Magnetic resonance images of the hypothalamic-pituitary area in idiopathic growth deficiency.

In order to describe the magnetic resonance imaging (MRI) findings in hypothalamic-pituitary area and its clinical relevance in patients with idiopathic growth hormone deficiency (IGHD), the MR imagings of 26 patients with IGHD were analyzed. On MRI, 24 out of 26 cases (92.3%) showed apparent pituitary upper margin depression; 8 out of 26 cases (30.8%) showed definite pituitary stalk transection; 22 out of 26 cases (84.6%) showed absence of the normal posterior pituitary bright spot. The bright lipidlike signal on T1W1 images at the median eminence distal to the breaking point (so-called ectopic posterior lobe) was found in 4 out of 26 cases (15.4%). According to the MRI findings of the pituitary stalks, the 26 cases were divided into three groups; group A of 8 cases (31%) characterized by the definite transaction of stalk; group B of 13 cases (50%) defined by the possible stalk transection; and group C of 5 cases (19%) with no definite stalk transection. MRI findings were consistent with the clinical and endocrine tests. The stalk transection was statistically significantly difference in insulin test, L-dopa/p test, and height standard deviation score (P < 0.05). The MRI of hypothalamic-pituitary area may differentiate partial IGHD form stalk-transected, doubtful transection and without transection.