Computed tomographic and magnetic resonance imaging features of canine segmental caudal vena cava aplasia.
OBJECTIVE
To describe the computed tomographic and magnetic resonance imaging features of segmental caudal vena cava aplasia and associated vascular anomalies in dogs.


METHODS
A retrospective study was performed reviewing computed tomographic and magnetic resonance imaging archives of eight institutions for dogs with segmental caudal vena cava aplasia. Inclusion criteria included a computed tomographic or magnetic resonance imaging study and supportive diagnostic and follow-up information. Abdominal vessels were reviewed for size, shape, location and course (including tributaries and branches) and classified as normal, abnormal or shunt vessels.


RESULTS
Ten dogs with segmental caudal vena cava aplasia were identified. In all dogs, postrenal caval blood was shunted to either a right or a left azygos vein, with seven different angiographic patterns. Affected dogs were predominantly female (70 per cent) and young (mean 2.6 years). Additional portocaval and porto-azygos shunt vessels were identified in two cases each. Computed tomographic angiography and magnetic resonance angiography depicted details of abdominal vessels including thrombus formation in one dog.


CONCLUSIONS
Segmental caudal vena cava aplasia is a vascular congenital anomaly in the dog that can be associated with thrombosis and portosystemic shunts. Computed tomographic angiography and magnetic resonance angiography are excellent tools to demonstrate the complex vascular anatomy and to guide treatment planning for portosystemic shunts and thrombolytic therapy.
Schwarz
T
T
Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI 537064, USA.
Rossi
F
F
Wray
J D
JD
Ablad
B
B
Beal
M W
MW
Kinns
J
J
Seiler
G S
GS
Dennis
R
R
McConnell
J F
JF
Costello
M
M
D000792:Angiography / Q000662:veterinary*; D000818:Animals; D001401:Azygos Vein / Q000002:abnormalities*; D004283:Dog Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging; D004285:Dogs / Q000002:abnormalities*; D005260:Female; D008279:Magnetic Resonance Imaging / Q000662:veterinary*; D008297:Male; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000662:veterinary*; D014652:Vascular Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000662:veterinary; D014682:Vena Cava, Inferior / Q000002:abnormalities*