title: The Revascularization Scales Dilemma: Is It Right to Apply the Treatment in Cerebral Ischemia Scale in Posterior Circulation Stroke?
abstract: OBJECTIVE
  Although various revascularization scales are used in the angiographic evaluation of acute ischemic stroke, observer reliability tests of these scales have been rarely performed for posterior circulation stroke. We aimed to evaluate inter- and intraobserver variability of 2 scales, the modified Treatment in Cerebral Ischemia and the Arterial Occlusive Lesion, in posterior circulation stroke.
  
  
  METHODS
  Three independent readers interpreted pre- and postthrombolytic angiographies of 62 patients with posterior circulation stroke by using the modified Treatment in Cerebral Ischemia and Arterial Occlusive Lesion scales. The κ statistic was used to measure observer agreement for both scales, and κ > 0.6 was considered substantial agreement.
  
  
  RESULTS
  For the Arterial Occlusive Lesion scale, inter- and intraobserver agreement was >0.6. While intraobserver agreement of the modified Treatment in Cerebral Ischemia scale was >0.6 except for 1 reader, interobserver agreement was lower in dichotomized and original scales. In 49 cases with solely basilar artery occlusion, inter- and intraobserver agreement of both scales was similar to that in all 62 patients with posterior circulation stroke. In 2 consecutive readings, there was a significant decrease in the proportion of mTICI 2a reads (22.58% in the first versus 13.44% in the second session, P < .03) and a reciprocal increase in the sum of proportions for modified Treatment in Cerebral Ischemia 2b and modified Treatment in Cerebral Ischemia 3 reads (62.37% in the first versus 72.58% in the second session, P < .046).
  
  
  CONCLUSIONS
  In angiographic assessment of posterior circulation stroke, inter- and intraobserver agreement for the Arterial Occlusive Lesion scale was reliable, while the modified Treatment in Cerebral Ischemia failed to achieve substantial interobserver agreement. The clinical impact of this result needs to be validated in future studies.
authors.affiliation: From the Department of Radiology (C.J., B.S.C., J.H.K.), Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: C
authors.identifier: http://orcid.org/0000-0002-8862-7347
authors.initials: C
authors.lastname: Jung
authors.affiliation: Department of Radiology (W.Y.), Chonnam National University Medical School, Gwangju, Korea.
authors.forename: W
authors.identifier: http://orcid.org/0000-0002-8598-3127
authors.initials: W
authors.lastname: Yoon
authors.affiliation: Department of Radiology (S.J.A., S.H.S.), Gangnam Severance Hospital, Yonsei University, Seoul, Korea.
authors.forename: S J
authors.identifier: http://orcid.org/0000-0003-0075-2432
authors.initials: SJ
authors.lastname: Ahn
authors.affiliation: From the Department of Radiology (C.J., B.S.C., J.H.K.), Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: B S
authors.identifier: http://orcid.org/0000-0001-6310-1798
authors.initials: BS
authors.lastname: Choi
authors.affiliation: From the Department of Radiology (C.J., B.S.C., J.H.K.), Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: J H
authors.identifier: http://orcid.org/0000-0002-0545-4138
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Radiology (S.J.A., S.H.S.), Gangnam Severance Hospital, Yonsei University, Seoul, Korea Severance Institute of Vascular and Metabolic Research (S.H.S.), Yonsei University College of Medicine, Seoul, Korea. suhsh11@yuhs.ac.
authors.forename: S H
authors.identifier: http://orcid.org/0000-0002-7098-4901
authors.initials: SH
authors.lastname: Suh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000628:therapy; D002533:Cerebral Angiography; D002548:Cerebral Revascularization; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D020521:Stroke / Q000000981:diagnostic imaging* / Q000628:therapy; D015912:Thrombolytic Therapy