Chondromyxoid fibroma of the mastoid facial nerve canal mimicking a facial nerve schwannoma.
Chondromyxoid fibroma of the skull base is a rare entity. Involvement of the temporal bone is particularly rare. We present an unusual case of progressive facial nerve paralysis with imaging and clinical findings most suggestive of a facial nerve schwannoma. The lesion was tubular in appearance, expanded the mastoid facial nerve canal, protruded out of the stylomastoid foramen, and enhanced homogeneously. The only unusual imaging feature was minor calcification within the tumor. Surgery revealed an irregular, cystic lesion. Pathology diagnosed a chondromyxoid fibroma involving the mastoid portion of the facial nerve canal, destroying the facial nerve.
Thompson
Andrew L
AL
Division of Neuroradiology, Department of Medical Imaging, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
Bharatha
Aditya
A
Aviv
Richard I
RI
Nedzelski
Julian
J
Chen
Joseph
J
Bilbao
Juan M
JM
Wong
John
J
Saad
Reda
R
Symons
Sean P
SP
D000328:Adult; D002812:Chondroma / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D003937:Diagnosis, Differential; D005154:Facial Nerve / Q000473:pathology*; D005260:Female; D005350:Fibroma / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008416:Mastoid / Q000294:innervation* / Q000601:surgery; D009442:Neurilemmoma / Q000175:diagnosis; D014057:Tomography, X-Ray Computed