Final answer:
A collimator such as an Anger camera or gamma camera is used in technetium SPECT to produce images by collimating gamma rays and enabling the construction of a three-dimensional visualization of a radiopharmaceutical compound in the body.
Step-by-step explanation:
The collimator used for technetium SPECT is designed to facilitate single-photon-emission computed tomography (SPECT), which is an advanced imaging technique. In the context of radiopharmaceuticals such as technetium-99m (Tc-99m), a specific type of collimator, like an Anger camera or gamma camera is typically employed.
This camera uses a piece of lead with holes to collimate gamma rays emerging from the patient, directing them towards detectors that can only receive gamma rays from specific directions. The resulting data are then used by a computer to create an image, often producing three-dimensional visualizations of the concentration of the radiopharmaceutical compound. While the spatial resolution of SPECT may be relatively low (around 1 cm), it provides good contrast making images clear and distinguishing different tissues.