Bacterial meningitis in infants: sonographic features.

Twenty-three infants with clinically proven bacterial meningitis were studied with real-time cranial sonography at the time of initial diagnosis and in several cases subsequently. A spectrum of sonographic abnormalities was observed, including bright convolutional markings, focal or diffuse increased and/or decreased parenchymal echoes, ventricular debris, and hydrocephalus. In three infants with virulent Gram-negative meningitis serial sonographic studies showed the development of encephalomalacia. Because clinical neurologic assessment of the infant is limited, a diagnostic imaging method that is sensitive to early structural change and suitable for serial observations is advantageous. Transfontanelle real-time sonographic examination of the brain was found to be a reliable, informative, and relatively inexpensive method of documenting and monitoring complicated bacterial meningitis.