D. Eshima et al., TECHNETIUM-99M-SULFUR COLLOID FOR LYMPHOSCINTIGRAPHY - EFFECTS OF PREPARATION PARAMETERS, The Journal of nuclear medicine, 37(9), 1996, pp. 1575-1578
There has been a resurgence in the use of lymphoscintigraphy for the e
xternal detection of lymph nodes for metastatic melanoma and breast tu
mors. Technetium-99m-antimony trisulfide colloid was the radiopharmace
utical developed for this procedure and was found to have a narrow dis
tribution of small particles, 0.003-0.03 mu m, but it was never approv
ed by the FDA. Technetium-99m-sulfur colloid also forms particles and
this article reports on the effects different preparation parameters h
ave on its particle size distribution and stability. Methods: Four gro
ups of kits were evaluated, kits which utilized: (a) a reduced heating
protocol with a new Tc-99m-elution, (b) a reduced heating protocol wi
th an old Tc-99m-elution, (c) a prolonged heating protocol with a new
Tc-99m-elution and (d) a prolonged heating protocol with an old Tc-99m
-elution. The particle size distribution and the stability of the diff
erent Tc-99m-sulfur colloid kit preparations were evaluated over 6 hr
utilizing polycarbonate filters ranging from 0.03 to 10 mu m. Results:
In vitro studies demonstrated no significant change in the particle s
ize distribution over a 6-hr period and all Tc-99m-sulfur colloid prep
arations had a bimodal particle size distribution pattern. Importantly
, heating the kit for shorter periods of times utilizing [Tc-99m]perte
chnetate, which had a longer ingrowth of [Tc-99m]pertechnetate, produc
ed a formulation which had the largest percentage of particles smaller
than 0.03 mu m. Conclusion: In our clinical setting, Tc-99m-sulfur co
lloid prepared with the reduced heating protocol and utilizing [Tc-99m
]pertechnetate, which has the highest ingrowth of [Tc-99m]pertechnetat
e has proved to be an excellent agent for lymphoscintigraphy studies.
This preparation has demonstrated rapid movement of the particles from
the primary site to the lymph nodes in over 97% (106/109) of the pati
ents we have studied.