Dellen formation as a complication of subconjunctival silicone oil following microincision vitrectomy

Abstract

PurposeTo study the subconjunctival silicone oil (SCSO) parameters associated with dellen formation following microincision vitrectomy (MIV).Patients and methodsThis was a case–control study of 20 eyes with SCSO following MIV. Ten of them suffered postoperative dellen formation. Dellen occurrence, their sizes, number of loci, and distance between SCSO and the limbus were recorded. The outcome after silicone-oil removal was evaluated.ResultsThe SCSO was at 3.1±1.2 mm from the limbus. All cases with dellen had SCSO within 2 mm of the limbus (P<0.001). No other factors were found to be associated with dellen formation (age, P=0.414; sex, P=0.656; laterality, P=1; indication for pars plana vitrectomy, P=0.655; instrument gauge, P=0.211; circumference involved by SCSO, P=0.252). All the dellen healed after surgical evacuation of SCSO (P<0.001), leaving scars.ConclusionDellen can be associated with MIV secondary to SCSO near the limbus. Resolution with scarring occurred following SCSO evacuation. Therefore, SCSO should be evacuated as early as possible to avoid long-term peripheral corneal morbidity.

A Rare Complication Causing Another Rare Complication: Corneal Dellen with Infiltration Secondary to Subconjunctival Silicon Oil

“…None of the dellen had associated infiltration, which was seen in our case. All the dellen were noted to heal with scar formation after SCSO removal was done during the time of SO removal from the vitreous cavity ( 5 ). Hyung and Min also reported dellen’s disappearance after the removal of SCSO ( 10 ).…”

“…It is important to rapidly reestablish the mucin layer with copious lubricants, and patching of the eye which helps in faster healing and usage of large-diameter BCLs ( 15 ). Since dellen secondary to SCSO may be resistant to topical treatment, early SCSO evacuation will prevent disruption of the ocular surface tear film leading to major complications ( 5 ).…”

“…They occur secondary to paralimbal elevations like filtering blebs, ( 2 ) after strabismus and scleral buckle surgery, ( 1 , 3 ) and have also been reported to occur after silicon oil (SO) leak from the vitreous cavity to the subconjunctival space ( 4 ). Subconjunctival SO (SCSO) following micro incisional vitreoretinal surgery (MIVS) is a known but rare complication ( 5 ). Despite better wound construction, extravasation of SO into the subconjunctival space can still occur through open sclerotomies ( 6 ).…”