738 Veteri7iary Obstetrics 



In the posterior presentation, the presence of hydrocephalus is 

 not likely to be suspected until the entire fetus, except the head, 

 has been extracted, when suddenly its progress is checked or 

 completely stopped, and it becomes necessary to make an ex- 

 amination in order to determine the cause. 



Handling. The indications in hydrocephalus are the destruc- 

 tion of the tumor by opening the sac and permitting the liquid 

 to escape and then diminishing the size of the osseous portion 

 by dividing the bone with the obstetric chisel. The incision 

 into the tumor is easily made with the scalpel or ring knife, and 

 the cranial bones are so thin and weak that they are easily 

 broken down by means of the chisel, as described on page 643. 

 In one case, in the mare, where the anterior limbs had not yet 

 advanced into the canal, we opened the sac and allowed its con- 



FiG. 124. Hydrocephalus. Calf, (.■\fter photograph). 



tents to escape, broke down the bones, drew the head through 

 the birth canal and amputated it, after which we repelled the 

 neck, secured the two anterior limbs and extracted the headless 

 fetus. 



When the fetus presents posteriorly, and hydrocephalus has 

 been diagnosed, the handling is analogous to that for the an- 

 terior presentation. 



As a general rule, it is not essential to decrease the size of the 

 head very greatly, or, in some cases, to decrease it at all by arti- 

 ficial means. Fig. 124 represents a hydrocephahc calf, which 

 was expelled without aid, the head-sac of which had a capacity 

 of about 5 gallons. We had been called because of the dys- 

 tokia, but, pending our arrival, the calf had been expelled. 

 Upon examination, it appeared that the expulsive efforts had 

 compressed the sac to such a degree that it ruptured through the 



