The carnassial teeth in the cat are the same as in the dog: the last upper premolar and the first lower molar. In the cat, the roots of the upper fourth premolar extend into the wall of the orbit. Figure 2-3 identifies these bones diagrammatically. The important larger bones of the skull that are visible radiographically are the incisive, nasal, maxillary, lacrimal, frontal, zygomatic, pterygoid, sphenoid, parietal, temporal, and occipital bones. Many are not identifiable with survey radiographs, and most fuse with adjoining bones precluding specific delineation. This is discussed in the “Dentition” section.Īpproximately 50 bones, many of which are paired, compose the skull. This is particularly important when there is no obvious unilateral disease. This allows correct identification of surfaces projected in profile. In addition, oblique views are impossible to interpret correctly unless a readily understandable external radiographic marking system is used. Oblique views should not be used to replace the standard views because standard views often provide information that allows more effective interpretation of oblique views. They should, however, always be acquired in concert with standard lateral and dorsoventral (or ventrodorsal) views. TMJ, Temporomandibular joint.Īdditional views of the skull are often acquired depending on the region of interest. B, Dorsoventral radiograph of an 18-year-old domestic shorthair cat. The osseous tentorium, which separates the caudal aspect of the cerebrum from the rostral aspect of the cerebellum, is particularly well-developed in cats compared to dogs. Brachycephalic describes breeds with short and wide heads, such as Boston terriers and Pekingese.Ī radiographic study of the skull should always include a lateral and dorsoventral (or ventrodorsal) view (Figures 2-1 and 2-2).įigure 2-2 A, Lateral radiograph of a 3-year-old domestic shorthair cat. The term mesaticephalic describes breeds that have heads of medium proportions, such as German shepherds, beagles, and setters. The term dolichocephalic describes long, narrow-headed breeds, like collies and wolfhounds. Various measurement parameters are used to group dogs based on skull morphology. The skull varies more in size and shape among domestic dogs than in any other mammalian species. Taking the time to ensure adequate patient restraint and optimal positioning significantly increases the chances of obtaining meaningful information. Because the skull is so complex, standardization of views becomes more important than in any other location.
Poorly positioned skull radiographs are particularly challenging to interpret and usually have no diagnostic value. However, well-positioned radiographs with good detail and contrast can provide information that can help in directing appropriate patient management or selecting the best alternative imaging modality.Īlthough it is often more convenient to acquire radiographs of the skull with the patient conscious or minimally sedated, this rarely results in well-positioned radiographs. Imaging the skull is much better suited to the cross-sectional modalities of computed tomography and magnetic resonance imaging, which solve the issue of superimposition and are characterized by superior contrast resolution. Superimposition of the many complex osseous structures limits the usefulness of radiography. It does not store any personal data.The skull is the most complex and specialized part of the skeleton it is a challenging region to evaluate with conventional radiography. The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. The cookie is used to store the user consent for the cookies in the category "Performance". This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other. The cookies is used to store the user consent for the cookies in the category "Necessary". The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". The cookie is used to store the user consent for the cookies in the category "Analytics". These cookies ensure basic functionalities and security features of the website, anonymously.
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