title: Delayed-phase CT angiography is superior to arterial-phase CT angiography at localizing occlusion sites in acute stroke patients eligible for intra-arterial reperfusion therapy.
abstract: We compared the accuracy for localizing arterial occlusion sites between delayed-phase computed tomography angiography (CTA) and arterial-phase CTA in acute stroke patients with large vessel occlusion. Institutional Review Board approval was obtained, and informed consent was waived. For patients treated with intra-arterial thrombolysis within a 6 hour window between January 2009 and November 2011, we retrospectively assessed the arterial occlusion sites of pre-treatment, delayed-phase and arterial-phase CTA and compared these with digital subtraction angiography (DSA) findings. The positive predictive value for detection of vessel occlusion for both CTA methods was derived using DSA as a reference standard. The outcomes were compared using the McNemar test. Inter-observer disagreement within each modality was assessed using the Kendall W test. Among 73 patients treated with intra-arterial thrombolysis, 24 (32.9%) underwent both arterial-phase and delayed-phase CTA, and 66 (90.4%) underwent arterial-phase CTA only. For 24 patients undergoing both arterial-phase and delayed-phase CTA, the delayed-phase CTA detected concordant occlusion sites with DSA in 21 patients, yielding a positive predictive value of 87.5%, whereas the arterial-phase CTA detected this in 14 patients, for a positive predictive value of 58.3% (p=0.013). When discordant with DSA, arterial-phase or delayed-phase CTA indicated occlusions in more proximal sites than DSA. Delayed-phase CTA more precisely localized the occlusion site than arterial-phase CTA in acute stroke patients with large vessel occlusion. Thus, delayed-phase CTA findings could guide neurointerventionists in selecting intra-arterial thrombolysis modalities.
authors.affiliation: Department of Radiology, Ilsan Paik Hospital, Inje University School of Medicine, 2240, Daehwa-dong, Ilsanseo-gu, Goyang-si, Gyeonggi-do 411-706, Republic of Korea.
authors.forename: Ho Jin
authors.initials: HJ
authors.lastname: Chung
authors.affiliation: Department of Radiology, Ilsan Paik Hospital, Inje University School of Medicine, 2240, Daehwa-dong, Ilsanseo-gu, Goyang-si, Gyeonggi-do 411-706, Republic of Korea. Electronic address: hoonbeer@hanmail.net.
authors.forename: Byung Hoon
authors.initials: BH
authors.lastname: Lee
authors.affiliation: Department of Radiology, Ilsan Paik Hospital, Inje University School of Medicine, 2240, Daehwa-dong, Ilsanseo-gu, Goyang-si, Gyeonggi-do 411-706, Republic of Korea.
authors.forename: Yoon Joon
authors.initials: YJ
authors.lastname: Hwang
authors.affiliation: Department of Radiology, Ilsan Paik Hospital, Inje University School of Medicine, 2240, Daehwa-dong, Ilsanseo-gu, Goyang-si, Gyeonggi-do 411-706, Republic of Korea.
authors.forename: Su Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Radiology, Ilsan Paik Hospital, Inje University School of Medicine, 2240, Daehwa-dong, Ilsanseo-gu, Goyang-si, Gyeonggi-do 411-706, Republic of Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Radiology, Ilsan Paik Hospital, Inje University School of Medicine, 2240, Daehwa-dong, Ilsanseo-gu, Goyang-si, Gyeonggi-do 411-706, Republic of Korea.
authors.forename: You Sung
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Department of Neurology, Ilsan Paik Hospital, Inje University School of Medicine, Goyang-si, Gyeonggi-do, Republic of Korea.
authors.forename: Keun-Sik
authors.initials: KS
authors.lastname: Hong
authors.affiliation: Department of Neurology, Ilsan Paik Hospital, Inje University School of Medicine, Goyang-si, Gyeonggi-do, Republic of Korea.
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Cho
authors.affiliation: Department of Neurology, Ilsan Paik Hospital, Inje University School of Medicine, Goyang-si, Gyeonggi-do, Republic of Korea.
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Park
mesh_terms: D000368:Aged; D015901:Angiography, Digital Subtraction; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D002533:Cerebral Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015424:Reperfusion / Q000379:methods; D015203:Reproducibility of Results; D012189:Retrospective Studies; D020521:Stroke / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000601:surgery; D025321:Surgery, Computer-Assisted / Q000379:methods; D015912:Thrombolytic Therapy; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Acute ischemic stroke; Arterial phase; Computed tomography angiography (CTA); Delayed phase; Intra-arterial thrombolysis; Large vessel occlusion