Sterotactic radiosurgery is a form of:

Ans: A (Radiotherapy) Ref: Devita's Cancer: Principles and Practice of Oncology, 7th edition, pg: 283Explanation:Stereotactic RadiosurgeryIt is a type of external beam radiation therapy.It is a single day procedure for treating small intracranial lesion.The technique requires metallic frame that is rigidly attached to the patient head.The patient undergoes CT scan and three dimensional treatment planning is performed.A number of small beams are designed to create a highly conformational treatment plan.The beam delivered has accuracy in millimeters due to the sterotactic ring.Treatment is delivered as a single beam fraction (15 to 20 Gy).Major limitation is that it can be used for small tumors only.It uses special equipment to position the patient and precisely deliver radiation to a tumor.The total dose of radiation is divided into several smaller doses given over several days.Used to treat brain tumors and other brain disorders.It is also being studied in the treatment of other types of cancer, such as lung cancer.