Gastric emptying in cats using foods varying in fiber content and kibble shapes.

The purpose of this study is to evaluate the influence of kibble shape and fiber content of commercial dry foods on gastric emptying in healthy cats. Eight healthy cats were used to evaluate four different diets which varied in shape of kibble (round versus triangle) or fiber content (low versus high). Diets were labeled with 99mTc-mebrofenin and gastric emptying was evaluated with nuclear scintigraphy. There was a significant difference between the kibble shapes at both T50 and T20. The triangle shaped kibble required significantly longer time than the round kibble to reach T50 (P = 0.02) and T20 (P = 0.001). Diet fiber content did not have a significant influence on T50, and T20. The influence of caloric and water intake was assessed with division of cats into high, medium, and low intake groups. The caloric intake had its main effect at T50 with the lowest quartile of caloric intake requiring significantly less time to reach T50 than the middle group and upper quartile (P = 0.05). Water intake did not have a significant effect on gastric emptying in this study. There was no relationship or correlation between the surface area of the food (cm2/kg) and T90, T50, and T20.

Equine nuclear scintigraphy. Indications, uses, and techniques.

The demand for advanced and correlative imaging methods in equine medicine is growing. Scintigraphy can provide unique information about the physiologic status of an animal that cannot be discerned by other imaging modalities.

Radiographic and ultrasonographic findings of liver lobe torsion in a dog.

A twelve-year-old neutered male beagle presented for a cranial abdominal mass. The results of physical examination, laboratory tests, radiography, and ultrasonography are presented. A torsion of the quadrate lobe of the liver was diagnosed at surgery and confirmed by histopathology. A brief discussion of liver lobe torsion is presented.

Radiographic findings of canine dysautonomia in twenty-four dogs.

Canine dysautonomia is an idiopathic condition resulting in loss of autonomic nervous system function. Recently, the prevalence of dogs diagnosed with dysautonomia in the mid-western United States has increased. In this study the medical records and radiographic findings in 24 dogs with dysautonomia were reviewed. A diagnosis of dysautonomia was made in 17 (71%) of the dogs in this study by postmortem examination, the remaining 7 (29%) dogs were diagnosed pharmacologically. The radiographic findings supportive of dysautonomia include aspiration pneumonia, megaesophagus, or a distended stomach, small bowel, or urinary bladder. In some instances, the disease radiographically mimicked other disorders of the gastrointestinal tract, including mechanical obstruction.

Diagnostic imaging of lameness in small animals.

The demand for advanced diagnostic imaging procedures such as nuclear scintigraphy, ultrasonography, computed tomography, and magnetic resonance imaging has increased dramatically over the past 10 years. Veterinarians, seeking to improve their diagnostic capabilities and clients willing to pursue "best medicine" have driven this demand, resulting in installation of advanced imaging facilities at most academic and private referral practices. Knowledge of potential benefits of various modalities will allow the veterinarian to optimize his or her use of diagnostic imaging in his or her own practice or in a referral practice.

Case examples demonstrating the clinical utility of obtaining both right and left lateral abdominal radiographs in small animals.

Seven case examples are presented which illustrate the utility of using both right to left and left to right laterolateral abdominal radiographs (left lateral and right lateral recumbent radiographs, respectively) when evaluating gastrointestinal disease. These cases demonstrate the benefits of obtaining both lateral abdominal radiographs in disease of the stomach, small intestine, and large intestine. A review of the literature concerning this technique is provided.

Compression radiography: an old technique revisited.

Five case examples are provided to illustrate the use of compression radiography in the dog and cat. Abdominal compression radiography provides for evaluation of the size, shape, location, and opacity of a specific area without the degree of superimposition encountered with survey radiographs. The following cases illustrate compression techniques of the intestinal tract, uterus, kidney, bladder, and spleen. A review of the technique as well as a discussion of the advantages and limitations are presented.

Effects of external thermal manipulation on laminar temperature and perfusion scintigraphy of the equine digit.

AIMS: To assess the effects of external thermal manipulation on the soft-tissue and vascular perfusion of the equine digit using nuclear scintigraphy and documented tissue temperatures. METHODS: Six horses were used in a randomised crossover design. Each horse was treated with external heat (47 degrees C) or external cold (4 degrees C) applied to a digit for 30 minutes. The opposite front foot was untreated and used for control measurements. Nuclear scintigraphy was performed before, during, and after therapy to assess vascular and soft-tissue perfusion to the digit in response to therapy. Dorsal hoof wall laminar-tissue temperatures were recorded before, during, and after therapy using a thermistor. RESULTS: Treatment with topical cold therapy significantly decreased soft-tissue perfusion of the digit to 80.5% of the pre-cooled values. Conversely, the application of external heat significantly increased soft-tissue perfusion of the digit 25.1% above the pre-heated values. Vascular perfusion showed similar, but not statistically significant trends. External cold application to the digit caused a significant mean decrease in laminar-tissue temperatures of 11.6 degrees C during therapy, while external heat application to the digit caused a significant mean increase in laminar-tissue temperatures of 3.9 degrees C. CONCLUSION: The external application of heat and cold to the normal equine foot could effectively alter soft-tissue perfusion and laminar-tissue temperatures within 30 minutes of treatment. The application of hot water and ice water to the digit was a safe, well-tolerated, and economical therapy. CLINICAL RELEVANCE: Cooling the foot could decrease enzymatic reactions associated with laminitis, and warming could increase local perfusion when desired.

Pulmonary distribution of aerosolized technetium Tc 99m pentetate after administration of a single dose of aerosolized albuterol sulfate in horses with recurrent airway obstruction.

OBJECTIVE: To determine whether pulmonary distribution of aerosolized technetium Tc 99m pentetate is improved after inhalation of a single dose of albuterol sulfate in horses susceptible to recurrent airway obstruction (heaves). ANIMALS: 6 horses with heaves and 4 horses with normal respiratory tract function. PROCEDURE: Images were obtained during ventilation of horses at baseline (maximal change in pleural pressure during tidal breathing [deltaPpImax] >15 cm H2O) and after aerosolized albuterol sulfate (360 microg) administration, with a 24-hour washout period between experiments. The deltaPpImax was determined prior to the baseline scan, prior to albuterol sulfate administration, and 5 minutes after albuterol sulfate administration. Images were assessed by visual inspection (semi-quantitative scoring system) and histogram analysis. RESULTS: Images obtained from horses with heaves had nonuniform pulmonary distribution of radionuclide characterized by poor penetration in peripheral lung fields and excess deposition in large airways. Histogram analysis of images of the caudal portions of the lungs revealed nonuniform radionuclide deposition in horses with heaves and uniform radionuclide deposition in control horses. CONCLUSION: Administration of a single dose of aerosolized albuterol sulfate improved pulmonary distribution of aerosolized radiolabeled pentetate suspension in horses with heaves but did not alter pulmonary distribution in clinically normal horses. CLINICAL RELEVANCE: Precedent bronchodilator administration may improve pulmonary distribution of aerosolized, surface-active anti-inflammatory preparations.

Evaluation of solid phase radiolabels of dog food for gastric emptying.

99mTc-Pertechnetate, 99mTc-mebrofenin, 99mTc-disofenin, 99mTc-sulfur colloid, and 99mTc-Dowex resin beads were evaluated for in vitro stability as a label for both dry extruded, and canned dog food for gastric emptying scintigraphy. A sample of each radiolabeled diet was added to water, gastric juice, intestinal juice, or gastric juice followed by intestinal juice for in vitro digestion. After a 3-hour digestion period, tubes were centrifuged and percentage solid phase retention (%SPR) was calculated. The experiment was repeated three times over a 14-day period to minimize day-to-day variation. For dry dog food, 99mTc-mebrofenin and 99mTc-disofenin had similar %SPR in water (96 and 93%, respectively) and gastric juice (>95% each) and were significantly higher than other labels. For canned dog food, mebrofenin had a 91% SPR for the water or gastric juice digestions, and 99mTc-Dowex had a %SPR of >99%. 99mTc-mebrofenin and 99mTc-Dowex were also tested in vivo, where 99mTc-Dowex had poor stability, and 99mTc-Mebrofenin had excellent stability. 99mTc-Mebrofenin is a suitable label for dog food for gastric emptying scintigraphy.

Comparison of gastric emptying times in healthy cats simultaneously evaluated with radiopaque markers and nuclear scintigraphy.

Gastric emptying in 18 healthy cats was assessed simultaneously using scintigraphy and barium-impregnated polyethylene spheres (BIPS). Canned Prescription Diet Feline c/d (Hill's Pet Nutrition, Inc., Topeka, KS) labeled with 99mTc-disofenin (Hepatolite, DuPont Merck Pharmaceutical Co., Billerica, Mass.) was fed on four separate days. Scintigraphic images were obtained at time 0 and then every 30 minutes to 6 hours. On the fourth scan day, 30 small (1.5 mm) and 10 large (5 mm) BIPS (Chemstock Animal Health Ltd., Christchurch, New Zealand) were mixed with the labeled meal, and in addition to scintigraphy, radiographs were made at 60-minute intervals for 6 hours. Gastric emptying was 11 to 15% slower on the day of simultaneous radiography as compared with the 3 days when only scintigraphy was performed (p < or = .05). Percentage retention of 1.5 mm BIPS in the stomach was significantly greater than the percentage retained gastric activity at hours 1, 2, 3, 4, 5, and 6 (p < or = .05). BIPS were clustered in the pyloric region of the stomach by 3 hours in all cats. In 10/18 animals, all BIPS were retained in pyloric region of the stomach at 6 hours, despite observable decreased size of the gastric silhouette and < or =15% retained gastric activity. In conclusion, gastric emptying of 1.5-mm BIPS does not parallel gastric emptying of 99mTc-disofenin labeled canned Prescription Diet Feline c/d. Stress associated with radiography may delay gastric emptying. Diet type should be considered when evaluating clinical radiographic studies where BIPS have been used.

Scintigraphic evaluation of dogs with acute synovitis after treatment with glucosamine hydrochloride and chondroitin sulfate.

OBJECTIVE: To evaluate the effects of orally administered glucosamine hydrochloride (GlAm)-chondroitin sulfate (CS) and GlAm-CS-S-adenosyl-L-methionine (SAMe) on chemically induced synovitis in the radiocarpal joint of dogs. ANIMALS: 32 adult mixed-breed dogs. PROCEDURE: For 21 days, all dogs received a sham capsule (3 groups) or GlAm-CS (prior treatment group) in a double-blinded study. Unilateral carpal synovitis was induced by injecting the right radiocarpal joint with chymopapain and the left radiocarpal joint (control joint) with saline (0.9% NaCl) solution. Joints were injected on alternate days for 3 injections. After induction of synovitis, 2 groups receiving sham treatment were given GlAm-CS or GlAm-CS-SAMe. Another group continued to receive sham capsules (control group). Joint inflammation was quantified, using nuclear scintigraphy, before injection of joints and days 13, 20, 27, 34, 41, and 48 after injection. Lameness evaluations were performed daily. RESULTS: Dogs given GlAm-CS before induction of synovitis had significantly less scintigraphic activity in the soft-tissue phase 48 days after joint injection, significantly less uptake in the bone phase 41 and 48 days after joint injection, and significantly lower lameness scores on days 12 to 19, 23, and 24 after injection, compared with other groups. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of results of this study suggest that prior treatment with GlAm-CS for 21 days had a protective effect against chemically induced synovitis and associated bone remodeling. Prior treatment with GlAm-CS also reduced lameness in dogs with induced synovitis.

Effect of percutaneous endoscopic gastrostomy on gastric emptying in clinically normal cats.

OBJECTIVE: To assess the effect of percutaneous endoscopic gastrostomy (PEG) tube placement on gastric emptying in clinically normal cats. ANIMALS: 8 healthy adult 3- to 5-year-old cats. PROCEDURE: Cats were accommodated to the diet for 2 weeks prior to scintigraphy. Caloric needs were divided into 3 feedings/d. Food was withheld for 24 hours after tube placement, then was fed as a third of the caloric needs on day 1, two-thirds on day 2, and full caloric requirements thereafter. Gastric emptying was measured via nuclear scintigraphy. Labeled meals contained 111 MBq (3 mCi) of 99mTc-labeled disofenin. Sixty-second ventral scintigraphic images were acquired immediately, every 20 minutes for the first hour, then every 30 minutes for 4 hours after feeding. Each cat was evaluated 3 times prior to PEG tube placement. Cats were anesthetized, and 16-F mushroom-tipped Pezzar gastrostomy tubes were placed, using a video endoscope. Scintigraphy was repeated on days 1, 4, 7, 11, 14, and 21 after PEG tube placement. RESULTS: Gastric emptying was faster with a PEG tube in place. Percentage of retained gastric activity was significantly lower after PEG for 150, 180, 210, and 240 minutes versus time before PEG tube placement. CONCLUSION: Placement of a PEG tube does not delay gastric emptying in clinically normal cats. CLINICAL RELEVANCE: Gastric retention of food, vomiting, and aspiration pneumonia after PEG tube placement may not be related to delayed gastric emptying.

Scintigraphic assessment of gastric emptying of canned and dry diets in healthy cats.

OBJECTIVE: To characterize factors that affect solid-phase gastric emptying in healthy cats by use of nuclear scintigraphy and to assess differences in emptying patterns of dry and canned diets. ANIMALS: 20 healthy cats. PROCEDURE: 2 groups of 10 cats each were fed dry or canned diet for at least 2 weeks before scintigraphy was done. Diets were labeled with 99mTc-disofenin. After ingestion of labeled meals, scintigraphic images were obtained at 0, 15, 30, 45, and 60 minutes, then every 30 minutes to 6 hours. Gastric emptying scans were obtained 3 times for each cat for each diet, in a complete crossover design. The T90, T50, and T20 (times when 90, 50, and 20% of initial meal activity remained in the stomach, respectively) were derived from gastric emptying curves fit to nonlinear models. A mixed models approach was used for data analysis. RESULTS: Gastric emptying was well described by a nonlinear model. Meal size, water intake, and diet type significantly (P < 0.05) effected gastric emptying. The T90, T50, and T20 increased with meal size, regardless of diet type or water intake. Gastric emptying of a dry diet meal took significantly (P < 0.05) longer than that of an isocaloric meal of canned diet, except when meal size was small. Differences in gastric emptying of dry and canned diets varied with the phase (T90 vs T50 vs T20) of emptying. CONCLUSION: Water intake, meal size, and diet type significantly influence gastric emptying in healthy cats, and these factors must be considered in analysis of gastric emptying data.

Development of interactive patient-based multimedia computer programs in veterinary orthopedic radiology.

Three computerized multimedia programs on large and small animal veterinary orthopedic radiology were developed and implemented for the radiology curriculum as an alternative to traditional film-based laboratory learning. Programs utilized "hot words" (colored text words that displayed an overlaid image label that highlighted lesions) and interactive quizzes which responded appropriately to selected answers. "Hot words" helped students develop confidence in accurate lesion detection and the interactive quizzes transformed learning from a passive to an active process. Multiple examples were provided for reinforcement and concepts were incorporated from other clinical disciplines for curriculum integration. Programs were written using a presentation software program, Toolbook for DOS based platform, and contained radiographic images made by laser-scanning digitization. Multiple students could simultaneously access the programs through a network server. These pilot programs were implemented successfully and computerized multimedia presentation proved to be well suited to teaching radiology. Development of the programs required attention to a number of hardware, software, time and cost factors.

Magnetic resonance imaging of presumptive lumbosacral discospondylitis in a dog.

A three-year-old male Boxer dog had hyperesthesia, symmetrical epaxial, gluteal and hind limb muscular atrophy and rear limb ataxia. Neurological deficits included decreased conscious proprioception of the left hind limb, decreased withdrawal and increased patellar reflexes of both hind limbs. The dog had a urinary tract infection with positive culture for Staphylococcus intermedius. On survey radiography of the lumbosacral spine there was active bone proliferation spanning the L7 S1 intervertebral disc space with an epidural filling defect at the ventral aspect of the vertebral canal on epidurography. On magnetic resonance imaging (MRI), findings were similar to those described for human diskospondylitis including altered signal intensity and nonuniform contrast enhancement of the L7-S1 intervertebral disc, adjacent vertebral end plates and epidural and sublumbar soft tissues. Although skeletal radiography is usually sufficient to reach a diagnosis of discospondylitis, MRI of this patient made it possible to reach a presumptive diagnosis of discospondylitis prior to development of definitive radiographic abnormalities.