Abstract
Purpose :
To measure the aqueous levels of vascular endothelial growth factor (VEGF) before and after treatment with anti-VEGF agents in patients with cystic macular edema (CME) due to retinal vein occlusion (RVO) and correlate with the central macular thickness (CMT) using OCT at the time of each treatment
Methods :
The study included all patients with CME due to central RVO (CRVO) and branch RVO (BRVO) who underwent treatment with one of the anti-VEGF agents with a minimum of 2 injections. At each injection, paracentesis was performed to equalize the intraocular pressure and the sample of aqueous thus obtained was stored in the lab in -800 C freezer. For controls, aqueous collected from patients undergoing cataract extraction, without any other retinal pathology were included. At the time of analysis, aqueous samples were thawed at room temperature and VEGF level (pg/ml) was measured using human premixed multi-analyte kit on Luminex MAGPIX analyzer (Austin, TX, USA). Spectral-domain OCT was obtained at each visit before the injection and CMT was measured.
For analysis, only those samples were considered for analyses where it was continuously collected without a gap of more than 3 months – if there was a gap, they were counted as a different session. The VEGF levels and the CMT measurements obtained at the time of the most recent injection were compared to the baseline levels, respectively. The VEGF levels in all samples were also compared with CMT.
Results :
103 samples from 29 sessions in 20 patients with CME were included in the study [CRVO (n=6) and BRVO 9n=14)]. The average VEGF level at baseline was 121.3 pg/ml and at the most recent injection, 21.9 pg/ml (p<0.001). For controls (n=97), the mean VEGF level was 31.7 pg/ml. The average CMT at baseline was 505µm and at the most recent injection, 281µm (p<0.0001). Further, a significant correlation was found between VEGF levels and CMT (p<0.0001)
Conclusions :
Aqueous levels of VEGF can be easily measured at every injection in patients with CME due to vein occlusion. Aqueous levels of VEGF were significantly reduced after treatment with anti-VEGF agents. With the ease of obtaining the aqueous sample and measuring the VEGF levels, this may be a useful parameter in the future, in addition to visual acuity and retinal thickness, to possibly personalize the treatment of patients with CME secondary to vein occlusion.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.