Biology Reference
In-Depth Information
At peak liver enhancement, both hydropic degenerations were slightly hypoechoic
to the surrounding hepatic tissue. During the portal phase, they both appeared
isoechoic to the surrounding tissue (data media: P: 52.1%, TTP: 54 s, RBF: 66.9,
MTT: 96 s; surrounding tissue: P: 53.4%, TTP: 53.9 s, RBF: 65.8, MTT: 94.9 s).
Cystic hepatic lesions always appeared anechoic during the arterial and portal
phases. The collected data relative to the eosinophilic infiltrate were similar to
the data of the surrounding tissue (data collected for the nodular lesion: P: 43.6%,
TTP: 31.8 s, RBF: 59, MTT: 66.2 s; surrounding tissue: P: 40.4%, TTP: 38.6 s,
RBF: 52.6, MTT: 65.2 s). Among the hepatocellular carcinomas, three were
hyperechoic during the arterial blood phase (two dishomogeneous and one homo-
geneous) and one was hypoechoic. At peak liver enhancement, three were
hypoechoic and one was isoechoic to the surrounding hepatic tissue. All appeared
hypoechoic during the portal blood phase (data media: P: 28.6%, TTP: 73.4 s, RBF:
36.7, MTT: 54.1 s; surrounding hepatic tissue: P: 78%, TTP: 49.3 s, RBF: 42.6,
MTT: 92.6 s). Biliary carcinoma was hyperechoic during the arterial blood phase
and hypoechoic at peak liver enhancement and during the portal blood phase (data
media: P: 44.8%, TTP: 30.4 s, RBF: 59.8, MTT: 58.2 s; surrounding hepatic tissue:
P: 50.4%, TTP: 47 s, RBF: 66, MTT: 85.4 s). The lymphoma was isoechoic during
the arterial blood phase and hypoechoic at peak liver enhancement and during the
portal blood phase (data media: P: 29.8%, TTP: 31.7 s, RBF: 34.8, MTT: 44.6 s;
surrounding hepatic tissue: P: 36.5%, TTP: 73.6 s, RBF: 44.4, MTT: 105.7 s).
Significant differences between the ultrasonographic features of the benign/malig-
nant lesions during the arterial blood phase and at peak liver intensity were not
observed. A statistically significant difference in echogenicity during the portal
blood phase of the benign and malign nodular hepatic lesions was described. All
malignant lesions were hypoechoic during the portal and late phase as, with the
exception of the simple cysts, all the benign lesions were hyper/isoechoic to the
surrounding hepatic tissue. The hypoechogenicity during the portal phase, as an
important feature for the discrimination between benign and malignant hepatic
nodular lesions, showed a sensitivity and specificity, respectively, of 100% (CI
95%: 100-100) and of 70% (CI 95%: 41.6-98.4), for a positive predictive value of
66.7% (CI 95%: 35.9-97.5) and a negative predictive value of 100% (CI 95%:
100-100).
18.4 Discussion
CEUS is routinely employed in human medicine to detect and characterize focal
hepatic lesions (Quaia
2007
). The most significant feature of malignancy is
hypoechogenicity during the portal phase, possibly due to new arterial blood supply
associated with a concomitant reduction of portal blood vessels (Ziegler et al.
2003
;
Quaia
2007
). In veterinary medicine, CEUS has been widely employed for the
characterization of hepatic lesions in the dog (O'Brien et al.
2004
; Ivan
ˇ
i
´
et al.
2009
; O'Brien
2007
; Volta et al.
2009
) as few studies have been done in the cat
