Purpose: In scintigraphy of the sentinel lymph node, it is common to use a lead plate as a shield to reduce star artifact and scattered radiation in the portion surrounding the injected site of radioactive colloid. We have developed an imaging method without using a lead plate, and examined its usefulness in phantom and clinical imagings.
Methods, results: Star artifact was eliminated using a medium energy collimator. Effects of scattered radiation from the injection site were reduced by setting energy window at higher level.
Conclusions: Our method without using a lead plate can be applied to dynamic data acquisition and imaging of a portion where it is difficult to place a lead plate. It also seems to be a useful imaging method in that it takes patients' feelings into consideration.