Stereotactic Radiosurgery (SRS)

The UCSF Radiosurgery Program, One of The Most Advanced Facilities in USA

The UCSF Department of Radiation Oncology, in conjunction with the Department of Neurosurgery, has been engaged in stereotactic irradiation for more than 20 years. Radiosurgery began at UCSF, and in northern California, with the installation of the first Gamma Knife in 1991. In 2007, the new Gamma Knife Perfexion unit was installed including an automated positioning system that is now offering even faster and more efficient treatments. Finally in 2011, the department acquired the Extend Frame that enables fractionated treatments for larger lesions or those in more sensitive locations. UCSF continues in its pioneering efforts to provide the highest levels of patient care in the field.  

Stereotactic radiosurgery involves the delivery of a dose of X-ray treatment precisely focused on a target within the brain. The Gamma Knife is a non-invasive radiosurgery system that delivers a single high dose of radiation to well defined targets in the brain. The result is an enhanced ability to control intracranial disease coupled with a reduction in the risk of side effects from radiation therapy. The Gamma Knife is commonly used for the treatment of benign and malignant brain tumors, but many patients have been treated for a variety of medical conditions since the UCSF Gamma Knife opened in September, 1991. Gamma Knife radiosurgery is an excellent choice for treatment of:

      • Brain metastases
      • Meningiomas

      • Acoustic neuromas

      • Pituitary adenomas

      • Gliomas

      • Arteriovenous malformations

      • Trigeminal neuralgia

      • Uncommon skull base tumors

      • Epilepsy

Radiosurgery has been especially helpful for the localized, highly precise treatment of brain tumors. Due to the steep fall off of the irradiation fields (isodoses) from the center of the target to be ablated, normal structures such as the brain, and other vascular and neural structures around it, are relatively spared. This is achieved through the high mechanical precision of the radiation source, and the assured reproducibility of the target. The precision in the positioning of the patient, in the calculation of dosages, and in the safety of the patient, are all extremely high.

At UCSF, we use a team approach to care for our Gamma Knife patients. The Gamma Knife team includes radiation oncologists, neurosurgeons, physicists, radiation therapists, and nurses. Gamma Knife Radiosurgery Conference is held every Thursday afternoon. Each patient being considered for Gamma Knife treatment is discussed, and follow-up scans for treated patients are reviewed to ensure quality care. We treat five to eight patients with the Gamma Knife each week. Read about the Gamma Knife FAQ. 

Our Experts

Radiation Oncologists

 Patricia Sneed, MD

Dr. Patricia (Penny) K. Sneed is a radiation oncologist with a special interest in the treatment of breast and brain cancer. She also researches new treatments for these conditions, specifically using the gamma knife. Sneed is the recipient of numerous awards, including the Fellowship in the American College of Radiology. She earned her medical degree from Stanford University and completed a residency in radiation oncology at the University of California, San Francisco. She is a Professor in Residence in the department of Radiation Oncology at UCSF.



Igor BaraniIgor Barani, MD

Dr. Igor Barani is a radiation oncologist with a particular interest in the treatment of cancer of the brain and central nervous system. He specializes in the use of radiosurgical techniques, such as the True Beam and Cyberknife, to treat adults and children with malignant and benign conditions. He's also interested in the development and implementation of new treatments for brain tumors, especially treatments that preserve brain and other neurologic function.



Shannon FoghShannon Fogh, MD

Dr. Shannon Elizabeth Fogh is a radiation oncologist who specializes in the treatment of CNS and pediatric malignancies. She specializes in the use of Gamma Knife, Cyberknife, intensity-modulated radiotherapy (IMRT) and total body irradiation (TBI) to treat a variety of malignant and benign conditions.




Jean NakamuraJean Nakamura, MD

Dr. Nakamura's research interests include investigations in radiosurgery as well as the molecular biology of malignant glioma. She is interested in examining radiotherapy conformality and its impact on tumor control and clinical outcome, particularly with respect to preservation of neurologic function. Because several radiosurgery techniques are currently used to treat central nervous system tumors, she has compared Gamma Knife radiosurgery and Intensity Modulated Radiosurgery for complex skull base lesions in order to understand the dosimetric differences between these modalities, and the implications on normal tissue function. She is extending this research line to include an analysis of Cyberknife radiosurgery plans, which may add to our understanding of the relative merits and indications for radiosurgical techniques.


Medical Physicists

 Lijun MaLijun Ma, PhD

Dr. Lijun Ma is a physicist who specializes in stereotactic radiosurgery and stereotactic body radiotherapy (SBRT). He develops complex treatment plans and supervises quality management programs for patients undergoing radiosurgery and SBRT, including treatment with the Gamma Knife. Ma has developed and implemented several procedures and protocols that improved radiosurgery and radiotherapy. His research and clinical interests include intracranial and spinal radiosurgery, SBRT, breast and prostate cancer treatments and outcome studies.



Olivier MorinOlivier Morin, MD

Dr. Olivier Morin is a physicist who specializes in medical imaging for treatment verification and advanced forms of radiosurgery, including 3-D conformal radiation therapy, intensity modulated radiation therapy (IMRT) and stereotactic (SRS) radiosurgery. He also develops treatment plans for external beam radiation and Gamma Knife. Morin's research focuses on developing and implementing image guidance tools to improve the efficiency and reduce the side effects of radiation treatment. He is also responsible for the development and clinical implementation of the modulated arc total body irradiation technique.