ABSTRACT
Purpose: To evaluate the effectiveness of hyperbaric oxygen (HBO2) therapy as a treatment for central retinal artery occlusion (CRAO). Methods: A total of 38 patients who underwent HBO2 for non-arteritic CRAO were identified. Patients with arteritic CRAO, branch retinal artery occlusion, ophthalmic artery occlusion, and other diagnoses were excluded from the analysis. The main outcome measured was the change in visual acuity at the most recent follow-up exam compared to the visual acuity at presentation before the initiation of HBO2 therapy. Results: The overall visual acuity after HBO2 compared with the visual acuity at presentation showed a mean improvement of 0.5 logMAR from 2.2 to 1.7 logMAR (p=0.0003). Patients who presented with hand motion and light perception vision had a mean improvement of 0.4 logMAR (p=0.06) and 0.8 logMAR (p=0.004) after HBO2, respectively. An average visual acuity improvement of 0.5 logMAR (p=0.01) was observed when patients underwent HBO2 earlier than 24 hours of symptom onset. This mean improvement increased to 0.9 logMAR (p=0.009) if HBO2 was initiated within eight hours. Conclusions: HBO2 may be an effective treatment for non-arteritic CRAO, especially if patients are treated early and present with salvageable vision. The time to treatment and the presenting visual acuity may be predictive factors on the visual prognosis following HBO2. Further studies with a prospective design and more patients are necessary to determine the long-term outcomes and the optimal protocol for HBO2 in CRAO patients.
ABSTRACT
PURPOSE: To evaluate if off-label Age-Related Eye Disease Study 2 (AREDS2) supplementation prevents visual and anatomical deterioration in non-proliferative Idiopathic Macular Telangiectasia Type 2 (IMT2). PATIENTS AND METHODS: This is a single-center retrospective, comparative study of 82 IMT2 eyes treated with AREDS2 from January 1st, 2013 to January 1st, 2018. The study analysis consisted of a non-comparative arm, which included all AREDS2 eyes, and a comparative arm (27 AREDS2 and 42 untreated eyes) that only included eyes with complete follow-up data. Eyes were evaluated at baseline, 12 and 24 months. Better/worse eye sub-analysis was performed in the comparative study arm. Primary outcomes were best corrected visual acuity (BCVA) and optical coherence tomography (OCT) anatomical characteristics including largest cavitation diameter, central macular thickness (CMT), and length of ellipsoid zone (EZ) loss at 24 months. RESULTS: In the non-comparative arm, AREDS2 eyes showed stable BCVA (0.28 ± 0.18 logMAR at baseline vs 0.26 ± 0.19 logMAR at 24 months; p = 0.35) and OCT anatomical features after 24 months of supplementation. In the comparative arm, BCVA mean difference was greater for untreated eyes at 24 months (-0.09 ± 0.15 vs 0.03 ± 0.11 logMAR; p = <0.001). AREDS2 eyes had decreased cavitary diameter and EZ loss compared to untreated eyes at the study endpoint (p = 0.01 and p = 0.02, respectively). CMT remained stable for both cohorts throughout the study. For better/worse eye analysis, untreated eyes had worse BCVA at 24 months in both better and worse eyes (both p = 0.01). For anatomical outcomes, increases in both EZ loss (p = 0.04) and cavitary diameter (p = 0.001) among untreated eyes were only significant for eyes with worse baseline BCVA. CONCLUSION: Our results suggest that off-label AREDS2 supplementation in non-proliferative IMT2 may prevent anatomical and visual deterioration in a subset of eyes.
ABSTRACT
Many clinical trials have demonstrated the effectiveness of subthreshold phototherapy with no visible damage in retinal vascular diseases, such as diabetic retinopathy. We aimed primarily to investigate the effect of subthreshold diode micropulse laser (SDM) treatment on mouse retinal pigmented epithelium (RPE) cells. The expression of angiogenesis-modulating cytokines in response to SDM was also explored. The least toxic laser dose was selected by measuring cell viability with MTT assay and 5 % duty cycle (DC) was chosen for use in further experiments. RPE cells were treated with laser-induced radiation ranging from 0 to 400 mW for 24 h. The apoptotic rate of RPE cells was assessed by flow cytometry. Expressions of vascular endothelial growth factor A (VEGF-A), transforming growth factor beta (TGF-ß), basic fibroblast growth factor (bFGF), and pigment epithelium-derived factor (PEDF) were determined by Western Blotting and real-time PCR, respectively. After 24 h of laser irradiation, cell viability was reduced dose dependently and the effect was significant compared to the controls (P < 0.05). In addition, laser treatment with intensities of 100 and 200 mW with DC of 5 % produced no significant effect on cell viability and apoptosis as compared with the control group (P > 0.05). The protein and mRNA expressions of angiogenic stimulators (VEGF-A, TGF-ß, and bFGF) were significantly down-regulated (P < 0.05), whereas those of the angiogenic inhibitor (PEDF) were up-regulated (P < 0.05). No significant difference was found between the cells treated with different intensities of laser radiation (P > 0.05). Our results showed that SDM treatment of the RPE cells suppressed the expression of choroid neovasculization-promoting cytokines and up-regulated the angiogenic inhibitor, PEDF without damaging the cells. Further investigation is needed to understand the mechanism and to optimize the use of SDM as a novel method of treatment for retinal vascular diseases.