Search results
Results from the WOW.Com Content Network
Superficial and orthovoltage X-rays have application for the treatment of cancers at or close to the skin surface. [2] Typically, higher-energy megavoltage X-rays are chosen when it is desirable to maximize "skin-sparing" (since the relative dose to the skin is lower for such high-energy beams).
Megavolt X-ray (or photon) therapy, which delivered a beam of 25 MeV X-ray photons. The X-ray photons are produced by colliding a high current, narrow beam of electrons with a tungsten target. The X-rays are then passed through a flattening filter, and then measured using an X-ray ion chamber. The flattening filter resembles an inverted ice ...
Doctor reviewing a radiation treatment plan. In radiotherapy, radiation treatment planning (RTP) is the process in which a team consisting of radiation oncologists, radiation therapist, medical physicists and medical dosimetrists plan the appropriate external beam radiotherapy or internal brachytherapy treatment technique for a patient with cancer.
The purpose of the ink marks was to align and position the patient daily for treatment to improve reproducibility of field placement. By aligning the markings with the radiation field (or its representation) in the radiation therapy treatment room, the correct placement of the treatment field could be identified. [8]
Medicine has used radiation therapy as a treatment for cancer for more than 100 years, with its earliest roots traced from the discovery of X-rays in 1895 by Wilhelm Röntgen. [119] Emil Grubbe of Chicago was possibly the first American physician to use X-rays to treat cancer, beginning in 1896. [120]
Due to the higher ionization density caused by soft X-ray radiation in the tissue, the relative biological effectiveness (RBE) of low-energy X-rays on tumor cells is higher when compared to high-energy X-rays or gamma rays which are delivered by linear accelerators. [15]
The device consists of a small linear accelerator attached to a robotic arm, along with an integrated image guidance system. During treatment, the image guidance system captures 3D images, tracks the movement of tumors, and guides the robotic arm to accurately aim the treatment beam at the moving tumor. [2]
Orthovoltage X-rays are produced by X-ray tubes operating at voltages in the 100–500 kV range, and therefore the X-rays have a peak energy in the 100–500 keV range. [1] Orthovoltage X-rays are sometimes termed "deep" X-rays (DXR). [ 2 ]