Endoscopic Evaluation of Angiogenesis in the Large Airways of Horses with Heaves Using Narrow Band Imaging.
BACKGROUND
Heaves is a severe debilitating condition of horses, characterized by lower airway inflammation and permanent structural changes of the bronchial wall. Chronic inflammation promotes the formation of new vessels, a phenomenon known as angiogenesis. Narrow band imaging (NBI) endoscopy is a noninvasive technique that enhances the visualization of submucosal vessels, and commonly is employed for the study of angiogenesis in human patients.


OBJECTIVES
Using NBI, we aimed to determine whether or not the central airways of horses with heaves undergo angiogenesis.


ANIMALS
Horses with heaves during exacerbation of the disease (n = 5) and healthy controls (n = 6).


METHODS
A library of NBI images was established from previously recorded videoendoscopies. Images were acquired by an operator blinded to horse ID. Images were obtained from 3 sites: 130 from the trachea (14 ± 9.3 [mean ± SD] images per horse with heaves and 10 ± 5.4 from controls; P = .45), 58 from the carina (5.4 ± 3.2 from horses with heaves and 5.2 ± 2.8 fromn controls; P > .99) and 167 from the intermediate bronchi (17.8 ± 6.7 from horses with heaves and 13 ± 5.6 from controls; P = .17). Using dedicated stereology software (NewCAST, Visiopharm; Denmark), the volume density of superficial and deep vessels was calculated blindly by point counting at each site for all horses.


RESULTS
In the trachea, the volume density of superficial vessels was increased in horses with heaves compared to controls (P = .02). No difference was found between groups for the volume density of both superficial and deep vessels at the carina or intermediate bronchi.


CONCLUSION AND CLINICAL RELEVANCE
NBI imaging of the airways was easily performed in standing sedated horses.
['Herteman|N|N|', 'Bullone|M|M|', 'Lavoie|J-P|JP|']
D056151:Airway Remodeling D000818:Animals D001980:Bronchi D016022:Case-Control Studies D006734:Horse Diseases D006736:Horses D008173:Lung Diseases, Obstructive D009389:Neovascularization, Pathologic
Blood vessels Equine Asthma Recurrent airway obstruction