Evaluation of the Accuracy Equivalence of Head CT Interpretations in Acute Stroke Patients Using a Smartphone, a Laptop, or a Medical Workstation

Abstract

Purpose: To evaluate and compare the clinical performance of observers interpreting head CT images from patients with symptoms of acute stroke with a medical workstation or a smartphone or laptop reading system.Materials and methods: Our institutional review board approved this retrospective study and waived the requirement for informed consent. We employed a factorial design including 2,256 interpretations (188 patients  4 neuroradiologists  3 reading systems). Accuracy equivalence tests, at a threshold of 5% and 10%, were performed for the following variables: detection of imaging contraindications for intravenous recombinant tissue-type plasminogen activator administration (eg, hemorrhagic lesions), ischemic lesions, hyperdense arteries, and acute ischemic lesions. For each clinical variable, the sensitivity, specificity, and receiver operating characteristic (ROC) curves were evaluated.Results: For each variable, the shapes of the ROC curves were very similar for all of the reading systems, indicating similar observer performance with different specificities and sensitivities. For all the clinical variables, the areas under the ROC curves were equivalent for all of the reading systems at a 10% threshold and were equivalent at a 5% threshold for hemorrhagic lesions, hyperdense middle cerebral artery, and acute ischemic lesion in the middle cerebral artery territory. There was no more than 30 seconds of difference between the reading time of the mobile devices compared with that for the medical workstation. Conclusion:The results of this pilot study showed equivalent diagnostic accuracy when using smartphone and laptops compared with medical monitors to interpret head CT images of patients with symptoms of acute stroke.

Reliability and accuracy of individual Alberta Stroke Program Early CT Score regions using a medical and a smartphone reading system in a telestroke network

“…Detection of haemorrhagic lesions, hyperdense MCA, ischaemic lesions in the MCA territory, acute ischaemic lesion in the MCA territory, and ASPECTS <6, in head NCCTs using a smartphone were previously evaluated by our group. High levels of reliability and accuracy were found, 6,14 except for ASPECTS < 6. In the current article, we focused on the evaluation of individual ASPECTS regions to detect those specific territories that significantly increase interrater reliability influencing the overall and dichotomised ASPECTS scores.…”

“…However, in a previous analysis dichotomised ASPECTS scores showed conflicting results. 6 ASPECTS < 6 is a well-known contraindication to IV rtPA administration. Hence, when using a smartphone, lesions involving the internal capsule, insula and M2 regions should be carefully evaluated every time that treatment decisions are made based on dichotomised ASPECTS scores.…”

“…However, equivalence between the two reading systems was achieved at 7.9%. 6 These results may constitute an additional risk when ruling out contraindications for IV rtPA administration, while using a smartphone device. Hence, improvement in the detection of lesions in the three aforementioned territories will end up in more accurate total and dichotomised ASPECTS scores.…”

“…A complete description on how to perform dichotomised ASPECTS evaluation can be found elsewhere. 6 Herein, we present a full description on individual ASPECTS regions and its corresponding functional anatomy.…”

“…1,2,4,5 In order to increase the availability of neuroradiologists, and to improve reading times, mobile solutions based on computer tablets, laptops and smartphones have been recently evaluated. [6][7][8] Literature has been published analysing dichotomised ASPECTS scores but not individual ASPECTS regions using mobile solutions. One study has focused on differences in individual ASPECTS regions between head NCCT scans and other diagnostic modalities, such as head CT angiography (CTA) and CT perfusion (CTP).…”