Evaluation of different methods of securing cellophane bands for portosystemic shunt attenuation.

OBJECTIVE: To compare mechanisms of and pressures at failure of 4 methods of securing 2 types of cellophane bands around a vein. STUDY DESIGN: Ex vivo mechanical evaluation. METHODS: Cellophane bands composed of 3 or 4 layers were applied around a cadaveric external jugular vein (EJV) to create 25% or 50% attenuation. These bands were secured with a medium or medium-large polymer locking ligation clip (PLLC), or a medium or medium-large titanium ligation clip (TLC). Sterile saline 0.9% was instilled into the lumen of the EJV until a pressure of 100 mm Hg was reached. Failure mechanism and luminal pressure at failure were compared between groups. RESULTS: Medium clips failed less often than medium-large clips (P < .001) and consistently sustained 100 mm Hg without failing. Three-layer cellophane bands were 4.1 times more likely to fail than 4-layer bands (P = .003, CI 1.6-10.2) and failed at lower pressures (28.32 ± 3.59 mm Hg and 44.81 ± 6.51 mm Hg, respectively, P = .027). Failure rates of the cellophane band constructs did not differ whether secured with PLLC or with TLC (P = .635) or with 25% vs 50% attenuation (P = .780). CONCLUSION: A single medium clip withstood physiological forces and secured a cellophane band at up to 50% attenuation. A 3-layer cellophane band was more likely to fail compared with a 4-layer cellophane band. CLINICAL SIGNIFICANCE: These ex vivo results provide evidence to support the application of a 4-layer cellophane band secured with a single medium PLLC or TLC for portosystemic shunt attenuation. A single medium PLLC should be used to eliminate computed tomography artifacts during postoperative evaluation of shunt closure.

Multi-Center Retrospective Evaluation of Screw and Polymethylmethacrylate Constructs for Atlantoaxial Fixation in Dogs.

OBJECTIVE: To evaluate outcome and adverse events following ventral stabilization of the atlantoaxial (AA) joint in dogs with clinical AA subluxation using screw/polymethymethacrylate (PMMA) constructs in a retrospective, multi-center cohort study. STUDY DESIGN: Historical cohort study. ANIMALS: 35 client-owned dogs. METHODS: Medical records from 3 institutions were reviewed to identify dogs with AA subluxation treated with ventral screw and PMMA constructs. Data on signalment, pre- and postoperative neurologic status, imaging performed, and adverse events were retrieved. Neurologic examination data were abstracted to generate a modified Frankel score at admission, discharge, and re-examination. Telephone interview of owners >180 days postoperative was conducted. RESULTS: Thirty-five dogs with AA subluxation treated with ventral screw/PMMA constructs were included. Most dogs were young (median age 1 year), small breed dogs with acute onset of neurologic signs (median duration 22.5 hours). Most dogs were non-ambulatory at the time of admission (median modified Frankel score 3). Adverse events were identified in 15/35 dogs including 9 dogs with major adverse events. Four dogs required a second surgery due to vertebral canal violation (n = 2) or implant failure (n = 2). Re-examination at 4-6 weeks postoperative reported 15/28 dogs with improved neurologic status and 19/28 dogs were ambulatory. Telephone follow-up was available for 23/35 dogs with 23/23 reported as ambulatory (median follow-up 390 days). CONCLUSIONS: Ventral application of screw and PMMA constructs for AA subluxation, as described here, is associated with clinical improvement in the majority of dog. Major adverse events are infrequent and the technique is considered relatively safe.

Extraction of cheek teeth using a lateral buccotomy approach in 114 horses (1999-2009).

REASON FOR PERFORMING THE STUDY: There are few published data regarding the success rates of cheek tooth (CT) removal by lateral buccotomy in the horse. OBJECTIVES: A retrospective study of 114 horses admitted to 2 private equine referral hospitals over a 10 year period (1999-2009), which underwent CT removal via a lateral buccotomy. METHODS: Hospital records were analysed and details including case details, presenting complaint and results of all diagnostic tests and surgical reports were documented. Information obtained during post operative reassessment was also available for analysis. Long-term follow-up information (>2 months) was obtained for 112 horses. RESULTS: Short-term complications (<2 months) occurred in 24/77 horses (31%) undergoing exodontia of the maxillary CT and 10/37 horses (27%) involving mandibular CT, with the majority arising from partial wound dehiscence and infection following 16 extractions (47%). All healed well by second intention. Other complications included both temporary (n = 6) and permanent (n = 3) facial nerve paralysis, myositis (n = 4) and the inadvertent establishment of an oroantral fistula (n = 4). One myositis case was subjected to euthanasia 24 h post operatively. Five horses had persistent sinusitis following surgery due to dental remnants (n = 2) and excessive packing material (n = 1) found in the sinuses. No inciting cause could be found in the remaining 2 horses. One further horse suffered a fatal cardiac arrest at induction of anaesthesia. Of all horses, 92% operated on had returned to their previous level of work after >2 months with no complications. CONCLUSION: Horses with CT removal by a lateral buccotomy have a reasonable prognosis for long-term outcome. POTENTIAL RELEVANCE: Performing a lateral buccotomy is a justified treatment alternative for the surgical removal of equine CT following unsuccessful attempts by standing oral extraction, offering advantages over alternatives such as retropulsion, endodontic therapy and periapical curettage.

The efficacy of allogeneic mesenchymal precursor cells for the repair of an ovine tibial segmental defect.

INTRODUCTION: Synthetic void-fillers offer an alternative to autograft or allograft bone in the repair of segmental defects. However, the reparative process is delayed as only osteoconductive elements are present. The inclusion of pluripotential cells may resolve this limitation, and the use of allogeneic tissue provides the opportunity for an off-the-shelf remedy. The current study evaluated the utilisation of mesenchymal precursor cells (MPC) for the repair of an ovine critical-size tibial segmental defect. METHODS: Twenty-four, mature female sheep underwent surgery for the creation of a 3 cm tibial diaphyseal defect. In one group of 12 sheep the scaffold was used alone, and in the second group the scaffold was seeded with MPC. The defect was stabilised using a locking intramedullary nail and allowed to heal over a nine-month-period. Outcome assessments of healing included radiology of callus formation, computed tomography, assessment of new-bone volume, mechanical attributes, and histological evaluation of linear bone apposition rate and tissue response. RESULTS: The MPC-treated group displayed a significantly greater level of callus formation and rate of bone apposition in the defect. DISCUSSION: The incorporation of allogeneic MPC to a synthetic void filler stimulated early repair of critical-size diaphyseal segmental defects and holds potential as an off-the-shelf therapy for augmenting bone regeneration.

A case of facial deformity due to bilateral developmental maxillary cheek teeth displacement in an adult horse.

A 7-year-old mare presented with facial deformities associated with oral discomfort and weight loss was found to have bilateral, palatal, developmental displacements of the maxillary 08s, with secondary diastema. Following repulsion of both displaced teeth, the horse regained weight and resumed training. Bony deformities remained visible 9 mo after discharge.

Complications of equine oral surgery.

The vast majority of equine oral procedures are dental-related and, unless great care is taken, almost all such procedures have the potential to cause marked short- or long-term damage to other oral structures. This review of the more common complications of oral surgery begins at the rostral oral cavity with procedures of the incisors, and then moves caudally to deal with complications related to procedures of wolf teeth and cheek teeth, including salivary duct disruption and dental sinusitis. Finally, complications associated with maxillary and mandibular fractures are discussed.

Do different characteristics of two emasculators make a difference in equine castration?

BACKGROUND: The Serra and Reimer emasculators are frequently used in equine orchiectomy. They differ in jaw profile and the mechanism by which they achieve haemostasis. OBJECTIVES: To investigate whether the haemostatic capacities of the Reimer and Serra emasculators in open and closed castration differ, to compare the haemostatic capacities of each emasculator in both open and closed castration, and to assess whether the tensile strength of the parietal tunic in closed castration differs according to whether a Reimer or Serra emasculator is used. STUDY DESIGN: Ex vivo randomised study. METHODS: Eighty equine cadaver testes were randomly assigned to two groups for, respectively, open and closed castration. Each group was divided into two subgroups for castration with a Serra or Reimer castrator, respectively. Testicular artery leaking pressure was measured by dye injection. In closed castration, the tensile strength of the parietal tunic was measured with a tensiometer. RESULTS: In open castration, the Reimer emasculator resisted significantly higher pressure (median: 706.1 mmHg; interquartile range [IQR]: 597.6-735.5 mmHg) than the Serra emasculator (median: 349.4 mmHg; IQR: 261.1-468.9 mmHg) (P<0.001), whereas no difference was found in closed castration (Serra emasculator, median: 382.5 mmHg [IQR: 294.2-568.2 mmHg]; Reimer emasculator, median: 419.2 mmHg [IQR: 294.2-616.0 mmHg]). The Reimer emasculator resisted significantly higher pressure in the open (median: 706.1 mmHg; IQR: 597.6-735.5 mmHg) compared with the closed (median: 419.2 mmHg; IQR: 294.2-616.0 mmHg) technique (P = 0.03). Parietal tunic tensile strength did not differ significantly by emasculator (mean ± s.d.: Serra, 12.65 ± 7.35; Reimer, 17.55 ± 11.76). MAIN LIMITATIONS: Limitations are inherent to the ex vivo study design. Post-surgery implications were investigated only in the short term and no account was taken of tissue inflammation and oedema, which may influence the integrity of the tissue. CONCLUSIONS: These results suggest it may be preferable to use a Reimer emasculator in open castration. In this ex vivo model of closed castration, no differences between the emasculators were observed.

Standing intraoral extractions of cheek teeth aided by partial crown removal in 165 horses (2010-2016).

BACKGROUND: Diseased cheek teeth in horses often require invasive extraction techniques that carry a high rate of complications. Techniques and instrumentation were developed to perform partial crown removal to aid standing intraoral extraction of diseased cheek teeth in horses. OBJECTIVES: To analyse success rates and post-surgical complications in horses undergoing cheek teeth extraction assisted by partial crown removal. STUDY DESIGN: Retrospective cohort study. METHODS: This study included 165 horses with 194 diseased cheek teeth that were extracted orally assisted by partial crown removal between 2010 and 2016. Medical records were analysed, including case details, obtained radiographs, surgical reports and follow-up information. Follow-up information (≥2 months) was obtained for 151 horses (91.5%). There were 95 horses examined post-operatively by the authors and, 16 horses by the referring veterinarian; in 40 horses, post-operative follow up was obtained by informal telephone interviews with the owner. RESULTS: Successful standing intraoral extraction of cheek teeth was obtained in 164/165 horses (99.4%). Twenty-five of these horses (15.2%) required additional intraoral extraction methods to complete the extraction, including minimally invasive transbuccal approach (n = 21) and tooth sectioning (n = 4). There was one (0.6%) horse with intraoral extraction failure that required standing repulsion to complete the extraction. The intraoperative complication of fractured root tips occurred in 11/165 horses (6.7%). Post-operative complications occurred in 6/165 horses (3.6%), including alveolar sequestra (n = 4), mild delay of alveolar healing at 2 months (n = 1), and development of a persistent draining tract secondary to a retained root tip (n = 1). MAIN LIMITATIONS: Specialised instrumentation and additional training in the technique are recommended to perform partial crown removal in horses. CONCLUSION: Horses with cheek teeth extraction by partial crown removal have an excellent prognosis for a positive outcome. The term partial coronectomy is proposed for this technique.

Technical note: reversible re-entrant cannulation of the parotid duct in cattle using a new injection anesthesia regimen.

A new method for reversible reentrant cannulation of the parotid duct in cattle by use of an injectable anesthetic regimen is described. Ruminal contents were removed before anesthesia instead of food deprivation. The parotid duct was dilated by means of a long hemostatic forceps: its jaws were encased in a piece of plastic tube, and the tip was extended by a piece of flexible wire. A polyethylene parotid catheter was inserted into the dilated duct and passed through the cheek. The saliva was re-directed back into the mouth via a silicone tube through another fistula in the cheek. The cannulations were maintained for 3 to 11 wk and two cows were recannulated three to five times in both parotid ducts without problems. No pathological changes of the mouth epithelium were found at slaughter. The rate of flow from the ducts during rest, ruminating, and eating were 5 to 20, 25 to 50, and 40 to 75 mL/min, respectively.

Lateral buccotomy for removal of a supernumerary cheek tooth in a horse.

A 3-year-old female Standardbred was admitted for evaluation of a firm swelling on the right side located rostral to the facial crest and a firm intraoral swelling located rostral to the erupted cheek teeth. Examination of skull radiographs revealed a supernumerary cheek tooth rostral to the erupted third premolar. The supernumerary tooth was removed via lateral buccotomy. The horse did not have complications after surgery and resumed racing. Lateral buccotomy should be considered for removal of rostrally located maxillary or mandibular cheek teeth. Supernumerary cheek teeth can be found in locations in the upper dental arcade, other than caudal to the last molar.

Use of portocaval venografts with ameroid constrictor placement and hepatic lobectomy for treatment of intralobular intrahepatic portocaval shunts in four dogs.

Liver lobectomy for complete attenuation of intrahepatic portosystemic shunts appears to be a safe and effective surgical treatment. When the intrahepatic shunt vessel can be definitively palpated within a liver lobe or its presence confirmed portographically, liver lobectomy represents a technically simple and effective method of complete shunt attenuation. To maintain portal pressure at an acceptable value after lobectomy, an extrahepatic portocaval shunt vessel can be created by use of an external jugular vein graft. A second shunt vessel can be created if portal pressure remains increased after placement of 1 shunt. Gradual and safe attenuation of the shunt vessel is achieved by placement of an ameroid constrictor on the extrahepatic graft at the time of the initial surgery.

Cranioplasty by means of molded polymethylmethacrylate prosthetic reconstruction after radical excision of neoplasms of the skull in two dogs.

Two dogs with osteoma or multilobulated tumor of bone of the skull were treated with large en bloc resections. The resections resulted in exposure of the brain above the horizon line of the remaining calvarium; in 1 dog, the removal of the dorsal orbital rims also exposed both orbits dorsally. Protection of the brain and exposed tissues and restoration of the cosmetic appearance of the skull were attempted by use of molded polymethylmethacrylate prosthetic reconstruction of the calvarium. The technique described involves cranioplasty by use of a preformed molded polymethylmethacrylate implant. Such prosthetic cranioplasty may benefit dogs undergoing radical excision of extensive tumors, and the usefulness and potential complications of its application are discussed.

Feline odontoclastic resorptive lesions an unsolved enigma in veterinary dentistry.

This article presents a comprehensive review of the literature on feline odontoclastic resorptive lesions (FORLs), including etiopathogenesis, prevalence and predisposition, classification, histopathologic appearance, diagnosis, and treatment. Approximately one-third of all domestic cats may develop FORLs during their life span, and the risk of developing FORLs increases with age. Sophisticated dental treatments promise neither cure nor permanent improvement of affected teeth. Extraction is the current treatment of choice. Research on the etiology of FORLs has not been rewarding in recent years, and the causative factors contributing to the development of FORLs are still unknown.

A modified technique for implantation of polypropylene mesh for the repair of external abdominal hernias in horses: a review of 21 cases.

During a 3-year period 21 horses were surgically treated because of large abdominal wall defects. In each case the defect was bridged with a polypropylene mesh, which was placed on the outside of the hernial ring. This was in contrast with the technique for mesh herniorrhaphy generally described in human and veterinary literature, in which the mesh is always implanted on the inside of the hernial ring. One horse was destroyed on the first postoperative day because of postanaesthetic myelomalacia. Surgical repair as described was successful in 18 patients. Recurrence of herniation occurred in two horses. On re-herniorrhaphy a second and larger mesh was successfully implanted.

Surgical cleft soft palate repair in a foal.

An Anglo-Arab foal with bilateral postprandial nasal discharge was diagnosed as having a full-length defect of the soft palate. Surgical repair was attempted using a combination of two surgical approaches. Initially a mandibular symphysiotomy approach was used. The posterior portion of the defect did not heal adequately, so a ventral laryngotomy, bisecting the body of the thyroid cartilage and extending to a pharyngotomy approach, was performed 5 months later. The foal has since matured fully despite a slight unilateral nasal discharge. This case report demonstrates that these two surgical approaches used simultaneously provide surgical access that is superior to either approach used individually.

Acrylic cranioplasty and axial pattern flap following calvarial and cerebral mass excision in a dog.

A 4 kg Chihuahua was presented with seizures and a large mass on his dorsal cranium. The mass had regrown after two previous attempts to remove it. Histological examination had shown the mass to be a multilobular osteochondroma (osteochondrosarcoma). A CT scan revealed destruction of the dorsal cranial bones by the mass and compression of cerebral cortex. A craniotomy was performed to excise the mass and attached skin, leaving a large deficit of calvarial bone and skin. A cranioplasty was performed in situ, using polypropylene mesh and polymethyl methacrylate. A caudal auricular axial pattern flap was placed directly over the cranioplasty to fill the skin defect. This unusual reconstruction resulted in good recovery, function and cosmetic effect, although tumour regrowth was seen within the cerebral cortex.

Temporomandibular ankylosis in the cat: a review of seven cases.

Ankylosis of the temporomandibular joint (TMJ) in the cat is an unusual complication of traumatic lesions involving articular (true ankylosis) or periarticular structures (false ankylosis). Seven cats with true ankylosis of the TMJ (four cases unilateral and three cases bilateral), of which previous trauma had been documented in five cases, were referred to the authors' clinic between September 1991 and October 1996. Radiographic assessment was performed in all cases, using dorsoventral and oblique projections. Five subjects underwent arthroplastic excision of the TMJ and, in the remaining two cases, stretching of the jaws was performed under general anaesthesia. The surgical outcome was satisfactory in all but one case, where partially decreased joint mobility was observed (follow-up time one to five years), but in the two cases where non-surgical treatment was carried out, recurrence of TMJ ankylosis was observed (follow-up time two to five months). In the authors' experience, surgery represents the treatment of choice for TMJ ankylosis in cats. Additional mandibular symphysiotomy can confirm the radiological findings in unilateral cases.

Clinical and histological comparison of tissue damage and healing following incisions with the CO2-laser and stainless steel surgical blade in dogs.

The tissue damage and subsequent healing of skin, linea alba and intestinal wall incisions made with a CO2-laser and a stainless steel surgical blade were evaluated clinically and histologically in dogs (n = 10). The amount of blood lost in each type of skin incision was measured by taking the pre- and postoperative mass of surgical swabs. The tissues were sutured and the skin incisions examined every day. The animals were subsequently euthanased (Day 12) and all incisions examined histologically. A delay in the healing process was observed in the laser incisions of the skin during the first 4 d, but there was no difference in the healing rate of the intestinal wounds or of the linea alba. The blood loss due to the laser incisions was significantly less than that caused by the surgical blade. It was concluded that the CO2-laser can be used with confidence when incising the skin and intestine and that, due to its precision, the surgical blade is by far a more accurate method to incise the linea alba.

[Mandibular and maxillary fractures in dogs and cats]. / Fracturen van de mandibula en maxilla bij hond en kat.

Fractures of the mandible and maxilla are often caused by car accidents or by falling from a height. Frequently the fractures are open, especially when the fracture is located rostrally. During diagnostic work-up, special attention should be given to concomitant injury of the brain, and to cervical and thoracic injuries. The principles of treatment for jaw fractures are identical to those for complicated long bone fractures. Adaptations of techniques are necessary because of the need for undisturbed food intake, the presence of dental elements in the fragments, the poor soft tissue coverage especially in the rostral part of the mandible, and the typical mechanical load of the bones. The dental roots should be avoided when possible. Pharyngostomy prior to fracture treatment allows optimal assessment of the occlusion during surgery. In general, the treatment should permit non-supported food intake by the patient after surgery.

Effect of veterinarian-client-patient interactions on client adherence to dentistry and surgery recommendations in companion-animal practice.

OBJECTIVE: To explore the relationship between veterinarian-client-patient interactions and client adherence to dental and surgery recommendations and to test the a priori hypotheses that appointment-specific client satisfaction and relationship-centered care are positively associated with client adherence. DESIGN: Cross-sectional study. SAMPLE: A subsample of 19 companion-animal veterinarians and 83 clients from a larger observational study consisting of 20 randomly recruited veterinarians and a convenience sample of 350 clients from eastern Ontario. PROCEDURES: Videotaped veterinarian-client-patient interactions containing a dentistry recommendation, surgery recommendation, or both were selected for inclusion from the larger sample of interactions coded with the Roter interaction analysis system. Client adherence was measured by evaluating each patient's medical record approximately 6 months after the videotaped interaction. The clarity of the recommendation, appointment-specific client-satisfaction score, and relationship-centered care score were compared between adhering and nonadhering clients. RESULTS: Among the 83 veterinarian-client-patient interactions, 25 (30%) clients adhered to a dentistry recommendation, surgery recommendation, or both. The odds for adherence were 7 times as great for clients who received a clear recommendation, compared with clients who received an ambiguous recommendation from their veterinarian. Moreover, adhering clients were significantly more satisfied as measured after the interview. Interactions resulting in client adherence also had higher scores for relationship-centered care than did interactions leading to nonadherence. CONCLUSIONS AND CLINICAL RELEVANCE: Veterinarian use of a relationship-centered care approach, characterized as a collaborative partnership between a veterinarian and a client with provision of clear recommendations and effective communication of the rationale for the recommendations, has positive implications for client adherence.