Purpose
The purpose of this study was to analyze the spectral domain optical coherent topography (SD-OCT) predictive factors for best-corrected visual acuity (BCVA) after dexamethasone (700 mcg) intravitreal implant (Ozurdex), in patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO).
Methods
This prospective study enrolled patients with ME secondary to CRVO and BRVO. BCVA, bio-microscopy, intraocular pressure, fundus photography and SD-OCT were performed at baseline and at 8 weeks after Ozurdex injection. Fundus fluorescein angiography was performed at baseline. SD-OCT was analyzed for integrity of the external limiting membrane (ELM), photoreceptor inner segments (IS), and outer segments (OS) zone.
Results
Forty six patients; 21 with CRVO and 25 with BRVO were treated with Ozurdex and completed their 8 week check. 5 patients from the CRVO group were excluded (1 patient had endopthalmitis and missed the 8 week check, 3 had incomplete documentation, 1 was previously treated with Avastin). 7 patients from the BRVO group were excluded (6 incomplete documentation, 1 was treated with Ozurdex previously). Twenty nine eyes of 29 patients were analyzed. 14 patients (9 male, 5 female) had CRVO and 15 patients (8 male, 7 female) had BRVO. The ELM was intact in 50% of patients with CRVO and 60% of the BRVO patients. Disturbed ELM was accompanied by a focal disintegration of IS/OS zone. Two patients developed raised intraocular pressure (over 25 mmHg), with one persisting over 6 months. Table of Results:
Conclusions
The integrity of the outer retinal areas seems to be an important predictor in the BCVA outcome in patients. It is necessary to look at morphological findings when considering treating and re-treating patients with vein occlusions. A majority of patients had poor visual acuity at start of treatment in our study; this was likely due to long duration of vein occlusion prior to Ozurdex therapy. We expect patients in our next cohort to have better visual outcomes, with reduction of waiting times for treatment. A further study on larger patient numbers is ongoing.
Keywords: 498 diabetes •
688 retina