Cavernous hemangiomas are the benign tumors that are accidentally detected because most of them are asymptomatic. Differential diagnosis between cavernous hemangiomas and other hepatic lesions especially metastasis are clinically important. The aim of this study is to evaluate the cost-effectiveness between Tc-99m labeled red blood cell (RBC) and computed tomography (CT) in the diagnosis of hepatic cavernous hemangioma. Nine Tc-99m labeled RBC studies collected between 1996-2003 and 26 CT studies collected between 2002-2003 were analyzed. The sensitivity, specificity, accuracy and 95%confidence interval (95%CI) of both techniques were determined by using the results of either angiography, surgery, biopsy or follow-up as the gold standard. Cost effectiveness ratio and sensitivity analysis of both techniques were compared. The specificity, sensitivity and accuracy of Tc-99m labeled RBC were 83.3% (95%CI 35.9, 99.6) , 100% (95%CI 29.2, 100) and 88.9% (95%CI 51.8, 99.7), respectively while CT showed 88.9% specificity (95%CI 51.8, 99.7), 100% sensitivity (95%CI 80.5, 100) and 96.2% accuracy (95%CI 80.4, 99.9). Cost effectiveness ratio of Tc-99m labeled RBC according to the effect of specificity, sensitivity and accuracy were 93.57, 77.67 and 88.26, respectively while those of CT were 158.04, 140.65 and 146.51, respectively. The sensitivity analysis curves of Tc-99m labeled RBC and CT did not cross. This means that Tc-99m labeled RBC was more cost effective than CT and no matter CT improved its sensitivity, specificity and accuracy, it could not be as cost effective as Tc-99m labeled RBC. For hemangioma, cost-effectiveness ratio of specificity is very meaningful. In our study, Tc-99m labeled RBC is more cost-effective than CT because of its lower cost. We suggest that Tc-99m labeled RBC should be concerned as an appropriate technique to differentiate between hemangioma and liver metastasis.

M.Sc. RADIOLOGICAL SCIENCE คณะ FACULTY OF MEDICINE SIRIRAJ HOSPITAL มหาวิทยาลัยมหิดล ปี 2547

effectiveness, Cost, CAVERNOUS, COMPUTED, HEMANGIOMA, HEPATIC, LABELED RED BLOOD CELL, Tc-99m, TOMOGRAPHY