8 Veterinary Times

Advanced techniquesAdvanced imaging in the pre-operative period, such as CT or MRI, confers several advan-

tages over a simple, exploratory approach. It helps confi rm the diagnosis and identify tracts to, and from, the palpable abscess

cavity. Often, the foreign body is readily identifi able and precise “coordinates” can be given to the surgeon, relative to palpable landmarks such as the larynx, trachea and angle of mandible (Figures 4 and 5). Any displaced vasculature

can also be identifi ed and the surgical approach planned, to avoid unnecessary trauma to the important head and neck neurovasculature. A true nidus removal surgery can then be performed through a relatively limited dissection (Figure 6). Comparison between foreign material removed and its pre-operative appearance on imag-ing helps increase confi dence that the entire foreign body has been removed (Figure 7).

After adequate exploration, representative biopsies are taken for tissue culture and histopathology. The majority of the abscess wall is extracted (if safe to do so) to remove as much particulate foreign mate-rial as possible from the wound. The whole wound is then thor-oughly lavaged (Figure 8) and closed routinely. Dead space can be managed with appropri-

TIM CHARLESWORTH graduated from the University of Cambridge in 2001 and joined Eastcott Veterinary Hospital in 2003. He gained the RCVS Certifi cate in Small Animal Surgery in 2006, followed by the RCVS Diploma in Small Animal Surgery (Soft Tissue) in 2012. Tim is an RCVS-recognised specialist in small animal surgery (soft tissue) and heads the soft tissue team at Eastcott Referrals, Swindon.

ate use of drains. Patients can be discharged, once comfortable, and usually placed on a course of broad-spectrum antibiotics (until results of the tissue culture are available) in addition to pro-vision of appropriate analgesia.

Although the long-term prognosis for dogs with appro-priately treated oropharyngeal injuries is usually good, clients should be warned of possible cervical abscess development after acute oropharyngeal per-forations, or chronic cervical abscess recurrence after explo-ration. Both can be attributed to persistent residual foreign matter/nidus of infect ion. Advanced imaging modalities are strongly recommended before reoperation in recur-rent cases.

Oesophageal injuryOesophageal penetrations have been associated with a significantly worse prognosis than oropharyngeal penetra-tions. If screening radiographs show evidence of subcuta-neous emphysema and an oesophageal tear is suspected, surgical exploration should be performed via a ventral mid-line approach. Foreign matter is removed, the wound lav-aged and the oesophageal wall gently debrided and sutured. Drains are used to manage ongoing exudate production and gastrotomy tubes should be considered to bypass the healing oesophagus for 10 days, postoperatively. This surgery can be complicated, with a 36

Figure 4. Transverse CT image of a relatively low-density foreign body (arrow) within a fl uid-fi lled pocket, with a contrast enhancing rim (abscess) in the left perilaryngeal region.

Figure 5. Sagittal CT image of the same case as Figure 4. The foreign material (arrow) is clearly visible.

per cent mortality rate recently reported for dogs with acute oesophageal stick penetration (Doran, 2008).

SummaryStick injuries can represent themselves in many ways – from acute, uncomplicated oropharyngea l punctures to oesophageal penetration wounds with a significantly worse prognosis. Prompt inves-tigations will differentiate these two disorders, allowing each to receive appropriate treatment without delay. Chronic stick injuries often require advanced imaging to maximise chances of successfully removing all foreign material trapped within the head and neck tissues.

ReferencesDobromylskyj M J, Dennis R, Lad-low J F, Adams V F (2008). The use of magnetic resonance imaging in the management of pharyngeal penetration injuries in dogs, JSAP 49: 74-79.Doran I P, Wright C A, Hotston-Moore A (2008). Acute oropharyn-geal and esophageal stick injury in 41 dogs, Vet Surg 37: 781-785.Griffi ths L G, Tiruneh R, Sullivan M, Reid S W J (2000). Oropharyngeal penetrating injuries in 50 dogs: a retrospective study, Vet Surg 29: 283-288.Nicholson I, Halfacree Z, What-mough C, Mantis P, Baines S (2008). Computerised tomography as an aid to management of chronic oro-pharyngeal stick injury in the dog, JSAP 49: 451-457.White R A S, Lane J G (1988). Phar-yngeal stick injuries in the dog, JSAP 29: 13-35. �

CLINICAL CANIDAE

� IN THE STICK OF IT – A PLAYFUL PASTIME WITH PERILOUS CONSEQUENCES FOR DOGS – from page 6

Figure 6. Intraoperative view of the same case as Figures 4 and 5. A ventral midline approach has been performed and the abscess cavity containing the foreign body identifi ed within the left perilaryngeal region (patient head is to left).

Figure 8. The abscess cavity is explored and thoroughly lavaged, prior to closure.

Figure 7 (inset). The removed foreign material is of the same shape and size as the foreign material identifi ed on the pre-operative CT.

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