The Role of Anatomical Location of Parotid Tumors in the Incidence of Post-Operative Facial Nerve Paresis

Objective: The parotid part of the Facial nerve dividing the parotid gland into the superficial and deep lobe. This close relation of the facial nerve to the parotid gland making the facial nerve at high risk of injury during parotid gland surgery. The current study aimed to evaluate the diagnostic accuracy of CT for evaluation of the anatomical location of parotid tumors and its relation to the incidence of post-operative facial nerve paresis with antegrade dissection technique. Methods: The study enrolled the patients undergoing surgical removal of parotid tumors. Preoperative evaluation of the tumor location within the parotid gland tumor was done using axial and coronal CT. The primary outcome factor was the tumor location within the parotid gland. While secondary outcome factors were patient age, tumor size. Results: Deep lobes, upper and anterior part tumors are associated with higher incidence of the TFND (P < 0.001, <0.0001, <0.0349, respectively). While, tumors located in the lower parts, posterior parts or the superficial lobe are showing lower incidence of TFND. With respect to tumor size, there was no significant association between the tumor size and incidence of facial nerve injury. The other clinical factors (age & sex) did not show a relation to the incidence of the TFND. Conclusion: The tumor location is the most significance factor of postoperative TFND. The incidence of TFND is highly significant with tumors located in the upper parts, and/or anterior parts and/or deep lobe of the parotid gland.