Évaluation de la fidélité intra- et interobservateur pour l’évaluation du vasospasme post-hémorragie sous-arachnoïdienne en angiotomodensitométrie
Objective: To review the literature on and assess the intra- and inter-observer reliability of computed tomography angiography (CTA) in the screening or diagnosis of cerebral vasospasm (CV) following subarachnoid hemorrhage (SAH). Methods: Articles reporting the reliability of CTA up to May 2018 were systematically searched and evaluated. Eleven raters independently graded 17 arterial segments in each of 50 SAH patients for the presence of vasospasm using a 4-category scale. Furthermore, readers were asked: to judge the presence or absence of any moderate/severe vasospasm (≥ 50 % narrowing); whether findings would justify augmentation of medical treatment; and/or DSA with/without angioplasty. Four raters reassessed the same patients in different order at least 4 weeks later. Results: The systematic review revealed that the reliability of CTA had not previously been rigorously assessed. The intra-rater reliability reached a substantial level (k > 0.600) in 3/4 readers for the detection of moderate-severe vasospasm, but inter-rater reliability remained below substantial even when results were stratified according to specialty and experience. There was less than substantial agreement for imaging-based recommendations (medical management or indications to proceed with DSA/angioplasty). Dichotomized per segment results (presence or absence of >50% narrowing) allowed reaching substantial agreement only among senior readers evaluating M1 segments. Excluding cases in which segments were obscured by metal artifacts did not allow additional arterial segments to reach the threshold for substantial agreement. Conclusion: CTA was not sufficiently repeatable among observers diagnosing CV to support a general use in guiding decisions in the clinical management of SAH patients.
Cerebrovascular Disorders Cerebral Vasospasm Stroke Subarachnoid Hemorrhage Computed Tomography Angiography Digital Subtraction Angiography