Diagnosis Of Normal Pressure Hydrocephalus Research Articles

A Brief Review on Normal Pressure Hydrocephalus Diagnosis in Primary Neuropsychiatric Care Settings

Normal pressure hydrocephalus (NPH) is clinically characterized by the triad of mental deterioration, gait disturbance, and urinary incontinence. Correct diagnosis and referral of patients is important because NPH is a potentially treatable cause of cognitive decline and should be distinguished from more common forms of irreversible dementia. Unfortunately, it remains to be a rather underdiagnosed and controversial neuropsychiatric entity even in countries with modern healthcare systems. The diagnostic process is complicated by diverse clinical presentations, especially when the classical triad is incomplete or atypical such as with psychiatric symptoms. This manuscript aims to briefly review atypical clinical presentations of NPH and basic radiologic findings associated with it, and outline some recommendations to primary care physicians for diagnosis and referral.

Ứng dụng của test chọc tháo dịch não tủy trong chẩn đoán và điều trị giãn não thất áp lực bình thường nguyên phát: ca lâm sàng

Normal Pressure Hydrocephalus (NPH) is a clinical syndrome characterized by gait disturbance, cognitive decline, and urinary incontinence accompanied by ventricular enlargement without increased intracranial pressure. NPH is a diagnosis of particular note as it differs from other neurodegenerative disorders such as Alzheimer’s and Lewy body disease. Symptoms may improve if diagnosed and treated promptly. Clinical symptoms of the disease were first described by Salomon Hakim and R.D. Adam in 1965, though they are common but not specific enough. Additionally, age-related ventricular enlargement and periventricular white matter damage are found in various conditions, both in normal individuals and in other cognitive decline disorders (vascular cognitive impairment, Alzheimer’s), making early diagnosis challenging. Treatment of NPH mainly relies on surgical intervention with ventriculoperitoneal shunting, with accurate preoperative diagnosis being crucial for success.Lumbar puncture (LP) can be considered the most important procedure to demonstrate the underlying pathophysiology of NPH, which is normal pressure hydrocephalus. High-volume lumbar tap test (LTT) is a relatively simple and effective method when clinical-radiological suspicion is present: it helps to distinguish NPH from other conditions with ventricular enlargement and aids in predicting the success of ventriculoperitoneal shunting surgery. The clinical case presented below illustrates the value of LTT in the definitive diagnosis of NPH at the Department of Neurology and Alzheimer’s Disease - National Geriatric Hospital.

Cognitive changes after tap test in patients with normal pressure hydrocephalus: a before-and-after study

Normal pressure hydrocephalus (NPH) leads to cognitive impairment (CI) as part of its triad of symptoms. Assessment of CI before and after a tap test can be used to inform diagnosis, differentiate NPH symptoms from alternative or concomitant causes of CI, and suggest the potential benefits of valve placement. The aims of this study are: to describe cognitive performance in patients with NPH diagnosis before and after a tap test, and to compare CI between patients with NPH meeting criteria for a dementia diagnosis (D +) and those without criteria for dementia (D−) at both baseline and after the tap-test. We performed a Before-and-after study evaluating clinical features and performance on cognitive tests (CERAD, ADAS-COG, SVF, PVF, ROCF and IFS). We included 76 NPH patients, with a median age of 81 years. 65 patients (87.8%) improved cognitive performance after tap test. ROCF (p = 0.018) and IFS (p < 0.001) scores significantly change after the tap test. Dementia was concomitant in 68.4% of patients. D + group showed higher proportion of patients with altered performance in IFS, PVF, SVF, and ROCF than D- group at baseline (p < 0.05). A significant improvement in SVF and IFS was observed exclusively in the D− group after tap test. Our results suggest that executive function and praxis are the cognitive domains more susceptible to improvement after a tap test in a 24-h interval in NPH patients. Moreover, the D− group showed a higher proportion of improvement after the tap test in executive function and verbal fluency test compared with the D + group.

17 years of experience with shunt systems in normal pressure hydrocephalus - From differential pressure to gravitational valves

ObjectiveComplication rate of shunting for normal pressure hydrocephalus (NPH) has significantly improved over the last decades. Especially the use of overdrainage protection has reduced the incidence of subdural hematoma and collections. However, gravitational valves were associated with other complications of shunt dysfunction. We present our 17 years of experience with patients with normal pressure hydrocephalus who changed from a differential pressure valve to a gravitational valve system. MethodsWe retrospectively identified all patients with the diagnosis of normal pressure hydrocephalus, in whom primary shunt implantation was performed between 2004 and 2020. Shunt implantation was performed as per our internal standard. Review of imaging, charts and patient reports was performed. ResultsIn total, 409 patients were included in the analysis. Mean age was 73.0 ± 7.1years. Between 2004 and 2010, predominantly Hakim valves (n = 100, 24.4%) were implanted, whilst from 2009 until 2020, proGAV valves (n = 296, 72.4%) were used. Mean follow-up was 8.9 ± 4.5 years. Initial subjective improvement of symptoms was reported in 69.9%, whilst this number decreased at the last follow-up to 29.8%. No significant differences were observed between the valves in the frequency of surgery for subdural hematoma. Shunt assistant implantation was performed in 17% of patients with Hakim valve, in 9.5% of patients with proGAV, a shunt assistant was added. Shunt obstruction was significantly higher in proGAV valves (p < 0.001). ConclusionsOur findings confirm the observation of frequent overdrainage in shunts without anti-siphon/gravitational component. Gravitational valves on the other hand may be associated with more obstruction.

The Diagnostic Accuracy of Artificial Intelligence in Radiological Markers of Normal-Pressure Hydrocephalus (NPH) on Non-Contrast CT Scans of the Brain.

Diagnosing normal-pressure hydrocephalus (NPH) via non-contrast computed tomography (CT) brain scans is presently a formidable task due to the lack of universally agreed-upon standards for radiographic parameter measurement. A variety of radiological parameters, such as Evans' index, narrow sulci at high parietal convexity, Sylvian fissures' dilation, focally enlarged sulci, and more, are currently measured by radiologists. This study aimed to enhance NPH diagnosis by comparing the accuracy, sensitivity, specificity, and predictive values of radiological parameters, as evaluated by radiologists and AI methods, utilizing cerebrospinal fluid volumetry. Results revealed a sensitivity of 77.14% for radiologists and 99.05% for AI, with specificities of 98.21% and 57.14%, respectively, in diagnosing NPH. Radiologists demonstrated NPV, PPV, and an accuracy of 82.09%, 97.59%, and 88.02%, while AI reported 98.46%, 68.42%, and 77.42%, respectively. ROC curves exhibited an area under the curve of 0.954 for radiologists and 0.784 for AI, signifying the diagnostic index for NPH. In conclusion, although radiologists exhibited superior sensitivity, specificity, and accuracy in diagnosing NPH, AI served as an effective initial screening mechanism for potential NPH cases, potentially easing the radiologists' burden. Given the ongoing AI advancements, it is plausible that AI could eventually match or exceed radiologists' diagnostic prowess in identifying hydrocephalus.

Prevalence of Fecal Incontinence in Normal Pressure Hydrocephalus: A Prospective Evaluation of 100 Patients

Normal pressure hydrocephalus (NPH) is a frequent disease in elderly patients. The main symptoms are gait disturbance, urine incontinence, and cognitive decline. Fecal urgency and incontinence are described as rare additional symptoms; however, no exact numbers are known. The aim of this study was to investigate the prevalence of fecal disturbances in NPH patients. Patients who presented to our department with confirmed diagnosis of NPH between January and December 2021 were interviewed prospectively about fecal function. Additionally, the extent of gait disturbance, cognitive decline, ventriculomegaly (EvansIndex), disproportionate enlarged subarachnoid space hydrocephalus (DESH presence), age, gender, and length of history were documented. In those who were operated with a hydrocephalus shunt postoperative development of stool incontinence was followed up. One hundred patients were evaluated (67 males, 33 females, medium age 77.5years, medium Evans Index: 0.37; 87 with disproportionate enlarged subarachnoid space hydrocephalus). 97 patients showed gait disturbance, 84 cognitive decline, and 87 bladder dysfunctions. 78 patients had the complete Hakim triad. 32 patients complained about fecal incontinence (20 with urge incontinence, 12 with complete incontinence). Twenty nine patients were shunted, of which 17 (57%) recovered completely, 9 (31%) partially, and 3 (10%) did not show any change. Fecal urgency and incontinence is a frequent finding in NPH (32%) and is essential for the quality of life. In the general population, fecal incontinence in elderly is found in up to 15%. The more than two-fold higher prevalence in NPH patients and the high percentage of postshunted improvement suggests that NPH causes often directly fecal disturbance.

Evaluation of the Evan’s and Bicaudate index for South Karnataka Population using computed tomography

Background: Radiological markers that are useful in the diagnosis of normal pressure hydrocephalus include the Bicaudate index (BCI) and the Evans index (EI), which are practical indicators of ventricular volume. Worldwide, variation exists in normative studies for both these indices. The majority of research for EI and BCI is based on data from the Western population. The study has been performed on the South Karnataka population. Aims and Objectives: This study’s goal is to derive age and gender specific cutoff values on normative data of Evans and BCI. Materials and Methods: This was a prospective and observational study.Patients referred to “RL Jalappa Hospital” for computed tomography (CT) scan of the brain who meet the inclusion criteria will be included in this study. CT brain of all the patients will be performed in Siemens Somatom emotion 16 slice CT scanner. Ninety-seven were selected for this study, and EI and BCI were calculated for them. Results: The mean value of EI and BCI in our study was 0.26±0.02 and 0.1167±0.02, respectively. The difference in EI and BCI between males and females shown significant statistical difference between males and females but the values increased as increase in age. Conclusion: Our study for South Indian population concludes that EI and BCI have a significant statistical difference between males and females. Both EI and BCI values increase with age. Hence cutoff values of EI and BCI index according to age and gender are important for evaluation of hydrocephalus.

Cerebrospinal fluid transcripts may predict shunt surgery responses in normal pressure hydrocephalus.

Molecular biomarkers for neurodegenerative diseases are critical for advancing diagnosis and therapy. Normal pressure hydrocephalus (NPH) is a neurological disorder characterized by progressive neurodegeneration, gait impairment, urinary incontinence and cognitive decline. In contrast to most other neurodegenerative disorders, NPH symptoms can be improved by the placement of a ventricular shunt that drains excess CSF. A major challenge in NPH management is the identification of patients who benefit from shunt surgery. Here, we perform genome-wide RNA sequencing of extracellular vesicles in CSF of 42 NPH patients, and we identify genes and pathways whose expression levels correlate with gait, urinary or cognitive symptom improvement after shunt surgery. We describe a machine learning algorithm trained on these gene expression profiles to predict shunt surgery response with high accuracy. The transcriptomic signatures we identified may have important implications for improving NPH diagnosis and treatment and for understanding disease aetiology.

Normal Pressure Hydrocephalus: Clinical Approach and Practical Considerations

Normal pressure hydrocephalus is defined as an abnormal cerebrospinal fluid accumulation in the ventricles. The condition is more commonly seen in the elderly population. It is present in more than 700,000 Americans between the ages of 60 - 70, but less than 20% receive an accurate diagnosis. It may be idiopathic without a known cause or the result of any circumstance that interferes with the normal cerebral spinal fluid flow (i.e., subarachnoid hemorrhage, head trauma, infection, tumor, or complications from surgery). Clinical manifestations include the presence of cognitive impairment, gait disturbance, and urinary incontinence. The diagnosis of normal pressure hydrocephalus is complex since it may present similar symptoms to those associated with other neurological conditions, particularly dementia syndromes. Therefore, a combination of classic clinical presentation, brain imaging findings, and dynamic evaluation of cerebrospinal fluid is necessary to identify this disorder. Depending on the patient’s characteristics, medical/conservative treatment or ventriculoperitoneal surgical shunting can be effective management methods. On an individual basis, the prognosis of the disease and the outcome of treatment may vary.

Comparison Between Ventricular and Spinal Infusion Tests in Suspected Normal Pressure Hydrocephalus.

Idiopathic normal pressure hydrocephalus (iNPH) is an often-overlooked or misdiagnosed brain disorder characterized by overt ventriculomegaly and associated with gait disturbances, cognitive impairment, and urinary incontinence. If correctly diagnosed, it is considered the only form of dementia treatable with surgery, namely through a ventriculoperitoneal or ventriculoatrial shunt with programmable valves.Among the 856 spinal and ventricular infusion tests performed from 2001 to 2017 at our institution, we analyzed 106 cases selected for suspected normotensive hydrocephalus. In all cases, Intracranial Elastance Index (IEI) and outflow resistance (Rout) values were calculated: 52 of these patients underwent Spinal Katzman Test (SKT), and the remaining 54 underwent an intraventricular infusion test (IVKT). Of the 40 patients in the SKT group with pathological elastance (71%), 17 also had a Rout >12mmHg and 23 a Rout <12mmHg. Of the 50 patients in the IVKT group with pathological elastance (92%), 38 also had a Rout >12mmHg and 12 a Rout <12mmHg.IVKT and SKT to date represent two useful tools in the diagnosis of normal pressure hydrocephalus. Despite being more invasive, IVKT, including both the intracranial elastance index (IEI) and Rout analysis, could be considered more reliable than SKT and therefore could be reserved for the most controversial cases.

Accuracy of MRI CSF Flowmetry in the Diagnosis of Normal Pressure Hydrocephalus

BACKGROUND: Normal pressure hydrocephalus (NPH) is one of the few treatable causes of dementia. NPH is diagnosed using the clinical triad of: Gait disturbance, progressive mental deterioration, urinary urgency, or incontinence in association with radiological findings suggestive of NPH, for example, ventriculomegaly, disproportionately enlarged subarachnoid space hydrocephalus, and narrow callosal angles. AIM: The purpose of the present study was to assess the accuracy of MRI cine phase flow studies as a non-invasive modality in the diagnosis, and also for the prediction of improvement of symptoms suggestive of NPH without the need for CSF tapping. METHODS: Twenty-six patients suffering clinically from the triad of NPH, or at least two of them; attending our neurology, psychiatry, and neurosurgery clinics in Cairo University Hospitals, with ages ranging between 50 and 85 years, randomly chosen regarding sex or other comorbidities. All patients underwent a regular MRI in addition to CSF flowmetry studies to correlate the MRI findings that reveal NPH with their known clinical features. Careful clinical assessment was performed to detect severity of symptoms, and patients were classified accordingly, and a disability score was provided. After CSF tapping, patients were reassessed clinically after 6–8 h to detect improvement of symptoms, and the degree of improvement was compared to the result of CSF flow study. RESULTS: CSF flow studies, particularly stroke volume across the aqueduct of Sylvius, provide the highest significance in diagnosing hyperdynamic circulation evident by many radiological studies in cases of NPH. This was also found to be a good prognostic factor which correlates well with the improvement of symptoms following CSF tapping. However, its use to exclude suspicious cases of NPH seems unreliable, that is, not a good negative predictor. Findings of MRI CSF flow studies also show significance in detecting brain atrophic changes, especially peak systolic velocity, which usually accompany or mimic the clinical picture of NPH. CONCLUSION: MRI CSF flow studies are an excellent aid as an adjuvant non-invasive technique in selection of suspicious cases as it shows significance in detecting hyperdynamic circulation, especially high stroke volume results in cases of NPH. Both CSF tapping and CSF flowmetry findings “low stroke volume values” were not found to be a good negative predictor for clinical improvement after shunting.

Lumboperitoneal Shunt Preference in Treatment of Patients with Normal Pressure Hydrocephalus

Objective: To demonstrate the advantages of Lumboperitoneal (LP) shunt surgery applied to patients with normal pressure hydrocephalus (NPH).Methods: Preoperative, intraoperative and postoperative data of 20 patients who underwent LP shunt surgery for NPH between 01/01/2012 and 07/04/2022 at the Neurosurgery Clinic of Ordu University Training and Research Hospital were analyzed. The demographic, clinical and laboratory data of the patients as well as their medical records were reviewed. Patients who underwent LP shunt with the diagnosis of normal pressure hydrocephalus in our clinic were screened retrospectively, and the success rates and complications after the surgical intervention applied to these patients were recorded.Results: Statistically significant improvements were recorded in Modified Ranking Scale Scores and Mini-Mental State Examination Scores at the end of the first year. The incidence of Gait Disturbance did not differ significantly by gender, The incidence of dementia did not differ significantly by gender, The incidence of urinary incontinence showed a significant change according to gender While all of the women diagnosed with normal pressure hydrocephalus had urinary incontinence in the preoperative period, this rate was seen in only 66.7% of the men. Gait disturbance improved in 80%, urinary incontinence in 60%, and cognitive functions in 60% of patients. No neurogenic complication developed in our operated patients. Wound infection occurred at the abdominal incision site in only two patients (10%). Subcutaneous hematoma occurred in the abdominal region in one patient (5%). Conclusion: LP shunt surgery has a lower complication rate than VP shunt surgery and is a more easily applicable surgical technique. LPS surgery is a safe and minimally invasive treatment method. It has lower complication rates compared to VPS . LPS surgery is an effective surgical technique. It can be used as an alternative to the VPS procedure in the treatment of NPH patients

Normal pressure hydrocephalus: Neurophysiological and neuropsychological aspects: a narrative review.

Idiopathic normal pressure hydrocephalus (NPH) is a syndrome that affects elderly people and is characterized by excessive accumulation of cerebrospinal fluid in the brain ventricles. Diagnosis is based on the evaluation of clinical symptoms, which consists of a classic triad (Hakim triad), gait disturbances, cognitive impairment, and urinary incontinence. However, this complete triad is not always seen; therefore, it is difficult to make the diagnosis. NPH can be divided into primary or idiopathic NPH and secondary NPH. Diagnostic criteria for NPH remain a topic of discussion; however, the development of diagnostic techniques has brought new opportunities for diagnosis. The aim of this review is to present an overview of neurophysiological and neuropsychological approaches to support the clinical evaluation of patients with NPH and contribute to the differential diagnosis of NPH and dementia, as the clinical symptoms of NPH may resemble other neurodegenerative disorders.

428 The Lumbar Tap Trial Experience: An Analysis of Outcomes in 133 Adult Normal Pressure Hydrocephalus Patients Undergoing 2-Day Lumbar Tap Trial at a Single Center

INTRODUCTION: Lumbar Tap Trial (LTT) with high volume cerebrospinal fluid (CSF) removal is one of the primary adjunct testing modalities at a neurosurgeon’s disposal in the diagnosis of normal pressure hydrocephalus (NPH). Patients responsive to LTT may receive permanent fluid diversion by way of shunt placement. METHODS: Retrospective review of the electronic medical records of 133 patients that underwent a 2-day LTT by a single surgeon at our adult hydrocephalus center was conducted. Each patient has been closely followed at our hydrocephalus clinic from the time of symptomatic presentation through LTT, eventual shunt placement (if performed), and frequent post-operative assessments. Assessment of improvement during LTT and following shunt placement includes a timed 25 ft. walk test at our clinic. RESULTS: From 2016 – present, 133 patients have undergone 136 completed LTTs. During initial LTT, no major complications such as death, infection, hemorrhage, or nerve-root injury were seen. Minor complications included post-tap low back pain, headache, and transient nerve-root irritation. Average improvement during timed 25 ft. walk test was 6.6 sec following LTT. Average improvement in timed walk test in patients receiving shunt placement was 13.9 sec compared to post LTT walk time. CONCLUSION: In patients with suspected NPH, high-volume LTT was found to be an effective and safe diagnostic tool in our patient population. Patients demonstrating significant objective improvement during a timed walk test are frequently recommended for shunting. Patients undergoing shunt placement following improvement on LTT continued to improve with a mean decrease in walk time post-operatively, highlighting the effectiveness of LTT in predicting symptomatic response to shunt placement.

Clinical Outcomes of Shunting in Normal Pressure Hydrocephalus: A Multicenter Prospective Observational Study.

Background: Normal pressure hydrocephalus (NPH) is characterized by the triad of dementia, gait disturbance and urinary incontinence, all potentially reversible following a ventriculoperitoneal shunt (VPS). This study aims to evaluate the clinical outcomes of shunting in normal pressure hydrocephalus following a new standardized protocol. Methods: This study is designed according to the STROBE guidelines. Demographical, clinical, surgical and radiological data were collected from May 2015 to November 2019. Gait, balance and incontinence data based on the NPH European scale were collected before and after one, six and twelve months of treatment with a VPS. Clinical symptoms and changes of the stoke volume, measured on phase-contrast MRI, were used to evaluate improvement after VPS surgery. Results: One hundred and eighty-one consecutive patients met the inclusion criteria. The mean age was 73.1 years (59–86) and mean follow-up was 38.3 months (13–50). The gait (58.5 ± 14.3 to 70.1 ± 13.4, p < 0.001), the balance (66.7 ± 21.5 to 71.7 ± 22.1, p = 0.001), continence domain (69.9 ± 20.5 to 76 ± 20, p = 0.002) scores and neuropsychological scales showed a statistically significant improvement over the follow-up. The overall improvement after 12 months was present in 91.2% of patients. An overall complication rate of 8.8% and a reoperation rate of 9.4% were recorded, respectively. Conclusions: Surgical treatment by VPS for NPH improves symptoms in most patients, when accurately selected. A standardized protocol and a multidisciplinary team dedicated to this disorder is needed to achieve an early and correct diagnosis of NPH. Follow-up with stroke volume measurement is a valuable tool for the early diagnosis of shunt malfunction or the need for valve adjustment.

Amyloid Positive Hydrocephalus: A Hydrocephalic Variant of Alzheimer's Disease?

Alzheimer's disease (AD) and normal pressure hydrocephalus (NPH) commonly coexist. We aimed to characterize an overlapping syndrome of AD and NPH that presents with gait disturbance, ventriculomegaly on magnetic resonance imaging, and significant amyloid deposition on positron emission tomography (PET). Of 114 patients who underwent cerebrospinal fluid (CSF) drainage for a possible diagnosis of NPH between 2015 and 2020 in Samsung Medical Center, we identified 24 patients (21.1%) with the NPH patients with amyloid deposition on PET, which we referred to as hydrocephalic AD in this study. We compared their clinical and imaging findings with those of 123 typical AD without hydrocephalic signs/symptoms. We also investigated the frequency and potential predictors of the tap test response in hydrocephalic AD. Evans' index was 0.36±0.03, and a disproportionately enlarged subarachnoid space was present in 54.2% of the hydrocephalic AD patients. The mean age (75.2±7.3 years) and the APOE4 frequency (68.2%) did not differ from those of AD controls. However, the hydrocephalic AD patients showed better memory and language performance, and a thinner cingulate cortex. About 42% of the hydrocephalic AD patients responded to the tap test, of whom seven underwent shunt surgery. Cognition did not improve, whereas gait improved after shunt surgery in all. Hydrocephalic AD has different neuropsychological and imaging characteristics from typical AD. Future studies are warranted to further investigate the effect of CSF removal on their clinical course and to elucidate the pathophysiological interaction between amyloid and NPH.

Programmable shunt valve affected by behind-the-ear hearing device: A case report and literature review

Background: It is known that interactions between programmable Ventriculoperitoneal Shunt (VPS) valves and electromagnetic and hearing devices may change the valve settings. We reported a patient using programmable VPS valves and hearing devices and reviewed the literature.&#x0D; Case Description: A 71-year-old man was implanted with a programmable VPS valve with the diagnosis of Normal Pressure Hydrocephalus. A hearing device (behind-the-ear) was proposed because of hearing difficulties, but it was suggested that it be discontinued because it did not help. However, the patient used it twice because of his current dementia, forgetting the doctor’s recommendations. The setting of the valve has changed in these two different times that this behind-the-ear hearing device is used. Long-term follow-ups showed no change in valve settings except those two situations.&#x0D; Conclusion: It is important to note that patients using hearing devices and programmable VPS valves are a unique group of patients. There are not enough studies showing the relationship between the behind-the-ear hearing devices and programmable VPS. It should be kept in mind that hearing devices with magnetic field strength may change the setting of the valves.

Decreased Craniocervical CSF Flow in Patients with Normal Pressure Hydrocephalus: A Pilot Study.

Normal pressure hydrocephalus is characterized by systolic peaks of raised intracranial pressure, possibly due to a reduced compliance of the spinal CSF spaces. This concept of a reduced spinal CSF buffer function may be reflected by a low cervical CSF outflow from the cranium. The aim of this study was to investigate craniospinal CSF flow rates by phase-contrast MR imaging in patients with normal pressure hydrocephalus. A total of 42 participants were included in this prospective study, consisting of 3 study groups: 1) 10 patients with normal pressure hydrocephalus (mean age, 74 [SD, 6] years, with proved normal pressure hydrocephalus according to current scientific criteria); 2) eighteen age-matched healthy controls (mean age, 71 [SD, 5] years); and 3) fourteen young healthy controls (mean age, 21 [SD, 2] years, for investigation of age-related effects). Axial phase-contrast MR imaging was performed, and the maximal systolic CSF and total arterial blood flow rates were measured at the level of the upper second cervical vertebra and compared among all study groups (2-sample unpaired t test). The maximal systolic CSF flow rate was significantly decreased in patients with normal pressure hydrocephalus compared with age-matched and young healthy controls (53 [SD, 40] mL/m; 329 [SD, 175] mL/m; 472 [SD, 194] mL/m; each P < .01), whereas there were no significant differences with regard to maximal systolic arterial blood flow (1160 [SD, 404] mL/m; 1470 [SD, 381] mL/m; 1400 [SD, 254] mL/m; each P > .05). The reduced maximal systolic craniospinal CSF flow rate in patients with normal pressure hydrocephalus may be reflective of a reduced compliance of the spinal CSF spaces and an ineffective spinal CSF buffer function. Systolic craniospinal CSF flow rates are an easily obtainable MR imaging-based measure that may support the diagnosis of normal pressure hydrocephalus.

Automated Segmentation and Connectivity Analysis for Normal Pressure Hydrocephalus.

Objective and Impact Statement. We propose an automated method of predicting Normal Pressure Hydrocephalus (NPH) from CT scans. A deep convolutional network segments regions of interest from the scans. These regions are then combined with MRI information to predict NPH. To our knowledge, this is the first method which automatically predicts NPH from CT scans and incorporates diffusion tractography information for prediction. Introduction. Due to their low cost and high versatility, CT scans are often used in NPH diagnosis. No well-defined and effective protocol currently exists for analysis of CT scans for NPH. Evans' index, an approximation of the ventricle to brain volume using one 2D image slice, has been proposed but is not robust. The proposed approach is an effective way to quantify regions of interest and offers a computational method for predicting NPH. Methods. We propose a novel method to predict NPH by combining regions of interest segmented from CT scans with connectome data to compute features which capture the impact of enlarged ventricles by excluding fiber tracts passing through these regions. The segmentation and network features are used to train a model for NPH prediction. Results. Our method outperforms the current state-of-the-art by 9 precision points and 29 recall points. Our segmentation model outperforms the current state-of-the-art in segmenting the ventricle, gray-white matter, and subarachnoid space in CT scans. Conclusion. Our experimental results demonstrate that fast and accurate volumetric segmentation of CT brain scans can help improve the NPH diagnosis process, and network properties can increase NPH prediction accuracy.

Change in Balance and Neuropsychological Measures Post-Lumbar Drain Trial in Patients with Suspected Normal Pressure Hydrocephalus

Objective: Ventriculoperitoneal (VP) shunting is commonly used to treat normal pressure hydrocephalus (NPH). Assessment of cognition and balance pre- and post-lumbar drain (LD) can be used to provide objective metrics which may help determine the potential benefit of VP shunting. The aim of this investigation was to determine which measures identify clinical change as a result of a LD trial and to develop recommendations for standard NPH clinical assessment procedures. Methods: The Berg Balance Scale (BBS) and a brief battery of commonly used neuropsychological tests pre- and post-LD (MMSE, trail making test, animal fluency, Hopkins Verbal Learning Test – Revised, and digit span) were administered to 86 patients with a diagnosis of NPH. Subjects were divided into groups based on whether or not clinical change was present, and thus, VP shunting was recommended post-LD, and predictors of group membership were examined. Results: Significant improvements (p < 0.05) were seen on the BBS and Trail Making Part B in the VP shunt-recommended group, with no other significant changes over time in either group. Regression analyses found that VP shunt recommendation was accurately predicted for 80% of the sample using the BBS score alone, with accuracy increasing to 85% when Trails B was added. Conclusions: Scores from the BBS and Trails B were most likely to change in those chosen to undergo VP shunting post-LD. Given that the typical clinical presentation of NPH includes gait disturbance and cognitive impairment, it is recommended that a standard pre-/post-LD evaluation include the BBS and trail making test.