Abstract
Renal scintigraphy complemented with sonography plays an important role in the management of renal transplant patients. When performing a renal sonogram shortly after the completion of a renal scan, the sonographer is exposed to potentially significant levels of radiation originating from the patient. To quantify this, we measured exposure rates up to 28 hrs postinjection in 5 renal transplant patients who underwent 6 studies with 20 mCi of technetium-99m DTPA. Whole body and hand exposure rates were 4.9 and 19.8 mR/hr, respectively. Since the radiation exposure of the sonographer who performs the study is significant, a table is provided for use as a guide for the maximum number of patients that could be studied and the maximum number of examination hr that can be accrued before the annual limits recommended by the National Council on Radiation Protection are exceeded. Recommendations are given to reduce the exposure to as low as reasonably achievable.