Purpose:
To determine changes in retinal neurosensory structure after the first anti-VEGF injection in central retinal vein occlusion (CRVO), by using spectral domain coherence tomography (SD-OCT).
Methods:
Consecutive patients with newly diagnosed macular edema secondary to CRVO treated with intravitreal ranibizumab or bevacizumab were included in this study. SD-OCT images were aquired at baseline and 4 weeks after the initial injection. We qualitatively determined the number and the changes of small dense particles (SDPs) within the neurosensory layers of the foveal and parafoveal region. Objective changes of best corrected visual acuity (BCVA) were measured with ETDRS reading charts.
Results:
Fifty-one eyes of 51 patients were included. 47% (n=24) were treated with intravitreal bevacizumab whereas 53% (n=27) received intravitreal ranibizumab. At baseline a variable amout of SDPs could be observed in all eyes. The number of SDPs declined in 65% after treatment (29% stable, 6% higher). The decline in SDPs was positively correlated with a reduction of central retinal thickness (p=0.001) and visible subretinal fluid amount in SD-OCT (p=0.002). There was no significant correlation with the overall improvement of best corrected visual acuity (BCVA) (p=0.160) but in cases of angiographically profen nonischemic CRVO (n = 31) we found a positive correlation (p=0.000). No significant difference was found in the ranibizumab or bevacizumab subgroup.
Conclusions:
SDPs are a newly reported SD-OCT finding in patients with CRVO. Their reduction after VEGF therapy was highly correlated with the improvement of central retinal thickness and the fall of subretinal fluid. A positive correlation to a visual recovery was found only in the nonischemic subgroup. The results suggests that SDPs may be used as an additional prognostic and monitoring tool in patients with macular edema in CRVO.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • vascular occlusion/vascular occlusive disease • retina