Figure 12.

Other forms of acute injury. (A,B) Preterm infant (GA 27 weeks) with bilateral middle cerebral artery (MCA) territory infarction. (A) Coronal ultrasound scan 3 weeks after birth shows extensive cystic injury in the right frontoparietal region (arrows), but located more lateral than expected for common periventricular WMI. Focal echodensity was first identified at this location on cUS 7 days after birth (not shown). (B) Axial T2-weighted MR image shows the large right MCA cortical infarct and an additional smaller left MCA cortical infarct (arrowheads) that was not readily appreciated on cUS because of its far lateral location. The bilateral MCA strokes suggest a proximal embolic source, and placenta was suspected. (C,D) Perforator stroke in a preterm infant (GA 34 weeks). (C) Coronal ultrasound scan, at the level of the third ventricle and foramen of Monro, performed after surgery for ventriculoseptal defect closure shows a focal echodensity in the medial right capsuloganglionic region (arrow). cUS performed prior to surgery did not show any abnormality. Findings are most consistent with lenticulostriate territory infarction (middle cerebral artery perforating branches). (D) Axial T2-weighted MR image after 2 weeks shows cystic evolution of the infarct without evidence of previous hemorrhage (arrowhead).