ABSTRACT
The so-called "crowned dens" is a peculiar manifestation of calcium crystal deposition diseases, either caused by calcium pyrophosphate dihydrate or caused by calcium hydroxiapatite crystals, characterized by the presence of calcific deposits around the odontoid, often showing a crown-like configuration on imaging. It has protean clinical and radiological pictures, and care should be taken to avoid misinterpretation and diagnostic errors. Although asymptomatic in many patients, this entity may present as a predominantly algic or febrile condition, and in some cases, signs of compression of the spinal cord may be the major complaint. The detection of calcifications in the periodontoid tissues is the key to the diagnosis, erosive osseous changes, and variably calcified soft-tissue masses being occasionally associated. Computed tomography is the most important imaging study to be performed in this setting.
Subject(s)
Calcinosis/diagnosis , Magnetic Resonance Imaging/methods , Odontoid Process/diagnostic imaging , Odontoid Process/pathology , Spinal Diseases/diagnosis , Tomography, X-Ray Computed/methods , Aged , Aged, 80 and over , Female , Humans , Male , Middle AgedABSTRACT
Biphosphonates are now being used experimentally in children to increase bone mass, but their long-term effects remain an issue of concern. We report two cases of biphosphonate-induced radiographic changes in children with rheumatic diseases. Our experience supports the view that clinical improvement and radiographic findings after biphosphonate therapy are related to increased bone mineral density, without effects on the inflammatory process itself. Biphosphonates seem to act in rheumatic diseases by reducing bone turnover instead of improving disease activity.
