DIFFICULTIES IN REMOVING CCENURUS CEREBRALIS. 385 



will be felt in withdrawing of the piston. In such case the pull is 

 maintained, and the syringe, drawing with it the sac and contents, 

 is cautiously raised, until the sac-wall comes in sight and can be 

 grasped with blunt forceps and completely taken away. Usually 

 the cyst contains free heads floating in the fluid, which must not 

 be thrown on the ground ; and the bladder and contents must both 

 be completely removed and destroyed. The skin wound is disinfected, 

 covered with turpentine, collodion, or tar, and usually heals 

 satisfactorily. 



Difficulties, however, are sometimes met with. Animals ap- 

 parently successfully operated on may die after a few hours, and 

 post-mortem shows bleeding from some of the larger meningeal 

 vessels. Where careful antisepsis is not carried out, inflammatory 

 processes may also result. Injury to a lateral ventricle is especially 

 dangerous, being apt to be followed by fatal hydrocephalus purulentus, 

 running its course in a few days. Frequently the cyst is in the 

 cerebellum, or a cerebral lobe, when its removal is impracticable. 

 When several cysts exist in different positions in the brain the case 

 is hopeless. Sometimes the bladder is not met with when the trocar 

 is introduced, no fluid discharges after removal of the stilette, and 

 it becomes a question whether to introduce the trocar more deeply 

 or to operate at another point. When antiseptically treated from 

 the first, the wound seldom gives much trouble, and no objection 

 exists to renewing the attempt in another place. Sometimes the 

 sac lies so deep as to be impossible of removal, and little good can 

 be done, even with the explorer first designed by Stiirig, and improved 

 by Lehmann. The injuries inseparable from the use of this instru- 

 ment do not, however, occasion any particular danger. 



Rams with large well-developed horns give most trouble. In 

 them the frontal sinuses are large, and cover so much of the skull 

 that only the posterior folds of the cerebrum can be directly reached 

 from the exterior. Moller endeavours, in such cases, firstly, to trephine 

 the frontal sinus, and thence to open the roof of the cranium with 

 a trocar. It is difficult, however, to make the frontal sinus aseptic, 

 and, in rinsing it out, large quantities of fluid pass into the nasal 

 chambers, producing difficulty in breathing. Hence, during the 

 operation, the head should be pendulous, though this is attended 

 with considerable discomfort to the operator. The easiest subjects 

 are ewes, in which both skin and bone are alike thin. 



At best the losses are heavy. Generally only 10 per cent, are 

 saved, and of these some die later of the sequelae of the disease. The 

 operation is usually confined to rams and specially valuable animals. 

 r.s. c c 



