).Calcium pyrophosphate dihydrate deposition disease (CPDD) is a rare crystal arthropathy characterized by the deposition of calcium pyrophosphate crystals in joint spaces, episodes of synovitis, and radiological features of chondrocalcinosis. 1,2 While the disease is most prevalent in the shoulders, pelvis, knees, and joints of the hands, the axial skeleton can be affected, but rarely involves the skull base. 2-4 When involved, CPDD can cause symptoms mimicking more common neurological and neurosurgical pathologies. 2,5 We present a patient who was recently treated at our institution whose pathology demonstrated CPDD.
Case ReportThe patient is a 51-year-old right-handed Caucasian woman with a 12-month history of left ear pain that originated from the temporomandibular joint (TMJ), with some associated swelling, pain with chewing, and mild hearing loss. Her physical examination revealed mild hearing loss on the left side. Computed tomography (CT) and magnetic resonance imaging of the temporal fossa revealed a large mass emanating from the temporal bone at the TMJ (►Fig. 1A, 1B), extending into the greater wing of the sphenoid, and involving the mastoid bone and air cells posteriorly. There was erosion of the petrous carotid canal. A CT-guided biopsy was performed which diagnosed the mass as tophaceous pseudogout (tumoral CPDD).
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