Acquired dysfunction of CFTR underlies cystic fibrosis-like disease of the canine gallbladder.

Mucocele formation in dogs is a unique and enigmatic muco-obstructive disease of the gallbladder caused by the amassment of abnormal mucus that bears striking pathological similarity to cystic fibrosis. We investigated the role of cystic fibrosis transmembrane conductance regulatory protein (CFTR) in the pathogenesis of this disease. The location and frequency of disease-associated variants in the coding region of CFTR were compared using whole genome sequence data from 2,642 dogs representing breeds at low-risk, high-risk, or with confirmed disease. Expression, localization, and ion transport activity of CFTR were quantified in control and mucocele gallbladders by NanoString, Western blotting, immunofluorescence imaging, and studies in Ussing chambers. Our results establish a significant loss of CFTR-dependent anion secretion by mucocele gallbladder mucosa. A significantly lower quantity of CFTR protein was demonstrated relative to E-cadherin in mucocele compared with control gallbladder mucosa. Immunofluorescence identified CFTR along the apical membrane of epithelial cells in control gallbladders but not in mucocele gallbladder epithelium. Decreases in mRNA copy number for CFTR were accompanied by decreases in mRNA for the Cl-/[Formula: see text] exchanger SLC26A3, K+ channels (KCNQ1, KCNN4), and vasoactive intestinal polypeptide receptor (VIPR1), which suggest a driving force for change in secretory function of gallbladder epithelial cells in the pathogenesis of mucocele formation. There were no significant differences in CFTR gene variant frequency, type, or predicted impact comparing low-risk, high-risk, and definitively diagnosed groups of dogs. This study describes a unique, naturally occurring muco-obstructive disease of the canine gallbladder, with uncanny similarity to cystic fibrosis, and driven by the underlying failure of CFTR function.NEW & NOTEWORTHY Cystic fibrosis transmembrane conductance regulatory protein (CFTR) genomic variants and expression of mRNA, protein, and electrogenic anion secretory activity of CFTR were characterized in dog gallbladder. Acquired inhibition of CFTR expression by gallbladder epithelium was identified as underpinning a naturally occurring muco-obstructive disease of the dog gallbladder that bears striking pathological similarity to animal models of cystic fibrosis.

Evaluation of thoracic duct ligation and unilateral subphrenic pericardiectomy via a left fourth intercostal approach in normal canine cadavers.

OBJECTIVE: To investigate a left-sided fourth intercostal approach to thoracic duct (TD) ligation and unilateral subphrenic pericardiectomy in dogs. STUDY DESIGN: Retrospective computed tomography (CT) review and cadaveric study. ANIMALS: Thirteen dogs with idiopathic chylothorax and 10 canine cadavers. METHODS: A retrospective study of CT lymphangiograms in client-owned dogs with idiopathic chylothorax evaluated location and branching of the TD at the left fourth intercostal space. A cadaveric study evaluated the efficacy of TD ligation at this site. Following methylene blue mesenteric lymph node injection, TDs were identified through a left fourth intercostal thoracotomy, ligated, and sealed. Unilateral subphrenic pericardiectomy was performed through the same incision. Computed tomography scans were performed to determine the success of TD ligation. RESULTS: A review of lymphangiograms revealed a single TD in 10/13 clinical cases at the fourth intercostal space. Three cases had additional branches. Thoracic duct ligation via a left fourth intercostal thoracotomy was successful in nine out of 10 cadavers. A single branch was noted intraoperatively in six out of 10, and two branches were noted in four out of 10 cadavers. All branches were observed on the left side of the esophagus. CONCLUSION: TD ligation at the left fourth intercostal space was successfully performed in 9/10 canine cadavers and appeared feasible in a retrospective review of 10/13 clinical cases. Unilateral subphrenic pericardiectomy can also be performed via this approach. CLINICAL SIGNIFICANCE: Fewer thoracic duct branches at this location in comparison with the standard caudal location may simplify TD ligation. If elected, unilateral subphrenic pericardiectomy can be performed through the same incision. Further investigation in clinical patients is warranted.

Development of an ultrasound-guided transgluteal injection of the pudendal nerve in cats: a cadaveric study.

OBJECTIVE: To develop an ultrasound-guided interfascial plane technique for injection of the pudendal nerve near its sacral origin in cats. STUDY DESIGN: Prospective, randomized, anatomical study. ANIMALS: A group of 12 feline cadavers. METHODS: Gross and ultrasound anatomy of the ischiorectal fossa, the pudendal nerve relationship with parasacral structures, and the interfascial plane were described. Computed tomography was employed to describe a cranial transgluteal approach to the pudendal nerve. Bilateral ultrasound-guided injections were performed in eight cadavers using low [(LV) 0.1 mL kg-1] or high volume [(HV) 0.2 mL kg-1] of ropivacaine-dye solution. Dissections were performed to determine successful staining of the pudendal nerve (>1 cm) and inadvertent staining of the sciatic nerve, and any rectal, urethral, or intravascular puncture. Pudendal nerve staining in groups LV and HV were compared using Fisher's exact and Wilcoxon rank-sum test as appropriate (p = 0.05). RESULTS: The pudendal nerve and its rectal perineal and sensory branches coursed through the ischiorectal fossa, dorsomedial to the ischiatic spine. The pudendal nerve was not identified ultrasonographically, but the target plane was identified between the sacral transverse process, the ischiatic spine, the pelvic fascia and the rectum, and it was filled with dye solution. Both branches of the pudendal nerve were completely stained 75% and 87.5% in groups LV and HV, respectively (p = 1.00). The dorsal aspect of the sciatic nerve was partially stained in 37% of injections in group HV. Rectal or urethral puncture and intravascular injection were not observed. CONCLUSIONS AND CLINICAL RELEVANCE: In cats, ultrasound-guided cranial transgluteal injection successfully stained the pudendal nerve in at least 75% of attempts, regardless of injectate volume. Group HV had a greater probability of sciatic nerve staining.

A randomized, prospective, comparative trial of a variable-angle versus fixed-angle endoscope for exploratory thoracoscopy in canine cadavers.

OBJECTIVE: To compare the efficacy of a variable-angle endoscope (VAE) for canine thoracoscopic exploration to a traditional fixed-angle endoscope (FAE). STUDY DESIGN: Randomized, prospective, comparative study. SAMPLE POPULATION: Five fresh canine cadavers. METHODS: Twelve predetermined anatomical locations were labeled after median sternotomy in each cadaveric thorax. Two board-certified veterinary surgeons performed thoracoscopic evaluation of each thorax using a fixed-angle (30°) and a variable-angle (0°-120°) endoscope with and without lungs mechanically ventilated. The order of surgeon, lung ventilation, and endoscope were determined using a randomized block design. Time to visualize each anatomical location was compared for surgeon, endoscope, and lung ventilation status. Primary outcome measures were time to individual anatomical location, total simulated thoracoscopic exploration time, and ability to identify anatomical location within the designated time period. RESULTS: Lung ventilation (difference = 184 seconds, P = .015, 95% CI = 45-342 seconds) and endoscope type (difference = 112 seconds, P = .029; 95% CI = 10-213 seconds) had an effect on the cumulative time for complete thoracoscopic exploration. The VAE shortened the time to identify three of the 12 anatomical locations when controlling for the effects of lung ventilation. Use of the VAE did not improve time to identification for any locations compared to the FAE when lungs were not ventilated. The VAE facilitated significantly shorter cumulative thoracoscopic exploration time compared with the FAE. Failure to identify predetermined locations was more common with the FAE than with the VAE. CONCLUSION: Use of a rigid VAE decreased cumulative thoracoscopic exploration time and provided an alternative to one-lung ventilation for circumventing the visual impediments of lung ventilation. CLINICAL SIGNIFICANCE: This cadaveric study provides evidence that one-lung ventilation and use of a VAE may improve surgeon efficiency during exploratory thoracoscopy.

Computed tomography in two recumbencies aides in the identification of pulmonary bullae in dogs with spontaneous pneumothorax.

Spontaneous pneumothorax presents a unique diagnostic and therapeutic challenge in veterinary medicine, specifically with regard to accurate identification of bullous lesions. Positioning of dogs with spontaneous pneumothorax during CT has not previously been evaluated. This retrospective, diagnostic accuracy study was performed to evaluate the sensitivity, positive predictive value (PPV), and interobserver variability for detection of pulmonary bullae with dogs positioned in multiple recumbencies. Dogs underwent CT in sternal and dorsal recumbency followed by thoracic exploration via median sternotomy. Three American College of Veterinary Radiology-certified veterinary radiologists blinded to surgical findings reviewed dorsal and sternal images simultaneously. Severity of pneumothorax, degree of atelectasis, lesion location and size, and view in which lesions were most confidently identified were compared to surgical and histologic findings. Sensitivities and PPVs for bulla detection ranged from 57.7% to 69.2% and 62.1% to 78.9%, respectively. For two of the 3 radiologists, the location of bullae in the thorax was significantly associated with the recumbency in which the lesion was best identified. Degree of atelectasis was found to be associated with the ability to identify lesions (P ≤ .02). The interobserver variability for identification was good (κ = 0.670). The sensitivity of CT when performed in both sternal and dorsal recumbency is similar to that previously reported. Because the distribution of bullae is unknown prior to advanced imaging and bulla location affects which recumbency is most useful for identification, acquisition of CT images in both sternal and dorsal recumbency may improve detection of bullous lesions and aid surgical planning.

Successful vascularized jejunal patch graft to treat severe orad duodenal injury secondary to foreign body obstruction in a dog.

OBJECTIVE: To report the surgical treatment and outcome of an adult dog with a duodenal perforation treated with a vascularized jejunal patch graft. STUDY DESIGN: Case report. ANIMAL: A 1-year-old castrated male boxer dog. METHODS: Damage to a duodenal segment containing the major and minor papillae was repaired with a vascularized jejunal graft. A segment of healthy jejunum was mobilized maintaining the jejunal vessels, and a donor site anastomosis was performed. The vascularized jejunal graft was incised on the antimesenteric border creating a rectangular segment, which was trimmed and sutured to the duodenal recipient site as a patch graft to repair the defect. RESULTS: The dog recovered well without major complications. Within 2 weeks, appetite and bowel movements were normal, with no episodes of vomiting. Infrequent regurgitation resolved without medical therapy. CONCLUSION: A vascularized jejunal patch graft is a feasible option for successful surgical repair of duodenal injury in the dog. CLINICAL SIGNIFICANCE: This report describes a novel surgical repair technique for treatment of gastrointestinal injuries.

Ability of positive and negative contrast computed tomographic peritoneography to delineate canine liver lobe fissures.

OBJECTIVE: To determine the efficacy of contrast peritoneography in delineating liver lobe fissures by using computed tomography (CT). STUDY DESIGN: Prospective cross-sectional study. ANIMALS: Canine cadavers (n = 10). METHODS: An abdominal CT image of each cadaver was obtained under three conditions: without peritoneal contrast (precontrast), after insufflation of the peritoneal cavity with CO2 (negative contrast), and after intraperitoneal administration of iohexol (positive contrast). Images were reconstructed in three planes. Three reviewers independently scored each plane/contrast combination. Observers measured the length of each fissure in each plane. The measurable length of fissures was compared between techniques but was not compared with the actual length on cadavers. RESULTS: When assessment of all fissures was combined, measurements were obtained in 96 to 108 of 120 (80%-90%) positive contrast studies, 56 to 96 of 120 (47%-80%) negative contrast studies, and 12 to 32 of 120 (10%-27%) precontrast CT images. All observers measured fissures in all planes that were approximately two times longer on positive compared with negative contrast studies and two times longer on negative contrast studies compared with CT images without contrast. Measurable fissure lengths were greater on positive contrast CT images (P < .0001) than on other CT images. CONCLUSION: Positive contrast CT peritoneography improved the delineation of hepatic interlobar fissures in normal canine cadavers. CLINICAL SIGNIFICANCE: These results justify further studies to determine the ability to locate large hepatic masses in dogs with positive CT. Positive contrast CT peritoneography may assist treatment planning in dogs with large hepatic tumors.

Validation of a model of feline ureteral obstruction as a tool for teaching microsurgery to veterinary surgeons.

OBJECTIVE: To assess the content and face validity of a model of an obstructed feline ureter as a tool for teaching ureteral microsurgery. STUDY DESIGN: Prospective, experimental study. SAMPLE POPULATION: Seven expert and 11 novice microsurgeons. METHODS: The model was created from latex rubber with an inner diameter of 0.8 mm and an outer diameter of 5 mm. The "ureter" was created with an inner compartment, a thin wall, and a soft, outer layer mimicking periureteral fat. A "ureterolith" 0.8-1.2 mm in diameter was placed inside the inner compartment by using a blunt-tipped cannula. A standardized "ureterotomy" was performed by 7 expert and 11 novice microsurgeons. Both groups completed questionnaires evaluating the content and face validity of the model using subjective measures and a 5-point Likert scale. Reliability was analysed by calculation of Cronbach's α for all questions to ensure α ≥ .7. The median responses to each question were compared between groups with a nonparametric independent samples median test. P < .05 was considered significant. RESULTS: The Cronbach's α for the experts and the novices for content validity questions was .7 and .9, respectively, and for the face validity questions it was .7 and .8, respectively. The model was rated to have excellent content validity and very good face validity. CONCLUSION AND IMPACT: The model elicited positive responses from expert and novice microsurgeons and can be recommended as a tool for teaching ureteral microsurgery. A model validated by face and content measures should next be scrutinized by determination of construct, concurrent, and predictive validity by using objective measures.

Lung lobe torsion in dogs: 52 cases (2005-2017).

OBJECTIVE: To report outcomes and risk factors for mortality in dogs that underwent surgical management of lung lobe torsion. STUDY DESIGN: Retrospective case series from 5 veterinary teaching hospitals (2005-2017). ANIMALS: Fifty dogs with 52 instances of lung lobe torsion. METHODS: Data collected from medical records included signalment, clinical findings, results of clinicopathologic testing and diagnostic imaging, surgical treatment, lung lobe affected, intraoperative and postoperative complications, histopathologic and microbiologic findings, and outcome. Follow-up was obtained from medical records and telephone contact with primary care veterinarians. RESULTS: Fifty-two instances of lung lobe torsion were identified in 50 dogs, with a median follow-up of 453 days (range, 0-3075). Forty-six (92%) dogs survived to discharge. Dogs with concurrent torsion of the right cranial and middle lung lobes were less likely to survive (2/4) than those with torsion of the left cranial lung lobe (22/22). No other risk factors for mortality prior to hospital discharge were identified. Overall median survival time after hospital discharge was 1369 days. Four dogs had >1 episode of lung lobe torsion. CONCLUSION: The percentage of dogs surviving to discharge after surgical treatment of lung lobe torsion was higher than previously reported. The short- and long-term prognosis was excellent with surgical treatment of lung lobe torsion. CLINICAL SIGNIFICANCE: Surgery should be recommended when lung lobe torsion is suspected because of the high survival to discharge rate and excellent long-term prognosis.

Carotid artery bursting pressure and seal time after multiple uses of a vessel sealing device.

OBJECTIVE: To determine any loss of function of a single-use bipolar vessel sealing device after repeated sterilization and use on canine carotid arteries. STUDY DESIGN: Ex vivo; randomized block design (dog). SAMPLE POPULATION: Carotid artery segments (n = 90) from 15 canine cadavers. METHODS: Six 10-mm LigaSure Atlas 20 cm devices (Covidien Inc, Minneapolis, Minnesota) were used to seal canine carotid artery segments in one cadaver, then resterilized using ethylene oxide and reused in a second cadaver, and so on, for a total of 15 uses/15 cadavers per LigaSure. Sealing times and bursting pressures of each carotid artery segment after each use were recorded. Charring and sticking at each seal location was qualitatively assessed. RESULTS: Mean (SD) sealing time for all segments was 5.3 (1.4) seconds, ranging from 2.7 to 9.5 seconds. There was no significant change in sealing time for successive uses (P = .117). The mean (SD) bursting pressure for all segments was 1041.3 (316.7) mm Hg, ranging from 355 to 1555 mm Hg. There was no change in bursting pressure across uses (P = .57). Moderate sticking and charring occurred at each time point but was not subjectively different throughout the study. CONCLUSION: The LigaSure Atlas vessel sealing device can be used and resterilized with ethylene oxide up to 15 times with no change in sealing time or bursting pressure of the seal.

IMAGING DIAGNOSIS-USE OF RADIOGRAPHY, COMPUTED TOMOGRAPHY, AND ENDOSCOPY IN THE DIAGNOSIS OF ESOPHAGEAL PERFORATION BY AN EXTRA-LUMINAL TRACHEAL RING PROSTHESIS IN A GOLDEN RETRIEVER.

A 6-year-old neutered male, Golden retriever presented with regurgitation and excitement-induced coughing. Two years prior, extra-thoracic tracheal collapse was diagnosed and extra-luminal tracheal ring prostheses were placed. Radiographs at presentation showed mineralized and undulant cervical tracheal cartilages. A dorsally broad-based soft tissue opacity bulged into the caudal cervical tracheal lumen. Esophageal dysmotility and barium accumulation were identified at this level on contrast esophography. Computed tomography showed migration of a prosthetic tracheal ring, resulting in perforation of the esophagus. Hair, foreign material, and dynamic tracheal narrowing were identified on esophagoscopy and tracheoscopy, respectively. Esophagostomy and foreign body removal were performed.

The Effect of Specimen Preparation on Post-Excision and Post-Fixation Dimensions, Translation, and Distortion of Canine Cadaver Skin-Muscle-Fascia Specimens.

OBJECTIVE: To assess the effect of various tissue apposition techniques on specimens after formalin fixation, and to assess canine cadaveric composite skin-muscle-fascia specimen changes after excision without and with addition of a tumor model. STUDY DESIGN: Canine cadaveric study; unbalanced paired design. ANIMALS: Fresh canine cadavers (n = 30) METHODS: Experiment 1: Paired 7 cm diameter, circular skin-muscle-fascia specimens were harvested bilaterally from three sites (thorax, abdomen, and thigh) on 10 cadavers. For each pair, the skin-to-fascia was sutured with a circumferential continuous pattern in one specimen and left unsutured in the other during excision. Specimen length and width were measured post-excision and post-fixation. Specimen rotation, translation, and distortion was measured post-fixation. Experiment 2: A subcutaneous tumor model was implanted at 2 sites (neck, thorax) on 20 cadavers and specimens were then excised with 2 cm lateral margins and a deep fascial plane. Three suturing techniques of the skin-to-fascia at both sites were performed during excision: unsutured versus circumferential continuous suture (10 pairs) or circumferential versus 4 interrupted quadrant sutures (10 pairs). Lateral margins were compared post-excision and post-fixation. RESULTS: Experiment 1: There was significant reduction in the length and width of the fascia and skin post-excision, but no further reduction after fixation. The circumferential suture decreased rotation and translation of the tissue layers but did not significantly affect specimen shrinkage or distortion compared with the unsutured specimen. Experiment 2: All 4 lateral margins decreased significantly post-excision and post-fixation compared with the planned pre-excision margins. No difference was found between any of the 4 lateral margins for any skin-to-fascia suture technique. CONCLUSION: Canine skin-muscle-fascia specimens significantly decrease in size from gross pre-excision dimensions after removal. Suturing the specimen during surgery before excision will significantly improve alignment of tissue planes without creating distortion of the sample, but may alter the length, width, and lateral margins of the specimen.

Comparison of radiography and computed tomography for determining tracheal diameter and length in dogs.

OBJECTIVE: To compare radiographic and computed tomography (CT) measurements of tracheal size as would be made for the purpose of tracheal stent size selection. STUDY DESIGN: Cross-over. ANIMALS: Dogs (n = 15). METHODS: Canine cadavers without evidence of tracheal or respiratory disease were used for CT and digital radiography of the neck and thorax. Three observers each made 3 independent measurements at each of 5 tracheal locations, and also measured tracheal length, on each radiograph and for each CT scan on each cadaver. RESULTS: CT tracheal measurements were on average 1.03 mm larger (P < .01) compared with radiographic measurements for all 3 observers. CONCLUSIONS: Radiographic measurements of the canine trachea consistently underestimate tracheal size, and CT measurements are preferable for selecting tracheal stent size.

The effect of photodynamic therapy on cisterna chyli patency in rats.

OBJECTIVE: To radiographically and histologically evaluate the effects of photodynamic therapy on the cisterna chyli in rats. STUDY DESIGN: Experimental study. ANIMALS: Adult male Sprague-Dawley rats (n = 60). METHODS: Cecal lymph nodes were injected with the photodynamic compound verteporfin. A 690 nm, 500 mW diode laser was then directed at the area of the cisterna chyli for either 0, 1.5, or 3 minutes. Cisterna chyli patency was evaluated using lymphography, and histologic changes were evaluated on postoperative Days 1, 3, 5, 7, and 14. RESULTS: Histologically, minimal to marked injury to the cisternal and/or pericisternal tissues was present in all treated rats at all time periods. Radiographically, 8/20 cisternae were occluded in the 1.5-minute treatment group (including 1/4 on Day 1, 2/4 on Day 3, 3/4 on Day 5, 0/4 on Day 7, and 2/4 on Day 14), and 9/20 cisternae were occluded in the 3-minute treatment group (including 0/4 on Day 1, 1/4 on Day 3, 3/4 on Day 5, 3/4 on Day 7, and 2/4 on Day 14). There was minimal to no histologic evidence of tissue injury in control rats. All control cisternae were radiographically open. CONCLUSIONS: Further investigations into the timing of laser application and light dose, or alternative photodynamic agents are required to limit injury to adjacent tissues and to improve the effectiveness of cisternal photoablation.

Hemipelvectomy: outcome in 84 dogs and 16 cats. A veterinary society of surgical oncology retrospective study.

OBJECTIVE: To report clinical findings, perioperative complications and long-term outcome in dogs and cats that had hemipelvectomy surgery for treatment of neoplasia. STUDY DESIGN: Multi-institutional retrospective case series. ANIMALS: Dogs (n = 84) and cats (16). METHODS: Medical records (January 2000 to December 2009) of dogs and cats that had hemipelvectomy at participating institutions were reviewed. Postoperative progress and current status of the patient at the time of the study was determined by either medical record review, or via telephone contact with the referring veterinarian or owner. RESULTS: Complications were infrequent and usually minor. Hemorrhage was the main intraoperative complication; 2 dogs required blood transfusion. One dog developed an incisional hernia. In dogs, hemangiosarcoma had the worst prognosis with a median survival time (MST) of 179 days. MST for chondrosarcoma (1232 days), osteosarcoma (533 days), and soft tissue sarcoma (373 days) were not statistically different. Median disease-free interval (DFI) for local recurrence of all tumor types was 257 days. Cats had 75% survival at 1 year, which was significantly longer than dogs. CONCLUSIONS: Survival times for most tumor types can be good, but surgical margins should be carefully evaluated to ensure complete tumor removal. Adjuvant therapies may be advisable particularly for dogs to reduce rates of local recurrence or distant metastasis.

Increased lipogenesis and lipidosis of gallbladder epithelium in dogs with gallbladder mucocele formation.

BACKGROUND: Gallbladder disease in people is frequently associated with disorders of lipid metabolism and metabolic syndrome. A recently emergent gallbladder disease of dogs, referred to as mucocele formation, is characterized by secretion of abnormal mucus by the gallbladder epithelium and is similarly associated with hyperlipidemia, endocrinopathy, and metabolic dysfunction. The cause of gallbladder mucocele formation in dogs is unknown. METHODS: A prospective case-controlled study was conducted to gain insight into disease pathogenesis by characterization of plasma lipid abnormalities in 18 dogs with gallbladder mucocele formation and 18 age and breed matched control dogs using direct infusion mass spectrometry for complex plasma lipid analysis. This analysis was complemented by histochemical and ultrastructural examination of gallbladder mucosa from dogs with gallbladder mucocele formation and control dogs for evidence of altered lipid homeostasis of the gallbladder epithelium. RESULTS: Gallbladder mucocele formation in dogs carried a unique lipidomic signature of increased lipogenesis impacting 50% of lipid classes, 36% of esterified fatty acid species, and 11% of complex lipid species. Broad enrichment of complex lipids with palmitoleic acid (16:1) and decreased abundance within complex lipids of presumptive omega-3 fatty acids eicosapentaenoic (20:5) and docosahexaenoic (22:6) was significant. Severe lipidosis of gallbladder epithelium pinpoints the gallbladder as involved causally or consequently in abnormal lipid metabolism. CONCLUSION: Our study supports a primary increase in lipogenesis in dogs with mucocele formation and abnormal gallbladder lipid metabolism in disease pathogenesis.

Outcomes and complications associated with epicardial pacemakers in 28 dogs and 5 cats.

OBJECTIVE: To report signalment, history, indications, complications and outcome for 28 dogs and 5 cats in which 34 permanent epicardial pacing leads were surgically placed by transdiaphragmatic approach (32) or intercostal thoracotomy (2). METHODS: Medical records (2005-2010) were reviewed. Signalment, age, species, gender, clinical signs, presence of structural heart disease and/or congestive heart failure, ECG diagnosis, body weight (<10 or >10 kg), and overall survival rate were recorded. Statistical correlations were made between these variables and major and minor complications rates. RESULTS: Except for body weight, no statistical differences were identified in prevalence of major (life threatening or requiring replacement of the pacemaker system) or minor (self-limiting) complications; dogs weighing >10 kg had significantly more major complications (P = .03). There was a trend (P = .051) for lower survival in animals that had major complications. CONCLUSIONS: Larger dogs (>10 kg) may be predisposed to more major complications with epicardial pacemaker (EP) implantation. Major complication rate and survival time are similar to those reported for transvenous pacing and therefore implantation of EPs remains a suitable alternative.

Gallbladder microbiota in healthy dogs and dogs with mucocele formation.

To date studies have not investigated the culture-independent microbiome of bile from dogs, a species where aseptic collection of bile under ultrasound guidance is somewhat routine. Despite frequent collection of bile for culture-based diagnosis of bacterial cholecystitis, it is unknown whether bile from healthy dogs harbors uncultivable bacteria or a core microbiota. The answer to this question is critical to understanding the pathogenesis of biliary infection and as a baseline to exploration of other biliary diseases in dogs where uncultivable bacteria could play a pathogenic role. A pressing example of such a disease would be gallbladder mucocele formation in dogs. This prevalent and deadly condition is characterized by excessive secretion of abnormal mucus by the gallbladder epithelium that can eventually lead to rupture of the gallbladder or obstruction of bile flow. The cause of mucocele formation is unknown as is whether uncultivable, and therefore unrecognized, bacteria play any systematic role in pathogenesis. In this study we applied next-generation 16S rRNA gene sequencing to identify the culture-negative bacterial community of gallbladder bile from healthy dogs and gallbladder mucus from dogs with mucocele formation. Integral to our study was the use of 2 separate DNA isolations on each sample using different extraction methods and sequencing of negative control samples enabling recognition and curation of contaminating sequences. Microbiota findings were validated by simultaneous culture-based identification, cytological examination of bile, and fluorescence in-situ hybridization (FISH) performed on gallbladder mucosa. Using culture-dependent, cytological, FISH, and 16S rRNA sequencing approaches, results of our study do not support existence of a core microbiome in the bile of healthy dogs or gallbladder mucus from dogs with mucocele formation. Our findings further document how contaminating sequences can significantly contribute to the results of sequencing analysis when performed on samples with low bacterial biomass.

Cranial internal hemipelvectomy (iliectomy) with limb sparing for a dog with ilial chondrosarcoma: A case report.

Cranial internal hemipelvectomy can be successful for excision of ilial CSA with minimal complications. Iliectomy with adjuvant radiation therapy was well tolerated in a dog with grade II ilial CSA. The dog survived 1,271 days postoperatively and supposedly succumbed to a disease process unrelated to the CSA.

Creation of a Continent Urinary Bladder Reservoir Vascularized by Omentum as a Possible Surgical Option for Canine Trigonal/Urethral Urothelial Carcinoma.

Surgical procedures that maintain continence with minimal complication following resection of trigono-urethral urothelial carcinoma (UC) are limited in canines; therefore, palliative options are often pursued. A feasible tumor resection option may improve disease control and survival. The study's objective was to evaluate a continent urine reservoir created from the urinary bladder body and vascularized solely by omentum. We hypothesized that a viable urine reservoir could be created, and staged omentalization would provide improved vascularity. Nine normal female Beagles were randomized to one of three groups. Group A urinary bladders were transected cranial to the ureteral papillae to create a closed bladder vesicle which was concomitantly omentalized. Group B underwent omentalization two weeks prior to vesicle creation. Based on Group A and B results, Group C underwent neoureterocystostomy and omentalization followed by neoreservoir formation and tube cystostomy 2 weeks later. Serial ultrasounds and histopathology confirmed adequate omental neovascularization in Groups B and C with continent Group C neoreservoirs maintained for 2 months. Some pylectasia and ureteral dilation was documented in all Group C dogs at variable timepoints. Progressive hydroureteronephrosis developed in 2/6 kidneys. Transient azotemia was noted in only 1 Group C dog, although all developed treatable urinary tract infections. The sample size is limited, and the efficacy of this technique in providing disease control for UC is unknown. However, this novel option could allow for primary UC resection while providing continence and limiting complications. Postoperative local or systemic adjuvant therapy, ultrasonographic neoreservoir monitoring, and BRAF analysis would be indicated.