Optical coherence tomography to monitor photodynamic therapy in pathological myopia

Abstract

Aim: To evaluate the role of optical coherence tomography (OCT) in determining choroidal neovascularisation (CNV) activity before and after photodynamic therapy (PDT) in patients with pathological myopia.

Methods: 33 patients (33 eyes) with pathological myopia and being treated with PDT were included. Every 3 months all patients were evaluated and presence or absence of leakage on fluorescein angiography, presence of intraretinal or subretinal fluid on OCT, and macular and choroidal neovascular complex thickness on OCT, were determined at each examination.

Results: The macular thickness decreased significantly after PDT at 6 months (p = 0.001) and at 12 months follow up (p = 0.01). However, no significant changes in CNV thickness were measured after PDT at 6 months of follow up (p = 0.418) and at 12 months of follow up (p = 0.521). Once the diagnosis of CNV associated with pathological myopia was established, before treatment, OCT had a sensitivity of 96.96% for detecting CNV activity. After treatment, OCT had a good sensitivity (95.23%) and a moderate specificity (69,69%) in determining CNV activity, which resulted in a diagnostic efficiency (proportion of correct results) of 79.62%.

Conclusions: OCT appears to be useful for indicating CNV activity. Therefore, it may serve as a complementary technique for deciding the need for PDT and re-treatment in patients with pathological myopia.