Person:

Hadlock, Tessa

Objectives: Vestibular schwannomas are the hallmark of neurofibromatosis 2 (NF2), occurring in >95% of patients. These tumors develop on the vestibulocochlear nerve and are associated with significant morbidity due to hearing loss, tinnitus, imbalance, facial weakness, and risk of early mortality from brainstem compression. Although hearing loss and facial weakness have been identified as important functional outcomes for patients with NF2, there is a lack of consensus regarding appropriate endpoints in clinical trials.

Methods: The functional outcomes group reviewed existing endpoints for hearing and facial function and developed consensus recommendations for response evaluation in NF2 clinical trials.

Results: For hearing endpoints, the functional group endorsed the use of maximum word recognition score as a primary endpoint, with the 95% critical difference as primary hearing outcomes. The group recommended use of the scaled measurement of improvement in lip excursion (SMILE) system for studies of facial function.

Conclusions: These recommendations are intended to provide researchers with a common set of endpoints for use in clinical trials of patients with NF2. The use of common endpoints should improve the quality of clinical trials and foster comparison among studies for hearing loss and facial weakness.

Peripheral nerve injury is a common clinical entity, which may arise due to traumatic, tumorous, or even iatrogenic injury in craniomaxillofacial surgery. Despite advances in biomaterials and techniques over the past several decades, reconstruction of nerve gaps remains a challenge. Autografts are the gold standard for nerve reconstruction. Using autografts, there is donor site morbidity, subsequent sensory deficit, and potential for neuroma development and infection. Moreover, the need for a second surgical site and limited availability of donor nerves remain a challenge. Thus, increasing efforts have been directed to develop artificial nerve guidance conduits (ANCs) as new methods to replace autografts in the future. Various synthetic conduit materials have been tested in vitro and in vivo, and several first- and second-generation conduits are FDA approved and available for purchase, while third-generation conduits still remain in experimental stages. This paper reviews the current treatment options, summarizes the published literature, and assesses future prospects for the repair of peripheral nerve injury in craniomaxillofacial surgery with a particular focus on facial nerve regeneration.