TUMOBS 119 



semi-fluid, hemmed in by a fibrous lining, covered either with, 

 endo or epithelium. 



What forms of cysts are recognised ? 



1. Degeneration cysts. 



2. Exudation cysts. 



3. Extravasation cysts. 



4. Retention cysts. 



5. Cysts of congenital origin. 



6. Genuine cysts. 



Describe degeneration cysts. 



These are cysts arising in pre-existing tumors, due to 

 fatty, mucoid, etc., degenerations taking place in the tumor. 

 These cysts contain mucoid or fatty, etc., fluids, and are 

 usually observed in sarcomata and carcinomata,- and then 

 called cysto-sarcoma, cysto-fibroma, etc. 



Describe the exudation and extravasation cysts. 



When a soft part is exposed to a contusion of sufficient 

 severity, a hematoma or lymph extravasation occurs. As a 

 result of the aseptic inflammation which follows, this fluid 

 becomes encapsulated, and a hollow neoformation containing 

 serum is the result, being in this instance an extravasation of 

 blood cysts. 



The exudation cyst is the result of excessive secretion into 

 a closed cavity, as a bursa, tendon, sheath, etc., usually the 

 result of a previous inflammation. 



Give examples of both. 



The extravasation cyst is seen about the neck and back of 

 dogs after bites or on the haunch of the horse after blows. 

 The exudation cyst is seen in the capped hock and capped 

 elbow of the horse. 



