Processing of liver dynamic studies with technetium-labelled sulphur colloid

Technetium 99m sulfur colloid scintigraphy to evaluate reticuloendothelial system function in dogs with portasystemic shunts

In a retrospective study, technetium 99m sulfur colloid scintigraphy was used to evaluate reticuloendothelial system function in 61 dogs with single congenital and 40 dogs with multiple acquired portasystemic shunts. Whole body reticuloendothelial function was measured by calculating the plasma clearance rate constant from a dynamic study of liver uptake of 99mTc sulfur colloid. Relative liver, spleen, and lung uptake, and a ratio of hepatic:extrahepatic uptake were measured on static equilibrium images. Results were compared with those of a group of 26 normal dogs. Compared with values for the group of normal dogs, the plasma clearance rate constant, relative liver uptake, and hepatic:extrahepatic uptake ratio were significantly decreased, and relative spleen and lung uptake were significantly increased in dogs with portasystemic shunts (P < .0001). The only significant difference between dogs with single congenital versus multiple acquired shunts was that the relative splenic uptake was higher in the former group (P < .0002). Based on these results, we concluded that dogs with portasystemic shunts have significantly impaired reticuloendothelial function. The primary cause of this dysfunction is likely a reduction in effective liver blood flow. Increases in spleen and lung reticuloendothelial activity did occur, but only partially compensated for the reduction of liver reticuloendothelial activity. Possible mechanisms for the increased spleen and lung uptake are discussed.

Perfused Kupffer cell mass. Correlation with histology and severity of chronic liver disease

The perfused Kupffer cell mass determines sulfur colloid distribution by liver spleen scan (LSS) and is proportional to the perfused hepatocyte mass. This accounts for the correlation of sulfur colloid distribution with tests of hepatic function and raises the question of whether the LSS can be used as a quantitative test of hepatic function. The recent ability to precisely measure sulfur colloid distribution by single-photon-emission computerized tomography (SPECT) prompted us to evaluate the clinical value in 329 consecutive patients with adequate LSS and clinical information, of which 27 apparent normals and 220 patients with chronic liver disease (CLD) were included in this study. The liver-bone marrow index (LBI) indicated the distribution of counts between the liver and bone marrow. The liver-spleen index (LSI) indicated the distribution between liver and spleen adjusted for spleen size. The LBI and LSI correlated with each other (r = 0.753; P < 0.001). The arithmetic mean of LBI and LSI was defined as the severity score. Detailed clinical evaluation was available in these patients and included 109 who had liver biopsy. A severity score in 27 normals was 102 +/- 5 (mean +/- SD) with all values > 85. The severity score correlated with hepatic fibrosis (r = -0.694; P < 0.001) in 109 patients with benign liver disease who had recent biopsies and with the Child-Pugh classification (r = 0.78; P < 0.001) in 220 patients with CLD.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatic reticulo-endothelial function: a correlation of radioisotopic and immunohistochemical assessment

Using an immunoperoxidase staining technique for muramidase (lysozyme)-containing cells in liver biopsies, the Kupffer cell population has been compared with the isotope liver scan abnormalities in 43 patients with various liver diseases. A significantly greater degree of scintigraphic abnormality was seen in cirrhotics compared with non-cirrhotics using both a visually assessed scan scoring technique (p less than 0.001) and computer-generated spleen-to-liver (S-L) relative activity ratios (p less than 0.01). The mean muramidase-positive cell count in cirrhotic biopsies was not significantly different from that in non-cirrhotics, neither was there any significant difference between alcoholic and non-alcoholic liver disease. The liver mass was shown to be significantly greater (p less than 0.02) in alcoholic compared with non-alcoholic disease, but even if corrections were made for this, no significant differences were found. A significant (p less than 0.02) negative correlation was found between liver scan score and muramidase-positive cell count in patients with cirrhosis but not in non-cirrhotic disorders. No significant correlations were observed if the computer-derived liver mass was taken into consideration. These results suggest that the scan defect seen in liver disease cannot be explained by loss of Kupffer cells alone, although they are consistent with the hypothesis that intrahepatic shunting plays a significant role. Chronic alcohol ingestion does not in itself appear to be a major independent influence.

Dynamic liver scanning in cirrhosis

Dynamic liver scanning using 99mTc sulphur colloid has been used in assessing 41 patients with cirrhosis and the data compared with 33 control subjects. The mesenteric fraction (MF) was significantly reduced in cirrhotics (0.30 +/- 0.17) compared with controls (0.58 +/- 0.09), P less than 0.001. The liver: spleen ratio (L:S) was also significantly different (1.6 +/- 0.95 compared with 4.9 +/- 1.4), P less than 0.001. Those patients who had undergone a recent variceal bleed had values less than patients who had not bled. Dynamic scintigraphy may be of value in monitoring the progress of disease and response to treatment.

A scintillation camera technique for measurements of the reticuloendothelial function - comparison of different methods for measuring RES function

A highly standardized 99mTc-sulphur colloid was used to evaluate reticuloendothelial system (RES)-function in the normal rat and after RE blockade by gelatin (Haemaccel). Activity distribution in the animals was measured with a scintillation camera technique. Total uptake of activity in the liver was estimated. From the time-activity curves over the liver, the phagocytic index (kphag) was evaluated. Estimation of the uptake rate of the labelled colloid into the liver and into other parts of the RES was also performed using a two-compartment model. Different methods of evaluation of RE function were compared. It was shown that for a proper estimation of the RE function, the whole uptake curve must be considered. Gelatin (Haemaccel) significantly reduced the total colloid uptake by the liver. The colloid uptake rate into the liver was also significantly reduced. Liver specimens after colloid injection were examined by light and electron microscopy showing vacuolation of hepatocytes and sinusoidal cells probably due to pinocytosis. The technique described enables functional studies of the RES. It has the advantage of noninvasive registrations and is based on the same technical facilities as used for routine liver scintigraphy.