NUCLEUS PULPOSUS PULMONARY-EMBOLISM - A CASE-REPORT

Study Design. This postmortem case report describes nucleus pulposus p ulmonary embolism occurring in a human. Objectives. Clinical, patholog ic, and pathogenetic features of the case are discussed. Reference is made to warnings in the literature stressing the importance of avoidin g, during radiologic procedures, any possibility of intrathecal ingres s of iodinated, ionic, hyperosmolar contrast material. Summary of Back ground Data. Various tissues have been implicated as pulmonary emboli in humans. Nucleus pulposus has been reported to embolize to spinal co rd vessels in animals and humans and to embolize to the lungs in two a nimal species. This is the first report of nucleus pulposus pulmonary embolism in a human. Methods. A patient with refractory low back pain was admitted for lumbar discography using diatrizoate meglumine, 52%, and diatrizoate sodium, 8%. Afterward, an ultimately fatal systemic re action began, among the symptoms of which were spasmodic extensions of the lower back and legs. Postmortem examination was performed. Result s. Nucleus pulposus pulmonary emboli were seen microscopically on rand om lung sections. The lumbar vertebral column grossly featured acute h erniations of disc material into vertebral marrow spaces; nucleus pulp osus was identified microscopically in these areas. Conclusions. We sp eculate that the spasmodic back extensions imposed compressive forces on vertebrae, causing nucleus pulposus to be extruded into vertebral m arrow sinusoids (thus creating emboli) and possibly causing these embo li to flow anteriorly into the anterior external vertebral plexus, whi ch resulted in pulmonary emboli exclusively with no spinal cord emboli .