Application of Optical Coherent Tomography in monitoring age-related macular degeneration after photodynamic therapy

Introduction
Of our study is to check usefulness of OCT exam in qualification for PDT, and as independent diagnostic tool. OCT exam gives quantification of parameters for monitoring PDT. Correlation between the results of OCT exams and visual acuity was estimated as well as the prognosis of PDT efficacy on the basis of results from OCT exams.

Material and methods
59 eyes of 56 patients with CNV caused by AMD were examined and treated PDT. OCT and BCVA examination were done before PDT, 1 week, 4 weeks and 12 weeks after PDT. OCT measurement: minimal retinal thickness in fovea, average retinal thickness in fovea, retinal volume in fovea and total retinal volume in macula. STRATUS OCT 3000 with soft. v.4.0.2 (0056) was used. All 59 eyes form group D. The eyes were divided into two antagonist subgroup: D1 – 38 eyes with visual acuity stabilization or worsening and D2 – 21 eyes with visual acuity improvement 12 weeks after PDT.

Results
There was correlation between results in exams of retinal thickness and volume in macula. Group D has significant decrease of minimal retinal thickness, average retinal thickness in fovea and retinal volume in fovea 4 weeks after PDT. In subgroup D1 there was statistically significant decrease of minimal retinal thickness and total retinal volume in macula, 12 weeks after PDT. There was in subgroup D1 positive correlation between relative changes of total retinal volume in macula and relative changes of BCVA four weeks after PDT.

Conclusions
OCT exam is very useful in qualification for PDT, but it could not be an independent diagnostic tool. Useful quantification of parameters in OCT exam are retinal thickness and retinal volume. OCT does not allow to prognosis efficacy of PDT.