Orthoptic Treatment of Convergence Insufficiency in Parkinson's Disease: A Case Series.

Introduction: This study reports a case series of orthoptic treatment (OT) for convergence insufficiency (CI) in individuals with Parkinson's disease (PD). Method: We are reporting two cases of individuals with PD who completed OT for CI. Both had a confirmed diagnosis of CI, accompanied by CI-type symptomatology. They each underwent an OT program consisting of three office-based visits and 8 weeks of home-based exercises. Treatment outcome was based on the changes measured pre- versus post-OT on the near point of convergence, positive fusional vergences, and symptomatology score. Results: The two participants successfully completed therapy, gained ability to converge, had fewer symptoms, and were satisfied with the OT-induced changes they felt in their day-to-day lives. Conclusion: This case series show that OT for CI in PD is possible. Further research is required as these results demonstrate that OT has the potential to improve symptomatic CI in these patients. In the meantime, the positive results obtained in these two cases should encourage clinicians to consider OT (a therapy with no/minimal risk) for CI in patients with PD whose quality of life is affected by this binocular dysfunction.