Lung Scan - renal uptake

Clinical history: 85 y-male arrived in nuclear department for a lung scan to rule out pulmonary embolism.

Technique: Patient received 20 mCi Xe133 ventilation, followed by 30 mCi Tc99m MAA for lung perfusion imaging.

There was renal uptake noted on the perfusion images which was an unexpected finding. Following investigation it was found that the patient had come into the medical center the previous night through the emergency room and a lung scan had been started. Due to equipment malfunction the perfusion portion of the scan was not completed, and was to be repeated the following morning. The uptake by the kidneys was determined to be most likely due to biological breakdown of the Tc99 MAA from the previous night, which was being removed from the body through the kidneys.
Thanks to Cheryl Casale, 2004.