acute comitant esotropia following penetrating keratoplasty

purpose: to report a case of bilateral kertatoconus who presented with acute comitant esotropia after penetrating keratoplasty in the fellow eye. patient and findings: a 17-year-old male with keratoconus underwent penetrating keratoplasty in his right eye. he experienced diplopia after removal of the patch from the operated eye 12 hour postoperatively due to esotropia in his left (unoperated) eye. diplopia was controlled using prism glasses and botulinum toxin a until penetrating keratoplasty was performed in his left eye which resulted in return of fusion which remained stable after 3 years of follow up. conclusion: acute comitant esotropia may occur after loss of fusion due to patching of one eye in a vulnerable patient. in this patient fusion was preserved with non-surgical methods until it was permanently returned surgically.