Measurement of the mechanical properties of the human gallbladder

Abstract

Gallbladder is a small organ of the body which is located in the right side of the liver. It is responsible of storing the bile and releasing it to the intestine. The gallbladder can subject to the mechanical deformation/loading as a result of the cholecystitis, cholesterolosis of the gallbladder, etc. However, so far the mechanical properties of the human gallbladder have not been measured. This study was aimed at conducting an experimental study to measure the mechanical properties of the human gallbladder under the axial and transversal tensile loadings. To do that, the gallbladder tissue of 16 male individuals was excised during the autopsy and subjected to a series of axial and transversal loadings under the strain rate of 5 mm/min. The amount of elastic modulus as well as the maximum/failure stress of the tissues were calculated via the resulted stress–strain diagrams and reported. The results revealed that the axial and transversal elastic modulus were 641.20 ± 28.12 (mean ± SD) and 255 ± 24.55 kPa, respectively. The amount of maximum stresses was also 1240 ± 99.94 and 348 ± 66.75 kPa under the axial and transversal loadings, respectively. The results revealed a significantly higher axial stiffness (p < .05, post hoc Scheffe method) compared to the transversal one. These findings have implications not only for understanding the axial and transversal mechanical properties of the human gallbladder tissue, but also for providing a diagnosis tool for the doctors to have a suitable threshold value of the healthy gallbladder tissue.

Keywords:

• Gallbladder
• axial and transversal loadings
• mechanical properties
• elastic modulus

Acknowledgement

Thanks to the Basir Eye Health Research Center.

Ethical issues

The use of experimental on the human body was approved by the committee of the Iranian Legal Medicine Organisation (LMO) with the letter ID of 65987/253. This study was also entirely adhered to the declaration of the Helsinki in 2008 and committee approval of Baghyatallah University of Medical Sciences, Baghyatallah Hospital, Tehran, Iran. The experimental study was entirely carried out in Iran under the above permissions. Since the first author, namely Alireza Karimi, now works under the affiliation of Kyushu University, the mentioned affiliation was assigned to this author. All rights and responsibilities of the experimental human studies are under the supervision of Iranian Legal Medicine Organisation.

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.