Frontoethmoidal Schwannoma with Exertional Cerebrospinal Fluid Rhinorrhea: Case Report and Review of Literature.

BACKGROUND: Frontoethmoidal schwannomas are rare. No case manifesting exertional cerebrospinal fluid (CSF) rhinorrhea has ever been reported to the best of our knowledge.

CASE DESCRIPTION: In this report, we describe an extremely rare case of frontoethmoidal schwannoma extending through the olfactory groove with exertional CSF rhinorrhea as the initial symptom. A 50-year-old woman was presented to our clinic for frequent nasal discharge on exertion. A postcontrast computed tomographic scan demonstrated heterogeneously enhanced tumor from the anterior cranial fossa to the anterior ethmoid sinus. A gadolinium-enhanced T1-weighted magnetic resonance image revealed a well-defined heterogeneously enhanced tumor situated in the midline anterior cranial fossa and anterior ethmoid sinus. After the resection, the defect of the right anterior skull base was reconstructed with a fascia graft and adipose tissue taken from the abdomen, as well as a pedicle periosteum flap. A histologic examination revealed the tumor as schwannoma. Her rhinorrhea completely resolved. She regained her sense of smell and taste 1 month after the operation.

CONCLUSION: According to previous reports, olfactory groove, and paraolfactory groove/periolfactory groove schwannomas can be divided into 4 types: subfrontal, nasoethmoidal, frontoethmoidal, and ethmofrontal. Among them, a frontoethmoidal schwannoma can manifest exertional CSF rhinorrhea as an initial symptom.