ABSTRACT
Although hearing improvement after surgery for small tumors of the cerebellopontine
angle has been reported, the mechanism by which surgery leads to the improvement in
hearing remains controversial. We report a patient who sought treatment for progressive
tinnitus and hearing loss. Magnetic resonance imaging showed a large (5-cm) schwannoma
in the cerebellopontine angle. At surgery the lesion was found to originate from rootlets
of cranial nerve X at the jugular foramen. The patient underwent gross total resection
of the tumor. Immediately after surgery, his hearing improved dramatically. We believe
that our patient represents an example of hearing impairment at least in part referable
to direct compression of the brainstem. Importantly, the patient's hearing deficit
was completely reversible. Some authors claim that surgery to preserve hearing may
be contraindicated in patients with speech discrimination scores below 50%. However,
when extrinsic brainstem compression may contribute to the cause of such a hearing
decrement, postoperative improvement in hearing may be a reasonable expectation.
KEYWORDS
Jugular foramen schwannoma - hearing - retrosigmoid craniotomy - cerebellopontine
angle
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Kris A SmithM.D.
c/o Neuroscience Publications, Barrow Neurological Institute
350 W. Thomas Road, Phoenix, AZ 85013
Email: neuropub@chw.edu
