Visual function, ocular motility and ocular characteristics in patients with mitochondrial complex I deficiency
Kristina Teär Fahnehjelm1, Monica Olsson, Karin Naess
1Department of Clinical Neuroscience, Karolinska Institutet and Department of Paediatric Ophthalmology and Strabismus, St. Erik Eye Hospital, Stockholm, Sweden. kristina.fahnehjelm@ki.se
Acta Ophthalmologica
|March 30, 2010
Summary
Children and young adults with complex I deficiency often experience visual impairment and ocular motility issues. Paediatric ophthalmologists should consider mitochondrial disorders in these cases.
Area of Science:
- Ophthalmology
- Genetics
- Biochemistry
Background:
- Complex I deficiency, a condition affecting the mitochondrial respiratory chain, can have significant ocular manifestations.
- Understanding these ocular effects is crucial for early diagnosis and management in pediatric patients.
Purpose of the Study:
- To investigate visual function, ocular motility, and ocular characteristics in pediatric and young adult patients with complex I deficiency.
- To highlight the prevalence of visual impairment and ocular abnormalities in this patient group.
Main Methods:
- A prospective longitudinal study followed 13 patients diagnosed with complex I deficiency between 1995-2007.
- Ocular assessments were conducted between 1997-2009, with a median patient age of 12.8 years.
Main Results:
- Twelve out of 13 patients exhibited visual impairment and/or ocular pathology.
- Eleven patients had ocular motility problems, primarily saccade deficiencies, and five presented with optic atrophy.
- Four siblings with optic atrophy shared similarities with Leber's Hereditary Optic Neuropathy and carried the 11778 G → A mitochondrial DNA mutation.
Conclusions:
- Visual impairment, ocular motility deficits, and optic atrophy are common in complex I deficiency.
- These findings suggest that paediatric ophthalmologists should consider mitochondrial disorders when encountering such ocular issues.
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