What is the LINAC Scalpel?

The LINAC Scalpel (or stereotactic linear accelerator) is a precision radiosurgical instrument that delivers a high dose of radiation to intracranial targets,with very little of the dose reaching normal brain structures.

Multiple arcing beams of X-rays are focused on an intracranial lesion. Their intersection results in a high target dose while sparing normal brain tissue. The actual, one-time, single-dose radiation treatment only takes about 30 to 60 minutes, with most patients being treated on an outpatient basis. The ability to carefully place and shape the radiation dose allows the treatment of patients with intracranial disorders too difficult or dangerous to treat with conventional surgical procedures, and there is no recovery period.

University of Florida neurosurgeons, radiation physicists and radiation therapists established one of the first LINAC radiosurgical centers in the country at the University of Florida Shands Neurological Center in 1988. The center's success has been due to the multidisciplinary effort made by these health professlonals in assessing and treating patients and in developing improved components of the LINAC System.

Radiosurgical therapy has been in existence for over 20 years at many institutions around the world. But what distinguishes the LINAC Scalpel at the University of Florida Shands Neurological Center from other radiosurgical systems is the software developed and attachments crafted by experts here. With a radiation beam accuracy of .2 +/-.1 mm, the LINAC Scalpel at UF Shands Neurological Center is believed to be among the most precise radiosurgical devices in the world.

How LINAC stereotactic radiosurgery is performed at the University of Florida

Lesion localization
The first step in the LINAC procedure is the localization of the lesion to be treated. This is accomplished byemploying the Brown-Roberts-Wells (BRW) stereotactic system. The BRW system provides aframework, relative to which the precise location of thelesion is determined.

The BRW localization ring or halo is a head frame that is anchored to the patient's scalp with plastic and aluminum set pins, using local anesthesia. The head frame's lightweight composition allows the patient easy mobility throughout the procedure. Because the lesion location is determined from radiographic measurements taken relative to the BRW system, it is critical that the head frame does not move throughout the entire LINAC procedure.

Once the head frame that is anchored to the patient's scalp with plastic and steel set pins, using local anesthesia. The head frame's lightweight composition allows the patient easy mobility throughout the procedure. Because the lesion location is determined from radiographic measurements taken relative to the BRW system, it is critical that the head frame does not move throughout the entire LINAC procedure. Once the head frame is in place, angiograms, CT scans and/or MRI scans of the head are obtained. An angiographic localizer, made of Plexiglas plates that contain 16 fiducial points as markers, is attached to the head frame. Lateral and anteroposterior angiograms are taken. The markers appear on the radiographs and later are used to calculate the lesion's location. A CT localizer, composed of nine graphite rods then is attached to the head frame. A CT scan is performed. The nine rods provide reference points which appear on the CT scan. Later, these points are used to calculate skull and brain location. This information is vital in reconstructing the skull and brain so that the radiation dose actually reaching the lesion can be calculated.

This computer program enables the University of Florida radiosurgical team to rapidly optimize treatment for brain malformations and tumors.

Dose planning

One of the most advanced computer planning systems for radiosurgery anywhere in the world currently is used in dose planning. Software developed by experts at the University of Florida can simulate the effects of any radiation treatment delivered by the LINAC Scalpel. This system allows for the planning and evaluation of a three-dimensional treatment, and the speed of the computer allows the treatment for any lesion to be quickly optimized.

The intersection of multiple arcs of radiation results in a high target dose while sparing normal brain tissue.

The radiation treatment Precision treatment with the LINAC Scalpel is achieved by the implementation of bearing systems which allow for accurate beam delivery and accurate rotation of the patient during the procedure. Metal tubes, called collimators, determine the radiation beam size; they also were designed and developed by the LINAC specialists at the UF Shands Neurological Center. Outpatient Program Once it has been determined that LINAC radiosurgery is the treatment of choice for your patient, an appointment is scheduled through the University of Florida Shands Clinic. Neurosurgeon Dr. William Friedman describes the basic principles of the procedure to your patient and invites family members to accompany your patient throughout the procedure. Your patient arrives at the Neurosurgical Specialties Clinic early in the morning the day of the procedure. The BRW head frame is applied, and the patient is transported to Shands Hospital Radiology Department for angiography CT, and or MRI scans. When these are completed, lunch is served to your patient in the X-ray outpatient holding area. The patient and family members remain here until afternoon, when the patient is transported to the LINAC Scalpel for treatment. The actual application of radiation takes only about 30 to 60 minutes. After the procedure, your patient is observed for a short period and is released to family members. Dr. Friedman examines your LINAC Scalpel patient every 12 months after treatment and writes you, the referring physician, a report each time. The LINAC Scalpel patient also receives a CT or MRI scan every 12 months and, when indicated, an angiogram to assess the success of the treatment. The actual application of radiation takes only about 30 to 60 minutes. After the procedure, your patient is observed for a short period and is released to family members. Dr. Friedman examines your LINAC Scalpel patient every 12 months after treatment and writes you, the referring physician, a report each time. The LINAC Scalpel patient also receives a CT or MRI scan every 12 months and, when indicated, an angiogram to assess the success of the treatment.

LINAC radiosurgery has made a difference for hundreds of patients. Just ask Julie Barrentine, a dental hygienist from Panama City Fla., who underwent LINAC therapy for an AVM in the left parietal lobe in the fall of 1991. "My problems started out of the clear blue," she recalled. "I was doing aerobics one day and I passed out. I had seizure-like activity. But I didn't have any other problems for another few years. Shortly after I had my first daughter, I was driving down the road with her in the car and felt like I was going to black out. I slowed down and began to pull over, but before I could park I rolled into a tree. People stopped to help me and saw me having seizures. Another night I was out with some friends for dinner and felt really strange. I went to my car and suddenly had seizures again." Barrentine consulted with her family doctor, who diagnosed the AVM while searching for the cause of the seizures. He referred her to Shands, where she consulted with neurosurgeons who said radiosurgery would be her best option. Follow-up tests indicate her AVM - a life-threatening disorder that carries with it a risk of hemorrhage - is gone. Recently she celebrated the birth of her second daughter. "A diagnosis of an AVM changes a lot of things," said Barrentine, 31. "I'm fortunate there was a procedure available to help take care of it. Now it's behind me and I don't have to worry."

Sophisticated dosimetry planning allows for the delivery of radiation to precise locations.

Lateral angiographic films show an arteriovenous malformation (AVM) before radiosurgery and complete resolution three years later

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The LINAC Specialists

Dr. William Alan Friedman, A.L. Rhoton Professor and Chairman of the Department of Neurosurgery, was born in Dayton, Ohio on April 25, 1953. He attended high school in Cincinnati, Ohio. He graduated in 1970 as a National Merit Scholar and attended Oberlin College. There he was elected to Phi Beta Kappa before moving on to the Ohio State University College of Medicine. Before graduating summa cum laude from medical school in 1976, he was elected to the Alpha Omega Alpha honor society and received the Maurice B. Rusoff Award for excellence in medicine. In 1976, Dr. Friedman moved to the University of Florida in Gainesville, Florida. He performed a surgical internship and a neurosurgical residency, from which he graduated in 1982. During residency training he did basic neurophysiology research as an NIH postdoctoral fellow (1 F32 NS0682-02). In 1982, he joined the faculty of the Department of Neurosurgery, as an Assistant Professor. He received an NIH Teacher Investigator Award (NS 00682-02), from July, 1982 - July, 1987, which funded further research into the basic neurophysiology of spinal cord injuries. In addition, this award supported the development of one of the first intraoperative neurophysiology monitoring laboratories, subsequently used to monitor thousands of neurosurgical and orthopedic surgical cases. Dr. Friedman served as Medical Director of the Intraoperative Neurophysiology Service from 1982-1992.

Dr. Friedman was promoted to Associate Professor and received tenure in August, 1987. In August, 1991 he was promoted to Professor. He currently serves as Chairman of the Department of Neurosurgery and the A. L. Rhoton Professor of Neurosurgery. He is the author of more than 160 articles and book chapters and has written a book on radiosurgery. He is a member of numerous professional organizations. Most notably, he serves as President of the Congress of Neurological Surgeons, and is the Past President of the Florida Neurosurgical Society. He is Vice-President (and President-Elect) of the International Stereotactic Radiosurgery Society. He is the Past Editor of Neurosurgery On Call, the Internet homepage of organized neurosurgery. He is on the editorial board of Neurosurgery, Contemporary Neurosurgery, and the Journal of Stereotactic Surgery.

In 1986, Dr. Friedman began collaborative work with Dr. Frank Bova, which led to the development of the University of Florida radiosurgery system. This system was subsequently patented by the University of Florida and licensed to Philips. The Philips commercial version of the system has become one of the most popular radiosurgical systems worldwide. Drs. Friedman and Bova received the 1990 UF College of Medicine Clinical Research Prize in recognition of this accomplishment. Dr. Friedman is the leader of a multidisciplinary radiosurgery team which has treated over 1000 patients, published more than 70 papers and chapters, produced many international meetings, and educated hundreds of visiting physicians. This team is engaged in many ongoing research projects in the new radiosurgery/radiobiology laboratory in the UF Brain Institute.

Dr. Friedman has been very active in the committee structure of the University of Florida College of Medicine. He has served on the Faculty Council and on the UF Faculty Senate. He was the first Chairman of the Institutional Graduate Medical Education Committee and guided the development and submission of our first Institutional Policy Review Document to the ACGME. He has served on the Council for Resource Management, the Physician Incentive Subcommittee, the Professorial Promotion and Tenure Committee, and multiple Chair Search committees. More recently, he has chaired the Level 1 Trauma Center Task Force, has served as the Medical Director of DPII, and is a member of the Clinical Practice Committee.

Dr. Friedman has been cited, since 1992, in the book, "The Best Doctors in America," and was listed in Good Housekeeping (10/92) as one of the "400 best cancer specialists in America."

Frank Joseph Bova, Ph.D. was born in New York City on March 19, 1950. He attended Sawanhaka High School in Elmont, New York graduating in 1968. He attended Renesslear Polytechnic Institute and in 1972 graduated with a Bachelor in Biomedical Engineering and in 1973 a Masters in Biomedical Engineering. He went on to receive a Ph.D. in Nuclear Engineering Sciences with a specialization in Medical Physics from the University of Florida in 1977.
In 1978 Dr. Bova joined the Department of Radiation Oncology at the University of Florida. He was promoted to Associate Professor in Radiation Oncology in 1989. In 1991 he was appointed as the Einstein Fund Professor of Computer-Assisted Stereotactic Neurosurgery within the Department of Neurosurgery. In 1994 he was promoted to Professor of Radiation Oncology. In January of 1999 he joined the faculty of Neurosurgery at the University of Florida and was appointed Professor of Neurosurgery.

Since 1979 Dr. Bova has been a member of the Graduate research Faculty at the University of Florida and was appointed to the Doctoral Research faculty in 1987. He holds appointments in the Departments of Nuclear and Radiological Sciences and the Department of Neuroscience. In 1990 Dr. Bova and Dr. William Friedman received the University of Florida College of Medicine's Faculty Research Prize in Clinical Science for their work in the development of the University of Florida's Stereotactic Radiosurgery system. Their work has resulted in 5 patents dealing with both mechanical and computer system associated with radiosurgery and image guided procedures.

Dr. Bova has been very active in the Florida Chapter of the American Association of Physicist in Medicine, holding the office of President for 1997-8. He had previously served as the President of the Southeast Chapter of the AAPM from 1985-86. He is also active in the American Association of Physicist in Medicine serving as a Board member in 1998-2000. He is also a Board member of the International Society of Radiosurgery. Dr. Bova has served on committees for the State of Florida's Department of Radiation Control, the American Cancer Society, American College of Radiology, the Florida Radiological Society, the American Society of Therapeutic Oncologist, the American Association of Physicist in Medicine. He has also serves as a Delegate to the International Electrotechnical Commission. He has been active in the American Board of Radiology, chairing the Physics section of the written examination for Therapeutic Oncologist since 1994.

In 1985 Dr. Bova and Dr. William Friedman began a collaborative project that was responsible for establishing the University of Florida's radiosurgery program. Since its inception this program had treated over 1300 radiosurgery patients and 0ver 200 stereotactic radiotherapy patients. Over 80 papers and chapters as well as numerous presentations at national and international meeting. In 1998 the Radiosurgery/Biology Laboratory at the University of Florida Brain Institute was established. Dr. Bova along with Dr. Friedman and Dr. Dietmar Siemann are co-directors of this facility.

Frank J. Bova, Ph.D. and William A. Friedman, M.D.