Normal-pressure hydrocephalus: A critical review.

Normal-pressure hydrocephalus (NPH) is a potentially reversible syndrome characterized by enlarged cerebral ventricles (ventriculomegaly), cognitive impairment, gait apraxia and urinary incontinence. A critical review of the concept, pathophysiology, diagnosis, and treatment of both idiopathic and secondary NPH was conducted. We searched Medline and PubMed databases from January 2012 to December 2018 using the keywords "normal-pressure hydrocephalus" / "idiopathic normal-pressure hydrocephalus" / "secondary normal-pressure hydrocephalus" / "NPH" / "ventriculoperitoneal shunt". The initial search produced 341 hits. After careful selection, a total of 54 articles were chosen and additional relevant studies were included during the process of writing this article. NPH is an important cause of potentially reversible dementia, frequent falls and recurrent urinary infections in the elderly. The clinical and imaging features of NPH may be incomplete or nonspecific, posing a diagnostic challenge for medical doctors and often requiring expert assessment to minimize unsuccessful surgical treatments. Recent advances resulting from the use of non-invasive MRI methods for quantifying cerebral blood flow, in particular arterial spin-labeling (ASL), and the frequent association of NPH and obstructive sleep apnea (OSA), offer new avenues to understand and treat NPH.

A hidrocefalia de pressão normal (HPN) é uma síndrome potencialmente reversível marcada por ventrículos cerebrais alargados (ventriculomegalia), declínio cognitivo, apraxia da marcha e incontinência urinária. Revisar criticamente o conceito, a fisiopatologia, o diagnóstico e o tratamento da HPN idiopática e secundária. Os autores acessaram as bases de dados Medline e Pubmed entre janeiro de 2012 e dezembro de 2018, utilizando as palavras-chave "normal-pressure hydrocephalus" / "idiopathic normal-pressure hydrocephalus" / "secondary normal-pressure hydrocephalus" / "NPH" / "ventriculoperitoneal shunt". A busca inicial resultou em 341 artigos. Após cuidadosa seleção, 54 estudos foram escolhidos e pesquisas adicionais foram incluídas durante o processo de elaboração do manuscrito. A HPN é uma importante causa de demência potencialmente reversível, quedas frequentes e infecção urinária recorrente em idosos. As características clínicas e de imagem da HPN podem ser incompletas ou inespecíficas, de modo que este se torna um diagnóstico difícil para médicos. Não raro uma avaliação por especialista é necessária, visando minimizar tratamentos cirúrgicos ineficazes. Avanços recentes advindos do uso não invasivo de ressonância magnética para quantificação do fluxo sanguíneo cerebral, em particular arterial spin-labeling (ASL), assim como a usual associação entre HPN e apneia obstrutiva do sono representam novos meios de entender e de tratar a HPN.

Normal-pressure hydrocephalus: A critical review / Hidrocefalia de pressão normal: uma revisão crítica

ABSTRACT. Normal-pressure hydrocephalus (NPH) is a potentially reversible syndrome characterized by enlarged cerebral ventricles (ventriculomegaly), cognitive impairment, gait apraxia and urinary incontinence. A critical review of the concept, pathophysiology, diagnosis, and treatment of both idiopathic and secondary NPH was conducted. We searched Medline and PubMed databases from January 2012 to December 2018 using the keywords "normal-pressure hydrocephalus" / "idiopathic normal-pressure hydrocephalus" / "secondary normal-pressure hydrocephalus" / "NPH" / "ventriculoperitoneal shunt". The initial search produced 341 hits. After careful selection, a total of 54 articles were chosen and additional relevant studies were included during the process of writing this article. NPH is an important cause of potentially reversible dementia, frequent falls and recurrent urinary infections in the elderly. The clinical and imaging features of NPH may be incomplete or nonspecific, posing a diagnostic challenge for medical doctors and often requiring expert assessment to minimize unsuccessful surgical treatments. Recent advances resulting from the use of non-invasive MRI methods for quantifying cerebral blood flow, in particular arterial spin-labeling (ASL), and the frequent association of NPH and obstructive sleep apnea (OSA), offer new avenues to understand and treat NPH.

RESUMO. A hidrocefalia de pressão normal (HPN) é uma síndrome potencialmente reversível marcada por ventrículos cerebrais alargados (ventriculomegalia), declínio cognitivo, apraxia da marcha e incontinência urinária. Revisar criticamente o conceito, a fisiopatologia, o diagnóstico e o tratamento da HPN idiopática e secundária. Os autores acessaram as bases de dados Medline e Pubmed entre janeiro de 2012 e dezembro de 2018, utilizando as palavras-chave "normal-pressure hydrocephalus" / "idiopathic normal-pressure hydrocephalus" / "secondary normal-pressure hydrocephalus" / "NPH" / "ventriculoperitoneal shunt". A busca inicial resultou em 341 artigos. Após cuidadosa seleção, 54 estudos foram escolhidos e pesquisas adicionais foram incluídas durante o processo de elaboração do manuscrito. A HPN é uma importante causa de demência potencialmente reversível, quedas frequentes e infecção urinária recorrente em idosos. As características clínicas e de imagem da HPN podem ser incompletas ou inespecíficas, de modo que este se torna um diagnóstico difícil para médicos. Não raro uma avaliação por especialista é necessária, visando minimizar tratamentos cirúrgicos ineficazes. Avanços recentes advindos do uso não invasivo de ressonância magnética para quantificação do fluxo sanguíneo cerebral, em particular arterial spin-labeling (ASL), assim como a usual associação entre HPN e apneia obstrutiva do sono representam novos meios de entender e de tratar a HPN.

Effect of spinal tap test on the performance of sit-to-stand, walking, and turning in patients with idiopathic normal pressure hydrocephalus.

The aim of the study was to investigate the effect of the spinal tap test on sit-to-stand (STS), walking, and turning and to determine the relationship among the outcome measures of STS, walking, and turning in patients with iNPH. Twenty-seven patients with clinical symptoms of iNPH were objectively examined for STS, walking, and turning by the Force Distribution Measurement (FDM) platform connected with a video camera. Assessments were performed at before and 24 hours after spinal tap. Motor abilities were assessed by the STS time, time of walking over 3 meters, and time and number of steps when turning over 180 degrees. Significant improvements were found in the STS time (p = 0.046), walking time (p = 0.048), and turning step (p = 0.001). In addition, turning time was improved but not statistically significant (p = 0.064). Significant relationships were found among all outcome measures (p < 0.001). The relationship among these outcome measures indicated that the individuals had similar ability levels to perform different activities. This may serve as a new choice of outcome measures to evaluate the effect of intervention in different severity levels of patients with iNPH.

Cognitive impairment predicts worse short-term response to spinal tap test in normal pressure hydrocephalus.

INTRODUCTION: In patients with idiopathic normal pressure hydrocephalus (iNPH), the spinal tap test (STT) is commonly used to predict ventriculoperitoneal shunt responsiveness. Clinical improvement following STT usually is measured by testing gait function. In our study, we investigated the impact of cognitive impairment on gait improvement after STT. METHODS: 22 patients with the clinical and radiological diagnosis of iNPH underwent gait analyses (mobile measuring system Medilogic) before and 2-4h after STT in self-paced gait velocity over 7m. Prior to STT, cognition was evaluated by the Mini Mental State Examination (MMSE). MMSE<24/30 points was used to define the subgroup of patients with cognitive impairment (iNPH-CI). Spatio-temporal parameters of gait before STT vs. after STT were analyzed with ANOVA with repeated measures. RESULTS: 1. Baseline gait parameters did not differ between the two groups: patients with iNPH and normal cognition (n=11) and patients with iNPH-CI (n=11). 2. Following STT, there was significant improvement of gait parameters in patients without cognitive impairment, while patients with iNPH-CI did not benefit from STT. CONCLUSION: Subjects with iNPH have a higher probability of lack of gait improvement 2-4h following STT, if cognitive impairment is present. Further studies are needed to elucidate the associations of cognitive impairment and quantitative gait parameters measured early and at later time points after STT.

Measuring changes in the optic nerve sheath diameter in patients with idiopathic normal-pressure hydrocephalus: a useful diagnostic supplement to spinal tap tests.

BACKGROUND AND PURPOSE: Cerebrospinal fluid (CSF) removal improves clinical symptoms of many patients with idiopathic normal-pressure hydrocephalus (iNPH). The aim of this study was to investigate the correlation of changes in the optic nerve sheath diameter (ONSD) with patient responses to CSF removal. METHODS: Transorbital ultrasonography was performed to obtain ONSD measurements in 31 patients with iNPH before and after lumbar puncture. Measurements were obtained while patients were supine and upright. Changes in the ONSD between supine and upright positions [ONSD variability (ONSD-V)] were assessed and compared with those in 60 healthy volunteers. ONSD-V was correlated with relative changes in a validated iNPH severity (Boon) score. RESULTS: Mean pre-puncture ONSD-V was significantly lower in healthy volunteers and patients with no response to CSF removal (Fisher test) [0.05 ± 0.14 mm (SD)] than in responsive patients [0.37 ± 0.20 mm (SD), P < 0.001]. ONSD-V predicted response to the spinal tap test (odds ratio, 0.30; 95% confidence interval, 0.12-0.75 mm, P = 0.011). The higher the ONSD-V, the better the therapeutic effect (χ2 = 14.980, P < 0.001). The post-spinal tap test ONSD-V correlated significantly with clinical severity in the motor portion of the Boon score [0.16 ± 0.23 mm (SD), P = 0.003]. CONCLUSIONS: The ONSD-V before and after spinal tap test correlated well with the clinical effects of CSF removal. Transorbital ultrasonography seems to be a reliable, safe add-on to the Fisher test and may support selection of patients for shunt intervention.

The Effect of Spinal Tap Test on Different Sensory Modalities of Postural Stability in Idiopathic Normal Pressure Hydrocephalus.

BACKGROUND/AIMS: Postural instability in patients with normal pressure hydrocephalus (NPH) is a most crucial symptom leading to falls with secondary complications. The aim of the current study was to evaluate the therapeutic effect of spinal tap on postural stability in these patients. METHODS: Seventeen patients with clinical symptoms of NPH were examined using gait scale, computerized dynamic posturography (CDP), and neuropsychological assessment. Examinations were done before and after spinal tap test. RESULTS: The gait score showed a significant improvement 24 h after spinal tap test in all subtests and in the sum score (p < 0.003), while neuropsychological assessment did not reveal significant differences 72 h after spinal tap test. CDP showed significant improvements after spinal tap test in the Sensory Organization Tests 2 (p = 0.017), 4 (p = 0.001), and 5 (p = 0.009) and the composite score (p = 0.01). Patients showed best performance in somatosensory and worst performance in vestibular dominated tests. Vestibular dominated tests did not improve significantly after spinal tap test, while somatosensory and visual dominated tests did. CONCLUSION: Postural stability in NPH is predominantly affected by deficient vestibular functions, which did not improve after spinal tap test. Conditions which improved best were mainly independent from visual control and are based on proprioceptive functions.