Intracanicular - ??

[lrobie]

So I met with a new neurosurgeon yesterday...the one that I had asked if anyone had heard his name, Raymond Sekula.  He relocated to Erie from Pittsburgh last year.  People go to him from around the world for what he specializes in; facial nerve problems and decompression surgeries.  He also has treated ANs while at Allegheny General.  Well, he told me that he would recommend middle-fossa, but he couldn't do mine because there isn't a neurotologist in Erie and he would need one to assist him in the surgery because of the type (mid-fossa).  He is recommending that I go see Dr. Lunsford for possible radiation and that I also go to the Balance Disorder Center to have a vestibular evaluation.  My dizziness/balance is getting worse.  He said I should go there first and then go see Dr. Lunsford. 

My question - he said that my tumor is intracanicular and is totally in the IAC.  He said that my tumor is either surrounding all the nerves there or that the nerves were surrounding the tumor and that something (?) would have to be peeled away.  He made it sound like with where my tumor was located, it was going to be awfully difficult to do surgery without the complications.  What does intracanicular mean?  Also, I just thought that ANs were either in or out of the IAC, or both, and if big enough sometimes compress on the brain stem.

So, yet again, I'm back to not knowing what I'm doing.  Don't get me wrong.  I feel like Dr. Sekula was very knowledgeable and spent a lot of time with me.

Lisa

P.S.  I also found out within the past week that Dr. Sekula did decompression surgery on one of my coworkers who has had hemifacial spasms for the past seven years.  It was two weeks ago and he is back at work and is 98% better at this point.  Just a suggestion for anyone who is looking for a doctor who specializes in that.

[producer]

Hi LIsa, intracanalicular means the tumor is completely inside the IAC, much like mine.

This has it advantages but also its disadvantages.

Main advantage ofcourse is that for the tumor to fit inside there it means its small, under 1cm or thereabouts.

The disadvantage is that because the average human IAC width is around 9mm the tumor presses harder on the nerves once the IAC is filled than say a 2cm tumor thats outside the IAC and has room to grow.  Thats why often people with small tumors can have worst symptoms than others with larger ones.

Intracanalicular tumors close to 1cm can basically be compressing the nerves much like a 3cm CPA (outside the IAC) tumor may be compressing..  Ofcourse a larger one has more implications to surrounding nerves (trigeminal, facial) and most importantly brainstem compression. 

Also the closer to the cochlear fossa (right next to cochlea) that the AN is the harder it becomes to save any hearing.

All in all having a small intracanalicular AN isnt the worst AN configuration (i know that sounds funny) to have it but it comes with its own drawbacks..


hope this info helps


chris

[rupert]

Hi Lisa,
            An's are also called vestibular shwannoma's, because they grow off the sheath of shwan cells that cover the balance nerve.  This is why that nerve is usually cut during surgery to completely remove the tumor.  The hearing nerve , balance nerve , and also the facial nerve are all in close proximity in the IAC. So , yes they are all kind of intertwined .  The tumor usually starts at a point where the nerve bundle enters the IAC.  Thus small AN's are inside the IAC.  As they grow, they can either put pressure on these nerves or suck away their blood supply, AKA hearing loss and balance problems.   As the tumor gets bigger it can expand out of the IAC and into the space between the IAC and the brain.  If it gets big enough it will compress the brainstem.  Protocol these days puts emphasis on preserving the facial nerve by not peeling it all off, but leaving a sliver of the tumor and then following up with GK or CK.  Hope this helps.

[lrobie]

Thanks for the explanations.  They do make sense to me.  Unfortunately, when I came home from work today, I had received the written report from my MRI on 2/7/12.  I was initially told there was no growth.  Now I'm reading that, even though it might be a small increase, there has been some growth.  My findings read as follows:  Again seen is a small extra-axial enhancing mass centered in the left IAC, slightly protruding through the porous acousticus and extending nearly to the level of the fundus.  On 8/1/11, it measured 9.9 x 4.6 x 9.5 and now measures 10.5 x 5.3 x 9.9.   

It sounds like it is protruding through now.  When I saw Dr. Sekula yesterday, he didn't know the results of the 2/7/12 MRI.  I wonder if this would change his mind now. 

Thoughts??

Lisa

[rupert]

Hello again Lisa,
    Here is something that I found interesting with my MRI reports.  If you have several people look at them, they all seem
to come up with a different size.   Example:  My first MRI before treatment showed 1.6cm x 2.6cm.  That was from the radiologist.  UPMC came up with 1.6 x 2.2 cm.   At one year MRI,  the radiologist report said it was the same size as before and looked the same.  UPMC said it had gotten smaller and showed signs of necrosis.  At two year MRI the radiologist said it was still the same size as first MRI and showed no change.  UPMC said they were very happy to see it smaller yet and it was starting to come off the brainstem a bit.   As you can see there are two interpretations here.  One,  well it's okay but not great and the other is obviously very good news. 

[lrobie]

What I don't understand is why radiation would be recommended if your tumor has filled the entire IAC and is already pushing on your nerves.  When the tumor initially swells, won't it cause even more problems?  And, if the swelling doesn't go down soon after, it seems to me that your problems would become more permanent.  Sorry, all these things running through my mind.

Lisa

[producer]

Lisa, the same dilemma (and possibly worse) will be encountered with surgery in an IAC  tumor.  Because a small intracanalicular tumor is already pressing on nerves it would make surgical removal more vulnerable to nerve damage (permanent).

I guess with radiation you have the hope that the side effects are temporary



chris

[producer]

I think that with intracanalicular tumor specifically the exact size of the tumor makes a big difference.

Since the average IAC is about 9mm  i guess removing a 5mm may make a big difference compared to removing a 9mm one.

[lrobie]

I'm not sure why, but I guess I never realized that an AN could grow in two different areas (IAC or CPA).  I assumed that they started in the IAC for everyone.  Do you think it's beneficial to know this upon diagnosis so that you can make a more informed decision?  If I would have known that it was completely in the IAC and that the IAC was a small space to fill, maybe I would have sought treatment right away so the later symptoms or complications wouldn't be as bad.  It seems that having radiation at this point is a guarantee that I will have those complications.  Maybe the research that I have done really wasn't thorough enough.  Yes, I'm second guessing myself. 

[producer]

Lisa im having the same thoughts as you. My AN is more or less the same, size and location.

There are people who have lost completely their hearing and/or are greatly troubled by dizziness with very tiny tumors so dont beat yourself up with thoughts such as  '..had i know this..i wouldve done this.." etc..

You never know, and every AN, even identical size/location/growth rates etc..will affect each person in a very different way.

Making the decision we feel most comfortably right now with the information that we have is all we can do really ; )


all the best


chris