垂体形态正常的特发性生长激素缺乏症在MR动态增强扫描中的特征

Assessment of idiopathic growth hormone deficiency in the morphologically normal pituitary using dynamic contrast-enhanced MR imaging

目的评估MR动态增强扫描在垂体形态正常的特发性生长激素缺乏症(IGHD)中的应用价值。材料与方法选择21例垂体形态正常的IGHD患者及17名正常人,两组均接受垂体冠状面多层面MR动态增强扫描。测量垂体前叶信号强度-时间(SI-T)曲线,记录强化峰值时间(TTP)及最大强化率(Rmax),使用独立样本t检验对比分析两组TTP及Rmax的差异性。对IGHD组TTP、Rmax与生长激素水平进行皮尔森相关系数分析。结果 IGHD患者TTP比正常对照组延长(P<0.05),两组间Rmax差异无统计学意义(P>0.05)。生长激素水平与TTP存在负相关(P<0.05),与Rmax无明显相关性(P>0.05)。结论 MR动态增强扫描中TTP的延长对有临床症状且垂体形态正常的IGHD患者有提示及辅助诊断作用。生长激素水平的缺乏与垂体前叶局部灌注延迟存在关联性。

Objectives： To investigate the dynamic contrast-enhanced MR imaging features of pituitary in the idiopathic growth hormone deficiency（IGHD） patients with morphologically normal pituitary gland.Materials and Methods： 21 IGHD patients with normal pituitary morphology and 17 healthy age-matched controls were included for analysis.Multisection coronal dynamic contrast-enhanced MR imaging of pituitary was performed.Time to peek（TTP） and maximum enhancement ratio（Rmax） were derived from the signal intensity-time curve of anterior pituitary and compared between IGHD patients and normal controls using the independent t test.Pearson correlation analysis was used to determine the correlation between the TTP or Rmax and the growth hormone deficiency levels.Results： The IGHD patients had a prolonged TTP than normal controls（P0.05）,but the Rmax was not significantly different from that in normal controls（P0.05）.The levels of serum growth hormone were negatively correlated with the TTP（P0.05）,but not with Rmax（P0.05）.Conclusions： A delayed TTP on dynamic contrast-enhanced MR imaging could be indicative of IGHD in symptomatic patients with a morphologically normal pituitary.The degree of growth hormone deficiency was associated with regional perfusion delay.