A fifty year old male patient was diagnosed with a malignant tumor of the right parotid gland necessitating surgical removal. During the operative procedure, the surgeon noted the tumor extended to the deep lobe of the gland and therefore removed the entire gland. The patient recovered from the surgery and received postoperative radiation therapy to eliminate possible metastases that might have occurred.

Immediately after surgery the following symptoms were observed on the ipsilateral side of the face:

• The mouth was displaced as a result of unopposed contraction of the muscles on the uninjured side
• The wrinkles on the right side of the face were smoother and less pronounced.
• He had ptosis (drooping) of the upper right eyelid and the lower right eyelid was slightly everted. He could not close or blink the right eye.

As a result he developed conjunctivitis and eventually corneal scarring which led to blindness in the right eye. Further testing revealed there was no decreased lacrimation and no loss of taste sensation from the anterior two-thirds of the tongue. Although blind in the right eye, the patient was free from cancer and pronounced cured.

QUESTIONS

1. What muscles appear to be non-functional?
2. What structure was probably cut during the surgery?
3. Describe the relationship of this structure to the parotid gland.
4. Why was there severe muscle loss, but no impairment of lacrimation or taste?
5. What might be some other ways that this condition could be brought about?