The non-conventional use of 99mTc-Tetrofosmine for dynamic hepatobiliary scintigraphy

Classic dynamic hepatobiliary scintigraphy (DHBS) is commonly performed with 99mTc-Iminodiacetic Acid (IDA) derivatives and represents a non-invasive diagnosis method for biliary dyskinesia, fistulas, surgical anastomosis, etc (1). This study assesses the possibility of performing DHBS with 99mTc-Tetrofosmine (TF), a radiopharmaceutical (RF) dedicated to myocardial perfusion scintigraphy (MPS), but being excreted through the liver. The possibility to use 99mTc-TF for DHBS may be important in situations when the standardized RF for this procedure (IDA derivatives) is not available.

We performed DHBS for 30 patients referred for investigation by internal medicine and surgery departments. The patients had been fasting for 12 hours. The dynamic investigation started simultaneously with the intravenous (IV) administration of 37-110 MBq (1-3 mCi) 99mTc-TF. Dynamic images were recorded for 30-45 minutes, one image per minute, followed by static scintigraphy at 1 h, 1.5 h, 2 h, and 3 h after IV injection.

The quality of scintigraphic images of the liver and biliary tree obtained at DHBS with 99mTc-TF ensured the correct diagnosis of biliary dyskinesia, stasis, stenosis, and fistulas.

DHBS using 99mTc-TF is justified by the image quality and by the good cost/benefits ratio. Because the IDA derivatives are not always available, this finding may be important for medical practice. 99mTc-TF evacuated through the bile duct allows DHBS interpretation, while the necessary dose is approximately 8 to 20 times smaller than that used for myocardial perfusion scintigraphy.