Risk factors for temporary tracheostomy tube placement following surgery to alleviate signs of brachycephalic obstructive airway syndrome in dogs.

OBJECTIVE To identify risk factors for temporary tracheostomy tube placement (TTTP) following surgery for alleviation of signs associated with brachycephalic obstructive airway syndrome (BOAS) in dogs. DESIGN Retrospective case-control study. ANIMALS 122 client-owned dogs with BOAS that underwent surgery to alleviate clinical signs (BOAS surgery). PROCEDURES The medical records database of a veterinary teaching hospital was searched to identify dogs that underwent BOAS surgery from January 2007 through March 2016. Of the 198 dogs identified, 12 required postoperative TTTP (cases); 110 of the remaining 186 dogs were randomly selected as controls. Data regarding signalment and select preoperative, intraoperative, and postoperative variables were extracted from the medical record of each dog. Variables were compared between cases and controls and evaluated for an association with the odds of postoperative TTTP. RESULTS Body condition score, tracheal diameter-to-thoracic inlet ratio, staphylectomy technique, and mortality rate did not differ significantly between cases and controls. The odds of postoperative TTTP increased approximately 30% (OR, 1.3) for each 1-year increase in patient age. Postoperative administration of corticosteroids and presence of pneumonia were also positively associated with the odds of postoperative TTTP. Median duration of hospitalization was significantly longer for cases than controls. CONCLUSIONS AND CLINICAL RELEVANCE Age was positively associated with the odds of TTTP in dogs after BOAS surgery, and TTTP led to prolonged hospitalization. Thus, early identification and intervention may be beneficial for dogs with BOAS. The associations between TTTP and postoperative corticosteroid use or pneumonia were likely not causal, but reflective of patient disease severity.

Pilot study: use of contrast-enhanced ultrasonography in feline renal transplant recipients.

Objectives The study aims were to evaluate the feasibility of contrast-enhanced ultrasonography in feline renal transplant recipients in the post-transplantation period and to report findings in a case with presumptive delayed allograft ischemia. Methods Cats were imaged postoperatively using contrast harmonic ultrasonography after a bolus injection of a microbubble contrast medium. Time/mean pixel intensity curves were generated for cortical and medullary regions of interest in the renal allograft in each cat. Arrival time, time to peak, wash-in slope, wash-out slope, mean transit time and renal blood flow were calculated for each area. Results Within the renal cortices of cats without ureteral obstruction 1 day post-transplantation, arrival time was 2.0-6.3 s, time to peak was 3.6-30.1 s, wash-in rate was 2.45-41.14 mean pixel intensity (MPI)/s, wash-out rate was -2.01 to -0.47 MPI/s and blood flow was 6.1-106.5 MPI/s. Ratio mean transit time was 0.29-1.29. Typical cortical and medullary perfusion patterns were observed in these cats. In one cat with delayed graft ischemia followed by presumptive acute transplant rejection, dynamic and heterogeneous cortical and medullary perfusion was demonstrated. Decreases in cortical blood flow were paralleled by elevated serum creatinine. Conclusions and relevance Contrast-enhanced ultrasonography can be used in feline renal transplant recipients and provides both qualitative and quantitative data regarding renal allograft perfusion.

Evaluation of Gastroesophageal Reflux in Anesthetized Dogs with Brachycephalic Syndrome.

Brachycephalic airway syndrome may predispose to gastroesophageal reflux (GER) because of the high negative intrathoracic pressures required to overcome conformational partial upper airway obstruction. To investigate this, 20 dogs presenting for elective correction of brachycephalic airway syndrome (cases) and 20 non-brachycephalic dogs (controls) undergoing other elective surgeries were prospectively enrolled. Dogs underwent a standardized anesthetic protocol, and esophageal pH was monitored. Signalment, body weight, historical gastrointestinal and respiratory disease, complete blood count, serum biochemical values, radiographic findings, and anesthetic and surgical time were compared between cases and controls, and dogs that did and did not have basic (pH > 7.5), acidic (pH < 4), or any GER. Controls had higher mean esophageal pH (6.3) compared to cases (5.6, P = .019), but there was no difference in % with GER (cases 60%, controls 40%, P = .34). When all dogs were evaluated, dogs with GER had increased creatinine (P = .01), % positive for esophageal fluid on radiographs (P = .05), and body weight (P = .04) compared to those without GER. GER was common in both cases and controls, and cases had lower esophageal pH; however, greater numbers are required to determine if a true difference exists in % GER.

COMPARISON OF TRANSVERSE COMPUTED TOMOGRAPHIC EXCRETORY UROGRAPHY IMAGES AND MAXIMUM INTENSITY PROJECTION IMAGES FOR DIAGNOSING ECTOPIC URETERS IN DOGS.

Computed tomographic maximum intensity projection (MIP) images have been shown to improve reader confidence in their diagnoses and to improve detection of vascular structures and pulmonary nodules. The objectives of this method comparison study were to compare transverse source computed tomographic excretory urography (CTEU) images to two, five, and 10 slab thick MIP images for diagnosing canine ectopic ureters, compare reader confidence, and evaluate interobserver agreement. Two board-certified veterinary radiologists and a board-certified small animal internist blindly reviewed transverse source CTEU and two, five, and 10 slab thick MIP images of 24 dogs enrolled in the study. Inclusion criteria included a diagnostic CTEU and either cystoscopic or surgical confirmation of the presence or absence of ureteral ectopia. Eleven dogs were confirmed to have 17 ectopic ureters at surgery and/or cystoscopically. There was no significant difference in reader diagnoses between viewing methods or between viewing methods and the surgical/cystoscopic findings (P < 0.001). Reader confidence was significantly greater on two (P = 0.0080) and five (P = 0.0009) slab thick MIP images with significant interobserver agreement between readers for all viewing methods (P values ranging between 0.0363 and <0.001). In addition, the diagnostic accuracy of MIP images was similar to or better than transverse source CTEU images, when assessed by a radiologist. The study results suggest that CTEU is a reliable imaging technique for diagnosing canine ectopic ureters among specialists of varied experience. In addition, thin slice reconstructed MIP images improve reader confidence and potentially diagnostic accuracy, and thus their use should be considered, especially in more challenging cases.

BILATERAL HYDRONEPHROSIS IN A SUGAR GLIDER (PETAURUS BREVICEPS).

An adult, intact male sugar glider ( Petaurus breviceps ) presented for acute caudal abdominal swelling. Treatment by the referring veterinarian included aspiration of urine from the swelling. On physical examination, mild depression, pale mucus membranes, and caudal abdominal swelling were noted. Focused ultrasonographic assessment revealed a fluid-filled caudal abdominal structure and subjective bladder wall thickening. The following day, the sugar glider was severely depressed. Hematology results included hypoglycemia, hyperkalemia, hyponatremia, and azotemia. Ultrasonography revealed bilateral hydronephrosis and hydroureter. Despite supportive care, the animal died. Postmortem examination confirmed bilateral ureteral dilation, renal petechial hemorrhage, and dilation of the right renal pelvis. Submucosal edema, hemorrhage, and lymphoplasmacytic infiltration of the urinary bladder, ureters, and renal pelvises were noted. Hyperplasia of the urinary bladder and ureteral epithelium, coupled with inflammation, may have caused functional obstruction leading to bilateral hydronephrosis and hydroureter. This is the first reported case of hydronephrosis in a marsupial.

Effect of sensor location in dogs on performance of an interstitial glucose monitor.

OBJECTIVE To identify variations in glucose values concurrently obtained by use of a continuous glucose monitoring system (CGMS) at the same site, reliability of results for each site, lag time for each site, and influence of site thickness on CGMS accuracy. ANIMALS 8 random-source research dogs. PROCEDURES In experiment 1, 8 CGMS sensors were implanted bilaterally at 1 site (4 sensors/side) in 4 dogs. In experiment 2, 2 CGMS sensors were implanted bilaterally at each of 4 sites (1 sensor/side) in 8 dogs; 4 of those 8 dogs then were subjected to a glycemic clamp technique. The CGMS results were compared among sensors and with criterion-referenced results during periods of euglycemia for all 8 dogs and during hyperglycemia and hypoglycemia for 4 dogs during the glycemic clamp procedure. RESULTS Differences (median, -7 mg/dL; interquartile range [IQR], -18.75 to 3 mg/dL) between CGMS and criterion-referenced glucose concentrations differed significantly among dogs and sites; during euglycemia, they were not different from the expected normal variation between multiple sensors concurrently implanted at the same site. Differences (median, -35 mg/dL; IQR, -74 to -15 mg/dL) between CGMS and criterion-referenced concentrations were greater during changes in glucose concentrations. Thoracic sensors were most accurate but had the shortest mean functional life. CONCLUSIONS AND CLINICAL RELEVANCE Significant differences were detected between CGMS and criterion-referenced glucose concentrations. Overall clinical utility of CGMS was acceptable at all sites, with most of the values from all sensors, sites, and dogs meeting guidelines for point-of-care glucometers.

Elevated synovial fluid concentration of adenosine triphosphate in dogs with osteoarthritis or sodium urate-induced synovitis of the stifle.

Adenosine triphosphate has been shown to stimulate nociceptive nerve terminals in joints. Elevated synovial fluid adenosine triphosphate concentrations as well as a correlation between synovial fluid adenosine triphosphate concentrations and osteoarthritic knee pain has been demonstrated in humans, but not yet in dogs. This study documented elevated synovial fluid adenosine triphosphate concentrations in the stifles of dogs with secondary osteoarthritis and urate-induced synovitis, as compared to normal stifles.

Diagnostic imaging of peripheral vestibular disease in a Chinese goose (Anser cygnoides).

A 20-year-old Chinese goose (Anser cygnoides) presented for severe left-sided head tilt and circling to the left. Peripheral vestibular disease associated with otitis media extending into the left quadrate bone was diagnosed by magnetic resonance imaging and computed tomography. Otoscopy confirmed a ruptured tympanic membrane, and a brainstem auditory evoked response test confirmed loss of hearing in the affected ear. Surgery to remove the caseous material and long-term medical therapy improved the bird's head tilt and quality of life. Otitis, hearing loss, and vestibular disease are rare in birds but can be managed after appropriate investigation. This is the first reported use of multiple advanced diagnostic tests and successful treatment of vestibular disease in a goose.

Diagnosis and treatment of proventricular nematodiasis in an umbrella cockatoo (Cacatua alba).

CASE DESCRIPTION: A 16-year-old female umbrella cockatoo (Cacatua alba) was referred to the University of Georgia College of Veterinary Medicine for evaluation of a 3-year seasonal history of lethargy and weight fluctuation. CLINICAL FINDINGS: Abnormalities detected via clinicopathologic analyses included mild leukocytosis, heterophilia, and lymphopenia consistent with a stress leukogram. Previous fecal examinations failed to diagnose enteric parasite infestation. Results of a fecal flotation test with Sheather sugar solution revealed spirurid eggs (Spiruroidea). Coelomic radiography revealed a widened cardiohepatic waist with increased soft tissue opacity at the level of the hepatic silhouette. The caudal thoracic and abdominal air sacs bilaterally appeared compressed against the coleomic wall. The proventriculus was increased in diameter, with a proventriculus-to-keel ratio of 1.0. Coelomic ultrasonography and positive-contrast upper gastrointestinal radiography revealed severe thickening and irregularity of the proventricular wall. The animal was anesthetized for an endoscopic examination of the upper gastrointestinal tract. Intralesional nematodes were identified on histologic examination of biopsy specimens from the proventriculus. TREATMENT AND OUTCOME: Effective fenbendazole treatment (15 mg/kg [6.8 mg/lb], PO, alternating between 5 days of treatment and 5 days of no treatment, which continued for 4 periods) was confirmed by repeated endoscopy and fecal examinations. The bird remained free of clinical signs 27 months after diagnosis and treatment. CLINICAL RELEVANCE: Antemortem diagnosis of proventricular nematodiasis has not been reported in psittacines. Spirurid nematode eggs are shed intermittently, which may lead to false-negative results on a single routine fecal examination. In this patient, radiography, endoscopy, and histologic evaluation facilitated antemortem diagnosis. This is the first report of successful treatment of this condition in psittacines.

Intraoperative contrast-enhanced ultrasonography of normal canine jejunum.

Nine normal juvenile dogs were evaluated with direct jejunal contrast-enhanced ultrasonography via midline celiotomy. Three different doses of ultrasound contrast medium (Definity®) were injected through a peripheral venous catheter. Time-intensity curves were used to calculate baseline, time to initial rise, inflow slope, time-to-peak, peak intensity (PI), and outflow slope for each administered dose. PI was directly proportional to dose. Outflow slope was similar for all patients, independent of dose. The most favorable images were acquired with a dose of 0.030 ml/kg given as a rapid intravenous manual bolus. The technique and normal jejunal perfusion pattern described herein may provide useful data for evaluation of intestinal vascular, inflammatory, and neoplastic disease in the dog.

Ultrasonographic and magnetic resonance imaging diagnosis of an oropharyngeal wood penetrating injury in a dog.

A 5 yr old female intact English setter with a 17 day history of a penetrating oropharyngeal wound was referred for cervical swelling and pain. Physical examination revealed swelling at the left lateral aspect of the cranial cervical region. Pain was elicited upon flexion, extension, and leftward movement of the neck. Neurologic deficits were not identified. Cervical ultrasonography showed a 0.4 cm × 2.3 cm linear, hyperechoic structure in the soft tissues ventrolateral to the first (C1) and second (C2) cervical vertebrae. MRI demonstrated a linear structure 2 cm in length adjacent to the cranial aspect of C2. The foreign material was isointense to hyperintense on precontrast T1-weighted images, isointense on postcontrast T1-weighted images, and hypointense on T2-weighted images relative to adjacent muscle. Abnormalities within the spinal canal were not identified. Upon surgical exploration, a reed foreign body was identified deep to the serratus ventralis muscle. The patient was normal on follow-up evaluations 4 wk postsurgically.

Digital radiographic artifacts.

Artifacts in radiography can be detrimental to interpretation by decreasing visualization or altering the appearance of an area of interest. Digital radiographs (DRs) have their own unique artifacts, and recognition of these artifacts is important to prevent misinterpretation and help identify the cause. A DR artifact can be categorized according to the step during which it was created. The major categories are preexposure, exposure, postexposure, reading, and workstation artifacts. Understanding the cause of artifacts and method of resolution is paramount in acquiring high-quality digital images.

Artifacts in digital radiography.

Digital radiography is becoming more prevalent in veterinary medicine, and with its increased use has come the recognition of a number of artifacts. Artifacts in digital radiography can decrease image quality and mask or mimic pathologic changes. They can be categorized according to the step during which they are created and include preexposure, exposure, postexposure, reading, and workstation artifacts. The recognition and understanding of artifacts in digital radiography facilitates their reduction and decreases misinterpretation. The purpose of this review is to name, describe the appearance, identify the cause, and provide methods of resolution of artifacts in digital radiography.