Macular Optical Coherence Tomography Imaging in Glaucoma

The advent of spectral-domain optical coherence tomography has played a transformative role in posterior segment imaging of the eye. Traditionally, images of the optic nerve head and the peripapillary area have been used to evaluate the structural changes associated with glaucoma. Recently, there is growing evidence in the literature supporting the use of macular spectral-domain optical coherence tomography as a complementary tool for clinical evaluation and research purposes in glaucoma

Cataract surgery in eyes with filtered primary angle closure glaucoma.

PurposeTo evaluate the effect of cataract surgery on intraocular pressure (IOP) in filtered eyes with primary angle closure glaucoma (PACG).MethodsIn this prospective interventional case series, 37 previously filtered eyes from 37 PACG patients with mean age of 62.1±10.4 years were consecutively enrolled. All patients had visually significant cataracts and phacoemulsification was performed at least 12 months after trabeculectomy. Visual acuity, IOP and the number of glaucoma medications were recorded preoperatively, and 1, 3, 6 and 12 months after surgery. Anterior chamber (AC) depth was measured preoperatively and 3 months after cataract surgery with A-scan ultrasonography. The main outcome measure was IOP at 12 months.ResultsIOP was decreased significantly from 18.16±5.91 mmHg at baseline to 15.37±2.90 mmHg at final follow-up (P<0.01). The mean number of glaucoma medications was significantly decreased from 1.81±0.24 to 0.86±1.00 (P=0.001) at 1 year postoperatively. At final follow up, 36 (97.2%) eyes and 32 (86.4%) eyes had IOP≤21 and IOP≤18 mmHg, respectively; 14 (37.8%) eyes and 9 (24.3%) eyes had IOP≤21 and IOP≤18 mmHg without medications, respectively. The magnitude of IOP reduction was correlated with higher preoperative IOP (r=0.85, P<0.001), shallower preoperative AC depth (r=-0.38, P=0.01) and greater changes in AC depth (r=-0.39, P=0.01).ConclusionCataract surgery reduces IOP and the number of glaucoma medications in previously filtered PACG eyes. This reduction seems to be greater in patients with higher preoperative IOP and shallower anterior chambers

Qualitative evaluation of anterior segment in angle closure disease using anterior segment optical coherence tomography.

PURPOSE: To evaluate different mechanisms of primary angle closure (PAC) and to quantify anterior chamber (AC) parameters in different subtypes of angle closure disease using anterior segment optical coherence tomography (AS-OCT). METHODS: In this prospective study, 115 eyes of 115 patients with angle closure disease were included and categorized into three groups: 1) fellow eyes of acute angle closure (AAC; 40 eyes); 2) primary angle closure glaucoma (PACG; 39 eyes); and 3) primary angle closure suspect (PACS; 36 eyes). Complete ophthalmic examination including gonioscopy, A-scan biometry, and AS-OCT were performed. Based on the AS-OCT images, 4 mechanisms of PAC including pupillary block, plateau iris configuration, thick peripheral iris roll (PIR), and exaggerated lens vault were evaluated. Angle, AC, and lens parameter variables were also evaluated among the three subtypes. RESULTS: There was a statistically significant difference in the mechanism of angle closure among the three groups (p = 0.03). While the majority of fellow eyes of AAC and of PACS eyes had pupillary block mechanism (77.5% and 75%, respectively), only 48.7% of PACG eyes had dominant pupillary block mechanism (p = 0.03). The percentage of exaggerated lens vault and plateau iris mechanisms was higher in PACG eyes (25.5% and 15.4%, respectively). Fellow eyes of AAC had the shallowest AC (p = 0.01), greater iris curvature (p = 0.01), and lens vault (p = 0.02) than PACS and PACG eyes. Iris thickness was not significantly different among the three groups (p = 0.45). CONCLUSION: Using AS-OCT, we found that there was a statistically significant difference in the underlying PAC mechanisms and quantitative AC parameters among the three subtypes of angle closure disease

Qualitative evaluation of anterior segment in angle closure disease using anterior segment optical coherence tomography.

PURPOSE: To evaluate different mechanisms of primary angle closure (PAC) and to quantify anterior chamber (AC) parameters in different subtypes of angle closure disease using anterior segment optical coherence tomography (AS-OCT). METHODS: In this prospective study, 115 eyes of 115 patients with angle closure disease were included and categorized into three groups: 1) fellow eyes of acute angle closure (AAC; 40 eyes); 2) primary angle closure glaucoma (PACG; 39 eyes); and 3) primary angle closure suspect (PACS; 36 eyes). Complete ophthalmic examination including gonioscopy, A-scan biometry, and AS-OCT were performed. Based on the AS-OCT images, 4 mechanisms of PAC including pupillary block, plateau iris configuration, thick peripheral iris roll (PIR), and exaggerated lens vault were evaluated. Angle, AC, and lens parameter variables were also evaluated among the three subtypes. RESULTS: There was a statistically significant difference in the mechanism of angle closure among the three groups (p = 0.03). While the majority of fellow eyes of AAC and of PACS eyes had pupillary block mechanism (77.5% and 75%, respectively), only 48.7% of PACG eyes had dominant pupillary block mechanism (p = 0.03). The percentage of exaggerated lens vault and plateau iris mechanisms was higher in PACG eyes (25.5% and 15.4%, respectively). Fellow eyes of AAC had the shallowest AC (p = 0.01), greater iris curvature (p = 0.01), and lens vault (p = 0.02) than PACS and PACG eyes. Iris thickness was not significantly different among the three groups (p = 0.45). CONCLUSION: Using AS-OCT, we found that there was a statistically significant difference in the underlying PAC mechanisms and quantitative AC parameters among the three subtypes of angle closure disease

Topical latanoprost does not cause macular thickening after uncomplicated cataract surgery.

PurposeTo explore changes in central macular thickness (CMT) after a two-month period of glaucoma therapy with topical latanoprost after uneventful phacoemulsification.MethodsForty-one eyes of 31 patients with primary open angle or pseudoexfoliative glaucoma who required glaucoma medications after cataract surgery were prospectively enrolled. All eyes had undergone uneventful phacoemulsification with intraocular lens implantation at least 4 months before initiation of latanoprost. After a complete ophthalmic examination, spectral-domain optical coherence tomography (SD-OCT) and fluorescein angiography (FA) were performed at baseline before starting latanoprost. All eyes received latanoprost for 2 months, and clinical examinations were repeated one and two months afterwards; OCT and FA were repeated after 2 months. Outcome measures were CMT and loss of more than 2 lines of best corrected visual acuity (BCVA).ResultsMean patient age was 71.6±7.8 years. Intraocular pressure decreased from 21.5±3.4 mmHg to 14.4±2.6 mmHg (p<0.001) at 2 months. None of the eyes developed reduction of BCVA exceeding 2 lines, or angiographic cystoid macular edema (CME). Likewise no significant change was noted in CMT (249.9±29.8 vs 248.8±30.7µm), average macular thickness (274.5±15.0 vs 273.8±17.0µm), or macular volume (9.6±1.0 vs 9.6±1.1µm2) after treatment as compared to baseline (P>0.05 for all comparisons).ConclusionTopical use of latanoprost later than 4 months after uncomplicated cataract surgery does not seem to predispose to increased macular thickness or CME and may safely be used in this setting

Lamina Cribrosa and Choroid Features and Their Relationship to Stage of Pseudoexfoliation Glaucoma.

PurposeTo better understand the relationship of lamina cribrosa (LC) and choroid features to the severity of pseudoexfoliation glaucoma (PXG).MethodsIn this cross-sectional study, 137 eyes of 122 subjects (47 eyes with moderate/advanced PXG [mean deviation (MD), -15.0 ± 7.7 dB], 34 eyes with mild PXG [MD, -2.7 ± 1.5 dB], 32 aged-matched pseudoexfoliation syndrome [PXS] eyes, and 24 aged-matched control eyes) were investigated. Optic discs, LC thickness, and anterior LC depth (ALD; midsuperior, center, and midinferior) as well as peripapillary choroidal thickness were determined. Linear mixed modeling was used to adjust for age, sex, and axial length.ResultsA progressive decrease in LC thickness was found when comparing controls (271.9 ± 61.3 μm), PXS (212.6 ± 51.5 μm), mild PXG (180.8 ± 24.6 μm), and moderate/advance PXG (138.9 ± 37.5 μm) (P < 0.001). ALD was greater (P < 0.001) in moderate/advance glaucoma (306.7 ± 105.3 μm) and mild PXG (209.5 ± 79.7 μm) compared with PXS (155 ± 86.7 μm) and healthy controls (149.2 ± 103 μm). Although eyes with moderate/advance PXG had the thinnest choroid (117.2 ± 36.6 μm), choroidal thickness was comparable in mild PXG, PXS, and controls (150.0 ± 46.1, 159.7 ± 65.5, and 157.5 ± 51.1 μm, respectively; P = 0.002). Worse MD was the only factor associated with thinner LC (β = 2.344, P < 0.001) and choroid (β = 1.717, P = 0.009 μm) in PXG eyes. Higher IOP (β = 4.305, P = 0.013) and worse MD (β = -6.390, P < 0.001) were associated with deeper ALD in PXG.ConclusionsIn pseudoexfoliation, LC thinning is an early sign, and there is progressive thinning with advancing glaucoma. Choroidal thinning is observable only with moderate/advanced glaucoma. In PXG eyes, LC thickness, depth, and peripapillary choroidal thickness are associated with glaucoma severity

Peripapillary and macular choroidal thickness in glaucoma.

PurposeTo compare choroidal thickness (CT) between individuals with and without glaucomatous damage and to explore the association of peripapillary and submacular CT with glaucoma severity using spectral domain optical coherence tomography (SD-OCT).MethodsNinety-one eyes of 20 normal subjects and 43 glaucoma patients from the UCLA SD-OCT Imaging Study were enrolled. Imaging was performed using Cirrus HD-OCT. Choroidal thickness was measured at four predetermined points in the macular and peripapillary regions, and compared between glaucoma and control groups before and after adjusting for potential confounding variables.ResultsThe average (± standard deviation) mean deviation (MD) on visual fields was -0.3 (±2.0) dB in controls and -3.5 (±3.5) dB in glaucoma patients. Age, axial length and their interaction were the most significant factors affecting CT on multivariate analysis. Adjusted average CT (corrected for age, axial length, their interaction, gender and lens status) however, was not different between glaucoma patients and the control group (P=0.083) except in the temporal parafoveal region (P=0.037); nor was choroidal thickness related to glaucoma severity (r=-0.187, P=0.176 for correlation with MD, r=-0.151, P=0.275 for correlation with average nerve fiber layer thickness).ConclusionsChoroidal thickness of the macular and peripapillary regions is not decreased in glaucoma. Anatomical measurements with SD-OCT do not support the possible influence of the choroid on the pathophysiology of glaucoma

Ahmed Glaucoma Valve with Adjunctive Amniotic Membrane for Refractory Glaucoma

Purpose: To evaluate the efficacy and safety of Ahmed Glaucoma Valve (AGV) implantation with adjunctive use of preserved amniotic membrane for surgical management of refractory glaucoma. Methods: Seven patients (5 female subjects) with refractory glaucoma were included in the study. An AGV (model FP7) was implanted in the usual manner and was covered with two layers of cryopreserved human amniotic membrane. Intraocular pressure (IOP) and number of glaucoma medications before and after surgery, and complications were evaluated. Results: Mean duration of follow-up was 16.8±4.6 months. Mean preoperative IOP was 31.7±4.4 mmHg which was reduced to 17.7±6.1 mmHg at final follow-up (P=0.01, Wilcoxon U test). Although the number of topical medications was also reduced (mean decrease of 0.85 drops), this decrease was not significant (P=0.10, Wilcoxon U test). None of the eyes developed encapsulation after surgery; only one case was complicated by posterior migration of the implant resulting in failure. Conclusion: Glaucoma shunt surgery using the AGV with adjunctive amniotic membrane seems to be a safe and effective procedure which may reduce the risk of bleb encapsulation in refractory glaucomas