Storage telemetric system for detection of radionuclide tracers in humans

An external-storage telemetric device for continuous detection and registration of radionuclide tracers in humans is described. The weight of the system is 600 g. A pocket-sized ECG cassette tape recorder with 24-h continuous registration constitutes the storage unit. Two end-window GM detectors (Philips 18515) are used as surface detectors. Both gamma- and beta-emitters are detected by this equipment. The linear range is 100 counts/s. Renal excretion of [125I]iodide during 30 h in a normal person is shown. The disappearance rates are 0.1 h-1 during the day and 0.05 h-1 during the night. The coefficient of variation of the individual slopes has been calculated to less than 5%. A comparison with the analog radiotelemetric equipment is shown. The storage telemetric equipment can be applied outside the hospital, when the patient is ambulatory.