Background After ventriculoperitoneal shunt surgery for idiopathic normal pressure hydrocephalus (iNPH) with adjustable gravitational valves, a certain proportion of patients develop secondary clinical worsening after initial improvement of clinical symptoms. The aim of this study was to analyze this group of patients with secondary deterioration and to evaluate the performed shunt management. Methods For this investigation, we retrospectively reviewed our NPH registry for patients included between 1999 and 2013 with a decrease by a minimum of two points in the Kiefer score in the first year of follow up and an increase of two points in the Kiefer score between the second and the fifth year after shunt surgery (secondary deterioration). Then, we analyzed the patient’s shunt management (adapting the valve pressure setting, shuntography, valve replacement, catheter replacement, implant an adjustable gravitational unit). Additionally, we searched for risk factors for secondary deterioration. Results Out of 259 iNPH patients, 53 (20%) patients showed secondary deterioration on an average of 2.7 (2–4 years) years after shunt surgery. Fourteen (26%) patients with secondary deterioration improved after shunt or valve management and 58% remained without clinical benefit after management. We had a drop-out rate of 15% due to incomplete datasets. Our shunt management reduced the rate of secondary deterioration from 20 to 15%. On the basis of our findings, we developed an algorithm for shunt management. Risk factors for secondary deterioration are the age of the patient at the time of shunting, newly diagnosed neurodegenerative diseases, and overdrainage requiring adjusting the valve to higher-pressure levels. Conclusion Twenty percent of patients with iNPH were at risk for secondary clinical worsening about 3 years after shunt surgery. About one-fourth of these patients benefited for additional years from pressure level management and/or shunt valve revision. Our findings underline the need for long-term follow-ups and intensive shunt management to achieve a favorable long-term outcome for patients with iNPH and VPS.

中文翻译：

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脑室腹腔分流术后正常压力脑积水患者继发性恶化：建议的治疗算法

背景 特发性正常压力脑积水（iNPH）可调节重力瓣脑室腹腔分流手术后，一定比例的患者在临床症状初步改善后出现继发性临床恶化。本研究的目的是分析这组继发性恶化的患者并评估所进行的分流管理。方法 在本次调查中，我们对 1999 年至 2013 年间纳入的患者的 NPH 登记进行了回顾性审查，在随访的第一年中 Kiefer 评分至少降低了 2 分，并且在随访期间 Kiefer 评分增加了 2 分。分流手术后第二年和第五年（继发性恶化）。然后，我们分析了患者的分流管理（调整瓣膜压力设置、分流造影、瓣膜更换、导管更换、植入可调节重力单元）。此外，我们还搜索了继发性恶化的风险因素。结果 在 259 名 iNPH 患者中，53 名 (20%) 患者在分流手术后平均 2.7（2-4 年）内出现继发性恶化。14 名 (26%) 继发性恶化的患者在分流或瓣膜管理后有所改善，58% 的患者在管理后仍没有临床获益。由于数据集不完整，我们的辍学率为 15%。我们的分流管理将二次恶化率从 20% 降低到 15%。根据我们的发现，我们开发了一种分流管理算法。继发性恶化的危险因素是分流时患者的年龄、新诊断的神经退行性疾病、以及需要将阀门调整到更高压力水平的过度排水。结论 20% 的 iNPH 患者在分流手术后约 3 年有继发性临床恶化的风险。这些患者中约有四分之一从压力水平管理和/或分流阀修正中获益多年。我们的研究结果强调需要长期随访和强化分流管理，以实现 iNPH 和 VPS 患者的良好长期结果。