Diagnostic Utility of Computed Tomography Perfusion in the Telestroke Setting

Abstract

Background: Definitive diagnosis of acute ischemic stroke is challenging, particularly in telestroke settings. Although the prognostic utility of CT perfusion (CTP) has been questioned, its diagnostic value remains under-appreciated, especially in cases without an easily visible intracranial occlusion. We assessed the diagnostic accuracy of routine CTP in the acute telestroke setting. Methods: Acute and follow-up data collected prospectively from consecutive suspected patients with stroke assessed by a state-wide telestroke service between March 2020 and August 2021 at 12 sites in Australia were analyzed. All patients in the final analysis had been assessed with multimodal CT, including CTP, which was post-processed with automated volumetric software. Diagnostic sensitivity and specificity were calculated for multimodal CT and each individual component (noncontrast CT [NCCT], CT angiogram [CTA], and CTP). Final diagnosis determined by consensus review of follow-up imaging and clinical data was used as the reference standard. Results: During the study period, complete multimodal CT examination was obtained in 831 patients, 457 of whom were diagnosed with stroke. Diagnostic sensitivity for ischemic stroke increased by 19.5 percentage points when CTP was included with NCCT and CTA compared with NCCT and CTA alone (73.1% positive with NCCT+CTA+CTP [95% CI, 68.8–77.1] versus 53.6% positive with NCCT+CTA alone [95% CI, 48.9–58.3], P <0.001). No difference was observed between specificities of NCCT+CTA and NCCT+CTA+CTP (98.7% [95% CI, 98.5–100] versus 98.7% [95% CI, 96.9–99.6], P =0.13). Multimodal CT, including CTP, demonstrated the highest negative predictive value (75.0% [95% CI, 72.1–77.7]). Patients with stroke not evident on CTP had small volume infarcts on follow-up (1.2 mL, interquartile range 0.5–2.7mL). Conclusions: Acquisition of CTP as part of a telestroke imaging protocol permits definitive diagnosis of cerebral ischemia in 1 in 5 patients with normal NCCT and CTA.

TACTICS VR Stroke Telehealth Virtual Reality Training for Health Care Professionals Involved in Stroke Management at Telestroke Spoke Hospitals: Module Design and Implementation Study

“…It is a collaboration between the Prince of Wales Hospital, eHealth NSW, the NSW Agency for Clinical Innovation (ACI), and the NSW Ministry of Health in partnership with the Australian Stroke Foundation. The NSW Telestroke Service was rolled out progressively to its total coverage, with the final sites activated in June 2022, providing services to 23 rural hospitals across NSW [41].…”

Diagnostic accuracy of large and medium vessel occlusions in acute stroke imaging by neurology residents and stroke fellows: A comparison of CT angiography alone and CT angiography with CT perfusion

“…It was also noticed in a recent study that including CTP as part of a telestroke imaging protocol was associated with a definitive diagnosis of acute ischemic stroke in approximately one in five cases where NCCT and CTA were nondiagnostic. 28 Our study provides some common reasons that trainees miss stroke-related arterial occlusions (Figure 1). For example, such occlusions were most common in the PCA and M2 territories.…”

“…It was also noticed in a recent study that including CTP as part of a telestroke imaging protocol was associated with a definitive diagnosis of acute ischemic stroke in approximately one in five cases where NCCT and CTA were nondiagnostic. 28…”

Tenecteplase versus alteplase for stroke thrombolysis evaluation (TASTE): A multicentre, prospective, randomized, open-label, blinded-endpoint, controlled phase III non-inferiority trial protocol

“…The selection of patients with perfusion imaging builds on previous imaging selected tenecteplase trials which demonstrated the improved biological mechanisms of tenecteplase over alteplase and supports the trial where only confirmed ischemic strokes are enrolled to reduce the trial mimic rate seen on other phase III trials 6,7 to support definitive diagnosis. 14 The TASTE study excludes patients with planned endovascular treatment, an important consideration where the treatment effect of endovascular thrombectomy is likely to be larger than thrombolysis. Thrombolysis remains critical in stroke management where endovascular therapy is currently only recommended for patients with an LVO (accounting for 14–20% of all ischemic stroke), especially as bridging thrombolysis pre-endovascular therapy remains standard of care.…”