FATAL VENOUS AIR EMBOLISM IN A CAT WITH A RETROPHARYNGEAL DIVERTICULUM

A cat with a 1-year history of oropharyngeal foreign bodies was diagnosed with a pharyngeal diverticulum. The cat experienced fatal cardiac arrest during endoscopy, and postmortem radiographs and ultrasound revealed venous air embolism. Venous air embolism is uncommonly reported in veterinary medicine, but is a risk during any procedure that introduces air into a body cavity. Precautions should be taken during these procedures to help minimize the risk of adverse events.     

CARDIOVASCULAR AND GASTROINTESTINAL RADIOGRAPHIC CONTRAST STUDIES IN THE HORSESHOE CRAB (LIMULUS POLYPHEMUS)

Survey and contrast radiographic studies of the cardiovascular and gastrointestinal systems of the American horseshoe crab (Limulus polyphemus) were undertaken using conventional and flouroscopic techniques. Normal gastrointestinal and cardiovascular structures were difficult to resolve on survey radiographs, but were well visualized with gastrointestinal follow through studies and angiography, respectively. All three contrast agents (iohexol, Gastrografin, and barium sulfate) used for the gastrointestinal studies varied minimally in their radiographic quality and transit times, and all appeared to be safe for use in the horseshoe crab.     

MAGNETIC RESONANCE IMAGING FINDINGS OF EQUINE SOLAR PENETRATION WOUNDS

The magnetic resonance (MR) imaging features, signalment, clinical history and outcome of 55 horses with a penetrating sole injury were evaluated. Our aim was to describe MR imaging findings within the hoof capsule, assess the utility of the technique and give recommendations for the optimal MR imaging protocol to evaluate such injuries. Data from five equine hospitals were analyzed retrospectively. The tract was more likely to be visualized in animals scanned within the first week postinjury. There was no significant predisposition based on breed, age, or gender. T2*W transverse sequences were the most useful for assessment of solar penetrations due to their orientation perpendicular to the deep digital flexor tendon, the reduced scanning time, and the T2* capability of enhancing magnetic susceptibility caused by hemorrhage.     

Biomechanical Comparison of Four Soft Tissue Replacement Materials: An In Vitro Evaluation of Single and Multilaminate Porcine Small Intestinal Submucosa, Canine Fascia Lata, and Polypropylene Mesh

Objective— To compare mechanical performance of 4 soft tissue replacement materials.
Study Design— Experimental.
Sample Population— Polypropylene mesh (PM), single-layer porcine small intestinal submucosa (SIS), multilaminate (4-layer) porcine small intestinal submucosa (MLSIS), and canine fascia lata (FL).
Methods— The mechanical properties of each material were determined by testing to failure on a materials testing machine. Samples of each material (n=10) were tested in 3 different modes: resistance to suture pullout, tensile testing, and push-through testing. PM was tested both parallel (PMa) to and perpendicular (PMb) to its longitudinal cord orientation. SIS and FL were similarly tested in 2 orthogonal directions.
Results— With some exceptions, the following generalizations can be made regarding the mechanical performance of the materials tested:
Suture pullout— FL>PMa=PMb>MLSIS>SIS ( P ≤.04).
Tensile testing —FL>PMa>PMb>MLSIS>SIS ( P ≤.02).
Push-through testing— FL>PM>MLSIS>SIS ( P ≤.003).
Conclusions— PM accommodated a significantly higher load and energy to yield when its longitudinal cords were oriented parallel with the tension axis (PMa). FL performed similarly to the PM, with the exception of limited elongation in tension. MLSIS had biomechanical characteristics that were inferior to FL and PM but superior to SIS.
Clinical Relevance— PM's orientation may need to be considered when used clinically. FL is a biomechanically suitable soft tissue replacement material but its use may be limited by currently available sizes. SIS cannot be recommended in high-strain environments.     

INTEROBSERVER AGREEMENT ON THE ASSESSABILITY OF STANDARD VENTRODORSAL HIP-EXTENDED RADIOGRAPHS AND ITS EFFECT ON AGREEMENT IN THE DIAGNOSIS OF CANINE HIP DYSPLASIA AND ON ROUTINE FCI SCORING

Insufficient agreement on scoring hip quality might be caused by differences in the assessability of a radiograph (exposure, contrast, positioning, and diagnostic quality). We studied the agreement in assessability of standard ventrodorsal hip-extended radiographs by experienced (nine) and inexperienced (21) observers, using the standard subjective method of quality control, currently applied in screening programs. The effect of assessability on the agreement of scoring hip quality [dysplastic vs. nondysplastic and the final Federation Cinologique International (FCI) score] was also investigated. There was a significant difference ( P <0.0001) in agreement on assessability between the experienced and inexperienced observers. In 68% of evaluations, experienced observers stated that the radiograph was assessable. Inexperienced observers evaluated the radiographs as being assessable in only 46.5% of evaluations. Increased interobserver agreement on assessability of a radiograph did not increase the overall interobserver agreement in the diagnosis of hip dysplasia, nor did it result in consistent scoring of the hip status from that radiograph, despite a significant ( P <0.05) increase in agreement of FCI scoring with an increasing agreement on assessability at a one to five ratio in the experienced group. The inconsistent evaluation of radiographic quality, as well as the inconsistent evaluation of the hip quality, caused differences in diagnosing hip dysplasia and FCI scoring in the same dog ranging from excellent hips to moderate hip dysplasia. Therefore, the credibility of the FCI screening method for canine hip dysplasia, using the standard hip-extended radiographic view, as currently applied in most European countries, is questionable.     

CHANGES IN ECHOCARDIOGRAPHIC VARIABLES OF LEFT VENTRICULAR SIZE AND FUNCTION IN A MODEL OF CANINE NORMOVOLEMIC ANEMIA

The objective of this study was to document changes in echocardiographic variables of left ventricular size and function noninvasively during acute normovolemic anemia. This model was developed as a pilot study with the purpose of providing baseline information to investigate the pathophysiology, and more specifically the effect on the heart, of canine babesiosis-induced anemia. The study group comprised of 11 mature healthy Beagle dogs that weighed between 9 and 15 kg. Severe normovolemic anemia was induced over a 3-4-day period by serial bleeding while maintaining normovolemia by autotransfusing plasma and infusing crystalloids. The dogs were then allowed to recover. Preanemic (mean Hct 46.7%, standard deviation [SD] 2.4%) echocardiographic variables of left ventricular performance (Fractional shortening, ejection fraction, end-systolic and end-diastolic ventricular volumes, cardiac index, and heart rate) were compared with those in the severely (mean Hct 15.3%, SD 1.1%), moderately (Hct mean 24.7%, SD 1.5%), and mildly (mean Hct 33.5%, SD 2.5%) anemic states, and between the anemic states. With the exception of end diastolic volume, there was a statistically significant (P < 0.05) increase in all variables in the severely anemic state vs. the preanemic and the mild and moderate anemic states. In concordance with previous invasive models, a hyperdynamic state of the left ventricle develops in response to experimentally induced acute canine normovolemic anemia in the conscious dog. Echocardiography has promise as a noninvasive technique of evaluating the cardiac changes in dogs having canine babesiosis.     

FOCAL INCREASED RADIOPHARMACEUTICAL UPTAKE IN THE DORSOPROXIMAL DIAPHYSEAL REGION OF THE EQUINE PROXIMAL PHALANX

The aims of this study were to establish the frequency of occurrence, intensity and symmetry of focal increased radiopharmaceutical uptake in the dorsoproximal aspect of the diaphysis of the proximal phalanx; to determine if this focal increased radiopharmaceutical uptake was related to age, height, gender, breed, bodyweight, or discipline of the horse, and if there was any relationship with lameness. Scintigraphic images from 690 horses were analyzed subjectively and objectively. Age, breed, discipline, height, weight, gender, and lame limb(s) or reasons for presentation were recorded for all horses. Univariate and multivariable logistic regression was performed to identify associations between available variables and focal increased radiopharmaceutical uptake. Focal increased radiopharmaceutical uptake was present in 17% of forelimbs and 7% of hindlimbs. It occurred most frequently in the forelimbs of older, taller, and heavier warmblood and warmblood cross dressage horses, and the hindlimbs of older, taller, and heavier showjumpers and dressage horses. It was usually bilaterally symmetrical and was not associated with lameness.     

Nuclear Power Plants and Residential Housing Prices

Nuclear power plants can theoretically influence property values through a number of different channels. The public perception of risk associated with the potential hazard from the operation of a nuclear reactor and the storage of nuclear waste may lead to lower bids on properties in close proximity to the plant. In contrast, workers at the plant may be less concerned with any potential hazards, and may actually value being in proximity to the workplace. Hence, one cannot a priori sign the distance gradient of homes in the vicinity of a nuclear power plant. In this study, a hedonic model coupled with geographic information system (GIS) techniques is used to estimate housing price surfaces around two nuclear power plants in California. The use of GIS software allows more potential influences to housing prices to be accurately incorporated than previously included in hedonic studies. Based on the evidence from the plants chosen, these findings do not support the contention that negative imagery surrounding nuclear power plants or stored nuclear waste has a significant detrimental influence on residential home prices in the immediate vicinity of these facilities.     

DEEP DIGITAL FLEXOR TENDONITIS IN THE EQUINE FOOT DIAGNOSED BY LOW-FIELD MAGNETIC RESONANCE IMAGING IN THE STANDING PATIENT: 18 CASES

Injury to the distal aspects of the deep digital flexor tendon (DDFT) is an important cause of lameness in horses. The purpose of this study was to review the magnetic resonance imaging (MRI) findings of 18 horses affected by DDFT injuries in the foot. The MRI was performed with the horses standing using an open low-field (0.21 T) MRI scanner. The results were compared with those previously reported for horses using high-field MRI. Eighteen of 84 horses (21%) with undiagnosed forefoot pain were found to have lesions affecting the DDFT. The history, clinical findings and results of radiography, diagnostic ultrasonography and nuclear scintigraphy of these horses were reviewed. The duration of lameness ranged from 1 to 12 months, and the severity varied from 1/10 to 6/10. Fifteen horses had unilateral lameness (right fore in nine, left fore in six), whereas three horses were bilaterally foreleg lame. Radiological changes, considered of equivocal significance, were found in six of 18 horses. Ultrasonographic changes involving the DDFT were identified in only one of nine horses. DDFT lesions were detected in both T1- and T2-weighted MRI sequences. Four different types of lesions were identified: core lesions, sagittal splits, dorsal border lesions, and insertional lesions. Combinations of different lesion types within the same horse were common. The types and locations of the DDFT lesions were similar to those previously reported using high-field MRI. The use of low-field standing MRI avoids the necessity for general anesthesia and access to conventional high-field MRI scanners. However, studies comparing the results of standing low-field MRI with high-field MRI (and other imaging procedures) are required before the sensitivity and specificity of the technique can be assessed.     

ULTRASONOGRAPHY OF THE LIVER, SPLEEN, AND URINARY TRACT OF THE CHEETAH (ACINONYX JUBATUS)

Diseases of the abdomen of the cheetah (Acinonyx jubatus) include those affecting the liver, spleen, and urinary tract. The most common diseases of captive-bred cheetah are gastritis, gastric ulceration, glomerulosclerosis, and hepatic veno-occlusive disease, and are the most frequent causes of mortality in these animals. The purpose of this study was to describe the ultrasonographic anatomy of the normal liver, spleen, kidney, and urinary bladder of the anesthetized captive-bred cheetah. Twenty-one cheetahs were examined. Eight of the 21 animals had subclinical evidence of either gastritis or chronic renal disease. The ultrasonographic appearances of the liver, gall bladder, common bile duct, and spleen were evaluated and various measurements made. Statistical analyses of the measurements were performed on all the healthy and subclinically ill animals taking sex, age, mass, and anesthetic protocol into account. There were no significant differences in any parameters between the healthy and subclinically ill animals (P > 0.25) and data were combined for statistical analyses. The mean mass was 41.1kg ( +/- 8.8) and the mean age was 5.0 years (+/- 2.2). The mean thickness of the liver medial to the gall bladder was 67.0 mm (+/- 14.8) and the liver was within the left costal arch in 75% of animals, extended caudal to the right costal arch in 50% of animals for an average of 30 mm, and extended caudal to the sternum in 63% of animals for an average of 32.5 mm. The maximum mean hepatic vein diameter at the entrance to the caudal vena cava was 8.6 +/- 2.8 mm; the mean diameters of the portal vein at the hilus and that of the caudal vena cava as it entered the liver were 7.5 +/- 1.6 and 9.9 +/- 4.1 mm, respectively. The mean diameter of the caudal vena cava was significantly affected by the type of anesthetic used (P < 0.10). The mass of the animals was significant in explaining the variance in maximum portal vein diameters (P < 0.10). The mean maximum velocity of the hepatic vein flow at the entrance to the caudal vena cava was 25.3 +/- 2.8 cm/s (n=4), the hilar portal vein was 11.7 +/- 3.3 cm/s (n=7), and the caudal vena cava was 33.8 +/- 19.8 cm/s (n=5). The mean maximum gall bladder length and width, and the mean common bile duct diameters were 44.6 mm (+/- 10.4), 23.3 mm (+/- 5.0), and 8.1 mm (+/- 2.4), respectively. Age was significant in explaining the variance in gall bladder lengths (P<0.10). Urinary tract ultrasonography was performed only in animals that had normal urea and creatinine levels (n=13). Renal cortico-medullary distinction was present in all kidneys and a cortico-medullary rim sign was seen in 21 of 26 kidneys. Mean kidney length, height, and width was 63.9 +/- 5.7, 38.1 +/- 5.2, and 42.1 +/- 5 mm, respectively. The average resistivity index was 0.58 (n=5). Mean urinary bladder length, height, and width were 57.0, 19.2, and 34.9 mm, respectively.