Objective—To ascertain the frequency of ultrasonographic identification of liver at sites recommended for blind percutaneous liver biopsy in middle-aged horses and to determine whether the liver is obscured by other organs or too thin for safe sample collection at recommended locations.
Design—Prospective case series.
Animals—36 healthy middle-aged (between 6 and 18 years old) Quarter Horses or Quarter Horse crosses.
Procedures—Blood samples were collected from each horse and submitted for evaluation of liver function. Horses with any indication of liver dysfunction on serum biochemical analysis were excluded. The region just below a line drawn between the dorsal aspect of the tuber coxae and the point of the elbow joint in the right 11th, 12th, 13th, and 14th intercostal spaces (ICSs) was imaged by ultrasonography for the presence of liver. In each ICS, liver thickness and whether there was partial obstruction in viewing the liver caused by other abdominal or thoracic organs were recorded.
Results—39% (14/36) of horses had liver imaged on ultrasonographic examination in all of the 11th to 14th ICSs. None of the 36 horses had liver of adequate thickness (ie, liver thickness ≥ 3.5 cm) for biopsy in all of the imaged ICSs. For 22 horses in which the liver was not visible on ultrasonographic examination of an ICS, lung was imaged instead in 12 (55%) horses, intestine in 8 (36%), and both intestine and lung in 2 (9%).
Conclusions and Clinical Relevance—On the basis of the results of this study, the practice of blind percutaneous liver biopsy in horses is not recommended because of the risk of serious complications.
Objective—To characterize the associations between clinical signs of nasopharyngeal cicatrix syndrome (NCS) and endoscopic findings in horses.
Design—Retrospective, case-control study.
Animals—239 horses (118 case horses and 121 control horses).
Procedures—Medical records of horses that had an endoscopic evaluation of the upper airway performed between January 2003 and December 2008 were reviewed. Clinical signs and the appearance and anatomic locations of lesions identified during endoscopic evaluation were reviewed and recorded for each horse. The associations between clinical signs and endoscopic findings were evaluated by the use of a prospective logistic model that used a Bayesian method for inference and was implemented by a Markov chain Monte Carlo method.
Results—Nasal discharge was associated with acute inflammation of the pharynx and larynx. Exercise intolerance was associated with circumferential pharyngeal lesions. Respiratory noise was associated with chronic scarring of the pharynx, a combination of pharyngeal and laryngeal scarring, and circumferential scarring of the pharynx. Respiratory distress was associated with acute inflammation of all portions of the airway, especially when there was preexisting scarring and narrowing of the airway by ≥ 50%. Cough did not have any significant association with NCS, compared with results in control horses.
Conclusions and Clinical Relevance—Associations between the endoscopic appearance of NCS lesions and relevant clinical signs will help practitioners identify horses with NCS and allow them to select appropriate treatment.
Objective—To determine risk factors associated with the development of nasopharyngeal cicatrix syndrome (NCS) in horses.
Design—Retrospective case-control study.
Animals—242 horses referred for endoscopic evaluation of the upper portion of the respiratory tract (121 horses with NCS and 121 control horses).
Procedures—Medical records of horses that had an endoscopic evaluation of the upper airway performed between January 2003 and December 2008 were reviewed. Signalment, housing management, and season of evaluation were recorded and reviewed for each horse. The associations between clinical signs and endoscopic findings were evaluated by the use of a prospective logistic model that included a Bayesian method for inference.
Results—Breed and sex had no significant effect on the risk of having NCS. The risk that a horse had NCS increased significantly with age. Exclusive housing in a stall was protective against the development of NCS. In addition, the amount of pasture turnout had a dose-related effect, with exclusive pasture turnout positively correlated with increased risk of developing NCS, compared with a mixture of pasture turnout and stall confinement. Horses were significantly more likely to be evaluated because of clinical signs of the syndrome during the warm months of the year.
Conclusions and Clinical Relevance—The risk factors for NCS identified in this study may support chronic environmental exposure to an irritant or infectious agent as the cause of NCS. Information gained from this study should be useful for investigating the cause of NCS.