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Q&A Sessions: Schwannoma

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.

Lee asks:
I was diagnosed with possible hemangioma or schwannoma after progressive hearing loss and pulsatile tinnitus in right ear but it has taken four doctors to classify the enhancement as such. Would Gamma Knife be considered in this scenerio? If so, can it preserve hearing and/or deal with the pulsatile tinnitus?

Dr. Lee responds:
Gamma Knife Radiosurgery can be used to treat benign brain tumors including schwannomas. I would be happy to review your films.

Mary in AZ asks:
I have a 1.1cm vestibular schwannoma. I still have hearing albeit distorted on the affected side. What is the difference in Gamma Knife versus cyberknife in chances of hearing retention? I have the option for either here.

Dr. Lee responds:
There are many reasons why Gamma Knife is superior to other technologies. For example, Gamma Knife has the longest proven track record for treating acoustic neuromas. It is the gold standard by which all other competitors are measured. The Gamma Knife is designed only to treat brain lesions and therefore the users of Gamma Knife are focused on brain lesions. Nothing is more accurate than the Gamma Knife. All other competitors always compare themselves to Gamma Knife.

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.

Diane asks:
My 78-year-old mother was recently diagnosed with a schwannoma vagus, which is close to her carotid artery. Is Gamma Knife something that could help her or would she require traditional surgery?

Dr. Lee responds:
Gamma Knife can definitely be used in this situation with great success and safety. If you would like to schedule an appointment, please call us at 800-789-PENN or you can also request an appointment online.

Dave asks:
For a 3.0 cm dumbell shaped schwannoma of the jugular foramen, is the preferred treatment operative, gamma knife, or other?

Dr. Lee responds:
Gamma Knife is the preferred treatment for schwannomas of the eighth nerve if the tumor is small or medium-sized. Schwannomas of the lower cranial nerves also respond favorably to Gamma Knife, and I would be happy to review your films to determine eligibility for Gamma Knife.

Jeff asks:
I had a 4.2 cm jugular foramen schwannoma removed in December of 2005, it now is growing back. Is it better to wait and watch or have Gamma Knife as soon is possible.

Dr. Lee responds:
Timing of the procedure depends upon each individual's unique situation. I would be happy to review your case.

Natasha asks:
I have been diagnosed with a vestibular schwanoma 12mmx7mmx5mm. I have extreme vertigo and debilatating dizziness but minimal hearing loss. Can Gamma Knife help my symptoms within a reasonable amount of time or shall I expect them to worsen before improving?

Dr. Lee responds:
For your size tumor, Gamma Knife has been shown to have the best results with respect to hearing loss, facial nerve preservation, and quality of life as compared to conventional surgical resection. You are a great candidate for Gamma Knife, and I would be happy to discuss the specific advantages and disadvantages.

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

Rick asks:
My physician has said I have either a trigeminal schwannoma or a meningioma. Can the Gamma Knife be used to treat these conditions?

Dr. Lee responds:
Gamma Knife can control benign tumors such as meningiomas and schwannomas >90% of the time at a follow-up time period of ten years. Longer term results are still being collected.

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

Stan asks:
I was diagnosed with a Schwannoma 4cm(h)x 1.5cm(w)x 2.4cm(d). From MRI & Angiogram, acoustic neuroma/glomus jugulare/glioma were ruled out. It is located within left cerebellopontine angle with significant inferolateral extension into the region of the jugular foramen. Giving the size of the tumor, would I be a good candidate for Gamma Knife instead of surgery?

Dr. Lee responds:
Most cerebellopontine angle tumors can be treated with Gamma Knife. However, in your specific case, I would want to review the films and your clinical exam prior to making any specific recommendations.

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

Raaghavendra asks:
I had been operated on for left Cp angle schwannoma eight years ago. Post-operative complications lead to CSF leakage and subsequently took attempts to stop it. I'm presently diagnosed for jugular foramen schwannoma of 3-5cm in size. I consulted several neurosurgeons and most of them are against Gamma Knife treatment.

Please let me know the complications (if any) or if you need more information from me. Please suggest the best solution for these type of tumors. Presently I am asymptomatic. What I have understood from the report is that tumor is both inside and as well outside the cranial activity. Please advice the best solution.

Dr. Lee responds:
Gamma Knife for larger tumors like this is very difficult, because of potential complications. In addition, it appears that you have a genetic predisposition to develop tumors and thus the success rate of Gamma Knife may not be very good.

Rita asks:
I am 35 and diagnosed with a seventh nerve schwannoma. It has grown 1mm in five months. Is the Gamma Knife procedure successful with these tumors?

Dr. Lee responds:
Gamma Knife radiosurgery can control vestibular schwannomas (acoustic neuromas) which arise from the eighth cranial nerve. Although the diagnosis and thus experience with seventh nerve schwannomas is not as bountiful as that with vestibular schwannomas, there is every reason to believe that Gamma Knife should be successful in managing these tumors.

Please call 1-800-789-PENN (7366) to schedule an appointment. You can also request an appointment online.

Ellie asks:
My friend has a trigeminal schwannoma compressing the brain stem notably. I am wondering if Gamma Knife is an option. Most of the mass is cystic.

Dr. Lee responds:
Gamma Knife radiosurgery is definitely an option for trigeminal schwannomas as long as the size of the tumor is appropriate.

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

RWilson asks:
I have been diagnosed with benign trigeminal schwannoma (2.5 x 3 cm) located cavernous sinus within 2mm of optic nerve. The surgeon has recommended Gamma Knife versus craniotomy at this time. Can you give me information as related to surgery versus the Gamma Knife? They said that within 3 mm of optic nerve is risking damage to eye function, in my case double vision.

Dr. Lee responds:
Without seeing the films, it is difficult to advise you. However, there is a big difference between the radiation sensitivity of the optic nerves and the oculomotor, trochlear, and abducens nerves. The optic nerve (II) is very radiation sensitive which can result in blindness. Fortunately, the optic nerve is unlikely to be damaged when performing Gamma Knife for a trigeminal schwannoma, because it is located farther away.

In contrast, the oculomotor (III), trochlear (IV), and abducens (VI) nerves are very radiation resistant and damage to them would result in double vision. During the Gamma Knife radiosurgical procedure, these nerves receive high doses but are unlikely to be damaged, since they are radiation resistant.

MAA asks:
Beaumont Hospital in Royal Oak, MI. received their Gamma Knife 4/5 months ago. I was diagnosed with acoustic nerve schwannoma in my left ear measuring 1.3cm x 275mm. My doctor advised that I am a good candidate for this procedure. I asked him how many procedure he has performed and he said 20. My doctor wants to monitor the growth for 8 months. My balance is off, I have no pain, or numbness in my face and no slurring of speech. I fell downstairs in January 07 and fractures my ankle and leg. After the cast came off I was so dizzy. About two months ago I woke up not able to hear the traffic. I had a MRI, MRA, Doppler, ENG I have loss of hearing (45%) and there is a nervousness in the ear area. How many operations for an acoustic tumor have you performed? Why am I being monitored? Whoever performs this procedure on me must be fully experienced.

Dr. Lee responds:
We perform approximately 40 Gamma Knife radiosurgical procedures for acoustic neuromas per year at the Penn Gamma Knife Center. In addition, we perform approximately 250 Gamma Knife radiosurgical procedures total per year. I would be happy to discuss your case with you. Please contact my office to arrange a phone consultation.


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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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