Intensity-Modulated Radiation Therapy (IMRT) is an advanced type of high-precision radiation that is the next generation of 3D conformal radiotherapy (3DCRT). Computer-controlled x-ray accelerators distribute precise radiation doses to malignant tumors or specific areas within the tumor. The pattern of radiation delivery is determined using highly-tailored computing applications to perform optimization and treatment simulation (Treatment Planning). The radiation dose is consistent with the 3D shape of the tumor by controlling, or modulating, the radiation beam's intensity. IMRT also improves the ability to conform the treatment volume to concave tumor shapes, for example when the tumor is wrapped around a vulnerable structure such as the spinal cord or a major organ or blood vessel. The radiation dose intensity is elevated near the gross tumor volume while radiation among the neighboring normal tissue is decreased or avoided completely. The customized radiation dose is intended to maximize tumor dose while simultaneously protecting the surrounding normal tissue. Because of this, IMRT allows for higher radiation doses to be delivered to the tumor while sparing healthy tissue as compared with conventional radiation therapy techniques (2DXRT and 3DCRT). This in turn results in better tumor targeting, lessened side effects, and improved treatment outcomes than even 3DCRT.