Kinetics and dosimetry of thallium-201 in human testes.
Thallous chloride (201Tl) is a well-known imaging agent. It has been shown to accumulate in the testes. In view of this, the testicular kinetics of 201Tl is investigated in humans and the absorbed dose to the organ calculated.


METHODS
Thallous chloride 201Tl was injected intravenously into four patients for myocardial perfusion studies. After clinical evaluation, the testicular uptake and clearance of 201Tl were monitored for about 1 wk using a gamma camera.


RESULTS
Testicular uptake of 201Tl was rapid with a mean biological uptake half-time of 0.67 hr and mean biological clearance half-time of 280 hr. The mean maximum testicular uptake of 201Tl was about 0.4% of the injected activity. These data were utilized to calculate the average absorbed dose to the testes. The absorbed dose to the testes was calculated to be 3.5 x 10(-4) Gy/MBq (1.3 rad/mCi) of injected activity.


CONCLUSIONS
When the relative biological effectiveness of the Auger emitter 201Tl is taken into account, the equivalent dose to the testes is 9.5 x 10(-4) Sv/MBq (3.5 rem/mCi).
Rao
D V
DV
Department of Radiology, New Jersey Medical School, Newark 07103, USA.
Shepstone
B J
BJ
Wilkins
H B
HB
Howell
R W
RW
D000328:Adult; D006207:Half-Life; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D011835:Radiation Protection; D011874:Radiometry; D011877:Radionuclide Imaging; D013737:Testis / Q000528:radiation effects*; D013794:Thallium Radioisotopes / Q000493:pharmacokinetics; D013997:Time Factors
D013794:Thallium Radioisotopes