THE THYROID APPARATUS 73 



of total extirpation. Where these do not appear, either the gland 

 was not removed in its entirety, or accessory thyroids are present. 

 Symptoms of cachexia may appear after partial extirpation of 

 goitrous glands. In such cases, however, the symptoms are 

 much milder and the condition is one of mitigated cachexia 

 thyropriva, analogous to Hertoghe's spontaneous "chronic 

 benign hypothyroidism." 



The evil consequences of treating goitre by the surgical 

 method may be largely avoided, if a proportion of the glandular 

 tissue is allowed to remain in situ. It is hardly possible to define 

 the exact quantity. Kocher thinks that, in the case of diffuse 

 goitres, at least a quarter of the gland must be preserved if 

 dangerous symptoms are to be avoided. 



There is sometimes spontaneous recovery from the symptoms 

 of suppression which follow total extirpation of the thyroid. 

 These coincide with the growth of a so-called "goitre relapse," 

 and the improvement is explained by the fact that the new 

 formation is not of goitrous tissue, but is a hyperplastic develop- 

 ment of remains of normal glandular tissue which were left in situ. 

 These cases are instances of autotransplantation. On the other 

 hand, cachexia may develop after partial extirpation of a goitre, 

 the phenomena in this case making their appearance at the 

 moment when goitrous degeneration appears in the remains of 

 the lobe, or in the lobe of the other side. As Kocher points out, 

 there are goitres and goitres. In one case, goitre may be the 

 result of hyperplasia of functionally active thyroid tissue ; in 

 another, it may mean a degenerative process leading to sup- 

 pression of the normal thyroid function. 



TRUE ATHYROSIS AND HYPERTHYROSIS. 



Having given an account of the results which follow the 

 operative removal of the thyroid gland, it is fitting that those 

 genuine clinical conditions which are brought about, to the best 

 of our knowledge, by the suppression of its function should next 

 be described. The first of these is myxcedema adultorum, 

 generally known as myxcedema. It is not necessary to describe 

 the symptoms of this condition, for to do so would be to repeat 

 the clinical description of cachexia strumipriva. The identity of 

 the symptoms justifies the name of "operative myxoedema," 

 which is sometimes given to cachexia strumipriva. Moreover, 

 though the post-mortem findings in true myxcedema are somewhat 

 scanty, they show that this condition, like cachexia strumipriva, 

 owes its origin to the suppression, or to the conspicuous reduction, 

 of the activity of the thyroid gland. The thyroid is invariably 

 much reduced in size and occasionally completely atrophied ; 

 it is pale in colour, and, under the microscope, shows obliteration 

 of the glandular parenchyma together with proliferation of the 



