Vertical asymmetry analysis of the macular microvasculature in epiretinal membrane patients with open-angle glaucoma.

To identify the usefulness of vertical asymmetry analysis of the retinal microvasculature in epiretinal membrane (ERM) patients accompanied by open-angle glaucoma (OAG). Subjects were divided into three groups: normal controls (group 1), patients with ERM (group 2), and patients with both ERM and OAG (group 3). Retinal nerve fiber layer (pRNFL) and ganglion cell-inner plexiform layer (GC-IPL) thicknesses, vessel density (VD), and the absolute vertical difference of pRNFL (vdRNFL), GC-IPL (vdGC-IPL), and VD (vdVD) were compared among groups. Logistic regression analysis was performed to determine the factors associated with OAG. Diagnostic accuracy based on the area under the curve (AUC) was conducted. The VD of the full area was 20.9 ± 1.2, 20.0 ± 1.9, and 18.8 ± 2.2 mm-1 (P < 0.001) for groups 1, 2, and 3, respectively. The vdVD differed significantly between group 2 and group 3 (P < 0.001), whereas vdRNFL (P = 0.531) and vdGC-IPL (P = 0.818) did not show a significant difference. Multivariate logistic analyses showed that average pRNFL thickness (OR 0.924, P = 0.001) and vdVD (OR 5.673, P < 0.001) were significant factors associated with OAG in ERM patients. The AUC of the vdVD was 0.81 (95% CI 0.72-0.89), and the combination of average pRNFL thickness and vdVD had the highest AUC (0.87; 95% CI 0.78-0.95; P < 0.001). ERM patients with OAG had a significantly thinner pRNFL thickness, lower macular VD, and higher vdVD than those without OAG. Average pRNFL thickness and vdVD were significant factors associated with OAG in patients with ERM. Additionally, the combination of average pRNFL thickness and vdVD showed good diagnostic performance for OAG in patients with ERM.

A comparison of peripapillary vessel density between subjects with normal-tension glaucoma and primary open-angle glaucoma with similar extents of glaucomatous damage.

The purpose of this study was to identify differences in retinal microvasculature impairments between patients with normal-tension glaucoma (NTG) and those with primary open-angle glaucoma (POAG) with similar extents of structural and visual field damage. Participants with glaucoma-suspect (GS), NTG, POAG, and normal controls were consecutively enrolled. Peripapillary vessel density (VD) and perfusion density (PD) were compared among the groups. Linear regression analyses were performed to identify the relationship between VD, PD and visual field parameters. The VDs of the full areas were 18.3 ± 0.7, 17.3 ± 1.7, 16.5 ± 1.7, and 15.8 ± 2.3 mm-1 in the control, GS, NTG, and POAG groups, respectively (P < 0.001). The VDs of the outer and inner areas and the PDs of all areas also differed significantly among the groups (all P < 0.001). In the NTG group, the VDs of the full, outer, and inner areas were significantly associated with all visual field parameters including the mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI). In the POAG group, the VDs of the full and inner areas were significantly associated with PSD and VFI but not with MD. In conclusion, with similar degrees of retinal nerve fiber layer thinning and visual field damage in both groups, the POAG group showed a lower peripapillary VD and PD than the NTG group. VD and PD were significantly associated with visual field loss.

The Weiss Ring, a Major Confounding Factor For Measurements of Peripapillary Retinal Nerve Fiber Layer Thickness: Short title: The Impact of the Weiss Ring On RNFL Thickness Measurements.

PURPOSE: To identify how the Weiss ring affects the measurement of mean and sectoral peripapillary retinal nerve fiber layer (pRNFL) thicknesses. DESIGN: Retrospective, cross-sectional study. METHODS: Subjects were divided into two groups: controls (control group) and subjects in which a Weiss ring was visible on optical coherence tomography fundus images (WR group). Mean and sectoral pRNFL thicknesses were compared between the two groups. RESULTS: A total of 205 eyes were enrolled: 131 eyes in the control group and 74 eyes in the WR group. The mean pRNFL thicknesses of the control group and WR group were 97.2 ± 6.7 µm and 94.6 ± 10.8 µm, respectively (P = .042). In sectoral thickness, the inferior sector of the WR group was 112.1 ± 23.2 µm, which was significantly thinner than that of the control group (125.5 ± 13.3 µm; P < .001). The Weiss ring was located in 10 eyes (13.5%) in the superior sector, 7 eyes (9.5%) in the temporal sector, 40 eyes (54.1%) in the inferior sector, and 17 eyes (23.0%) in the nasal sector. In analyses of reproducibility, the coefficient of variation and intraclass coefficient of the inferior sector measurement were 10.90% and 0.409, respectively, indicating low reliability of the measurement. CONCLUSIONS: Eyes with a Weiss ring showed thinner mean and inferior pRNFL thicknesses than normal controls, which would be a measurement error caused by the Weiss ring. This could be a major confounding factor for analyses of pRNFL changes, especially in glaucoma patients.

A Novel Technique for Measuring Ocular Duction Ranges.

Purpose: To report a novel technique for measuring ocular ductions and evaluate its performance in normal participants. Methods: We developed a laser pointer technique (LPT), a novel technique for quantitative measurement of ocular ductions. The device consists of a screen and headset with a laser pointer. Participants rotate their head while wearing the headset maintaining fixation on an optotype in the center of the screen until the target becomes blurry. Twenty-eight healthy volunteers were enrolled. The ocular ductions were measured with the LPT and compared to those of the Goldmann perimeter technique (GPT). Results: The mean horizontal and vertical duction ranges were 95.2° ± 10.1° and 84.1° ± 10.8° using the LPT, respectively, and 113.2° ± 14.1° and 105.8° ± 12.5° using the GPT, respectively; both were significantly greater in the GPT than LPT (both P < 0.05). The total time required for testing was shorter with the LPT compared to the GPT (56.1 ± 4.5 seconds and 92.3 ± 11.6 seconds, P = 0.003). Both the LPT and GPT measurements showed excellent intraobserver repeatability, and LPT showed better interobserver repeatability. Conclusions: Considering its reproducibility, accuracy, and simplicity, the LPT is expected to be useful for evaluating patients with ocular motility disorders as a first-order evaluation in the absence of sophisticated examination devices. Translational Relevance: The laser pointer technique, the new method for measuring ocular ductions, could be useful for evaluating patients with ocular motility disorders in clinical practice.

Effect of axial length on peripapillary microvasculature: An optical coherence tomography angiography study.

OBJECTIVE: To investigate the effects of axial length (AL) on the peripapillary microvascular density acquired from optical coherence tomography angiography (OCTA). METHODS: Retrospective observational study. A total of 111 eyes from 111 normal healthy subjects were examined. The subjects were divided into three groups according to the AL: Group 1 (AL: < 24.0 mm; 35 eyes), Group 2 (AL: 24.0-25.99 mm; 37 eyes), and Group 3 (AL: ≥ 26 mm; 39 eyes). Peripapillary OCTA images were acquired using 6× 6 mm angiography scans, and vessel density (VD) and perfusion density (PD) of the superficial capillary plexus were calculated automatically. VD and PD were compared among the three groups according to the distance from the optic disc (inner and outer rings). Linear regression analyses were also performed to identify clinical factors associated with average VD. RESULTS: The average ALs of Groups 1-3 were 23.33± 0.57, 25.05± 0.60, and 27.42± 0.82, respectively. Average VD (P = 0.009) and PD (P = 0.029) in the inner ring increased with increasing AL. However, average VD (P < 0.001) and PD (P < 0.001) in the outer ring decreased with AL increased; the same trends were found for the full areas (VD, p<0.001; PD, p = 0.001). Average VDs in the inner and outer rings were not associated (P = 0.938). CONCLUSIONS: Peripapillary VD and PD were significantly associated with AL. Depending on the distance from the disc, peripapillary VDs and PDs of the inner and outer rings were differentially affected by AL. Physicians should therefore consider the effects of AL in the analyses of peripapillary microvasculature.

Effects of Miosis on Anterior Chamber Structure in Glaucoma Implant Surgery.

We investigated changes in anterior chamber (AC) structure after miosis in phakic eyes and pseudophakic eyes with glaucoma. In this prospective study, patients scheduled for glaucoma implant surgery were examined using anterior segment optical coherence tomography before and after miosis. Four AC parameters (AC angle, peripheral anterior chamber (PAC) depth, central anterior chamber (CAC) depth, and AC area) were analyzed before and after miosis, and then compared between phakic and pseudophakic eyes. Twenty-nine phakic eyes and 36 pseudophakic eyes were enrolled. The AC angle widened after miosis in both the phakia and pseudophakia groups (p = 0.019 and p < 0.001, respectively). In the phakia group, CAC depth (p < 0.001) and AC area (p = 0.02) were significantly reduced after miosis, and the reductions in PAC depth, CAC depth, and AC area were significantly greater than in the pseudophakia group (all p < 0.05). Twenty-five patients (86.2%) in the phakia group and 17 (47.2%) in the pseudophakia group had reduced CAC depth (p = 0.004). Although miosis increased the AC angle in both groups, AC depth decreased in most phakic eyes and a substantial number of pseudophakic eyes. Preoperative miosis before glaucoma implant surgery may interfere with implant tube placement distant from the cornea during insertion into the AC.

Clinical outcomes of Ahmed glaucoma valve implantation without fixation of a plate: The free plate technique.

OBJECTIVE: This study compared surgical outcomes between free plate Ahmed glaucoma valve (FPAGV) implantation without plate fixation and conventional Ahmed glaucoma valve (CAGV) implantation with plate fixation. METHODS: A retrospective, comparative case series study. Patients with refractory glaucoma who underwent FPAGV or CAGV implantation and were followed >1 year were enrolled consecutively. We reviewed medical records, including data on postoperative intraocular pressure (IOP) and postoperative complications. The success rate and early postoperative hypertensive phase were compared between groups. RESULTS: A total of 74 patients with CAGV implantations and 36 patients with FPAGV implantations were studied. The average follow-up periods were 23.3 ± 2.6 months (CAGV) and 22.8 ± 2.8 months (FPAGV; p = 0.424). The surgery time was significantly shorter in the FPAGV group than in the CAGV group (42.6 ± 4.1 vs. 47.3 ± 5.4 min; p < 0.001). Postoperative IOP at 1 week and 1 month were significantly lower in the FPAGV group than in the CAGV group (11.8 ± 3.6 and 14.0 ± 5.3 mmHg vs. 18.7 ± 5.5 and 22.2 ± 5.2 mmHg; p = 0.012 and p = 0.002, respectively). An early postoperative hypertensive phase occurred in 62 eyes, and the frequency was greater in the CAGV group (50 eyes) than the FPAGV group (12 eyes; p = 0.001). There was no significant difference in postoperative complications between the two groups (p = 0.735). The success rate was 84.2% in the FPAGV group and 80.6% in the CAGV group 24 months after surgery (p = 0.367). CONCLUSION: FPAGV implantation was associated with a shorter surgery time, without any change in the extent of IOP reduction or complication rate. This procedure may be considered a good alternative for CAGV implantation in patients with refractory glaucoma.

Using the Thickness Map from Macular Ganglion Cell Analysis to Differentiate Retinal Vein Occlusion from Glaucoma.

PURPOSE: We hypothesized that the thickness map from macular ganglion cell analysis (GCA) acquired from spectral-domain optical coherence tomography can be used to differentiate retinal vein occlusion (RVO) from glaucoma. METHODS: In this retrospective case control study, 37 patients with resolved RVO and 74 patients with primary open-angle glaucoma (POAG) were enrolled. Two independent examiners diagnosed patients with RVO or POAG based on the topographic pattern in the GCA thickness map. Inter-observer agreement for a decision between RVO and POAG was assessed using kappa statistics. Diagnostic specificity and accuracy were calculated. RESULTS: Inter-observer agreement was good, with a kappa value of 0.765 (95% confidence interval, 0.634-0.896, p < 0.001). The diagnostic specificity of RVO from POAG using the GCA thickness map was 93.2% and diagnosis accuracy was 80.4%. CONCLUSIONS: An irregular GCA thickness map represents a simple and convenient differential diagnostic clue to distinguish RVO from POAG.

Effects of Topical Prostaglandin Analog on Macular Thickness Following Cataract Surgery with Postoperative Topical Bromfenac Treatment.

PURPOSE: To evaluate changes in macular thickness in patients continuing prostaglandin analog (PGA) treatment during the perioperative period involving bromfenac treatment. METHODS: Patients with glaucoma who were using a topical PGA were randomly assigned to two groups in this randomized controlled trial: PGA continuing study group and PGA discontinued glaucoma control group. Patients without ocular diseases other than cataract were enrolled into the non-glaucomatous group. After the cataract surgery, the patients used bromfenac twice per day for 4 weeks. Optical coherence tomography was performed in all patients preoperatively and at 1 month postoperatively. Changes in macular thickness were compared among the three groups. RESULTS: There were 32 eyes in the study group, 33 eyes in the glaucoma control group, and 58 eyes in the non-glaucomatous group. We found statistically significant postoperative changes in central macular thickness in all groups (4.30 ± 8.01 µm in the PGA continuing group, 9.20 ± 13.88 µm in the PGA discontinued group, and 7.06 ± 7.02 µm in the non-glaucomatous group, all p < 0.008), but no significant difference among the three groups (p = 0.161). Cystoid macular edema occurred in only one patient in the non-glaucomatous group (p = 0.568). CONCLUSIONS: Continuous use of PGAs during the perioperative period was not significantly associated with increased macular thickness after uncomplicated cataract surgery. In the absence of other risk factors (e.g., capsular rupture, uveitis, or diabetic retinopathy), discontinuing PGAs for the prevention of macular edema after cataract surgery with postoperative bromfenac treatment is unnecessary in patients with glaucoma.

Relationship between Tube Parameters and Corneal Endothelial Cell Damage after Ahmed Glaucoma Valve Implantation: A Comparative Study.

PURPOSE: We compared the clinical factors, including anterior chamber tube parameters, in patients with and without corneal endothelial cell damage after Ahmed glaucoma valve (AGV) implantation. METHODS: In this retrospective and comparative case series, patients who underwent AGV implantation were enrolled consecutively. Serial specular microscopy was performed before and after AGV implantation. Patients were divided into two groups depending on whether there was a significant decrease in corneal endothelial cell density (ECD), which was determined by each patient's rate of ECD change (%/year), calculated using linear regression analyses. Tube parameters such as the tube-cornea distance (TCD) and tube-cornea angle (TCA) were measured with anterior segment optical coherence tomography. Clinical factors related to the rate of ECD change were evaluated with regression analyses and compared between the two groups. The tipping point at which tube parameters became significantly associated with the rate of ECD change was identified with broken stick regression analyses. RESULTS: There were 30 eyes (32.3%) with ECD damage (group 1) and 63 eyes (67.7%) without damage (group 2). The mean rate of ECD change (%/year) was -18.82 ± 22.97 and 2.14 ± 2.93 in groups 1 and 2, respectively (p < 0.001). The TCA was the only clinical factor associated with the rate of ECD change (regression coefficient, ß = 1.254, p < 0.001). The tipping point in the TCA was 26.70° (95% confidence interval, CI: 23.75-29.64°). The mean TCD (mm) was 0.98 ± 0.38 and 1.26 ± 0.39 (p = 0.002), and the mean TCA (degrees) was 28.67 ± 7.79 and 36.35 ± 5.35 (p < 0.001) in groups 1 and 2, respectively. CONCLUSIONS: A wider TCA was protectively associated with the rate of ECD change, and the TCA was significantly narrower in patients with ECD damage. When inserting a tube into the anterior chamber, surgeons should therefore try to secure a wide TCA of about 30°. In patients with a narrow TCA after AGV implantation, increased attention should be directed toward whether ECD decreases continuously.

Long-term reproducibility of GC-IPL thickness measurements using spectral domain optical coherence tomography in eyes with high myopia.

Although ganglion cell inner plexiform layer (GC-IPL) analysis in the patients with high myopia is useful, there have been few reports to analyze of the reliability for long-term measured GC-IPL thickness. We aimed to analyze the long-term reproducibility of thickness measurements of the GC-IPL using spectral-domain optical coherence tomography (SD-OCT) in patients with high myopia and identify factors that affect such reproducibility. 99 eyes from 99 patients with high myopia without any other ophthalmc disorder such as glaucoma or retinal diseases were included. Two serial SD-OCT (Cirrus-HD) macular scans taken at ≧1 year intervals were analyzed. The intraclass correlation coefficient (ICC), coefficient of variation (CV), and test-retest standard deviation (TRTSD) of GC-IPL thickness measurements were assessed. The ICC, CV, and TRTSD of the mean GC-IPL thicknesses were 0.883, 5.9%, and 2.74, respectively. The ICCs of the six-sector GC-IPL thicknesses ranged from 0.740 to 0.904. The CVs of the minimal and all sectoral GC-IPL thicknesses were <10%. Measurement variances for the mean GC-IPL thicknesses showed significant relationshiups with chorioretinal atrophy and posterior staphyloma. There is high long-term reproducibility in GC-IPL thickness measurements using SD-OCT in high-myopia patients. The factors affecting this reproducibility include chorioretinal atrophy and posterior staphyloma.