Page 624 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Respir atory system: 3.2 Surgical conditions of the respir atory tr act 599

VetBooks.ir about 5 cm caudal to the nostril. It can be easily pal- 3.11
pated via the false nostril and is non-painful, seldom
causes any respiratory obstruction and is of cosmetic
significance only.

Differential diagnosis
Possibly skin tumours such as sarcoid but the clinical
presentation is quite typical.

Diagnosis
Clinical examination and via centesis aspiration of
grey, greasy contents.

Management Fig. 3.11 Aspiration of grey greasy sebaceous
Atheroma are simply and effectively managed by material from the cyst prior to injection of formalin.
injection with 10% formalin. In the standing, sedated
horse the thick sebaceous contents are aspirated and
following this a similar volume of formalin–saline out, using a laryngeal or ventricular ‘Hobday’ burr.
is injected – usually about 5 ml (Fig. 3.11). There Surgical removal is seldom necessary.
is swelling for 24 hours and then the cyst gradually
regresses over 7 days. Alternatively, a stab incision Prognosis
can be made under local anaesthesia, via the false Prognosis is excellent and recurrence is very rare fol-
nostril into the cyst. The cyst lining is then reamed lowing complete destruction of the secretory lining.

NASAL PASSAGES

WRY NOSE 3.12

Definition/overview
A complex congenital deformity of the nose with
shortening and deviation of maxilla, premaxilla,
nasal bone, vomer and nasal septum. Occasionally
there is a milder mandibular deformity and/or
dorsoventral deviation.

Aetiology/pathophysiology
Wry nose is of unknown aetiology but may be
genetic. It may be more frequent in the Arabian and
draught breeds, and possibly in primiparous mares,
but the true incidence is not known. Some cases may
be associated with contracted foal syndrome and
may therefore be seen following dystocia.

Clinical presentation
Visible deviation of the maxilla is present, often asso- Fig. 3.12 Dorsopalmar radiograph of a wry nose
ciated with respiratory stridor at rest, particularly in a foal. Note the markedly deviated upper jaw.
in moderately or severely affected foals (Fig. 3.12 (Photo courtesy Graham Munroe)