Transcript of Live Chat, from May 19,2002
Guest Host: Dr. Rosario Musella, Neurosurgeon at Bayfront Medical Center, St. Petersburg, Florida
Moderator: Al Musella, DPM President, Musella Foundation Location: Virtualtrials.com Auditorium

• Welcome Dr. Musella.
  Please tell us a little about yourself.
  
  I have seen four decades of neurosurgery. I am very lucky to have witnessed so much progres especially over the last two decades. One of the greatest advances is radiosurgery with the use of the gamma knife
  
  
• First question:
  What is the difference between the gamma knife and other forms of radiosurgery?
  
  The GN uses a much more ""conformal"" plan and is more precise
  
  
• What types of tumors can the gamma knife be used for?
  
  It is especially successful with arteriovenous malformations and tumors at the base of the skull, as well as acoustic neuromas
  
  
• Re: Acoustic neuromas: how do you decide between gamma knife or surgery?
  
  Based on the recent data, if the tumor is less than 3 cm, I believe that radiosurgery carries better results and much less complications than microsurgery
  
  
• Re: Glioblastoma multiofrme: Is the Gamma Knife useful for it? Should it be done before, after or instead of standard radiation?
  
  This is a question open for debate. I believe that a booster dose after conventional therapy may be appropriate
  
  
• How young a patient can you treat? There is a question about a 4 year old with craniopharyngioma Would GN help that tumor type?
  
  This should be no problem. The patient would be under general anesthesia. I understand that good results can be obtained in craniopharyngiomas"
  
  
• What are the long term side effects of the gamma knife?
  
  Side effects of radiosurgery can occur during several months after Rx, but they are usually mild and controllable with tapered doses of steroids
  
  
• Can gamma knife be used on a tumor in the speech area?
  
  With caution, and certainly more safely than with surgery
  
  
• Can you explain what the gamma knife procedure is like from the patient's point of view... like how long a day, pain, what they feel, and aftercare?
  
  The frame is applied under local anesthesia, there is little discomfort, and plenty of sedation IV, then images are obtained, then the patient goes to the site of treatment and the procedure is painless, and it lasts form 30 minutes to 3 hours
  
  
• If a person has already had the ""Maximum lifetime dosage"" of radiation, will they still be able to have the gamma knife?
  
  Probably yes
  
  
• With standard radiation, necrosis often develops after a while. Does GK also cause radiation necrosis?
  
  It can happen, but with the experience that has been gained, current dosage seldom causes unwanted necrosis
  
  
• Can the gamma knife be used on a pediatric pineoblastoma?
  
  Probably yes
  
  
• Can you compare gamma knife to fractionated stereotactic radiosurgery?
  
  The biological effect of fractionation is less effective. At times fractionation is necessary if the lesion is too large.
  
  
• Do you always need a biopsy first, for something that looks like a meningioma? Or can you just use Gamma knife?
  
  Most of the times biopsy is not necessary for meningiomas
  
  
• What kind of doctor should do the gamma knife? A radiation oncologist or neurosurgeon. Does it matter?
  
  I believe in the team approach with the neurosurgeon in charge
  
  
• Sue asks: My mother was diagnosed with Anaplastic Oligo in her left Thalamus (5cm X 4cm).We were told it was inoperable. We never pursued another opinion. Should we have? Is GK possibly an options?
  
  Yes
  
  
• Can the gamma knife be used when the tumor is irregularly shaped?
  
  The GK software allows for very precise conformal treatment to irregulerly shaped lesions
  
  
• What is your preferred treatment for a single brain met from breast cancer: surgery / whole brain radiation or gamma knife?
  
  This is being debated. I would prefer radiosurgery as first line of Rx
  
  
• Up to how many individual brain mets would you treat with the gamma knife at 1 time?
  
  This is another area of debate. I believe that size and location play a more important role. Up to 10 lesions have been Rx recently
  
  
• How would gamma knife radiosurgery compare with brachytherapy - radiation seed implants and the new gliasite system for the treatment of a glioblastoma?
  
  I think all these Rx complement each other
  
  
• Is the gamma knife considered experimental for the treatment of glioblastomas and acoustic neuromas? (In other words - does insurance pay for it usually?)
  
  I think insurers still pay
  
  
• How does a gamma knife work in the treatment of an av malformation? Is it as effective and safe as surgery?
  
  It can be safer, especially in crucial areas of the brain. It may take , however , 2 or more years for the obliteration to take place. Meanwhile rebleeding can occur
  
  
• How about for trigeminal neuralgia?
  
  I think it is very good and the results are the same as with microsurgery. The only problem is that it may take 2 months for pain relief
  
  
• Can you do anything to treat intractable seizures with the gamma knife?
  
  This area is more experimental. But it is a very exciting field, since it may be possible to inactivate the epilptic focus without creating a destructive lesion
  
  
• Can you treat tumors that are up against the ventricles? Does it matter?
  
  Not really
  
  
• For a pituitary tumor, would you prefer to treat it with surgery or gamma knife?
  
  If the tumor is large and compressing the optic apparatus, it will need debulking first
  
  
• When you ""zap"" a tumor (for example a meningioma), what happens to the dead tissue? Doesn't it cause problems?
  
  It may cause some edema, but it is usually transient and treatable with steroids
  
  
• Where can we find a list of gamma knife centers. (a few people asked: UK, Austrailia, US)
  
  I believe Elekta's website has a list (Editors' Note: it is at http://elekta.org/)
  
  
• Other than gamma knife, do you see anything new in the pipeline that looks promising for gbms?
  
  I think the answer will have to come from molecular biology
  
  
• How soon after surgery would you use gamma knife for a gbm?
  
  Within 10 days
  
  
• We are running out of gamma knife questions, so I am going to move onto surgery..."
  Statistically, what is the difference in outcome between a 100% removal of a gbm and say 90%?"
  
  Probaly not very much difference, however striving for as much debulking is the goal
  
  
• Do you like gliadel wafers? Can you do gamma knife after gliadel implantation?
  
  Yes, and I like it
  
  
• What would you say is the best treatment plan for a newly diagnosed gbm?
  
  Gross total removal, if possible, pus radiosurgery
  
  
• How about chemotherapy or immunotherapy?
  
  I don't have much confidence in chemotherapy. I am not sure of the current status of immunotherapy
  
  
• Can you use gamma knife to treat cysts ( a cyst formed after surgery and radiation for a gbm).
  
  Typically a cyst is not biologically active and not treatable with gamma rays
  
  
• Can you do gamma knife on a pregnant woman with a meningioma?
  
  I would not recommend it
  
  
• Do you think gamma knife should be part of the "standard treatment" for gbms?
  
  Probably
  
  
• Can gamma knife be used on other parts of the body other than the brain?
  
  No, and it is one of the limitations of GK
  
  
• What is the approximate cost of a gamma knife treatment?
  
  I believe about $15,000
  
  
• Can the gamma knife cure any tumors, or just delay recurrence?
  
  GK inactivates tumors, and may cause some shrinkage
  
  
• Do you ever use radiation enhancers at the same time as gamma knife?
  
  I am not familiar with the use of enhancers
  
  
• Getting back to brain mets: do you use chemotherapy after gamma knife, or just gamma knife?
  
  Just GK
  
  
• If someone has a brain met from breast cancer, can the gamma knife improve the survival times of the patient?
  
  Yes
  
  
• By how much?
  
  By doubling life expectancy
  
  
• There are so many forms of radiosurgery out there, how can one decide which machine to use?
  
  GK is more accurate, but LINACS can be very good as alternative
  
  
• Only time for 1 last question..... how can our listeners contact you to let you evaluate their case for gamma knife?
  
  They can email me at rmusella@tampabay.rr.com
  
  
• That concludes this chat.. Thank you for participating.