MELAS syndrome, for Mitochondrial myopathy Encephalopathy Lactic Acidosis Stroke-like, is a rare disease. It can occur as myopathy, encephalopathy, lactic acidosis and acute neurological features like pseudo-cerebrovascular accidents. It is a mitochondrial myopathy, caused by mutations in mitochondrial DNA. It can cause visual disturbances, in particular by cortical damage.
A team of Japanese ophthalmologists conducted a study in five patients with this disease. Their optical coherence tomography (OCT) results were compared with those of five patients with Leber’s hereditary optic neuropathy, another rare disease caused by mutations in mitochondrial DNA, with optic nerve damage, and with those of five healthy control subjects.
Released in November 2020, the results of this study show that all patients with MELAS syndrome had:
- normal visual acuity;
- a ganglion cell complex (GCC) finer on OCT than that of the control participants, even in the absence of a history of transient hemianopsia (common in pseudo-stroke);
- a thicker GCC than that of patients with Leber’s optic neuropathy.
The authors found an inverse correlation between the thickness of the GCC and the duration of MELAS syndrome. They conclude that OCT could become a tool for monitoring this mitochondrial disease and its progression.
