Gamma Knife Radiosurgery

The fact is, the Gamma Knife is not really a knife at all, but a non-invasive tool that replaces the scalpel with a focused array of 192 intersecting beams of high-intensity gamma radiation. Hoag Memorial Hospital is one of the first in the nation to have the absolute state-of-the art fully upgraded Gamma Knife Perfexion™. Treatment times are shorter, accuracy is even better than its most accurate predecessor and outcomes will be even better. The Perfexion™ delivers 100 times less radiation to normal tissue than the latest CyberKnife™. Worldwide, there is 10 times more experience with the Gamma Knife than with any other “knock-off.”

Gamma Knife Perfexion

The new Gamma Knife Perfexion


The Gamma Knife concept originated in Stockholm in 1951, when Dr. Lars Leksell, a prominent neurosurgeon, coined the term “Radiosurgery.” Dr. Leksell was a pioneer in “Stereotaxy,” a procedure which allows the neurosurgeon to locate and reach any point of the brain to within a single millimeter of accuracy, using trigonometry to navigate the brain’s 3-dimensional space.

Consequently, in lieu of performing open surgery on the brain, the neurosurgeon has the ability to precisely focus gamma radiation on a target tumor or vascular malformation. Focused radiation may also be used to treat “functional” disorders such as the tremors resulting from Parkinson’s disease, and the pain syndrome of trigeminal neuralgia.

Gamma Knife Intersect Precisely

The photon beams of the Gamma Knife intersect precisely on the target.


Contrary to conventional radiation therapy, which must be delivered in small fractions over time (often over as many as six weeks), and in which normal brain tissue is exposed to approximately the same amount of radiation as the tumor target, Gamma Knife radiosurgery employs a greater number of lower level radiation sources (201) arranged in a collimator Helmet. The neurosurgeon intersects these beams on the target.

Gamma Knife Works

Each beam is very weak, passing through an area of the brain different from all of the other beams. Thus each beam is safe to normal brain tissue but where they focus is 200 times as powerful as each individual beam.


In order to focus the beams precisely and accurately, the patient must be fitted with a painless “stereotactic frame” prior to the MRI and Gamma Knife procedure.

Painless Stereotactic Frame

The painless stereotactic frame allows accurate focus. Upon removal, the pinsites are essentially invisible a week later.

The combined effect at the intersection of the beams is 201 times as powerful as each individual beam, and can obliterate tumors and vascular malformations in a single treatment.


Gamma Knife radiosurgery is not experimental. The first Gamma Knife treatment was recorded in Sweden in 1968, and since then nearly 20,000 patients per year are being successfully treated worldwide.

Gamma Knife radiosurgery has been performed on American soil since 1987 and by Dr. Duma in Southern California and the East Coast since 1990. He has performed approximately 220 Gamma Knife procedures per year since that time. The medical literature is replete with hundreds of articles relating to Gamma Knife radiosurgery that is considered the “gold standard” of radiosurgical technique.

If you wish to make a consultation appointment with Dr. Duma, or for further information regarding Gamma Knife radiosurgery in Los Angeles, please register on our website. Also, you can reach us at 949-642-6787.

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'I was given a couple of months to live. Dr Duma is brilliant.'

Eric Muranaka
Malignant Brain Tumor
8 year survivor

'Thanks to Dr. Duma, my brain tumor has completely diminished.'

Victor Pimenta
Anaplastic Astrocytoma
14 year survivor

'He was knowledgeable and patient when addressing my concerns!'

Allison Smith-Conway
Parkinson's Disease
Symptom free 2 years

'I am alive today because of Dr. Duma.'

Lindsay Susskind
Glioblastoma Multiform
6 year survivor

'The standard of care Dr. Duma offers is stellar. '

Paul Roberts
Glioblastoma Multiform
6 year survivor

'You have extended my life, not only in time, but also the quality of life.'

Richard Teter
Glioblastoma Multiform
2 year survivor

'He is always concerned for my well-being. I trust him with my life!'

Kathy Hyams
Breast Cancer Brain Metastases
10 year survivor

Dr. Duma Patented Radio Surgery