MRI features and diagnosis of neonatal deep cerebral arterial infarctions

Objective: To explore the MRI features of neonatal deep cerebral arterial infarctions. Methods: The medical and MRI datas of 23 neonates with deep cerebral arterial infarctions from January 2011 to December 2018 in Beijing Children's Hospital, Capital Medical University were retrospectively analyzed. Both 11 males and 12 females with ages between 1-28 d were recruited and MRI were performed within 2-20 d after symptom onset. The MRI features including location, morphology, signal characteristics, enhancement features and other accompanied signs were reviewed. Results: A total of 15 cases with arterial infarction and 8 cases with complication of purulent meningitis were identified. The median age at presentation were 2 d and 7 d respectively. The unilateral involvement were demonstrated in all neonates with arterial infarctions. Among them, 11 had deep infarcts and the main branch of the middle cerebral artery was involved in 4 neonates. MRI showed slightly hypo-intensity on T₁WI and slightly hyper-intensity on T₂WI with indistinct boundary and focal punctate hyper-intensity on T₁WI and hypo-intensity on T₂WI. In 8 cases secondary to purulent meningitis, unilateral involvement was found in 5 cases and bilateral involvement in 3 cases. All cases showed hypo-intensity on T₁WI and hyper-intensity on T₂WI with indistinct boundary. Among them, 7 cases were heterogeneous, with small cystic changes which appeared as slightly hyper-intensity on T₁WI and slightly hypo-intensity on T₂WI peripherally, as well as nodular or patchy restricted diffusion. Marked swelling of the lesion was found in 6 cases. Multiple patchy or ring enhancement was revealed in 5 cases. Iso-intensity and restricted diffusion in posterior horn of the lateral ventricle were found in 2 cases. Restricted diffusion in frontotemporal subarachnoid space was found in 5 cases. One case showed subdural effusion. Conclusion: Neonatal deep cerebral arterial infarctions have certain characteristic appearance on MRI. Lesions secondary to purulent meningitis can be bilateral involvement with heterogeneous MRI intensities, and different period of infarction signs could be found concurrently. MRI is beneficial to the differential diagnosis. (authors)