2025 Poster Presentations
P100: PETROUS CAROTID CANAL SYMPATHETIC PLEXUS SCHWANNOMA: A CASE REPORT AND LITERATURE REVIEW
Braeden Lovett, MD; Matthew Koch, MD; Nohra Chaluli; Rex Haberman, MD; Si Chen, MD; University of Florida
Forty-year-old female presented with progressive left-sided conductive hearing loss and aural fullness for 10 years. Physical exam showed a blue bulging mass within the left mesotympanum. She had several myringotomy tubes placed prior to presentation at a tertiary care center. Audiogram showed purely conductive hearing loss. CT imaging demonstrated left middle ear and mastoid opacification, as well as a petrous apex lesion with bony erosion of the petrous carotid canal and focal dehiscence of the apical turn of the cochlea. MRI revealed a large, homogenous, enhancing mass surrounding the left petrous carotid artery extending from the foramen lacerum to cavernous sinus with protrusion into the epitympanum. MR angiogram was concerning for carotid artery aneurysm. Diagnostic angiography revealed slight narrowing of the left petrous carotid by tumor but no pseudoaneurysm or aneurysm. Differential diagnosis for petrous apex lesion includes mucocele, cholesterol granuloma, schwannoma, meningioma, rhabdosarcoma, and metastasis. The signal intensity and enhancement characteristics of the mass are consistent with a very unusual spread of a nerve sheath tumor along the sympathetic plexus of the internal carotid artery through the skull base. Petrous carotid sympathetic chain (PCSC) schwannomas are rarely described with only 6 other cases documented in the literature. Tinnitus, aural fullness, and hearing loss were common presenting symptoms in most cases. Four out of 6 cases underwent gross total resection via an extradural middle fossa approach. While this disease entity is seemingly rare, it is an important one to include among the other differential diagnoses for a petrous apex mass.
