CHAP. VII.] 



BILIARY CALCULI. 



379 



1 x. 



pyramidal masses of cholesterin : (3) a laminated external layer or 

 shell. 



"The nucleus commonly presents a brownish-black or greenish 

 colour, and is usually formed of a combination of biliary pigments 

 with calcium. The nucleus is sometimes solid, sometimes hollowed 

 as a result of a process of desiccation, in which case a more or less 

 subdivided cavity exists. Sometimes, the nucleus contains concrete 

 mucus (Ch. Robin, Frerichs), or shrivelled epithelial cells (Frerichs). 

 Finally, the nucleus has sometimes, though very rarely, been found 

 to contain foreign bodies, the existence of which Cruveilheir in- 

 correctly denied. In the famous often-quoted case of Lobstein, 

 which he figured in the Atlas accompanying his Traite d'Anatomie 

 Pathologique, a desiccated Ascaris lumbricoides formed the nucleus 

 of the calculus. In the subject which furnished this calculus, thirty 

 other ascarides were found in the biliary passages. 



" As examples of foreign bodies constituting the nuclei of biliary 

 calculi may be cited the following : (1) the case of Naucke, in which 

 a needle two centimetres long formed the centre of a biliary con- 

 cretion of the size of a walnut ; (2) the case recorded by Buisson, 

 in which the centre of the nucleus consisted of a small aggregation 

 of blood; (3) a case recorded by the same observer, in which the 

 nucleus of a biliary calculus in an ox was formed by a Distoma 

 hepaticum ; (4) I would remind you of the fact that Thudichum has 

 found the nuclei of a certain number of biliary calculi obtained from 

 the same gall-bladder to be formed of branching filaments, evidently 

 representing moulds of the interior of small intra-hepatic biliary 

 ducts and which appear to have played the part of centres of 

 formation of the concretions 1 . 



" Little remains to be said concerning the structure of the middle 

 layer of gall-stones. This layer is usually, as has been previously 

 stated, composed of crystals of cholesterin and presents a radiated 

 aspect. Sometimes the radiations are interrupted by concentric 

 striae or layers which cut the crystalline pyramids perpendicularly 

 to their long axis. The middle layer is either quite white or trans- 

 parent or, on the contrary, more or less coloured. In the latter case, 

 the biliary pigment has intermingled in varying proportions with the 

 cholesterin, which in the former case was free from it. Rarely, the 

 middle layer, though composed of cholesterin, presents a soapy 

 uniform aspect, without stratification and without any evidence of 

 crystalline structure. 



" The laminated external shell is observed in the larger number 

 of cases. Yet, as has been stated, it is sometimes absent. In such 



1 The accuracy of this observation is denied by Naunyn, ' Thudichum hat behauptet, 

 dass sich in dem Centrum der meisten Blasengallensteine Abgusse von Lebergallen- 

 gangen fanden. Er meinte, dass diese Gallengangscylinder gewohnlich den Krystalli- 

 sationskern fiir die Gallenblasenconcremente bildeten. Nach den Abbildungeu, die 

 Thudichum von seinen Gallengangscylindern giebt, kann ich nur sagen, dass ich sie 

 nie gesehen habe.' Klinik d. Cholelithiasis, p. 49. 



