Intraoperative deformation during laryngoscopy of irradiated and non-irradiated patients

摘要

In trans-oral surgeries, large intraoperative deformations limit the surgeons' use of preoperative images to accurately resect tumors while traditional metal instruments render intraoperative images ineffective. A CT/MR compatible laryngoscopy system was developed previously to allow for the study of these deformations with intraoperative imaging. For this study, we compare the deformation analysis of two patient groups: those who had received prior radiation to the upper aerodigestive tract (irradiated) and those who have not (non-irradiated). We speculate that differences in tissue deformation exist between these two groups due to radiation-induced fibrosis (RIF) and that quantifying these distinct deformation patterns will lead to more patient-specific tissue modeling. Thirteen patients undergoing diagnostic laryngoscopy were recruited: five had been irradiated and eight had not. Artifact-free images were obtained and registered. Mandible, hyoid, and tongue region displacements were quantified. For the bony structures, significant differences were observed in certain displacement directions as well as magnitude, with the irradiated patient group experiencing less anatomical shift (non-irradiated vs irradiated: (Mandible) 12.6±3.6mm vs 7.9±2.8mm, p=0.029; (Hyoid) 13.3±3.1mm vs 9.0± 1.8mm, p=0.019). For the tongue, average displacements of tongue fiducials were 26.2±11.1mm vs 22.9±8.4mm respectively (p=0.033). The data from this study can serve as ground truth to generate and evaluate upper aerodigestive tract deformation models to predict the intraoperative state and provide guidance to the surgeons.