A confusing magnetic resonance imaging observation complicating surgery for a dermoid cyst in a Rhodesian Ridgeback

Davies ES, Fransson BA, Gavin PR.

Vet Radiol Ultrasound 2004;45:307-309.

History

A 1-cm3 subcutaneous mass at the dorsal base of the neck was observed by the owners when the dog was 2 months old. One week prior to presentation the mass had swollen rapidly to approximately 8 cm in diameter. Three weeks before presentation, coinciding with the first estrous cycle, the owners noted an episode of hind limb weakness. No other sign of neurologic dysfunction had been exhib- ited.

Physical Examination

Physical and neurological examination was unremarka- ble except for an 8-cm nonpainful fluctuant mass, located subcutaneously in the cervical region approximately dorsal to cervical vertebrae 5 and 6. No cutaneous opening was noted.

Magnetic Resonance (MR) Imaging

A 1.0 T MR scannerôŹ°€ was used to image the dog in ster- nal recumbency utilizing a synergy spine coil. Sagittal and transverse images were acquired through the entire cervical area with T2-weighted (T2-W) and short time of inversion recovery (STIR) sequences. In addition, transverse images were acquired with T1 weighting and fluid attenuation in- version recovery (FLAIR). A venogram of the vessels dor- sal to the C7 to T2 spinal region was also performed using a 2-D time-of-flight technique.