Evaluating role of bone marrow-derived stem cells in dry age-related macular degeneration using multifocal electroretinogram and fundus autofluorescence imaging.

AIM: To evaluate the role of bone marrow-derived stem cells in the treatment of advanced dry age-related macular degeneration (AMD) using multifocal electroretinogram (mf-ERG) and fundus autofluorescence imaging. METHODS: Thirty patients (60 eyes) with bilateral central geographic atrophy (GA) were recruited. Worse eye of each patient received autologous bone marrow-derived hematopoietic stem cells (BM-HSCs) (group 1) and the fellow eye with better visual acuity served as control (group 2). The effect of stem cell therapy was determined in terms of visual acuity, amplitude and implicit time in mf-ERG and size of GA on fundus autofluorescence imaging. These tests were performed at presentation and first, third and sixth month follow up. Adverse events (if any) were also monitored. RESULTS: At 6mo follow-up there was no statistically significant improvement in median logMAR best corrected visual acuity (BCVA) in either group. Mf-ERG revealed significant improvement in amplitude and implicit time in the intervention group. A significant decrease was also noted in greatest linear dimension (GLD) of GA in the eyes receiving stem cells [6.78±2.60 mm at baseline to 6.56±2.59 mm at 6mo (P=0.021)]. However, no such improvement was noted in the control group. CONCLUSION: Electrophysiological and anatomical improvement in the intervention group sheds light on the therapeutic role of BM-HSCs. Further studies are required to determine the stage of disease at which the maximal benefit can be achieved and to standardize the dose and frequency of stem cell injection.

Müller stem cell dependent retinal regeneration.

Müller Stem cells to treat ocular diseases has triggered enthusiasm across all medical and scientific communities. Recent development in the field of stem cells has widened the prospects of applying cell based therapies to regenerate ocular tissues that have been irreversibly damaged by disease or injury. Ocular tissues such as the lens and the retina are now known to possess cell having remarkable regenerative abilities. Recent studies have shown that the Müller glia, a cell found in all vertebrate retinas, is the primary source of new neurons, and therefore are considered as the cellular basis for retinal regeneration in mammalian retinas. Here, we review the current status of retinal regeneration of the human eye by Müller stem cells. This review elucidates the current status of retinal regeneration by Müller stem cells, along with major retinal degenerative diseases where these stem cells play regenerative role in retinal repair and replacement.

Efficacy of oral valproic acid in patients with retinitis pigmentosa.

PURPOSE: To evaluate the efficacy of valproic acid (VPA) on visual function in patients with retinitis pigmentosa (RP). METHODS: Thirty patients (60 eyes) with typical RP were recruited for the study. Of these, 15 patients received oral VPA (500 mg once daily) for a period of 1 year (group 1) and the remaining 15 received no treatment (group 2) and served as controls. The effect of VPA on visual function was determined in terms of visual acuity, amplitude and implicit time in multifocal electroretinography (mfERG), and visual evoked response (VER) performed at presentation and at the third month, sixth month, and 1 year in both groups. Side effects of oral VPA were also monitored. RESULTS: At 1-year follow-up, 14 of 15 patients in group 1 had improvement in median best corrected visual acuity (BCVA) from 1.8 [Range (R) 1-3] at baseline to 1.3 (R, 0.6-1.3) (P<0.001). In contrast, there was a slight decrease in median BCVA from 1.8 (0.8- 3) logarithm of the minimum angle of resolution (logMAR) at baseline to 1.83 (P=0.3) in the control arm. There was also a statistically significant increase in improvement in amplitude and latency/implicit time in mfERG and VER in this group (P<0.001). However, no such improvement was observed in the control arm. CONCLUSIONS: Thus, VPA seems to have a positive effect on the visual functions in RP patients. Long-term studies evaluating the dose modifications, genetic analysis, and change in visual fields will add to our current knowledge.