DEBULK and RADIATE - Can that save hearing?

[v357139]

Found this paper today...

Intracapsular decompression or radical resection followed
by Gamma Knife surgery for patients harboring a large
vestibular schwannoma
http://thejns.org/doi/pdf/10.3171/2012.6.GKS12697

Please note that this is NOT classical Debulking,
This is just sucking/munching out the middle of the tumour and leaving the tumour skin behind, stuck to the facial nerve and the brainstem.

Maybe worth further discussion with your doctors

I sent the article to two doctors, including Kondziolka.  I am no doctor, but I thought Kondziolka said you had to stay below 5 gray for hearing preservation.  They used 12 gray in this article.  We'll see what those doctors say.

[PaulW]

12Gy is the dose to the edge of the tumour.
5Gy refers to the maximum amount of radiation the cochlear might get before hearing preservation rates decline.. While people get the impression that radiation is accurate to less than a millimetre.
Lots of surrounding tissue receives radiation too. The cochlear is very sensitive to radiation and is normally only a few millimetres away from the AN. Which means it often receives quite a lot of radiation.

[nftwoed]

Hello;
    I've read with SRS, radiation is absorbed as far away as 1.5 cm. from target. Another web site stated < 2.8 gy. to the cochlea did not damage the ciliary hair.

[PaulW]

Hi;

   I'm surprised just the decompression didn't help somewhat. A regular AN always displaces the nerves to the tumor surface. An NF-2 AN invades the nerve. Sci-fi: "We will assimilate you".

   "I have read a paper on pubmed where they were operating and just breaking open the Internal Auditory Canal to relieve pressure on the nerves and give the tumour room to expand and then radiating the tumour to improve hearing preservation rates.. I don't remember exactly what the results were... They were not revolutionary."  - Offered by Paul, was it?

Thanks nftwoed, I stand corrected, you are right.
NF2 tumours can invade the facial nerve.

http://books.google.com.au/books?id=RniyoXeNmMwC&pg=PA1826&lpg=PA1826&dq=nf2+invade+facial+nerve&source=bl&ots=cW1iKq9fAi&sig=p2AOZX2F3K57NIynvq9et1aUN5I&hl=en&sa=X&ei=teezUejQEIbjkgX0loCACw&ved=0CEAQ6AEwAw