Fig. 3. Sagittal T2-weighted magnetic resonance imaging scan obtained approximately 4 weeks after replacement of intrathecal analgesic with saline. The mass anterior to the spinal cord has resolved almost completely; only a thin layer of residual tissue remains. The spinal cord is relieved of compression, and only minor distortion of the anterior aspect of the thecal sac remains. The  arrowhead overlies the T11 vertebral body.