Page 63 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

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

Following diagnosis of nasal aspergillosis, topical anti- 100 ml of polyethylene glycol 200 is infused into the nasal
fungal treatment is indicated. Systemic antifungal therapy cavity through the infusion catheters. When fluid is noted
VetBooks.ir cacy and is not recommended as the sole form of treat- catheters are occluded and the dog is rotated to each
within the lumen of the pharyngeal catheter, the infusion
requires prolonged treatment (2–3 months), has poor effi-
lateral position for 15 minutes and left in dorsal and ventral
ment (Peeters et al., 2005; Sissener et al., 2006; Billen
et al., 2010). Systemic therapy has been used as part of
of 1 hour. After treatment, the catheters are removed, and
a combination protocol for cases that do not respond to recumbency for 15 minutes each, for a total infusion time
topical treatment alone. Topical antifungal therapy is con- the pharynx is suctioned to remove fluid and debris.
sidered the treatment of choice for nasal aspergillosis. The reported success rate of this procedure after one
Some authors recommend meticulous debridement of treatment is 86% (Mathews et al., 1998; Davidson et al.,
fungal plaques, fungal balls and necrotic tissue prior to 2005), but large studies on long-term outcome using this
topical antifungal therapy (Zonderland et al., 2002). Topical technique are not available. Topical infusion of clotrimazole
medication can be instilled into the nasal cavity through an has been described in cats, with success (Tomsa et al.,
infusion catheter placed surgically into the frontal sinus or 2003), although it has been suggested that topical enil-
via catheters passed through the nares (Mathews et al., conazole (either 1% or 2%) is more efficacious than clotri-
1996, 1998; Davidson et al., 2005). Clotrimazole cream mazole (Zonderland et al., 2002). Enilconazole is not
(20 g) instilled into each frontal sinus using a 10 Fr urinary available in the USA, however.
catheter placed through a 3.2 mm Steinmann pin hole was Follow-up rhinoscopy is strongly recommended 3–6
shown to have excellent filling of the frontal sinuses and weeks after infusion to assess the response to therapy.
nasal cavity, based on CT scans (Burrow et al., 2013). The procedure may need to be repeated more than once
Current evidence suggests that the two methods of depending on clinical signs and the results of follow-up
treatment have equal efficacy, although the non-invasive rhinoscopy. Further improvements in topical treatment
technique has fewer complications (Richardson and consist of the use of viscous antifungal creams for applica-
Mathews, 1995; Mathews et al., 1998). A non-invasive tion in the frontal sinuses. Combined trephination, a short
topical antifungal nasal infusion must be done under clotrimazole (1%) soak and application of clotrimazole
general anaesthesia (Figure 4.11). The patient is intubated (1%) cream to the frontal sinuses (10–20 g per sinus) led to
and the pharynx is packed with moist gauze. A 24 Fr Foley a great reduction in the duration of the procedure and
catheter is placed through the mouth and over the soft pal- hos pitalization and good success rates (50–86% clinical
ate so that the tip is facing rostrally. The balloon is inflated cure) (Sissener et al., 2006; Sharman et al., 2010). Depot
to occlude the nasopharynx. The caudal nasopharynx is therapy with bifonazole cream applied via per-endoscopic
subsequently further packed with gauze. Two 10 Fr infu- frontal sinus catheters has also been described and, in
sion catheters are placed through the nostrils into the combination with debridement and enilconazole infusion,
dorsal nasal meatus to the level of the medial canthus or resulted in nearly 60% clinical cure (Billen et al., 2010).
guided rhinoscopically into the frontal sinus. A 12 Fr Foley A report of successful treatment of mycotic rhinitis
catheter is inserted into each nostril and the balloons are in three dogs was published that involved extensive surgical
inflated to occlude the nares. Alternatively, the distal end debridement and open wound management using a topical
of an 18 Fr Foley catheter is cut with scissors, after which povidone–iodine dressing (Moore, 2003). The disadvan-
a urinary catheter is passed through the Foley catheter, to tages of surgical rhinotomy include increased time, cost and
decrease leakage from the nostril site as a result of having morbidity, as well as disruption of the local blood supply,
two round catheters in place. The dog is put into dorsal which may impede healing. There is no proven increase in
recumbency, and 1 g of clotrimazole (some formulations of efficacy with surgical rhinotomy and open debridement for
clotrimazole contain alcohol; these should be avoided) in fungal disease (White, 2006).
Placement of
4.11 catheters for nasal
Endotracheal and sinus infusion with
tube clotrimazole. Endotracheal
intubation ith cu ng and
Hard palate packing the caudal pharyngeal
area are mandatory to prevent
aspiration of clotrimazole.
Soft palate
Pharyngeal
sponges

Nasopharyngeal Foley
catheter

Infusion catheter

Cribiform palate Rostral nasal
Foley catheter
Medial frontal sinus
Rostral frontal sinus
Lateral frontal sinus

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