Prostaglandin analogues: A double-edged sword in orbital glaucoma disease management

Introduction: The authors describe benefits of the recognised adverse effects of prostaglandin analogues on periocular structures in patients with unilateral proptosis and intraocular pressure rise. This case points to intentional consideration of prostaglandin analogue therapy in this selected cohort of patients with secondary ocular hypertension and proptosis. Case description: A 70-year-old gentleman who presented with a 1-week history of a red and painful right eye associated with tortuous and dilated episcleral blood vessels. Visual acuity was unaffected. A diagnosis of idiopathic orbital inflammatory disease was made by extraocular muscle biopsy. Two weeks later, the patient presented with worsening pain, reduced vision and raised intraocular pressure. The secondary ocular hypertension was successfully treated with topical preserved eye drops, including latanoprost, a prostaglandin analogue. Over 6 months, the patient developed drop intolerance and punctate keratopathy leading to therapy non-adherence. Interestingly, the patient reported improvement in periocular appearance related to prostaglandin-associated periorbitopathy. Ocular surface disease and intraocular pressures were subsequently managed with preservative-free eye drops. Conclusion: Secondary ocular hypertension is not an uncommon consequence of orbital disease. Prostaglandin analogue can act as a double-edged sword in the management of raised intraocular pressure by reducing eye pressure at the cost of developing adverse effects of prostaglandin-associated periorbitopathy. These adverse effects however can be beneficial in the aesthetic rehabilitation of proptosis and associated exposure keratopathy in patients with unilateral orbital disease and probably should be sought as first line treatment in those with proptosis and raised intraocular pressure.