Fractional anisotropy for assessment of white matter tracts injury in methylmalonic acidemia.

Abstract

Methylmalonic acidemia (MMA) is a multifactorial autosomal recessive inborn error of organic acid metabolism, often presenting with neurological symptoms. As neurological disorders are often related to white matter injury, diffusion tensor imaging (DTI) is an excellent tool for assessment of white matter injury and possibly for diagnosing this disorder. We retrospectively analyzed DTI images of 12 patients with MMA (7 males, 5 females, age range: 7 - 12 months, mean age: 9.25 +/- 1.70 months) with negative MRI findings. And another 12 age-matched and gender-matched infants were enrolled as control subjects. Fractional anisotropy (FA) of different white matter tracts of the brain was measured in both groups. For patients with negative MRI findings, compared with healthy infants, a statistically significant reduction in DTI FA value of the frontal white matter, temporal white matter, and occipital white matter was observed (P < 0.01). In addition to conventional T1W and T2W MR Image, Brain DTI presents a useful, sensitive and complementary tool for the assessment of brain damage in patients with MMA.