Nationwide Incidence of Normal Pressure Hydrocephalus (NPH) Assessed by Insurance Claim Data in Germany

Tms-evoked potentials: Neurophysiological biomarkers for diagnosis and prediction of response to ventriculoperitoneal shunt in normal pressure hydrocephalus

BACKGROUND

Current practice for normal pressure hydrocephalus (NPH) relies upon clinical presentation, imaging and invasive clinical procedures for indication of treatment with ventriculoperitoneal shunt (VPS). We aimed to assess the utility of a TMS-evoked potential (TEP)-based evaluation, for prediction of response to VPS in NPH, as an alternative for the cerebrospinal fluid tap test (CTT).

METHODS

37 "possible iNPH" patients and 16 age-matched healthy controls (HC) were included. All subjects performed Delphi (TMS-EEG and automated analysis of TEP), in response to primary motor cortex (M1) and dorsolateral prefrontal (DLPFC) stimulations. Sixteen patients underwent VPS and response was evaluated with change in modified Rankin Scale (MRS), clinical global impression of change (CGIC) regarding gait and the change on a repeated 3-meter timed up and Go (TUG) after 3 months.

RESULTS

TEP Delphi-NPH index was most successful in discrimination of iNPH responders to VPS (ROC-AUC of 0.91, p = 0.006) compared to other imaging (AUCEI = 0.58, p = 0.58; AUCTH = 0.65, p = 0.32; AUCCA = 0.83, p = 0.03) and TUG tests (AUCTUG = 0.63, p = 0.42; AUCCTT = 0.65, p = 0.35). The TEP M1 P60 and P180 latencies were earlier in responders compared to controls (pM1 P60 = 0.016, pM1 P180 = 0.009, respectively). Also, significant correlations of TEP Delphi measures were registered in comparison to the rank CGIC and magnitude of change in TUG times.

CONCLUSIONS

These initial results suggest that TEPs, may be an alternative for CTT, in prediction of response to VPS in patients suspected as iNPH, exhibiting higher efficacy with reduced patient discomfort and risks, given replication of results in a larger sample and longer follow up times.

Prevalence of idiopathic normal pressure hydrocephalus in older adult population in Shanghai, China: A population-based observational study

INTRODUCTION

Idiopathic normal pressure hydrocephalus (iNPH), a condition that primarily affects the elderly, has an unclear prevalence rate in China.

METHODS

A cross-sectional survey involving 1491 seniors aged 60 and above in Shanghai was conducted. Clinical symptoms and brain imaging data were collected for the diagnosis of suboptimal probable iNPH (s-probable iNPH). The crude prevalence was calculated and the estimated prevalence was inferred.

RESULTS

The crude prevalence of s-probable iNPH was 3.09% and 2.62% respectively, using DESH score ≥6 and Radscale score ≥7 as the primary imaging diagnostic criteria. The estimated prevalence of Shanghai was 2.59% among people over 60 years old and it rose to 7.99% among people aged over 90, and it was estimated that 134,152 and 11,708, respectively, had s-probable iNPH among the corresponding age group.

DISCUSSION

The prevalence of s-probable iNPH fluctuates based on the radiological scoring systems and the defined thresholds employed, and it tends to rise with advancing age.

HIGHLIGHTS

**Significant Prevalence**: The study identified a substantial prevalence of iNPH in older adults, with rates increasing significantly with age, particularly among those aged 90-99 years and centenarians. **Diagnostic Approach**: The research utilized novel diagnostic methodologies by integrating the DESH score or Radscale score with stringent clinical symptoms, providing a closer approximation to the true prevalence of iNPH. **Gender Disparity**: A marked gender difference was observed, with the prevalence of iNPH being significantly higher in males compared to females across all age groups. **Clinical Implications**: The findings underscore the importance of considering iNPH in the differential diagnosis of dementia, particularly among older male patients presenting with cognitive impairment and gait disturbances. **Public Health Impact**: The estimated number of s-probable iNPH patients in Shanghai highlights the need for increased awareness and better management strategies for this underdiagnosed condition in the aging population.

Idiopathic normal pressure hydrocephalus: survey on current diagnostic and therapeutic procedures in clinical practice in Germany

OBJECTIVE

Cerebrospinal fluid (CSF) shunting has become the standard treatment for idiopathic normal pressure hydrocephalus (NPH). Nevertheless, there is still disagreement on diagnostic criteria for selecting patients for surgery and optimal shunt management. The primary aim of the present study was to provide an update on the status of best practice, the use of different diagnostic algorithms and therapeutic management of idiopathic NPH in an European country. METHODS  : A standardized questionnaire with sections on the assessment of clinical symptoms and signs of NPH, diagnostic work-up, therapeutic decision making, and operative techniques was sent to 135 neurosurgical clinics in Germany that regularly perform shunt surgeries.

RESULTS

Overall, responses were received from 114/135 (84.4%) clinics. Most responders considered gait disturbance to be the hallmark clinical sign of idiopathic NPH (96%). A lumbar tap test was utilized always/ mostly by 97 centers (86%). In 43% of the centers, 30-40 ml CSF were removed with the spinal tap test. Spinal dynamic CSF studies were used by 12 centers only occasionally, and only by 1 center always for diagnostic purposes. Ventriculo-peritoneal shunting was the most frequent type of CSF diversion (> 90%). Pressure-controlled valves were used by the majority of units (95%) Overall 102 centers (93%) always/mostly used adjustable valves, and antisiphon devices were used always/ mostly in 50% of units.

CONCLUSION

The present survey demonstrates that there has been a remarkable change of practice and opinions on the diagnosis and treatment of idiopathic NPH over the past two decades in Germany. Remarkably, variabilities in practice among different centers are less common than previously and recommendations according to scientific publications and guidelines have been implemented more readily.

Applied deep learning in neurosurgery: identifying cerebrospinal fluid (CSF) shunt systems in hydrocephalus patients

BACKGROUND

Over the recent decades, the number of different manufacturers and models of cerebrospinal fluid shunt valves constantly increased. Proper identification of shunt valves on X-ray images is crucial to neurosurgeons and radiologists to derive further details of a specific shunt valve, such as opening pressure settings and MR scanning conditions. The main aim of this study is to evaluate the feasibility of an AI-assisted shunt valve detection system.

METHODS

The dataset used contains 2070 anonymized images of ten different, commonly used shunt valve types. All images were acquired from skull X-rays or scout CT-images. The images were randomly split into a 80% training and 20% validation set. An implementation in Python with the FastAi library was used to train a convolutional neural network (CNN) using a transfer learning method on a pre-trained model.

RESULTS

Overall, our model achieved an F1-score of 99% to predict the correct shunt valve model. F1-scores for individual shunt valves ranged from 92% for the Sophysa Sophy Mini SM8 to 100% for several other models.

CONCLUSION

This technology has the potential to automatically detect different shunt valve models in a fast and precise way and may facilitate the identification of an unknown shunt valve on X-ray or CT scout images. The deep learning model we developed could be integrated into PACS systems or standalone mobile applications to enhance clinical workflows.

Normal Pressure Hydrocephalus and Comorbidities: A Quality Study of the University Hospital Münster

OBJECTIVE

Idiopathic normal pressure hydrocephalus (NPH) is commonly accompanied by diverse comorbidities that impact the postoperative course and result in a distinction between shunt responders and shunt non-responders. This study aimed to enhance diagnostics by identifying prognostic differences between NPH patients, individuals with comorbidities, and those with other complications.

METHODS

The data of 119 patients with NPH coding at the University Clinic Münster from January 2009 to June 2017 were examined. The study primarily concentrated on examining symptoms, comorbidities, and radiological measurements, including callosal angle (CA) and Evans index (EI). To evaluate the progression of symptoms, a novel scoring system was developed to quantitatively assess the course at specific time points: 5-7 weeks, 1-1.5 years, and 2.5 years after the operation. This scoring system aimed to provide a standardized approach for measuring and tracking the development of symptoms over time. Logistic regression analyses were employed to identify predictor associated with 3 key outcomes: shunt implantation, surgical success, and the development of complications.

RESULTS

Among the comorbidities observed, hypertension was the most prevalent. Gait disturbance, in the absence of polyneuropathy, was identified as a predictor of a favorable surgical outcome. Hygroma development was associated with a combination of vascular factors and cognitive disorders. The presence of spinal/skeletal changes, diabetes, and vascular constellations were found to increase the likelihood of developing complications.

CONCLUSIONS

The evaluation of comorbidities accompanied by NPH holds significant importance and necessitates meticulous observation, expertise, and multidisciplinary care.

Normal pressure hydrocephalus: Diagnostic delay

Introduction:

Normotensive hydrocephalus is a differential diagnosis in the evaluation of the dementia syndrome. The diagnostic protocols would allow detecting this pathology that has more effective treatment than other dementias.

Objective:

To describe a population with clinical suspicion of normal pressure hydrocephalus evaluated in a Colombian psychiatric hospital and discuss the possible reasons for its diagnostic and therapeutic delay.

Materials and methods:

We conducted a retrospective study of medical records to identify patients with suspected normal pressure hydrocephalus during a 5-year period.

Results:

Thirty-five patients with suspected normal pressure hydrocephalus underwent diagnostic lumbar puncture and five of them were considered candidates for a peritoneal-venous shunt, but none underwent this surgical procedure. After three to six months of the lumbar puncture, the gait pattern improved in 22.8% of the patients, cognition in 22.8%, and sphincter control in 11.4%. Improvement was not sustained in the long term (1 year) in any of them.

Conclusion:

This study suggests the poor implementation of the protocols for evaluating patients with cognitive deficits and delays in the diagnosis of normal pressure hydrocephalus. A small number of patients were identified as candidates for treatment. Normal pressure hydrocephalus is a potentially reversible clinical entity with the placement of a peritoneal ventricular shunt, but delays in diagnosis and treatment have deleterious consequences for patients and their families.

Inpatient diagnoses of idiopathic normal pressure hydrocephalus in the United States: Demographic and socioeconomic disparities

INTRODUCTION

Epidemiology provides an avenue for identifying disease pathogenesis, hence determining national incidence, along with socioeconomic and demographic variables involved in iNPH, can provide direction in elucidating the etiology and addressing healthcare inequalities.

METHODS

To investigate incidence (per 100,000) of iNPH diagnoses applied to the inpatient population, with respect to sex, age, income, residence, and race/ethnicity, we queried the largest American administrative dataset (2008-2016), the National (Nationwide) Inpatient Sample (NIS), which surveys 20% of United States (US) discharges.

RESULTS

Annual national inpatient incidence (with 25th and 75th quartiles) for iNPH diagnoses was 2.86 (2.72, 2.93). Males had an inpatient incidence of 3.27 (3.11, 3.39), higher (p = 0.008) than female at 2.45 (2.41, 2.47). Amongst age groups inpatient incidence varied (p = 0.000004) and was largest amongst the 85+ group at 18.81 (16.40, 19.95). Individuals with middle/high income had an inpatient incidence of 2.96 (2.77, 3.06), higher (p = 0.008) than the 2.37 (2.24, 2.53) of low-income patients. Depending on whether patients lived in urban, suburban, or rural communities, inpatient incidence diverged (p = 0.01) as follows, respectively: 2.65; 2.66; 3.036. Amongst race/ethnicity (p = 0.000003), inpatient incidence for Whites, Blacks, Hispanics, Asian/Pacific Islanders, and Native Americans were as follows, respectively: 3.88 (3.69, 3.93), 1.065 (1.015, 1.14); 0.82 (0.76, 0.85); 0.43 (0.33, 0.52); 0.027 (0.026, 0.12).

CONCLUSION

In the US, inpatient incidence for iNPH diagnoses exhibited disparities between socioeconomic and demographic strata, emphasizing a healthcare inequality. Disproportionately, diagnoses were applied most to patients who were White, male, 65 and older, middle/high income, and living in rural communities.

Prevalence and Trends in Management of Idiopathic Normal Pressure Hydrocephalus in the United States: Insights from the National Inpatient Sample

BACKGROUND

Over the past 2 decades, management of idiopathic normal pressure hydrocephalus (iNPH) has evolved significantly. In the current study, we sought to evaluate the national prevalence and management trends of iNPH in the United States using a national database.

METHODS

The National Inpatient Sample was queried for patients with an International Classification of Diseases diagnosis code for iNPH from 2007 to 2017. Trends in prevalence and procedure type were evaluated per 100,000 discharges and as a percentage of discharges, using weighted discharges. Utilization of procedure type across U.S. regions and hospital types was also compared.

RESULTS

From 2007 to 2017, 302,460 weighted discharges with any diagnosis code for iNPH, aged ≥60 years, were identified. Prevalence ranged from 0.04% to 0.20% (41/100,000 to 202/100,000) among admitted patients ≥60 years old, giving an average prevalence during the study duration of 0.18% (179/100,000). Of 66,759 weighted discharges with a primary diagnosis code of iNPH undergoing surgical management, ventriculoperitoneal shunt (72.0% of discharges, n = 48,977) was most commonly used; of these, 9.3% (n = 4567) were performed laparoscopically. This result was followed by lumbar peritoneal shunt (15.1% of discharges, n = 10,441). Up to 15.1% (n = 9990) of discharges reported only a lumbar puncture, assumed to be only diagnostic, for screening, or part of serial cerebrospinal fluid removal procedures. Significant discrepancies in procedure utilization were also identified among hospitals in the Western, Southern, Northeast and Midwest regions, as well as between urban and rural hospitals (P < 0.05).

CONCLUSIONS

We have summarized the national prevalence of iNPH, trends in its management over the previous decade and trends by region and hospital type.

A Noninvasive Retrograde Flushing System for Shunted Hydrocephalus: Initial Case Series of 25 Patients

Hydrocephalus is a common neurosurgical pathology associated with high patient morbidity and systemwide healthcare costs. A significant portion of these costs are related to the failure of ventricular shunting systems. Despite decades of research and technological development, the rate of shunt failure and revision has not significantly improved. The Reflow™ Ventricular System (Anuncia, Inc., Lowell, MA) is a recent technological development with the potential to prolong the shunt lifespan. This system introduces a noninvasive means of flushing a shunt proximally with a controlled, repeatable pulse of cerebral spinal fluid (CSF) and of creating a new ventricular opening for occluded shunts. In this multicenter case series, we present the early clinical experiences with this device and discuss its potential.

Role of psychiatric, cardiovascular, socioeconomic, and demographic risk factors on idiopathic normal pressure hydrocephalus: A retrospective case-control study

OBJECTIVES

Currently, predicting and preventing idiopathic normal pressure hydrocephalus (iNPH) remains challenging, especially for patients without a history of cerebrovascular disease. By exploring the role of cardiovascular and psychiatric history, demographics, and socioeconomic status in iNPH, will provide better direction for elucidating the etiology or addressing healthcare inequalities.

PATIENTS AND METHODS

To investigate iNPH with respect to the selected risk factors, we conducted a retrospective case-control study from a neuroscience institute in Hawaii with a patient pool of 25,843. After excluding patients with a history of cerebrovascular disease, we identified 29 cases which meet the American-European guidelines for iNPH diagnosis. Meanwhile, 116 controls matched to age, sex, and race were also randomly selected.

RESULTS

Median age at diagnosis was 83 (IQR: 74-88), with cases estimated 22 years older than controls (95 % CI: 14.00-29.00; p = 0.0000001). Patients with iNPH were more likely to be White (OR 4.01, 95 % CI: 1.59-10.11; p = 0.0042) and less likely Native Hawaiian and other Pacific Islander (OR 0.010, 95 % CI: 0.00-0.78; p = 0.014). Median household income was $2874 (95 % CI: 0.000089-6905; p = 0.088) greater amongst iNPH cases. Effect size amongst cardiovascular risk factors was not found statistically significant (i.e., body mass index, hyperlipidemia, type 2 diabetes mellitus, hypertension, coronary artery disease or prior myocardial infarction history, peripheral vascular disease, smoking status, congestive heart failure, atrial fibrillation/flutter, and history of prosthetic valve replacement). However, iNPH patients were more likely to have a history of alcohol use disorder (OR 8.29, 95 % CI: 0.99-453.87; p = 0.050) and history of a psychiatric disorder (OR 2.48; 95 % CI: 1.08-5.68; p = 0.029). Odds ratio for autoimmune disorder, thyroid disorder, glaucoma, and seizures did not reach statistical significance.

CONCLUSION

Patient race (i.e., White; Native Hawaiian or other Pacific Islander) was found associated with iNPH development. Meanwhile, after excluding those with cerebrovascular disease, cardiovascular risk factors were not found associated with iNPH. Lastly, iNPH cases were more inclined to have a history of alcohol use disorder and prior psychiatric disorder. Overall, this data reveals that a racial disparity exists amongst iNPH, as well as highlights the role of various cardiovascular and psychiatric risk factors, which can potentially provide direction in etiology elucidation.

The efficacy and limitation of lumboperitoneal shunt in normal pressure hydrocephalus

OBJECTIVE

To investigate whether the efficacy of the lumbar-peritoneal (LP) shunt is sustainable, we measured the outcomes of patients with idiopathic NPH (iNPH) preoperatively and postoperatively.

PATIENTS AND METHODS

We retrospective reviewed records of 58 patients with iNPH from 2013 to 2015. Exclusion of 7 patients expired, 1 patient shunt infection, and 8 patients was loss of follow-up. In the remaining 42 patients, the mood, talking response, movement, attention, recalling memory, and mini-mental state examination (MMSE), representing patient outcomes, were measured. All of whom were follow-up for 3 years.

RESULTS

Mood (1.91 ± 0.30), talking response (1.98 ± 0.15), movement (1.71 ± 0.51), attention (1.95 ± 0.22), and recalling memory (1.86 ± 0.35) were significantly improved after surgery (1 week;p <  0.0001). However, the indicators significantly declined after 3 years (mood: 0.31 ± 0.52, talking response: 0.50 ± 0.59, movement: 0.17 ± 0.38, attention: 0.40 ± 0.59, recalling memory: 0.21 ± 0.42). The MMSE was also significantly improved after 3 months of surgery (17.9 5 ± 2.80 vs. 25.02 ± 3.36; p <  0.0001). However, it declined after 3 years (17.83 ± 3.66; p = 0.83).

CONCLUSION

The iNPH is considered potentially reversible. Our data supported that the LP shunt was efficient in the short term. However, the neurological degeneration was still progressive.

Secondary deterioration in patients with normal pressure hydrocephalus after ventriculoperitoneal shunt placement: a proposed algorithm of treatment

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.

A systematic review on the epidemiology of normal pressure hydrocephalus

BACKGROUND

The aim of this systematic review is to gather all available studies reporting prevalence and incidence rates of iNPH and to assess their methodological quality and consistency.

METHODS

All available studies published up to June 2019 were retrieved searching the databases PubMed, ISI Web of Science, and the Cochrane Database of Systematic Reviews. All included studies were qualitatively assessed by two independent reviewers using the MORE Checklist for Observational Studies of Incidence and Prevalence.

KEY RESULTS

Bibliographic searches and other sources yielded 659 records. A total of 28 studies were selected and applied the predefined inclusion and exclusion criteria. Fourteen studies were further excluded, and 14 studies (10 on prevalence and 6 on incidence) were included in the qualitative analysis. Results from the prevalence studies reported crude overall rates ranging from 10/100 000 to 22/100 000 for probable iNPH and 29/100 000 for possible iNPH, and age-specific rates ranging from 3.3/100 000 in people aged 50-59 to 5.9% in people aged ≥ 80 years. Results from incidence studies reported overall crude rates ranging from 1.8/100 000 to 7.3/100 000 per year, and age-specific rates ranging from 0.07/100 000/year in people aged < 60 years to 1.2/1000/year in people aged ≥ 70 years.

CONCLUSIONS & INFERENCES

The high methodological and clinical heterogeneity of included studies does not allow drawing adequate conclusions on the epidemiology of iNPH. Further, high-quality, population-based studies should be carried out to allow for a better understanding of the epidemiology of this condition. Moreover, the implementation in current clinical practice of guidelines on the diagnosis and management of iNPH should also be endorsed.

Current epidemiology of cerebrospinal fluid shunt surgery in the UK and Ireland (2004-2013)

OBJECTIVES

To determine current epidemiology and clinical characteristics of cerebrospinal fluid (CSF) shunt surgery, including revisions.

METHODS

A retrospective, multicentre, registry-based study was conducted based on 10 years' data from the UK Shunt Registry, including primary and revision shunting procedures reported between 2004 and 2013. Incidence rates of primary shunts, descriptive statistics and shunt revision rates were calculated stratified by age group, geographical region and year of operation.

RESULTS

41 036 procedures in 26 545 patients were submitted during the study period, including 3002 infants, 4389 children and 18 668 adults. Procedures included 20 947 (51.0%) primary shunt insertions in 20 947 patients, and 20 089 (49.0%) revision procedures. Incidence rates of primary shunt insertions for infants, children and adults were 39.5, 2.4 and 3.5 shunts per 100 000 person-years, respectively. These varied by geographical subregion and year of operation. The most common underlying diagnoses were perinatal intraventricular haemorrhage (35.3%) and malformations (33.9%) in infants, tumours (40.5%) and malformations (16.3%) in children, and tumours (24.6%), post-haemorrhagic hydrocephalus (16.2%) and idiopathic normal pressure hydrocephalus (14.2%) in adults. Ninety-day revision rates were 21.9%, 18.6% and 12.8% among infants, children and adults, respectively, while first-year revision rates were 31.0%, 25.2% and 17.4%. The main reasons for revision were underdrainage and infection, but overdrainage and mechanical failure continue to pose problems.

CONCLUSIONS

Our report informs patients, carers, clinicians, providers and commissioners of healthcare, researchers and industry of the current epidemiology of shunting for CSF disorders, including the potential risks of complications and frequency of revision.

Global hydrocephalus epidemiology and incidence: systematic review and meta-analysis

OBJECTIVE

Hydrocephalus is one of the most common brain disorders, yet a reliable assessment of the global burden of disease is lacking. The authors sought a reliable estimate of the prevalence and annual incidence of hydrocephalus worldwide.

METHODS

The authors performed a systematic literature review and meta-analysis to estimate the incidence of congenital hydrocephalus by WHO region and World Bank income level using the MEDLINE/PubMed and Cochrane Database of Systematic Reviews databases. A global estimate of pediatric hydrocephalus was obtained by adding acquired forms of childhood hydrocephalus to the baseline congenital figures using neural tube defect (NTD) registry data and known proportions of posthemorrhagic and postinfectious cases. Adult forms of hydrocephalus were also examined qualitatively.

RESULTS

Seventy-eight articles were included from the systematic review, representative of all WHO regions and each income level. The pooled incidence of congenital hydrocephalus was highest in Africa and Latin America (145 and 316 per 100,000 births, respectively) and lowest in the United States/Canada (68 per 100,000 births) (p for interaction < 0.1). The incidence was higher in low- and middle-income countries (123 per 100,000 births; 95% CI 98-152 births) than in high-income countries (79 per 100,000 births; 95% CI 68-90 births) (p for interaction < 0.01). While likely representing an underestimate, this model predicts that each year, nearly 400,000 new cases of pediatric hydrocephalus will develop worldwide. The greatest burden of disease falls on the African, Latin American, and Southeast Asian regions, accounting for three-quarters of the total volume of new cases. The high crude birth rate, greater proportion of patients with postinfectious etiology, and higher incidence of NTDs all contribute to a case volume in low- and middle-income countries that outweighs that in high-income countries by more than 20-fold. Global estimates of adult and other forms of acquired hydrocephalus are lacking.

CONCLUSIONS

For the first time in a global model, the annual incidence of pediatric hydrocephalus is estimated. Low- and middle-income countries incur the greatest burden of disease, particularly those within the African and Latin American regions. Reliable incidence and burden figures for adult forms of hydrocephalus are absent in the literature and warrant specific investigation. A global effort to address hydrocephalus in regions with the greatest demand is imperative to reduce disease incidence, morbidity, mortality, and disparities of access to treatment.

Ventricular Volume Dynamics During the Development of Adult Chronic Communicating Hydrocephalus in a Rodent Model

INTRODUCTION

The pathophysiology of normal-pressure hydrocephalus and the correlation with its symptomatology is not well understood.

OBJECTIVE

To monitor and evaluate the enlargement patterns of the ventricular system for each ventricle and its correlation with the presenting symptoms.

METHODS

Bilateral kaolin injection into the subarachnoid space overlying the cranial convexities was done in 18 adult rats. Magnetic resonance imaging was performed on an 11.7-T scanner 15, 60, 90, and 120 days after injection. Volumes of the ventricular system were measured for each ventricle and correlated with biweekly behavioral findings.

RESULTS

There was a progressive increase in the ventricular volume for the lateral ventricles since day 15 in the kaolin-injected animals. There was a nonsignificant trend in volume growth for the third ventricle, but its enlargement was synchronous with the lateral ventricles. No significant change for the fourth ventricle. No symptoms were detected in the first 60 days. Association was found between the ventricular volume and locomotor changes. In addition, the odds of locomotor symptoms increased by 3% for every additional cubic millimeter of volume in the left (P < 0.001) and right (P = 0.023) ventricles, and for the total magnetic resonance imaging volume by 1% (P = 0.013).

CONCLUSIONS

Expansion of the lateral ventricles maintained similar proportions over time, accompanied by a synchronous third ventricular expansion with less proportion and a nonsignificant fourth enlargement. Lateral ventricles enlarged most in those animals that were to develop late locomotor deterioration. Further research using this animal model combined with different radiologic imaging techniques, such as diffusion tensor imaging and perfusion studies, is recommended.

Shunt Intervention for Possible Idiopathic Normal Pressure Hydrocephalus Improves Patient Outcomes: A Nationwide Hospital-Based Survey in Japan

Background and Purpose: This study aimed to investigate the efficacy of cerebrospinal fluid shunt intervention for idiopathic normal pressure hydrocephalus (iNPH) using data from a nationwide epidemiological survey in Japan.

Methods: We conducted a cross-sectional study using data from a nationwide epidemiological survey performed in Japan. Propensity score matching was used to select 874 patients from 1,423 patients aged ≥60 years, who were diagnosed with iNPH based on clinical guidelines following a hospital visit in 2012. Patients who experienced an improvement of at least 1 modified Rankin Scale (mRS) grade after the intervention were classified as “improved,” while the remaining patients were classified as “non-improved.” In the shunt intervention (n = 437) and non-shunt intervention (n = 437) groups, the differences in mRS grade improvement were analyzed using the Mann-Whitney U-test. Finally, we examined subjects in the shunt intervention group (n = 974) to compare the outcomes and complications of ventriculoperitoneal (VP) shunt (n = 417) with lumboperitoneal (LP) shunt (n = 540).

Results: We examined subjects with iNPH to compare the non-shunt intervention group to the shunt intervention group following adjustment for age and mRS grade at baseline by propensity score matching (0.31–0.901). The mRS grade (mean [SD]) was found to improve with non-shunt intervention (2.46 [0.88]) and shunt intervention (1.93 [0.93]) (p < 0.001) in iNPH patients. The mRS outcome score and complications comparison between the VP and LP shunt groups did not show significant difference.

Conclusions: In this study, analysis of the efficacy of shunts for possible iNPH conducted in Japan indicated a significant improvement in the mRS grade between baseline and outcome within 1 year, regardless of the surgical technique, and shunt intervention was found to be effective.

[Idiopathic normal pressure hydrocephalus: High incidence in people over 80 years of age]

INTRODUCTION

Idiopathic normal pressure hydrocephalus is usually observed in adults over 60 years of age. The highest incidence of cases is between 70 and 80 years-old, and it could be under-diagnosed in over 80 year-olds.

OBJECTIVE

A description is presented on the overall incidence and age group incidence, the delay in the diagnosis, and main outcomes.

PATIENTS AND METHODS

A descriptive study was performed on patients with idiopathic normal pressure hydrocephalus, in the population of Osona County during the years 2010-2015.

RESULTS

The annual incidence rate was 4.43 per 100,000 inhabitants. The incidence increased with age; from 8.09 per 100,000 in the 60 to 69 years age group, to 23.61 per 100,000 in the 70-79 years age group of, and to 37.02 per 100,000 in the 80-89 years age. The delay in the diagnosis was 15.01 ± 10.35 months. All the patients improved after surgery, but only 73.3% of the patients maintained the improvement after one year.

CONCLUSIONS

Idiopathic normal pressure hydrocephalus is an age related disease and probably underdiagnosed in the elderly. An early diagnosis and a clinical suspicion are essential in patients over 80 years old.

Nationwide hospital-based survey of idiopathic normal pressure hydrocephalus in Japan: Epidemiological and clinical characteristics

OBJECTIVES

There have been no nationwide epidemiological studies of idiopathic normal pressure hydrocephalus (iNPH) in Japan. Therefore, a nationwide epidemiologic survey of iNPH was performed to determine the number of cases and clinical characteristics by sex and diagnostic level.

METHODS

The first survey examined the numbers of cases that met the diagnostic criteria of iNPH and those who underwent shunt operations in 2012. The second survey gathered patients' details to clarify their clinical background characteristics.

RESULTS

The estimated number of cases meeting the diagnostic criteria in 2012 was 12,900, with 6,700 undergoing shunt operations. The estimated crude prevalence was 10.2/100,000 persons. The age of onset was in the 70s in more than 50% of both men and women. Significantly higher (p < .05) frequencies of gait impairment in men and cognitive decline in women were observed as initial symptoms. At the time of definitive diagnosis, gait impairment was observed most frequently in patients with definite iNPH (77.7%). Hypertension was the most frequent comorbidity (40.0%), followed by diabetes mellitus (17.8%) and Alzheimer's disease (14.8%). Hypertension was observed more frequently in men, but diabetes was observed more frequently in women (p < .05). An LP shunt was the first-choice (55.1%) treatment of iNPH, followed by a VP shunt (43.2%).

CONCLUSION

This study showed that iNPH occurs most frequently in the 70s, gait impairment and cognitive decline are the most frequent initial symptoms in men and women, respectively, and hypertension and diabetes are the most frequent comorbidities in men and women, respectively.