A second mode of operating is by external incision. For this purpose are wanted scissors, knife, artery forceps, iron probe bent in the form of the letter S, and a tape. The horse having been thrown and fastened and the head extended, the hair is removed from a surface in front of the prominent border of the first bone of the neck, and an incision made between this border and the parotid gland. The incision is made immediately beneath a tendon which may be felt as a flattened cord crossing the border of the bone in its upper third, and it should be carried downward one and a half inches parallel to the margin of the bone. In this preliminary stage the operator has to carefully avoid injury to the parotid gland and the posterior auricular artery and vein. The skin and fascia having been divided the index finger of the left hand is pushed inward and forward until the prominent angle of the large cornu of the hyoid bone is felt, together with the muscle (stylo-hyoid) inserted into this bone above the angle referred to. The next step is important since crossing on the inner side of this muscle and bone at their point of union is the (internal carotid) artery which becomes subsequently enveloped in a fold of the membranous wall of the guttural pouch. The slightest variation in the position of the artery may here prove fatal unless the greatest caution is used. With the knife guarded by the index finger of the right hand the muscle is cut through from behind forward and the pulsation of the artery felt for beneath. Avoiding its position the knife, with its cutting edge turned forward and its point directed toward the horse’s nose, is pushed through the walls of the sac. The curved prob is now introduced and carried downward until it is felt beneath the skin just behind the angle of the lower jaw. This may be safely cut down upon with the knife as important parts (vessels and nerves) have been turned aside by its pressure. A tape attached to the prob is now drawn through the pouch and retained by a knot on each end. Tepid water must be injected through the lower orifice daily for three weeks, astringent antiseptic injections thrown in occasionally and the horse fed from the ground. At the end of this period the tape may be removed, and the wounds allowed to heal. During the course of treatment it is always advisable to change the tape several times by cutting the knot off one end of the old one, stitching the new one to it and drawing it through.
Puncture of the pouch at its lower part is a very simple operation when the accumulation of pus is abundant and chronic. The distended pouch gravitates downward largely separating the parotid from the deeper vessels and nerves, and finally fluctuates toward the lower end of the gland. In extreme cases it even opens and discharges. When fluctuation can be felt the sac may be incised with a bistoury or abscess knife and treated like a common sore. Opening with a pointed or olive-shaped cautery has the advantage of checking hæmorrhage and securing more perfect drainage. When there is no fluctuation the incision must be made just beneath the lower border of the parotid, the parotidoauricularis being first cut through, then the gland dissected from the deeper parts when the distended sac can usually be felt and opened. If not felt at once it can easily be reached by a careful dissection upward through the loose subparotidean connective tissue, with the finger nail or handle of the scalpel. A free opening may be made and the wound injected daily with a weak antiseptic solution.
ABSCESS OF THE FALSE NOSTRIL.
In young horses as the result of injury from the bridle or severe coryza, a circumscribed swelling sometimes appears on the outer flap of the nostril, at first firm, hot and tender, with a surrounding pasty infiltration, then forming into a tense elastic ovoid mass, the size of a pigeon’s or chicken’s egg. It may become chronic and remain for an indefinite period comparatively insensible to touch and only slightly interfering with the movements of the nostrils. As soon as the elastic tension betrays the presence of pus it should be evacuated by a free incision made from inside the nostrils and the wound plugged with medicated tow and allowed to heal by granulation.
NEOPLASMS IN THE HORSE’S NOSE.
Nasal fibrous polypus, connection, form, size, bony distortion, obstructed breathing, abrasion, ulceration, sloughing, submucous polypus, structure, degeneration. Symptoms, sneezing, snuffling, discharge, palpation, bony swelling, tenderness. Treatment, forceps, hook, ecraseur, knife, saw. Actinomycosis. Sarcoma, Carcinoma. Consistency, structure, fœtor, glandular swelling. Treatment. Recurrence. Fatty tumors. Bony tumors: cancellated or compact tissue, localized or extended. Cysts. Strongyli. Angioma. Varicosity. Color, obstruction to breathing, hæmorrhage, cicatrization.
These are essentially surgical diseases yet as they induce Chronic Catarrh they may be profitably noticed here.
I. Fibrous Nasal Polypus. These are connected to the mucosa by a pedicle or broad base, and vary in size from a pea to a mass which fills the entire nasal chamber, projects from the nostrils and presses outward the septum and facial bones. At times they weigh one or more pounds. They may cause whistling or rattling in breathing, or may completely obstruct the passage of air on the affected side. In time they may cause bulging or even attenuation and perforation of the bony walls, projecting through the hard palate or on the face. Sometimes the surface becomes the seat of granulation, ulceration, or sloughing, causing more or less fœtor. The large polypi make their main growth forward and backward, moulding themselves to the form of the chamber, and displacing the turbinated bones. They commence to grow under the mucous membrane and as they grow and become more loosely attached they carry this as an outer covering and pedicle. When incised they show a structure of interlacing bundles of fibres, with cell elements more or less abundant, according to the rapidity of growth. Gravitz found amyloid degeneration of the walls of the blood vessels and mucous follicles and of the fibres.
Symptoms are difficult breathing, snuffling, a smaller current of air on the affected side, or none, sneezing, a watery, purulent, bloody, or fœtid discharge, and the appearance of the polypus when the nasal chamber is examined in a good light. If beyond reach of vision the polypus may often be felt by the finger. Care must be taken not to mistake the red, angry surface of the turbinated bones in Catarrh for a polypus. If beyond the reach of the finger, the flat sound on percussion of the nasal and frontal bones on the affected side, and the persistently diminished flow of air may serve for diagnosis. Tenderness shown on percussion is common to this and abscess of the sinuses.
Treatment. The horse having been cast with the diseased side uppermost and the head turned to the light, the tumor is seized with the fingers, the forceps, or hook, and drawn gently outward. The chain of the ecraseur may be passed over it and slowly tightened upon the pedicle until it is cut through. This will usually obviate any laceration of the turbinated bones and consequent bleeding. In case of serious hæmorrhage check by cold water, ice, the actual cautery, or by plugging. Polypi with a broad base may be removed with a prob-pointed knife, curved on the flat, and furnished with a long handle. The mass is seized with a vulsella and detachment made by passing the knife with the concave side toward the tumor. In cases where the tumor cannot be seen or reached some have resorted to slitting up the outer wall of the nostril as far as the angle of union of the nasal and maxillary bones, care being taken to make the incision outside the upper end of the cartilage of the ala nasi. If too high to be satisfactorily reached in this way the nasal or frontal bone may be trephined over the body of the tumor as indicated by the flatness on percussion, and the operation performed through the opening thus made.