Adriaan Kitshoff

A retrospective study of 109 dogs with mandibular fractures

OBJECTIVE To determine patient factors and fracture morphology of dogs presented with mandibular fractures to a small animal referral centre in South Africa. METHODS Patient data on age, sex, breed and aetiology of dogs with mandibular fractures were recorded. The fractures were classified according to the anatomical location, displacement, fracture type, fracture line direction, periodontal pathology, and whether there were teeth in the fracture line or not by evaluation of preoperative radiographs. Clinical observations indicated whether these fractures were open or closed. RESULTS In total, 109 dogs with 135 mandibular fractures were included in the study. Small breed dogs and dogs less than eight months of age predominated (102/109). Dog fights were the most common aetiology in this study (68/109). The molar region was the most commonly affected region (56/135). Evaluation of the radiographs revealed that transverse (73/135), relatively unstable (116/135), and displaced (112/135) fractures were the most common. The majority of fractures involved teeth in the fracture line (100/135), with the first molar frequently involved (54/135). The majority of fractures were open (104/135). CLINICAL SIGNIFICANCE The results obtained from this study may be used to guide patient and fracture morphology selection in biomechanical studies of mandibular fracture repair techniques. Screening of this patient population may inspire the search for new treatment options for mandibular fracture repair in South Africa.

Laryngeal paralysis in dogs: An update on recent knowledge

Laryngeal paralysis is the effect of an inability to abduct the arytenoid cartilages during inspiration, resulting in respiratory signs consistent with partial airway obstruction. The aetiology of the disease can be congenital (hereditary laryngeal paralysis or congenital polyneuropathy), or acquired (trauma, neoplasia, polyneuropathy, endocrinopathy). The most common form of acquired laryngeal paralysis (LP) is typically seen in old, large breed dogs and is a clinical manifestation of a generalised peripheral polyneuropathy recently referred to as geriatric onset laryngeal paralysis polyneuropathy. Diagnosing LP based on clinical signs, breed and history has a very high sensitivity (90%) and can be confirmed bylaryngeal inspection. Prognosis after surgical correction depends on the aetiology: traumatic cases have a good prognosis, whereas tumour-induced or polyneuropathy-induced LP has a guarded prognosis. Acquired idiopathic LP is a slow progressive disease, with dogs reaching median survival times of 3-5 years after surgical correction.

The comparative biomechanics of the reinforced interdental crossover and the Stout loop composite splints for mandibular fracture repair in dogs

OBJECTIVES To describe a new technique, the reinforced interdental crossover composite splint (RIC), for transverse mandibular fracture repair in dogs. This technique was compared biomechanically with the established reinforced interdental Stout loop composite splint (RIS) technique. METHODS Six pairs of mandibles from young adult small breed dogs were used for the study. Osteotomies were created in a standardized fashion and fixed with either RIC or RIS. All composite splint constructs were tested biomechanically with a cantilever bending force, using a single column testing machine at a rate of 2 mm/min. The time of application, amount of composite used, ultimate force, stiffness, total displacement, and total energy absorbed during displacement of the rostral mandibular segment were calculated and compared between the two groups. RESULTS No significant difference was found when comparing the time of application of the RIC and the RIS techniques. All implants failed by either composite resin fracture over the region of the osteotomy or by fracture between the first and second molar followed by detachment of the resin from the lingual enamel surface of the first molar. Differences between the RIC and RIS in force (80.5 N ± 40.3 and 51.8 N ± 27.4. respectively) and stiffness (16.2 N/mm ± 4.4 and 10.1 N/mm ± 4.1 respectively) were significant (p = 0.03). However differences between the two techniques in displacement and total energy absorbed were not significant. CLINICAL SIGNIFICANCE In experimentally fractured mandibles of young adult dogs there is evidence that RIC is biomechanically similar to RIS.

Negative pressure wound therapy using polyvinyl alcohol foam to bolster full-thickness mesh skin grafts in dogs

Objective: To report the use of negative pressure wound therapy (NPWT) with polyvinyl alcohol (PVA) foam to bolster full‐thickness mesh skin grafts in dogs. Study Design: Retrospective case series. Animals: Client‐owned dogs (n = 8). Material and Methods: Full‐thickness mesh skin graft was directly covered with PVA foam. NPWT was maintained for 5 days (in 1 or 2 cycles). Grafts were evaluated on days 2, 5, 10, 15, and 30 for graft appearance and graft take, granulation tissue formation, and complications. Results: Firm attachment of the graft to the recipient bed was accomplished in 7 dogs with granulation tissue quickly filling the mesh holes, and graft take considered excellent. One dog had bandage complications after cessation of the NPWT, causing partial graft loss. The PVA foam did not adhere to the graft or damage the surrounding skin. Conclusion: The application of NPWT with a PVA foam after full‐thickness mesh skin grafting in dogs provides an effective method for securing skin grafts, with good graft acceptance. PVA foam can be used as a primary dressing for skin grafts, obviating the need for other interposing materials to protect the graft and the surrounding skin.

Comparison of a 5-mm and 10-mm vessel sealing device in an open ovariectomy model in dogs

The objectives of this study were to compare (1) the extent of thermal damage and (2) the time between the 5-mm LigaSure V (LS5) and 10-mm LigaSure Atlas (LS10) vessel sealing devices (VSD) when performing open ovariectomy in dogs. A prospective, randomised, clinical trial was performed in 40 client-owned sexually entire female dogs. In each dog, one ovary was randomly assigned to be surgically removed using LS5 and the contralateral using LS10. The depth of thermal spread, measured on histopathological preparations, was significantly larger for LS10 (LS10 1.35±0.23 mm v LS5 0.82±0.10 mm; P<0.001). Mean ovariectomy time was significantly faster when using LS10 (LS5 2.58±1.32 minutes v LS10 2.07±1.27 minutes; P=0.008). Bodyweight was positively correlated with the time required for ovariectomy using LS5 (P=0.004), but no such correlation was present for LS10 (P=0.611). In conclusion, during open ovariectomy using VSD, LS10 causes significantly more thermal spread but surgical time is shorter compared with LS5. When using LS5, the ovariectomy time increases with increasing bodyweight.

Transdiaphragmatic pericardiectomy in dogs

In patients with recurrent pericardial effusions, pericardiectomy is indicated. The purpose of this study was to describe a transdiaphragmatic approach for subtotal pericardiectomy in dogs and to evaluate its feasibility. In total, 20 canine cadavers weighing less than 10 kg (group S) and 20 weighing more than 20 kg (group L) were used. Within each group, half underwent a subphrenic pericardiectomy via an intercostal approach and half via a transdiaphragmatic approach. For each approach and within each weight group, the percentage of resected pericardium was calculated and compared. Additionally, a case series of nine consecutive client-owned dogs that underwent a transdiaphragmatic pericardiectomy for pericardial effusion was reported. Exposure of pericardium and associated phrenic nerves was excellent in cadavers and clinical patients. In group S, the percentage of resected pericardium was not significantly different between the two approaches. In group L, on the other hand, the percentage of resected pericardium was lower with the transdiaphragmatic approach compared with the intercostal approach (P=0.001). In the clinical patients, no intraoperative complications were encountered and no recurrence of pericardial effusion was seen. Subtotal pericardiectomy via a transdiaphragmatic approach is straightforward and a safe surgical procedure to obtain permanent pericardial drainage in small and large breed dogs.

Transdiaphragmatic Approach to Attenuate Porto‐Azygos Shunts Inserting in the Thorax

OBJECTIVE To describe the surgical technique and document the application of a transdiaphragmatic approach to attenuate porto-azygos shunts inserting in the thoracic section of the azygos vein. STUDY DESIGN Cadaveric study and prospective case series. ANIMALS Canine cadavers (n=6) and client-owned dogs with porto-azygos shunts inserting in the thoracic section of the azygos vein (n=9). METHODS In the cadavers, the azygos vein was filled with aqueous latex. Landmarks were established for creating a safe transdiaphragmatic approach to the caudal intrathoracic portion of the azygos vein. In the clinical cases, porto-azygos communication was diagnosed by trans-splenic portal scintigraphy. All shunts were attenuated close to their insertion site via ventral midline celiotomy and a transdiaphragmatic approach to the shunt. Perioperative complications were recorded. RESULTS A 3-5 cm incision, 0.5-1 cm ventral and lateral to the level of the aortic hiatus, was made in the pars lumbalis part of the diaphragm. Stay sutures at both sides of the diaphragmatic incision were placed to open up the incision and a retractor was used to push the esophagus away from the aorta. Intrathoracic insertion of the shunt was confirmed intraoperative. Exposure of the shunt insertion site at the azygos vein was excellent in all clinical cases. No intraoperative or postoperative complications were encountered. CONCLUSION If thoracic attenuation of a porto-azygos shunt is considered, a transdiaphragmatic approach exposes the insertion site for shunt attenuation. This approach is straightforward, without unnecessary abdominal organ manipulation, and since attenuates at the insertion, avoids missing additional contributing branches.

Cutaneous adverse drug reaction in a dog associated with imepitoin

BACKGROUND The macroscopic appearance of cutaneous adverse drug reactions can be similar to a plethora of skin diseases and in particular may resemble autoimmune and immune-mediated disorders. The reaction can occur after single or multiple administrations, with the latter varying in durations of up to years of treatment. These reactions are mostly self-limiting with cessation of the offending drug. OBJECTIVES To report a cutaneous adverse drug reaction associated with chronic administration of imepitoin. CASE REPORT A 4-year-old, Jack Russell terrier dog was presented with progressive skin lesions of 1-week duration. The dog had a 6 month history of idiopathic epilepsy treated with imepitoin for the previous 5 months. Imepitoin is an anti-epileptic drug that acts as a low-affinity partial agonist of the benzodiazepine site at the GABAA receptor. The dosage of imepitoin was increased from 20 mg/kg twice daily to 30 mg/kg twice daily, 3 days before the onset of skin lesions, due to uncontrolled seizures. [Correction added on 15 February 2016 after first online publication: In the preceding sentence, the dosage of imepitoin was previously incorrect and has been amended in this current version.] Dermatological examination revealed erythema and exfoliation at the mucocutaneous junctions of the lips, lip folds, philtrum, ears, axillae and the ventral abdomen. Small erosions and depigmentation were visible on the oral mucosa, lip folds and philtrum. Histopathology was supportive of a lupoid drug reaction. Complete resolution of skin lesions was seen after discontinuation of imepitoin and low dose of prednisolone during a period of 4 weeks. No recrudescence of skin lesions was observed during a 6 month follow-up period. CONCLUSION AND CLINICAL IMPORTANCE Imepitoin may result in cutaneous adverse drug reactions in dogs.

Intralaryngeal thyroarytaenoid lateralisation using the Fast-Fix 360 system: a canine cadaveric study

Introduction Laryngeal paralysis is a condition in which failure of arytaenoid abduction results in a reduced rima glottidis cross-sectional area. The most commonly performed surgical techniques rely on unilateral abduction of the arytaenoid, requiring a lateral or ventral surgical approach to the larynx. Aims and objectives The aim of the study was to investigate a novel minimally invasive intralaryngeal thyroarytaenoid lateralisation technique, using the Fast-Fix 360 meniscal repair system. Materials and methods Larynges were harvested from large breed canine cadavers. With the aid of Kirschner wires placed between the centre of the vocal process and the centre of an imaginary line between the cranial thyroid fissure and the cricothyroid articulation, the mean insertion angle was calculated. Results The Fast-Fix 360 delivery needle inserted intralaryngeally (n=10), according to a simplified insertion angle (70°), resulted in thyroid penetration (>2.5 mm from margin) in all patients. The Fast-Fix was applied unilaterally at 70° with the first toggle fired on the lateral aspect of the thyroid cartilage and inside the laryngeal cavity on retraction. The suture was tightened. Preprocedural (61.06±9.21 mm2) and postprocedural (138.37±26.12 mm2) rima glottidis cross-sectional area was significantly different (P<0.0001). The mean percentage increase in rima glottidis cross-sectional area was 125.96 per cent (±16.54 per cent). Conclusion Intralaryngeal thyroarytaenoid laterlisation using the Fast-Fix 360 meniscal repair system ex vivo increased the rima glottidis cross-sectional area significantly.

Biodistribution and tolerance of intravenous iodine-131-labelled hypericin in healthy dogs

Hypericin (Hyp) is a necrosis-avid compound that can be efficiently labelled with radioiodine for both diagnostic and therapeutic purposes. Before 131 I-Hyp can be considered as a clinically useful drug in a combination therapy for canine cancer patients, evaluation of its toxicity is necessary. The aim of this study was to investigate the biodistribution and tolerance of a single dose administration of 131 I-Hyp. Three healthy dogs were included. 131 I-Hyp at a dose of 0.2 mg/kg and an activity of 185 MBq was intravenously injected. The effects on physical, haematological and biochemical parameters were characterized and the biodistribution and elimination pattern, the effective half-life and dose rate were assessed. Drug-related adverse events were limited to mild gastrointestinal signs, resolving within 48 hours. No significant differences were found in blood haematology and serum biochemistry before and after treatment. Following administration, highest percentage of injected dose (%ID ± SD) was found in the liver (5.5 ± 0.33), the lungs (4.17 ± 0.14) and the heart (3.11 ± 0.78). After 24 hours, highest %ID was found in colon (4.25 ± 1.45) and liver (3.45 ± 0.60). Clearance from all organs was effective within 7 days. Effective half-life was established at 80 hours, and the dose rate fell below <20 μSv/h at 1 m within 1 day. The current study reveals that single dose treatment with 131 I-Hyp at the described dose is well tolerated by healthy dogs and supports the use of radioiodinated hypericin in a combination therapy for canine cancer patients.