Subretinal pigment dispersion following transpupillary thermotherapy for choroidal melanoma

Purpose: To report the case of a patient who developed considerable subretinal pigment/debris dispersion following transpupillary thermotherapy (TTT). This type of tumour response is extremely rare with this relatively new therapeutic modality. Methods: A 50-year-old man with a left juxtapapillary choroidal melanoma measuring 8 x 6 x 4.3 mm was treated with 810 nm diode laser TTT administered in two sessions. Spot size was 3 mm and the power setting was 450 mW. Results: Four months after the first treatment session, a considerable amount of pigment/debris was seen to have dispersed in the subretinal space, accumulating mainly in the macular area. Over a 12-month follow-up, the tumour showed progressive shrinkage without any change in the amount or location of the shed pigment/debris. No new tumour formation, recurrence or systemic metastases were detected. Conclusion: Subretinal pigment/debris dispersion is an unusual complication after TTT and requires close follow-up. There has been no short-term compromise on the life or visual acuity of this patient.