Final answer:
The procedure described involves swallowing a radioactive substance followed by imaging with a gamma camera, which is an application of nuclear medicine in diagnostic medical applications, similar to Positron Emission Tomography (PET scan).
Step-by-step explanation:
The type of instrumental evaluation in nuclear medicine described in the question involves the patient swallowing a measured amount of radioactive substance, after which an image is captured by a gamma camera.
This process is related to a diagnostic medical application of nuclear medicine, specifically a technique similar to Positron Emission Tomography (PET scan), although it could also be related to other diagnostic procedures that utilize radioactive isotopes. These scans utilize the properties of radioactive decay to measure physiological processes, such as absorption in the gastrointestinal tract, and the imaging provides details about the structure and function of various organs.
The amount of aspiration and residue can be specifically measured through such procedures, which is crucial for diagnosing and treating conditions related to organ function.