Kniest dysplasia: MR correlation of histologic and radiographic peculiarities.

Unossified epiphyses of Kniest dysplasia patients histologically reveal a bizarre pattern of chondrocytes lying amid a highly vacuolated matrix giving rise to the name "Swiss cheese" cartilage. The ossified epiphyses also are unusual in showing clouds of dense punctate calcifications randomly distributed throughout. Both unossified and ossified epiphyses reveal on MR imaging a similar pattern of lakes of bright T2 signal against a relatively normal background, which represents an interesting analogue to the histologic and radiographic features.