Magnetic resonance imaging appearances of different discovertebral lesions.

Magnetic resonance imaging (MRI) is not only an excellent imaging modality for the demonstration of morphological changes but is also capable of providing pathophysiological and pathoanatomic information about various spinal diseases. Different techniques offer opportunities to demonstrate the degree of water content, the vascularity of tissue components, the accumulation of fat, and new bone production. Thus MRI closely reflects the initial phase as well as the progression of pathoanatomic changes during the evolution of a disease. Due to the high sensitivity of MRI, abnormalities are often established at an early stage of discovertebral disease, when etiological diagnosis may be difficult. The specificity of MRI findings lags behind its sensitivity; similar changes can be demonstrated in etiologically different disease entities, which reflects the limited reactive possibilities of the osteoarticular system. In fact, the MRI morphological and signal intensity features of different discovertebral lesions are commonly determined more by their location and by the reactive capabilities of disc and bone than by their etiology. Early and exact MRI differentiation of various discovertebral lesions is of the utmost clinical importance for prompt institution of appropriate therapy.