INTRACRANIAL COMPLIANCE IN INFANTS - EVALUATION WITH DOPPLER US

PURPOSE: To test graded fontanelle compression during Doppler ultrasound (US) scanning to identify and monitor infants with altered cranial compliance. MATERIALS AND METHODS: An ophthalmodynamometer exerted pressure on the anterior fontanelle during Doppler US scanning of the middle cerebral artery. Sixty examinations were performed in 43 infants-13 full-term and 11 premature healthy control subjects, 10 with increased intracranial volume, and nine with suspected abnormal cranial compliance but without increased intracranial volume. Resistive index (RI) and angle-corrected time-averaged mean velocities (TAV) of blood flow were compared at three different pressures. RESULTS: Baseline RI values in healthy full-term infants were significantly lower than in healthy premature infants and infants with abnormal compliance (P < .05). Values for healthy premature infants and infants with abnormal compliance were indistinguishable (P > .5). Neither RI nor TAV changed significantly in healthy infants, but both changed significantly with compression in infants with abnormal cranial compliance. CONCLUSION: This procedure may be more useful than measurement of RI of the anterior cerebral artery alone to evaluate infants with altered cranial compliance.