Pituitary height at magnetic resonance imaging in pediatric isolated growth hormone deficiency.

BACKGROUND: Magnetic resonance imaging (MRI) is used for neuroradiologic evaluation of patients with idiopathic growth hormone deficiency (IGHD). OBJECTIVES: To compare pituitary height and morphology at MRI between patients with IGHD and controls. MATERIALS AND METHODS: This retrospective study was conducted in pediatric patients, 3 years-15 years old, who had had brain MRI with non-contrast-enhanced midsagittal T1-weighted images. These images were measured for pituitary height and morphology of the pituitary gland including shape, stalk and posterior pituitary bright spot was evaluated. RESULTS: One hundred and nineteen patients were included, with 49 and 70 patients assigned to the study and control groups, respectively. Mean pituitary height was significantly less in the IGHD group than in the control group (3.81 mm±1.38 vs. 4.92 mm±1.13, retrospectively; P<0.001). Subgroup analysis revealed a significant difference in the pituitary height between groups in the prepubertal (8-10 years) and pubertal (11-13 years) periods (P=0.039 and P=0.006, respectively) and a trend toward significance in the postpubertal period (P=0.053). There was a significant difference in pituitary shape between IGHD and controls when combining grades III, IV and V (P=0.007). Other abnormal MRI findings of the pituitary stalk and posterior bright spot were significantly more often observed in the IGHD group (P<0.05). CONCLUSION: Pituitary height was significantly smaller in patients with IGHD than in controls during prepuberty and puberty. Abnormal concave superior contour, hypoplastic stalk and absent/ectopic posterior bright spot were observed significantly more often among patients with IGHD.