Abstract
Abstract: :
Purpose: To assess imaging of subfoveal choroidal neovascularizations (CNV) undergoing photodynamic therapy (PDT) with the retinal thickness analyzer (RTA). Methods: Twenty-nine eyes of 29 consecutive patients with predominantly classical, subfoveal CNV due to age related macular degeneration eligible for PDT treatment according to the TAP-criteria underwent conventional fluorescein angiography (FA) and RTA scanning. The FA dimensions of the CNV (maximum diameter) were assessed independently by 2 masked graders. With the RTA the amount of intra-retinal edema overlying the CNV was measured in the retinal thickness map and the size of significant retinal thickening determined. Additionally the size of the CNV (maximum diameter) was assessed on slit-images of the RTA in a masked manner. Results: Pearson correlation of grading angiograms was high (r=0.918, p<0.001) between the graders. The mean diameter of the CNV on FA was 2.3 (SD 1.1)mm. On RTA mean maximum retinal thickness over the CNV was 373 (SD 93)um. The significantly thickened retinal area showed a mean diameter of 3.0 (SD 1.2)mm. Mean diameter of CNV determined from RTA images was 2.5 (SD 1.0)mm and correlated highly with measurements obtained by FA (r=0.91, p<0.001). The thickened retinal area on RTA correlated well with the size of CNV on FA (r=0.65, p<0.001), but peak retinal thickness over CNV measured on RTA did not correlate with the size of CNV(r=0.1, p=0.586). Conclusions: The RTA allows an objective and quantitative imaging of pathological findings in predominantly classical CNV. It shows high correlation with the assessment by FA and might therefore be helpful in monitoring the therapeutic effects of PDT and simplify the follow-up.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, S • photodynamic therapy • choroid: neovascularization