Purpose: Mutations of mitochondrial DNA can lead to a variety of pheno- and genotypically heterogeneous diseases. Kearns-Sayre syndrome is caused by the deletion of several mitochondrial genes. The syndrome is characterized by chronic progressive external ophthalmoplegia, tapetoretinal degeneration, and severe generalized myopathy.
Case report: We report on a 36-year-old female patient with Kearns-Sayre syndrome, confirmed by biochemistry, histology, and genetics. Over a period of 10 years, progressive ophthalmoplegia led to recurrent conjunctivitis, keratitis, and corneal ulceration. Almost total external ophthalmoplegia including involvement of the orbicularis oculi muscles was observed. Despite advanced ptosis, there was lagophthalmos of 2 mm with near complete extinction of globe motility in both eyes. The left eye showed a peripheral corneal perforation parallel to the lower limbus. After successful penetrating keratoplasty in the left eye, despite preventive measures, a peripheral corneal perforation also occurred in the right eye. Penetrating keratoplasty was therefore also performed on the right eye. To achieve a satisfactory functional result, large-diameter transplants were necessary in both eyes. To prevent immune reactions, cyclosporine therapy was initiated prophylactically. Sixteen and 9 months after penetrating keratoplasty, the corrected visual acuity was 20/60 in the right eye and 20/100 in the left eye, with clear transplants on both sides.
Discussion: Patients with progressive ophthalmoplegia require thorough neurologic investigation and evaluation. Lagophthalmos in the presence of almost absent globe motility requires extensive preventive measures to avoid exposure keratitis. In spite of this, in the presented case, corneal perforation of the second eye could not be prevented.