Normal Pressure Hydrocephalus Research Articles

Gut Microbiome Changes in Patients With Idiopathic Normal Pressure Hydrocephalus.

The gut microbiome is a complex system within the human gastrointestinal tract. The bacteria play a significant role in human health, and some can promote inflammation and pathologic processes through chemical interactions or metabolites. Gut microbiome dysbiosis has been linked to some neurological and other diseases. Here we aimed to examine microbiome differences between patients with a progressive neurological disorder, idiopathic normal pressure hydrocephalus (iNPH), compared with healthy controls (CO). We recruited 37 neurologically healthy CO and 10 patients with shunted iNPH. We evaluated these participants' cognition using the CERAD-NB test battery and CDR test, and collected a variety of information, including about dietary habits and health. We also collected fecal samples, which were subjected to 16S amplicon sequencing to analyze differences in gut microbiome composition. We found that the iNPH group exhibited significantly different abundances of 10 bacterial genera compared with the CO group. The Escherichia/Shigella and Anaeromassilibacillus genera were most remarkably increased. Other increased genera were Butyrivibrio, Duncaniella, and an unidentified genus. The decreased genera were Agathobaculum, Paramuribaculum, Catenibacterium, and 2 unidentified genera. Here we report the first identified microbiome differences in iNPH patients compared with healthy controls.

Development of a Clinical Nomogram for Predicting Shunt-Dependent Hydrocephalus

Abstract Background Hydrocephalus (HCP) is one of the neurosurgical conditions that can lead to impaired quality of life, disability, and mortality. The nomogram is a clinical prediction tool that has been studied in a variety of medical conditions. Hence, the primary objective of the present study was to establish the nomogram for predicting shunt-dependent HCP in patients with varied etiologies. The secondary objective was to identify predictors associated with shunt-dependent HCP. Methods In the present study, 382 adult patients with various etiologies of HCP who had undergone ventriculostomy were included retrospectively. Several clinical factors, imaging findings, and ventricular indexes were analyzed for shunt-dependent HCP in both univariate and multivariable analysis. Based on binary logistic regression, the nomogram was created and internally validated from the final model. Results Shunt-dependent HCP was observed in 25.7% of the present cohort. Initially, progressive headache, preoperative seizure, Evans index, third ventricle index, cella media index, ventricular score, and mass diameter were candidate predictors from univariate analysis. The final model which had the lowest Akaike information criterion comprised the third ventricle index and cella media index. Therefore, the model's performance had an area under the receiver operating characteristic curve (AUC) of 0.712, Moreover, the AUCs of bootstrapping and cross-validation methods were 0.701 and 0.702, respectively. Conclusion In summary, clinical factors and ventricular measures that were strongly associated with shunt-dependent HCP were used to develop clinical prediction tools that could help physicians make decisions and care for high-risk patients in general practice.

Long-term Cognitive Outcomes of Elderly Patients After Shunt Surgery for Idiopathic Normal Pressure Hydrocephalus (iNPH): A Literature Review (P9-9.015)

Long-term Cognitive Outcomes of Elderly Patients After Shunt Surgery for Idiopathic Normal Pressure Hydrocephalus (iNPH): A Literature Review (P9-9.015)

The eShunt® System: A Novel Minimally Invasive CSF Shunting System for the Treatment of Idiopathic Normal Pressure Hydrocephalus (P10-4.014)

The eShunt® System: A Novel Minimally Invasive CSF Shunting System for the Treatment of Idiopathic Normal Pressure Hydrocephalus (P10-4.014)

Efficacy and Complications of Lumboperitoneal Shunt for Idiopathic Normal Pressure Hydrocephalus in Elderly Patients: A Systematic-review and Meta-analysis (P11-9.001)

Efficacy and Complications of Lumboperitoneal Shunt for Idiopathic Normal Pressure Hydrocephalus in Elderly Patients: A Systematic-review and Meta-analysis (P11-9.001)

The grasp reflex in patients with idiopathic normal pressure hydrocephalus.

To investigate the prevalence and intensity of grasp reflexes and to examine changes in these reflexes after shunt surgery in patients with idiopathic normal pressure hydrocephalus (iNPH). We enrolled 147 patients with probable iNPH. A standard procedure was used to determine the presence of grasp reflexes, and the intensity of these reflexes was assessed using a four-category classification. Clinical rating scales and their correlation with grasp reflexes were also evaluated. Grasp reflexes were reassessed in 72 patients 1year after surgery. We found that approximately 50.3% of patients with iNPH exhibited a positive grasp reflex. Among these patients, 69% exhibited bilateral positivity, while the remaining patients showed unilateral positivity. Furthermore, the intensity of the grasp reflex was significantly correlated with the severity of gait and with cognitive, urinary, motor, and behavioural symptoms. Surgical interventions led to a reduction (41.7%) or maintenance (30.6%) of the reflex intensity in 72.3% of iNPH patients. The changes in reflex intensity showed significant positive correlations with changes in the number of steps of the Timed Up and Go test and Trail Making Test-A scores but not with changes in total scores on the iNPH Grading Scale. This retrospective study identified grasp reflexes as a highly prevalent phenomenon in patients with iNPH. These reflexes can assist in evaluating the severity of various symptoms, including cognitive, gait, urinary, motor and emotional symptoms.

442 A Ventriculomegaly Feature Computation Pipeline to Improve the Screening of Normal Pressure Hydrocephalus on Computed Tomography

INTRODUCTION: Normal pressure hydrocephalus (NPH) commonly presents with a triad of gait disturbance, incontinence, and memory impairment. Shunt placement effectively treats symptoms; however, NPH is commonly misdiagnosed with below 20% of patients receiving a diagnosis. Given undiagnosed NPH elderly patients often present to the emergency room (ER) with falls, algorithmic identification of NPH using non-contrast CT (NCCT) may improve diagnosis rate. METHODS: NCCTs for 84 patients with NPH, 72 headache controls (HC), 97 Alzheimer’s Disease (AD) patients, and 61 post-traumatic encephalomalacia (PTE) patients were identified using Veterans Affairs Informatics and Computing Infrastructure. Image processing pipelines were developed to extract a novel feature capturing lateral ventricle eccentricity (MaxEccLV), a proxy-Splenial Angle (p-SA), the Evans indices (EI-x, y, z), Callosal angle (CA), third ventricle width (NMax-3VW), and CSF to brain volume ratio (CSF2BVR). T-tests were used to examine group differences and logistic regression to classify between NPH, AD, PTE, and HC. RESULTS: The AUC, sensitivity, and specificity for NPH versus AD+HC+PTE was 0.94, 83.0%, and 87.0% respectively. For NPH versus HC, it was 0.98, 98.8%, and 98.6% respectively. For NPH versus AD, it was 0.90, 84.5%, and 82.5% respectively. For NPH versus PTE, it was 0.95, 91.7%, and 86.9% respectively. Significant differences were seen between NPH and HC, AD, and PTE in MaxEccLV and all other features. CONCLUSIONS: The computational pipeline proposed here can identify NPH from HCs and ventriculomegaly-causing conditions using NCCT with a high sensitivity and specificity. This may help capture undiagnosed NPH patients receiving a NCCT due to presentation to the ER as a fall.

Utilizing kinematic analysis of postural instability as an objective measure to aid in distinguishing between normal pressure hydrocephalus and Parkinson's disease.

Patients with normal pressure hydrocephalus (NPH) and Parkinson's Disease (PD) can clinically appear quite similar at baseline evaluation. We sought to investigate the use of kinematic assessment of postural instability (PI) using inertial measurement units (IMUs) as a mechanism of differentiation between the two disease processes. 20 patients with NPH, 55 patients with PD, and 56 age-matched, healthy controls underwent quantitative pull test examinations while wearing IMUs at baseline. Center of mass and foot position data were used to compare velocity and acceleration profiles, pull test step length, and reaction times between groups and as a function of Unified Parkinson's disease Rating Scale Pull Test (UPDRSPT) score. Overall, the reactive postural response of NPH patients was characterized by slower reaction times and smaller steps compared to both PD patients and healthy controls. However, when patients were grouped by UPDRSPT scores, no reliable objective difference between groups was detected. At their initial evaluation, very few NPH patients demonstrate "normal" or "mild" PI as they appear to be older upon presentation compared to PD patients. As a result, kinematic assessment utilizing IMUs may not be helpful for differentiating between NPH and PD as a function of UPDRSPT score, but rather as a more fine-tuned method to define disease progression. We emphasize the need for further evaluation of incorporating objective kinematic data collection as a way to evaluate PI and improve patient outcomes.

Ventriculoperitoneal shunt placement safety in idiopathic Normal Pressure Hydrocephalus: Anticoagulated versus non-anticoagulated patients

Many patients with idiopathic normal pressure hydrocephalus (iNPH) have medical comorbidities requiring anticoagulation that could negatively impact outcomes. This study evaluated the safety of ventriculoperitoneal shunt (VPS) placement in iNPH patients on systemic anticoagulation versus those not on anticoagulation. Patients > 60 years of age with iNPH who underwent shunting between 2018 and 2022 were retrospectively reviewed. Baseline demographics, comorbidities (quantified by modified Frailty Index (mFI) and Charlson Comorbidity Index (CCI)), anticoagulant/antiplatelet agent use (other than aspirin), operative details, and complications were collected. Outcomes of interest were the occurrence of postoperative hemorrhage and overdrainage. A total of 234 patients were included in the study (mean age 75.22 ± 6.04 years; 66.7% male); 36 were on anticoagulation/antiplatelet therapy (excluding aspirin). This included 6 on Warfarin, 19 on direct Xa inhibitors, 10 on Clopidogrel, and one on both Clopidogrel and Warfarin. Notably, 70% of patients (164/234) used aspirin alone or combined with anticoagulation or clopidogrel. Baseline mFI was similar between groups, but those on anticoagulant/antiplatelet therapy had a higher mean CCI (2.67±1.87 vs. 1.75±1.84; p=0.001). Patients on anticoagulants were more likely to experience tract hemorrhage (11.1 vs. 2.5%; p=0.03), with no significant difference in the rates of intraventricular hemorrhage or overdrainage related subdural fluid collection. Anticoagulant and antiplatelet agents are common in the iNPH population, and patients on these agents experienced higher rates of tract hemorrhage following VPS placement; however, overall hemorrhagic complication rates were similar.

Predicting post-surgical outcomes in idiopathic normal pressure hydrocephalus using clinically important changes from the cerebrospinal fluid tap test

ObjectivePatients diagnosed with idiopathic Normal Pressure Hydrocephalus (iNPH) typically experience symptom improvements after undergoing a cerebrospinal fluid-tap test (CSF-TT), These improvements are recognized as indicative of potential improvements following surgical intervention. As gait disturbance is the most common iNPH symptom, gait improvements are of predominant interest. The purpose of this study was to examine if clinically important changes in gait and balance from CSF-TT predict meaningful changes following surgery. MethodThe study involved analysis of data collected in a prospective observational study for 34 iNPH patients who underwent a CSF-TT and subsequent surgery. Linear regression, logistic regression and classification trees were used for predictive modelling comparing changes from CSF-TT with post-surgical changes in Tinetti, Timed Up and Go (TUG) and Berg Balance Scale (BBS) outcomes. ResultsPredictive models for minimal clinically important differences (MCIDs) from CSF-TT to surgery were significant for Tinetti (odds ratio = 1.42, p = 0.02) and BBS (odds ratio = 1.57, p < 0.01). Four items on Tinetti and two items on BBS were identified with a predictive accuracy of 79% and 76% respectively. BBS has the highest sensitivity (85%) and negative predictive value (77%). TUG had a 100% specificity and 100% positive predictive value. The predictive model using MCIDs for TUG was not significant (odds ratio = 1.13, p = 0.06). ConclusionClinically important changes from CSF-TT are useful in predicting post-surgical outcomes in iNPH patients. Tinetti and BBS, both have predictive value using MCID scores as cut off values, of which BBS is a stronger outcome measure for prediction.

157 Minimally Invasive Treatment of Idiopathic Normal Pressure Hydrocephalus Using the Endovascular eShunt Implant

INTRODUCTION: Idiopathic Normal Pressure Hydrocephalus (NPH) is a reversible form of dementia typically treated with ventriculo-peritoneal shunt surgery. Recently we have described the first percutaneous transfemoral transvenous deployment of an endovascular CSF shunt (eShunt® System; CereVasc, Inc., Auburndale, MA, USA) to treat communicating hydrocephalus. METHODS: Patients were included after demonstrating &gt;20% gait improvement in lumbar drainage trial. Gait was assessed using Timed Up &amp; Go (TUG) test, cognition using Montreal cognitive assessment (MoCA), and urinary incontinence using Neurogenic Bladder Symptom Score (NBSS). Results were normalized per-patient to pre-treatment scores. A composite outcome score (COS) incorporating TUG/MOCA/NBSS was computed. RESULTS: Eleven patients (4 female; mean age 74.8 ± 4.2 years) underwent successful eShunt placement. Follow-up data showed significant improvement in gait by 35.4% at 30-days (n = 6, P &lt; 0.003), 24.8% at 90-days (n = 6, p &lt; 0.03) and by 32.8% at 180-days (n = 4, p &lt; 0.01) compared to baseline. MOCA and NBSS showed significant improvements at 30-days and the COS was significantly improved at all time points (p &lt; 0.005 at 30-, 90- and 180-days). No procedural/delayed hemorrhage or unexpected readmissions were encountered during this early follow-up phase. CONCLUSIONS: In elderly patients affected by NPH and its insidious effect on mobility, cognition and urinary continence, these results show that the endovascular eShunt implant can be safely deployed with a favorable risk profile and with rapid and sustained improvements in functional outcome scores.

The role of cytokines and chemokines in the maintenance of chronic pain-a pilot study.

The immune system is believed to be important in the initiation and maintenance of chronic pain. The aim was to investigate whether patients with chronic painful polyneuropathy (PP) differ in cytokine profiles of serum and/or cerebrospinal fluid (CSF) compared with pain-free controls. Thirty-nine patients (16 women and 23 men, mean age, 69.2 ± 12.7 years, range 41-92 years) with PP (mean duration 43 ± 48.3 months) were phenotyped with quantitative sensory testing and electroneurography, and serum and CSF samples were analyzed by 40-multiplexed, bead-based cytokine immunoassays. Results were compared with 36 age- and gender-matched patients with normal pressure hydrocephalus and absence of abnormal CSF findings. Compared with controls, patients with PP had lower concentrations of several proinflammatory and anti-inflammatory chemokines and cytokines in CSF, and others showed the same tendency, among these were tumor necrosis factor-α (14.1 ± 10.0 vs 23.9 ± 16.4 pg/mL, P < 0.005), interleukin (IL)-2 (0.6 ± 0.4 vs 1.2 ± 0.6 pg/mL, P < 0.0001), IL-6 (4.7 ± 6.8 vs 7.3 ± 9 pg/mL, P = 0.001), and IL-10 (7.5 ± 6.8 vs 16.8 ± 19.2 pg/mL, P < 0.01), whereas no differences were observed in serum. Results suggest that (1) inflammatory mediators play a minor role in the maintenance of chronic pain in contrast to initiation of acute pain, (2) chemokines/cytokines are downregulated in chronic pain, or (3) chemokines/cytokines have a protective role for nerve regeneration that is disturbed in patients with chronic pain.

Frequency of brain ventricular enlargement among patients with diabetes mellitus

AimsTo determine the prevalence of dilated ventricles and concomitant high blood glucose measures. MethodsWe retrieved blood glucose measures from the emergency department database and selected a subgroup of individuals having both the radiological marker Evans’ index (EI) values and blood glucose measures. ResultsOut of 1221 consecutive patients submitted to axial Computed Tomography scans, a blood glucose measure was detected in 841 individuals. 176 scans (21 %) showed an EI > 0.30. According to the blood glucose categorization, diabetic patients were 104 (12 %), 25 of them (24 %) were dilated (mean EI 0.33). The age difference between dilated and not-dilated ventricles is about ten years in not-diabetic participants, whereas it is five years in diabetic participants. The age difference between dilated and not-dilated ventricles is about 10 years in diabetic men, whereas it zero in diabetic women. ConclusionsPathological ventricular enlargement is more frequent in men and in the elderly. In diabetic patients (especially women), the cerebral ventricles enlarge faster than in non-diabetic individuals. Age, sex, and diabetes may interact in determining how cerebral ventricle size changes over time, especially in diabetic women, making routine brain imaging advisable in these patients after the age of 70 years.

Structural neuroimaging markers of normal pressure hydrocephalus versus Alzheimer's dementia and Parkinson's disease, and hydrocephalus versus atrophy in chronic TBI-a narrative review.

Normal Pressure Hydrocephalus (NPH) is a prominent type of reversible dementia that may be treated with shunt surgery, and it is crucial to differentiate it from irreversible degeneration caused by its symptomatic mimics like Alzheimer's Dementia (AD) and Parkinson's Disease (PD). Similarly, it is important to distinguish between (normal pressure) hydrocephalus and irreversible atrophy/degeneration which are among the chronic effects of Traumatic Brain Injury (cTBI), as the former may be reversed through shunt placement. The purpose of this review is to elucidate the structural imaging markers which may be foundational to the development of accurate, noninvasive, and accessible solutions to this problem. By searching the PubMed database for keywords related to NPH, AD, PD, and cTBI, we reviewed studies that examined the (1) distinct neuroanatomical markers of degeneration in NPH versus AD and PD, and atrophy versus hydrocephalus in cTBI and (2) computational methods for their (semi-) automatic assessment on Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) scans. Structural markers of NPH and those that can distinguish it from AD have been well studied, but only a few studies have explored its structural distinction between PD. The structural implications of cTBI over time have been studied. But neuroanatomical markers that can predict shunt response in patients with either symptomatic idiopathic NPH or post-traumatic hydrocephalus have not been reliably established. MRI-based markers dominate this field of investigation as compared to CT, which is also reflected in the disproportionate number of MRI-based computational methods for their automatic assessment. Along with an up-to-date literature review on the structural neurodegeneration due to NPH versus AD/PD, and hydrocephalus versus atrophy in cTBI, this article sheds light on the potential of structural imaging markers as (differential) diagnostic aids for the timely recognition of patients with reversible (normal pressure) hydrocephalus, and opportunities to develop computational tools for their objective assessment.

A rare cause of dizziness: Hakim-Adams syndrome

It was first reported in 1965 by Hakim, Adams et al. the term normal pressure hydrocephalus (NPH) was defined by. Because of this definition, it was recorded in the literature as Hakim-Adams syndrome. A 32-year-old male patient was admitted to the green area of our emergency department with a complaint of dizziness. In the physical examination of the patient, no pathological findings were found other than mild ataxia. The brain computed tomography (CT) report revealed that the 3rd ventricle and lateral ventricles were dilated and there was a space-occupying lesion at the 4th ventricle level. The earliest sign of normal pressure hydrocephalus (NPH) is no impairment in walking. It usually manifests itself in older ages. Thanks to the anamnesis and physical examination taken in the emergency departmant and the skeptical approach, further examination was requested for the patient.

Automatic assessment of disproportionately enlarged subarachnoid-space hydrocephalus from 3D MRI using two deep learning models.

Disproportionately enlarged subarachnoid-space hydrocephalus (DESH) is a key feature for Hakim disease (idiopathic normal pressure hydrocephalus: iNPH), but subjectively evaluated. To develop automatic quantitative assessment of DESH with automatic segmentation using combined deep learning models. This study included 180 participants (42 Hakim patients, 138 healthy volunteers; 78 males, 102 females). Overall, 159 three-dimensional (3D) T1-weighted and 180 T2-weighted MRIs were included. As a semantic segmentation, 3D MRIs were automatically segmented in the total ventricles, total subarachnoid space (SAS), high-convexity SAS, and Sylvian fissure and basal cistern on the 3D U-Net model. As an image classification, DESH, ventricular dilatation (VD), tightened sulci in the high convexities (THC), and Sylvian fissure dilatation (SFD) were automatically assessed on the multimodal convolutional neural network (CNN) model. For both deep learning models, 110 T1- and 130 T2-weighted MRIs were used for training, 30 T1- and 30 T2-weighted MRIs for internal validation, and the remaining 19 T1- and 20 T2-weighted MRIs for external validation. Dice score was calculated as (overlapping area) × 2/total area. Automatic region extraction from 3D T1- and T2-weighted MRI was accurate for the total ventricles (mean Dice scores: 0.85 and 0.83), Sylvian fissure and basal cistern (0.70 and 0.69), and high-convexity SAS (0.68 and 0.60), respectively. Automatic determination of DESH, VD, THC, and SFD from the segmented regions on the multimodal CNN model was sufficiently reliable; all of the mean softmax probability scores were exceeded by 0.95. All of the areas under the receiver-operating characteristic curves of the DESH, Venthi, and Sylhi indexes calculated by the segmented regions for detecting DESH were exceeded by 0.97. Using 3D U-Net and a multimodal CNN, DESH was automatically detected with automatically segmented regions from 3D MRIs. Our developed diagnostic support tool can improve the precision of Hakim disease (iNPH) diagnosis.

Lumboperitoneal shunt and ventriculoperitoneal shunt for chronic hydrocephalus after aneurysmal subarachnoid hemorrhage: a comparison.

Chronic hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH) results in poor neurological outcomes and cognitive deficits. Currently, the main treatments for chronic hydrocephalus include ventriculoperitoneal shunt (VPS) and lumboperitoneal shunt (LPS); however, the optimal treatment for chronic hydrocephalus after aSAH remains controversial. The records of 82 patients were retrospectively analyzed, and the patients were divided into VPS and LPS groups based on surgical methods. The efficacy, shunt successful rate and complications were compared. The assessments of treatment efficacy included the Evans index score (EIS), Keifer's hydrocephalus score (KHS), Mini-Mental State Examination (MMSE) score and functional independence measure (FIM). Patients were followed up for three months to observe the postoperative curative effects and complications. The rate of shunt obstruction was significantly higher in the LPS group than that in the VPS group (p < 0.05), and the shunt successful rate was significantly higher in the VPS group than that in the LPS group (p < 0.05). The total rate of complications was 24.4% for LPS and 39% for VPS. The improvements in EIS, KHS, MMSE, and FIM within each group after the shunt were significantly different compared to those before shunt (p < 0.05). Compared to those in the LPS group, the improvements in EIS, KHS, MMSE, and FIM were significantly different in the VPS group after shunt (p < 0.05). Compared with LPS, VPS in the treatment for chronic hydrocephalus after aSAH had greater therapeutic efficacy, as indicated by improved radiological outcomes, improved shunt successful rate, improved clinical outcomes, and improved quality of life. Therefore, we believe that VPS is the preferred treatment option for chronic hydrocephalus after aSAH, while LPS should only be used as an alternative to VPS.

Potential Role of Gut Microbiota in Development of Idiopathic Normal Pressure Hydrocephalus: A Matter or Coincidence?

Potential Role of Gut Microbiota in Development of Idiopathic Normal Pressure Hydrocephalus: A Matter or Coincidence?

Freezing of gait in idiopathic normal pressure hydrocephalus

BackgroundReports of freezing of gait (FoG) in idiopathic normal pressure hydrocephalus (iNPH) are few and results are variable. This study’s objective was to evaluate the frequency of FoG in a large cohort of iNPH patients, identify FoG-associated factors, and assess FoG’s responsiveness to shunt surgery.MethodsVideotaped standardized gait protocols with iNPH patients pre- and post-shunt surgery (n = 139; median age 75 (71–79) years; 48 women) were evaluated for FoG episodes by two observers (Cohens kappa = 0.9, p < 0.001). FoG episodes were categorized. Mini-mental state examination (MMSE) and MRI white matter hyperintensities (WMH) assessment using the Fazekas scale were performed. CSF was analyzed for Beta-amyloid, Tau, and Phospho-tau. Patients with and without FoG were compared.ResultsTwenty-two patients (16%) displayed FoG at baseline, decreasing to seven (8%) after CSF shunt surgery (p = 0.039). The symptom was most frequently exhibited during turning (n = 16, 73%). Patients displaying FoG were older (77.5 vs. 74.6 years; p = 0.029), had a slower walking speed (0.59 vs. 0.89 m/s; p < 0.001), a lower Tinetti POMA score (6.8 vs. 10.8; p < 0.001), lower MMSE score (21.3 vs. 24.0; p = 0.031), and longer disease duration (4.2 vs. 2.3 years; p < 0.001) compared to patients not displaying FoG. WMH or CSF biomarkers did not differ between the groups.ConclusionsFoG is occurring frequently in iNPH patients and may be considered a typical feature of iNPH. FoG in iNPH was associated with higher age, longer disease duration, worse cognitive function, and a more unstable gait. Shunt surgery seems to improve the symptom.

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.