Sir,

We read with interest the article ‘Gas tamponade combined with laser photocoagulation therapy for congenital optic disc pit maculopathy’.1 The study shows that combination therapy is a simple, effective, minimally invasive, and an economic alternative to vitreous surgery in management of optic disc pit maculopathy.

With the purpose of blocking inflow of fluid from optic pit to retinal layers, the laser-induced scar should extend from middle retinal layers to retinal pigment epithelium without damaging retinal nerve fiber layer.2 We have earlier reported the optical coherence tomography characteristics of optic pit maculopathy and had proposed the anatomical pathophysiology of fluid conduit from pit to macula. We showed that involvement of outer retinal layers is the first step in optic pit maculopathy, and from this layer, there could be bidirectional seepage: directly into subretinal space, through inner retinal schisis into subretinal space, or just into inner retinal layers, no involvement of subretinal space.3 Thus, it is prudent to establish adhesion between outer layers and RPE, creating inner layer adhesion is not required to stop the fluid movement. Diode laser having infrared wavelength can provide better adhesion between outer retina and RPE choroid at optic disc border in such scenario with minimal damage to nerve fiber layer in juxtapapillary area.

As the extent of detachment is confined to macular area, the rationale for extending laser treatment along superior and inferior margins of detached retina in the study is not clear. The laser treatment is usually performed placing 2–5 confluent rows in juxtapapillary area in circumferential extent.

As repeat treatment with gas tamponade and laser was required in 5 out of 9 eyes in the study, presence or absence of vitreous strands or glial tissue in optic pit on OCT scans would have been informative as these morphological patterns on OCT do better with surgical intervention along with peeling of such fibrous tissue.4

The study described the use of 66% C3F8 gas injection for tamponade, whereas previous reports have shown utilization of expansile pure gases in optic disc maculopathy.5 It is not clear how this mixture has any added benefit in optic disc maculopathy.