ROC曲线评价盆腔超声对女童性早熟的诊断价值

The diagnostic values of pelvic ultrasonography in female precocious puberty evaluated by ROC curve

目的采用ROC曲线确定女童不同类型性早熟敏感性及特异性较高的超声参数,得出方便于临床诊断性早熟各超声参数的切割值。方法采用盆腔超声常规检查法测量女童内生殖器17项超声参数:子宫体长,厚,宽,容积,内膜回声;子宫颈长,厚,宫体厚度/宫颈厚度比值(FCR),阴道前后壁厚度;卵巢长,厚,容积,卵泡内径,卵泡数目;子宫动脉收缩期流速,舒张期末流速,阻力指数(RI)。将454例性早熟患儿分为中枢性性早熟(CPP)组,外周性性早熟(PPP)组及乳房早发育(PT)组,将3组454例性早熟患儿组与171例正常同龄女童组盆腔超声多参数测量数据进行比较,观察性早熟患儿组与正常组儿童各项超声参数的差异与特征。结果性早熟患儿平均子宫体长2.2cm,厚1.0cm,容积2.0ml,宫颈厚0.9cm,FCR1.2,阴道壁厚0.4cm,卵巢容积1.2ml,子宫动脉舒张期末流速1.8cm/s,RI为0.90。ROC曲线显示患儿CPP组卵巢的超声参数敏感性及特异性较高,卵巢长度、厚度及卵巢容积的曲线下面积分别达0.92,0.96及0.98;其次为FCR,曲线下面积达0.89,与PPP组及PT组的相应参数相区别。PPP组子宫、宫颈、阴道的超声参数及子宫动脉舒张期末流速、RI均具有较高的特异性及敏感性,宫颈及阴道壁厚度曲线下面积高达0.98,与CPP组及PT组的相应参数相区别。双侧卵巢增大是诊断CPP的可靠依据,早期可无子宫增大。子宫增大,宫颈及阴道壁增厚,子宫内膜显现,若不伴卵巢增大,多考虑PPP。PT患儿子宫、卵巢多无明显形态改变,若有卵巢增大,应警惕发展为CPP,需追踪复查。结论 ROC曲线可在女童盆腔众多超声参数中确定敏感性及特异性较高的超声参数,对女童性早熟早期诊断有重要临床价值。其中早期诊断及鉴别诊断敏感指标是:卵巢容积,宫颈厚度,阴道壁厚度,子宫动脉舒张期末流速。

Objective The comparisons were done among the three groups of female precocious puberty and the variations within high sensitivity and specificity were determined by ROC curve. The cut-off points of pelvic ultrasonographic parameters were achieved for diagnosis of precocious puberty as well. Methods A total of 17 sonogrphic parameters of the internal genitalia in girls by common pelvic uhrasono graphy were measured： uterine length, thickness, width and volume, endometrial echo, cervical length and thickness, ratio of fundal and cervical anteroposterior diameter（FCR）, thickness of vaginal wall, ovarian length, thickness and volume, diameter and number of follicle, peak flow velocity, end diastolic velocity, resistant index（RI） of uterine artery. Four hundred and fifty-four cases of precocious puberty were classified into three groups ： （ 1 ） Central precocious puberty （CPP） ; （ 2 ） Pseudo precocious puberty （PPP） ; （ 3 ） Prema- ture thelarehe （PT）. The multiple sonographic parameters in three groups（454 eases）with female precocious puberty were measured and compared between precocious puberty groups and the 171 healthy age-matched girls. The characteristics and difference of pelvic sonographie parameters in precocious puberty and the healthy girls were observed. Results The sonographic parameters of the female precocious puberty were shown as follows ： the length of uterine body was 2.2 cm, the thickness was 1.0 cm, the volume was 2.0 ml, the thickness of cervix was 0.9 cm, FCR 1.2, the vaginal thickness was 0.4 cm, the volume of ovary was 1.2 ml, the end diastolic velocity of uterine artery was 1.8 cm/s, RI was 0.9. The analysis of ROC curve was done： the ovaries parameters in CPP group were high sensitive with specificity. Compared with PPP and PT group, the ROC area of the ovarian length, thickness and volume in CPP were up to 0.92,0.96 and 0.98 respectively. FCR following the ovaries parameters of the ROC area was about 0. 89. In PPP group, the variations of uterus, cervix, vagina parameters and the end diastolic velocity, RI of uterine arteries were high sensitive with specificity. Compared with the CPP and PT group, the ROC area of cervical and vaginal thickness in PPP were both up to 0.98. The enlargement of ovaries were reliable evidence for diagnosis of CPP. The uterus was normal in early period of CPP. The enlargement of uterus, cervix, vagina and presence of endometrial echo were evidence for diagnosis of PPP, but ovaries. In PT group, the internal genitalia changed without significance. The follow-up sonographic examination should be applied for evaluating enlargement of ovaries to indentify progress of CPP. Conclusions The multiple parameters of pelvic ultrasonography in girls were comparable and the variations with high sensitivity and specificity were determined by ROC curve. The early diagnosis of female precocious puberty had important clinical value. The sensitive parameters for early diagnosis and differentiating precocious puberty are ovarian volume, thickness of cervix and vagina, the end diastolic velocity of uterine arteries.