Photodynamic therapy for subfoveal choroidal neovascularization. A colour doppler study.

Purpose: To perform a color Doppler analysis of the effects on ocular blood flow of the photodynamic therapy (PDT) for subfoveal choroidal neovascularization (CNV) in age related macular degeneration (AMD). Methods: Ten patients aged from 64 to 78 (mean 72.4 yrs) with subfoveal CNV due to AMD were assessed in a mask fashion by color Doppler imaging (CDI) within 24 hours before, 1 week after and 2 months after undergoing PDT. All subjects were treated with verteporfirin at a drug dose of 6 mg/m2 body surface area and a light dose of 50 J/cm2. Patients included in the study underwent a CDI examination of the ophthalmic artery (OA) and posterior ciliary arteries (PCA’s) with an AU 580 Asynchronous-Hitachi analyser and a 7.5 MHz linear probe. A statistical analysis was made of the peak systolic velocity (PSV) and resistive index (RI) in the OA in the OA and PCA’s using the Student “t” test for paired data. Results: In the PCA’s there were no statiscally significant changes observed in the peak systolic velocity (PSV) and in resistive index (RI) at 1 week. After 2 months the PSV was 9.358+0.779 cm/sec vs 8.175+0.412 cm/sec (p<0.003) and the RI increase 0.687+0.028 vs 0.714+0.015 (p<0.008). There were no statistically significant differences in the OA blood flow indices at 1 week and 2 months after treatment. Conclusions: PDT is associated with decreased volumetric blood flow in the posterior ciliary arteries that supply the choroids two months after treatment. This study suggest that PDT could lead to alteration in choroidal blood flow and this appears to influence the visual outcome of the treatment.