Diagnosis of recanalization of the intracranial artery has poor inter-rater reliability

Abstract

Background and purpose: Recanalization is the important outcome measure for acute stroke therapy. Several methods of recanalization assessment are used in clinical practice, but few studies have addressed their reliability. We, therefore, sought to assess interobserver reliability of the diagnosis of intracranial artery recanalization following intervention by using TIMI criteria.

Materials and methods: The digital angiography scans of all patients with acute ischemic stroke during 2009 undergoing DSA and endovascular procedures at Ostrava University Hospital were assessed in the study. Images were retrospectively evaluated for intracranial artery recanalization on the TIMI scale by 2 experienced neuroradiologists who were blinded to clinical findings and to each other.

Results: The angiography scans of 43 patients (16 females; age, 70.5 ± 14 years; median baseline NIHSS score, 15 [IQR, 11-18]) were retrospectively evaluated in our study. At 3 months, 27% of patients had mRS scores ≤ 2 and mortality was 18%. Two radiologists diagnosed TIMI grades as follows: TIMI 0, 16%, and 16%; TIMI 1, 21%, and 8%; TIMI 2a, 32% and 29%; TIMI 2b, 13% and 16%; TIMI 3, 18, and 31%. Interobserver agreement for recanalization was weighted κ = 0.4 (95% CI, 0.2-0.6).

Conclusions: The diagnosis of recanalization after interventional procedures was found to have poor interobserver agreement between 2 experienced neuroradiologists. TIMI criteria, therefore, do not permit reliable comparison of the efficacy of recanalization therapy among different studies.