Abstract
Abstract: :
Purpose: The mitochondrial DNA point mutation 3243, which is responsible for maternally inherited diabetes and deafness (MIDD) is found in 1-2% of the diabetic population and is associated with a macular dystrophy. The characteristics of fundus autofluorescence in these patients have not been previously described. Methods: A complete history and ophthalmic exam including fundus photos and autofluorescence was performed in ten probands confirmed to have the mitochondrial DNA nucleotide A3243G point mutation. Results: Diabetes was present in 4/10, deafness 5/10, visual symptoms in 6/10, no visual symptoms in 4/10, neurologic 3/10, cardiac 1/10 and renal disease in 1/10 patients each. Positive family history was present in only 5/10 patients. The ophthalmologist made the diagnosis in all ten patients. Fundus findings consisted of two primary phenotypes: irregular patches of paramacular atrophy that coalesced into a ring of atrophy (8/10) or an appearance consistent with pattern macular dystrophy (2/10). In both phenotypes pale subretinal deposits and subretinal pigment clumping were seen. Occasionally changes were seen outside of the arcades and nasal to the optic nerve. Fundus autofluorescence revealed hypofluorescence in the areas of atrophy and hyperfluorescence of the pale subretinal deposits. In areas of the retina that appeared normal clinically, variable sized flecks of hyper- and hypofluorescence were present. This pattern of autofluorescence has not been seen in other macular dystrophies such as Stargardt and geographic atrophy in age-related macular degeneration (AMD). Conclusion: MIDD is a mitochondrial disease with a variable clinical presentation, which can affect multiple organ systems. Fundus autofluorescence reveals a recognizable phenotype allowing MIDD to be distinguished from Stargardt disease and geographic atrophy in AMD. This disorder is not uncommon and the ophthalmologist can make the diagnosis.
Keywords: 432 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 562 retinal degenerations: hereditary