33 HIPOTHALAHO-PITUITARY AXIS (HPA) BY MAGNETIC RESONANCE IMAGING (RI) IN GROWTH HORMONE DEFICIENCY

Structural abnormalities of the HPA have been detected by MRI in GH deficient patients. We studied 29 children(18 boys and 11 girls) between 5-21 yr of age with GH deficiency: isolated(IGHD) or associated with multiple pituitary deficiencies (MPD). 10 cases refered abnormal deliveries. All children had GH peak levels less than 4.5ng/ml during clonidine and insulin tests, and submitted to combined TRH 200ug, GnRH 100ug and insulin 0.1 U/kg tests. Absence of TSH and PRL increment after test defined the GH deficiency as pituitary, and elevated basal TSH levels and/or high peak TSH and prolonged response defined GH deficiency as hypothalamic. MRI was performed using a 1.5 Tesla (Sigma GE) system, using spin echo sequences. The anomalies observed were:total transection of the stalk (TTS), thin stalk (TS), reduced pituitary parenchyma (RPP) and ectopic neurohypophysis (ENH).