Gamma Knife stereotactic radiation system is one of only 300 in the world

NEWPORT NEWS:   As part of its continuing commitment to providing the most comprehensive cancer care available, Riverside Health System has added a powerful new tool to its arsenal of cutting edge technology for treating cancer patients.   On August 3rd, in its Radiosurgery Center on the campus of Riverside Regional Medical Center, a team of neurosurgeons, radiation oncologists, medical physicists and nurses treated the first patients with the newly-installed Leksell Gamma Knife ® Perfexion™ stereotactic radiosurgery system – one of only 300 such systems in the world. 

Riverside’s team was joined by Ian Paddick, M.Sc., a preeminent medical physicist and consultant at four Gamma Knife Centers in the United Kingdom, who came to Virginia specifically to help Riverside launch the Perfexion system.  Recognized as the leading authority on the Gamma Knife, Dr. Paddick praises the Perfexion™ for its unequalled conformity – precisely matching the radiation dose to the size and shape of the tumor.  “Approximately a million patients have been treated with Gamma rays worldwide,” Dr. Paddick says.  “The science is completely understood; and we have extensive medical evidence of its efficacy.”

The Gamma Knife delivers a single, finely focused, high dose of radiation to its target, causing little or no damage to surrounding tissue. Abnormalities measuring less than three (3) centimeters, or one inch in diameter, can be treated with the Gamma Knife.  Riverside installed its first Gamma Knife, the 4C system, in 2006, to provide advanced radiation treatments for patients with small-to-medium cancers, including brain tumors, abnormal blood vessel formations, and a host of other neurological conditions.

The most recent generation of the Gamma Knife, the Perfexion™ system dramatically streamlines workflow and expands the treatable volume through an automated, multi-source collimator. System benefits include faster set-up and treatment delivery to one or more tumors in a single session. Perfexion allows treatment of a wider range of targets faster and more efficiently than ever before.

The radiosurgery system’s unique collimator is a permanent device divided into moveable sectors, ensuring superior conformity, accuracy and dosimetry while reducing residual dose to unintended areas. Integrated and intuitive treatment planning software facilitates creation of even the most complex plans (e.g., a donut-shaped dose distribution) by configuring composite shots that avoid overexposure to critical structures. Perfexion is fine-tuned to the task, resulting in fast, efficient treatments, offering 98 percent reliability and unrivalled accuracy, guaranteed to 0.50mm.

The benefits of Gamma Knife cannot be overstated.  The risks associated with open surgery are eliminated, and because no incisions are required, the procedure can be performed using only local anesthesia.  Treatment can be planned and programmed within a matter of an hour or two, requiring fewer MRI sequences.  Treatment time is significantly less than conventional radiation and other delivery systems – often just one or two sessions – and because it’s most often done on an out-patient basis, most patients return to normal activity within 24-hours. 

Such was the case on Tuesday, August 4th, when a patient presented to the hospital with a history of headache and involuntary facial movement following chemotherapy for colon cancer.  When an MRI revealed two lesions in the patient’s brain, he was taken to the Radiosurgery Center and treated with the Perfexion®.  “Because of the limitations of the 4C Gamma Knife, this patient would have required two treatments,” says Dr. C. R. Kersh, a Riverside Radiation Onologist.  “It would have required him to be on the table twice, to have MRI twice and anesthesia twice.  Using the Perfexion, we treated the entire area in 56 minutes.  The reduction in time, cost and inconvenience for the patient is outstanding.”

Describing the procedure the following day, August 5th, the patient reported experiencing no pain of any kind.  Instead, he said, “The care I received was phenomenal.  I was comfortable the entire time.  They even asked what type of music I liked, so I listened to classical music all during the procedure.  The doctors and nurses were attentive and caring, and I left feeling very confident.”  As for lingering side effects, he reported none, and in fact, went shopping at Costco the next day.

“The Perfexion is going to expand our ability to treat brain tumors,” says Martin Richardson, MS, DABR, RSO, a medical physicist with Medical Radiation Physics, Inc.  “It’s a multidisciplinary, collaborative treatment now, especially for patients with multiple metastases to the brain.  Five years ago, we would have to treat such a patient surgically.  Even when using the 4C Gamma Knife was appropriate, treatment would be long and protracted. Now with Perfexion, we’ll be able to treat these patients with multiple brain tumors far more quickly and efficiently.  In the United States, the standard is eight to 10 tumors, although we know that far more than that have been treated effectively.”

There are other applications for the Perfexion™ system as well. “Another benefit is that Perfexion enables us to treat a wider variety of presentations,” says Dr. William H. McAllister IV, a Riverside neurosurgeon.  “With the 4C, there were geographic limitations in that it was designed to treat only the middle of the brain.  As the technology has evolved, we’re now able to treat tumors that occur not just in the middle of the brain, but also along the sides as well.  And we can also effectively treat tumors that form at the junction of the brain and the spinal cord.”

The cancer team can generally detect responses as early as two weeks after treatment.  Customarily, they waited six to eight weeks to reimage patients after treatment with the 4C Gamma Knife system.  Results are expected earlier using the Perfexion system. 

From the perspective of the attending nurses, the acquisition of the Perfexion system makes the patient’s experience easier, resulting in far less anxiety and concern.  “Because the beam can be directed internally, there’s no time spent repositioning the patient’s head as different areas are treated.  The treatment time is much shorter,” says Monica Diggs, RN, who assisted with the first procedures.  “It’s very smooth and quiet, and if patients need help relaxing before and during the treatment, we can accommodate them easily.  And they’re much more comfortable now.”

The acquisition of this technology by Riverside is further proof that cancer patients in the community need not leave Hampton Roads to receive world class medical care.

About Stereotactic Radiosurgery Considered the gold standard for brain tumors and abnormalities, stereotactic radiosurgery was introduced in 1951 by Dr. Lars Leksell.  He understood that the nervous system doesn’t tolerate radiation as well as other parts of the body; thus his discovery has led to methods of limiting the toxicity of radiation to normal healthy tissue, while maximizing the amount of radiation that can be given to malignant or neoplastic tissue. No other non-invasive treatment method in the field has greater clinical acceptance anywhere in the world.

About Gamma KnifeTheGamma Knife is used for patients with brain tumors as well as other conditions, such as arteriovenous malformations, trigeminal neuralgias or vestibular schwannomas (acoustic neuromas.)   Often mistaken by patients as utilizing actual surgical knives making incisions, the Gamma Knife Perfexion is 192 beams of radiation all coming on at the same time and meeting at one very carefully calculated point in the brain.  Invented in 1967 by Dr. Leksell with Drs. Ladislau Steiner and Borje Larsson, the Gamma Knife administers high-intensity cobalt radiation therapy that concentrates the radiation over a small volume.

During the procedure, patients are given numbing medicine, which allows the surgeon to fix their head in a specially fitted frame, devised by Dr. Leskell and bearing his name, which is secured by four pins attached to the skull.  The frame is then locked into the Gamma Knife and treatment ensues.

About Riverside Health SystemThe original charter for Riverside dates back to December 15, 1915. The company began as one hospital, founded by the community and built on a site at Huntington Avenue and 50th Street in Newport News, Virginia. In 1962, the hospital was relocated to the present site of Riverside Regional Medical Center in central Newport News. Since then, Riverside has evolved into a flagship regional medical center with affiliates throughout the region in every aspect of healthcare. Riverside is a 501c(3) tax exempt, non-profit organization dedicated to improving health and saving lives. Riverside Health System is governed by a voluntary Board of Directors, as is each of the Riverside affiliates throughout the region. Through the dedication and tireless energy of our employees, physicians and volunteers, we assure that the needs of the community are met in every Riverside endeavor.

Published: August 12, 2015