Estimation of regional cerebral blood flow in infants by near-infrared topography with ICG

Abstract

This is the report on the use of near-infrared topography (NIRT) with indocyanine green (lCG) to determine regional cerebral blood flow (rCBF) distribution in infants. We measured four infants without neural abnormalities and one infant with bilateral intraventricular and right cerebellar hemorrhage. A probe consisting of 16 optical fibers, 8 for transmission and 8 for detection, was set on the temporal regions of the head of the infant, and 24 measuring points were determined. Changes in regional cerebral ICG concentration were recorded using NIRT. Simultaneously, the arterial blood concentration of ICG was noninvasively measured by pulse dye densitometry using the general principles of pulse oximetry. rCBF was calculated from the modified Fick's equation. The rCBF of fronto-temporal, temporal and occipito-temporal regions ranged from 11.5 to 19.4, 9.8 to 16.9 and 9.7 to 16.6 ml/100 g/min, respectively. It was found that in the area of intracerebral involvement of the infant with hemorrhage, little or no cerebral blood flow was detected. We conclude that our method is useful for measuring rCBF distribution at the bedside in neonates with an illness in the acute phase.