Goodbye Diabetes Insipidus

Diabetes insipidus is mainly caused by AVP deficiency. Other causes are resistance to the action of AVP on the kidney or an excess of vasopressinase produced by the placenta. The denomination AVP deficiency is today logically preferred to diabetes insipidus. The role of MRI in the diagnosis is severely discussed in the endocrinological community, arguing that a large percentage of patients with AVP deficiency have a normal posterior pituitary high signal in T1W MRI and conversely that a substantial percentage of normal volunteers have not. In fact, the normal T1W signal of the posterior lobe can be confused with a fatty dorsum sellae or with a mucinous Rathke cleft cyst on a sagittal view. An axial T1W sequence eliminates these causes of error and is reliable for the diagnosis of AVP deficiency of central origin.