title: Characterization of triple-phase computed tomography in dogs with pancreatic insulinoma.
abstract: Little information is available regarding triple-phase computed tomography (CT) of canine pancreatic insulinoma. A few case reports with small numbers of cases have indicated that hyper-attenuation in the arterial phase was a common finding on multi-phasic CT in dogs with insulinoma. Our purpose was to clarify the characteristic findings of dogs with insulinoma on triple-phase CT. Nine dogs with insulinoma that underwent triple-phase CT were included in the present study. Attenuation patterns in the arterial phase indicated hypo-attenuation in 4 cases and hyper-attenuation in 2 cases. In the remaining 3 cases, 1 case showed hypo-attenuation and 1 case showed hyper-attenuation in the pancreatic phase, and 1 case presented hyper-attenuation in the later phase. Altogether, 5 cases showed hypo and 4 cases showed hyper-attenuation in at least one phase. The enhancement pattern was homogenous in 7 cases and heterogeneous in 2 cases. Tumor margins were well-defined in 5 cases and ill-defined in 4 cases. Capsule formation was present in 5 cases and absent in 4 cases. In conclusion, it is important to note that hypo-attenuation was as common as hyper-attenuation in dogs with insulinoma in triple-phase CT in at least one phase. Additionally, mass lesions were most conspicuous not only in the arterial phase but in the pancreatic and later phases in some cases. Therefore, it is important to perform triple-phase CT and notice about variable findings for the detection of canine pancreatic insulinoma.
authors.affiliation: Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Fukushima
authors.forename: Reina
authors.initials: R
authors.lastname: Fujiwara
authors.forename: Kie
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kanemoto
authors.forename: Koichi
authors.initials: K
authors.lastname: Ohno
authors.forename: Masaya
authors.initials: M
authors.lastname: Tsuboi
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Uchida
authors.forename: Naoaki
authors.initials: N
authors.lastname: Matsuki
authors.forename: Ryohei
authors.initials: R
authors.lastname: Nishimura
authors.forename: Hajime
authors.initials: H
authors.lastname: Tsujimoto
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000000981:diagnostic imaging*; D004285:Dogs; D007340:Insulinoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000662:veterinary*