Magnetic resonance imaging (MRI)

Magnetic Resonance Imaging (MRI) works in a completely different way than CT. It produces images based on the interaction between a strong magnetic field, radiofrequency impulses and tissue protons.

The contrast between tissues is not constant: water, for example, yields a signal that is white (hyperintense) or black (hypointense) in the images, according to the radiofrequency impulse sequence used. The different contrasts are used to study the normal and abnormal anatomy of patients; the combination of different sections and sequences is necessary to achieve full diagnostic information.

It is possible to obtain sections in every different plane of the animal: sagittal, transversal, dorsal and on several obliquity grades. The MRI exam lasts from 45 to 90 minutes. Time depends on the number of sequences required for a specific exam. To perform MRI exams, as for CT, pets need to be under general anaesthesia, to avoid all movements. The excellent contrast between soft tissues makes the MRI the best exam for assessing the brain and the spinal cord. It is also very sensitive to study neoplastic lesions, both in soft tissues and in the skeletal system.

In radiology, MRI is one of the most sophisticated and expensive devices. The Diagnostic Imaging depertment of the Istituto Veterinario of Novara has a MRI particularly appropriate for studies in small animals.

 

Modern technological devices