Comparison of three imaging techniques in diagnosis of chondrocalcinosis of the knees in calcium pyrophosphate deposition disease.

OBJECTIVE To study the role of different imaging modalities, ultrasonography, conventional radiography (CR) and CT, in visualization of chondrocalcinosis of the knees in patients with CPDD. METHODS Twenty-five patients (14 males and 11 females) with CPDD were enrolled in the study. Diagnosis was made according to D.J. McCarty classification criteria. All patients had arthritis of the knee and underwent aspiration of SF from the knee and microscopic investigation of SF samples. Diagnosis of CPDD was crystal proven. Three imaging methods were performed in patients: CR, CT and US of the knees. RESULTS CR of the knee confirmed cartilage calcification (CC) in 13 patients, CT in 18 patients and US in 25 patients. No difference in age or disease duration between patients with CC detected by different imaging methods was found. CONCLUSION US appeared to be a helpful tool, possibly better than CR or CT, in revealing CC in patients with CPDD. Informativity of CT and CR in the detection of CC is almost equal.