Real-Time Monitoring of Cerebrovascular Insufficiency due to Emergent Large Vessel Occlusion Using Near-Infrared Spectroscopy Based on the Modified Beer-Lambert Law: A Retrospective Study

Sho Okune; Aiki Marushima; Yasuaki Koyama; Shun Tanaka; Kota Araki; Takeshi Yoshimoto; Tenyu Hino; Taisuke Akimoto; Koji Hirata; Hisayuki Hosoo; Masayuki Sato; Yoshiro Ito; Mikito Hayakawa; Eiichi Ishikawa; Hiroshi Yamagami; Yuji Matsumaru

doi:10.1016/j.wneu.2025.124277

Real-Time Monitoring of Cerebrovascular Insufficiency due to Emergent Large Vessel Occlusion Using Near-Infrared Spectroscopy Based on the Modified Beer-Lambert Law: A Retrospective Study

World Neurosurg. 2025 Sep:201:124277. doi: 10.1016/j.wneu.2025.124277. Epub 2025 Jul 11.

Authors

Sho Okune¹, Aiki Marushima², Yasuaki Koyama³, Shun Tanaka⁴, Kota Araki⁵, Takeshi Yoshimoto⁴, Tenyu Hino⁴, Taisuke Akimoto⁵, Koji Hirata⁵, Hisayuki Hosoo⁶, Masayuki Sato⁵, Yoshiro Ito⁵, Mikito Hayakawa⁴, Eiichi Ishikawa⁷, Hiroshi Yamagami⁸, Yuji Matsumaru⁹

Affiliations

¹ Department of Stroke and Cerebrovascular Diseases, University of Tsukuba Hospital, Tsukuba, Ibaraki, Japan; Doctoral Program in Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
² Department of Stroke and Cerebrovascular Diseases, University of Tsukuba Hospital, Tsukuba, Ibaraki, Japan; Department of Emergency and Critical Care Medicine, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan; Center for Cybernics Research, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan. Electronic address: aiki.marushima@md.tsukuba.ac.jp.
³ Department of Emergency and Critical Care Medicine, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
⁴ Department of Stroke and Cerebrovascular Diseases, University of Tsukuba Hospital, Tsukuba, Ibaraki, Japan.
⁵ Department of Stroke and Cerebrovascular Diseases, University of Tsukuba Hospital, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
⁶ Department of Stroke and Cerebrovascular Diseases, University of Tsukuba Hospital, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan; Division of Stroke Prevention and Treatment, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
⁷ Department of Neurosurgery, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
⁸ Department of Stroke and Cerebrovascular Diseases, University of Tsukuba Hospital, Tsukuba, Ibaraki, Japan; Division of Stroke Prevention and Treatment, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
⁹ Department of Stroke and Cerebrovascular Diseases, University of Tsukuba Hospital, Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan; Center for Cybernics Research, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.

PMID: 40653012
DOI: 10.1016/j.wneu.2025.124277

Abstract

Background: Near-infrared spectroscopy (NIRS) is commonly used to assess brain tissue oxygen levels during surgery, but its applicability in the acute phase of stroke remains uncertain. We examined the usefulness of NIRS for rapid identification of acute large vessel occlusion (LVO) on hospital arrival.

Methods: This pilot, single-center, retrospective study used a prospective database including all patients with suspected stroke. We performed NIRS upon hospital arrival. Based on the modified Beer-Lambert law, which enables high-frequency signal analysis, we used a newly defined index, pulse-oxygenation (PlsO₂), representing hemoglobin oxygen saturation derived from the pulsatile component of the NIRS signal. The primary outcome was the diagnostic accuracy of NIRS in distinguishing LVO from other conditions, assessed using the PlsO₂ ratios between the affected and unaffected sides.

Results: Data from 114 (40.4%) patients were analyzed. Relative PlsO₂ was lower in the LVO (n = 35) than in the non-LVO group (n = 79; 0.975 [0.874-0.991] vs. 1.022 [0.986-1.055], P < 0.001). The area under the receiver operating characteristic curve for relative PlsO₂ in LVO was 0.778 with sensitivity, specificity, positive predictive value, and negative predictive value of 74.3%, 69.6%, and 52.0%, and 85.9%, respectively, using an optimal cutoff.

Conclusions: NIRS shows potential utility in detecting LVO in patients with suspected stroke. The results of this study provide a critical foundation for the future application of NIRS in the early identification and prehospital triage of LVO. Further large-scale studies are indispensable to establish its utility for early triage of emergency prehospital LVO.

Keywords: Cerebrovascular circulation; Cerebrovascular disorders; Large vessel occlusion; Near-infrared spectroscopy; Thrombectomy.

MeSH terms

Aged
Aged, 80 and over
Cerebrovascular Disorders* / diagnostic imaging
Female
Humans
Male
Middle Aged
Monitoring, Physiologic / methods
Pilot Projects
Retrospective Studies
Spectroscopy, Near-Infrared / methods
Stroke* / diagnostic imaging