Pomeraniec I Jonathan, Bond Aaron E, Lopes M Beatriz, Jane John A
Departments of Neurosurgery and.
Pathology (Neuropathology), University of Virginia Health Science Center, Charlottesville, Virginia.
J Neurosurg. 2016 Feb;124(2):382-8. doi: 10.3171/2015.2.JNS142318. Epub 2015 Sep 4.
Normal pressure hydrocephalus (NPH) remains most often a clinical diagnosis and has been widely considered responsive to the placement of a cerebrospinal fluid (CSF) shunt. The high incidence of patients with Alzheimer's disease (AD) with NPH symptoms leads to poorer outcomes than would be expected in patients with NPH alone. This article reviews a series of patients operated on for presumed NPH in whom preoperative high-volume lumbar puncture (HVLP) and intraoperative cortical brain biopsies were performed. The data derived from these procedures were then used to understand the incidence of AD in patients presenting with NPH symptoms and to analyze the efficacy of HVLP in patients with NPH and patients with concurrent AD (NPH+AD). A review of the outcomes of shunt surgery is provided.
The cases of all patients who underwent placement of a CSF shunt for NPH from 1998 to 2013 at the University of Virginia by the senior author were retrospectively reviewed. Patients who underwent HVLP and patients who underwent cortical brain biopsies were stratified based on the biopsy results into an NPH-only group and an NPH+AD group. The HVLP results and outcomes were then compared in these 2 groups.
From 1998 to 2013, 142 patients underwent shunt operations because of a preoperative clinical diagnosis of NPH. Of the patients with a shunt who had a diagnosis of NPH, 105 (74%) received HVLPs. Of 142 shunt-treated patients with NPH, 27 (19%) were determined to have concomitant Alzheimer's pathology based on histopathological findings at the time of shunting. Patients who underwent repeat biopsies had an initial positive outcome. After they clinically deteriorated, they underwent repeat biopsies during shunt interrogation, and 13% of the repeat biopsies demonstrated Alzheimer's pathology. Improvements in gait and cognition did not reach significance between the NPH and NPH+AD groups. In total, 105 patients underwent HVLP before shunt placement. In the NPH cohort, 44.6% of patients experienced improvement in symptoms with HVLP and went on to experience resolution or improvement. In the NPH+AD cohort, this proportion was lower (18.2%), and the majority of patients who experienced symptomatic relief with HVLP actually went on to experience either no change or worsening of symptoms (p = 0.0136).
A high prevalence of AD histopathological findings (19%) occurred in patients treated with shunts for NPH based on cortical brain biopsies performed during placement of CSF shunts. HVLP results alone were not predictive of clinical outcome. However, cortical brain biopsy results and the presence of Alzheimer's pathology had a strong correlation with success after CSF shunting. Thirteen percent of patients who initially had a normal cortical brain biopsy result had evidence of AD pathology on repeat biopsy, demonstrating the progressive nature of the disease.
正常压力脑积水（NPH）通常仍是一种临床诊断，并且被广泛认为对脑脊液（CSF）分流术有效。患有阿尔茨海默病（AD）且有NPH症状的患者发病率较高，其预后比单纯NPH患者预期的更差。本文回顾了一系列因疑似NPH接受手术的患者，这些患者术前进行了大容量腰椎穿刺（HVLP）并在术中进行了皮质脑活检。然后利用这些检查所得数据来了解出现NPH症状患者中AD的发病率，并分析HVLP对NPH患者及合并AD（NPH+AD）患者的疗效。还提供了分流手术结果的综述。
回顾性分析1998年至2013年由资深作者在弗吉尼亚大学为NPH进行CSF分流术的所有患者的病例。接受HVLP的患者和接受皮质脑活检的患者根据活检结果被分层为单纯NPH组和NPH+AD组。然后比较这两组的HVLP结果和预后。
1998年至2013年，142例患者因术前临床诊断为NPH而接受了分流手术。在诊断为NPH的分流患者中，105例（74%）接受了HVLP。在142例接受分流治疗的NPH患者中，根据分流时的组织病理学发现，27例（19%）被确定伴有阿尔茨海默病病理改变。接受重复活检的患者最初有阳性结果。在临床病情恶化后，他们在分流检查期间接受了重复活检，13%的重复活检显示有阿尔茨海默病病理改变。NPH组和NPH+AD组在步态和认知方面的改善无显著差异。共有105例患者在分流前接受了HVLP。在NPH队列中，44.6%的患者通过HVLP症状得到改善，并进而症状缓解或改善。在NPH+AD队列中，这一比例较低（18.2%），并且大多数通过HVLP症状缓解的患者实际上随后症状无变化或恶化（p=0.0136）。
根据CSF分流术放置期间进行的皮质脑活检，在接受分流治疗的NPH患者中，AD组织病理学发现的患病率较高（19%）。仅HVLP结果不能预测临床结局。然而，皮质脑活检结果和阿尔茨海默病病理改变与CSF分流术后的成功密切相关。13%最初皮质脑活检结果正常的患者在重复活检时有AD病理改变的证据，表明该疾病具有进展性。
