title: NEW OBSERVATIONS REGARDING THE RETINOPATHY OF GENETICALLY CONFIRMED KEARNS-SAYRE SYNDROME.
abstract: OBJECTIVE
  To report novel retinal findings in Kearns-Sayre syndrome and correlate degree of retinopathy with other clinical findings.
  
  
  METHODS
  Observational case series of patients from Saudi Arabia with retinal and neuroophthalmologic examinations, medical chart review, and mitochondrial genetic evaluation.
  
  
  RESULTS
  The three unrelated patients had progressive external ophthalmoplegia and pigmentary retinopathy bilaterally. Muscle biopsy in two of the cases revealed mitochondrial myopathy. All three had abnormal findings on neuroimaging and modestly reduced visual acuity in both eyes with a variable pigmentary retinopathy. One of the patients had bilateral subretinal fibrosis with a full-thickness macular hole in the right eye. All three patients had single, large-scale mitochondrial DNA (mtDNA) deletions (5.0-7.6 kb in size) with blood mtDNA heteroplasmy levels ranging from below 20% to 57%. Severity of pigmentary retinopathy did not correlate with severity of progressive external ophthalmoplegia, but did correspond grossly with electroretinographic abnormalities, just as the degree of ocular motility restriction and ptosis in each patient correlated with the size of their extraocular muscles on neuroimaging. In addition, the size of the single, large-scale mtDNA deletion and level of mtDNA heteroplasmy corresponded with degree of ocular motility restriction but not with severity of retinopathy.
  
  
  CONCLUSIONS
  Subretinal fibrosis and macular hole are novel retinal observations which expand clinical profile in Kearns-Sayre syndrome. Genetic testing for mtDNA deletions and heteroplasmy in blood, muscle biopsy, careful ocular and retinal examination including electroretinography, and imaging are indispensable tests for this condition.
authors.affiliation: King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia.
authors.forename: Igor
authors.initials: I
authors.lastname: Kozak
authors.affiliation: Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.|The Division of Ophthalmology, Faculty of Health Sciences, University of Stellenbosch, Tygerberg, South Africa.
authors.forename: Darren T
authors.initials: DT
authors.lastname: Oystreck
authors.affiliation: Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.|Department of Ophthalmology, College of Medicine, University of Florida, Jacksonville, Florida.
authors.forename: Khaled K
authors.initials: KK
authors.lastname: Abu-Amero
authors.affiliation: King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia.
authors.forename: Sawsan R
authors.initials: SR
authors.lastname: Nowilaty
authors.affiliation: Departments of Pathology, and.
authors.forename: Hisham
authors.initials: H
authors.lastname: Alkhalidi
authors.affiliation: King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia.
authors.forename: Sahar M
authors.initials: SM
authors.lastname: Elkhamary
authors.affiliation: Pediatrics, College of Medicine, King Saud University Riyadh, Saudi Arabia.
authors.forename: Sarar
authors.initials: S
authors.lastname: Mohamed
authors.affiliation: Pediatrics, College of Medicine, King Saud University Riyadh, Saudi Arabia.
authors.forename: Muddathir H A
authors.initials: MHA
authors.lastname: Hamad
authors.affiliation: Pediatrics, College of Medicine, King Saud University Riyadh, Saudi Arabia.
authors.forename: Mustafa A
authors.initials: MA
authors.lastname: Salih
authors.affiliation: The Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Emma L
authors.initials: EL
authors.lastname: Blakely
authors.affiliation: The Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Taylor
authors.affiliation: Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.|The Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Bosley
mesh_terms: D000293:Adolescent; D002648:Child; D004596:Electroretinography; D005260:Female; D006801:Humans; D007625:Kearns-Sayre Syndrome / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D012164:Retinal Diseases / Q000473:pathology* / Q000503:physiopathology; D012167:Retinal Perforations / Q000473:pathology; D012174:Retinitis Pigmentosa / Q000473:pathology