Arterial border zone infarcts in premature neonates lead to periventricular leukomalacia.Periventricular leukomalacia is diagnosed by demonstrating increased echogenicity by brain ultrasound that persists for more than 7 days or is associated with cavitation. The increased echogenicity is best appreciated in the peritrigonal area or in the frontal region. Cavitation occurs 2 to 6 weeks after the hypoperfusion episode (Figure 247.1).
Figure 247.1.— Diagnosis and evolution of periventricular leukomalacia. Increased ecogenicity in the lateral angles of the lateral ventricles and in the peritrigonal region (yellow arrows) at 7 days of age (7 D); cavitation (green arrows) best seen at the frontal region at 20 days (20 D) and 37 days (37 D).
Cavitation may be very extensive. Cavitation is better delineated by MRI of the brain than by ultrasound (Figure 247.2). Periventricular leukomalacia may also occur in neonates with ventriculitis, metabolic disorders, and hydrocephalus. Periventricular leukomalacia is usually asymptomatic during the neonatal period.
zone infarct in fullterm neonates
Single artery brain infarct
artery cerebral infarct occurs more frequently in the distribution of
the middle cerebral artery (Figure 247.3). The left hemisphere is more
frequently involved than the right hemisphere. Patients who have undergone
extracorporeal circulatory support are at risk for single artery brain
Figure 247.3.— [A] CT of the brain demonstrating a large infarct in the distribution of the middle cerebral artery. [B] MRI of the brain (T2-weighted image) demonstrating a small posterior limb infarct in the internal capsule.
Multiple artery brain infarcts
Multiple artery brain infarcts occur less frequently than single artery brain infarcts. Meningitis should be considered as a possible cause.