TRACHEAL AND LARYNGEAL TUMORS IN THE DOG AND CAT: LITERATURE REVIEW AND 13 ADDITIONAL PATIENTS

Primary tumors of the larynx or trachea are uncommon in the dog and cat. In a review of the English language literature, description of 65 such patients were found. In a search of the Veterinary Teaching Hospitals of the University of Pennsylvania and North Carolina State University, an additional 13 previously unreported patients were identified, bringing the total to at least 78. Of these 78, there have been 16 canine tracheal, 7 feline tracheal, 34 canine laryngeal and 21 feline laryngeal tumors. In the canine and feline trachea, osteochondroma and epithelial malignancies, respectively, appear to be the most common. Epithelial malignancies appear to be the most common tumor of the canine larynx whereas lymphosarcoma appears to be the most common feline laryngeal tumor. In patients described herein, tumors produced clinical signs consistent with airway obstruction. Voice alteration was common in patients with laryngeal tumors. Patients were middle‐aged to older, except for dogs with osteochondroma. This compares favorably to historical data. All tumors in this study were readily seen radiographically, with most laryngeal and tracheal tumors appearing as masses within the lumen of the airway. Mineralization was uncommon except for canine osteochondromas. Feline laryngeal tumors in this study appeared as generalized laryngeal thickening rather than as a distinct mass. Response of canine and feline tracheal and laryngeal thickening rather than as a distinct mass. Response of canine and feline tracheal and laryngeal tumors to treatment can not be adequately assessed from available data. Benign tumors of the larynx or trachea may be amenable to complete excision. Neoplastic lesions must be differentiated from polyps or abscesses within the upper airway as these may appear radiographically identical to primary tumors. This can be achieved by endoscopic evaluation and biopsy of airway masses before formulating a prognosis. Copyrigh

Genetic improvement of hip-extended scores in 3 breeds of guide dogs using estimated breeding values: Notable progress but more improvement is needed.

Two hip quality phenotypes-a hip-extended score assigned by a board certified radiologist and the PennHIP distraction index-were analyzed to estimate genetic parameters and to calculate estimated breeding values used for selecting replacement breeders. Radiographs obtained at 12-18 months of age were available on 5,201 German Shepherd Dogs, 4,987 Labrador Retrievers and 2,308 Golden Retrievers. Obtained by fitting a two-trait model using Bayesian techniques, estimates of heritability for the hip-extended score were 0.76, 0.72, and 0.41 in German Shepherd Dogs, Labrador Retrievers, and Golden Retrievers, respectively, while estimated heritabilities for distraction index were 0.60, 0.66 and 0.59, respectively. Genetic correlations between the two hip quality measures were -0.28 in German Shepherd Dogs, -0.21 in Labrador Retrievers, and -0.29 in Golden Retrievers. Genetic selection for improved hip quality based upon the hip extended score phenotype began in 1980. Among first generation puppies, 34% of 273 German Shepherd Dogs, 55% of 323 Labrador Retrievers, and 43% of 51 Golden Retrievers had an Excellent hip extended score. After 8 generations of selection, mostly based on estimated breeding values derived from the hip extended score, over 93% of 695 German Shepherd Dogs, 94% of 528 Labrador Retrievers, and 87% of 116 Golden Retrievers received an Excellent hip extended score. With respect to PennHIP distraction index values among these same dogs, median values were at or above 0.30 for all 3 breeds meaning that half or more of dogs possessing the Excellent hip-extended-score phenotype remained susceptible to developing the osteoarthritis of canine hip dysplasia. Genetic improvement of the hip-extended-view phenotype to its desired biological endpoint left a surprising proportion of dogs expressing sufficient joint laxity to place them in an osteoarthritis at-risk state as they age. Only by directly applying selection pressure to reduce distraction index was marked reduction in joint laxity noted

Comparative evaluation of an ultraviolet and an orthochromatic rare-earth imaging system for veterinary radiography

The relative quality and speed of a new ultraviolet-emitting screen, ultraviolet-sensitive film rare-earth system (DuPont Ultra-Vision®) was compared to an orthochromatic rare-earth system (Kodak Lanex®) in a clinical trial. Seven different sets of radiographs of a human foot phantom, or actual canine anatomical structures (tarsus, pelvis, skull, chest, abdomen) were evaluated independently by radiologists, radiology residents and technicians who were unaware of the screen/film combinations used. The 400-speed, Ultra-Vision® Rapid/UVG screen/film combination produced supervisor image detail compared to blue/green emitting 400 and 200-speed screen/film combinations. The image detail of the Ultra-Vision® Rapid/UVG system was nearly equivalent to that produced using a 100-speed, fine-detail blue/green emitting screen/film combination. A 200-speed Ultra-Vision® system was also tested and produced thoracic and abdominal radiographs of equivalent to slightly supervisor quality than those produced using blue/green emitting system