Differentiation between peritrigonal terminal zones and hypoxic-ischemic white matter injury on MRI.

The differentiation between terminal zones and pathological signal intensity changes on MRI of children and young adults is of diagnostic importance. We assessed the diagnostic value of several morphological features on MRI to differentiate between terminal zones and hypoxic-ischemic white matter injury. We selected all brain MRI examinations performed in subjects up to 20 years of age showing increased signal intensity on T2-weighted images in the peritrigonal areas. 75 individuals were assigned to a patient group (n=28) if there was evidence of hypoxia-ischemia during the perinatal period or a control group (n=47). Aspect, location, extent, shape, and borders of signal intensity changes in the peritrigonal areas were studied. Signal intensity of the peritrigonal areas was related to signal intensity of surrounding white matter. Presence of Virchow Robin spaces, hypoxic-ischemic abnormalities, and local atrophy were also recorded. Chi-squared tests assessed whether presence or absence of morphological characteristics differed between patients and controls. Logistic regression analysis studied which characteristics were best to discriminate between the two groups. Very high signal intensity of the peritrigonal areas on FLAIR (Odds Ratio 25) and presence of local atrophy (Odds Ratio 14.3) were best predictors to discriminate between the two groups.