Purpose: To explore the potential use of photodynamic therapy for recalcitrant cystoid macular oedema (CMO) refractory to standard treatments in vasculopathies of the retinal circulation.

Methods: Retrospective case review of patients with chronic CMO due to various vasculopathies of the inner retinal circulation for whom maximal conventional therapies had failed and who underwent the combination therapy of photodynamic therapy (PDT), intravitreal anti-vascular endothelial growth factor and intravitreal steroid. Clinical assessment, visual acuity, optical coherence tomography and central macular thickness measurements were acquired for three visits prior to PDT and three visits post PDT to evaluate the activity of CMO.

Results: Four patients (six eyes) were included in this series. CMO was due to diabetic retinopathy in two patients, and branch retinal vein occlusion in two patients. Multiple intravitreal steroid and anti-vascular endothelial growth factor injections had been trialled in all patients, two patients had undergone micropulse macular laser and three patients had undergone vitrectomy with epiretinal membrane peel, without resolution of CMO. The inactivity of CMO (full and partial) was seen in all patients as determined by optical coherence tomography. Best corrected visual acuity improved in three patients (mean: 0.46 logMAR units). One patient experienced a decline in best corrected visual acuity despite bilateral PDT (mean: 0.57 logMAR units). Central macular thickness reduced in all cases (mean: 128 microns).

Conclusions: There is a potential role of photodynamic therapy in managing recalcitrant cystoid macular oedema secondary to inner retinal vasculopathies, despite being an older therapy originally devised for use in choroidal and sub-retinal vasculopathies.