Eagle Syndrome, A Third Variant: Giant Styloid Processes, Pseudoarthrosis, and Unilateral Facial Spasms Progressing to Facial Paralysis

We describe a third variant of Eagle syndrome characterized by (1) neck pain (2) giant, hypertrophied styloid processes, (3) mobile styloid process due to pseudoarthrosis, and (4) combined facial nerve compression/entrapment leading to facial spasms and paralysis. Our patient presented with symptoms of Eagle syndrome, bilateral giant styloid processes, and left facial spasms progressing to left facial paresis/paralysis. CT findings included a pseudoarthrosis of the base of a giant left styloid process and overgrowth of bone superior to the styloid base. The mobile styloid process resulted in compression of the facial nerve exiting the stylomastoid foramen and facial spasms with head rotation to the left. Bony overgrowth superior to the pseudoarthrosis led to stenosis of the facial canal distal mastoid segment. Along with compression from the styloid, nerve entrapment contributed to facial paresis that progressed to facial paralysis. Left styloidectomy was performed to alleviate impingement on the facial nerve, and left canal wall-up tympanomastoidectomy with facial nerve decompression was performed to alleviate entrapment caused by bony overgrowth. Two months postoperatively, the patient's left facial paralysis improved to mild left eyelid lag without signs or symptoms of ocular exposure. The patient developed delayed first-bite syndrome successfully treated with amitriptyline. She did not report postoperative dysgeusia. Our patient's left facial paresis was initially attributed to viral neuritis, and the possibility of Eagle syndrome was not initially considered. The relative rarity and varied presentations of Eagle syndrome often create a diagnostic challenge, especially for patients with progressive symptoms. Our patient's presentation emphasizes the importance of a thorough head and neck evaluation of any patient presenting with head and neck signs or symptoms persisting for longer than 3 weeks as well as awareness of what we believe is the first description of a third variant of Eagle syndrome.