Application and indications of magnetic resonance imaging and computed tomography of the equine head

Abstract

The equine head is an anatomically highly complex area affected by a range of disorders, making the diagnosis of head conditions challenging. Imaging techniques play a crucial role in the diagnostic work-up of head disorders. Tomographic imaging methods, such as computed tomography (CT) and magnetic resonance imaging (MRI) are particularly useful in avoiding problems associated with superimposition of multiple structures in this highly complex region. Both techniques are becoming more widely available in equine medicine. However, the choice between CT and MRI for imaging the equine head is not always straightforward. Each modality has advantages and disadvantages in terms of practicality, costs and diagnostic value for particular problems. The aim of this review is to describe the application of CT and MRI for imaging the equine head and to provide a practical guide for their use in different anatomical structures and clinical indications. This should allow the equine practitioner to make an informed decision on which modality to choose. Magnetic resonance imaging Magnetic resonance imaging images are the result of the stimulation of magnetised tissues by radio waves and capturing the returning radio waves from the stimulated tissues. Depending on the type of emitted radio wave (duration,

Correlation between computed tomography, magnetic resonance imaging and cross‐sectional anatomy of the head of the guinea pig (Cavia porcellus, Linnaeus 1758)

“…On the contrary, MRI is a highly accurate imaging modality that provides excellent contrast of soft tissues using several different imaging sequences (Tucker & Farrell, 2001). MRI is the gold standard to examine the central nervous system and the extracranial soft tissues, such as the orbit, salivary glands, muscles, lymph nodes and blood vessels (Manso‐Díaz et al, 2021). It helps to evaluate soft tissue details, such as tumours, haemorrhage, inflammation and chronic diseases (Cole & Hespel, 2020).…”

Computed tomography and cross‐sectional anatomy of the head in the red fox (Vulpes vulpes)

“…Although CT is an X‐ray‐based imaging technique, it is superior than conventional radiography, because it is not affected by superimposition or the thickness of tissue. In addition, CT is considered as a standard imaging technique for assessing bones of skull, teeth, osseous canals, nasal passages, paranasal sinuses (Manso‐Díaz, Taeymans, García‐López, & Weller, 2019), orbit (Salgüero et al., 2015) and intracranial, as well as, extracranial lesions (Ohlerth & Scharf, 2007). Additionally, three‐dimensional (3D) reconstructed CT images are considered a valuable tool in the teaching and practice of medicine for the diagnosis of a variety of animal diseases (Keane, Paul, Sturrock, Rauch, & Rutland, 2017).…”

Application of Advanced Imaging Modalities in Veterinary Medicine: A Review

“…MRI investigations often comprise multiple different acquisition planes, including transverse, dorsal, and sagittal planes, in addition to varied sequences. 34 Thus, the application of MRI for imaging the different body regions and provides a practical guide for their use in different anatomical structures and clinical indications. This allows the veterinarian to make an informed decision on why to choose MRI.…”

“… 40 In the horse, MRI enabled detection of changes with an acute onset of severe unilateral forelimb lameness originating from the heel portion of the foot, and is the gold standard for studying orbit, lymph nodes, blood vessels, muscles, and salivary glands. 34 , 41 MRI also plays a crucial role in the diagnostic work-up of head disorders particularly useful in avoiding problems associated with superimposition of multiple structures in the head. 34 …”