Modern advances in diagnosis and surgery of guttural pouch disease

Enlargement caused by empyema and tympany (air engorgement), can be palpated externally, but endoscopy is the method of choice in most cases and can be used in the field. Endoscopy of the pharynx alone can provide some valuable information about guttural pouch distention and drainage, but the interior of the guttural pouch should be inspected to make the final diagnosis. Lateral radiographic projections of the guttural pouches demonstrate fluid lines, fractures and exostoses of the stylohyoid bone, radiopaque foreign bodies, and space-occupying masses. Air distention, as in tympany, can increase dimensions of the affected guttural pouch enormously. A dorsoventral or ventrodorsal projection is best used to image the stylohyoid bones and temporohyoid articulation. Computed tomography can provide an alternate imaging modality, especially for imaging of the stylohyoid bone, inner ear, and petrous temporal bone in cases of temporohyoid osteoarthropathy. Ultrasonography can be used to demonstrate soft tissue lesions in the guttural pouches, such as tumours or muscle damage and associated submucosal haemorrhage.
Magnetic resonance imaging can be used to evaluate masses impinging on the guttural pouch because it will provide useful information about the extent of soft tissue involvement in areas that cannot be examined by endoscopy. Examples include melanomas and other tumours of the lateral compartment and parotid gland. Time-of-flight magnetic resonance angiography (TOF-MRA) can be used to examine vessel morphology, symmetry, and size in the equine head and for preoperative planning or study of changes caused by neoplasia or guttural pouch mycosis. […]