Abstract: A nuclear radiation attenuator for providing a test image from a source of radiation is disclosed. The attenuator provides a test image including a plurality of discrete target images located in a background image. Each target image has an intensity that differs from the intensity background image to provide a target to background contrast ratio for each target image. A plurality of the target images each have a different contrast ratio so that the contrast ratios of the target simulate contrast ratios found in clinical testing. The attenuator provides a standardized test image that enables the performance of a scintillation camera to be tested routinely.

Abstract: A radiation protective device for use in the injection of a bolus of radioactive material into a blood vessel is described. A bolus retainer is used having a bolus chamber sized to retain a desired bolus size. The chamber extends between front and rear ends of the bolus retainer which fits within a radiation shield. The front end is adapted to be connected to a hypodermic needle. The rear end is adapted for connection to a first syringe sized to precisely draw in the desired bolus size and a flushing syringe to advance the bolus into a blood vessel through the hypodermic needle. The bolus retainer has a valve located near its rear end to retain the bolus in the chamber when the flushing syringe is inserted to replace the first syringe. An improved technique for administering a radioactive bolus is described with substantially less radiation exposure and improved control and speed over the bolus injection.