脑脊液引流试验对原发性正常压力性脑积水分流手术效果的预测

目的应用脑脊液引流试验(Tap试验)对原发性正常压力性脑积水(iNPH)病人进行术前评估,预测分流手术的有效性。方法前瞻性研究50例iNPH病人,先行Tap试验,5 d后行脑室-腹腔分流术(V-P分流术)。Tap试验前1 h、Tap试验后24 h及分流术后7 d分别对病人的神经功能进行评估。通过筛检试验统计分析评估Tap试验并预测iNPH病人分流手术的有效性。结果 Tap试验阳性31例,其中V-P分流术临床症状改善30例,未改善1例;Tap试验阴性19例,其中V-P分流术后症状改善6例,未改善13例。结果提示Tap试验对iNPH分流手术的灵敏度为83.3%,特异度92.9%,阳性预测率96.8%,阴性预测率68.4%。结论 Tap试验是理想的iNPH分流手术疗效的阳性预测指标。

Forecast of shunting effect of cerebrospinal fluid tap test for idiopathic normal pressure hydrocephalus

Objective To make preoperative evaluation for patients with idiopathic normal pressure hydrocephalus （iNPH） by cerebrospinal fluid tap test （Tap test） forecasting the validity of shunting. Methods Clinical data of 50 iNPH patients were analyzed prospectively. All patients underwent the Tap test and then ventriculo-peritoneal （V-P） shunt five days later. Nervous function was evaluated 1 h before the Tap test, 24 h after the Tap testand 7 days after shunting respectively. The prognostic value of Tap test in shunting for patients with iNPH was analyzed by screening test method. Results The Tap test was positive in 31 patients, including 30 improved after shunting and 1 unchanged. While the Tap test was negative in 19 patients, including 6 improved after shunting and 13 unchanged. Thus, the sensitivity, specificity, positive predictive value and negative predictive value of the Tap test were respectively 83.3%, 92.9%, 96.8% and 68.4%. Conclusion The Tap test is an ideal positive predictor for therapeutic effect of shunting in patients with iNPH.