Persistent Hypotony Post Vitrectomies - A Case Report

Abstract

Hypotony is defined as low intraocular pressure (IOP) which leads to functional and structural changes of the eye, mainly optic nerve, choroid and retina in the posterior pole. There are two types of hypotony which are clinical and statistical hypotony. “Statistical hypotony” refers to IOP which is less than 6.5 mmHg, more than 3 standard deviations below the mean IOP, 1 whereas, “Clinical hypotony” refers to IOP that is low enough to result in loss of vision and it can be caused by structural changes such as astigmatism, corneal oedema, cystoid macular oedema or maculopathy.2 Hypotony maculopathy is characterised by chorioretinal folds, acute optic nerve head oedema and tortuous retinal veins.3 The aetiologies can be due to either increased outflow of aqueous humour, for example in surgical wound leak, over filtrating bleb and cyclodialysis cleft or reduced aqueous humour production, for example in inflammatory conditions.4,5 The risk factors are male gender, young age, myopia, primary glaucoma filtering surgery, especially with the usage of antifibrotic agents, multiple ocular surgeries, vitrectomy and elevated preoperative intraocular pressure.6,7,8 In the present report, we describe a case of a middle-aged gentleman with a background of high myopia who underwent multiple ocular surgeries and presented with postoperative persistent clinical hypotony