Performance of e-ASPECTS software in comparison to that of stroke physicians on assessing CT scans of acute ischemic stroke patients

• Published in: International journal of stroke 2016-06, Vol.11 (4), p.438-445
• Main Authors: Herweh, Christian, Ringleb, Peter A, Rauch, Geraldine, Gerry, Steven, Behrens, Lars, Möhlenbruch, Markus, Gottorf, Rebecca, Richter, Daniel, Schieber, Simon, Nagel, Simon
• Format: Article
• Language: English
• Subjects: Alberta; Brain Ischemia - diagnostic imaging; Clinical Competence; Diagnostic Errors; Diffusion Magnetic Resonance Imaging; Humans; Machine Learning; Pattern Recognition, Automated; Physicians; Prospective Studies; Retrospective Studies; ROC Curve; Software; Stroke - diagnostic imaging; Time Factors; Tomography, X-Ray Computed
• ISSN: 1747-4930; 1747-4949
• DOI: 10.1177/1747493016632244

Background The Alberta Stroke Program Early CT score (ASPECTS) is an established 10-point quantitative topographic computed tomography scan score to assess early ischemic changes. We compared the performance of the e-ASPECTS software with those of stroke physicians at different professional levels. Methods The baseline computed tomography scans of acute stroke patients, in whom computed tomography and diffusion-weighted imaging scans were obtained less than two hours apart, were retrospectively scored by e-ASPECTS as well as by three stroke experts and three neurology trainees blinded to any clinical information. The ground truth was defined as the ASPECTS on diffusion-weighted imaging scored by another two non-blinded independent experts on consensus basis. Sensitivity and specificity in an ASPECTS region-based and an ASPECTS score-based analysis as well as receiver-operating characteristic curves, Bland–Altman plots with mean score error, and Matthews correlation coefficients were calculated. Comparisons were made between the human scorers and e-ASPECTS with diffusion-weighted imaging being the ground truth. Two methods for clustered data were used to estimate sensitivity and specificity in the region-based analysis. Results In total, 34 patients were included and 680 (34 × 20) ASPECTS regions were scored. Mean time from onset to computed tomography was 172 ± 135 min and mean time difference between computed tomographyand magnetic resonance imaging was 41 ± 31 min. The region-based sensitivity (46.46% [CI: 30.8;62.1]) of e-ASPECTS was better than three trainees and one expert (p ≤ 0.01) and not statistically different from another two experts. Specificity (94.15% [CI: 91.7;96.6]) was lower than one expert and one trainee (p