Usefulness of textural analysis as a tool for noninvasive liver fibrosis staging.
OBJECTIVE
Noninvasive diagnosis of liver fibrosis is a popular topic in the medical literature. Textural analysis on B-mode ultrasound is viewed as a noninvasive tool for fibrosis staging. A liver tissue model is proposed and used to simulate ultrasound images.


METHODS
One hundred and twenty-five patients with chronic hepatitis C were included in this study. Patients were investigated using B-mode ultrasound and liver biopsy (Metavir scoring). A texture analysis tool consisting of 12 algorithms and a logistic regression classifier was implemented and validated. Tissue model parameters were varied and ultrasound images were generated.


RESULTS
Texture analysis can discriminate between stages F0 and F4 using actual patient data (accuracy 69.5%) and synthetic images (accuracy 76.6%). A human expert is less sensitive than texture analysis in discriminating subtle changes in ultrasound images. High fibrosis detection accuracies are correlated with larger differences in portal space density (r (2) = 0.5). Accuracies measured when we varied only the fibrosis stage and kept the rest of the tissue parameters constant showed high detection rates only in a narrow parameter interval.


CONCLUSIONS
The texture analysis system shows limited performance in staging fibrosis and it cannot be used for accurate monitoring of fibrosis evolution over time.
Automation and Computer Science, Technical University of Cluj-Napoca, Memorandumului Str. No. 28, 400114, Cluj-Napoca, Romania. cristian.vicas@cs.utcluj.ro.
Cristian
C
Vicas
Department of Ultrasonography, 3rd Medical Clinic, 19-21 Croitorilor St., Cluj-Napoca, Romania.
Monica
M
Lupsor
Department of Ultrasonography, 3rd Medical Clinic, 19-21 Croitorilor St., Cluj-Napoca, Romania.
Radu
R
Badea
Automation and Computer Science, Technical University of Cluj-Napoca, Memorandumului Str. No. 28, 400114, Cluj-Napoca, Romania.
Sergiu
S
Nedevschi
Fibrosis staging; Noninvasive diagnosis; Texture analysis; Tissue model