Application of computer tomography-based 3D reconstruction technique in hernia repair surgery

Polyurethane-based three-dimensional printing for biological mesh carriers

Repair and reconstruction of the myopectineal orifice area using meshes is the mainstay of surgical treatment of inguinal hernias. However, the limitations of existing meshes are becoming increasingly evident in clinical applications; thus, the idea of using three-dimensionally (3D)-printed biological meshes was put forward. According to the current level of the 3D printing technology and the inherent characteristics of biological materials, the direct use of the 3D printing technology for making biological materials into finished products suitable for clinical applications is not yet supported, but synthetic materials can be first printed into 3D form carriers, compounded with biological materials, and finally made into finished products. The purpose of this study was to develop a technical protocol for making 3D-printed biomesh carriers using polyurethane as a raw material. In our study: raw material, polyurethane; weight, 20-30 g/m2; weaving method, hexagonal mesh; elastic tension aspect ratio, 2:1; diameters of pores, 0.1-1 mm; surface area, 8 × 12 cm2; the optimal printing layer height, temperature and velocity were 0.1 mm, 210-220 °C and 60 mm/s. Its clinical significance lies in: (1) applied to preoperative planning and design a detailed surgical plan; (2) applied to special types of surgery including patients in puberty, recurrent and compound inguinal hernias; (3) significantly improve the efficiency of doctor-patient communication; (4) it can shorten the operation and recovery period by about 1/3 and can save about 1/4 of the cost for patients; (5) the learning curve is significantly shortened, which is conducive to the cultivation of reserve talents.

Development and Implantation of 3D Anatomically Tailored Polypropylene Mesh for Laparoscopic Inguinal Hernia Repair Designed on the Basis of CT Images (the ILAM Study)

OBJECTIVE

The aim of the ILAM (Individualized Laparoscopic Anatomical Mesh) study was to create and implant a fully individualized mesh based on CT scans, taking into account the published body of knowledge about the material and mechanical behavior of the implant for laparoscopic inguinal hernia repair.

SUMMARY BACKGROUND DATA

The team creating and conducting this study consisted of surgeons and engineers. A specific project was made and divided into 4 phases.

METHODS

The process of development and implantation was divided into 4 milestones: CT scans and modeling based on predefined subgroups, mesh manufacture, certification and clinical evaluation.

RESULTS

The result of the study was the first individually designed hernia mesh to have been implanted in a human subject. After 12 months of follow-up, no recurrences or other complications were reported.

CONCLUSIONS

The new mesh provides a better anatomic fit to the patients' inguinal region geometry. Mechanical stability is ensured by the multiple contact points between the implant and the tissues, which generate friction forces. Together with the possibility of shape design (proper overlap), the authors believe that there is no need for mesh fixation. If so, the use of such design meshes can change the guidelines in laparoendoscopic hernia repair in the future.

The Myopectineal Orifice: A Study of Thai Cadavers

Objective

This study aimed to determine the myopectineal orifice size measured in Thai human cadavers.

Materials and Methods

A total of 30 human cadavers, comprising 55 groins, were assessed. Myopectineal orifices (MPOs) were measured in two dimensions: height from the lower border of the conjoined tendon to the upper border of the pectineal ligament and width from the lateral border of pubic tubercle to the medial border of the iliopsoas muscle.

Results

The mean MPO size is 7.13 + 0.14 cm in width and 6.66 + 0.32 m in height. The mean width and height in male cadavers are 7.16 + 0.14 and 6.84 + 0.27 cm, respectively. The mean width and height in female cadavers are 7.09 + 0.12 and 6.45 + 0.24 cm, respectively. The mean MPO area is 37.26 ± 0.027 cm², compared with the area of mesh graft 10 cm × 15 cm, 150 cm². Although the shrinkage of cadaveric tissue and mesh size were adjusted, which were 39.56 ± 0.029 and 81 cm², respectively, they were found to be sufficient for the mean MPO area. It was found that the mesh size was sufficient for the mean MPO area.

Conclusion

A mesh size of 10 cm × 15 cm is found to be the appropriate size to cover the MPO among Thais.