Lieb J M, Stippich C, Ahlhelm F J
Abteilung für diagnostische und interventionelle Neuroradiologie, Klinik für Radiologie und Nuklearmedizin, Universitätsspital Basel, Petersgraben 4, 4031, Basel, Schweiz,
Radiologe. 2015 May;55(5):389-96. doi: 10.1007/s00117-014-2797-1.
Normal pressure hydrocephalus (NPH) is a disorder found mainly in the elderly (> 60 years) with an increasing prevalence with age and is one of the few treatable causes of dementia. If untreated NPH often leads to severe motor, psychomotor and irreversible cognitive deficits. The pathogenesis is not yet fully understood. Clinical symptoms consist of the (not always complete) classical triad of equilibrium and gait disturbances followed later by incontinence and dementia. Symptoms often show a gradual progression to irreversibility in non-treated patients; therefore, early diagnosis and treatment are mandatory. Important differential diagnoses are Parkinson's disease (similar gait), Alzheimer's disease and vascular dementia, not least due to the high comorbidity of these conditions with NPH.
The standard radiological method for evaluation of NPH is conventional cross-sectional imaging that typically shows ventriculomegaly (Evans' index > 0.3 and cella media index < 4) often combined with the so-called disproportionately enlarged subarachnoid space hydrocephalus (DESH) pattern (tight convexity sulci and enlarged sylvian fissure). These findings should be differentiated from ventriculomegaly in atrophy combined with enlarged convexity sulci.
Special magnetic resonance imaging (MRI) techniques can be used to evaluate cerebrospinal fluid (CSF) flow but are not yet part of the diagnostic guidelines.
ACHIEVEMENTS/PRACTICAL RECOMMENDATIONS: Combined with cross-sectional imaging, well-established clinical and invasive diagnostic tests, such as repeated spinal tap or lumbar drainage with re-evaluation of clinical symptoms lead to a diagnosis and help with preoperative patient selection for CSF diversion. Ventriculoperitoneal CSF shunting has proven to be safe and is the only known successful therapy for NPH.
正常压力脑积水（NPH）是一种主要见于老年人（>60岁）的疾病，其患病率随年龄增长而增加，是少数可治疗的痴呆病因之一。若不治疗，NPH常导致严重的运动、精神运动及不可逆的认知缺陷。其发病机制尚未完全明确。临床症状包括（并非总是完全具备）经典的三联征，即平衡和步态障碍，随后出现尿失禁和痴呆。在未治疗的患者中，症状通常呈逐渐进展至不可逆；因此，早期诊断和治疗至关重要。重要的鉴别诊断包括帕金森病（步态相似）、阿尔茨海默病和血管性痴呆，尤其是因为这些疾病与NPH的高共病率。
评估NPH的标准放射学方法是传统的横断面成像，通常显示脑室扩大（埃文斯指数>0.3且中脑导水管指数<4），常伴有所谓的蛛网膜下腔不成比例扩大性脑积水（DESH）模式（脑沟紧密凸出且外侧裂增宽）。这些发现应与萎缩合并脑沟增宽的脑室扩大相鉴别。
特殊的磁共振成像（MRI）技术可用于评估脑脊液（CSF）流动，但尚未成为诊断指南的一部分。
成果/实用建议：结合横断面成像、成熟的临床和侵入性诊断测试，如重复腰椎穿刺或腰椎引流并重新评估临床症状，可得出诊断并有助于术前选择脑脊液分流的患者。脑室腹腔脑脊液分流已被证明是安全的，是已知的唯一成功治疗NPH的方法。
