• IMRT
• IGRT
• Respiratory Gating
• Radiosurgery

Intensity-modulated radiation therapy (IMRT) is an advanced form of three-dimensional conformal radiotherapy (3DCRT). Sophisticated software and hardware are used to modulate the intensity of radiation beam that allows delivery of a higher radiation dose to the tumor while minimizing radiation exposure to surrounding normal tissues. With IMRT, the radiation is effectively broken up into thousands of tiny pencil-thin radiation beams whose intensity can each individually be modulated. These beams are targeted at the tumor from many different angles. The net effect is that radiation dose can be “wrapped” around tumors far more precisely than was previously possible.

Currently, IMRT can be used to treat select patients with prostate, head and neck, breast, brain, pancreas, lung, thyroid, liver, gynecologic and other various types of cancers. Using IMRT, higher and more effective radiation doses can safely be delivered to tumors with fewer side effects compared with conventional radiotherapy techniques. IMRT can also be used to retreat cancers that have previously been irradiated, and safely treat tumors that are located very close to delicate organs that may lie close to the tumor. As a result, higher cancer control rate and a lower rate of side effects are possible.

Image-guided radiation therapy (IGRT) is an advanced technology that allows radiation to be delivered to tumors with more precision than was traditionally possible. IGRT can be accomplished either using ultrasound or x-ray based technology along with sophisticated computer software to deliver unprecedented targeting and localization of tumors on a daily basis. Any daily variations in body and internal organ movement are taken into account before treatment. This dramatically reduces the need for large target margins that have traditionally been used to compensate for errors in localization.

Prior to IGRT, radiation oncologists compensated for the day to day variations in the position of a tumor due to changes in patient positioning, internal organ motion and respiratory motion, by treating by treating a larger volume. With IGRT, these day to day variations are accounted for prior to treatment. Thus, treatment volumes can be reduced thereby sparing greater amounts of normal, healthy tissue exposed to radiation while still maximizing dosage to the tumor. This results in better tumor control with fewer side effects and complications.

IGRT can be used in conjunction with conventional therapy, three-dimensional conformal radiotherapy (3DCRT), and IMRT to improve the daily targeting of virtually any type of cancer treatable by radiation therapy.

Respiratory gating is new technology that synchronizes radiation treatment to a patient's breathing pattern. In certain locations in the body such as the lungs or the abdomen, the tumor can move up to 2 inches during respiration. In the past, this movement was compensated for by creating intentionally large treatment volumes that would hopefully ensure full coverage of the tumor during the entire breathing cycle. Unfortunately, this resulted in increased exposure of normal, healthy tissue to radiation.

With respiratory gating, the radiation beam is continuously turned on and off in synchrony with the respiratory cycle. The radiation is delivered only when the tumor is within the treatment field. Smaller beams can be used, thus reducing the damage to surrounding normal, healthy tissue that would otherwise receive radiation using conventional treatment methods. Respiratory gating can be used in combination with three dimensional conformal therapy or IMRT and is most useful in the treatment of tumors in lungs or upper abdomen.

Radiosurgery may be used as a non-invasive alternative to standard surgical operations or as an adjunctive therapy in the treatment of residual or recurrent lesions left unresected by conventional surgery. Radiosurgery can be especially useful for those patients who are not suitable for standard surgical techniques due to illness or advanced age. In many cases, radiosurgery is the only feasible treatment option available. This treatment is usually given on an outpatient basis in one to five sessions.

There are several existing types of radiosurgical systems available. Some are only able to treat intracranial disease while others are capable of treating all body sites. What all systems have in common is that they are capable of delivering highly accurate treatment. Using a multitude of collimated beams of ionizing radiation in scalpel like precision, treatment can be given with very little damage to the healthy surrounding tissues.

Currently, radiosurgery has a well established treatment record for intracranial tumors such as glial tumors, acoustic neuromas, pituitary adenomas, meningiomas, chordomas, metastases, arteriovenous malformations and brain dysfunctions like trigeminal neuralgia. There is a growing body of experience showing utility of radiosurgery for extracranial tumors of the lung, spine, pancreas, liver, pancreas, prostate, kidney, and head & neck.