Diffusion-Weighted Imaging of Periventricular Leukomalacia in Very Young Children: Assessment of Peritrigonal Stripe of Restricted Diffusion.

 In periventricular leukomalacia (PVL), apparent diffusion coefficient (ADC) reduction, normally shown as dark stripe in the peritrigonal (PT) white matter, may be incomplete. We assessed the PT dark stripe to differentiate between PVL patients and control subjects.  We reviewed the magnetic resonance studies of 27 neonates and young children with PVL and 67 control subjects to assess the PT dark stripe on ADC maps. In PVL patients, the assessment was referred to the location of PVL lesion on fluid-attenuated inversion recovery (FLAIR) imaging. In the controls, the PT region or the location corresponding to FLAIR hyperintensity was evaluated for the dark stripe. We compared the prevalence of the dark stripe on ADC map and the PT FLAIR hyperintensity between the PVL and the control subjects.  On ADC map, complete PT dark stripe was present in 67 (100%) of 67 controls but only in 4 (14.8%) of 27 PVL patients (-value < 0.01), with sensitivity of 0.85, specificity of 1.0, and accuracy of 0.96. PT FLAIR hyperintensity was present in 44 (65.7%) of 67 controls and in 18 (66.7%) of 27 PVL patients ( = 0.920).  PVL patients can be differentiated from the control subjects with PT dark stripe on ADC map.