Surgery of the Parotid Gland

Richard L. Fabian

Parotidectomy for tumor resection has evolved from simple tumor enucleation with lifelong recurrences to formal en bloc gland excision with preservation of the facial nerve when possible. The formality of facial nerve identification, near total gland excision for benign tumors, and the refinement of nerve repair techniques when malignant disease does not allow nerve preservation continue to be the surgical standard for resident training and practice.

• Benign tumors of the parotid gland constitute nearly 95% of all parotid neoplasms in adults. Benign tumors are usually mobile, often less than 3 cm, and located in the body, tail, or posterior margin of the superficial lobe. It is also common to encounter one or more branches of the facial nerve intimately associated and stretched over the benign tumor, eliminating the possibility of wide surgical margins. There are also encounters where a high probability of lymphoproliferative or inflammatory disease does not justify an extensive procedure.
  
• Tumor recurrence, especially of benign disease, is related to tumor breech and surgical spill and not to close margin dissection.

• Interaction with anesthesia is important before and after induction occurs. Endotracheal tube position should be maintained with tape fixation of the tube away from the operative side. Eye protection with tape on the contralateral side is acceptable. Eye protection on the operative side is achieved with a corneal shield.
  
• No paralytic agents are used if nerve stimulation is to be performed. This request must be voiced for each case and not assumed by the surgeon.
  
• To minimize bleeding, anesthesia is requested to keep the systolic blood pressure as low as the patient’s medical condition and risk status permit. Inadequate blood pressure control justifies case cancellation rather than suffering through constant bleeding and potential nerve injury.
  
• A preoperative instrument check should include a facial nerve simulator with variable stimulus control, a Bovie unit, a bipolar coagulator, and fine-tipped mosquito and tonsil clamps.
  
• Useful retractors include an intermediate-size periorbital retractor, a midsize Richardson retractor, and a pair of Army/Navy retractors.
  
• To facilitate parotid exposure, shoulder elevation and head extension on a thyroid bag are common. It is essential to determine preoperatively whether the patient has a history of cervical spine or disk disease. If so, thyroid bag extension is contraindicated.