Interpreting radiographs 6: Radiology of the equine head (Part 2)

Abstract

Summary The value of radiology as part of an examination of the equine head is emphasised and the radiological appearances of more commonly occurring conditions are described. Even the normal anatomy of this complex site is subject to great variation and the aspiring radiologist should, therefore, have a good knowledge of the possible normal variations. A flexible approach must be used rather than a limitation to one or two ritual projections. The use of contrast media, wherever it might be useful, is advocated so that the maximum amount of information may be obtained from each examination. Finally, emphasis is laid on the fallibility of radiology when used in isolation and its use to complement other investigative procedures, such as endoscopy, is encouraged.

The role of head computed tomography in equine practice

“…The most prevalent condition was dental disease. Radiographic (Wyn‐Jones ; Gibbs and Lane ; Townsend et al . ) and CT (Henninger et al .…”

“…Diseases involving the head are frequently encountered in horses and require imaging studies for further work‐up (Tucker and Farrell ). Historically, radiography has been the primary imaging technique for assessing the skull, nasal cavity, dental structures and paranasal sinuses (Wyn‐Jones ,b; Tremaine and Dixon ). However, the anatomic complexity and superimposition of the osseous, dental and soft tissue structures complicate radiographic interpretation (Tucker and Farrell ).…”

Acquisition and interpretation of radiographs of the equine skull

“…Fractures of the rostral mandible are the most common jaw fracture and are typically seen in young horses, often as a result of biting onto a fixed object, such as stall door, and then becoming startled and pulling back, fracturing the alveolar bone (Wyn‐Jones ; Greet and Ramzan ). Rostral maxilla fractures are less common.…”

“…). Other reported indicators are widening of the periodontal space, changes in the shape or an indistinct appearance of the tooth root (Wyn‐Jones ; Gibbs and Lane ) ( Fig ). Occasionally small root fragments can be visualised.…”

Clinically significant, nontraumatic, degenerative joint disease of the temporomandibular joints in a horse

“…Long‐standing cases may develop atrophy of the masseter muscles, bony enlargement of the TMJ, weight loss and dental malocclusions (Baker ; Nagy and Simhofer ). The small size of the joint space and the complexity of overlapping anatomic structures in the equine head can complicate the interpretation of radiographs of the TMJ (Wyn‐Jones ). As such, newer (tangential and rostral 45° ventral‐caudodorsal oblique), projections of this region have recently been described (Ramzan et al .…”