GOITER—STRUM A— BRONCHOCELE 339 



Cystic Goiter.— Definition.— An enlargement of one or 

 both thyroid glands, characterized by the formation of cysts 

 which may be single or multiple. In cases of long standing, 

 calcification of the cyst wall may take place. The cause of 

 cystic goiter has never been clearly proved. When hemor- 

 rhage occurs in the gland follicles they are distended, certain 

 changes in the contents result, and there is left a more or 

 less clear serous fluid. Further, through disturbance in the 

 glandular activity, from injury, nervous influences, or hyper- 

 emia, the circulation of the glands is abnormal leading to 

 extravasation of serum into the follicles which may result 

 in a permanent cystic condition. Cysts commonly compli- 

 cate parenchymatous goiter. 



Symptoms.— An enlargement of one or both of the thyroid 

 glands is the most prominent symptom. Many cases 

 develop rather suddenly while others require considerable 

 time before the glands reach a sufficient size to become 

 noticeable. As a rule, unless complicated with other forms 

 of goiter, no general symptoms will be present. Should the 

 cystic formation involve both glands it is quite possible that 

 the normal function of the glands will be disturbed, then 

 general symptoms will result. Pressure on the vagus, sym- 

 pathetic, and recurrent nerves may lead to complications 

 as in parenchymatous goiter. In the majority of cases the 

 course of this goiter is chronic, and aside from the unsightly 

 enlargement they produce, the animal will not suffer any 

 inconvenience. Examination of the gland by careful palpa- 

 tion will reveal the soft, fluctuating swelling, the absence of 

 inflammation, and a consistency differing from other forms of 

 goiter. 



Diagnosis. —The diagnosis can be made positive by the 

 examination, and if necessary by the use of an exploring trocar 

 to obtain some of the yellowish or clear serous fluid. 



Prognosis.— Favorable when proper and prompt treatment 

 is used. Further, as this is in most cases a local condition 

 confined to the gland, remedial measures can be applied more 

 satisfactorily. 



Treatment.— This is of two kinds, viz.: (a) Medical, and 

 (b) surgical. 



