腰穿放液试验在正常压力脑积水病人术前评估中的应用及意义

The predictive value of cerebrospinal fluid tap test in the outcome of shunting for normal-pressure hydrocephalus

目的评价腰穿放液试验在正常压力脑积水病人术前评估中的应用价值。方法对2008年6月至2011年3月期间入选的60例正常压力脑积水病人进行前瞻性研究。病人先行腰穿放液试验,5天后行脑室-腹腔分流术。腰穿放液前、放液后24h及分流术后1周分别对病人"三联征"进行定量评估,并通过筛检试验统计方法分析腰穿放液试验预测正常压力脑积水分流手术的有效性。结果腰穿放液试验阳性36例,行分流手术后临床症状改善35例,1例未改善;腰穿放液试验阴性24例,分流术后改善8例,16例未改善。提示分流手术总有效率71.7%;腰穿放液试验对正常压力脑积水分流手术的灵敏度为81.4%,特异度94.1%,阳性预测率97.2%,阴性预测率66.7%。结论正常压力脑积水术前腰穿放液试验阳性者分流手术可望获得良好疗效。

Objective To evaluate the predictive value of cerebrospinal fluid tap test in the outcome of shunting for normal-pressure hydrocephalus（NPH）.Methods 60 NPH patients were included in the prospective study between June of 2008 and March of 2011.All patients underwent the tap test and then V-P shunt surgery five days later.Clinical changes of the classical triad of symptoms were assessed before,24h after the tap test and one week after shunting.The prognostic value of tap test in shunting for NPH was analyzed by the screening test method.Results The tap test was positive in 36 patients among which 35 improved after shunt,and 1 was unchanged;the tap test was negative in 24 patients among which 8 improved after shunt,and 16 were unchanged.Thus the total effective rate of shunting for NPH is 71.7%;Tap test has a 81.4 % sensitivity and a 94.1 % specificity for predicting the shunt effectiveness of NPH.The positive predictive value of a positive tap test was 97.2%,and the predictive value of a negative tap test was 66.7%.Conclusion Cerebrospinal fluid tap test is promising predictor of shunt effectiveness for normal-pressure hydrocephalus.