Strabismus Surgery for a Patient with Toxocara Retinochoroidal Granuloma Causing Macula Heterotropia and Abnormal Vertical Angle Kappa: A Case Report

Abstract

Introduction: Angle kappa is important in our clinical practice as it can give the appearance of strabismus. A vertical angle kappa is secondary to macula heterotropia as a result of retinal traction from scar tissue in the posterior pole. Case report: We present an interesting case of a 25 year-old Chinese female who presented with an abnormal vertical angle kappa due to macula ectopia from a toxocara retinochoroidal granuloma. She had an apparent right exotropia and hypotropia on Hirschberg and Krimsky but a hypertropia on alternate prism cover test. Our patient was keen for surgical correction as she was bothered by the appearance of her large angle squint. The main concern about strabismus surgery in patients with angle kappa was that it could break down the patient’s fusion and cause diplopia. Conclusion: The management of vertical angle kappa is difficult and odifficult to treat surgically. We describe this rare case of a patient who underwent surgical correction of only the horizontal recti and she achieved apparent orthophoria with a good cosmetic outcome. Patient also had no diplopia post-operatively.