What are the basic differences between Gamma Knife and Cyber Knife?

[dowdog]

I am newly diagnosed with AN (last Friday).  Have read some posts about these two types of radiological treatments but don't know the diff.

[ppearl214]

Hi Dowdog and welcome. You certainly have come to a terrific place with a wealth of information.

I believe if you go to the "Radio-Surgery Options" forum, you will see info there about the 2 forms of radiation that you mention but I'll see if I can help here and see if others chime in with their info as well.

Gamma Knife and Cyberknife:

GK - 1 dose/day treatment
CK - fractionated (usually 3-5 doses/days)

GK - metal head frame
CK - frameless (use of a mesh/mask)

radiation used = just about equal (anyone want to chime in on this as I'm really lousy at true technical data)

GK - Image guided
CK - image and robotic guided

Post treatment symptoms/after affects - run about the same. Obviously, varies from person to person but "typical" side affects are enhanced tinnitus, dizziness, balance issues, facial numbness, etc.

Hearing preservation (I believe) run about the same for both forms of treatment.

Like I said, just brief thoughts to help but I know there are many posts in the Radio Options forum and many here that have had both forms of treatment that are more than happy to share.

Know, regardless of what you decide or where and how, we are ALL here for you!   Welcome to our small little corner of the world, but hey, the drinks are good and so is the support! Great folks here!

Phyllis

[ppearl214]

dowdog, found this link for you in the Radio Options forums.. some posted that had GK and some that had CK.. hope it helps.

Phyl

http://anausa.org/forum/index.php?topic=1172.0

[Labott]

Dear Dowdog:

   The objective of both GK and CK is tumor cell destruction without having to crack open the skull and invade the cranial space.  This is accomplished by using convergent beams of ionizing radiation to cause extensive damage to the cells at the location where the beams cross. A large percentage of the beams pass right on through the skull and exit the other side (the basis of chest and tooth x-ray tomography).  Depending upon the size and location of the tumor, the preference of the physician, and the work schedule of the patient, a single dose of high intensity radiation (my treatment option) or successive doses of lower intensity radiation may be prescribed.  From a patient's standpoint, it really doesn't matter if the physician uses a neutron beam, proton beam, gamma ray, or x-ray beam.  These differ in terms of the energy per unit dose but not in terms of the ultimate outcome (vaporizing the tumor!).  What matters is how well these beams can be focused onto the tumor so that the cells that comprise the tumor get blasted and no others cells in the area do.  If this is confusing, I suggest the following demonstration to put your mind at ease.  Have everyone in your family take flashlights (or laser pointers) in hand and direct their beams all at the same spot.  Hopefully, the spot where all beams converge gets many times brighter than expected.  Now remember when we were kids, fascinated with lenses.  Did you ever hold a magnifying glass at just the right distance above a leaf that the sunlight passing through the glass started the leaf on fire?  If so, then you know exactly what the physician is trying to accomplish with GK or CK. 

-Labott

[Battyp]

good analogy labbot...

[dowdog]

Thanks for all of the good input.  I just got back from Dr. Wiet's office in Chicago.  This is my first visit to a specialist since my Diagnosis a week ago.  Wiet is a Neurotologist. (He is a surgeon but says that in every surgery there is a team of Doctors).
I said that I would prefer the watch and wait approach and if there needs to be any medical intervention, I would choose radiology first.  He said he can work with me no matter what choice I make.
 
The Radiologists report of my MRI says that the mass measures"approx. 10 x 6 mm transverse x AP x 6 mm in craniocaudal dimension. It extends to the level of the porus acousticus and bulges minimally into the cerebellopontine angle cistern."

Dr. Wiet says that I should have a CT Scan to see how dialated the bone is.
He says I should have a ENG test to see about my balance.  I failed the Romberg test in his office.
He says I should have an ABR to tell if the tumor is squeezing the hearing nerve.

Has anyone else had all these tests?  Are these standard in determining the best approach for treatment of AN?

[Battyp]

Dowdog IMO it sounds right to me.  I did a balance test and audiogram in the beginning of my symptoms presenting and it still took them a year to diagnosis me and when they did my tumor was considered large.  I was told they should have done an ABR in the beginning which I don' tknow if they did or didn't. 

So my opinion yes they are standard tests in determining the best approach of treatment. 

[Labott]

Dowdog:
   The tests were given to me prior to MRI imaging.  They are painless, easy to get through, and provide useful info for the physician.  After the balance test, you will really understand the meaning of the old comic line "Blow in my ear and I'll follow you anywhere". 
  -Labott

[Battyp]

Never heard that line before  LOL

Personally, I thought the heel toe walk was a riot.  I'm thinking the neuro's have hidden cameras in the corners videotaping for a montage on america's funniest home video.  Mine was sad...didn't even realize I couldn't do it at that time

[dowdog]

Labott and Batty,
Thanks for the feedback.  The heel-toe test was what my doc called the "Romberg" test.  My wife was with me in the office and she was blown away by how pitiful I looked trying to keep my balance!

Another thing my Doc said was that 1 in 10,000 people who choose radiation treatment for AN have their AN become cancerous.  I was not aware of this.  In fact, I thought I read somewhere on the AN website that this was a myth.  I didn't tell my Doc that.

[ppearl214]

Hi Dowdog.

Please know that AN radio-treatment potential "cancer" is not accurate. As with CK, the radiation is not "disposable" like radio-therapies that cancer patients experience.  Chances are slim to none that cancer would develope.

You can read more about it here in the "Brain" section of CK support website. I'm sorry I don't have the time to find the exact thread there, but know that you will see it there.

http://www.cyberknifesupport.org/forum/

Phyl

[jamie]

Another thing my Doc said was that 1 in 10,000 people who choose radiation treatment for AN have their AN become cancerous.  I was not aware of this.  In fact, I thought I read somewhere on the AN website that this was a myth.  I didn't tell my Doc that.

If you think about it, 1 in 10,000 is the number they quote for legal purposes, even if it was accurate, it's not bad odds. Chances of not waking up from anesthesia are .5 to 1 in 100....

[SuzeAN]

About that cancer statistic.... aren't there lifetime non-smokers who get lung cancer? I haven't read anything on such stats and have done alot of research for my AN situation; I would be wary if your doctor is using "scare tactics".


Just my $.02,
Good luck,
Cheers,
Suzan

[Labott]

Dear Dowdog:
      Your statistic about 1 in 10,000 captured my imagination.  I was told only 1 out of 1,000 people get diagnosed with an AN.  So by my calculation, one person out of 10 million folks is gonna get cancer from radiation.  The current rate for cancer in any form in the US population is a heck of alot higher than 1 in 10,000.  This statement probably means that you doctor is trying to convince you that it's safe.  Another way to view the 1 in 10,000 number is to convert it to a percentage.  You have a 0.01% chance of getting cancer from the treatment or a 99.99% chance you won't. Your best bet is to get a consult with a radiation specialist for AN. They will have the up-to-date figures.     -Labott

[Jackie canada]

Hi  I've just recently been diagnosed with a 1.9 x 2.1cm cerebellar pontine angle mass (AN) to the rest of us!  My ENT specialist was quick to diagnose the AN and refer me to the University Network in Toronto.  I set about finding out as much as could about AN's and found this great site.  So as prepared as I could be I recently met with a specialist at Toronto General, where the diagnosis was again confirmed, my options of treatment presented - very thoroughly but definetely weighted towards the Surgical Options (his specialty).  I've just received my follow up letter, I requested referrals for a second surgical opinion and a radiosurgery consultation, but one of the most disturbing things was the information included in his letter regarding complications from radiosurgery.

He quoted a 5% chance of significant facial pain that may require long-term  medication with anti-convulsants, a 5% change of experiencing significant headaches that may warrant the placement of a CSF shunt and 5% chance of facial weakness.  Finally  "there is the very remote yet real chance that 30-40 years later you might develop a radiation included malignancy", this last sentence frightened me and really made me question my leaning toward Radiation.

For my own reading and the reading I've done on this site, the complications from the Radiotherpy do not seem anywhere near this severe.  Any thoughts on this would really be welcomed,

Dazed and confused in Canada  

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