Ossification of the Posterior Longitudinal Ligament
46 years old presents with neurological symptoms from upper extremities. MRI shows significant cervical spinal stenosis that is due to Ossification of the Posterior Longitudinal Ligament (OPLL). This is know to progress even after laminoplasty. Surgeons are interested in staging of OPLL.
Therefore we perform CT that helps in evaluation of calcifications. Staging of OPLL depends on extension of calcifications, if those are interrupted, continuous or mixed. In this case calcifications are interrupted - type B. This has prognostic value concerning the progress of the disease after laminoplasty.
See also staging and overview in this excellent article:
Yoshiharu Kawaguchi - Progression of Ossification of the Posterior Longitudinal Ligament Following en Bloc Cervical Laminoplasty