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AIM: To evaluate the influence of optic disc size on the diagnostic accuracy of macular ganglion cell complex (GCC) and conventional peripapillary retinal nerve fiber layer (pRNFL) analyses provided by spectral domain optical coherence tomography (SD-OCT) in glaucoma. METHODS: Eighty-two glaucoma patients and 30 healthy subjects were included. All patients underwent GCC (7 × 7 mm macular grid, consisting of RNFL, ganglion cell and inner plexiform layers) and pRNFL thickness measurement (3.45 mm circular scan) by SD-OCT. One eye was randomly selected for analysis. Initially, receiver operating characteristic (ROC) curves were generated for different GCC and pRNFL parameters. The effect of disc area on the diagnostic accuracy of these parameters was evaluated using a logistic ROC regression model. Subsequently, 1.5, 2.0, and 2.5 mm(2) disc sizes were arbitrarily chosen (based on data distribution) and the predicted areas under the ROC curves (AUCs) and sensitivities were compared at fixed specificities for each. RESULTS: Average mean deviation index for glaucomatous eyes was -5.3 ± 5.2 dB. Similar AUCs were found for the best pRNFL (average thickness = 0.872) and GCC parameters (average thickness = 0.824; P = 0.19). The coefficient representing disc area in the ROC regression model was not statistically significant for average pRNFL thickness (-0.176) or average GCC thickness (0.088; P ≥ 0.56). AUCs for fixed disc areas (1.5, 2.0, and 2.5 mm(2)) were 0.904, 0.891, and 0.875 for average pRNFL thickness and 0.834, 0.842, and 0.851 for average GCC thickness, respectively. The highest sensitivities - at 80% specificity for average pRNFL (84.5%) and GCC thicknesses (74.5%) - were found with disc sizes fixed at 1.5 mm(2) and 2.5 mm(2). CONCLUSION: Diagnostic accuracy was similar between pRNFL and GCC thickness parameters. Although not statistically significant, there was a trend for a better diagnostic accuracy of pRNFL thickness measurement in cases of smaller discs. For GCC analysis, an inverse effect was observed.

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PURPOSE: To investigate the relationship between spectral domain optical coherence tomography (SD-OCT) findings and visual outcomes following resolution of macular edema in central retinal vein occlusion (CRVO). METHODS: Patients with recent onset CRVO who had undergone SD-OCT and fluorescein angiography (FA) exams on the day of initial presentation were included. All patients had resolution of macular edema in SD-OCT images at the end of follow-up, and they were separated into two groups according to final visual acuity: group 1 (≤20/200) and group 2 (>20/200). SD-OCT scans and FA studies were analyzed in a masked fashion. Macular perfusion status by FA was categorized according to presence or absence of macular ischemia. RESULTS: A total of 22 eyes from 22 patients [mean age 53.0 ± 15.0 (standard deviation)] were included. Mean follow up period was 14.6 ± 8.1 (standard deviation) months. Group 1 (10 eyes) had significantly higher rates of residual intraretinal fluid, loss of foveal inner segment/outer segment (IS/OS) junction line and loss of inner retinal layers in late stage SD-OCT images (P = 0.027) when compared with group 2 (12 eyes). Loss of foveal IS/OS junction line (odds ratio [OR] = 13.826; P = 0.098) and loss of inner retinal layers (OR = 38.908; P = 0.013) in late stage SD-OCT images were correlated with poorer final visual outcomes. Macular ischemia by FA correlated with thinner central subfield thickness (r = -0.54, P = 0.021) and loss of inner retinal layers (r = 0.47, P = 0.031) in early stage SD-OCT images; and presence of residual intraretinal fluid (r = 0.61, P = 0.003) and loss of inner retinal layers (r = 0.71, P < 0.001) in late stage SD-OCT images. CONCLUSION: Loss of foveal IS/OS junction line and inner retinal layers on SD-OCT significantly correlated with poorer visual outcomes in CRVO patients.

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PURPOSE: To investigate macular changes in eyes with postoperative hypotony without clinical maculopathy using high-resolution Fourier-domain optical coherence tomography (FD-OCT). METHODS: Fourteen eyes of 12 patients with postoperative intraocular pressure (IOP) ï¿¡ 6 mmHg for at least 4 weeks but with no detectable clinical features associated with hypotony maculopathy were imaged by FD-OCT prospectively. Images were analysed by two retina specialists masked to clinical findings. RESULTS: Most patients were female (83%) and myopic (75%) with a mean age of 65 ± 17 [standard deviation (SD)] years (range 2­86 years). Mean central corneal thickness was 519 ± 34 lm [95% confidence interval (CI) 502­537] and mean IOP before surgery was 20 ± 8 mmHg (95% CI 15­24). During the period of hypotony (mean 15 ± 6 weeks), the average mean IOP was 4 ± 1 mmHg (95% CI 3­5). Abnormal FD-OCT findings (retinal folds and / or intraretinal fluid) were present in eight eyes. These patients had a higher rate of visual symptoms (75% versus 17%), visual acuity loss (‡ 2 lines; 63% versus 17%) and increased mean foveal thickness (250 ± 26 versus 210 ± 12 lm; p < 0.01, Mann­Whitney U-test) compared with those with normal FD-OCT. CONCLUSION: FD-OCT identified subclinical macular abnormalities in over half of the eyes with postoperative hypotony. These findings were accompanied by visual disturbances and central macular thickening. FD-OCT can be an important diagnostic tool for this disorder when clinical features are absent.

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BACKGROUND AND OBJECTIVE: To assess anatomic and visual outcomes after pars plana vitrectomy for vitreomacular traction syndrome. PATIENTS AND METHODS: Charts of 746 patients who had vitrectomy surgery with membrane peel between January 2002 and December 2007 were reviewed. Vitreomacular traction syndrome (VMT) was diagnosed based on optical coherence tomography (OCT) appearance. Twenty eyes of 20 patients were found to have had vitrectomy surgery for VMT and were included in the study. RESULTS: Mean visual acuity was 20/122 preoperatively and 20/68 postoperatively (P = .005). Mean foveal thickness was 404.00 microm preoperatively and 250.55 microm postoperatively (P = .001). A subgroup analysis was performed based on preoperative OCT appearance. Improvement in vision was not significant in eyes with lamellar separation between the inner and outer fovea (P = .379), but was significant in eyes with cystoid macular edema (P = .045) or perifoveal traction (P = .040). CONCLUSION: Overall, there was a significant improvement in visual acuity and central foveal thickness postoperatively. Eyes with lamellar separation of the inner and outer foveal layers preoperatively had worse visual results, whereas eyes with cystoid macular edema or perifoveal VMT had better visual results.

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BACKGROUND AND OBJECTIVE: To assess anatomic and visual outcomes after pars plana vitrectomy for lamellar macular holes. PATIENTS AND METHODS: Charts of 746 patients who had vitrectomy surgery with membrane peel were reviewed. Preoperative diagnosis of lamellar macular hole was based on optical coherence tomography (OCT) appearance; 16 eyes of 16 patients met the inclusion criteria. RESULTS: Mean acuity was 20/158 preoperatively and 20/118 postoperatively (P = .408). Central macular thickness was 377.06 µm preoperatively and 245.7 µm postoperatively (P = .002). Two eyes (13%) developed full-thickness macular holes postoperatively. Six eyes (38%) continued to have a lamellar macular defect on OCT postoperatively. CONCLUSION: Despite postoperative anatomic improvement in many patients and an overall decrease in foveal thickness on OCT, this retrospective series suggests that vitrectomy for lamellar holes may not improve visual acuity.

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One patient with past ocular history of full thickness macular hole surgically closed in the right eye was followed with diagnostic of lamellar macular hole in the left eye since 2000. After uncomplicated cataract surgery in the left eye in March 2008, the lamellar hole spontaneously progressed to full thickness macular hole. The patient underwent pars plana vitrectomy, membrane peel and gas bubble injection, with successful closure of the macular hole and improvement in the visual acuity. Optical coherence tomography (OCT) scans through the macula were performed at the initial and follow-up visits. To the best of our knowledge, this is the first description of a long-standing stable lamellar macular hole progressing into a full thickness macular hole. The causative factors for this progression remain unclear.

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Two patients presented complaints of visual acuity worsening in one eye. During examination they showed optical coherence tomography (OCT) and clinical findings indistingishable from myopic foveoschisis, although both had minimal refractive errors. One of the patients was followed without surgery until the disease progressed and the visual acuity decreased. The second patient presented with lamellar macular hole associated with the foveoschisis. Both patients underwent pars plana vitrectomy with pre-retinal membranes peeling and intra-vitreal gas infusion and both developed full-thickness macular hole after surgery. The second patient underwent a second surgery with peeling of the internal limiting membrane (ILM) and with successful macular hole closure. OCT was performed at the initial and follow-up visits. In conclusion, foveoschisis may develop in eyes without high myopia. The causative factors, OCT findings and surgical outcomes are very similar to myopic foveoschisis.

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PURPOSE. To investigate the characteristics of a spectral-domain optical coherence tomography (SD-OCT) image phenomenon known as the mirror artifact, calculate its prevalence, analyze potential risk factors, measure severity, and correlate it to spherical equivalent and central visual acuity (VA). METHODS. OCT macular cube 512 x 128 scans taken between January 2008 and February 2009 at the New England Eye Center were analyzed for the presence of mirror artifacts. Artifact severity was determined by the degree of segmentation breakdown that it caused on the macular map. A retrospective review was conducted of the medical records of patients with artifacts and of a random control group without artifacts. RESULTS. Of 1592 patients, 9.3% (148 patients, 200 eyes) had scans that contained mirror artifacts. A significantly more myopic spherical equivalent (P < 0.001), worse VA (P < 0.001), longer axial lengths (P = 0.004), and higher proportions of moderate to high myopia (P < 0.001) were found in patients with mirror artifacts than in patients without artifacts. Worse VA was associated with increased artifact severity (P = 0.04). CONCLUSIONS. In all scans analyzed, a high prevalence of mirror artifacts was found. This image artifact was often associated with patients with moderate to high myopia. Improvements in instrumentation may be necessary to resolve this problem in moderately and highly myopic eyes. Operators should be advised to properly position the retina when scanning eyes. In cases in which peripheral abnormalities in topographic measurements of retinal thickness are found, corresponding OCT scans should be examined for the presence of mirror artifacts.

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