LARYNGOTOMY. 
205 
a soft bottle-brush, or a sponge carefully fastened to a wire. • 1 
implements may without danger be passed as far as the division o ie 
trachea. The tampon-canula may then be placed m position anc 
moderately inflated, that is to say, until the balloon fills the lumen of 
the trachea without exercising much pressure on the mucous membrane, 
which might produce necrosis. Another pattern is Hahn s tampon 
canula, which carries a sponge tent. A substitute may be improvise 
by wrapping Barthelemy’s canula with tow, jute, or sponge, such sub¬ 
stances being carefully secured with string or thread, so that they shall 
not become loose and fall into the trachea. 
(2) Proliferation and thickening of the mucous membrane wi 
narrowing of the lumen of the trachea (tracheal stenosis). Sclerotic 
inflammations occasionally occur in the skin and the soft tissues lying 
beneath, and usually follow cellulitis. Proliferation producing tracheal 
stenosis results from faulty formation of the canula, from its being too 
heavy, badly made, or not fitting the form of the neck. The canula 
cannot fit well if it be too long, too narrow, too little, or too much ben , 
or if the opening in the trachea be too large. A pronounced tendency 
to such growths often exists in heavy horses, and though the canu a 
is perfect in every respect, the contraction recurs after each operation. 
Such stenosis gradually renders the introduction of the tube more and 
more difficult, and finally impossible. The tracheal opening mus len 
be increased, a procedure sometimes rendered-difficult by ossification of 
the newly-formed materials. Where there is room, a second opening 
may be made lower down. In view of such a contingency, tiac leo omj, 
especially in young horses, should be performed in the upper third of 
the neck. 
(6.) LARYNGOTOMY. LARYNGO-FISSURE. 
Section of the larynx in man has lately been much employed, par¬ 
ticularly for the removal of tumours. As already stated, sue l grew s 
in the krynx are rare in animals. But the operation lias been practised 
on horses in hemiplegia of the larynx, otherwise termed roaring, 
K. Gunther, who made the first experiments, hesitated to divide 
cricoid cartilage, because he feared stenosis, and therefore operated lorn 
the trachea. Stockfleth later recommended dividing the cricoid cartilage, 
thus introducing larnygotomy into veterinary practice. I hyroidotomy 
and cricotomy are now distinctive terms, designating respectively division 
in the median line of the thyroid and cricoid cartilages. Where re 
upper rings of the trachea are also divided, the operation is styled cnco- 
tracheotomy; while the division of the cricoid and thyroid cartrlageB, 
together with the connecting crico-tliyroid ligament, is entitled cuco- 
thyroidotomy. 
