Radiation-induced lung injuryAutomatic exposure control: Automatic Exposure Control (AEC) is an X-ray exposure termination device. A medical radiography x-ray exposure is always initiated by a human operator.External beam radiotherapyHypersensitivity pneumonitis: A multinucleated giant cell, seen within the interstitium to the right of the picture halfway down, is an important clue to the correct diagnosis.|Targeted therapy of lung cancer: Targeted therapy of lung cancer refers to using agents specifically designed to selectively target molecular pathways responsible for, or that substantially drive, the malignant phenotype of lung cancer cells, and as a consequence of this (relative) selectivity, cause fewer toxic effects on normal cells.Philip D'Arcy HartPemetrexedHospital-acquired pneumonia: Hospital-acquired pneumonia (HAP) or nosocomial pneumonia refers to any pneumonia contracted by a patient in a hospital at least 48–72 hours after being admitted. It is thus distinguished from community-acquired pneumonia.Lung receptor: Lung receptors sense irritation or inflammation in the bronchi and alveoli.Radiosurgery: Radiosurgery is surgery using radiation, that is, the destruction of precisely selected areas of tissue using ionizing radiation rather than excision with a blade. Like other forms of radiation therapy, it is usually used to treat cancer.Megavoltage X-raysAbscopal effect: The abscopal effect is a phenomenon in the treatment of metastatic cancer where localized treatment of a tumor causes not only a shrinking of the treated tumor but also a shrinking of tumors in different compartments from the treated tumor. Initially associated with single-tumor, localized radiation therapy, the term has also come to encompass other types of localized treatments such as electroporation and intra-tumoral injection of therapeutics.Dense artery sign: In medicine, the dense artery sign or hyperdense artery sign is a radiologic sign seen on computer tomography (CT) scans suggestive of early ischemic stroke. In earlier studies of medical imaging in patients with strokes, it was the earliest sign of ischemic stroke in a significant minority of cases.Non-specific interstitial pneumonia: Non-specific interstitial pneumonia (NSIP) is a form of idiopathic interstitial pneumonia.Radiation protection of patients: Patients are exposed to ionizing radiations when they undergo diagnostic examinations using x-rays or radiopharmaceuticals, therapy of cancer or benign lesions using radiations emitted by radioisotopes or those by radiation generators; and in interventional procedures using fluoroscopy. There has been a tremendous increase in the use of ionizing radiation in medicine during recent decades.Low-dose chemotherapy: Low-dose chemotherapy is being studied/used in the treatment of cancer to avoid the side effects of conventional chemotherapy. Historically, oncologists have used the highest possible dose that the body can tolerate in order to kill as many cancer cells as possible.