Imaging of chondrocalcinosis: calcium pyrophosphate dihydrate (CPPD) crystal deposition disease -- imaging of common sites of involvement

Calcium pyrophosphate dihydrate (CPPD) crystal deposition disease is characterised by the accumulation of pyrophosphate dihydrate crystals in articular and periarticular tissues and it can be classified as sporadic, hereditary or secondary. The diagnosis frequently rests on radiographic findings. Computed tomography scanning can detect well mineralised deposits in joints and also ultrasound may be useful in detecting CPPD crystal deposits. About MRI recent studies have demonstrated the utility of high field in depiction of CPPD crystal deposits. The aim of this review is to focus on the clinical-classificative and radiological aspects of CPPD, particularly the contribution of the different imaging techniques.