Abstract
Purpose:
Kearns-Sayre Syndrome (KSS), which is most commonly a sporadic mitochondrial disorder associated with large scale deletions in mtDNA, is a multisystem disease with onset before the age of 20. It’s defined clinically by the triad of chronic progressive external ophthalmoplegia (CPEO), retinal pigmentary degeneration in addition to at least one of the following: heart block, cerebellar dysfunction, and/or cerebrospinal fluid protein concentration of more than 1g/l. The aim of this study was to describe and longitudinally follow-up ophthalmological findings in KSS.
Methods:
15 individuals with KSS (3 males, 12 females) with a mean age of 12.4 years (1.3-35.0 yrs) were diagnosed, eye examined, and followed-up at The Queen Silvia Children’s Hospital, Gothenburg, Sweden, emphasizing on eye motility, ptosis, visual acuity (VA), refraction, corneal thickness (CCT), retinal function, and optic disc status. All were genetically diagnosed with single large scale mtDNA deletions.
Results:
The follow-up mean time was 4 years (0-14 yrs) with a mean of 5 (1-19) examinations performed. Seven patients deceased during the follow-up period at a mean age of 19 years (1.8-43.7 yrs). All but one with KSS developed reduced eye motility over time and in 10/15 it was found at the first examination. In 11 children ptosis was registered initially, and in two other girls during follow-up; four patients had been operated on. In more than half of the cases, VA was relatively stable over time. Myopia (≥-0.5 D SE) was found in five individuals and hyperopia (≥+2.0 D SE) in three and astigmatism (≥1.0 D) was measured in eight children. 6/10 eyes had increased CCT (≥615 microm) and in two girls edematous corneas were developed. Photograph taken by noncontact specular microscope in one of these girls showed abnormal cell morphology. Optic atrophy (OA) was found in 5/13 children and young adults with KSS at first examination and another three individuals developed OA over time. Retinal degeneration was observed in 9/14 at onset and another four developed retinal changes during follow-up. Full-field electroretinogram (ff-ERG) had been performed in 10/13 patients with pigmentary retinopathy of whom eight showed pathological ff-ERG recordings.
Conclusions:
Besides CPEO and retinal degeneration, ptosis, increased CCT, and OA were commonly found among individuals with KSS and these ophthalmological findings seem to progress over time.
Keywords: 600 mitochondria •
461 clinical (human) or epidemiologic studies: natural history •
522 eye movements