284 DAVID MAKINE 



culosis, marasmus, diabetes, cancer, senile dementia, etc. The gland is 

 reduced in size, sometimes by half its original volume. This reduction in 

 size is due mainly to losses of epithelium and colloid. The gland often is 

 flaccid and tough, due to the relative increase in stroma. Microscopically, 

 the blood vessels show varying degrees of sclerosis ; the alveoli are smaller 

 and more variable in size ; the lining epithelium is less uniform ; there 13 

 a tendency to heaping up and desquamation. Colloid material is in gen- 

 eral much reduced, though isolated alveoli may be distended with dense 

 colloid true colloid retention cysts. These changes are commonly 

 associated with other secondary changes, as scar formation, pigmentation 

 from old hemorrhage, both in the stroma and in the alveoli, small cysts 

 often containing cholesterol, calcification and hyaline degeneration. Pilliet. 



Atrophy Following Castration and Iodin Administration. Thyroid 

 changes following castration or following the administration of iodin while 

 having something in common with atrophy are more properly designated 

 involutions. One sees from time to time descriptions in the literature de- 

 scribing a peculiar form of atrophy due to iodin. This is wrong. Both 

 castration and the administration of iodin produce morphological changes 

 characterized by flat cuboidal epithelium and dense colloid indicative of de- 

 creased cellular activity. In the case of castration this is part of the de- 

 creased demands of the organism as a whole for thyroid function. The ad- 

 ministration of iodin lessens the cellular activity of the thyroid by supply- 

 ing the distinctive element of its secretion. Vitry and Giraud. 



Pressure Atrophy. Pressure atrophy is usually seen about ade- 

 nomata. The rapid growth of an adenoma stretches the surrounding 

 thyroid tissue and if the growth is marked, pressure destruction of the alve- 

 oli of the non-adenomatous thyroid about the tumor takes place. All the 

 non-adenomatous thyroid of a lobe may be thus destroyed. In districts 

 where endemic goiter is common, the so-called struma nodosa, or ade- 

 nomatous goiter frequently causes extensive pressure atrophy of the non- 

 adenomatous thyroid. 



Exhaustion Atrophies (see Fig. 15). These are associated with the 

 symptom complexes seen in Dercum's disease, in cretinism and myxedema. 

 There is no evidence that these are primary thyroid diseases but rather the 

 result of some systemic or general metabolic disturbance. Getsowa. 



Often in young very obese individuals and practically constantly 

 in the special form of obesity described by Dercum, one finds well marked 

 atrophic changes. It is a widely held opinion that there is a definite re- 

 lationship between the thyroid atrophy and the clinical manifestations. 



The atrophies seen in endemic cretinism and in myxedema in man 

 and the lower animals are the most striking examples of exhaustion atro- 

 phy. This subject has already been referred to under "Hyperplasias" bo- 

 cause all the evidence indicates that these atrophies occur in the late stages 

 of active hyperplasias and in spite of the attempts of the gland cells to re- 



