Pituitary gland imaging and outcome

Magnetic resonance imaging (MRI) allows a detailed and precise anatomical study of the pituitary gland by differentiating between the anterior and posterior pituitary lobes. The identification of posterior pituitary hyperintensity, now considered a marker of neurohypophyseal functional integrity, has been the most striking advance for the diagnosis and understanding of anterior and posterior pituitary diseases. The advent of MRI has in fact led to a significant improvement in the understanding of the pathogenesis of disorders that affect the hypothalamo-pituitary area. Today, there is convincing evidence to support the hypothesis that marked MRI differences in pituitary morphology indicate a diverse range of disorders which affect the organogenesis and function of the anterior pituitary gland with different prognoses. Furthermore, the association of extrapituitary malformations accurately defined by MRI has supported a better definition of several conditions linked to pituitary hormone deficiencies and midline defects. MRI is a very informative procedure that should be used to support a diagnosis of hypopituitarism. It is useful in clinical management, because it helps endocrinologists determine which patients to target for further molecular studies and genetic counselling, which ones to screen for additional hormone deficits, and which ones may need growth hormone replacement into adult life.