With any such surgery, risks include cranial nerve damage, leakage of cerebrospinal fluid, and infection.29,32 Postsurgically, about half of patients report frequent headaches, which are persistent in about half of these cases.36-38 Another concern is preservation of the facial nerves, with a risk for temporary facial weakness or dysfunction.3,24,39 Less than 2% of patients who undergo microsurgery require additional treatment.29
Stereotactic radiosurgery. These procedures, which are performed using the Gamma Knife,® the CyberKnife, or the linear accelerator,29,40,41 are considered appropriate for patients with smaller tumors and those who are not candidates for conventional surgery.1 Trigeminal neuropathy, injury to the facial nerves, and hydrocephaly are reported complications of Gamma Knife radiosurgery, but improvements in these technologies are ongoing.1,2,40
Patient Outcomes
The outcome in a patient with vestibular schwannoma depends on the treatment administered, but prolonged follow-up is typically necessary. For patients being managed through observation, annual brain scans are recommended for 10 years, with subsequent scans every three to five years if no tumor growth is seen. For patients who have had surgery, annual brain scans are advised for the successive eight to 10 years, with decreasing frequency if no tumor remains. In patients who undergo radiation, annual scans are recommended for 10 years, then every two years if no tumor growth is detected.36
Psychosocial experiences vary widely among patients who have undergone treatment for vestibular schwannomas. Some are unable to perform necessary or recreational activities, and others must retire early from work.42 Others, however, have minimal disruption in their lives and enjoy a good quality of life. The most difficult consequence of vestibular schwannoma and its treatment, according to patients, is the associated hearing loss.8,19
THE CASE PATIENT
The 22-year-old patient in this case had an atypical presentation of vestibular schwannoma. Although she did present with vertigo, she also complained of headache, nausea, and photophobia—which are rarely reported in investigations of these tumors. She was also younger than the typical patient and did not report tinnitus.
The case patient reportedly underwent surgery and subsequent radiation to treat the remaining portion of her tumor. She suspended her attendance at the college and, as of this writing, has not re-enrolled. She was lost to follow-up.
CONCLUSION
For the primary care provider, diagnostic challenges require great clinical acumen. Vertigo, headache, hearing loss, and tinnitus are all symptoms seen in the primary care setting; when they occur together, the clinician should be alerted to investigate further. A high level of suspicion is appropriate when a patient complains of longstanding auditory symptoms, with or without headache. Unilateral hearing loss is a common symptom in patients with vestibular schwannomas, although some may present with facial weakness or pain, imbalance, and/or vertigo.
In addition to the history and physical exam, experts recommend that audiometry and MRI be considered, particularly if hearing loss is unilateral. Genetic screening for NF2 should be performed if vestibular schwannoma is found on MRI. Referral to a neurologist, a neurosurgeon, or an otolaryngologist is appropriate.
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