A cluster of patients with inferior rectus restriction following local anesthesia for cataract surgery.

During a 5-month period, four patients developed contracture of the inferior rectus muscle following local anesthesia for cataract surgery in the practice of one ophthalmologist. Two anesthesiologists administered retrobulbar anesthesia. All patients had persistent vertical diplopia caused by a large hypotropia of the operated eye. Forced duction testing revealed marked restriction to elevation of the eye. In two patients, MRI demonstrated segmental thickening of the inferior rectus muscle, just posterior to the globe. All patients had normal thyroid function tests. No patient had a previous history of strabismus. Three of the four have had strabismus surgery consisting of recession of the markedly restricted inferior rectus muscle on an adjustable suture. These three patients have regained fusion and are now asymptomatic.