[Magnetic resonance in the study of patients of short stature of the hypothalamo-hypophyseal origin. Report on 29 cases]

Although growth hormone (GH) deficiency is a very common cause of short stature, many cases are still diagnosed as idiopathic. Magnetic Resonance Imaging (MRI), more clearly than CT, reveals the anatomy of the hypothalamic-hypophyseal region and of the possible alterations (pituitary hypoplasia, interruption of the stalk) causing hormonal deficit. Twenty-nine patients with short stature underwent MRI examinations of the hypothalamic-pituitary region to assess the significance of the correlation between hormonal test and MR patterns. Five patients had normal variants of short stature (NVSS), 7 had multiple pituitary hormone defects (MPHD) and 17 had isolated growth hormone deficiency (IGHD). In patients with MPHD or with severe isolated growth hormone deficit MRI shows interruption of the pituitary stalk with ectopy of the neurohypophysis or a mass. In patients with less severe IGHD and in NVSS, MRI demonstrates a normal pituitary region or a slightly hypoplastic gland, the neurohypophysis being normally situated. MRI may provide an ethiological classification in short stature patients. Typical MR patterns can be demonstrated in cases of dwarfism secondary to a mass in the hypothalamic-pituitary region or to morphological changes of the pituitary stalk, while in transient GH deficit no anatomical abnormalities are observed.