Macular hole has been reported as a rare complication of adult vitelliform macular dystrophy (AVMD),1 and to date no cases have been reported where surgery has lead to successful hole closure. In this report, we found it necessary to use a heavy silicone oil tamponade to ensure permanent hole closure in a patient with AVMD.
A 73-year-old man was referred with a history of AVMD and recent visual loss. He was found to have a macular hole in his right eye (Fig. 1a). We confirmed the associated diagnosis of AVMD by the presence of the typical submacular yellow vitelliform deposits in the left eye (Fig. 1b), and by colour fundus photo-documentation of symmetric and bilateral vitelliform maculopathy from 1 year before. Best corrected visual acuities were 6/18-2 in the right eye and 6/12 in the left eye. There was a full thickness macular defect in the right eye as documented by optical coherence tomography, together with an associated posterior hyaloidal tractional band (Fig. 1c). The left macula had vitreo-macular traction and typical deposits beneath the retina were seen (Fig. 1d). Both eyes were otherwise normal apart from mild nuclear cataracts.
The patient consented to surgery on the right eye and a 25-gauge transconjunctival sutureless vitrectomy was performed together with phacoemulsification and intraocular lens implantation. The surgery included a standard pars plana vitrectomy, inner limiting membrane peeling (area of approximately 2 disc diameters) over central macula assisted by Brilliant Blue dye (brilliant peel, Fluoron, Geuder, Germany) and 20% sulphur hexafluoride as gas tamponade. The patient adopted postoperative prone positioning for 5 days.
Initial anatomical success was achieved with this procedure and confirmed with optical coherence tomography. (Fig. 2a) However, 7 weeks following surgery, spontaneous reopening of the hole occurred (Fig. 2b). Based on favourable outcomes2 with the use of ‘heavy’ silicone oil in failed idiopathic macular hole surgeries, and the need of an adjuvant in redo surgeries,3 we offered this new alternative to the patient.
The surgery included confirmation of complete macular inner limiting membrane peeling (performed in the previous surgery) assisted by Brilliant Blue and following the fluid/air exchange, Oxane HD (Bausch & Lomb, St Louis, MO, USA) was injected into the vitreous cavity. The hole was successfully closed (Fig. 2c) on the first postoperative day and has remained so for 25 months (Fig. 2d; optical coherence tomography image taken 9 months after oil removal). The heavy silicone oil was removed 15 weeks after it was injected. The most recent visual acuity was 6/12 unaided (pinholing to 6/9) measured 21 months after removal of heavy silicone oil.
Macular hole is a rare complication of AVMD. To the best of our knowledge, only two cases have been documented in the literature without associated retinal detachment1,4 and no surgical repair has been attempted.
It is likely that the subretinal location of this material contributes to progressive foveal thinning5 and retinal pigment epithelium (RPE) atrophy which along with tractional forces directed to the inner retina contribute to macular hole formation. Additionally, the thinning at the fovea may make these cases resistant to standard surgical treatment of macular holes, thus requiring a longer lasting endotamponade than the long-standing gases. Such endotamponade should provide a better scaffold effect for proliferating glial cells to seal the macular hole after the re-absorption of the inner retinal oedema. Standard and ‘heavier-than-water’ silicone oils are alternatives to long-acting gases. However, heavy silicone oil has a higher specific gravity that, along with its amphiphilic nature, provides a greater weight and adhesion force to the retina than the hydrophobic standard silicone oil alone. These features provide an excellent interfacial contact at the macula regardless of patient posture.2 Furthermore, the smaller aqueous phase facing the fovea promotes a higher concentration of growth factors. These factors seem necessary to create the mild inflammatory reaction on the retinal surface to ‘plug’ the macula, limiting inner retinal hydration and theoretically reducing the risk of reopening. These were our rationale premises for using heavy silicone oil in approaching the rare and recurrent macular hole case associated with AVMD. Reported complications using heavy silicone oil include increased intraocular pressure, emulsification and cataract formation.2
The excellent anatomical and functional outcome of this patient reinforces the utility of heavy silicone oils in those cases of primary failures following macular hole surgery even if associated with other coexistent maculopathies such as AVMD.