Case Presentation Conference-Memorial-

January 24, 2002Jason Hunt M.D.

Brian Kerr M.D.

Peter Rigby M.D.

Chief Complaint

• 65 y.o. female presents with complaint of decreased hearing in the left ear.

• Has worsened over several years

• now what?

• No hx of infection, trauma, previous ear surgery. No pain.

• No significant noise exposure (works as librarian)., no family hx of hearing loss.

• No hx of ototoxic drugs.

• Complains of mild dysequilibrium

• tinnitus only on left (non-pulsatile)

• Otolaryngology ROS– no wt loss– no dysphagia, no odynophagia– no hoarseness or change in voice– no globus sensation– no aspiration or sense of choking on food.

• Med Hx: Hypertension, tx with HCTZ

• Surg Hx: none

• Meds: HCTZ

• ROS: unremarkable,– good exercise tolerance

walks for 30 minutes every morning

Physical Exam

• Ears

• Nose

• Throat

• neuro

Physical Exam

• Vibrant, pleasant women

• Remarkable findings:– Ears: normal exam, – oral: symm palate, +gag, tongue mobile– no facial weakness, no facial parasthesia– TVC equally mobile, – decreased corneal reflex left eye– left + Hitzleberger sign.

• Other clinical testing?

Forks

• Weber lateralized to the right

• Rinne: right is +

• Rinne: left is +

Imp/Plan:

IMP/Plan ?

ABR vs. MRI

• Advantages/Disadvantages

• E - Eighth nerve (wave I)……….2.0 msec

• C - cochlear nucleus (wave II)….3.0 msec

• O - superior olive (wave III)……4.1 msec

• L - lateral lemniscus (wave IV)..5.3 msec

• I - inferior colliculus (wave V)..5.9 msec

What about calorics?

Treatment Options

Treatment Options

• Observation

• surgery (what approaches?)

• what about gamma knife?

Surgery

• Retrosigmoid or suboccipital• hearing conservation except lateral 1/3 of IAC

• need to retract on cerebellum/ post op H/A

• Translabyrinthine• most direct/ good exposure (including VII)

• does not conserve hearing

• Middle Fossa approach• hearing conservation, exposes lateral 1/3 IAC

Anatomy

• Cerebellar Pontine Angle– medially lateral surface of brainstem– roof cerebellum/middle cerebellar ped.– Post. Cerebellum/cerebellar tonsil– floor arachnoid assoc. with lower nn.