Detection of preclinically latent hyperperfusion due to stroke-like episodes by arterial spin-labeling perfusion MRI in MELAS patients

Abstract

In stroke-like episodes (SEs) of patients with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), the detection of preclinically latent lesions is a challenge. We report regional cerebral hyperperfusion observed on arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) in the preclinical phase more than 3 months before the clinical onset of SEs in 3 MELAS patients. These hyperperfused areas were not detected by conventional MRI in the preclinical phase and developed into acute lesions at the clinical onset of SEs, suggesting that ASL imaging has the potential for predicting the emergence of SEs.

Keywords: (123)I-IMP; A-to-G transition at nucleotide position 3243; A3243G; ASL; Arterial spin labeling; CBF; DWIs; FLAIR; MELAS; MRA; MRI; MRS; N-isopropyl-p-[(123)I]iodoamphetamine; PET; Perfusion imaging; SEs; SPECT; Stroke-like episodes; arterial spin labeling; cerebral blood flow; diffusion-weighted images; fluid-attenuated inversion recovery; magnetic resonance angiography; magnetic resonance imaging; magnetic resonance spectroscopy; mitochondrial DNA; mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes; mtDNA; positron emission tomography; rCBF; regional cerebral blood flow; single-photon emission computed tomography; stroke-like episodes.