Evaluation of quantified contrast-enhanced color and power Doppler ultrasonography for the assessment of vascularity and perfusion of naturally occurring tumors in dogs.
OBJECTIVE
To investigate subjective and computerized methods of evaluation of color Doppler (CD) and power Doppler (PD) ultrasonographic images (obtained before and after administration of contrast medium) for quantitative assessment of vascularity and perfusion of various naturally occurring tumors in dogs.


METHODS
34 tumors in 34 dogs.


METHODS
Tumors in dogs were examined via CD and PD ultrasonography before and after i.v. injection of a microbubble contrast agent (pre- and postcontrast examinations, respectively). Images were digitized for subjective assessment of vessel density and vascular pattern and computer-aided assessment of parameters of vascularity (fractional area [FA]) and perfusion (color-weighted FA [CWFA] and mean color-weighted FA [CWFA] and mean color level).


RESULTS
With both analysis methods, more vessels were identified in precontrast PD ultrasonographic images than in precontrast CD ultrasonographic images. Moreover, compared with values for precontrast PD ultrasonography, FA, CWFA, and mean color level were higher for postcontrast PD ultrasonography. In postcontrast images, there was a significant association between vessel densities determined through subjective and computerized assessments. Although sample size was small, vascularity of squamous cell carcinomas was significantly greater than that of other tumor types. Ten of the 19 softer than issue that sarcomas had low vessel density with minor contrast enhancement. With increasing gross tumor volume, FA and CWFA decreased for all Doppler ultrasonographic methods.


CONCLUSIONS
Higher values of the ultrasonographic parameters representing vascularity and perfusion of tumors in dogs were determined via PD ultrasonography after administration of contrast medium than via PD or CD ultrasonography without administration of contrast medium.
Schärz
Myriam
M
Section of Diagnostic Imaging and Radio-Oncology, Vetsuisse-Faculty, University of Zürich, 8057 Zürich, Switzerland.
Ohlerth
Stefanie
S
Achermann
Roger
R
Gardelle
Olivier
O
Roos
Malgorzata
M
Saunders
H Mark
HM
Wergin
Melanie
M
Kaser-Hotz
Barbara
B
D000818:Animals; D003287:Contrast Media; D004283:Dog Diseases / Q000000981:diagnostic imaging*; D004285:Dogs; D005260:Female; D008297:Male; D009369:Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging / Q000662:veterinary*; D018608:Ultrasonography, Doppler / Q000379:methods* / Q000662:veterinary; D018615:Ultrasonography, Doppler, Color / Q000662:veterinary
D003287:Contrast Media