Accuracy of ultrasound in the detection of liver fibrosis in chronic viral hepatitis.
OBJECTIVE
To assess the accuracy of ultrasonography (US) in the identification and grading of hepatic fibrosis in patients afflicted with chronic viral liver disease, compared to histological examination as a gold standard.


METHODS
We prospectively studied 105 patients (32 F, 73 M) affected by chronic viral liver disease in 36 months. Patients were studied with B-mode US and then underwent US-guided liver biopsy. All the patients were studied with conventional US with a Sequoia 512, 6.0 (Acuson, Mountain View CA, USA). We evaluated the following US parameters: liver margins, parenchymal echotexture, portal vein caliber and spleen diameter. The four B-mode US parameters were used for the US grading (from 0 to 4). Scheuer's grading (from 0 to 4) was used for the histological score. Grades 3 and 4 were considered as positive for fibrosis. Sensitivity, specificity, positive and negative predictive values and accuracy were calculated in the case of absence, positivity of one or all the US parameters. The correlation between US and histological scores was evaluated with Spearman's test.


RESULTS
At histology seventy-seven patients (73%) had absent grade 0 (1 patient; 1%), low-moderate grade 1 (35 patients; 33%) or grade 2 (41 patients; 39%) liver fibrosis. Twenty-eight patients (27%) had severe grade 3 (16 patients; 15%) or grade 4 (12 patients; 11%) fibrosis. In the case of absence of US parameters sensitivity was 32%, specificity 32%, positive predictive value 15%, negative predictive value 57% and accuracy 32%. In the case of positivity of at least one of the US parameters the values were 68%, 68%, 43%, 84% and 69%. In the case of presence of all the US signs the results were 25%, 100%, 100%, 79% and 80%. None of the 77 patients with a healthy liver or with low-grade fibrosis was positive for all the US parameters. All the patients positive for all of the ultrasonographic parameters had high-grade fibrosis or cirrhosis at liver biopsy. Correlation between B-mode and histological scores was not statistically significant (Rs=0.45; p=0.0001).


CONCLUSIONS
US identification of liver fibrosis in chronic liver disease is possible with 25% sensitivity, 100% specificity, 100% positive predictive value and 79% negative predictive value, with an 80% diagnostic accuracy.
D'Onofrio
Mirko
M
Istituto di Radiologia, Policlinico Universitario G. B. Rossi, Verona, Italy. mirko.donofrio@univr.it
Martone
Enrico
E
Brunelli
Silvia
S
Faccioli
Niccolò
N
Zamboni
Giulia
G
Zagni
Irene
I
Fattovich
Giovanna
G
Pozzi Mucelli
Roberto
R
D001707:Biopsy, Needle; D005260:Female; D006521:Hepatitis, Chronic / Q000150:complications*; D006525:Hepatitis, Viral, Human / Q000150:complications*; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging* / Q000473:pathology / Q000821:virology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional