Ultrasound (US) is the first morphological examination of the brain infections in antenatal period as well as in neonates and young infants as long as the fontanels permit.
TORCH Diseases: congenital infections including toxoplasmosis rubella, cytomegalovirus, and herpes simplex are responsible of cortical malformations (CMV) hydrocephalus, brain growth retardation, brain calcification, clastic lesions, microphtalmia and associated visceral anomalies like hepatomegaly, splenomegaly or calcifications (Toxoplasmosis). Diagnosis in most infections is established by serology. Ultrasound demonstrates most of these non specific anomalies with some suggestive pictures: progressive under ependymar cysts, images in candelabrum (CMV), troubles of migration, ventricular dilatations.US contributes to the choice of management and indication of other imaging modalities examination like MRI.
In neonates and young infants acute bacterial meningitis is important cause of mortality and morbidity. It is a clinical diagnosis that is established by the affected patient's history, physical examination findings, and laboratory results. Prognosis depends on the pathogen patient's age and condition and the precocity of diagnosis and appropriate antibiotic treatment. Transfontanellar cerebral explorations shoes at the earlier stage ischemic lesions, cerebral edema: important cause of death, infarction and venous sinus thrombosis. Ventriculitis: is common in neonates, with an incidence as high as 92%, with echoes in the ventricular cavities and echogene ependymar thickness. Complications as the secondary ventricular dilatation, the cerebral abscess. In the pericerebral collections: US permits to situate with precision the localization sub arachnoids' or sub dural effusion, Color Doppler is helpful in these cases. CT and MRI complete the exploration in older children and other meningoencephalites: bacterial, parasitic viral or fungeal infections.