024) episcleral lake. A thicker bleb wall (1.52 ± 0.46 vs. 1.10 ± 0.37 mm, p < 0.001) along with more posteriorly positioned blebs (distance to limbus = 6.16 ± 1.36 vs. 4.87 ± 1.34 mm, p < 0.001) were observed following PRESERFLO. This study illuminates the nuanced morphological differences between PRESERFLO and trabeculectomy blebs. Understanding these distinctions is vital, empowering clinicians to make informed postoperative decisions and avoid misinterpretation of bleb morphology. [ABSTRACT FROM AUTHOR]

Background: Secondary angle closure glaucoma (SACG) can be quite puzzling and can challenge even an experienced glaucoma surgeon. Unlike primary angle closure glaucoma, SACG can have various ocular and systemic associations. A careful review of the symptoms and past ocular and surgical history cannot be overemphasized. Some of the SACG can be refractory, requiring drainage devices. However, sometimes, all it takes is a prompt laser iridotomy. This can significantly reduce ocular morbidity and, in some situations, even blindness. Gonioscopy, often an underutilized technique, is critical in making the right diagnosis. With the advent of imaging techniques such as anterior segment optical coherence tomography and ultrasound biomicroscopy, one can easily pick up the etiology and treat early. Purpose: As many cases of SACG present acutely, it is critical that one makes a prompt diagnosis. We present here a video bouquet of illustrated examples of SACG and the steps to identify the cause by using different imaging techniques. Through this video, we aim to make the diagnosis of SACG a simpler, more streamlined, and logical process that will help in the accurate diagnosis and management. Synopsis: This video demonstrates various etiologies of secondary angle closure and methods to identify and treat the same. Highlights: Secondary angle closure can occur either with or without pupillary block. SACG with pupillary block involves mechanisms such as seclusio pupillae, aphakic/pseudophakic glaucoma, phacomorphic glaucoma, and silicon oil-induced glaucoma. In contrast, there are various other etiologies causing anterior pulling or posterior pushing mechanisms that contribute to non-pupillary block SACG. We discuss all of these, along with the imaging modalities needed to identify the same. Video link: https://youtu.be/N0bIw7Uknww. [ABSTRACT FROM AUTHOR]

Aim: To evaluate a useful, non-contact method for the follow-up of pericardium patch graft changes in patients undergoing PAUL® Glaucoma Implant (PGI) surgery using high-resolution anterior segment optical coherence tomography (OCT) to predict tube erosions.Prospective analysis over six months of tube pericardium patch graft thickness of PGI surgical cases at the University Eye Hospital Bonn, Germany, from November 2021 to August 2022. In all eyes, Tutopatch® (RTI Surgical, United States) pericardium was used to cover the implant intra-operatively. Anterior segment OCT (AS-OCT, Heidelberg ANTERION® Swept-Source-OCT) examinations were performed following a standardized protocol to measure quantitative and qualitative aspects of the patch grafts before surgery, and at three and six months after surgery.Twenty-six eyes of 26 patients were included. Thickness of the patch material was 1188 µm (IQR 415 µm) directly after implantation and decreased over time to 1068 µm (IQR 478 µm) at 3 months and 846 µm (IQR 677 µm) at 6 months. No significant differences between groups were shown concerning gender (p = 0.128), ethnicity (p = 1.000), age (p = 0.741), glaucoma type (p = 0.173), other concurrent diseases (p = 0.302), former glaucoma surgeries (p = 1.000) and the quadrant of implantation (p = 0.555). Five eyes developed implant exposure. When comparing eyes with and without tube exposure, no significant differences were shown in average patch thickness above the tube directly after implantation (p = 0.476). However, significant differences in average thickness were observed at 3 months (p = 0.013) and 6 months (p = 0.005).Pericardial patch grafts tend to thin over time which can be assessed by AS-OCT, the latter proving to be a useful method to follow-up patients who undergo patch graft implantation during PGI surgery. This investigation could potentially help identify patients at risk of tube exposure which in turn could lead to modification of patient management. It could also possibly be used in future studies to find more suitable patch materials.Methods: To evaluate a useful, non-contact method for the follow-up of pericardium patch graft changes in patients undergoing PAUL® Glaucoma Implant (PGI) surgery using high-resolution anterior segment optical coherence tomography (OCT) to predict tube erosions.Prospective analysis over six months of tube pericardium patch graft thickness of PGI surgical cases at the University Eye Hospital Bonn, Germany, from November 2021 to August 2022. In all eyes, Tutopatch® (RTI Surgical, United States) pericardium was used to cover the implant intra-operatively. Anterior segment OCT (AS-OCT, Heidelberg ANTERION® Swept-Source-OCT) examinations were performed following a standardized protocol to measure quantitative and qualitative aspects of the patch grafts before surgery, and at three and six months after surgery.Twenty-six eyes of 26 patients were included. Thickness of the patch material was 1188 µm (IQR 415 µm) directly after implantation and decreased over time to 1068 µm (IQR 478 µm) at 3 months and 846 µm (IQR 677 µm) at 6 months. No significant differences between groups were shown concerning gender (p = 0.128), ethnicity (p = 1.000), age (p = 0.741), glaucoma type (p = 0.173), other concurrent diseases (p = 0.302), former glaucoma surgeries (p = 1.000) and the quadrant of implantation (p = 0.555). Five eyes developed implant exposure. When comparing eyes with and without tube exposure, no significant differences were shown in average patch thickness above the tube directly after implantation (p = 0.476). However, significant differences in average thickness were observed at 3 months (p = 0.013) and 6 months (p = 0.005).Pericardial patch grafts tend to thin over time which can be assessed by AS-OCT, the latter proving to be a useful method to follow-up patients who undergo patch graft implantation during PGI surgery. This investigation could potentially help identify patients at risk of tube exposure which in turn could lead to modification of patient management. It could also possibly be used in future studies to find more suitable patch materials.Results: To evaluate a useful, non-contact method for the follow-up of pericardium patch graft changes in patients undergoing PAUL® Glaucoma Implant (PGI) surgery using high-resolution anterior segment optical coherence tomography (OCT) to predict tube erosions.Prospective analysis over six months of tube pericardium patch graft thickness of PGI surgical cases at the University Eye Hospital Bonn, Germany, from November 2021 to August 2022. In all eyes, Tutopatch® (RTI Surgical, United States) pericardium was used to cover the implant intra-operatively. Anterior segment OCT (AS-OCT, Heidelberg ANTERION® Swept-Source-OCT) examinations were performed following a standardized protocol to measure quantitative and qualitative aspects of the patch grafts before surgery, and at three and six months after surgery.Twenty-six eyes of 26 patients were included. Thickness of the patch material was 1188 µm (IQR 415 µm) directly after implantation and decreased over time to 1068 µm (IQR 478 µm) at 3 months and 846 µm (IQR 677 µm) at 6 months. No significant differences between groups were shown concerning gender (p = 0.128), ethnicity (p = 1.000), age (p = 0.741), glaucoma type (p = 0.173), other concurrent diseases (p = 0.302), former glaucoma surgeries (p = 1.000) and the quadrant of implantation (p = 0.555). Five eyes developed implant exposure. When comparing eyes with and without tube exposure, no significant differences were shown in average patch thickness above the tube directly after implantation (p = 0.476). However, significant differences in average thickness were observed at 3 months (p = 0.013) and 6 months (p = 0.005).Pericardial patch grafts tend to thin over time which can be assessed by AS-OCT, the latter proving to be a useful method to follow-up patients who undergo patch graft implantation during PGI surgery. This investigation could potentially help identify patients at risk of tube exposure which in turn could lead to modification of patient management. It could also possibly be used in future studies to find more suitable patch materials.Conclusions: To evaluate a useful, non-contact method for the follow-up of pericardium patch graft changes in patients undergoing PAUL® Glaucoma Implant (PGI) surgery using high-resolution anterior segment optical coherence tomography (OCT) to predict tube erosions.Prospective analysis over six months of tube pericardium patch graft thickness of PGI surgical cases at the University Eye Hospital Bonn, Germany, from November 2021 to August 2022. In all eyes, Tutopatch® (RTI Surgical, United States) pericardium was used to cover the implant intra-operatively. Anterior segment OCT (AS-OCT, Heidelberg ANTERION® Swept-Source-OCT) examinations were performed following a standardized protocol to measure quantitative and qualitative aspects of the patch grafts before surgery, and at three and six months after surgery.Twenty-six eyes of 26 patients were included. Thickness of the patch material was 1188 µm (IQR 415 µm) directly after implantation and decreased over time to 1068 µm (IQR 478 µm) at 3 months and 846 µm (IQR 677 µm) at 6 months. No significant differences between groups were shown concerning gender (p = 0.128), ethnicity (p = 1.000), age (p = 0.741), glaucoma type (p = 0.173), other concurrent diseases (p = 0.302), former glaucoma surgeries (p = 1.000) and the quadrant of implantation (p = 0.555). Five eyes developed implant exposure. When comparing eyes with and without tube exposure, no significant differences were shown in average patch thickness above the tube directly after implantation (p = 0.476). However, significant differences in average thickness were observed at 3 months (p = 0.013) and 6 months (p = 0.005).Pericardial patch grafts tend to thin over time which can be assessed by AS-OCT, the latter proving to be a useful method to follow-up patients who undergo patch graft implantation during PGI surgery. This investigation could potentially help identify patients at risk of tube exposure which in turn could lead to modification of patient management. It could also possibly be used in future studies to find more suitable patch materials. [ABSTRACT FROM AUTHOR]

To assess baseline ocular biometric risk factors for progression from primary angle closure suspect (PACS) to primary angle closure (PAC) or acute angle closure (AAC). Prospective, observational study. Six hundred forty-three mainland Chinese with untreated PACS. Participants underwent baseline clinical examinations, including gonioscopy, anterior segment OCT (AS-OCT) imaging, and A-scan ultrasound biometry as part of the Zhongshan Angle Closure Prevention (ZAP) Trial. Primary angle closure suspect was defined as an inability to visualize pigmented trabecular meshwork in 2 or more quadrants based on static gonioscopy. Primary angle closure was defined as development of intraocular pressure above 24 mmHg or peripheral anterior synechiae. Progression was defined as development of PAC or an AAC attack. Multivariable logistic regression models were developed to assess biometric risk factors for progression. Six-year progression from PACS to PAC or AAC. Six hundred forty-three untreated eyes (609 nonprogressors, 34 progressors) of 643 participants were analyzed. In a multivariable model with continuous parameters, narrower horizontal angle opening distance of 500 μm from the scleral spur (AOD 500 ; odds ratio [OR], 1.10 per 0.01-mm decrease; P = 0.03), flatter horizontal iris curvature (IC; OR, 1.96 per 0.1-mm decrease; P = 0.01), and older age (OR, 1.11 per 1-year increase; P = 0.01) at baseline were associated significantly with progression (area under the receiver operating characteristic curve [AUC], 0.73). Smaller cumulative gonioscopy score was not associated with progression (OR, 1.03 per 1-modified Shaffer grade decrease; P = 0.85) when replacing horizontal AOD 500 in the multivariable model. In a separate multivariable model with categorical parameters, participants in the lowest quartile of horizontal AOD 500 (OR, 3.10; P = 0.002) and IC (OR, 2.48; P = 0.014) measurements and 59 years of age or older (OR, 2.68; P = 0.01) at baseline showed higher odds of progression (AUC, 0.72). Ocular biometric measurements can help to risk-stratify patients with early angle closure for more severe disease. Anterior segment OCT measurements of biometric parameters describing the angle and iris are predictive of progression from PACS to PAC or AAC, whereas gonioscopy grades are not. [ABSTRACT FROM AUTHOR]

To develop and evaluate the performance of a 3-dimensional (3D) deep-learning–based automated digital gonioscopy system (DGS) in detecting 2 major characteristics in eyes with suspected primary angle-closure glaucoma (PACG): (1) narrow iridocorneal angles (static gonioscopy, Task I) and (2) peripheral anterior synechiae (PAS) (dynamic gonioscopy, Task II) on OCT scans. International, cross-sectional, multicenter study. A total of 1.112 million images of 8694 volume scans (2294 patients) from 3 centers were included in this study (Task I, training/internal validation/external testing: 4515, 1101, and 2222 volume scans, respectively; Task II, training/internal validation/external testing: 378, 376, and 102 volume scans, respectively). For Task I, a narrow angle was defined as an eye in which the posterior pigmented trabecular meshwork was not visible in more than 180° without indentation in the primary position captured in the dark room from the scans. For Task II, PAS was defined as the adhesion of the iris to the trabecular meshwork. The diagnostic performance of the 3D DGS was evaluated in both tasks with gonioscopic records as reference. The area under the curve (AUC), sensitivity, and specificity of the 3D DGS were calculated. In Task I, 29.4% of patients had a narrow angle. The AUC, sensitivity, and specificity of 3D DGS on the external testing datasets were 0.943 (0.933–0.953), 0.867 (0.838–0.895), and 0.878 (0.859–0.896), respectively. For Task II, 13.8% of patients had PAS. The AUC, sensitivity, and specificity of 3D DGS were 0.902 (0.818–0.985), 0.900 (0.714–1.000), and 0.890 (0.841–0.938), respectively, on the external testing set at quadrant level following normal clinical practice; and 0.885 (0.836–0.933), 0.912 (0.816–1.000), and 0.700 (0.660–0.741), respectively, on the external testing set at clock-hour level. The 3D DGS is effective in detecting eyes with suspected PACG. It has the potential to be used widely in the primary eye care community for screening of subjects at high risk of developing PACG. [ABSTRACT FROM AUTHOR]

To assess anatomic changes after laser peripheral iridotomy (LPI) and predictors of angle widening based on anterior segment (AS) OCT and angle opening based on gonioscopy. Prospective observational study. Primary angle-closure suspects (PACSs) 50 to 70 years of age. Participants of the Zhongshan Angle Closure Prevention (ZAP) Trial underwent gonioscopy and AS-OCT imaging at baseline and 2 weeks after LPI. Primary angle-closure suspect was defined as the inability to visualize pigmented trabecular meshwork in 2 or more quadrants on static gonioscopy. Laser peripheral iridotomy was performed on 1 eye per patient in superior (between 11 and 1 o'clock) or temporal or nasal locations (at or below 10:30 or 1:30 o'clock). Biometric parameters in horizontal and vertical AS-OCT scans were measured and averaged. Linear and logistic regression modeling were performed to determine predictors of angle widening, defined as change in mean angle opening distance measured at 750 μm from the scleral spur (AOD 750); poor angle widening, defined as the lowest quintile of change in mean AOD 750 ; and poor angle opening, defined as residual PACS after LPI based on gonioscopy. Anatomic changes and predictors of angle widening and opening after LPI. Four hundred fifty-four patients were included in the analysis. Two hundred nineteen underwent superior LPI and 235 underwent temporal or nasal LPI. Significant changes were found among most biometric parameters (P < 0.006) after LPI, including greater AOD 750 (P < 0.001). One hundred twenty eyes (26.4%) showed residual PACS after LPI. In multivariate regression analysis, superior LPI location (P = 0.004), smaller AOD 750 (P < 0.001), and greater iris curvature (P < 0.001), were predictive of greater angle widening. Temporal or nasal LPI locations (odds ratio [OR], 2.60, P < 0.001) was predictive of poor angle widening. Smaller mean gonioscopy grade (OR, 0.34, 1-grade increment) was predictive of poor angle opening. Superior LPI location results in significantly greater angle widening compared with temporal or nasal locations in a Chinese population with PACS. This supports consideration of superior LPI locations to optimize anatomic changes after LPI. [ABSTRACT FROM AUTHOR]

Purpose To investigate central and peripheral corneal endothelial cell density ( ECD) in relation to Baerveldt ( BV) glaucoma drainage device ( GDD) tube corneal ( TC) distance. Methods Prospective study of all patients scheduled for glaucoma tube surgery with 36 months follow-up. A BV GDD was inserted into the anterior chamber ( AC). Anterior segment optical coherence tomography (AS-OCT) scans were made to determine the TC distance. Central and peripheral ECD was measured, preoperatively and at 3, 6, 12, 24 and 36 months postoperatively. Results Fifty-three eyes were included [primary open-angle glaucoma, ( n = 13); secondary glaucoma, ( n = 30); and primary angle-closure glaucoma, ( n = 10)]. Central ECD significantly decreased during follow-up, with a mean decrease of 4.54% per year (p < 0.001), and 6.57% in the peripheral quadrant closest to the BV GDD tube ( PQC, p < 0.001). In the PQC, a yearly decrease of 1.57% was shown after transiridial tube placement versus 7.43% after placement 'free' into the AC (p = 0.006). Endothelial cell (EC) loss was related to TC distance (mean 1.69 mm), with a central loss of 6.20% and 7.25% in the PQC per year with shorter TC distances, versus a central loss of 4.11% and 5.77% in the PQC per year with longer TC distances (outside mean ± 2 SD, p < 0.001). A difference in EC loss by glaucoma subtype was not identified. Conclusion The TC distance is of significant influence on corneal ECD, a shorter TC distance causing more severe EC loss, especially in the PQC. Transiridial placement of the BV GDD tube seems safer than placement 'free' into the AC. [ABSTRACT FROM AUTHOR]

The aim of this study is to compare a portable spectral domain optical coherence tomography (SD-OCT) device with a non-portable SD-OCT for the identification of anterior chamber angle parameters based on location of Schwalbe's line (SL) and to measure their reproducibility. 99 eyes from 46 normal, healthy participants underwent imaging of the inferior iridocorneal angle with the iVue and Cirrus SD-OCT under well-controlled low-light conditions. SL-angle opening distance (SL-AOD) and SL-trabecular iris space area (SL-TISA) were measured by masked, certified graders at the Doheny Image Reading Center using customized Image J grading software. Inter- and intrainstrument, as well as inter- and intraobserver reproducibility of SL-AOD and SL-TISA measurements were evaluated with intraclass correlation coefficients (ICCs) and Bland-Altman plots with limits of agreement. The mean SL-AOD was 0.814 ± 0.315 mm with the iVue and 0.797 ± 0.294 mm with the Cirrus. The mean SL-TISA was 0.247 ± 0.112 mm with iVue and 0.259 ± 0.113 mm with Cirrus. Interinstrument correlation coefficients ( r) were 0.93 ( P < 0.0001), 0.92 ( P < 0.0001), and 0.92 ( P < 0.0001) for SL_AOD and SL_TISA, respectively. Intraclass correlation coefficient showing the degree of agreement among SL-AOD and SL-TISA was 0.923 (95 % confidence interval 0.885-0.948) and 0.921 (95 % confidence interval 0.883-0.947) for both devices. The agreement for intrainstrument (ICCs > 0.95), intragrader (ICCs > 0.93), and intergrader (ICCs > 0.96) was excellent. Excellent agreement between the two devices was also documented with Bland-Altman analysis. Both instruments provide consistent and reproducible measurements of anterior chamber angle metrics. [ABSTRACT FROM AUTHOR]

Background: To investigate anterior scleral thickness in a cohort of healthy subjects using enhanced depth imaging anterior segment optical coherence tomography. Methods: Observational case series. The mean scleral thickness in the inferonasal, inferotemporal, superotemporal, and superonasal quadrant was measured 2 mm from the scleral spur on optical coherence tomography in healthy volunteers. Results: Fifty-three eyes of 53 Caucasian patients (25 male and 28 female) with an average age of 48.6 years (range: 18 to 92 years) were analysed. The mean scleral thickness was 571 μm (SD 84 μm) in the inferonasal quadrant, 511 μm (SD 80 μm) in the inferotemporal quadrant, 475 (SD 81 μm) in the superotemporal, and 463 (SD 64 μm) in the superonasal quadrant. The mean scleral thickness was significantly different between quadrants ( p < 0.0001, repeated measures one-way ANOVA). The association between average scleral thickness and age was statistically significant ( p < 0.0001, Pearson r = 0.704). Conclusions: Enhanced depth imaging optical coherence tomography revealed the detailed anatomy of the anterior sclera and enabled non-invasive measurements of scleral thickness in a non-contact approach. The anterior scleral thickness varies significantly between quadrants, resembling the spiral of Tillaux. An association of increasing scleral thickness with age was found. [ABSTRACT FROM AUTHOR]

PurposeTo compare the performance of anterior chamber volume (ACV) and anterior chamber depth (ACD) obtained using Scheimpflug imaging with angle opening distance (AOD500) and trabecular-iris space area (TISA500) obtained using spectral domain anterior segment optical coherence tomography (SD-ASOCT) in detecting narrow angles classified using gonioscopy.MethodsIn this prospective, cross-sectional observational study, 265 eyes of 265 consecutive patients underwent sequential Scheimpflug imaging, SD-ASOCT imaging, and gonioscopy. Correlations between gonioscopy grading, ACV, ACD, AOD500, and TISA500 were evaluated. Area under receiver operating characteristic curve (AUC), sensitivity, specificity, and likelihood ratios (LRs) were calculated to assess the performance of ACV, ACD, AOD500, and TISA500 in detecting narrow angles (defined as Shaffer grade ≤1 in all quadrants). SD-ASOCT images were obtained at the nasal and temporal quadrants only.ResultsTwenty-eight eyes (10.6%) were classified as narrow angles on gonioscopy. ACV correlated with gonioscopy grading (P<0.001) for temporal (r=0.204), superior (r=0.251), nasal (r=0.213), and inferior (r=0.236) quadrants. ACV correlated with TISA500 for nasal (r=0.135, P=0.029) and temporal (P=0.160, P=0.009) quadrants and also with AOD500 for nasal (r=0.498, P<0.001) and temporal (r=0.517, P<0.001) quadrants. For detection of narrow angles, ACV (AUC=0.935; 95% confidence interval (CI) =0.898-0.961) performed similar to ACD (AUC=0.88, P=0.06) and significantly better than AOD500 nasal (AUC=0.761, P=0.001), AOD500 temporal (AUC=0.808, P<0.001), TISA500 nasal (AUC=0.756, P<0.001), and TISA500 temporal (AUC=0.738, P<0.001). Using a cutoff of 113 mm3, ACV had 90% sensitivity and 88% specificity for detecting narrow angles. Positive and negative LRs for ACV were 8.63 (95% CI=7.4-10.0) and 0.11 (95% CI=0.03-0.4), respectively.ConclusionsACV measurements using Scheimpflug imaging outperformed AOD500 and TISA500 using SD-ASOCT for detecting narrow angles. [ABSTRACT FROM AUTHOR]

AimsTo report corneal endothelial cell loss and in vivo visualization of the Ahmed glaucoma valve implant in eyes with refractory glaucoma.MethodsTen eyes underwent Ahmed valve implant surgery and were followed-up for 12 months. Data collected included intraocular pressure (IOP), number of antiglaucoma medications and surgery-related complications. At 6 and 12 months postoperatively, the intracameral length of the drainage tube (ICL) and the distance between the tube and the cornea (T–C distance), and the iris (T–I distance) were assessed using anterior segment optical coherence tomography (AS-OCT). Heidelberg cornea tomograph II (HRT II) was used to measure the corneal endothelial cell density.ResultsMean (±SEM) preoperative IOP was 29.5±4 mmHg. Mean postoperative IOP was 11.6±2 at 12 months (P<0.01). Over a 6-month period, mean corneal endothelial loss was 7.9%±2.5 in the central and 7.5%±2.4 in the peripheral cornea (P<0.01). There was no correlation between central or peripheral corneal endothelial cell loss and the T–C, T–I distance or the ICL of the tube.ConclusionsCorneal endothelial cell loss occurs following Ahmed valve implant surgery, this appears to be multifactorial. AS-OCT and HRT II are promising methods for the follow-up of patients with a glaucoma drainage device. [ABSTRACT FROM AUTHOR]