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Q&A Sessions: Arteriovenous Malformation (AVM)

John Y.K. Lee, MD, Assistant Professor of Neurosurgery, is the Director of the Penn Center for Cranial Nerve Disorders and a national leader in treating cranial nerve disorders.

Sherri asks:
I have a friend who had the Gamma Knife radiosurgery done eight years ago for an arteriovenous malformation (AVM) located at the low temporal occipital junction on the right, and had two seizures, one following the other about a week ago. She was under some stress at the time. Could that have caused the seizures?

Dr. Lee responds:
It is possible that stress could have contributed to her seizure; however she should be sure to get a new MRI scan and follow-up with her physician.

Brenda asks:
I have a left 6cm temperal/parietal arteriovenous malformation (AVM). I had two embolizations done but there is still 10 percent that could not be treated because it is too deep and the vessel is huge. I also had several 9mm intranidal aneurysms. I have severe headaches everyday. I have to go for speech therapy because I can't remember my words. My eyes get blurred daily and my right side stays numb. Would I be a candidate for the Gamma Knife? If I just leave the rest of the AVM alone without any more treatment, am I at more risk for a rupture?

Dr. Lee responds:
Gamma Knife Radiosurgery may be a treatment option. I would be happy to review your films.

Sara asks:
My mother was diagnosed with an AVM when she was 25 (she is now 50). Originally she was told that her AVM was unable to be operated on based on its location and size. Over the years, she has seen neurologist after neurologist and nobody seems to be able to manage her pain, migraines and psychological side effects. I know your specialty is in the Gamma Knife radiosurgery - but do you do have consultations on AVM's and potential treatments? If not, please refer me to someone at HUP who could. Thanks!

Dr. Lee responds:
I would be happy to see your mother in consultation regarding her AVM and potential treatment options. If you have any additional questions or would like to schedule an appointment, please call us at 800-789-PENN. You can also request an appointment online.

Mark asks:
I had Gamma Knife in Dec. '04 for AVM in the left occipital lobe. In May of '05, I had a Grand-Mal Seizure. With this, I dislocated my shoulder, tore my rotator cuff and broke the upper bone in my arm. I spent a week in the hospital to fix my arm/shoulder. Since this time, I have had a seizure every May for the past 3 years. I am now on and upto 600mg of Lamictal and 500mg of Dilantin a day. I have only had one issue since this last increase. Where now? We were not told about the possilbe seizures after the Gamma Knife procedure and did not get put on medicine till the first seizure. I am running out of time and energy. I am lost.

Dr. Lee responds:
Seizures are a side effect of any procedure in the brain, including Gamma Knife Radiosurgery. In addition, Arteriovenous Malformations in your brain make you more susceptible to seizures.

SO asks:
My wife had a embolization for AVM the last three months (July 12, 2008. Did the follow up Angiogram on Oct. 31, 2008.) The result is 90% success. But the doctor advised that she needed to do the 10% for Gamma Knife. It is necessary to do? Also what are the side effects for this treatment?

Dr. Lee responds:
Embolization alone is usually not a permanent cure for AVM. Surgery or Gamma Knife Radiosurgery can provide cure.

Janine asks:
I have just found out I have an arteriovenous malformation (AVM) left frontal parietal with max dimensions approximately 3cm. The doctors also state that it is superficial venous draniage to SSS and no feeding aneurysm.

We have a follow up appointment to see the doctors. They believe that Gamma Knife treatment could work? How effective do you think this would be? They picked the AVM up after doing a scan as I had been getting bad headaches for approximately three weeks. My husband and I are very scared we just want it to be fixed. Surgery is not an option. Are there side effects to Gamma Knife treatment? I am a 35 year old female.

Dr. Lee responds:
Gamma Knife radiosurgery has an 85 percent success rate for AVM. Side effects are all related to the location of the treated AVM and the dose used. Based on the information provided, Gamma Knife radiosurgery is likely a good treatment option for you.

Christy asks:
I had Gamma Knife radiosurgery done in April 2005 for a large arteriovenous malformation (AVM) located deeply on the right side of my brain. After three years out, it is now approximately 1x1x2. What are the chances of needing treatment again?

Dr. Lee responds:
Surgery and repeat Gamma Knife radiosurgery are both options in this setting.

Tricia asks:
I understand the cut-off for Gamma Knife is 3cm. My acoustic neuroma is 2.2 x 2.9cm and located in the CP angle. There is "moderate mass effect" on the brain stem, but i don't have symptoms of compression.

I know I am a borderline case. I wonder if Gamma Knife will be effective (given the size) and safe (given the effect on the brain stem). I also have the option of treatment with a linear accelator (fractionated).

Can you please give me your thoughts on my suitability for Gamma Knife?

Dr. Lee responds:
There are other considerations, not just size of the lesion, in deciding whether or not to use Gamma Knife radiosurgery for treatment. Some of these are your age, any co-morbidities, other medical risk factors, and personal choice. Gamma Knife radiosurgery may be a reasonable option for you.

If you would like to discuss this further, please call 800-789-PENN (7366) and ask to be connected to Dr. John Y.K. Lee's office. You can also request an appointment online.

Tambo asks:
I had an 8mm acoustic neuroma surgically removed in 2003 but it has now reoccurred. Is either Gamma Knife or chemotherapy an option for me or would it be better to have surgically removed a second time.

Dr. Lee responds:
Gamma Knife radiosurgery is an excellent option for acoustic neuroma recurrence after conventional surgery.

If you have any additional questions or would like to schedule an appointment, please call us at 800-789-PENN. You can also request an appointment online.

Tennakoon asks:
My wife went through Gamma Knife for an acoustic neuroma two years ago and it was originaly 2.5 x 2.8 x 2.5. Then, after the Gamma Knife, it came to 2 x 2.5 x 2 and the most recent scan (MRI) shows a 2 x 2.8 x 2. What can we do about it now? It's been 2.6 years since the Gamma Knife.

Dr. Lee responds:
Acoustic neuromas follow a typical pattern after Gamma Knife radiosurgery. After Gamma Knife radiosurgery, some acoustic neuromas remain stable in size, some swell and then subside, and only 5% increase in size.

If you have any additional questions or would like to schedule an appointment, please call us at 800-789-PENN. You can also request an appointment online.

Joe asks:
I have an eight year-old daughter that has an arteriovenous malformation (AVM) the size of a pea. The doctors have given me the option of brain surgury or the Gamma Knife. I would like to know the risks and side effects of the Gamma Knife compared to brain surgury.

Dr. Lee responds:
This is a difficult question to answer over the internet, because risks in neurosurgery depend heavily on the location of the lesion.

If you would like to discuss this further, please call 800-789-PENN (7366) and ask to be connected to Dr. John Y.K. Lee's office. You can also request an appointment online.

Yoshida asks:
My son had a craniotomy in October 2007 to remove an arteriovenous malformation (AVM). Last Friday his doctor told us that he still has an 8mm AVM. He is suggesting embolization. Would Gamma Knife be better? The location is frontal right lobe.

Dr. Lee responds:
In this situation in an adult, Gamma Knife radiosurgery would be a definitive procedure to cure him, however the decision to use Gamma Knife radiosurgery much depends on your son's age.

If you have any additional questions or would like to schedule an appointment, please call us at 800-789-PENN. You can also request an appointment online.

Mary Ellen asks:
My daughter, 25, was diagnosed with a dural AV fistula in November of 2005. She has been under the care of a local neurosurgeon who has treated her with embolization. She has had 5 procedures (embolizations) since April 2007, the last being yesterday in August 2007.

She has been told at least two more, and if desired results are not obtained she could be looking at surgery. Do you think Gamma Knife radiosurgery would be an option for her, other than open cranial surgery.

Dr. Lee responds:
Gamma Knife radiosurgery is definitely a less invasive option for dural AV fistulas. Success rates are similar to the results for arteriovenous malformations.

Megan asks:
My 29 year old husband was diagnosed with a 3x3x2 AVM in the anterior carotid artery. Apparently the location of the AVM is difficult to treat (the area includes his vision and speech abilities). My husband does not have any symptoms except that 3 months ago he had a severe headache for 3 days, which caused him to go get an MRI, followed by an MRA, followed by an angiogram.

After the angiogram, the doctor in NYC recommended a conservative approach which is to continue with MRI's every year under a Nova Study. However, we'd like to get a second opinion. Would this AVM be a candidate for the gamma knife? If no symptoms are presenting now, is it too risky to do gamme knife surgery?

Dr. Lee responds:
An arteriovenous malformation of that size is definitely a candidate for Gamma Knife radiosurgery. Some of the theoretical benefits in this situation is that Gamma Knife induces gradual closure and obliteration of the arterial feeders to the AVM and thus minimizes complications to the surrounding brain. I would be happy to review his case.

Jess22 asks:
My husband was diagnosed with a 4.5cm AVM behind the brain stem and beneath the posterior fossa it is deep seated and has a large collateral blood supply.

We have seen 4 different doctors and recieved mixed recommendations. The first doctors said that there is no treatment available and the others recommended Gamma Knife but never discussed risks associated with the procedure and likelihood of cure.

In your experience have you known Gamma Knife to be helpful with these lesions, what is the % for risks, what are the risks, and how many treatments would a lesion of this magnitude require? The AVM has never bled it only caused mass effect hydrocephalus so we are unsure of what path to chose. Thank you, also do you have any Neurosurgeons that you recommend in the Midwest?

Dr. Lee responds:
This is a very complex situation, and I would consult as many experts in the field as possible. Please feel free to contact my office, since I would be happy to review your films and speak with you about the risks of the procedure.

If you would like to schedule an appointment, please call 1-800-789-PENN (7366) or request an appointment online.

Giles asks:
Is the Gamma Knife effective for treating tangled blood vessels? If AVM fistula isn't treated what is the survival rate?

Dr. Lee responds:
Gamma Knife is very effective for treating tangled blood vessels, eg. Arteriovenous malformations. It can obliterate them usually within two years.

Arteriovenous fistulas are different from arteriovenous malformations, but they can also be treated with Gamma Knife. The success rate is dependent on many factors.

If you would like to schedule an appointment, please call 1-800-789-PENN (7366) or request an appointment online.

Forever asks:
Can right temporal brain's AVM about 3-4 cm be treated by Gamma Knife radiosurgery?

Dr. Lee responds:
Yes, Gamma Knife is a good treatment for AVMs that are deeply located and small. Your AVM is on the borderline, but I would have to look at the films to determine its appropriateness for Gamma Knife radiosurgery.

For more information or to schedule an appointment, please call 1-800-789-PENN (7366). You can also request an appointment online.

Carol asks:
My husband was recently diagnosed with a 4-5 cm AVM in the right sylvian fissure. There is a possible venouse aneurysm on the posterior aspect of it. He is scheduled for an angiogram to help them decide if he would be able to have gamma knife vs surgery. Is it possible to use Gamma Knife if there is an aneurysm?

Dr. Lee responds:
There are at least two types of aneurysms that are associated with AVM's: feeding vessel aneurysms or intranidal aneurysms. Gamma Knife does not directly address the aneurysms, but cure of the arteriovenous malformation can cure the feeding vessel aneurysm without the need for a separate procedure for the aneurysm.

Also, a 4-5 cm AVM is not an absolute contraindication to Gamma Knife radiosurgery. Gamma Knife radiosurgery can be performed in a staged fashion (high doses separated by 3-6 months) in order to obliterate half the volume in one setting and the other half of the volume in another setting.

Tracy asks:
After having Gamma Knife radiosurgery in November for a <2 cm AVM in her occiptal lobe, she is now experiencing visual seizures, and must close her eyes and remain seated during these episodes. She is also suffering from an inablity to remember short term and transposes her numbers. Could this be due to swelling? She has been on anti-convulsants, and is also taking Zoloft for depression. I'm very concerned because this is worse than what she was experiencing prior to the Gamma Knife radiosurgery.

Dr. Lee responds:
The side effects of Gamma Knife radiosurgery are usually seen three to six months after radiosurgery. Usually, these side effects improve with time and by one year after radiosurgery can be completely resolved. Medications can be very helpful in this situation.

David asks:
My brother has a 1 cm diameter (approx) AVM located in a peduncle in the left cerebellum. He underwent a partial embolization which unfortunately led to a right side stroke from which he is recovering well. However, he needs radio surgery to completely obliterate the AVM.

What are the chances of permanent neurological deficit for Gamma Knife treatment of an AVM of this size and location? He is very concerned about any future treatment following the side-effects of the embolization procedure.

Dr. Lee responds:
The risks of Gamma Knife radiosurgery are related to several factors, including location, size, and dose. I would need to see your brother's angiogram and MRI scan in order to give you more precise numbers. By lowering the dose, I can lower the complication risk, but a lower dose would also decrease the chance for cure of the AVM. Hence, decision-making requires careful consideration of all these factors.

To further discuss your situation, please call 1-800-789-PENN (7366) and ask to be connected to John Y.K. Lee's office. You can also request an appointment online.

Warren asks:
What are the chances of having a reaction such as brain swelling from the Gamma Knife radiosurgery for an AVM?

Dr. Lee responds:
The risk of complication after Gamma Knife radiosurgery for an arteriovenous malformation is related to many factors, including dose, size, and location. All these factors need to be considered when performing the Gamma Knife procedure. Once the radiosurgical procedure is completed, there are only a few simple measures that can be done to minimize swelling. For example, steroids can be used to minimize the symptoms associated with swelling.

Dave asks:
I have been through many tests including a CT scan, MRI, MRA, MRV, and angiography. My local neurosurgeon says that I have an AVM that runs through my occipital lobe and he cannot do surgery because it's too deep.

I am 48 years old and have had a lifetime of headaches; this last one has continued since early December. Also, I have some vision irregularity and numbness in left fingers. I was told by my doctor that it is a small arterivenus malformation but looking at the pictures here on my computer it is not so big in diameter (maybe 1.5cm) but all over the place.

I see the doctor next Tuesday but when I check his web page it shows he specializes in operations and embolization. I would like to know if there is a way I can send some picturess to you to see if I should come there next.

I like what I read about you and you sound very sure of yourself, which I haven't heard from any doctors lately; just a lot of staring at the floor and passing me on.

Dr. Lee responds:
Small AVMs are best treated with Gamma Knife radiosurgery. Obliteration rates for small lesions like yours can be cured with the Gamma Knife. Side effects can be minimized with radiosurgery, as well.

Please feel free to call 1-800-789-PENN (7366) and ask to be connected to my office. I can review films without your having to travel here.

Carol asks:
My 24 year-old daughter has recently been diagnosed with an AVM in her left temporal lobe. She has been seeing doctors for the last year due to excrutiating headaches/head pain.

How successful has Gamma Knife been in treating (obliterating) the AVM and what is the likelihood that radiation of the AVM site will improve her headaches?

Dr. Lee responds:
An arteriovenous malformation in the brain is one of the best indications for Gamma Knife radiosurgery. The procedure is minimally invasive and very effective. There have been many patients who have been successfully treated with Gamma Knife, and these patients have been able to live full lives without the risks of general anesthesia and conventional surgery.

In addition, both seizures and headaches can be improved in patients who undergo Gamma Knife radiosurgery. I think it is fortunate that the Gamma Knife is available for your daughter.

If you would like more information or to schedule an appointment at the Penn Gamma Knife Center, please call 1-800-789-PENN (7366) or request an appointment online.


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Need an appointment? Request one online 24 hours/day, 7 days/week or call 800-789-PENN (7366) to speak to a referral counselor.

Gamma Knife and Leksell Gamma Knife are U.S. federally registered trademarks of Elekta Instrument S.A., Geneva, Switzerland. Photo credits: Susan Pardys, Elekta, Inc.

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