We have gathered together the latest in cancer diagnostic and treatment technology. From tried and true devices like MRI and CT to the latest innovations like CyberKnife and TomoTherapy, our doctors and technicians have unprecedented views of the human body to accurately and efficiently treat cancer.
Intensity-Modulated Radiation Therapy (IMRT)
Intensity-modulated radiation therapy (IMRT) is an advanced mode of high-precision radiotherapy that utilizes computer-controlled x-ray accelerators to deliver precise radiation doses to a malignant tumor or specific areas within a tumor. The radiation dose is designed to conform to the three-dimensional (3-D) shape of the tumor by modulating or controlling the intensity of the radiation beam to focus a higher radiation dose to the tumor while minimizing radiation exposure to surrounding tissues. Treatment is carefully planned by using 3-D computed tomography (CT) images of the patient in conjunction with computerized dose calculations to determine the dose intensity pattern that will best conform to the tumor shape.
Because the ratio of normal tissue dose to tumor dose is reduced to a minimum with the IMRT approach, higher and more effective radiation doses can safely be delivered to tumors with fewer side effects when compared with conventional radiotherapy techniques. IMRT also has the potential to reduce treatment toxicity.
Image Guided Radio Therapy (IGRT)
Image Guided Radio Therapy (IGRT) takes the advantages of Intensity-modulated radiation therapy (IMRT) to help target cancerous tumors. Today’s high end radiosurgery techniques enlist the use of Tomotherapy and Cyberknife.
TomoTherapy uses a CT scanner to provide a three-dimensional (3D) image that ensures accurate and efficient treatment for every cancer patient every time. This consistency aids the helical (continuous 360º) IMRT to accurately aim tens of thousands of narrow beamlets, all targeting the tumor and individually-optimized to contribute to the total tumor dose. This extreme accuracy translates to the most precise conformal radiotherapy available. Cancers that can be treated with TomoTherapy include:
- Bone Mets
- Head and neck
- Spinal Cord
Gamma Knife Stereotactic Radiosurgery has been used in the United States for over 10 years, with 300,000 procedures having been performed worldwide. The most common diseases treatable with this procedure would be brain mets, AVMs and perhaps trigeminal neuralgia.
For a complete discussion of Gamma Knife radiosurgery, click here.
CyberKnife Stereotactic Radiosurgery is a medical procedure that utilizes very accurately targeted doses of radiation to precisely treat cancer. This noninvasive “operation” has proven to be an effective alternative to surgery or conventional radiation for treating many small tumors.
In contrast to the standard frame-based radiosurgical instruments, the CyberKnife uses noninvasive image-guided localization and a robotic delivery system. This combination of technologies enables the CyberKnife to overcome the limitations of older frame-based radiosurgery.
The CyberKnife belongs to a new class of radiotherapy techniques called IGRT (image-guided radiotherapy). The CyberKnife is unique in that it uses a compact linear accelerator (LINAC) mounted on an image-guided robotic arm to deliver multiple beams of high energy x-rays to a target. The ability of the CyberKnife to shape the profile of radiation to conform to the patient’s individual anatomy allows for maximum sparing of surrounding normal tissues. The CyberKnife accomplishes this by accurately cross-firing approximately 150 beams of radiation at the target from multiple directions. The CyberKnife technology represents an improvement upon the most advanced conventional radiation therapy techniques. Similar to Intensity Modulated Radiotherap (IMRT), CyberKnife can produce a highly conformal dose distribution that “matches” the shape of treatment area and spares adjacent tissue.
Conditions treated with CyberKnife include:
High Dose Rate (HDR) Brachytherapy
Brachytherapy is a form of radiation where the radioactive source is brought close to the target tissue rather than treating it from a distance with a machine (called external beam irradiation).
Common types of brachytherapy include implanting radioactive seeds into a tumor. These seeds are left in permanently and give off radiation in a slow manner (called low dose rate radiation). Other techniques include implanting tubes of radium or cesium that will slowly radiate a tumor over a matter of hours.
New devices use highly radioactive isotopes that will treat a tumor in a matter of minutes and are referred to as high dose rate (HDR) devices. These devices have been used to treat gynecologic, lung and esophagus cancers.
More recently HDR techniques have been used to treat breast cancer, reducing a six-week course down to five days.
Prostate seeds are small radioactive devices that are placed strategically around the prostate. These seeds give off radiation in a slow manner (called low dose rate radiation) to target cancer without effecting nearby organs.
Digital Mammography & Ultrasound
There is now general agreement that screening mammography reduces the rate of death from breast cancer among women who are 40 years of age or older. The overall diagnostic accuracy of digital and film mammography as a means of screening for breast cancer is similar, but digital mammography is more accurate in women under the age of 50 years, women with radiographically dense breasts and premenopausal or perimenopausal women.
Computer Tomography (CT)
Computed tomography (CT) is a medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. WellSpring has the latest advancement in CT with High Resolution CT, a more accurate and detailed image allowing our doctors more information.
Position Emission Tomography (PET)
Positron emission tomography (PET) is a nuclear medical imaging technique that produces a three-dimensional (3D) image or map of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radioisotope, which is introduced into the body on a metabolically active molecule. Images of metabolic activity in space are then reconstructed by computer analysis, often in modern scanners aided by results from a CT X-ray scan performed on the patient at the same time, in the same machine.
Magnetic Resonance Imaging (MRI)
Magnetic resonance imaging (MRI) is primarily used in medical imaging to visualize the structure and function of the body. It provides detailed images of the body in any plane. MRI has much greater soft tissue contrast than Computed Tomography (CT) making it especially useful in neurological, musculoskeletal, cardiovascular and oncological diseases. Unlike CT, it uses no ionizing radiation. The scanner creates a powerful magnetic field which aligns the magnetization of hydrogen atoms in the body. Radio waves are used to alter the alignment of this magnetization. This causes the hydrogen atoms to emit a weak radio signal which is amplified by the scanner. This signal can be manipulated by additional magnetic fields to build up enough information to reconstruct an image of the body.
The different imaging technologies each provide different types of information. The CT scan may show the bones the best and have the least geometric distortion but the MRI may give much better soft tissue definition and the PET scan may be the most reliable in separating cancer tissue from normal tissue. Often, the most accurate way to target the cancer and avoid the normal tissue is to scan the patient in the actual treatment position using several different techniques (CT, MRI or PET) and then fuse the images on the treatment planning computer, so that all the information is being used to best target the cancer. This process is called image fusion. It is most reliable when the imaging devices have been equipped with the same type of laser targeting equipment that is mounted on the radiation treatment machines.
Florida Cancer Treatment Facility
WellSpring is a Complete Cancer Care facility that's easily accessible from St Petersburg, Clearwater, Largo or anywhere in the Tampa Bay Area of Florida. Contact the cancer experts at WellSpring if you have questions about cancer risk, cancer prevention or cancer screening.