History and Physical
A 2-year-old boy was referred for use of only his left hand and clumsiness when walking. Pregnancy was complicated by gestational diabetes with good metabolic control. He was born by vaginal delivery without complications at 40 weeks of gestational age. He had motor delays and walked independently at 18 months of age, as well as expressive and receptive language delays. Social milestones were normal for age. Physical examination revealed spasticity of the right arm and leg with associated hyperreflexia and Babinski sign. The left side was neurologically normal. He walked with internal rotation of the right foot and circumduction with associated elbow flexion and forearm pronation.
Diagnostic Workup
MRI showed left periventricular white matter signal abnormalities corresponding to gliosis, associated with ex vacuo ventricular dilation. Traversing linear susceptibility was compatible with medullary venous injury ( Fig. 12.1 ).
Left medullary venous thrombosis. Brain MRI, (A and B) axial FLAIR, (C) coronal T2, and (D) SWI show hyperintense signal and volume loss in the left periventricular white matter, associated with ex vacuo ventricular dilatation and medullary venous thrombosis ( arrows ). FLAIR , Fluid-attenuated inversion recovery; SWI , susceptibility-weighted imaging.
Clinical Differential Diagnoses
Causes of congenital hemiparesis include large artery infarcts, small artery infarcts, and malformations of cortical development.
Mutations in type IV collagen ( COL4A1 or COL4A2 genes) are associated with familial hemorrhagic strokes, congenital porencephalic cysts, and multisystem cardiac, ocular, muscular, and/or renal findings.
Imaging Differential Diagnoses
Perinatal large artery infarcts classically show cystic encephalomalacia affecting the cortex and subcortical white matter in the territory of the affected artery ( Fig. 12.2 ). Perinatal hemorrhagic stroke can be easily diagnosed with susceptibility-weighted MRI for detection of remote parenchymal hemorrhage.
Right MCA infarct. Brain MRI, (A) axial T2 and (B) T1 show right MCA territory cystic encephalomalacia ( arrows ) with ex vacuo dilation of the right lateral ventricle. MCA , Middle cerebral artery.
Small artery lacunar infarcts are more localized, with a rounded or triangular morphology. Basal ganglia involvement is common with lenticulostriate artery infarcts.
Periventricular leukomalacia is associated with preterm birth and can demonstrate diffuse or asymmetric white matter injury, intraventricular hemorrhage, and ex vacuo ventricular dilation ( Fig. 12.3 ).
