Background/aims To determine the frequency and cause of visual loss following intra-arterial melphalan (IAM) in patients with retinoblastoma with age appropriate vision.

Methods Assessment of patients with refractory retinoblastoma that had undergone systemic chemotherapy, with or without local treatment, and were subsequently treated with IAM. Eyes of patients with a healthy foveola were assessed. The main outcome measures included visual, macular (including Pattern Visual Evoked Potentials and Fundus Fluorescein Angiography) and retinal functions (Electroretinograms).

Results Five of twelve eyes (42%) demonstrated severe visual loss following IAM at last follow-up (median 21 months). This was due to either retinal detachment (1 eye, 20%) or choroidal ischaemia involving the foveola (4 eyes, 80%). All 3 eyes that had technical difficulties or vasospasm during catheterisation suffered visual loss. 8 out of 10 eyes that had a non-age adjusted dose of melphalan suffered visual loss. Electroretinograms post-IAM deteriorated in 4 of 8 eyes (50%) and Pattern Visual Evoked Potentials deteriorated in 3 (37%), though only one of these 3 showed concomitant visual acuity loss.

Conclusions Structural and vascular damage to the foveola limited visual acuity. Complications associated with catheterisation and high doses of melphalan may be contributory factors to visual morbidity. Although visual loss is described, no patient developed metastases and most retained good vision.