Bedside assessment of regional cerebral perfusion using near-infrared spectroscopy and indocyanine green in patients with atherosclerotic occlusive disease

Hiroshi Saito,Shinya Kobayashi,Jun Tanabe,Tatsuya Ishikawa,Junta Moroi

doi:10.1038/s41598-018-19668-5

Abstract

This pilot study aimed to investigate the utility of near-infrared spectroscopy/indocyanine green (NIRS/ICG) for examining patients with occlusive cerebrovascular disease. Twenty-nine patients with chronic-stage atherosclerotic occlusive cerebrovascular disease were included. The patients were monitored using NIRS at the bedside. Using ICG time-intensity curves, the affected-to-unaffected side ratios were calculated for several parameters, including the maximum ICG concentration (ΔICGmax), time to peak (TTP), rise time (RT), and blood flow index (BFI = ΔICGmax/RT), and were compared to the affected-to-unaffected side ratios of the regional cerebral blood flow (rCBF) and regional oxygen extraction fraction (rOEF) obtained using positron emission tomography with 15O-labeled gas. The BFI ratio showed the best correlation with the rCBF ratio among these parameters (r = 0.618; P = 0.0004), and the RT ratio showed the best correlation with the rOEF ratio (r = 0.593; P = 0.0007). The patients were further divided into reduced rCBF or elevated rOEF groups, and the analysis revealed significant related differences. The present results advance the measurement of ICG kinetics using NIRS as a useful tool for the detection of severely impaired perfusion with reduced rCBF or elevated rOEF. This method may be applicable as a monitoring tool for patients with acute ischemic stroke.

Highlights

During acute cerebral stroke, the dynamics of cerebral circulation change continuously, either naturally or intentionally upon therapeutic interventions
Can near-infrared spectroscopy (NIRS)/indocyanine green (ICG) safely be performed at the bedside? In all the thirty-one patients who underwent a bedside NIRS/ICG examination, no side effects appeared to be associated with the examination
Among the NIRS/ICG parameters, the blood flow index (BFI) ratio showed the best correlation with the regional cerebral blood flow (rCBF) ratio (r = 0.618, P = 0.0004; Fig. 1a), while the rise time (RT) ratio showed the best correlation with the regional oxygen extraction fraction (rOEF) ratio (r = 0.593, P = 0.0007; Fig. 1b)

Summary

Introduction

The dynamics of cerebral circulation change continuously, either naturally or intentionally upon therapeutic interventions. It is desirable to establish a convenient bedside examination method that has an acceptable time requirement, and is capable of detecting changes in local cerebral circulation dynamics in the acute phase of stroke in a clinical setting. The evaluation of cerebral circulation with near-infrared spectroscopy (NIRS) and intravenous administration of indocyanine green (ICG) as an intravascular tracer (NIRS/ICG) was first reported by Kuebler et al.[1] They reported that the blood flow index (BFI) significantly correlated with the regional cerebral blood flow (rCBF). The NIRS/ICG approach is considered a useful tool for evaluating the dynamics of cerebral circulation in patients in the acute stage of stroke in a clinical setting. We analyzed how these parameters obtained using NIRS/ICG are correlated with the measured values obtained using PET, which has been considered the gold standard in the evaluation of cerebral circulation and metabolism

Methods

Results

Conclusion