236 ACKOMEGALIA 



This author also attributes the changes in the vertebral column, in the 

 clavicle, in the muscular and ligamentous insertions upon the occiput to one 

 predominating factor, the increase in weight of the head. This view is more 

 reasonable than that which explains the pathologic process as due to a gen- 

 eral irritative growth of bony tissue. There is another beautiful proof of 

 Sternberg's theory which, so far as I know, has not been noticed by former 

 investigators. The pneumatic spaces in the bones of the skull are produced 

 by an absorption of the bony substance. The bone is of the same type as that 

 found in the so-called " functional " bony structures which are best recognized 

 in the spongiosa, and which become modified by the slightest pressure or the 

 slightest added weight of the bones so as to produce a structure suited to the 

 mechanical necessities of the situation. Since the functional structures in 

 acromegalia (the frontal sinuses) develop so enormously, we may look upon 

 this as a proof that the new formation of bone in these cases, unlike that in 

 leontiasis ossea, or in general h3^erostosis, is not due to a pathologic osteo- 

 plastic activity, but is an adjustment to special requirements of the bone. 



If, then, we accept Sternberg's view, and suppose that such a secondary 

 bony proliferation accounts for the hypertrophy of the zygomatic arches, at 

 the base of the skull, in the vertebral column, etc., then the hyperplasia of the 

 apparatus of mastication, especially of the lower jaw, would have to be 

 assumed as the primary change. I, however, see no reason to stop here; I 

 think we may assume that the hyperplasia of the lower jaw is itself sec- 

 ondary, since this bone, too, shows throughout a uniform extension, so that 

 its deformities may be explained as chiefly the effect of an increased strain 

 on the insertions of the muscles and ligaments. 



In this case the actual primary change would consist in an enlargement 

 of the soft parts, and especially of the tongue, which may be considered respon- 

 sible for the position of the jaws from the fact that by its increased volume, 

 for which the oral cavity is no longer adequate, it exerts pressure upon the 

 jaws. In fact the macroglossia is a characteristic feature of the clinical pic- 

 ture, and to this I should like to ascribe a dominant role in producing the 

 change in the face, including the soft parts, namely, the lips and the nose. 

 The tongue has repeatedly been examined microscopically by others as well as 

 by myself. A prominent part in the hyperplasia is made up by the mucous 

 membrane, which is completely covered with wart-like proliferations of the 

 papillae which are also distributed in the sub-papillary layers. Within the 

 muscular strata broad, abnormal, connective tissue strands appear. Whether 

 the musculature itself is increased cannot be decided. From the examination 

 of my preparations I do not, however, concur in the view sometimes expressed 

 that degeneration of the muscular fibers is present. I was able, by new stain- 

 ing methods, to show the transverse striation with such clearness that I have 

 utihzed the preparations of acromegalic tongues as objects with which to 

 demonstrate transverse striped muscles. I must assume, therefore, that de- 

 generation of the tongue muscles, like that more frequently mentioned in 

 the muscles of the body, must be accounted for as one of the late marantic 

 phenomena of the affection. 



With Striimpell I shall mention the changes in the soft parts of the ex- 



