In this blog post, we explore whether Gamma Knife surgery could be a non-invasive innovation in treating brain tumors without opening the skull.
Brain tumors are rare diseases that account for only 0.9% of all cancers, referring to all tumors that develop inside the skull. However, the primary treatment for brain tumors, surgical resection, involves opening the skull and removing part of the brain, which can be highly invasive and burdensome for patients. As a result, Gamma Knife surgery, a type of radiation surgery that uses radiation to destroy tumor cells, has gained significant attention in recent years.
Radiation surgery is a treatment method that focuses radiation on the target tumor cells to remove the tumor. To better understand this, imagine stage lighting. Light from a single source is weak, but when multiple lights are combined, a very bright light shines on the center of the stage. Similarly, radiation from a single source is weak and has little effect on normal cells. However, when radiation from multiple directions converges at a single point, its intensity becomes strong enough to destroy the targeted tumor cells. Radiation therapy, which uses radiation to remove tumors, has been used for a long time, but it differs from radiation surgery in that it exposes a wide area to radiation without distinguishing between normal cells and tumor cells.
Gamma Knife surgery is a type of radiation surgery that uses gamma rays emitted from cobalt-60 isotopes to treat brain tumors. The Gamma Knife consists of a cobalt-60 source arranged in a hemispherical shape around the head, emitting gamma rays from over 200 different directions to form a focal point at the center. By positioning the tumor at this focal point, tumor cells are destroyed. This process allows for the removal of tumors without opening the skull, minimizing damage to normal cells.
Gamma Knife surgery requires accurate identification of the tumor’s location, followed by determining the range and intensity of radiation to be administered. First, a stereotactic frame is attached to the patient’s head, and MRI, CT, and angiography are used to analyze the tumor’s location in three dimensions. The stereotactic frame fixes the patient’s head in place during surgery to prevent movement and must be maintained throughout the procedure.
The images obtained are reconstructed in three dimensions, and the doctor uses them to determine the radiation dose and intensity while considering important tissues such as the optic nerves surrounding the tumor. The surgery is performed by exposing the patient, who is lying on the operating table, to a predetermined amount of radiation according to the planned coordinates. There is no pain or noise during the procedure, and the patient can move their body freely except for their head.
The surgery can take anywhere from 30 minutes to several hours, depending on the size and shape of the tumor. After the surgery, the stereotactic frame is removed, and the patient is stabilized before being discharged.
Radiation surgery has several clear differences from traditional surgical procedures. Surgical procedures directly remove the tumor, so immediate results can be expected, but there is a high risk associated with opening the brain and cutting tissue. In contrast, radiosurgery removes tumors using a non-invasive method, so there is almost no risk of bleeding or infection. However, while surgical procedures can remove tumors in a single session, radiosurgery requires patients to observe the results over several months as the tumor shrinks gradually, which may require patience on the part of the patient.
Gamma Knife surgery is simpler than surgical procedures, reducing the burden on patients in various ways. Most importantly, there is no need to cut open the skull, so patients can undergo the procedure under local anesthesia and be discharged on the same day, minimizing economic and psychological burdens. Additionally, Gamma Knife delivers radiation precisely calculated by a computer, making it the most accurate radiation surgery currently available.
Of course, there are still areas that need improvement. The biggest limitation of Gamma Knife surgery is that the treatment area is limited to the inside of the skull. If the tumor is located below the neck, radiation surgery is difficult to perform. This is because the patient’s chest and internal organs move while breathing, making it difficult to deliver precise radiation. However, Gamma Knife manufacturers are conducting research to overcome this limitation, and it is expected that more precise radiation surgery will be possible in the future.
With future advances in medical technology, radiation surgery such as Gamma Knife is expected to become more precise and its application range wider. Currently, researchers are studying ways to use radiation surgery to treat not only tumors but also neurological disorders and cardiovascular diseases. Additionally, new imaging technologies combined with artificial intelligence may enable patient-tailored treatments. In the coming years, the accuracy of radiation surgery is expected to improve significantly, making non-invasive treatment for various conditions throughout the body—not just outside the skull—more widespread. If research on radiation surgery, including Gamma Knife, continues to advance actively, medical innovations that allow tumors to be removed without cutting the skin could become a reality.
