Computed tomography and magnetic resonance diagnosis of variations in the anatomical location of the major salivary glands in 1680 dogs and 187 cats

Abstract

Durand, A., Finck, M., Sullivan, M., and Hammond, G. (2016) Computed tomography and magnetic resonance diagnosis of variations in the anatomical location of the major salivary glands in 1680 dogs and 187 cats. Veterinary Journal, 209, There may be differences between this version and the published version. You are advised to consult the publisher's version if you wish to cite from it.http://eprints.gla.ac.uk/118346/ OBJECTIVE:To assess the ventro 20° rostral-dorsocaudal oblique (V20R-DCdO) projection for canine nasal disease as an alternative to the dorsoventral intra-oral (DVIO) view. METHODS:Thirty-one dogs with nasal disease underwent radiography and CT with final diagnosis achieved through rhinoscopy, biopsy or cytology. Three independent observers, blinded to diagnosis, reviewed the nasal radiographs on two separate occasions. Intra-and inter-observer agreement and level of confidence on radiographic diagnosis was evaluated and radiographic diagnosis was compared with CT and definitive diagnosis. RESULTS:The V20R-DCdO projection of canine nasal cavities was feasible in anaesthetised patients and gave diagnostic quality images in most dogs. Assessment of this view showed moderate to substantial agreement with CT diagnosis but gave lower confidence in diagnosis. Interpretation of this radiographic projection had substantial to almost perfect repeatability but moderate reproducibility. CLINICAL SIGNIFICANCE:The V20R-DCdO projection may be used as a valuable initial screening tool for canine nasal pathology in practices without access to advanced imaging, although CT is still likely to provide greater diagnostic information.

Anatomic and magnetic resonance imaging features of the salivary glands in the dog

“…In this study, the images were obtained using a high‐field MRI magnet that showed excellent visualization of the normal appearance of the salivary glands, and associated anatomical structures. Similar results have been observed in dogs using high‐field (Durand et al., ) and low‐field protocols (Kneissl & Probst, ; Weidner et al., ). The main limitations of low‐field MR imaging are the lower signal‐to‐noise ratios, poor spatial resolution, and motion artifacts (Tavernier & Cotten, ).…”

“…Exploration and clinical evaluation of the salivary glands in the dog is laborious because of their anatomical complexity, which challenges the diagnosis of morphological changes simply via physical examination. Diagnostic imaging techniques such as conventional sialography (Tadjalli, Dehgani, & Basiri, ), ultrasound (Lenoci & Ricciardi, ), CT (Durand et al., ; Kneissl et al., ), and MRI (Durand et al., ; Weidner et al., ) have been used to evaluate the salivary gland and their ducts in dogs. In some cases, radiography may be sufficient to make a diagnosis when the clinical signs and physical examination give detailed information on the disorder (Perez‐Ecija, Estepa, & Mendoza, ); however, if radiographic assessment is inconclusive, then more advanced imaging techniques are necessary.…”

“…Ultrasonography offers precise identification of the salivary glands and a detailed morphologic evaluation of the salivary glands, and CT is particularly beneficial to its good anatomic resolution, soft tissue contrast, and morphologic detail of these glands (Lenoci & Ricciardi, ). However, MR imaging is highly recommended for visualization of the salivary glands and is now the preferred imaging method for the evaluation of diseases of salivary glands (Durand et al., ).…”

“…However, during the last decades, veterinary medicine in small animals has experienced a continuous advance with respect to modern imaging techniques that offer better visualization of tissues and structures to provide more accurate diagnoses. Thus, some recent work (Durand, Finck, Sullivan, & Hammond, ; Kneissl, Weidner, & Probst, ; Weidner et al., ) has analysed the normal appearance and location of the salivary glands in the dog via magnetic resonance imaging (MRI) and computed tomography (CT). MRI is the most appropriate technique for study of the salivary glands because it offers soft tissue contrast without ionizing radiation, and it can differentiate the glandular tissue from adjacent muscles.…”

“…This offers more detailed anatomical location (Dennis, ). However, studies carried out by MRI (Durand et al., ; Weidner et al., ) have not yet demonstrated all of the large canine salivary glands. Thus, the aim of this study was to perform an anatomical and sectional study of the head where the situation and topographic relationships of the salivary glands of the dog were analysed.…”