Efficacy of arterial spin labeling magnetic resonance imaging with multiple post-labeling delays to predict postoperative cerebral hyperperfusion in carotid endarterectomy

ABSTRACT

Introduction: Cerebral hyperperfusion (CHP) syndrome is one of the most deleterious complications after carotid endarterectomy (CEA). Arterial spin labeling (ASL) is a promising non-invasive method to evaluate various hemodynamic parameters in cerebrovascular diseases. The aim of this study was to clarify whether ASL with multiple post-labeling delays (PLDs) can predict postoperative CHP after CEA.

Methods: Sixty-one patients with carotid artery stenosis treated by CEA were retrospectively analyzed. The asymmetry index of the preoperative CBF was obtained from ASL using 3 PLDs (1525 ms, 2025 ms, and 2525 ms) and single-photon emission computed tomography (SPECT). Cerebrovascular reactivity (CVR) was measured from SPECT with acetazolamide challenge. The slope of the regression line obtained from the asymmetry index of three PLDs was defined as the slope index.

Results: The CHP phenomenon was observed in seven patients (11.5%), one of whom developed CHP syndrome (1.6%). Using the CHP phenomenon as a reference standard, the area under the receiver operating characteristics (ROC) was 0.68 for the asymmetry index of the preoperative SPECT, 0.71 for the asymmetry index of the preoperative ASL,0.73 for CVR, and 0.78 for the slope index. Using the cutoff value obtained by ROC analysis, the slope index demonstrated a sensitivity of 85%, specificity of 74%, positive predictive value of 30% and the negative predictive value of 98% for predicting CHP.

Conclusions: The slope index calculated by ASL with multiple PLDs is a useful screening tool to predict postoperative CHP after CEA.

KEYWORDS:

• Arterial spin labeling
• post-labeling delay
• carotid artery stenosis
• carotid endarterectomy
• cerebral hyperperfusion

Acknowledgments

None

Disclosure statement

The authors report no conflicts of interest concerning the materials or methods used in this study, or the findings specified in this paper.

Additional information

Funding

The authors have no funding to report.

Notes on contributors

Hidenori Endo

Hidenori Endo is a faculty staff of Department of Neurosurgery, National Hospital Organization Sendai Medical Center. He is also a lecturer of Department of Neurosurgery, Tohoku University School of Medicine. He specializes in surgical treatment of cerebrovascular diseases including cerebral ischemia, cerebral aneurysm and brain AVMs.

Miki Fujimura

Miki Fujimura is a director and chairman of Department of Neurosurgery, Kohnan Hospital. He specializes in surgical treatment of cerebrovascular diseases, especially moyamoya disease. He has published a lot of papers regarding the relationship between revascularization surgery and cerebral hemodynamics.

Atsushi Saito

Atsushi Saito is a faculty staff of Department of Neurosurgery, Kohnan Hospital. He specializes in surgical treatment of cerebrovascular diseases. He published a lot of papers about basic research of cerebral ischemia.

Toshiki Endo

Toshiki Endo is a lecturer of Department of Neurosurgery, Tohoku University School of Medicine. He specializes in surgical treatment of cerebrovascular diseases and spinal disorders.

Kazumasa Ootomo

Kazumasa Ootomo is a radiology technician of Kohnan Hospital. He contributed to this paper by data collection.

Teiji Tominaga

Teiji Tominaga is a professor and chairman of Department of Neurosurgery, Tohoku University School of Medicine. He specialized in neurosurgical treatment and translational research of cerebrovascular diseases. He also serves as president of Japan Neurosurgical Society.