Assessment of Cortical Hemodynamics by Multichannel Near-Infrared Spectroscopy in Steno-Occlusive Disease of the Middle Cerebral Artery

Abstract

Background and Purpose-In a pilot study we evaluated near-infrared spectroscopy as to its potential benefit in monitoring patients with steno-occlusive disease of a major cerebral artery for alterations in cortical hemodynamics. Methods-Cortical maps of time-to-peak (TTP) in 10 patients unilaterally affected by severe stenosis or occlusion of the middle cerebral artery were acquired by multichannel near-infrared spectroscopy after bolus application of indocyanine green. Hemodynamic manifestations were assessed by comparison between affected and unaffected hemisphere and evaluated for common constituents by principal component analysis. In one patient, TTP values were compared with those obtained by dynamic susceptibility contrast imaging. Results-TTP was increased on the affected hemisphere in 9 patients. Mean difference in TTP between hemispheres was 0.44 second (P<0.05) as compared with a mean lateral difference of 0.12 second found in a control group of 10 individuals. In group analysis a significant rise in TTP was found in the distribution of the affected middle cerebral artery, whereas principal component analysis suggests augmentation of hemodynamic effects toward the border zones as a dominant pattern. A linear correlation of 0.61 between TTP values determined by dynamic susceptibility contrast MRI and nearinfrared spectroscopy was found to be statistically significant (P<0.001). Conclusion-Multichannel

Time-resolved multi-channel optical system for assessment of brain oxygenation and perfusion by monitoring of diffuse reflectance and fluorescence

“…ICG [82]. Quality of the signals measured suggest that the instru− ment can be used in estimation of brain perfusion using techniques proposed in several previous studies [37,39,40,44,83,84].…”

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

“…Similarly, in the present study, BFI was the parameter that showed the best correlation with rCBF. Its usefulness has been reported in patients with acute ischemic stroke and congenital heart disease, as well as in cerebral blood flow monitoring during carotid endarterectomy 2 , 5 – 8 . It has been previously reported that TTP, RT, and BFI significantly change in patients with cerebral infarction, and that the TTP measures obtained from NIRS/ICG test strongly correlated with those obtained by MR perfusion imaging 6 , 7 .…”

Spatial mapping of dynamic cerebral autoregulation by multichannel near-infrared spectroscopy in high-grade carotid artery disease

“…19 Multichannel NIRS has also been applied for perfusion measurement in adults with MCA stenosis and a delayed perfusion predominantly in the vascular border zone has been found in Ref. 20. Although the anterior cortical border zone is a well described area for (hemodynamic) infarction in carotid artery disease, 21 no experimental studies examining cerebral autoregulation in this area exist in humans so far because of possible harm during pharmacological blood pressure reduction.…”