Sir,

Multifocal choroiditis with panuveitis commonly occurs in middle-aged women. It is characterized by multiple punched out chorioretinal spots with vitritis.1 This disorder is complicated by the development of choroidal neovascularization (CNV) or progressive subretinal fibrosis. Subfoveal CNV is an important cause of severe visual loss2 in these patients. Methods of treating subfoveal CNV in multifocal choroiditis include observation (smaller than 100 μm),2 oral corticosteroids,3 thermal laser, surgical removal,4 and photodynamic therapy (PDT).5

Transpupillary thermotherapy (TTT) is an established modality of treatment for occult CNV.6 TTT for CNV in multifocal choroiditis has not been reported (Medline search).

We report a case of CNV secondary to multifocal choroiditis treated with pneumatic displacement of subretinal haemorrhage followed by TTT.

Case report

A 45-year-old male presented with an episode of diminished vision in the left eye of 15 days duration. A previous episode of decrease in vision in both eyes was followed by resolution of vision in the left eye only.

On examination, his best-corrected visual acuity was 1/60 in the right eye and 6/60; N36 at 20 cm in the left eye. Anterior segment examination was unremarkable. Fundus evaluation showed multiple chorioretinal atrophic scars in both eyes. One of the atrophic scars involved the fovea of the right eye. Subfoveal haemorrhage was noted in the fovea of the left eye (Figure 1a). Fundus fluorescein angiography (FFA) showed predominantly classic CNV with an indistinct temporal margin adjacent to a chorioretinal atrophy scar due to subretinal haemorrhage (Figure 1b). The subretinal haemorrhage was partially displaced with 0.5 ml of intravitreal air and prone positioning for 3 days (Figure 1c).

Figure 1
figure 1

(a) Shows subfoveal haemorrhage with multiple adjacent chorioretinal atrophic patches. (b) FFA showing hypofluorescence (arrow) due to subretinal haemorrhage. (c) Shows the displacement of subretinal haemorrhage after intravitreal air injection. (d) FFA showing disappearance of hypofluorescence (arrow) following displacement of subretinal haemorrhage by intravitreal air injection. (e) Shows scarred CNV 2 months following TTT. (f) FFA showing staining of the scarred CNV.

After 1 week, the patient's distant vision remained stable at 6/60 and near vision improved to N24 at 30 cm. FFA could now delineate the temporal margin of classic CNVM (Figure 1d). The options of PDT and TTT were discussed, and the patient chose to undergo TTT. TTT was delivered using an 810 nm diode laser (Iris Medical Oculight SLx, Iridex Corporation, Mountain View, CA, USA). The laser parameters were: power—130 mW; spot size—2 mm; duration—60 s. At 2 months post-treatment, his vision improved to 6/24, N10. Regression of CNVM was noted clinically (Figure 1e) and angiographically (Figure 1f). Vision and CNV remained stable 12 months following laser treatment.

Discussion

Choroidal neovascularization can occur in about 32% of patients with multifocal choroiditis.2 There are no proven methods of treating subfoveal CNV in this condition. The efficacy of treating classic CNVM with PDT has been established.7 PDT could be a good option in the treatment of CNV secondary to multifocal choroiditis as they are predominantly classic. Our patient opted for TTT due to the expense of PDT.

In our patient, subretinal haemorrhage obscured the temporal margin of CNV. Pneumatic displacement was attempted due to the short history. Intravitreal air was used because of its short half-life and since subretinal haemorrhage displacement could be noted within 2 days.8 Displacement allowed the temporal margin to be distinguished from the adjacent chorioretinal atrophic scar in our patient , thus helping us select a 2 mm spot size and avoiding an adjacent pigmented scar. Inclusion of the pigmented scar would have caused a non-homogenous reaction.9 Regressed CNV was noted clinically and angiographically at the end of 2 months and at the last follow-up at 12 months.

To conclude, TTT could be of value in the treatment of CNV in multifocal choroiditis. In case of associated subfoveal haemorrhage intravitreal air-aided displacement of the haemorrhage helps in clear delineation of the CNV.