Treatment Modalities: IGRT

What is IGRT?

IGRT is a radiation treatment technique known as Image Guided Radiation Therapy. It describes the general procedure of using various imaging methods to improve the treatment accuracy by realigning a patient’s setup on a daily basis, just before the delivery of the therapeutic radiation.

Why is IGRT important?

Radiation treatment is planned and delivered using high intensity levels of radiation that specifically target the site of disease and spare as much of the surrounding normal tissue as possible. However, delivering the planned treatment accurately is a significant challenge due to organ motion, deformation, and uncertainties in repeating and maintaining the set-up of the patient. Failure to do so could result in a geographical miss of the targeted disease, or over-treatment of nearby critical structures. Therefore, the ability to reproduce a patient’s setup on a daily basis is essential to each and every treatment. Traditional and standard methods used to check a patient’s setup use X-ray films to align bony anatomy once a week. This method does not have the ability to show internal soft tissue such as tumor sites and organ locations, nor does it tell us anything about what is happening on the other treatment days. Due to the limitations of this technique, larger treatment fields are required to account for any organ movement that occurs during the course of a patient’s treatment. IGRT alleviates the need for these larger fields by revealing the location of detailed soft tissue anatomy each day before a patient’s treatment. This technique ensures accurate targeting of the disease, which then allows for smaller, more precise treatment fields that conform to the shape of a tumor, and therefore greatly reduces the patient’s risk of incurring side effects.

IGRT at Morristown Medical Center

Our IGRT technique uses a machine with a combined in-room diagnostic CAT scanner and Linear Accelerator (commonly known in the industry as a “CT on rails”), which uses high resolution images that reveal detailed internal anatomy of the patient. These images are then used to target the exact location of the patient’s disease with millimeter accuracy seconds before each treatment. This enables the potential to minimize side effects of radiation therapy by reducing the margins previously set to account for uncertainties of target dimensions/location/movement. The Radiation Oncology Department at Morristown Medical Center was the first institution to implement this kind of IGRT treatment in the United Sates and have been treating patients with this technique since the year 2000. Our innovative IGRT process and extensive years of experience offer the most accurate radiation treatment available with a superior imaging modality that is unmatched in the field of radiation oncology.