Name

Fossette colobomateuse associé à une maculopathie : caractéristiques tomographiques

The purpose is to study the Swept Source optical coherence tomography (SS-OCT) characteristics of optic disc pit with maculopathy(ODP-M) and to discuss the mechanism of fluid passage from the optic disc pit to the macula.

A 6 years old child presented with progressive bilateral loss of vision. The best-corrected visual acuity was 1/10 in the right eye and 6/10 in the left eye. Fundus examination showed bilateral optic disc pit associated with serous macular detachment. The rest of the examination was unremarkable. SS-OCT was performed. 

SS-OCT revealed the presence of hyporeflective spaces below the optic disc, a hyperreflective fibroglial tissue, and vitreous strands were observed spanning over the optic disc. It also detected a communication between the perineural and subretinal space at the margin of the optic disc. 

Three-dimensional SS-OCT revealed the morphology of the optic disc pit associated maculopathy. Horizontal sections through the macula showed outer layer retinoschisis (OLR) with inner layer retinoschisis (ILR) and serous macular detachment that affect both eyes. A communication between the OLR and the SMD through a dehiscence of the external retina was detected in the right eye. 

Optic disc pit is a rare congenital anomaly of the optic disc, which can be complicated by a maculopathy associated with progressive visual loss. The mechanism of pathogenesis of ODP-M has not been fully elucidated, several competing theories have suggested it may be vitreous fluid, cerebrospinal fluid, leakage from blood vessels at the base of the pit or leakage from the choroid.  

SS-OCT is a noninvasive tool for diagnosing optic nerve head pit between the perineural and subretinal space at the margin of the optic disc. It also shows the fluid distribution in the associated maculopathy. This supports the hypothesis that cerebrospinal fluid could be the source of fluid in optic disc pit maculopathy.