Common bile duct stones from 59 consecutive patients who underwent cholecystectomy more than 1 year before radiological detection of choledocholithiasis (group I) and from 31 consecutive patients with choledocholithiasis and gallbladder in situ (group II) were subjected to chemical analysis and compared with the composition of gallbladder stones from the same population (two consecutive biopsy and autopsy series, n = 343). In contrast to cholecystolithiasis, inorganic calcium salts were infrequent in choledocholithiasis while calcium bilirubinate and fatty acid calcium salts played an important role in the composition of common bile duct stones. This is of particular importance in terms of litholysis. With respect to stone pathogenesis, clinical and radiological data were analyzed, as was hepatic bile lipid composition. There was no significant difference in the lithogenic index (percent cholesterol saturation) in cholecystectomized and in non-cholecystectomized patients with choledocholithiasis. The most important cause of stone recurrence in the common duct after surgery was incrustation of unabsorbed suture material, which was the case in 30.5% of group-I patients.

Eighty in vitro experiments were performed with single (n = 51) or multiple (n = 29) gallstones in order to find out which parameters are of prime importance for their disintegration by extracorporeal shock waves. A Dornier lithotripter and an upper limit of 1,500 discharges were employed. Although computed tomography density was significantly lower in cholesterol stones than in the noncholesterol stones (p less than 0.0001) and although the latter were significantly more often radiopaque (p less than 0.0001), we found no clear-cut correlation between the cholesterol content or computed tomography density and the degree of fragmentation of the stones. The most important variable which limited successful disintegration was the total stone volume. In stones with a mean total volume of 0.83 ml +/- 0.25 S.E. (diameter for single stones = 11.5 +/- 0.9 mm), none of the fragments exceeded 2 mm, whereas in stones with a mean volume of 3.6 ml +/- 0.64 (diameter = 17.2 +/- 1.5 mm) at least one fragment larger than 2 mm remained (p less than 0.002). Under the in vitro conditions, fragmentation was similar in multiple and solitary stones, provided the volume of the stones was comparable. These data show that, in general, the number and size of the stones, i.e. their total volume, and much less significantly their chemical composition are the major determinants of fragmentation by extracorporeal shock waves.

No abstract

Freshly precipitated unconjugated bilirubin (UCB) is solubilized rapidly and to a large extent by the sodium salts of di- and trihydroxy bile acids. The solubilization effect depending on bile salt concentration, pH and ionic strength is based on micellar mechanisms.

The efficacy of a buffered 1% ethylenediaminetetraacetic acid (EDTA)-2Na solution (pH 9.2) in solubilizing carefully pulverized material from brown bilirubinate and black polybilirubinate pigment stones can be intensified stepwise by admixtures of detergents and mucolytic active thiols. Solubilization effects were quantified either photometrically by measuring the dissolved calcium bilirubinate or gravimetrically by measuring the total weight loss of solids after a defined incubation period. Maximum effects were achieved when using a buffered solvent with 1 g/dl disodium-EDTA, 1 g/dl sodium taurocholate (NaTCA), and 2 g/dl N-acetylcysteine (NAC). Whereas admixtures of NAC enhanced the solubilization of brown bilirubinate stone material additionally by an average of 21.3% (related to the effect of an EDTA/NaTCA-containing solvent), black polybilirubinate material responded rather poorly and inconsistently to NAC (mean, 8.4 +/- 11.7%).