Abstract: Portal localization radiographic elements and a process of confirming the targeting of a beam of X-radiation of from 4 to 25 MVp using the portal radiographic elements are disclosed. The X-radiation is directed at a subject containing features that are identifiable by differing levels of X-radiation absorption. After a first X-radiation exposure a shield containing a portal is placed between the subject and the source of X-radiation. X-radiation is directed at the subject through the portal. In each instance the X-radiation leaving the subject impinges on a metal screen, causing it to emit electrons, and the electrons impinge upon a fluorescent screen, causing it to emit light, creating during the first and second exposures first and second superimposed latent images in the radiographic element.

Abstract: Portal radiographic elements and a process of confirming the targeting of a beam of X-radiation of from 4 to 25 MVp using the portal radiographic elements are disclosed. The X-radiation is directed at a shield containing a port to create a beam. The beam is directed at a selected anatomical feature of a patient over a period of at least 30 seconds. The portion of the beam that passes through the patient impinges on a metal screen, causing it to emit electrons, and the electrons impinge upon a fluorescent screen, causing it to emit light that exposes a portal verification radiographic element to create a latent image in light-sensitized silver halide grains. A processor is employed to convert the latent image to a viewable silver image from which intended targeting of the X-radiation beam can be verified.

Abstract: The problem of sensing the presence of radiographic elements using infrared sensors that occurs when a radiographic element contains one or more very thin tabular grain emulsions a total silver coating coverage of less than 30 mg/dm.sup.2 is addressed by placing particles in one or more non-emulsion hydrophilic colloid layers. The particles are removable during rapid access processing, have a mean equivalent circular diameter of from 0.3 to 1.1 .mu.m, and have an index of refraction at the wavelength of the infrared radiation that differs from the index of refraction of the hydrophilic colloid by at least 0.2.

Abstract: An element capable of forming a silver image is disclosed containing insufficient radiation-sensitive silver halide grains to render the element detectable by an infrared sensor. The element has been modified to increase infrared specular density by the inclusion of, in a hydrophilic colloid dispersing medium, particles (a) being removable from the element during a rapid access processing cycle, (b) having a mean size of from 0.3 to 1.1 .mu.m and at least 0.1 .mu.m larger than the mean grain size of the radiation-sensitive grains, and (c) having an index of refraction at the wavelength of the infrared radiation that differs from the index of refraction of the hydrophilic colloid by at least 0.2.