Recurrent Craniocervical Pseudogout: Indications for Surgical Resection, Surveillance Imaging, and Craniocervical Fixation.

ABSTRACT

BACKGROUND: Calcium pyrophosphate dihydrate (CPPD) crystallization is known to occur in the spine, leading to the development of visible calcification as seen by imaging. Occasionally, the deposition of this material can lead to larger accumulations that are seen as masses in the articular processes, intervertebral discs, and posterior longitudinal ligaments. A particularly significant manifestation of this process is at the craniocervical junction, where symptomatic presentations can arise. CLINICAL PRESENTATION  A 74-year-old woman presented after several falls from standing, complaining of leg and arm weakness. Imaging revealed a mass arising from the C1-C2 articulation dorsal to the dens, extending to the clivus. The mass compressed the medulla and cervicomedullary junction. INTERVENTION The patient underwent a left, far lateral craniotomy with C1 laminectomy to approach the cervicomedullary junction. The mass was cyst-like and contained scattered crystals and amorphous material consistent with pseudogout. There were no cells with an elevated Ki-67 index. The patient's symptoms and exam improved at follow-up two months later. However, seven months after surgery, she declined once again and was found to have a recurrence. CONCLUSION: A subtotal resection of pseudogout may lead to recurrence. The recurrence can occur in a rapid fashion. Serial MRIs are indicated following resection. Occipitocervical fusion could reduce the likelihood of recurrence in such cases.