Surface-Based Analyses of Anatomical Properties of the Visual Cortex in Macular Degeneration

INTRODUCTION: Macular degeneration (MD) can cause a central visual field defect. In a previous study, we found volumetric reductions along the entire visual pathways of MD patients, possibly indicating degeneration of inactive neuronal tissue. This may have important implications. In particular, new therapeutic strategies to restore retinal function rely on intact visual pathways and cortex to reestablish visual function. Here we reanalyze the data of our previous study using surface-based morphometry (SBM) rather than voxel-based morphometry (VBM). This can help determine the robustness of the findings and will lead to a better understanding of the nature of neuroanatomical changes associated with MD. METHODS: The metrics of interest were acquired by performing SBM analysis on T1-weighted MRI data acquired from 113 subjects: patients with juvenile MD (JMD; n = 34), patients with age-related MD (AMD; n = 24) and healthy age-matched controls (HC; n = 55). RESULTS: Relative to age-matched controls, JMD patients showed a thinner cortex, a smaller cortical surface area and a lower grey matter volume in V1 and V2, while AMD patients showed thinning of the cortex in V2. Neither patient group showed a significant difference in mean curvature of the visual cortex. DISCUSSION: The thinner cortex, smaller surface area and lower grey matter volume in the visual cortex of JMD patients are consistent with our previous results showing a volumetric reduction in their visual cortex. Finding comparable results using two rather different analysis techniques suggests the presence of marked cortical degeneration in the JMD patients. In the AMD patients, we found a thinner cortex in V2 but not in V1. In contrast to our previous VBM analysis, SBM revealed no volumetric reductions of the visual cortex. This suggests that the cortical changes in AMD patients are relatively subtle, as they apparently can be missed by one of the methods

Prospective, Randomized Intervention Study Comparing Retinal Pigment Epithelium-Choroid Graft Surgery and Anti-VEGF Therapy in Patients with Exudative Age-Related Macular Degeneration

Purpose: To investigate whether patients with exudative age-related macular degeneration and a submacular hemorrhage, retinal pigment epithelium (RPE) tear or nonresponders to anti-vascular endothelial growth factor (VEGF) benefit more from a free RPE-choroid graft transplantation surgery than from (continuation of) anti-VEGF treatment. Procedures: A total of 20 patients were included in this prospective, international, multicenter, randomized intervention study. Results: The change in the mean number of Early Treatment of Diabetic Retinopathy Study (ETDRS) letters in the graft group 1 year postoperatively was -15 (range -54 to +26), whilst 2 patients experienced a gain of >10 letters. The median preoperative visual acuity (VA) was 0.75 logMAR (range 0.46-2.8), and the mean postoperative VA was 1.48 logMAR (range 0.14-2.8). The change in the mean number of ETDRS letters in the anti-VEGF group was -8 (range -26 to +6); no patients experienced a >10 letter gain. The median preoperative VA was 1.36 logMAR (range 0.58-1.6), and the median postoperative VA was 1.42 logMAR (range 0.44-1.66). Conclusions: The included patient group is far too small to draw conclusions. However, both gain and loss of VA may be experienced by patients undergoing either treatment method; more gain might be possible for patients with a graft in the absence of complications. (C) 2015 S. Karger AG, Base

INTRAVITREAL VERSUS SUBRETINAL ADMINISTRATION OF RECOMBINANT TISSUE PLASMINOGEN ACTIVATOR COMBINED WITH GAS FOR ACUTE SUBMACULAR HEMORRHAGES DUE TO AGE-RELATED MACULAR DEGENERATION An Exploratory Prospective Study

Purpose: Current management of submacular hemorrhage (SMH) favors vitrectomy and gas with subretinal administration of recombinant tissue plasminogen activator (rtPA) over mere intravitreal rtPA injections and gas. In this study, we aimed to compare the effectiveness of both treatment modalities to displace submacular blood. Methods: Twenty-four patients with SMH secondary to age-related macular degeneration were included. The SMH had to exist <= 14 days at time of surgery and SMH thickness had to be between 250 mu m and 1,250 mu m. Patients were randomized to either intravitreal injections of rtPA, perfluoropropane (C3F8) gas, and bevacizumab (n = 12) or vitrectomy with subretinal rtPA administration, intravitreal C3F8 gas, and bevacizumab (n = 12). The SMH volume change was measured on spectral domain optical coherence tomography postoperatively within a 2.5-mm cylinder centered at the fovea. Results: Median relative volume reduction of subretinal blood at 6 weeks postoperatively was 97% (95% confidence interval: 91-99%) in the intravitreal rtPA group and 100% (95-100%) in the subretinal rtPA group and did not differ significantly between groups (P = 0.56). Conclusion: Both treatment modalities effectively displaced SMH in this exploratory clinical trial. To more definitely study the noninferiority of intravitreal rtPA with gas to subretinal rtPA, vitrectomy with gas, a larger clinical trial would be necessary