[Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like Episodes(MELAS)]

Area of Science:

• Neurology
• Medical Imaging
• Genetics

Background:

• Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a common mitochondrial disorder.
• Characterized by neurological dysfunction, including seizures and stroke-like episodes, often presenting in youth.
• Diagnosis relies on clinical suspicion and evidence of lactate accumulation in the central nervous system.

Purpose of the Study:

• To highlight the diagnostic significance of neuroimaging findings in MELAS.
• To emphasize the role of MR spectroscopy in detecting lactate accumulation.

Main Methods:

• Review of radiographic features of MELAS.
• Analysis of MRI and MR spectroscopy (MRS) findings in affected individuals.
• Correlation of imaging findings with clinical presentation.

Main Results:

• Stroke-like lesions, typically in the occipito-parietal or posterior temporal lobes, are characteristic radiographic findings.
• MRI reveals high signal intensities on T2-weighted or FLAIR images in affected brain areas.
• A prominent lactate peak on MRS in brain lesions is a crucial indicator of lactate accumulation and supports MELAS diagnosis, especially in pediatric and young adult patients.

Conclusions:

• Neuroimaging, particularly MRI and MRS, plays a vital role in diagnosing MELAS.
• The presence of stroke-like lesions combined with a significant lactate peak on MRS is a key diagnostic marker for MELAS in young individuals.