Imaging Findings in Calcium Pyrophosphate Dihydrate Crystal Deposition Disease

Presentation Format: Educational poster presentation.

Purpose or Learning Objective: (1) To understand the diagnostic patterns for the radiographic diagnosis of calcium pyrophosphate crystal deposition disease (CPPD); (2) to become familiar with other conventional imaging techniques used to diagnose CPPD crystal deposition disease, and (3) to demonstrate the appearance of this disorder using ultrasonography (US), computed tomography, and dual-energy computed tomography (DECT).

Methods or Background: CPPD has various clinical patterns that may resemble other arthritides. Its appearance using conventional radiographs can resemble other degenerative joint diseases with only very subtle but important differences. For example, in the wrist, degenerative diseases affect predominantly the first carpometacarpal and trapezioscaphoid areas, but in CPPD the radiocarpal compartment is the most common site of abnormality. CPPD causes rapidly progressing osteoarthritis that can trigger severely painful attacks. CPPD is also associated with certain diseases, for example hyperparathyroidism and hemochromatosis. These diseases demonstrate very similar radiologic findings as CPPD but are treated very differently.

Results or Findings: The differential diagnosis of CPPD on radiographs usually includes intra-articular calcification, periarticular calcification, and pyrophosphate arthropathy. The gold standard of diagnosing CPPD remains the aspiration of crystals, identifying calcium pyrophosphate crystals under polarized light microscopy. In conventional radiography, chondrocalcinosis is the main diagnostic criteria in the clinic. However, this finding may not appear in every radiograph, and the presence of chondrocalcinosis does not indicate a definitive diagnosis of CPPD. Thus new research is being conducted using other imaging modalities to diagnose CPPD. US imaging has been found to have a high sensitivity and specificity in identifying CPPD. Another new technique called a DECT scan, used in experiments, is also able to identify calcium pyrophosphate crystals. However, this technique is not yet used in the clinical setting.

Conclusion: We have demonstrated conventional and new imaging techniques associated with CPPD.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
03 June 2021