title: Validation of ultrasound parameters to assess collateral flow via ophthalmic artery in internal carotid artery occlusion.
abstract: This study aimed to characterize the flow patterns using ultrasound (US) in the external carotid artery (ECA) in patients with total occlusion of internal carotid artery (ICA) and characterize collateral retrograde flow through the ophthalmic artery (OA, secondary collateral, internalization). This study was performed on 45 patients who were retrospectively selected with total occlusion of the ICA, who underwent digital subtraction angiography (DSA), magnetic resonance angiography (MRA), and US (43 men; mean age 68.1 ± 7.9 years). Collateral retrograde flow and collateral flow through the circle of Willis (primary collateral) were determined by DSA and MRA. We compared several US parameters such as ECA peak systolic velocity, mean velocity, end-diastolic (ED) velocity, pulsatility index (PI), and pulsatility transmission index (PTI). PTI was defined as the ratio of ipsilateral ECA PI to the ipsilateral common carotid artery (CCA). In this patient group, 27 patients showed retrograde flow through OA as assessed by DSA. The presence of primary collateral flow was significantly lower in patients with retrograde flow than without (P < .05). ECA ED velocity was significantly higher, and PI and PTI were significantly lower with retrograde flow through OA than without (P < .05). According to receiver operating characteristic analysis, PTI was the most highly correlated ultrasonologic parameter with internalization (cutoff value, .94; sensitivity, 92.6%; specificity, 94.5%). Using PTI was discriminative to determine internalization of ECA because a collateral pathway through OA in cases of ICA occlusion had less primary collateral pathways.
authors.affiliation: Division of Neurology, Department of Stroke and Cerebrovascular Diseases, Research Institute National Cerebral and Cardiovascular Center, Osaka, Japan. Electronic address: tanakat@hsp.ncvc.go.jp.
authors.forename: Tomotaka
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Division of Neurology, Department of Stroke and Cerebrovascular Diseases, Research Institute National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Doijiri
authors.affiliation: Division of Neurology, Department of Stroke and Cerebrovascular Diseases, Research Institute National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Kozue
authors.initials: K
authors.lastname: Saito
authors.affiliation: Division of Neurology, Department of Stroke and Cerebrovascular Diseases, Research Institute National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Katsufumi
authors.initials: K
authors.lastname: Kajimoto
authors.affiliation: Division of Neurology, Department of Stroke and Cerebrovascular Diseases, Research Institute National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Ihara
authors.affiliation: Division of Neurology, Department of Stroke and Cerebrovascular Diseases, Research Institute National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamagami
authors.affiliation: Division of Neurology, Department of Stroke and Cerebrovascular Diseases, Research Institute National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Miyashita
authors.affiliation: Division of Neurology, Department of Stroke and Cerebrovascular Diseases, Research Institute National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Nagatsuka
mesh_terms: D000368:Aged; D015901:Angiography, Digital Subtraction; D019540:Area Under Curve; D002342:Carotid Artery, External / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016893:Carotid Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D002941:Circle of Willis / Q000000981:diagnostic imaging / Q000503:physiopathology; D003097:Collateral Circulation; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D009880:Ophthalmic Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011237:Predictive Value of Tests; D012372:ROC Curve; D012039:Regional Blood Flow; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014463:Ultrasonography
keywords: Carotid artery occlusion; carotid ultrasound; collateral circulation; ophthalmic artery; pulsatility transmission index