Multileaf Collimators (MLC) consist of (currently 20-100) pairs of movable metal leaves which are used to block radiation in Intensity Modulated Radiation Therapy (IMRT). The leaves modulate a uniform source of radiation to achieve given intensity profiles. The modulation process is modeled by the decomposition of a given non-negative integer matrix into a non-negative linear combination of mat...

Conceptually, a typical spectroscopic experiment is extremely simple. Electromagnetic radiation at a certain nominal wavelength λ is allowed to impinge on the sample. Then some properties of the radiation that emerges from the sample are measured. One of the simplest properties is the fraction of the incident radiation absorbed or dissipated by the sample. (Typical techniques are optical absorp...

We report the case of a 41-year-old man with a late recurrence of nonseminomatous germ cell tumor, which was successfully treated with intensity-modulated radiation therapy. For the residual retrocrural tumor invading the 11th and 12th thoracic vertebrae with an abnormal level of tumor marker (α-fetoprotein: 23.2 ng/ml) after salvage chemotherapy, chemotherapy could not be continued due to its ...

BACKGROUND Radiation therapy (RT) of bone metastases provides an important treatment approach in palliative care treatment concepts. As a consequence of treatment, the extent of radiation-induced toxicity is a crucial feature with consequences to a patient's quality of life. In this context this study aims at reducing the extent of radiation-induced side effects and toxicity by assuming a bette...

Radiation therapy is a non-invasive treatment modality for cancer patients. Radiation therapy treatment planning for cancer patients provides many challenging optimization problems. Various variables of a treatment plan need to be optimized so that the resulting plan can kill all cancerous cells while minimizing damage on the patient’s normal tissues. Intensity modulated proton therapy (IMPT) h...

Cancer is the second leading cause of death behind heart disease in the United States (National Center for Health Statistics, 2006). Various caner treatments are available now, but the three most common types are surgery, chemotherapy, and radiotherapy. Radiotherapy uses radiation—in the form of a special kind of x-rays, γ-rays, electrons, or protons to kill cancer cells. The advance of modern ...