Clinac High Energy Medical Linear Accelerator, a Trilogy Radiotherapy Delivery System; Model #s: H14, H18, H27, H29, HCX; Product is manufactured and distributed by Varian Medical Systems Inc., Palo Alto, CA || The Trilogy Radiotherapy Delivery System is a radiation therapy accelerator intended to deliver megavoltage x-ray treatments for conventional radiotherapy (three dimensional conformal radiotherapy and intensity modulated radiotherapy) and stereotactic radiosurgery and radiotherapy. Stereotactic treatments are intended for therapy of lesions, e.g., arteriovenous malformations, primary tumors and metastases. Stereotactic treatments may be intracranial or extra cranial and consist of single-session or fractionated delivery.