The Gamma Knife® and Gamma Knife radiosurgery are considered by many to be the “gold standards” of stereotactic radiosurgery for brain lesions, providing results comparable to or better than conventional surgery in many cases, without the need for a surgical incision or protracted recovery in hospital.
Cleveland Clinic Neurosurgeons and Radiation Oncologists were the first to bring stereotactic radiosurgery to Ohio in August of 1989 using a modified linear accelerator. Their extensive experience in over 400 radiosurgery cases at Cleveland Clinic led them to conclude that the benefits of stereotactic radiosurgery would be available to more patients by offering Gamma Knife radiosurgery as an alternative or, in some cases as an adjunct, to conventional neurosurgical procedures. In its first year the Program treated 214 cases, making this the most successful first-year Gamma Knife Center in North America at that time. Our Gamma Knife Center is also one of only a handful of training centers world-wide certified by the manufacturer of the Gamma Knife for training of professionals for Gamma Knife radiosurgery procedures.
In July 2007, we were the second Center in the country to upgrade our equipment to the most technologically advanced model available, Leksell Gamma Knife® Perfexion™, which allows treatment in a wider range of anatomical structures, improves treatment planning, increases patient comfort and reduces treatment time. The new equipment, uses all image modalities, including PET, CT and MRI, as well as reduced treatment time. In 2014 more than 480 Gamma Knife procedures were performed.
The Novalis unit further increases the capabilities within radiation oncology and allows for radiosurgery and fractionated radiosurgery treatments for neuro-oncology patients using image guidance. This technology gives us the ability to treat lesions near critical structures, such as the optic nerves and chiasm, as well as retreat some patients who have undergone conventional radiotherapy. In general, the Gamma Knife is used for single treatments of focused radiation that conforms to the shape of small tumors or lesions, while the Novalis delivers fractionated conformal treatment for larger malignant or benign tumors.
For more information download our Gamma Knife Treatment Guide.
How Does Gamma Knife Work?
For Gamma Knife radiosurgery, a single one- to two-hour treatment is typically required, in which 192 beams of gamma rays are focused at multiple points throughout the target with the aim of matching the delivered radiation to the shape of the tumor.
Thus, the gamma radiation is concentrated in the tumor, and falloff in adjacent tissue is very steep, minimizing radiation to tissue lying in the entry or exit pathways. Because of this precise focusing ability, aggressive, high-dose gamma radiation can be delivered to stabilize, shrink, or destroy some lesions – even those deep in the cerebral hemispheres or brain stem.
The most common indication for Gamma Knife radiosurgery procedure is brain metastases, a condition that afflicts nearly a quarter of patients suffering from cancer. For the past several years, the most common indication of all Gamma Knife radiosurgery treatments at our center was for metastatic disease. The remaining percentage of Gamma Knife radiosurgery treatments were for primary and benign tumors, trigeminal neuralgia and arteriovenous malformations.