Abstract
An improved technique for the hypophysectomy in dogs and cats is described. This is a modification of McLean's buccal method in dogs. The operation is performed under the barbiturate anaesthesia in dogs and by the subcutaneous injection of ether in cats. No assistant service is neccessary. The benzalkonium chloride solution is adopted to simplify the sterilization of instruments, gauze, cotton and operative field. Characteristic advantages of this technique are as follows. A clod of clay wrapped in a sterilized vinyl sheet is used conveniently for the head fixation. Three kinds of hooks are used snugly for drawing the tongue, for lateral retraction of the incised edges of the soft palate and of the freed edges of the mucoperiosteum of the sphenoid bone. A clear-cut oval hole is produced in the sphenoid bone by the dental points (No. 9 & 20). Accordingly the gauge and the mallet are -not neccessary throughout the perforation. Moreover the dental points will serve to prevent the bleeding in the diploe. A very small steel plate probe is convenient to separate the pituitary from the attachment to the diaphragma sellae. The stalk section before the suction of pituitary will protect the hypothalamus from injury. After the removal of the pituitary the defect hole is filled with penicillin. The nasopharyngeal mucous membrans is sutured and it is not neccessary to close the periosteum.
In cats and puppies the haemorrhage in the diploe is generally rare, so that the operation will be very easy. In some dogs, however, the haemostasis during perforation may prove to be tedious, although it will not make the pituitary extirpation itself impossible. Even if operative procedures through the dura opening extend beyond 1 hour by some accidents, the danger of meningitis would be prevented by the local and systemic administration of penicillin.
The average duration of this operation are about 1 hour or less, 1 to 2 hours and 3 hours or more, respectively, in cats, puppies and dogs. In view of the simplicity and the short duration of the operation and additionally rapid recovery, this technique would be most suitable in cats and puppies.
