Introduction: Acoustic neuromas in patients with neurofibromatosis type 2 (NF2) may be associated with a higher operative risk than sporadic tumors. We sought to investigate the association of NF2 and acoustic neuroma resection outcome across the American population.
Methods: Data were extracted from the Nationwide Inpatient Sample (2002-2011). Patients with a primary procedure code of an acoustic neuroma resection were included and stratified based on the presence of NF2. Multivariate logistic regression evaluated the association of NF2 with facial nerve dysfunction, hearing loss, in-hospital mortality, neurologic complications, non-neurological medical complications, and length of stay. Covariates included in all analyses were patient age, sex, admission year, admission type, comorbidities, expected primary payer, concomitant hydrocephalus, cerebral edema, and prior stereotactic radiosurgery.
Results: 4,477 admissions were analyzed, of whom 2.6% (n=117) had a diagnosis of NF2. Patients with NF2 were significantly younger, had fewer comorbidities, and higher rates of hydrocephalus compared to those without neurofibromatosis (P=0.04). Patients with NF2 were associated with increased odds of facial nerve dysfunction (29.9% versus 15.0%, OR: 1.80, 95% CI: 1.08-3.01, P=0.03) and hearing loss (41.0% versus 26.3%, Odds Ratio (OR): 2.32, 95% Confidence Interval (CI): 1.52-3.57, P<0.001) compared to those without NF, although the NIS does not specify if cranial nerve dysfunction was present pre-operatively or if bilateral tumors were present. Neither in-hospital mortality nor neurological complications were found to be associated with a diagnosis of NF2. However, those with NF2 had higher odds of developing a medical (non-neurologic) complication (33.3% versus 15.7%, OR: 2.65, 95% CI: 1.58-4.46, P<0.001) and having a length of stay of at least 6 days (OR: 1.85, 95% CI 1.23-2.79, P=0.003).
Conclusions: In this nationwide analysis, NF2 patients undergoing acoustic neuroma resection harbored higher rates of facial nerve dysfunction, hearing loss, medical non-neurologic complications, and had longer hospital stay, compared to sporadic cases.
Patient Care: We highlight the increased risks associated with neurofibromatosis-associated acoustic neuroma resection and the need for careful consideration of the management strategies and operative indications in this population.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the risks associated with resection of sporadic and neurofibromatosis-associated acoustic neuromas; 2) Compare the risks of surgery in NF2 patients compared to the general population.