Profiles and Clinical Characteristics of Newly Diagnosed Glaucoma in Urban Korea: A Multicenter Study

Purpose@#To explore the clinical characteristics and profiles of newly diagnosed glaucoma subtypes in urban Korea. @*Methods@#All newly diagnosed glaucoma patients enrolled in the participating ophthalmology outpatient clinics were in-cluded. A review of medical history including family history of glaucoma was conducted. The patients underwent complete ophthalmologic examinations including visual field test. The diagnosis of glaucoma was based on the International Society of Geographical and Epidemiological Ophthalmology criteria developed by glaucoma specialists. @*Results@#A total of 198,671 patients visited the participating ophthalmology outpatient clinics during the study period (from January 1, 2001 to June 30, 2016), of which 5,530 (2.8%) were diagnosed with glaucoma. The mean age of the newly diag-nosed glaucoma patients was 52.0 ± 17.3 years (range, 6 to 89) and 2,830 patients were male (51.2%). The mean untreated in-traocular pressure and vertical cup-to-disc ratio of the optic nerve head of newly diagnosed glaucoma eyes were 22.1 ± 10.6 mmHg and 0.66 ± 0.22, respectively. The most frequently observed subtypes of glaucoma were: normal tension glaucoma (33.0%) primary open-angle glaucoma (28.4%), ocular hypertension (11.1%), chronic angle-closure glaucoma (6.8%), neovas-cular glaucoma (5.2%), glaucoma associated with inflammation (3.8%), acute angle-closure glaucoma (3.3%), and glaucoma associated with aphakia or pseudophakia (2.2%). @*Conclusions@#Normal tension glaucoma was the most frequently observed glaucoma subtype in urban ophthalmology outpa-tient clinics in Korea.

New Non-contact Tonometer HNT-1P Reliability: Comparing Intraocular Pressure, Central Corneal Thickness, and Corrected Intraocular Pressure

Purpose@#To assess the reliability of a new non-contact tonometer, HNT-1P, by comparing its intraocular pressure (IOP), central corneal thickness (CCT), and corrected IOP (cIOP) measurements with the IOP measured by Goldmann applanation tonometry (GAT), the CCT measured with ultrasound pachymetry (USP), and the cIOP derived from GAT IOP and USP CCT. @*Methods@#A total of 120 eyes of 65 healthy or glaucoma suspects were included in this study. The IOP was measured with the HNT-1P and GAT. The CCT was determined using the HNT-1P and USP. The IOP measured with GAT was corrected according to the CCT measured by USP. The correlations of the measurements obtained with the various instruments were evaluated using Pearson’s correlation coefficient, and the agreement was assessed using Bland-Altman plots. @*Results@#The average IOP measured with the HNT-1P and GAT was 14.8 ± 5.1 mmHg and 15.6 ± 5.2 mmHg, respectively, and the correlation coefficient between the two IOP measurements was 0.964 (p < 0.001). The mean CCT was 553.5 ± 27.4 μm using the HNT-1P and 550.6 ± 26.3 μm using USP, and the correlation coefficient between the two measurements was 0.913 (p < 0.001). The average cIOP was 14.6 ± 5.0 and 13.4 ± 6.5 mmHg according to the HNT-1P and GAT, respectively, and the correlation coefficient between the two corrected measurements was 0.956 (p < 0.001). Bland-Altman plots showed a high degree of agreement between the HNT-1P measurements and those of the other devices. @*Conclusions@#The new non-contact HNT-1P tonometer provided reliable IOP, CCT, and cIOP measurements when compared with GAT and USP. HNT-1P could therefore be used clinically for reliable and accurate measurements of the IOP, CCT, and cIOP.

Progressive Optic Disc Tilt in Young Myopic Glaucomatous Eyes

PURPOSE: To explore the progressive change and associated factors of optic disc tilt in young myopic glaucomatous eyes by analyzing long-term follow-up data.METHODS: Optic disc images were obtained from spectral-domain optical coherence tomography enhanced depth imaging from at least five different visits. At each visit, the disc tilt angle (DTA), defined as the angle between the Bruch's membrane opening plane and the optic canal plane, was estimated at the central frame that passes through the optic disc. Glaucoma progression was assessed on the basis of changes noted on serial optic disc and retinal nerve fiber layer photographs or changes in the visual field (VF). A linear mixed effect model was used to assess the influence of parameters (age, sex, baseline and follow-up intraocular pressure, retinal nerve fiber layer thickness, VF mean deviation, axial length, central corneal thickness), and presence of glaucomatous progression upon DTA change.RESULTS: A total of 26 eyes of 26 young myopic primary open-angle glaucoma patients (axial length >24.0 mm; mean age, 25.1 ± 4.0 years; mean follow-up, 3.3 ± 0.9 years) were included. DTA was 7.0 ± 3.4 degrees at baseline and 8.3 ± 3.8 degrees at last visit, which represents a significant difference (p < 0.001). Worse VF mean deviation (p < 0.001) and longer axial length (p = 0.006) were significantly associated with DTA increase.CONCLUSIONS: Young myopic glaucomatous eyes showed progressive optic disc tilting. Progressive optic disc tilting in young myopic glaucomatous eyes may be related to either continuous axial myopic shift or glaucomatous structural change.

Additive Role of Optical Coherence Tomography Angiography Vessel Density Measurements in Glaucoma Diagnoses

PURPOSE: This study compared the glaucoma diagnostic abilities of optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). In addition, the possibility of enhancing diagnostic capability by combining the two modalities was investigated. METHODS: A total of 131 healthy eyes and 113 glaucomatous eyes were imaged by both OCT and OCTA. In OCT, glaucoma was defined as when the color of the superior or inferior quadrant of the peripapillary retinal nerve fiber layer thickness map was yellow (borderline, <5%) or red (outside normal limits, <1%). In OCTA, glaucoma was determined using the cut-off value of the superior or inferior peripapillary vessel density, calculated after receiver operating characteristic curve analysis. Sensitivity and specificity were determined by OCT alone, by OCTA alone, or by OCT and OCTA combined. RESULTS: The sensitivity of OCT (86.7%) was better than that of OCTA (74.3%), whereas the specificity of OCTA (87.0%) was better than that of OCT (67.9%). When these two modalities were combined, both sensitivity and specificity were enhanced (90.3% and 92.4%, respectively). Among the 131 eyes, 32 were misdiagnosed as glaucomatous by OCT but accurately diagnosed as normal by OCTA. These eyes were myopic, with a longer axial length and a thinner and temporally displaced peak of peripapillary retinal nerve fiber layer thickness, causing the false positive result in OCT. CONCLUSIONS: When OCTA was combined with OCT, the specificity of glaucoma diagnoses were enhanced. OCTA may compensate for the shortcomings of OCT in the diagnosis of glaucoma.

Spatial and Temporal Characteristics of Visual Field Progression in Glaucoma Assessed by Parallel Factor Analysis

PURPOSE: To explore spatial and temporal characteristics of glaucomatous visual field (VF) progression through multi-way decomposition of data. METHODS: Six serial VF exams with intervals of 6.0 ± 1.0 months in 121 pre-perimetric glaucoma eyes and 80 perimetric glaucoma eyes were arranged into a three-dimensional cube. The data were decomposed using parallel factor analysis. RESULTS: Three tri-linear components (i.e., spatial scores, temporal loadings, and subject-specific loadings) were identified. Component 1 clearly showed differences between superior and inferior hemispheres, linear trends over time, and wide variability in perimetric glaucoma. Findings were compatible with well-known characteristics of glaucomatous VF defects. Component 2 showed nasal and central areas in contrast with superior, inferior, and temporal peripheral locations, whereas component 3 showed a contrast between nasal and temporal hemispheres. Both components 2 and 3 failed to show clear temporal trends. CONCLUSIONS: Identification of spatio-temporal patterns shows new possibilities for a multi-way decomposition methodology for earlier diagnosis and prediction of glaucomatous VF progression.

Effects of Choroidal Thickness on Refractive Outcome Following Cataract Surgery in Primary Angle Closure

PURPOSE: To identify the preoperative biometric factors, including subfoveal choroidal thickness (CT), associated with refractive outcome after cataract surgery in eyes with primary angle closure (PAC). METHODS: This study included 50 eyes of 50 PAC patients who underwent uneventful cataract surgery. Preoperatively, anterior segment parameters including anterior chamber depth (ACD) and lens vault were determined by anterior segment optical coherence tomography. Subfoveal CT was measured by spectral domain optical coherence tomography enhanced depth imaging before and at one month after surgery. Mean refractive error (MRE) was calculated as the difference in spherical equivalent between actual postoperative refraction determined one month postoperatively and that predicted using each of three IOL calculation formulas (SRK/II, SRK/T, and Haigis). Regression analyses were performed to investigate potential associations between MRE and putative factors. RESULTS: Mean ACD was 1.9 ± 0.4 mm, and preoperative subfoveal CT was 250.8 ± 56.9 µm. The SRK/T (MRE, 0.199 ± 0.567 diopters [D]) and Haigis (MRE, 0.190 ± 0.727 D) formulas showed slight hyperopic shift, while the SRK/II formula demonstrated a myopic shift (MRE, −0.077 ± 0.623 D) compared with that expected after cataract surgery. Mean absolute refractive error was not significantly different between formulas. Higher preoperative lens vault and shallower ACD were associated with a hyperopic shift in all formulas, but not in a statistically significant manner. Thicker preoperative subfoveal choroid was associated with a myopic shift after cataract surgery in all formulas (SRK/II: β = −0.511, p < 0.001; SRK/T: β = −0.652, p < 0.001; Haigis: β = −0.671, p < 0.001). Greater postoperative reduction of subfoveal CT was associated with a myopic shift after cataract surgery in all formulas (SRK/II: β = −0.511, p < 0.001; SRK/T: β = −0.652, p < 0.001; Haigis: β = −0.671, p < 0.001). CONCLUSIONS: Our results indicate that preoperative subfoveal CT and the difference between pre- and postoperative subfoveal CT are significant factors for predicting refractive error after cataract surgery in PAC patients. These findings should be considered when performing cataract surgery to optimize visual outcomes.

Influence of Vitrectomy-related Factors on the Outcome of Ahmed Glaucoma Valve Implantation

PURPOSE: To evaluate the outcome of Ahmed glaucoma valve (AGV) implantation in eyes with refractory secondary glaucoma following pars plana vitrectomy (PPV) and the associated prognostic factors. METHODS: A total of 146 eyes in 146 patients who underwent AGV implantation after PPV (followed up for ≥1 year) were included. AGV implantation was considered successful when the intraocular pressure (IOP) was 6 to 21 mmHg regardless of using IOP-lowering medication. The hazard ratios (HRs) associated with surgical failure were determined with Cox proportional analysis. RESULTS: The most common cause for PPV was complications of proliferative diabetic retinopathy (50%). The mean and peak IOPs between PPV and AGV implantation were 26.9 ± 6.6 and 35.9 ± 10.2 mmHg, respectively. AGV implantation was performed on average 18.7 months after PPV, and its overall success rate was 80.1% during a mean follow-up period of 43.6 months. In multivariate analyses, rubeosis observed before AGV implantation (HR, 4.07; 95% confidence interval, 1.57 to 10.6; p = 0.004) and higher peak IOP before AGV (HR, 1.04; 95% confidence interval, 1.00 to 1.07; p = 0.034) were predictive of failure. However, no PPV-related factors were associated with the surgical outcome of AGV implantation. CONCLUSIONS: The outcome of AGV implantation is good in refractory glaucoma following PPV. Rubeosis after PPV and higher peak IOP before AGV are risk factors for poor outcomes. Patients who undergo PPV should be followed for the development of rubeosis and IOP control.

Relationship between Progressive Changes in Lamina Cribrosa Depth and Deterioration of Visual Field Loss in Glaucomatous Eyes

PURPOSE: To investigate the relationship between the progression of visual field (VF) loss and changes in lamina cribrosa depth (LCD) as determined by spectral-domain optical coherence tomography (SD-OCT) enhanced depth imaging in patients with primary open angle glaucoma (POAG). METHODS: Data from 60 POAG patients (mean follow-up, 3.5 ± 0.7 years) were included in this retrospective study. The LCD was measured in the optic disc image using SD-OCT enhanced depth imaging scanning at each visit. Change in the LCD was considered to either ‘increase’ or ‘decrease’ when the differences between baseline and the latest two consecutive follow-up visits were greater than the corresponding reproducibility coefficient value (23.08 µm, as determined in a preliminary reproducibility study). All participants were divided into three groups: increased LCD (ILCD), decreased LCD (DLCD), and no LCD change (NLCD). The Early Manifest Glaucoma Trial criteria were used to define VF deterioration. Kaplan-Meier survival analysis and Cox's proportional hazard models were performed to explore the relationship between VF progression and LCD change. RESULTS: Of the 60 eyes examined, 35.0% (21 eyes), 28.3% (17 eyes), and 36.7% (22 eyes) were classified as the ILCD, DLCD, and NLCD groups, respectively. Kaplan-Meier survival analysis showed a greater cumulative probability of VF progression in the ILCD group than in the NLCD (p < 0.001) or DLCD groups (p = 0.018). Increased LCD was identified as the only risk factor for VF progression in the Cox proportional hazard models (hazard ratio, 1.008; 95% confidence interval, 1.000 to 1.015; p = 0.047). CONCLUSIONS: Increased LCD was associated with a greater possibility of VF progression. The quantitative measurement of LCD changes, determined by SD-OCT, is a potential biomarker for the prediction of VF deterioration in patients with POAG.

Factors Associated with Outcomes of Combined Phacoemulsification and Ahmed Glaucoma Valve Implantation

PURPOSE: To evaluate outcomes and factors associated with surgical failure in patients who underwent combined phacoemulsification and Ahmed glaucoma valve (AGV) implantation. METHODS: This retrospective and longitudinal study enrolled 40 eyes (38 patients) that underwent combined phacoemulsification and AGV implantation. Visual acuity, intraocular pressure (IOP), and number of antiglaucoma medications were evaluated preoperatively and postoperatively. Complete success was defined as a last follow-up IOP of 6 to 21 mmHg without medication, qualified success as an IOP of 6 to 21 mmHg with medication, and failure as an IOP of >21 or <6 mmHg. RESULTS: The mean follow-up period was 18 ± 10 months. Preoperative diagnoses were chronic angle closure glaucoma (35.0%), neovascular glaucoma (22.5%), uveitic glaucoma (17.5%), primary open-angle glaucoma (15.0%), and other (10.0%). IOP decreased from a mean of 30.5 ± 8.7 to 14.5 ± 3.7 mmHg at the last follow-up visit (p < 0.001). Treatment was classified as qualified success in 18 eyes (45%), complete success in 15 (37.5%), and failure in seven (17.5%). Twenty-two eyes (55%) showed improvement in visual acuity. The most common postoperative complication was a transient hypertensive phase (five eyes, 12.5%). Tube-iris touch was associated with surgical failure (hazard ratio, 8.615; p = 0.008). CONCLUSIONS: Combined phacoemulsification and AGV implantation is an effective and safe surgical option for patients with refractory glaucoma and cataract. Postoperative tube-iris touch is an indicator of poor prognosis.

Macular Ganglion Cell Layer Assessment to Detect Glaucomatous Central Visual Field Progression

PURPOSE: To investigate the use of ganglion cell inner plexiform layer (GC-IPL) thickness, as measured by spectral domain optical coherence tomography, to detect central visual field (VF) progression. METHODS: This study included 384 eyes from 384 patients (219 preperimetric and 165 perimetric glaucomatous eyes; average follow-up, 4.3 years). Photographic assessment of retinal nerve fiber layer (RNFL) and serial VF analysis were performed to detect glaucoma progression in the central (within 10°) area. Study inclusion required at least five serial spectral domain optical coherence tomography exams at different visits. The long-term test-retest variability of average GC-IPL thicknesses was calculated in 110 stable preperimetric glaucomatous eyes. The sensitivity and specificity of GC-IPL measurements for the detection of central VF progression were calculated in an event-based analysis using the calculated variability as a cut-off and were compared with those of central RNFL photographic assessment. RESULTS: The intersession test-retest variability, defined as the 95% confidence interval, was 1.76 µm for average GC-IPL thickness. The sensitivity and specificity of the average GC-IPL thickness for detecting central VF progression were 60.7% and 78.9%, respectively. Among six sectors, the inferonasal GC-IPL sector showed the highest sensitivity (53.6%). The sensitivity of the ≥1 sector GC-IPL to detect central VF progression was significantly higher than that of central RNFL photographic progression (p = 0.013). Other GC-IPL parameters showed comparable sensitivity and specificity to detect central VF progression compared with RNFL photographic progression. CONCLUSIONS: Serial GC-IPL measurements show comparable performance in the detection of central glaucomatous VF progression to RNFL photographic assessment.

Clinical and Anterior Segment Anatomical Features in Primary Angle Closure Subgroups Based on Configurations of Iris Root Insertion

PURPOSE: To compare the clinical and anterior segment anatomical features in primary angle closure sub-groups based on configurations of iris root insertion. METHODS: Primary angle closure patients were imaged using anterior segment optical coherence tomography. Anterior chamber depth, iris curvature, iris thickness (IT) at the scleral spur and 500, 750, and 1,500 µm from the scleral spur (IT(0), IT(500), IT(750), and IT(1500)), lens vault, iris area, angle opening distance (AOD(500)), angle recess area (ARA(750)), and trabecular iris space area (TISA(750)) were measured. Iris root insertion was categorized into a non-basal insertion group (NBG) and basal insertion group (BG). RESULTS: In total, 43 eyes of 39 participants belonged to the NBG and 89 eyes of 53 participants to the BG. The mean age of participants was greater in the NBG than the BG (62.7 ± 5.7 vs. 59.8 ± 7.3 years, p = 0.043), and the baseline intraocular pressure was higher in the BG than the NBG (16.4 ± 4.4 vs. 14.9 ± 3.3 mmHg, p = 0.037). The BG showed a greater IT(0) (0.265 ± 0.04 vs. 0.214 ± 0.03 mm, p < 0.001) and iris area (1.59 ± 0.24 vs. 1.52 ± 0.27 mm2, p = 0.045), lower ARA(750) (0.112 ± 0.08 vs. 0.154 ± 0.08 mm2, p = 0.017) and AOD(500) (0.165 ± 0.07 vs. 0.202 ± 0.08 mm, p = 0.014) compared to the NBG. CONCLUSIONS: The BG had a narrower anterior chamber angle, thicker peripheral iris, and higher pretreatment intraocular pressure.

Comparison of the Progression of High- and Low-tension Glaucoma as Determined by Two Different Criteria

PURPOSE: To investigate and compare the progression of medically treated primary open angle glaucoma according to the baseline intraocular pressure (IOP). METHODS: This study included a total of 345 eyes from 345 patients (mean follow-up period, 4.5 years). Eyes were classified into either conventional normal tension glaucoma (cNTG, 21 mmHg) groups according to the conventional cut-off value of the IOP. Additionally, the median IOP (15 mmHg) was used to create two other groups (median NTG [mNTG] 15 mmHg). Using these values, 306, 39, 153, and 192 eyes were assigned to the cNTG, cHTG, mNTG, and mHTG groups, respectively. Glaucoma progression was determined either by optic disc/retinal nerve fiber layer photographs or serial visual field data. RESULTS: Mean reduction of IOP after medical treatment and of central corneal thickness was lower in the cNTG group, while the prevalence of disc hemorrhage and baseline visual field mean deviation did not differ between the cNTG and cHTG groups. A mean reduction in the IOP was observed after medical treatment, and central corneal thickness was lower in the mNTG group; disc hemorrhage was more frequent in the mNTG than in the mHTG group. Among the 345 analyzed eyes, 100 (29%) showed progression during the follow-up period. In the cHTG group, a higher baseline IOP (hazard ratio, 1.147; p = 0.024) was associated with glaucoma progression. Disc hemorrhage (hazard ratio, 15.533; p < 0.001) was also strongly associated with progression in the mNTG group. CONCLUSIONS: Baseline IOP was a significant risk factor for glaucoma progression in cHTG patients (10% of our total participants), while disc hemorrhage showed the strongest association with progression in the mNTG group, indicating that a cut-off value other than the conventional 21 mmHg is required to define true low-tension glaucoma in populations where NTG predominates among all glaucoma patients.

Comparison of Clinical Characteristics and Progression Rates of Bilaterally and Unilaterally Progressing Glaucoma

PURPOSE: To compare the clinical characteristics of unilaterally progressing glaucoma (UPG) and simultaneously bilaterally progressing glaucoma (BPG) in medically treated cases. METHODS: Primary open angle glaucoma patients were classified as having UPG or BPG according to an assessment of optic disc and retinal nerve fiber layer photographs and visual field analysis. Risk factors including the presence of systemic diseases (hypertension, diabetes, cerebrovascular accident, migraine, and dyslipidema) were compared between the UPG and BPG groups. Baseline characteristics and pre- and post-treatment intraocular pressure (IOP) were compared between the progressing eye (PE) and the non-progressing eye (NPE) within the same patient in the UPG group and between the faster progressing eye and the slower progressing eye in the BPG group. RESULTS: Among 343 patients (average follow-up period of 4.2 years), 43 were categorized into the UPG group and 31 into the BPG group. The prevalence of all analyzed systemic diseases did not differ between the two groups. PEs in the UPG group had more severe pathology in terms of baseline visual field parameters than NPEs (mean deviation -6.9 ± 5.7 vs. -2.9 ± 3.9 dB, respectively; p < 0.001). However, baseline IOP, mean follow-up IOP, and other clinical characteristics were not significantly different between the PE and the NPE in the UPG group. The progression rate was significantly higher in the faster progressing eye in patients with BPG than in the PE for patients with UPG (-3.43 ± 3.27 vs. -0.70 ± 1.26 dB/yr, respectively; p = 0.014). CONCLUSIONS: There were no significant differences in the prevalence of systemic diseases between the UPG and BPG groups. Simultaneously bilaterally progressing patients showed much faster progression rates than those with a unilaterally progressing eye.

Clinical Characteristics of First-Degree Relatives with Primary Open-Angle Glaucoma

PURPOSE: To investigate the clinical characteristics of first-degree relatives with primary open-angle glaucoma (POAG). METHODS: Forty-four POAG patients (22 pairs of eyes from 2 first-degree relatives) were followed for an average of 3.3 years. Baseline characteristics and follow-up data were analyzed. Baseline data consisted of baseline intraocular pressure (IOP), central corneal thickness (CCT), spherical equivalent, visual field mean deviation (VF MD) and average retinal nerve fiber layer (RNFL) thickness measured using optical coherence tomography (OCT). Follow-up data consisted of mean follow-up IOP, mean IOP reduction from baseline (%) and progression rates determined by linear regression analysis of either VF MD value or OCT RNFL thickness. Mean data of both eyes and the worse eye were compared between first-degree relatives of the same family. RESULTS: Among the 22 families, 16 pairs of eyes were from parent/offspring and 6 from siblings. No difference in mean baseline IOP and CCT were found between first-degree relatives. The older patients in parent-offspring families showed significantly more advanced glaucoma in terms of both VF and RNFL thickness, but were less myopic; however, no differences in variables were found between relatives in the 6 families composed of siblings. Among the 22 families, worse baseline VF MD was observed in younger patients compared with the older patients in 4 families. Mean follow-up IOP, mean IOP reduction from baseline, and progression rate did not differ between the older and the younger patient in each family. CONCLUSIONS: In our study, similar characteristics in terms of baseline IOP, IOP response to medication, and glaucoma progression rate were found in members of the same family. However, in some of the families, the younger patient had poorer baseline severity and more aggressive characteristics compared with the older patient, suggesting the clinical course of the disease may vary among first-degree relatives.

Assessment of Macular Ganglion Cell Loss Patterns in Neurologic Lesions That Mimic Glaucoma

PURPOSE: To evaluate patterns of macular retinal ganglion cell (RGC) loss measured by spectral domain optical coherence tomography in patients with neurologic lesions mimicking glaucoma. METHODS: We evaluated four patients with neurological lesions who showed characteristic patterns of RGC loss, as determined by ganglion cell thickness (GCT) mapping. RESULTS: Case 1 was a 30-year-old man who had been treated with glaucoma medication. A left homonymous vertical pattern of RGC loss was observed in his GCT map and a past brain magnetic resonance imaging (MRI) revealed a hemorrhagic lesion around the right optic radiation. Case 2 was a 72-year-old man with a pituitary adenoma who had a binasal vertical pattern of RGC loss that corresponded with bitemporal hemianopsia. Case 3 was a 77-year-old man treated for suspected glaucoma. His GCT map showed a right inferior quadratic pattern of loss, indicating a right superior homonymous quadranopsia in his visual field (VF). His brain MRI revealed a left posterior cerebral artery territory infarct. Case 4 was a 38-year-old woman with an unreliable VF who was referred for suspected glaucoma. Her GCT map revealed a left homonymous vertical pattern of RGC loss, which may have been related to a previous head trauma. CONCLUSIONS: Evaluation of the patterns of macular RGC loss may be helpful in the differential diagnosis of RGC-related diseases, including glaucoma and neurologic lesions. When a patient's VF is unavailable, this method may be an effective tool for diagnosing and monitoring transneuronal retrograde degeneration-related structural changes.

Augmentation of Filtering Blebs with Viscoelastics in Trabeculectomy

PURPOSE: To evaluate the clinical outcome of viscoelastics (VE, sodium hyaluronate)-augmented trabeculectomy (VAT, 66 eyes) and conventional trabeculectomy (CT, 57 eyes) for glaucomatous eyes. METHODS: In the VAT group, half of the anterior chamber space was filled with VE via the paracentesis site at the end of CT and a balanced salt solution was injected into the anterior chamber. This procedure induced migration of VE from the anterior chamber into the bleb space; thus the bleb was elevated with underlying VE. Follow-up examinations were performed until 1 year after surgery. Success was defined as the attainment of an intraocular pressure (IOP) greater than 5 mmHg and less than 22 mmHg. If IOP was in the range of success without antiglaucoma medication, it was regarded as a complete success. RESULTS: The mean postoperative IOP was significantly lower in the VAT group at postoperative 1 day, 1 week, and 1 month. The complete success rate was significantly higher in the VAT group (89%) than in the CT group (75%), though the qualified success rate was not different between the two groups. The number of IOP-lowering medications at postoperative 1 year was significantly higher in the CT group (1.30 ± 1.08 vs. 0.73 ± 0.98, p = 0.003). Among postoperative procedures, laser suture lysis was required less frequently in the VAT group (p < 0.001). CONCLUSIONS: Placing VE within the bleb at the end of surgery may result in better IOP control and less need for IOP-lowering medication without any additional materials, cost, or time.

Relationship between the Lamina Cribrosa, Outer Retina, and Choroidal Thickness as Assessed Using Spectral Domain Optical Coherence Tomography

PURPOSE: To evaluate the characteristics and relationship between peripapillary choroidal thickness (pCT), lamina cribrosa thickness (LCT), and peripapillary outer retinal layer thickness (pORT) as determined using spectral domain optical coherence tomography (SD-OCT) enhanced depth imaging (EDI). METHODS: In total, 255 participants were included (87 healthy subjects, 87 glaucoma suspects (GS), and 81 glaucoma cases). The pORT, defined as the thickness between the posterior outer plexiform layer and the retinal pigment epithelium (RPE) interface, and the pCT, between the outer margin of the RPE and the choroidal-scleral interface, were manually measured using EDI scanning of the circumpapillary retinal nerve fiber layer (RNFL). LCT was determined by EDI scanning of the optic nerve head (ONH). Baseline characteristics, including axial length (AXL) and the SD-OCT measurements of the participants, were compared among the three groups. The correlation between putative factors and pCT was determined using univariate and multivariate linear regression analyses. RESULTS: In all three groups, both pORT and pCT were thinnest in the inferior area among the four quadrants. In the healthy group, the mean peripapillary RNFL, pORT, and LCT were significantly greater in comparison with those of the GS and glaucoma groups (p < 0.001, p < 0.038, and p < 0.001, respectively). The pCT demonstrated no significant differences among the three groups (p = 0.083). Only age and AXL were associated with pCT by multivariate analysis. CONCLUSIONS: The pCT is substantially thinner in the inferior area of the ONH. In addition, the pCT demonstrates the strongest correlation with age and AXL, but was not associated with glaucoma or LCT.

Clinical Characteristics of Glaucomatous Subjects Treated with Refractive Corneal Ablation Surgery

PURPOSE: To evaluate the clinical characteristics of newly diagnosed glaucomatous subjects who had a history of refractive corneal ablation surgery (RCAS). METHODS: Sixty-eight glaucomatous subjects who had a history of RCAS and 68 age- and visual field (VF) mean deviation-matched glaucomatous subjects with no history of RCAS were included. Intraocular pressure (IOP), central corneal thickness (CCT), VF, and retinal nerve fiber layer thickness determined by optical coherence tomography were assessed. Parameters were compared between patients with and without a history of RCAS. Between-eye comparisons in the same participant (more advanced vs. less-advanced eye, in terms of glaucoma severity) were performed in the RCAS group. RESULTS: With similar levels of glaucoma severity, those with a history of RCAS showed significantly lower baseline IOP and a thinner CCT than the eyes of individuals without a RCAS history (13.6 vs. 18.7 mmHg, 490.5 vs. 551.7 micrometer, all p < 0.001). However, the extent of IOP reduction after anti-glaucoma medication did not significantly differ between the two groups (17% vs. 24.3%, p = 0.144). In the between-eye comparisons of individual participants in the RCAS group, the more advanced eyes were more myopic than the less-advanced eyes (-1.84 vs. -0.58 diopter, p = 0.003). CONCLUSIONS: Eyes with a history of RCAS showed a similar level of IOP reduction as eyes without such a history after anti-glaucoma medication. Our finding that the more advanced eyes were more myopic than the less-advanced eyes in the same participant may suggest an association between glaucoma severity and myopic regression.

Clinical Characteristics of Glaucomatous Subjects Treated with Refractive Corneal Ablation Surgery

PURPOSE: To evaluate the clinical characteristics of newly diagnosed glaucomatous subjects who had a history of refractive corneal ablation surgery (RCAS). METHODS: Sixty-eight glaucomatous subjects who had a history of RCAS and 68 age- and visual field (VF) mean deviation-matched glaucomatous subjects with no history of RCAS were included. Intraocular pressure (IOP), central corneal thickness (CCT), VF, and retinal nerve fiber layer thickness determined by optical coherence tomography were assessed. Parameters were compared between patients with and without a history of RCAS. Between-eye comparisons in the same participant (more advanced vs. less-advanced eye, in terms of glaucoma severity) were performed in the RCAS group. RESULTS: With similar levels of glaucoma severity, those with a history of RCAS showed significantly lower baseline IOP and a thinner CCT than the eyes of individuals without a RCAS history (13.6 vs. 18.7 mmHg, 490.5 vs. 551.7 micrometer, all p < 0.001). However, the extent of IOP reduction after anti-glaucoma medication did not significantly differ between the two groups (17% vs. 24.3%, p = 0.144). In the between-eye comparisons of individual participants in the RCAS group, the more advanced eyes were more myopic than the less-advanced eyes (-1.84 vs. -0.58 diopter, p = 0.003). CONCLUSIONS: Eyes with a history of RCAS showed a similar level of IOP reduction as eyes without such a history after anti-glaucoma medication. Our finding that the more advanced eyes were more myopic than the less-advanced eyes in the same participant may suggest an association between glaucoma severity and myopic regression.

Increased Intraocular Pressure after Extensive Conjunctival Removal: A Case Report

A 50-year-old woman, who had undergone extensive removal of conjunctiva on the right eye for cosmetic purposes at a local clinic 8 months prior to presentation, was referred for uncontrolled intraocular pressure (IOP) elevation (up to 38 mmHg) despite maximal medical treatment. The superior and inferior conjunctival and episcleral vessels were severely engorged and the nasal and temporal bulbar conjunctival areas were covered with an avascular epithelium. Gonioscopic examination revealed an open angle with Schlemm's canal filled with blood to 360 degrees in the right eye. Brain and orbital magnetic resonance imaging and angiography results were normal. With the maximum tolerable anti-glaucoma medications, the IOP gradually decreased to 25 mmHg over 4 months of treatment. Extensive removal of conjunctiva and Tenon's capsule, leaving bare sclera, may lead to an elevation of the episcleral venous pressure because intrascleral and episcleral veins may no longer drain properly due to a lack of connection to Tenon's capsule and the conjunctival vasculature. This rare case suggests one possible mechanism of secondary glaucoma following ocular surgery.