Hearing Loss and GK

[Girlfriend]

This is my first post...though I've been trolling this wonderfully helpful site for a few days.  My partner had her MRI today, confirming what we suspected: 12 CM x 10CM, vestibular schwannoma. Marked hearing loss (left side) but no other symptoms.  And, as we expected (since we were consulting at the U of IA hospital, a miscrosurgery center), the surgeon (M. Hansen) suggested steering away from GK or other radiosurgeries.  I understand, he's a surgeon, he's going to make a case for his approach.  But I was surprised when he stated that the hearing loss for radiosurgery was far greater than microsurgery outcomes.  I asked for an article, and he forwarded the following.

I'm wondering if anyone else can refer me to literature on hearing loss and MS vs. SRS approaches, or if others have had this discussion recently with their docs and can respond. 


Thanks all, for all your postings.  This is such a helpful resource.

********************************************
Lasak, John M. *+++; Klish, Darren; Kryzer, Thomas C. *+++; Hearn, Chris ++; Gorecki, John P. *++; Rine, Grant P. [//]++
*Department of Surgery, The University of Kansas School of Medicine; +The Wichita Ear Clinic; ++The Jack B. Davis Gamma Knife Center, Wesley Medical Center, Wichita; The Lawrence Cancer Center, Lawrence; and [//]Department of Internal Medicine, The University of Kansas School of Medicine-Wichita, Wichita, Kansas, U.S.A.
Gamma Knife Radiosurgery for Vestibular Schwannoma: Early Hearing Outcomes and Evaluation of the Cochlear Dose.[Miscellaneous Article]
Otology & Neurotology. 29(8):1179-1186, December 2008.
Objective: To evaluate the hearing outcomes for a group of unilateral vestibular schwannoma patients treated with gamma knife radiosurgery and to determine if the cochlear radiation dose affects hearing outcome measures.


Patients: Vestibular schwannoma patients (n = 33) treated with gamma knife with complete audiometric follow-up.

Intervention: Gamma knife radiosurgery and audiometry.

Main Outcome Measures: Pure-tone average (PTA), speech discrimination score (SDS), and cochlear radiation dose.


Conclusion: The PTA was significantly worse after gamma knife radiosurgery, with a mean follow-up of 24.6 months. Higher radiation doses to the cochlear volume negatively impacted hearing outcomes after radiosurgery for this group of vestibular schwannoma patients.

(C) 2008 Otology & Neurotology, Inc

[mindyandy]

Hey there and welcome to the board 
First off do you mean 1.2 by 1.0 ? 12 x 10 cm seems HUGE

If it is 1.2 by 1.0 this is still fairly small and GK I'm sure would a great option. CK is another great option. It has no head frame.

Keep us informed and ask questions.

[Girlfriend]

Oops!  MM indeed.  Boy, that would be so big.....

Thanks...

[Keeping Up]

I am new too!  I think my latest question has been just about solved (the malignancy issue) but will soon move on to the radiosurgery and future hearing loss.

I am very uncertain the impact of radiosurgery - so please tell me I am wrong, hearing loss is not as likely with radiosurgery, especially if the tumor is quite large (i.e microsurgery has a high risk of hearing loss with large tumors), however, the hearing loss can be fairly unpredictable on who it may or may not affect, and when it may occur.

Either way, will shush for now - my next step to try to understand as well.

Very good question - sometimes I wish there was a powerpoint slide of the pros and cons (and some relevant stats).

[sgerrard]

How did her doctor get "the hearing loss for radiosurgery was far greater than microsurgery outcomes" out of that?

Yes it is the case that hearing in some patients will go down (it very rarely goes up), so yes the PTA average of 33 patients will be lower. I would expect more hearing loss in patients whose treatment plans included more radiation of the cochlea, so that is not surprising either. Depending on the type of radiation treatment, though, 60-80% percent of patients with good hearing going in retain useful hearing afterward.

Surgery, on the other hand, is usually an all or nothing deal. Middle fossa surgery on small tumors can save hearing maybe 70% of the time with the best surgeons; retro-sigmoid surgery can save hearing sometimes; translab surgery virtually never does.

If she has "marked" hearing loss, the chances of saving it by any treatment do go down. How does she do on hearing tests?

Steve