Robust computational osteotomy planning tools for autologous bone grafts in reconstructive surgery

摘要

This paper presents a method for computer assisted selection of optimal donor sites for autologous osseous grafts in the craniofacial surgery. At the initial graft design stage the surgeon defines in the CT data set the shape of the bone segment to be reconstructed and in the donor region CT data set a set of constraints for the optimization task. This non-automatic step is followed by a fully automatic optimization stage, which delivers a set of sub-optimal and optimal donor sites for a given template. Such approach permits the surgeon to find the best site for harvesting the graft and enables an exact anatomical reconstruction of the osseous section. Bone graft surgery is often necessary for reconstruction of craniofacial defects after trauma, tumor, infection or congenital malformation. Since F.H. Albee published in 1915 an influential text on bone graft surgery[l], the bone grafting has became more widespread and attention focused not only on its use, but also on its safety and efficacy, hi this operative technique the removed or missing bone segment is filled with bone graft. The mainstay of the craniofacial reconstruction rests with the replacement of the defected bone by autologous bone grafts. There are a number of alternatives to autologous grafts but the autogenous bone is still the best source of bone grafts because it offers the complete histocompatibility and provides the best osteoinductive and osteoconductive stimuli for bone growth. Grafting techniques have markedly changed over the last decades in an attempt to provide better correction of the bone defects, enhance stabilization, and increase the rate of bony consolidation. To achieve sufficient incorporation of the autograft into the host bone, precise planning and simulation of the surgical intervention is required.