A Fully Automated Procedure for the Creation of Digital Patient-Specific Surgical Guides for Ear Reconstruction

Autologous ear reconstruction is a surgical procedure aimed at total or partial reconstruction of the ear of patients with microtia, which is a malformation or absence of the anatomical element. This procedure involves harvesting cartilage material from the patient at the costal level, cut and sculpt the tissue to create the skeleton of the ear, which is then inserted into a subcutaneous pocket in the malformed region. The sculping procedure takes inspiration from the geometry of the patient’s contralateral healthy ear and can be very complex given the particularity of the elements to be reconstructed. Taking advantage of Reverse Engineering and Additive Manufacturing technologies, the authors, in collaboration with hospital staff, proposed patient-specific three-dimensional cutting guides that can facilitate the surgeon in sculpting the ear structure. In this work, a fully automated procedure for creating the printable digital model of such guides is proposed: at first is performed the segmentation of ear elements, which represent the starting data for the automated CAD modelling of the surgical guides. The automatic CAD modelling procedure was tested and validated by medical personnel.