Macular hole developing in a post-vitrectomized eye and its surgical outcome.

Sir,

Macular hole (MH) formation has been attributed to tangential vitreofoveal traction, as described by Gass.[1] However, this mechanism seems to be contradicted in some cases by occurrence of full-thickness MH after spontaneous or surgically induced posterior vitreous detachment (PVD). MH formation has been described after pneumatic retinopexy, scleral buckling, and pars plana vitrectomy.[234] PVD may seem to have a protective effect against future MH formation, but this theory has been proven wrong in many studies.[2]

A 35-year-old man presented with sudden diminution of vision OD since 2 months. On examination, best-corrected visual acuity (BCVA) was 20/50 OD and 20/20 OS. Fundus examination revealed partial rhegmatogenous retinal detachment (RRD) with vitreous hemorrhage and macula was attached. Patient underwent vitrectomy, belt-buckling, membrane-peeling, endolaser photocoagulation, and silicone-oil injection. Six weeks after the surgery, retina was attached and BCVA improved to 20/40, N18. Six months following the primary surgery, the patient underwent phacoemulsification with intraocular lens (IOL) implantation and silicone oil removal. Four weeks later, BCVA improved to 20/40, N6. Eight months later, the patient presented with metamorphopsia OD of 2-months duration. BCVA was 20/40, N12. Fundus examination revealed MH with retina attached [Figure 1a]. Clinical findings were confirmed on optical coherence tomography (OCT) [Figure 1b]. The patient underwent internal limiting membrane (ILM) peeling with 14% C3F8 gas insufflation. Two weeks of prone positioning, 12-14 h/day was advised. Three months later, fundus examination revealed MH to be closed [Figure 2a]. Visual acuity in the right eye improved to 20/32, N6, and OCT confirmed type 1 closure [Figure 2b].

Figure 1

Eight months following retinal detachment surgery. Right eye fundus reveals a full-thickness macular hole (a). Horizontal line scan on OCT confirms the clinical diagnosis (b)

Figure 2

Two months following macular hole surgery. (a) Color fundus photograph of the right eye reveals closed macular hole. (b) OCT confirms “type 1” closure pattern

MHs develop in about 0.5%-1.1% of vitrectomized eyes [Table 1].[45678] The mechanisms of MH development in vitrectomized eyes are not clearly known. MHs that develop in eyes after vitrectomy prove that PVD does not protect against its development. Formation of epiretinal membrane (ERM) causing tangential retinal traction, spontaneous foveal dehiscence following microcystic degeneration, and incomplete separation of posterior hyaloid are some reasons to explain this phenomenon.[8] However, neither ERM formation nor microcystic degeneration were noted on OCT in this reported case pre-operatively. Our patient was aged 35 years at presentation and was much younger than the average reported age at presentation (52.8-63 years).[4678] Our patient developed MH, 13 months following surgery for RRD, which is comparable to that reported in literature [Table 1].[4678] MH closure and visual improvement in this case are also consistent with reports in literature. In the series of Moshfeghi et al.,[4] 50% of patients achieved a visual acuity ≥20/40.

Table 1

Comparison of major studies on macular hole formation in eyes after retinal detachment repair

In summary, MH can develop in vitrectomized eyes and is rare. This phenomenon supports the hypothesis that the traditionally implicated anteroposterior vitreomacular traction is not always essential for the development of a MH. MHs in vitrectomized eyes are amenable to surgery with favorable outcomes. More studies are required to fully understand the etiopathogenesis and the risk factors for development of MHs in eyes undergoing retinal detachment repair.