Diagnosis of hepatic hemangiomas with 99mTc-labeled red blood cell scanning: value of SPECT.

99mTc-labeled red blood cell (RBC) scanning is considered a highly specific technique for the study of hepatic hemangiomas. However, planar imaging displays poor sensitivity for the identification of small lesions. The authors consider a survey group of 119 patients, of whom 66 with a presumed diagnosis of hepatic hemangioma, for a total of 77 lesions ranging from 0.8 to 15 cm in diameter. The study was conducted with three-phase planar imaging and single photon emission computed tomography (SPECT). The results, which confirm a high specificity of 99mTc-RBC scanning (100%) in the study of hepatic hemangiomas, show that SPECT significantly improves the detection of these lesions (71%) compared to the delayed static study (52%), with the largest gain for lesions between 2-3.5 cm (83% versus 51%). However, also SPECT has difficulty in detecting lesions of less than 2 cm. With regard to three-phase imaging, the authors point out that the pattern considered characteristic for hepatic hemangiomas (perfusion blood-pool mismatch) is infrequent (13%).

[Experimental evaluations of ther preferential use of Tc99m and In113m in hepatic scintiscanning]. / Valutazioni sperimentali sull'impiego preferenziale del 99mTc e del 113mIn en epatoscintigrafia.

A hollow perspex dummy was filled with radioactive fluid to simulate the liver, cold nodes being represented by paraffin balls of diameter varying from 2.5 to 4.0 cm, variously located. Scans were carried out with a linear scanner using 99mTc and 113mIn as tracers. Advantages and drawbacks of the two tracers in demonstrating cold areas in the liver are compared and discussed.