A 15-year-old Japanese boy with no medical history presented to our hospital with a chief complaint of decreased vision in his right eye for the past 6 months. At the initial examination, the best corrected visual acuity (BCVA) was 20/100 for the right eye and 20/16 for the left eye. No abnormalities were observed in intraocular pressure or in the anterior ocular segment findings. A fundus examination of the right eye revealed exudative retinal detachment with subretinal haemorrhage and orange-red lesion (arrow, Fig. 1a) from the upper intermediate periphery to the posterior pole (Fig. 1). Fluorescein angiography (Heidelberg Retina Angiography; Heidelberg Engineering, Heidelberg, Germany) revealed fluorescence leakage from the orange-red lesion (arrows, Fig. 1b). Abnormal telangiectatic vessels and microaneurysms were found at the nasal peripheral retina (arrowheads, Fig. 1b). Using B-mode ultrasonography, we observed elevation of the retina due to the haemorrhagic exudative retinal detachment, but no features of solid tumour, such as acoustic shadow, were present (arrow, Fig. 1c). The fundus of the left eye had no abnormal findings. No special findings were observed in the whole-body examination. Based on these findings, we diagnosed the case as Stage 3A Coats disease.
With the approval of the ethics committee of Okayama University Hospital, we treated the right eye with PDT. Before performing PDT, we explained the risks and benefits of the treatment to the patient and his parents and obtained written informed consent. PDT was performed according to the standard protocol treatment regimen [4,5,6]. Briefly, 6 mg/m2 of verteporfin (Visdyne, Novartis Ophthalmics AG, Basel, Switzerland) was administered intravenously, and 15 min later a 689 nm laser (Visulas 690S; Carl Zeiss Meditec Inc) was used to irradiate the haemorrhage for 83 s. The irradiation area had a diameter of 7200 μm, which was large enough to cover the entire subretinal haemorrhage.
Exudative retinal detachment was noted before PDT (Fig. 2a and d). At 1 month after treatment, the exudative changes had partially regressed (Fig. 2b and e). Although the subfoveal fluid had disappeared at 1 month after treatment, the ellipsoid zone (Ez) was discontinuous and BCVA was 20/200 (Fig. 2e). At 10 months after PDT, both the subretinal haemorrhage and the exudative retinal detachment had disappeared completely (Fig. 2c and f). Furthermore, the Ez was partially recovered (arrows, Fig. 2f) and BCVA had improved to 20/20.