gunther’s catheter in chronic catarrh of guttural pouches. 117 
little value in treatment though it is sometimes used for diagnostic 
purposes. 
It consists of a brass tube about 20 inches in length ; one end 
is closed, but is provided with two lateral openings, and is some¬ 
what curved. The other end is also slightly bent, possesses a long 
opening to take the so-called index, and receives the screw of an 
iron handle. The index consists of a spring, about 8 inches long, 
and serves to fix the distance of the Eustachian tube from the 
entrance to the nostril. By marking with the spring the dis¬ 
tance of the temporal canthus, which lies at an equal distance 
from the entrance to the nostril, one knows, on introducing the 
instrument, when the upper end has attained the Eustachian 
tube. To use the catheter the patient’s head must be moderately 
extended. After applying the twitch and fixing the spring, the 
tube is passed, the bent end directed towards the palate, into 
the lower meatus of the nostril, until the index shows that the 
end of the instrument has attained the entrance of the Eusta¬ 
chian tube. A quarter turn is then made with the handle of 
the instrument, so that the point is directed to the side, and the 
handle of the catheter pressed towards the septum nasi, probing 
movements being made, until the sound passes into the guttural 
pouch. Unopposed progress of the instrument, without back 
pressure, shows that it has entered the pouch. The handle is 
now removed, and the contents of the sac allowed to. flow 
through the tube. In a similar manner fluids may be injected 
into the sac through the tube. Where the catheter is passed 
in an animal which has been cast, the mouth should be placed 
rather higher, in order to bring the bent point of the cathetei 
sideways into the Eustachian tube, by moving the handle 
towards the septum nasi. 
For opening the guttural pouch various operations have 
been recommended, all of which have their advantages and 
their drawbacks. Although very quiet horses have been 
operated on standing, most operators will piefei the prone 
position. Where excessive dyspnoea exists, it may, however, 
be aggravated by casting, and Leblanc and others recommend 
that tracheotomy should first be performed ; but this seems 
undesirable, and it suffices if the instruments for tracheotomy 
are at hand. 
(1) Schabert, in 1779, propounded the oldest method, viz. ? 
hyovertobrotomy, where the pouch is penetrated through 
the stylo-maxillaris muscle. The hair in front of the wing 
of the atlas for an area of 2 to 4 inches is shaved; an 
incision is made through the skin about f of an inch in 
front of the anterior border of the wing, and parallel with 
it. Just in front of the wing lies the auricular nerve, arising from the 
second cervical nerve, which must be avoided. 
Separating the subcutis by a few light strokes, the parotid, recognised 
Fig. 64.— 
Gunther’s 
catheter. 
