Page 79 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery

Otic and nasopharyngeal Histo ogical or cytological evaluation of the mass should
l
be performed to rule out malignant neoplastic conditions
VetBooks.ir polyps such as squamous cell carcinoma and lymphoma. Bulla
radio graphy or CT may be recommended in cats with
Cats
suspected inflammatory polyps that cannot be visualized
Otic and nasopharyngeal polyps are benign masses that
to evaluate the size and extent of polyps prior to
probably originate from the lining of the middle ear in or palpated via otoscopy or nasopharyngeal evaluation,
cats – they have also been presumed to originate from the attempted removal by traction avulsion or ventral bulla
osteotomy, or in older cats to evaluate for changes more
lining of the auditory (Eustachian) tube, but it is not
clear whether this is a site of origin or whether some consistent with neoplasia (e.g. invasion or lysis of the
tympanic bulla).
polyps simply extend through the auditory tube from
The ear canal may need to be gently cleansed of exu-
the middle ear to the nasopharynx. Their aetiology is dates under heavy sedation or anaesthesia before a polyp
unknown, although they are thought to be a response to
inflam mation, since their histological structure is that of is evident. Otic polyps usually do not extend externally
beyond the horizontal canal. In some cases the tympanic
inflammatory tissue.
membrane appears reddened or bulges outward if the
disease is limited to the middle ear. In these cases, bulla
• Ear polyps are red, smooth, round to oblong masses
that may fill the horizontal ear cavity but do not adhere radiographs, or ideally CT, are typically necessary to
confirm the presence of the inflammatory polyp behind
to its surface (Figure 5.7).
• Nasopharyngeal polyps are usually oblong and pinkish the tympanic membrane.
Nasopharyngeal polyps can be seen in anaesthetized
white; they can become inflamed or ulcerated with
trauma. Although not readily visible on oral cats by retracting the soft palate rostrally with a spay
hook or stay sutures. On survey radiographs they are
examination, they tend to displace the soft palate
ventrally as they grow. visible as a soft tissue density within the nasopharynx. CT
findings of nasopharyngeal polyps may include a soft
tissue density mass extending from the nasopharynx
Histologically, inflammatory polyps are composed of
well vascularized fibrous connective tissue covered by through the auditory tube to the tympanic bulla with an
stratified squamous or columnar epithelium. Inflammatory associated stalk-like structure, complete or partial filling
of the dorsal or ventral portions of the tympanic bulla by
cells – primarily lymphocytes, plasma cells and macro-
phages – are present within the stroma and are especially soft tissue, and expansion of the tympanic bulla with
sclerosis of the bulla wall (Oliviera et al., 2012).
dense in the submucosal areas of the tissue.
Dogs
Polypoid hyperplasia of the ear canal occurs commonly
in dogs with chronic OE and represents focal areas of
epidermal hyperplasia, inflammatory cell infiltration and
glandular hyperplasia. Inflammatory polyps extending
through the auditory tube to the nasopharynx have been
rarely described in dogs. Similarly, inflammatory polyps
origin ating within the tympanic bulla and extending
into the external ear canal have also been rarely reported
in dogs (Pratschke, 2003). In one report of five dogs,
middle ear inflammatory polyps were composed of a
fibrovascular stroma, multifocally infiltrated by inflam-
matory cells, and an overlying stratified squamous
epithelium (Pratschke, 2003).
Aural, or otic, polyp extending through the tympanic
5.7
membrane into the horizontal canal of a cat.
Surgical treatment
Clinical signs Otic polyps
Most cats with clinical signs of polyps present as young Otic polyps may be removed from the ear canal by
adults, although polyps have also been reported in older traction, and removal by traction avulsion is frequently
cats. Cats with inflammatory polyps extending to the ear the initial treatment of choice in cases in which the polyp
canal exhibit signs of OE (head shaking, pawing at the may be accessed via the ear canal. Bulla radiographs or
ear) or otic discharge. Signs of OM or OI (e.g. Horner’s CT can be helpful to evaluate the size and extent of otic
syndrome, head tilt, ataxia or nystagmus) are occasion- polyps prior to removal by traction avulsion. Removal by
ally seen. traction may be performed using tissue forceps, mosquito
Cats with nasopharyngeal polyps may present with haemostats or a polypectomy snare. Polypectomy snares
nasal discharge, sneezing, stertorous or laboured breath- that insert through the working port of a fibreoptic
ing, dysphagia, gagging or voice change; occasionally otoscope are particularly helpful as they allow direct visu-
they will also have OE or Horner’s syndrome. alization of the polyp as the snare is placed. A perendo-
scopic transtympanic membrane traction technique has
also been described, which combines removal of the otic
Diagnosis polyp via traction with curetting of the dorsolateral and/or
The diagnosis of inflammatory polyps is made through ventromedial compartments of the tympanic bulla (Greci
otoscopic or nasopharyngeal evaluation and biopsy. et al., 2014).

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