title: CT during arterial portography: diagnostic pitfalls.
abstract: Computed tomography (CT) during arterial portography (CTAP) is an important technique for evaluating the liver before hepatic tumor resection. With this technique, most tumors are of low attenuation compared with that of enhancing parenchyma. At times, low-attenuation lesions are encountered that represent perfusion abnormalities rather than tumor deposits. These perfusion abnormalities can be categorized as (a) those resulting from improper technique; (b) those extending from hilum to capsule (straight-line sign), with or without an obstructing mass; (c) perihilar and periligamentous abnormalities; (d) subcapsular defects (linear or wedge shaped); and (e) those seen with cirrhosis or regenerating nodules. Adjuvant use of delayed CT, magnetic resonance imaging, and intraoperative ultrasound aids in characterization of these nontumorous defects, thereby improving specificity. The authors conclude that when potential candidates are evaluated for hepatic tumor resection, knowledge of the existence of the various diagnostic pitfalls of CTAP and their imaging characteristics is imperative to avoid inadvertent false results.
authors.affiliation: Department of Radiology, Emory University Hospital, Atlanta, GA 30322.
authors.forename: R C
authors.initials: RC
authors.lastname: Nelson
authors.forename: G H
authors.initials: GH
authors.lastname: Thompson
authors.forename: J L
authors.initials: JL
authors.lastname: Chezmar
authors.forename: R K
authors.initials: RK
authors.lastname: Harned
authors.forename: M P
authors.initials: MP
authors.lastname: Fernandez
mesh_terms: D015901:Angiography, Digital Subtraction; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000000981:diagnostic imaging*; D015179:Colorectal Neoplasms / Q000473:pathology; D005188:False Negative Reactions; D005189:False Positive Reactions; D006499:Hepatic Artery / Q000000981:diagnostic imaging*; D006801:Humans; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000556:secondary; D011172:Portography; D011300:Preoperative Care; D014057:Tomography, X-Ray Computed