The visualization of femoral vessels in delayed bone scans--a sign of arteriosclerosis? A comparison of 99mTc-MDP and 99mTc-DPD.

The activity of femoral vessels in delayed bone scans was evaluated visually in 237 consecutive patients and quantified in 40 female patients. In visual analysis the patients were randomly divided into three groups and in quantitative analysis into four groups of equal size. Two different MDP preparations and one DPD preparation were used as bone-seeking agents. With aging, the activity in femoral vessels increased with all agents in visual analysis, significantly with MDPs (P less than 0.001) between patients less than or equal to 60 years and greater than 60 years. In female patients with all agents a significant increase in femoral activity was found (P less than 0.001 with MDPs, P less than 0.05 with DPD). In patients greater than 60 years, the femoral uptake was significantly higher with MDP when compared with the DPD uptake (P less than 0.01 with MDP1, P less than 0.05 with MDP2). Between the MDPs no significant differences were found. In quantitative analysis the femoral vessel to soft tissue ratio was significantly higher in patients greater than 70 years when compared with patients less than or equal to 50 years with MDP. No difference was found with DPD. Histological examination of excised arteries of ten patients with intense femoral uptake of MDP showed arteriosclerosis and calcification in all cases. The findings suggest that the femoral visualization in delayed bone scans is probably related to arteriosclerosis and is not a non specific finding. There may be age-related differences in the distribution of MDP and DPD.

99Tcm-MDP and 99Tcm-DPD in pathologic bone lesions. A visual and quantitative comparison.

The efficiency of 99Tcm-methylene diphosphonate (MDP) and 99Tcm-dicarboxypropane diphosphonate (DPD) to detect pathologically increased bone uptake was evaluated both by computed quantitative intra-individual and visual inter-individual comparison. Twelve patients with altogether 44 metastases in ribs and lumbar vertebrae were evaluated quantitatively. The lesion to normal bone ratio (mean +/- SD) was, with MDP, 2.9 +/- 1.6 and with DPD 2.4 +/- 1.2 (p less than 0.001), and the normal bone to soft tissue ratios with MDP 8.5 +/- 5.0 and with DPD 9.4 +/- 6.1 (NS). Visual analysis of 162 patients with 334 focal lesions showed no significant difference between two MDP preparations and one DPD preparation. Visual and quantitative comparison in the three most common malignancies studied (breast, prostatic, and lung carcinoma) gave the same result. Because the lesion to normal bone ratios were high with both agents, and there was no significant difference on visual analysis, both radiopharmaceuticals are considered to be relevant bone seeking agents and the difference between MDP and DPD is only academic and not of practical value.

Comparison of gallium-67 citrate and technetium-99m glucoheptonate in the evaluation of pulmonary malignancies.

Sixty-five patients with suspected or proven pulmonary malignancy were examined with [67Ga]citrate and [99mTc]glucoheptonate ([99mTc]GH) scintigraphy. In the final diagnosis 39 had primary lung carcinoma, four metastases in lung, mediastinum, and pleura from carcinomas elsewhere, and 22 benign pulmonary diseases. The sensitivity in the detection of pulmonary malignancies was 91% with 67Ga and 95% with [99mTc]GH. The intensity of uptake was somewhat greater with 67Ga than with [99mTc]GH in almost all malignant lung tumor groups. The specificity to detect malignant tumors was 82% with both radiopharmaceuticals. Irradiation and chemotherapy seemed to decrease 67Ga uptake but not [99mTc]GH uptake. Only four of 22 benign diseases showed accumulation of both 67Ga and [99mTc]GH. The intensity of uptake in benign processes was almost equal with that in malignant diseases, but most malignant processes were better delineated than the benign lesions. There were many differences between 67Ga and [99mTc]GH uptake, which suggest different mechanisms of accumulation of these agents. It is concluded that some 67Ga studies could be replaced by cheaper and more practical [99mTc]GH.

Better visualization of a lung tumour with 99mTc-DPD than with 99mTc-glucoheptonate or 67Ga-citrate.

A case of a squamous cell lung carcinoma detected with 99mTc-DPD, 67Ga-citrate and 99mTc-glucoheptonate (GH) is reported. The highest uptake was seen with DPD and the lowest with 67Ga. Emission-computed tomography was very useful in DPD imaging but gave less new information in GH and 67Ga studies in comparison to traditional planar imaging. The patient had been given both irradiation and chemotherapy, which might be the cause of good accumulation of DPD and rather poor accumulation of GH and 67Ga.

The spleen-to-liver ratios in hepatic diseases.

We compared light pen (LPEN) and Region of Interest (ROI) computer methods in determining spleen-to-liver (S/L) ratios both in anterior and posterior images in various liver diseases. The S/L ratio was independent of age or type of colloid used (equal particle size provided). Results with corresponding LPEN and ROI programs did not differ significantly from each other. The sensitivity and specificity were tested and the anterior view yielded somewhat better results than the posterior view but the best results were obtained when both projections were used. The sensitivity for all liver diseases was 60% and the corresponding specificity 93%. In hepatocellular diseases the sensitivity was 80-100%, but the S/L ration had only 37% sensitivity for hepatic metastases. Hepatomegaly in the anterior view was found in 67% of fatty liver cases, in 25% of cirrhosis cases, in 20% of hepatitis and in 25% of metastatic livers. Splenomegaly was noted in 39-54% of patients with hepatocellular diseases but only in 4-10% of metastatic diseases.

A clinical comparison of 99mTc-DPD and two 99mTc-MDP agents.

Two hundred and fifty-seven patients were studied with bone-seeking radiopharmaceuticals. They were randomly divided into three groups. Two groups were injected with two different 99mTc-methylene diphosphonates from two manufacturers (MDP 1 and MDP 2) and the third group with 99mTc-dicarboxypropane diphosphonate (DPD). DPD was found to be superior with respect to blood clearance, femur to soft tissue ratio and subjectively assessed image quality. There seemed to be no marked differences between the bone-seeking agents in the visualisation of pathological foci. The image quality seemed to be better in the MDP 2 group than in the MDP 1 group but they were similar in other respects. The femur to soft tissue ratio decreased with increasing age in the DPD group but not in the MDP groups. With all agents worsening of scan quality with increasing age was noted and the image quality was better with men than with women. When short incubation times of radiopharmaceuticals were used before injection, the bone to soft tissue ratio was lower and the scan quality was poorer than with incubation times longer than 20 min.

Tc-99m glucoheptonate in detection of lung tumors.

Sixty-three patients aged 21-80 yr were examined. Tc-99m glucoheptonate (Tc-GH) scintigraphy was performed in 32 patients: 26 with primary lung carcinoma; six with metastases in lung, mediastinum, and pleura from carcinomas elsewhere; eight with benign pulmonary diseases; and 23 without known pulmonary disease. Tc-GH accumulated in 23 of 26 primary pulmonary carcinomas as active foci. The specificity of Tc-GH scans for neoplasm detection was higher than that of chest radiographs. The visualization of malignant tumors was much better in the late Tc-GH images (5-6 hr) than in the early (1 hr). Metastases from other carcinomas were positive in four of six patients, but they were considerably better detected in the radiographs, except in one patient with metastatic hepatocellular carcinoma. Neoplasms or their metastases in the hilar and mediastinal regions were better detected in the Tc-GH scans than in the chest radiographs. Only one of eight benign lung processes was visualized (as a weak diffuse accumulation of Tc-GH in hilar scar formation), and 23 patients without pulmonary disease had no pathological foci.