摘要目的 探讨胫骨、桡骨超声波传播速度(SOS)在早期婴儿佝偻病的变化规律及诊断价值.方法 对2004年5月至2007年12月在我院儿童保健门诊就诊,符合1986年卫生部颁布婴幼儿佝偻病诊断标准拟诊为佝偻病的157例婴儿,和同期正常体格检查并随访3个月无佝偻病症状体征的124例健康儿(健康对照组),采用骨密度超声仪检测胫骨和桡骨SOS.结果 临床拟诊佝偻病157例中,127例行腕骨正位X线平片,90例有影像学改变(平片阳性组),37例无影像学改变(平片阴性组).临床拟诊佝偻病组婴儿胫骨和桡骨SOS、Z-Score(Z值)明显低于健康对照组(Mann-Whitney Test胫骨u值分别为-10.411、-10.399,桡骨u值分别为-5.646、-5.517,P=0.000);平片阳性组胫骨SOS、Z值低于平片阴性组,但差异无统计学意义;SOS和Z值与X线平片影像改变呈正相关(胫骨r值分别为0.581、0.677,桡骨r值分别为0.316、0.467,P=0.000);以左腕骨X线平片阳性确诊佝偻病为标准绘制胫骨、桡骨SOS、Z值ROC曲线,胫骨SOS、Z值ROC曲线下面积分别为0.812、0.799(95% CI:0.758～0.856、0.742～0.855,P=0.000);桡骨SOS、Z值ROC曲线下面积分别为0.715、0.697(95% CI:0.650～0.780、0.631～0.764,P=0.000).依据灵敏度和误诊率(1-特异度)对应关系甄选Z值界点,胫骨Z值界点为-2.05～-1.95时,灵敏度为0.8～0.9,特异度为0.733～0.702.桡骨灵敏度在0.7以上时其特异度低于0.524.结论 骨超声波检测可发现婴儿骨矿化不足,佝偻病早期骨骼尚未发现影像改变时,定量SOS值已有明显减低,胫骨SOS可作为预示早期婴儿佝偻病的指标,尚不能判断严重程度.

abstractsObjective To explore rules of changes in velocity of ultrasound wave transmission at the tibia and radius by a quantitative bone mineral density ultrasound scanner in examination of early incipient rickets in infants and its significance in clinical diagnosis.Methods One hundred and fifty-seven infants who visited child health-care clinic of the Capital Institute of Pediatrics,Beijing during May 2004 to December 2007 and clinically diagnosed as rickets according to the Criteria of Diagnosis for Rickets in Infants and Young Children formulated in 1986 by the Ministry of Health,as well as 124 normal healthy infants as controls,were enrolled in the study and followed-up for three months.Velocity of ultrasound wave transmission at the tibia and radius in all the infants were measured by a bone mineral density ultrasound scanner (Sunlight Omnisense 7000R made in Israel).Results One hundred and fifty-seven infants were clinically diagnosed as rickets,127 of them undergone with carpal plane roentgenography and 90 of the 127 with positive change in bone x-ray imaging and 37 without it.Velocity of ultrasound wave transmission at the tibia and radius measured by z-score was significantly lower in infants with clinically diagnosed rickets than that in healthy controls (Z-values of-10.411 and-10.399 at the tibia and-5.646 and-5.517 at the radius,respectively,P = 0.000 with Mann-Whitney test).Velocity of ultrasound wave transmission at the tibia and radius measured by z-score was lower in those with positive change in x-my imaging than that in those without it,but not reaching a level of statistically significant difference.Velocity of ultrasound wave transmission and z-score correlated positively with change in bone x-ray imaging,respectively with Spearman coefficients of correlation of 0.581 and 0.677 for tibia,0.316 and 0.467 for radius (P = 0.000).Receiver operating characteristic (ROC) curve was drawn from those with rickets and positive left carpal plane roetgenograph.Area under curve of ROC for z-score of velocity of ultrasound wave transmission at the tibia was 0.812 and 0.799 (95% CI 0.758-0.856 and 0.742-0.855,P =0.000),respectively.Area under ROC curve of z-score of velocity of ultrasound wave transmission at the radius was 0.715 and 0.697 (95% CI 0.650-0.780,0.631-0.764,P =0.000),respectively.Cut-off value of z-score was-205--1.95 at the tibia,according to the largest sensitivity and the least false-positivity,with sensibility of 0.8 to 0.9 and specificity of 0.733 to 0.702.As its sensitivity at the radius was more than 0.7,its specificity was lower than 0.524.Conclusions Quantitative ultrasound scanning can be used to detect insufficient bone mineral density in infants and their early skeletal change by rickets but without change in bone x-ray imaging.Velocity of ultrasound wave transmission at the tibia can be used as an indicator to predict early rickets in infants rather than its severity.