Conformal 3D Radiotherapy

Conformal 3D Radiotherapy (3D-CRT) leverages the anatomical visualization capabilities of CT (Computed Tomography) or MR (Magnetic Resonance) imaging to treat the tumor based on its volumetric or three-dimensional shape. These three-dimensional images facilitate the identification of normal organs that we do not want to irradiate and the tumor that we intend to irradiate in its entirety. By visualizing all these structures in a three-dimensional form, the radiation oncologist, working in conjunction with the Medical Technologist and the Medical Physicist, carefully determine the optimal radiation configuration.

The term “conformation” is applied when, aided by the three-dimensional image, the multileaf collimator leaves are molded and adapted according to the projected shape of the tumor in that particular position, taking into account the gantry angle (or arm of the Linear Accelerator) and the position of the treatment couch. The three-dimensional conformation of the dose is achieved by combining beams that enter from different planes and converge at the isocenter, allowing the dose distribution to conform to the shape of the tumor. Hence the name 3D conformal radiotherapy (3D-CRT). Another advantage that comes with the use of three-dimensional images and Radiotherapy planning systems is that they produce graphs known as dose-volume histograms. These graphs enable the quantitative assessment of the dose delivered and to which volume, whether it be the tumor or the involved organ at risk. In this way, our specialists can ensure that the dose administered to the tumor will not lead to subsequent complications.