In their paper, the authors described a novel method to assess perfusion in perinatal strokes in the ischemic as well as penumbra tissue.
They included subjects less than 28 days old at time of diagnosis, and included both arterial and venous infarcts. MRI was carried out on 3T scanners with arterial spin labeling (ASL) techniques used for non-contrast perfusion imaging. Out of 25 neonates that participated, 16 were males (64%). Median gestational age at birth was 38.7 weeks (range: 35.7-41.9), median (estimated) age at stroke was 1 day (i.e., second day of life) (range: 0-8), and median age at MRI was 3 days (range: 0-16). The median time from symptom onset to MRI acquisition was 2 days (range: 0-8).
Arterial ischemic stroke was present in 11 (44%), while venous infarction was found in 9 (36%). Five patients (20%) had both arterial and venous stroke. Hyperperfusion was seen in 73% of arterial ischemic strokes, 11% with venous stroke, and 80% with both. Hypoperfusion was observed in 33% with venous and none with arterial stroke. Perfusion was normal in 45% with venous and 20% with both. In nearly all patients presenting with clinical or electrographic seizures, EEG abnormalities were present in the same hemisphere as the stroke; this clinical feature did not differ by stroke type.
This study demonstrates that perfusion imaging can be obtained in neonates with acute stroke, and often reveals hyperperfusion in the infarct core. Penumbra in arterial infarcts is seldom found. Hyperperfusion may be due to post-stroke reperfusion or to neuronal hyperexcitability of stroke-associated seizure.