Fig. 14

Sagittal views of magnetic resonance imaging of the cervical cord in four infants with achondroplasia. a There is obliteration of the posterior subarachnoid fluid layer; b In addition to obliteration of the fluid layer posteriorly, there is “nicking” of the posterior cord; c Narrowing of the cord is evident secondary to “waisting” – that is, there is some indentation anteriorly, as well; d An obvious T2 signal abnormality is present