The use of silicone oil-RMN3 (Oxane HD) as heavier-than-water internal tamponade in complicated inferior retinal detachment surgery.

BACKGROUND

Conventional silicone oil provides suboptimal support of the inferior retina. In this study we evaluated the efficacy of Oxane HD in the management of complex retinal detachments involving lower quadrants of the retina.

METHODS

A prospective, interventional, comparative study. Eighteen patients were recruited. Treatment outcomes were compared with a historical control group of 14 patients. Patients with grade C3 PVR or greater and inferior retinal breaks, recurrent inferior retinal detachments (with or without PVR) and giant retinal tears were included. In those patients who re-detached under heavy silicone oil (n = 4), retro-oil epiretinal membranes (ERMs) were obtained at the time of subsequent surgery to analyse the immunopathological response to oxane HD. Immunohistochemistry was used to detect glia, retinal pigment epithelium cells (RPE), macrophages, T lymphocytes, or neural elements in the tissue using well-characterised monoclonal antibodies.

RESULTS

Retinal attachment of the posterior pole following removal of silicone oil was achieved in 66.6% of the treatment group (n = 12) and 64.3% of controls (n = 9) (p = 1.0). Post-operative PVR developed in five patients in the treatment group (27.8%) and five control patients (35.8%). Following removal of silicone oil, residual oil was observed in 27.8% of the treatment group and 7.1% of controls. Median visual acuity, 3 months following removal of silicone oil, was 2.0 (IQR 0.9-2.0) in the treatment group and 1.0 (IQR 0.6-1.8) in the control group. Complications in the treatment group included, hypotony (n = 3), uveitis (n = 2), glaucoma (n = 1). All ERMs analysed demonstrated microscopic appearances typical of PVR. The membranes were fibrocellular in nature, contained RPE and glial cells, and variable amounts of intracellular and extracellular pigment. In addition, all had a dense infiltrate of vacuolated (presumed oil-filled) macrophages.

CONCLUSION

We failed to observe an advantage following the use of Oxane HD in the treatment of inferior retinal detachments. Moreover, Oxane HD was difficult to remove and was associated with a higher incidence of complications.