A novel in vivo approach to assess strains of the human abdominal wall under known intraabdominal pressure

TL;DR

This paper introduces a non-invasive in vivo optical method to measure strains in the human abdominal wall under known intraabdominal pressure, aiding in understanding its mechanical properties for better surgical mesh design.

Contribution

It presents a novel optical measurement technique during standard dialysis procedures to assess abdominal wall strains and deformation states in living humans.

Findings

Measured principal strains from -10% to 17%.

Intraabdominal pressure ranged from 11 to 18.5 cmH₂O.

Method enables deformation analysis under physiological loading.

Abstract

The study concerns mechanical behaviour of a living human abdominal wall. A better mechanical understanding of a human abdominal wall and recognition of its material properties is required to find mechanically compatible surgical meshes to significantly improve the treatment of ventral hernias. A non-invasive methodology, based on in vivo optical measurements is proposed to determine strains of abdominal wall corresponding to a known intraabdominal pressure. The measurement is performed in the course of a standard procedure of peritoneal dialysis. A dedicated experimental stand is designed for the experiment. The photogrammetric technique is employed to recover the three-dimensional surface geometry of the anterior abdominal wall at the initial and terminal instants of the dialysis. This corresponds to two deformation states, before and after filling the abdominal cavity with dialysis fluid. The study provides information on strain fields of living human abdominal wall. The inquiry is aimed at principal strains and their directions, observed at the level from -10% to 17%. The intraabdominal pressure related to the amount of introduced dialysis fluid measured within the medical procedure covers the range 11-18.5 cmH$_2$O. The methodology leads to the deformation state of the abdominal wall according to the corresponding loading conditions. Therefore, the study is a step towards an identification of mechanical properties of living human abdominal wall.