CHAPTER IV. 



THE THYROID AND ADRENALS. 

 The Thyroid. 



Malformations . 



THE thyroid gland is sometimes very small, either as the result of atrophy (Fig. 

 214) or as a congenital deficiency. For the relationship of this condition to cretinism 

 and myxcedema see page 361. 



FIG. 214. SECTION' OF THE ATROPHIED THYROID GLAND IN MYX<EDEMA. 



a, Interstitial tissue ; b, atrophied lobules with small spheroidal-celled or lymphatic tissue in their peripheries. 



The thyroid may be irregularly lobulated. There may be small accessory glands 

 situated at some distance from the normal position, as in the mediastinum or pleura. 



DEGENERATION. 



Colloid degeneration of the epithelial cells of the gland, and the filling 

 of the alveoli with colloid material, are of common occurrence, and when 

 in moderate degree may be regarded as normal, since a certain amount of 

 this change is found in many otherwise apparently normal glands. It 

 may occur, however, to such an extent as to constitute an important 

 lesion (see below). 



Amyloid degeneration, particularly of the blood-vessels, is of infrequent 

 occurrence. 



Hyalin degeneration of the stroma of the thyroid may occur. 



