A quantitative index measured on 99mTc GSA SPECT/CT 3D fused images to evaluate severe fibrosis in patients with chronic liver disease.

PURPOSE: We compared quantitative indices estimated by use of technetium-(99m) galactosyl human serum albumin ((99m)Tc-GSA) single-photon emission computed tomography (SPECT)/computed tomography (CT) fused imaging and hepatic fibrosis in patients with chronic liver disease. MATERIALS AND METHODS: On the basis of pathological findings we divided 161 patients into non-severe and severe fibrosis groups (n = 81 and n = 80, respectively). We measured 2 indices by (99m)Tc-GSA SPECT/CT fused imaging: liver uptake value (LUV) = [radioactivity (whole liver)/radioactivity (injected)] × 100/body surface area, and functional liver index (FLI) = [radioactivity (hepatocytes)/radioactivity (injected)] × 100/liver volume. We compared these indices with biochemical and histopathological results. RESULTS: Univariate and multivariate analyses showed that FLI, LUV, LHL15, and prothrombin time were significant independent predictors of severe fibrosis. On the basis of receiver operating characteristics analysis, the areas under curve values of FLI, LUV, LHL15, and prothrombin time for predicting severe fibrosis were 0.83, 0.73, 0.69, and 0.68, respectively. Using an FLI value of 0.053, it was possible to predict severe fibrosis with 65 % sensitivity, 88 % specificity, and 76 % accuracy. CONCLUSION: Assessment of functional hepatocytes by use of (99m)Tc-GSA SPECT/CT fused images is useful for identifying pathological liver fibrosis.

Fused 99m-Tc-GSA SPECT/CT imaging for the preoperative evaluation of postoperative liver function: can the liver uptake index predict postoperative hepatic functional reserve?

PURPOSE: To evaluate the role of hepatic asialoglycoprotein receptor analysis in the preoperative estimation of postoperative hepatic functional reserve. METHODS: We obtained technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin (99mTc-GSA) SPECT/CT fusion images in 256 patients with liver disease scheduled for hepatic resection. The liver uptake value corrected for body surface area [LUV(BSA)] and liver uptake ratio (LUR) of the remnant were preoperatively estimated based on the fused images. These values were compared with the postoperative hepatic functional reserve. RESULTS: Significant correlations were observed between LUV(BSA), LUR, and most conventional indicators of hepatic functional reserve. Postoperatively, nonpreserved liver functional reserve was observed in 15 of the 256 patients (5.8%). Remnant LUV(BSA) showed better correlation than remnant LUR or the other indicators. No patients with remnant LUV(BSA) above 28.0 manifested poor nonpreserved functional reserve. Using a LUV(BSA) of 27.0, it was possible to predict postoperative poor hepatic functional reserve at a sensitivity of 91%, specificity of 81%, and accuracy of 81% postoperatively. According to multivariate analysis, a low remnant LUV(BSA) was the only significant independent predictor of poor hepatic functional reserve. CONCLUSIONS: Our 99mTc-GSA SPECT/CT fusion imaging method was clinically useful for evaluating regional hepatic function and for predicting postoperative hepatic functional reserve.

Clinical usefulness of a collimator distance dependent resolution recovery in myocardial perfusion SPECT: a clinical report from a single institute.

OBJECTIVE: Imperfect image resolution because of finite-sized collimator channels often causes a decrease in diagnostic performance in myocardial perfusion single-photon emission computed tomography (SPECT). This prompted us to evaluate the clinical usefulness of collimator distance dependent resolution recovery (RR) in myocardial perfusion SPECT. METHODS: We retrospectively reviewed myocardial SPECT images of 60 consecutive patients (26 men, 34 women; mean age 68 years). They consisted of 25 with coronary artery disease (CAD) and 35 without, as confirmed by the coronary angiography (CAG). The patients had undergone myocardial perfusion SPECT imaging with thallium-201 (111 MBq) under an exercise or pharmacological stress protocol. Two readers reviewed the myocardial SPECT images for the presence of CAD on a 4-point scale where 0 = normal, 1 = probably normal, 2 = probably abnormal, and 3 = abnormal. Three reading sessions were held: first, ordered subsets expectation maximization (OSEM) SPECT images, second, OSEM with RR images, and third, both OSEM and RR images. Diagnostic performance for accuracy of coronary arterial stenoses was compared for OSEM, RR and both the images. RESULTS: The sensitivity increased using RR images, but specificity decreased, and thus overall diagnostic accuracy was decreased, as compared with using OSEM images. The overall accuracy of using both the images showed the highest diagnostic performance among the three sets of image interpretations. The sensitivity, specificity and accuracy were 33, 92, 77% for OSEM, 53, 79, 72% for RR and 51, 90, 80% for both the images. CONCLUSIONS: These results suggest that RR for myocardial perfusion SPECT imaging has some potential to improve diagnostic accuracy, but both OSEM and RR image sets may have to be employed for the best diagnosis of CAD.