Cerebrospinal fluid dynamics in infants evaluated with color Doppler US and spectral analysis: respiratory versus arterial synchronization.

Abstract

To investigate rapid cerebrospinal fluid (CSF) dynamics in infants in relation to respiration and cardiac cycle. CSF-flow signals were detected in 35 of 526 consecutive infants (22 male and 13 female infants, aged 1-30 days) who underwent 140 color flow and pulsed Doppler ultrasonographic studies at the cerebral aqueduct. In infants with spontaneous CSF flow, Doppler spectrum and respiratory signal or electrocardiogram were recorded simultaneously. In 64 examinations performed in 20 infants, CSF flow was induced by abdominal pressure change only. Among 76 examinations performed in 15 infants, CSF flow was synchronous to spontaneous respiration in 28 examinations, to mechanical ventilation in nine, to the cardiac cycle in 15, and to both respiratory and heart rates in 24. Respiration-modulated CSF flow predominates in infants without significant intracranial disease. Pulsation or CSF solely or mainly synchronous to the cardiac cycle is associated with conditions causing increased intracranial pressure.