Fiber-tracking techniques can predict the degree of neurologic impairment for periventricular leukomalacia

OBJECTIVE. Preterm or low birth weight infants display a greater propensity for white matter injury caused by hypoxic-ischemic encephalopathy in the perinatal period. Such episodes can result in periventricular leukomalacia, which may substantially influence later brain development. Noninvasive methods of assessing the severity of injury at the earliest stage of life have not yet been established. METHODS. We used diffusion tensor imaging to evaluate sensorimotor fibers in periventricular leukomalacia. Region-of-interest measurements and tractography-based measurements were performed for 10 patients with periventricular leukomalacia. The mean age of the patients was 19 +/- 9.5 months (range: 9-41 months). Motor functions were assessed at a mean age of 28 +/- 14.5 months. RESULTS. Measured fractional anisotropy values of the motor tract were significantly higher in all mild periventricular leukomalacia cases than in severe cases. A fractional anisotropy cutoff value of <0.5 was useful for predicting severe periventricular leukomalacia. Region-of-interest measurements were less sensitive, compared with tractography-based measurements. CONCLUSIONS. Fiber-tracking techniques can provide information on the pathophysiologic features of motor disability in patients with periventricular leukomalacia. Early screening of patients with a history of asphyxia may facilitate early intervention (eg, rehabilitation), to achieve better motor function.