A preliminary study of the local biomechanical environment of liver tumors in vivo.
PURPOSE
Biomechanical properties can be used as biomarkers to diagnose tumors, monitor tumor development, and evaluate treatment efficacy. The purpose of this preliminary study is to characterize the biomechanical environment of two typical liver tumors, hemangiomas (HEMs) and hepatocellular carcinomas (HCCs), and to investigate the potential of using strain metrics as biomarkers for tumor diagnosis, based on a limited clinical dataset.


METHODS
Magnetic resonance (MR) tagging was used to quantify the motion and deformation of the two types of liver tumors. Displacements of the tumors arising from a heartbeat were measured over one cardiac cycle. Local biomechanical conditions of the tumors were characterized by estimating two principal strains (ε1 and ε2 ) and an octahedral shear strain (εsoct ) of the tumor and its peripheral region. Biomechanical conditions of the tumors were compared with those of the arbitrarily selected regions from healthy volunteers.


RESULTS
We observed that the HCCs had significantly smaller strain values compared to their peripheral tissues. However, the HEMs did not have significantly different strains from those of the peripheral tissues, and were similar to healthy liver regions. The sensitivity of using ε1 , ε2 , and εsoct to diagnose HCC were all 1, while the sensitivity of using ε1 , ε2 , and εsoct to diagnose HEM were 0.67, 0.17, and 0.67, respectively.


CONCLUSIONS
Lagrangian strain metrics provide insight into the biomechanical conditions of certain liver tumors in the human body and may provide another perspective for tumor characterization and diagnosis.
['Ma|Shengyuan|S|', 'Zhu|Mo|M|', 'Xia|Xiaolong|X|', 'Guo|Liang|L|', 'Genin|Guy M|GM|', 'Sacks|Michael S|MS|', 'Gao|Mingyuan|M|', 'Mutic|Sasa|S|', 'Hu|Yanle|Y|', 'Hu|Chun-Hong|CH|', 'Feng|Yuan|Y|']
D000328:Adult D000368:Aged D006528:Carcinoma, Hepatocellular D003287:Contrast Media D005260:Female D006391:Hemangioma D006801:Humans D007091:Image Processing, Computer-Assisted D008113:Liver Neoplasms D008279:Magnetic Resonance Imaging D008297:Male D008875:Middle Aged D055815:Young Adult
biomechanics displacement Lagrangian strain MR tagging liver cancer