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
REFERENCES
-
1
Griffiths T D, Bates D, Rees A, Witton C, Gholkar A, Green G G.
Sound movement detection deficit due to a brainstem lesion.
J Neurol Neurosurg Psychiatry.
1997;
62
522-526
-
2
Meyer B, Kral T, Zentner J.
Pure word deafness after resection of a tectal plate glioma with preservation of wave V of brain stem auditory evoked potentials.
J Neurol Neurosurg Psychiatry.
1996;
61
423-424
-
3
Masuda S, Takeuchi K, Tsuruoka H, Ukai K, Sakakura Y.
Word deafness after resection of a pineal body tumor in the presence of normal wave latencies of the auditory brain stem response.
Ann Otol Rhinol Laryngol.
2000;
109
1107-1112
-
4 Webster D B, Popper A N, Fay R R. The Mammalian Auditory Pathway: Neuroanatomy. New York; Springer-Verlag 1992: 66-116
-
5
Brackmann D E, Owens R M, Friedman R A et al..
Prognostic factors for hearing preservation in vestibular schwannoma surgery.
Am J Otol.
2000;
21
417-424
-
6
Stidham K R, Roberson Jr J B.
Hearing improvement after middle fossa resection of vestibular schwannoma.
Otol Neurotol.
2001;
22
917-921
-
7
Inoue Y, Ogawa K, Kanzaki J.
Hearing improvement after tumor removal in a vestibular schwannoma patient with severe hearing loss.
Eur Arch Otorhinolaryngol.
2003;
260
487-489
-
8
Rohit , Piccirillo E, Jain Y, Augurio A, Sanna M.
Preoperative predictive factors for hearing preservation in vestibular schwannoma surgery.
Ann Otol Rhinol Laryngol.
2006;
115
41-46
-
9
Ferber-Viart C, Colleaux B, Laoust L, Dubreuil C, Duclaux R.
Is the presence of transient evoked otoacoustic emissions in ears with acoustic neuroma significant?.
Laryngoscope.
1998;
108
605-609
-
10
Qiu W W, Stucker F J, Nguyen H H, Yin S S.
Effects of brain stem lesions on cochlear function: mechanism of hearing improvement after removal of a brain stem tumor.
Otolaryngol Head Neck Surg.
1996;
115
560-567
Kris A SmithM.D.
c/o Neuroscience Publications, Barrow Neurological Institute
350 W. Thomas Road, Phoenix, AZ 85013
Email: neuropub@chw.edu
