Magnetic resonance imaging enhancement of intervertebral disc disease in 30 dogs following chemical fat saturation

Abstract

To describe the patterns of enhancement of extradural intervertebral disc on chemically fat saturated gadolinium-enhanced magnetic resonance images and to investigate the clinical and pathological associations with enhancement. Medical records and magnetic resonance images were reviewed from 30 dogs with histopathologically confirmed disc disease and enhancement on a T1-weighted postcontrast fat saturated sequence. Median duration of neurological signs was 4 days and the most common grade of severity was II, seen in 46·6% of dogs. Homogeneous, heterogeneous and peripheral patterns of disc enhancement were described, with peripheral enhancement most commonly identified (57% of dogs). There were no clinical or pathological differences between the dogs with each of the patterns. The mean signal intensity of a region of interest within the extruded disc material and contrast-to-noise ratio of the disc material were significantly higher on postcontrast T1-weighted fat saturated images (P=<0·0001 each). The use of fat saturated gadolinium-enhanced magnetic resonance imaging can detect enhancement of extradural disc material. Patterns of enhancement are not associated with the clinical presentation or pathological features.