Pictorial CME
 
Eccentric Macular Hole and Inner Retinal Dimpling Following Pars Plana Vitrectomy
 
Srikanta Kumar Padhy, Vinod Kumar, Raghav Ravani
Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India


Corresponding Author
:
Vinod Kumar 
MD, FRCS
Assistant Professor, 
Department of Ophthalmology, 
Dr R.P.Center for ophthalmic sciences, AIIMS, New Delhi-110029, India
Email id: drvinod_agg@yahoo.com


Abstract

An elderly male was seen following vitrectomy and internal limiting membrane peeling for macular hole. Multimodal imaging revealed an eccentric macular hole, inner retinal dimpling and signs of trauma on the macular surface. These potential complications of inner limiting membrane peeling are demonstrated.

A 59-years-old male presented with incomplete recovery of vision following pars plana vitrectomy for macular hole in his right eye. The best-corrected visual acuity was 20/60 and 20/20 respectively. Anterior segment was unremarkable. The left eye fundus was normal. The right eye fundus examination (Figure 1a) showed type 1 closure of macular hole. An eccentric full thickness macular hole (EMH) was noted supero-temporal to fovea about two disc diameters away from the center of fovea (blue arrow, Figure 1a). The photograph with blue filter showed prominent inner retinal dimpling (Figure 1b). The en-face SD-OCT showed the presence of concentric macular dark spots and eccentric macular hole (Figure 1c). Conventional SD-OCT B-scan through the eccentric hole showed full thickness macular hole with flat edges (Figure 1d) and confirmed the type 1 closure of primary hole and V-shaped foveal contour (Figure 2). Another depression was seen in temporal retina because of loss of inner retinal layers, suggesting iatrogenic trauma to the retinal surface (Figure 1e). Though the external limiting membrane was intact in foveal area, there was localized disruption of ellipsoid layer, which accounted for the visual status of patient. The patient was diagnosed as having IRD and EMH following pars plana vitrectomy and ILM peeling and was apprised of the situation.
EMHs are a rare complication of ILM or epiretinal membrane peeling. The proposed etiological hypothesis include trauma to the underlying Muller cells causing secondary delayed degeneration of the adjacent retinal neurons,1 iatrogenic trauma to retina2 or contracture at the edge of the peeled epiretinal membrane or ILM.3
The term IRD was coined by Spaide4 and was used to describe the entity, previously known as dissociated optic nerve fiber layer. He suggested that inner retinal dimpling is a result of interplay between trauma and healing processes constrained by nerve fiber layer. The IRD is seen on en-face OCT as concentric macular dark spots.5
This report highlights the concurrence of these two complications of ILM peeling in a single patient. The presence of eccentric macular hole and retinal thinning seen temporal to the fovea (seen in Fig 1e), indicate iatrogenic trauma as the cause of eccentric macular hole in this case. 




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