Analysis of Advanced Imaging Utilization in Low National Institutes of Health Stroke Scale Score and Rate of Large Vessel Occlusion Detection in Large Telestroke Database
Theresa Sevilis1, Mariecken Fowler1, Amanda Avila1, Caitlyn Boyd1, Oleg Collins2, Lan Gao2, Gregory Heath3, Thomas Devlin4
1TeleSpecialists, LLC, 2Mathematics, University of Tennessee Chattanooga, 3University of Tennessee, 4Neurology, University of Tennessee Health Science Center
Objective:
Analyze the rate of large vessel occlusion (LVO) detection in low National Institutes of Health Stroke Scale (NIHSS) score patients in a large multicenter database.
Background:

The benefits of mechanical thrombectomy in low NIHSS score (<6) is unclear and undergoing investigation. Currently, great variation exists in practice patterns of computed tomography angiography (CTA) for patients with low NIHSS. Current guidelines do not address low NIHSS largely owing to a paucity of data. Better understanding of the rate of LVO associated with low NIHSS could help guide clinical practice and pave the way for expanding guideline recommendations.

Design/Methods:

Acute stroke consultations seen in the emergency department in 227 facilities (27 states) from July 1, 2021 to December 31, 2021 were extracted from the TeleCareTM database. The encounters seen within 24 hours of last known normal were reviewed for CTA performed, LVO detected, and NIHSS score. Multivariate analysis was performed to determine the odds ratio (OR) for CTA performed, and LVO found at each NIHSS score of 0-5 with reference of ≥6.

Results:

23,166 acute stroke encounters were included and 10,507 had CTA performed. There were lesser odds for CTA being performed among patients with an NIHSS of: 0 (OR=0.14, [0.13,0.15]); 1 (OR=0.16, [0.15,0.18]); 2 (OR=0.27, [0.24,0.3]); 3 (OR=0.33, [ 0.3,0.37]); 4 (OR=0.49, [0.43,0.55]); and 5 (OR=0.71, [0.61,0.82]). In addition, there were lesser odds of an LVO detected among patients with an NIHSS of: 0 (OR=0.1, [0.07,0.13]); 1 (OR=0.09, [0.06,0.12]); 2 (OR=0.16, [0.12,0.22]); 3 (OR=0.14, [0.1,0.2]); 4 (OR=0.24, [0.18,0.32]), and 5 (OR=0.27, [0.2,0.37]).

Conclusions:

Analysis of our large telemedicine database demonstrated a significant number of LVOs detected with NIHSS <6, supporting lowering the minimum NIHSS score for emergent CTA. The cutoff of ≥4 may be optimal threshold for LVO capture. We suggest a rational approach to CTA performance to include patients with NIHSS ≥4 or cortical symptoms.

10.1212/WNL.0000000000202050