Persistent High MR Signal of the Po

showed a normal posterior pituitary signal on T1-weightedhealthy control subjects and in patients with primary polyuria or nephrogenic diabetes insip-idus (3, 8, 9). The absence of a posterior pitu-itary hyperintensity in a patient with central di-abetes insipidus can be the only and earliest images, normal morphology of the anterior gland, and a thin stalk. Repeat MR imaging at the ages of 8, 9, and 11 years revealed unchanged anterior pituitary gland and stalk morphology with a persistence of the posterior pituitary signal (Fig 1). DNA analysis performed accordin