OBJECTIVE: In patients with GH deficiency (GHD), magnetic resonance imaging (MRI) has revealed morphological abnormalities such as pituitary hypoplasia, pituitary stalk agenesis (PSA) and ectopia of the posterior pituitary (PPE). The MRI anomalies have been more frequently reported in patients with multiple pituitary hormone deficiency (MPHD) than in subjects with isolated GH deficiency (IGHD). The aim of this work was to define which MRI anatomical abnormalities of the hypothalamo-pituitary area can be considered as a prognostic marker of permanent GHD. DESIGN: To investigate the relationship between the neuroradiological images and endocrine findings, we clinically re-evaluated 93 out of the 121 GHD patients with IGHD and MPHD previously studied. RESULTS: No additional hormone deficiencies were observed in 55 out of 60 patients initially classified as having IGHD with a normal (15 cases) or reduced (40 cases) pituitary gland size, without other MRI abnormalities. The remaining five children, who had initially shown an apparently IGHD in spite of PSA and PPE, developed a MPHD over time. In 33 MPHD patients with (25 cases) or without (8 cases) MRI abnormalities, the associated hormone deficiencies were confirmed during follow-up. CONCLUSIONS: The IGHD patients showing PSA and PPE inevitably develop additional hormone deficiencies, while IGHD subjects having no MRI abnormalities maintain IGHD. Moreover, the anatomical abnormalities of the hypothalamo-pituitary area can be considered as a prognostic marker of permanent GHD.