The impact of cerebrospinal fluid shunting on quality of life in idiopathic normal pressure hydrocephalus: a long-term analysis.

OBJECTIVE: Idiopathic normal pressure hydrocephalus (iNPH) represents an insidious type of dementia considered reversible after shunt placement. Although the clinical outcome has been widely studied, few studies have reported on quality of life (QOL) after surgery. This study evaluated the long-term clinical and QOL outcomes of iNPH patients after ventriculoperitoneal shunt (VPS) implantation. Factors influencing QOL in iNPH were also investigated. METHODS: From 2009 to 2020, a single-institution retrospective study was conducted to compare shunted iNPH patients with a homogeneous control group. QOL was analyzed using the SF-36 questionnaire with yearly follow-up for as long as 11 years. Severity of symptoms, comorbidities, and clinical data were also recorded. RESULTS: Among 187 treated patients, 15 had died at the time of the authors' evaluation, and 45 did not match the inclusion criteria. The mean ± SD (range) follow-up was 118.5 ± 4.2 (18-132) months. QOL improved in 103/130 (79%) patients through 5 years after shunt surgery, although it remained lower than that of the control group (p < 0.0001). The SF-36 score reduced progressively, reaching baseline at 5-7 years of follow-up and decreased to below baseline at 7-11 years of follow-up (p < 0.0001). Predictors of improved QOL were younger age (p < 0.001), lower body mass index (BMI) (p < 0.001), and better Mini-Mental State Examination (MMSE) performance (p < 0.001) before surgery. Decreased postoperative QOL was associated with cerebrovascular disease, diabetes, and severity of symptoms (gait and cognition) at presentation (p < 0.001). CONCLUSIONS: VPS implantation, along with a strict and comprehensive follow-up, has been shown to improve QOL in iNPH patients for as long as 5 years after surgery. Younger age, lower BMI, and better MMSE score are positive predictors of improved QOL after shunt placement.

A case of primary central nervous system lymphoma presenting as a shunt complication.

The authors describe an 82-year-old female with a right frontal ventriculoperitoneal (VP) shunt for long-standing normal pressure hydrocephalus (NPH) who presented with worsening incontinence and gait instability. She was found to have right lateral ventricle collapse around the shunt catheter and subsequently underwent shunt revision, which failed to improve her symptoms. Magnetic resonance imaging (MRI) was obtained on postoperative day two, which demonstrated a ventricular lesion. Endoscopic brain biopsy was performed and a diagnosis of primary central nervous system lymphoma (PCNSL) was made. The authors believe this is the first published case of PCNSL presenting as a VP shunt complication in a patient with NPH.

Spinal paraganglioma presenting as normal pressure hydrocephalus: a rare occurrence.

Objective: We report a 63 years old female who presented with confusion, urinary retention and gait disturbances.Method: CT head shows communicating hydrocephalus. Spinal MRI demonstrated an L5- S1 intradural lesion.Result: Histopathology proved it to be paraganglioma. Postoperative CT head showed reduction in size of ventricles. Association between spinal tumors and hydrocephalus is known but occurs infrequently.Conclusion: The presence of an intraspinal tumor must be kept in mind as a possible cause of the hydrocephalus.

Undiagnosed Cryptococcus gattii meningitis leading to subsequent ventriculoperitoneal shunt infection in a patient with symptoms of normal pressure hydrocephalus: case report and literature review.

BACKGROUND: Cryptococcus gattii is known to be an etiologic agent of human cryptococcosis, particularly in immunocompetent persons. C. gattii infection usually involves the central nervous system, the respiratory tract, or may be disseminated. Here we report an atypical manifestation of C. gattii infection in a patient who had C. gattii meningitis complicating the ventriculoperitoneal (VP) shunt infection and concurrent infected intraabdominal VP shunt pseudocyst. CASE PRESENTATION: A 66-year-old Thai female was initially diagnosed with normal pressure hydrocephalus (NPH) and underwent programmable VP shunt placement. However, she still suffered from recurrent communicating hydrocephalus with in-place VP shunt, and later developed recurrent gait impairment, chronic abdominal pain and abdominal mass. Radiological studies demonstrated recurrent hydrocephalus and a very large intraabdominal VP shunt pseudocyst. C. gattii was isolated from both the cerebrospinal fluid and the pseudocyst aspiration. C. gattii meningitis complicating the VP shunt infection and concurrent infected intraabdominal VP shunt pseudocyst was diagnosed. Prolonged antifungal therapy, removal of the infected VP shunt with subsequent implant of a new shunt provided a good outcome. CONCLUSION: Chronic C. gattii meningitis should be aware in a patient presenting with normal pressure hydrocephalus. Under-diagnosed cryptococcal meningitis following VP shunt insertion for treating the hydrocephalus can render a complicated VP shunt infection including infected VP shunt pseudocyst.

A case of idiopathic normal pressure hydrocephalus in an elder diabetic patient.

The clinical entity idiopathic normal pressure hydrocephalus (iNPH) is characterized by dementia, urinary incontinence, gait ataxia. An 80-year old man with a past history of Type 2 diabetes mellitus admitted to our hospital. Combination of twice Aspart and Aspart premixed30/70 insulin were used. Although, he was unable to inject insulin by himself recently. On physical examination, he walked in a mildly wide based manner. According to his family, urinary incontinence was existed. Laboratory data were as follows: Postrandial blood glucose 243 mg/dl and glycated hemoglobin 8.0% (NGSP). Brain magnetic resonance imaging (MRI) scans showed thinning of the corpus callosum with enlargement of the lateral ventricles on a colonal image. Evan's ratio was 0.29. The revised version of Hasegawa's Dementia scale (HDS-R) was 10. The patient showed no evidence a related antecedent event, such as head trauma, intracerebral hemorrhage and meningitis. Thus, he was diagnosed as having possible Idiopathic normal pressure hydrocephalus (iNPH). The following several psychological tests and walking test were applied. Before and after the tap, he was evaluated using the HDS-R, Mini mental state examination (MMSE), Timed Up and Go test (TUG). Insulin was replaced by glargine, and Sitagliptin was added. On the 31 day, the patient underwent Ventriculo-perioneal shunt. Laboratoly data and memory impairment were also improved. 8 month's later, HbA1c was 7.5%. iNPH occurs in the elderly and is characterized by a clinical triad of gait disturbance, urinary incontinence and dementia. In the present case, thinning of the corpus callosum with enlargement of the lateral ventricles was detected by MRI. 49% of iNPH patients had Diabetes mellitus. However, we were unable to detect a relationship iNPH and Diabetes mellitus. Cognitive impairment may interfere with the insulin therapy. In the present case, failure of insulin self-injection was the first clinical sign to appear. We were able to reduce dose of insulin. We conclude that iNPH is a treatable disorder, especially when treatment is started early in the course of the disease.

Neurological symptoms in a patient with isolated adrenocorticotropin deficiency: case report and literature review.

BACKGROUND: Isolated adrenocorticotropic hormone (ACTH) deficiency is a pituitary disorder characterized by reduction only in the secretion of ACTH. Although the underlying mechanism remains to be elucidated, numbers of cases with this entity have been increasing. We experienced a case presenting with gait disturbance necessitating differential diagnosis from idiopathic normal pressure hydrocephalus (iNPH). CASE PRESENTATION: A 69-year-old female with a complaint of difficulty walking and suspected to have iNPH at a prior hospital was referred to our department. For the prior three years, she had suffered from a progressive gait disturbance. Magnetic resonance imaging (MRI) revealed global ventricular dilatation. The typical features of the gait in iNPH cases were all identifiable. Neuropsychological dementia scale tests showed deterioration. However, the major feature of a disproportionately enlarged subarachnoid-space on MRI was not obvious. The patient developed progressively worsening fatigue during hospitalization. Her symptoms resembled those of hypothalamic-pituitary tumor patients. Serum ACTH and cortisol levels were low. While corticotrophin releasing hormone stress tests showed no response, other stress tests using thyrotropin releasing hormone, luteinizing hormone releasing hormone, and growth hormone releasing hormone yielded normal responses, indicating a diagnosis of isolated ACTH deficiency. We initiated corticosteroid therapy, and her gait disturbance improved promptly. CONCLUSION: Isolated ACTH deficiency may have major significance to the differential diagnosis of iNPH. Early consideration of this entity is anticipated to facilitate making an early diagnosis.

Revisiting secondary normal pressure hydrocephalus: does it exist? A review.

OBJECTIVE There are several etiologies that can lead to the development of secondary normal pressure hydrocephalus (sNPH). The aim of this study was to evaluate the etiology, diagnosis, treatment, and outcome in patients with sNPH and to highlight important differences between the separate etiologies. METHODS A comprehensive review of the literature was performed to identify studies conducted between 1965 and 2015 that included data regarding the etiology, treatment, diagnosis, and outcome in patients with sNPH. Sixty-four studies with a total of 1309 patients were included. The inclusion criteria of this study were articles that were written in English, included more than 2 patients with the diagnosis of sNPH, and contained data regarding the etiology, diagnosis, treatment, or outcome of NPH. The most common assessment of clinical improvement was based on the Stein and Langfitt grading scale or equivalent improvement on other alternative ordinal grading scales. RESULTS The main etiologies of sNPH were subarachnoid hemorrhage (SAH) in 46.5%, head trauma in 29%, intracranial malignancies in 6.2%, meningoencephalitis in 5%, and cerebrovascular disease in 4.5% of patients. In 71.9% of patients the sNPH was treated with ventriculoperitoneal shunt placement, and 24.4% had placement of a ventriculoatrial shunt. Clinical improvement after shunt placement was reported in 74.4% and excellent clinical improvement in 58% of patients with sNPH. The mean follow-up period after shunt placement was 13 months. Improvement was seen in 84.2% of patients with SAH, 83% of patients with head trauma, 86.4% of patients with brain tumors, 75% of patients with meningoencephalitis, and 64.7% of patients with NPH secondary to stroke. CONCLUSIONS Secondary NPH encompasses a diverse group of clinical manifestations associated with a subset of patients with acquired hydrocephalus. The most common etiologies of sNPH include SAH and traumatic brain injury. Secondary NPH does indeed exist, and should be differentiated from idiopathic NPH based on outcome and on clinical, pathophysiological, and epidemiological characteristics, but should not be considered as a separate entity.

Cerebrospinal fluid disturbance in overweight women after occipitocervical decompression in Chiari malformation type I.

BACKGROUND: Cerebrospinal fluid disturbance (CSFD) is a well-known complication after occipitocervical decompression (OCD) in patients with Chiari malformation type I (CMI). There is scarce data focusing on preoperative patients' factors predisposing to development of CSF disturbance. The aim of this study is to evaluate a prognostic value of some patients' factors in the prediction of CSFD after OCD in CMI patients. MATERIALS AND METHODS: We undertook a 10-year (2003-2013) retrospective study of all OCD in patients with CMI performed at Sahlgrenska IC, Sahlgrenska University Hospital, Sweden. A total of 52 consecutive patients were obtained from the operation database and we excluded one patient who was previously diagnosed with normal-pressure hydrocephalus. Data regarding preoperative age, body mass index, gender, degree of tonsillar herniation and syrinx were registered. Development of CSFD after OCD was noted. RESULTS: Of the 51 patients reviewed, six had CSFD after OCD and were managed using a form of CSF diversion procedure. All of the patients who developed CSFD were females. They had a mean body mass index of 32.3 compared to a mean of 24.3 in patients without CSFD (p = 0.0011). There was no difference between the two groups with regard to the other examined patient factors. CONCLUSIONS: CSF diversion was needed in six consecutive adult Chiari malformation type I patients who underwent occipitocervical decompression. All patients with postoperative CSFD were female and their mean BMI was significantly higher than patients without this complication.

[Normal pressure hydrocephalus]. / Normaldruckhydrozephalus.

CLINICAL ISSUE: Normal pressure hydrocephalus (NPH) is a disorder found mainly in the elderly (> 60 years) with an increasing prevalence with age and is one of the few treatable causes of dementia. If untreated NPH often leads to severe motor, psychomotor and irreversible cognitive deficits. The pathogenesis is not yet fully understood. Clinical symptoms consist of the (not always complete) classical triad of equilibrium and gait disturbances followed later by incontinence and dementia. Symptoms often show a gradual progression to irreversibility in non-treated patients; therefore, early diagnosis and treatment are mandatory. Important differential diagnoses are Parkinson's disease (similar gait), Alzheimer's disease and vascular dementia, not least due to the high comorbidity of these conditions with NPH. STANDARD RADIOLOGICAL METHODS: The standard radiological method for evaluation of NPH is conventional cross-sectional imaging that typically shows ventriculomegaly (Evans' index > 0.3 and cella media index < 4) often combined with the so-called disproportionately enlarged subarachnoid space hydrocephalus (DESH) pattern (tight convexity sulci and enlarged sylvian fissure). These findings should be differentiated from ventriculomegaly in atrophy combined with enlarged convexity sulci. METHODICAL INNOVATIONS: Special magnetic resonance imaging (MRI) techniques can be used to evaluate cerebrospinal fluid (CSF) flow but are not yet part of the diagnostic guidelines. ACHIEVEMENTS/PRACTICAL RECOMMENDATIONS: Combined with cross-sectional imaging, well-established clinical and invasive diagnostic tests, such as repeated spinal tap or lumbar drainage with re-evaluation of clinical symptoms lead to a diagnosis and help with preoperative patient selection for CSF diversion. Ventriculoperitoneal CSF shunting has proven to be safe and is the only known successful therapy for NPH.

Primary leptomeningeal B-cell lymphoma with normal pressure hydrocephalus at diagnosis.

An 80-year-old man, presenting with gait disturbance and memory loss, had findings of normal pressure hydrocephalus. Primary leptomeningeal lymphoma (PLML) was diagnosed based on cytology and flow cytometry of cerebrospinal fluid obtained by examination. Gadolinium-enhanced MRI showed enhancement of the brain and spinal cord but FDG-PET/CT revealed no lymph node swelling. With intrathecal chemotherapy, meningeal lesions disappeared and the gait disturbance and memory loss improved. However, the disease recurred three months later, manifesting as left facial nerve palsy, but the symptoms disappeared in response to intrathecal chemotherapy and systemic rituximab administration. Although a tumor lesion in the spinal canal was suggested by MRI examination, the patient has maintained a good clinical course for four years with intrathecal chemotherapy every three months. PLML is a very rare disease and its diagnosis is difficult. Repeated intrathecal chemotherapy appeared to be effective against PLML in this case.

Normal pressure hydrocephalus as a failure of ICP homeostasis mechanism: the hidden role of Monro-Kellie doctrine in the genesis of NPH.

OBJECTIVE: The theme of this paper is to outline that the genesis of normal pressure hydrocephalus (NPH) is governed by the intracranial pressure (ICP) homeostatic principle. The development of this new concept is based mainly on rethinking the well-known Monro-Kellie doctrine in the way that ICP homeostasis mechanism is not only a mechanism that works to prevent pathologically high ICP but also a mechanism that aims to protect from pathologically low ICP. METHODS: The NPH-related literatures are reviewed and reinterpreted to generate a new paradigm for the cascade of pathophysiological events that leads to the genesis NPH, as well as the mechanism of clinical beneficial effects and complications of the shunting procedure. RESULTS: According to this new paradigm, the suboptimal cerebral perfusion that is associated with the impairment of the cerebral autoregulation is the initial step in the genesis of NPH. When the overall volume of blood that circulates intracranially is diminished, a chronic low ICP with episodes of pathologically low ICP occurs. Since the cranial vault is not collapsible, those episodes of low ICP are compensated by the accumulation of cerebrospinal fluid (CSF) to keep the ICP in normal ideal range. The impairment of brain toxin-flushing mechanism because of CSF pooling combined with the already-established suboptimal cerebral perfusion leads to functional disinhibition of the cerebral cortex. CONCLUSION: Recognizing the importance of ICP homeostatic mechanisms in the genesis of the NPH is a simple yet novel view that could change the way we look at NP and can give a basic and fundamental theoretical frame work to achieve better understanding of NPH.

[Symptomatology of Idiopathic Normal Pressure Hydrocephalus].

Idiopathic normal pressure hydrocephalus causes a triad of gait disturbance, dementia, and urinary incontinence in the elderly. All these symptoms may manifest as age-related functional decline or from neurological and non-neurological diseases common in the elderly. In idiopathic normal pressure hydrocephalus, characterized by ataxic-ataxic gait, subcortical dementia, and urge urinary incontinence, it is clinically important to consider these characteristic features. This overview describes the symptomatology of idiopathic normal pressure hydrocephalus.

Normal pressure hydrocephalus in the spectrum of neurological complications of systemic lupus erythematosus.

Normal pressure hydrocephalus is an unusual manifestation of systemic lupus erythematosus and its pathogenesis is still unclear. We report the case of a 39-year-old white woman with systemic lupus erythematosus who developed magnetic gait, speech difficulties, progressive memory impairment, urinary incontinence and episodes of involuntary closure of the eyelids. Signs and symptoms, associated with ventriculomegaly and normal cerebrospinal fluid pressure, suggested normal pressure hydrocephalus, which as a complication of systemic lupus erythematosus believably develops due to the insidious inflammatory process that occurs in the meningeal tissues or to the vasculitis itself. Normal pressure hydrocephalus tends to develop secondary to trauma, infection or subarachnoid haemorrhage, but in 50 % of patients no aetiology is found. Shunt surgery is the only effective treatment, specifically for the gait disorder, which usually improves more than the cognitive symptoms. Since the tap-test showed a strongly positive result, a medium pressure ventriculoperitoneal shunt was inserted, further replaced by a high pressure one in view of the complications, with less than expected improvement. Subdural hematomas and empyemas developed, requiring surgery and antibiotic therapy. A new tap-test was positive, and the patient improved only after a programmable valve was finally placed. However, pressure regulation shall be continuously required, and shunt dysfunction might still develop in the long term. The few similar case reports in the literature are reviewed, confirming the rarity of this neurological complication of systemic lupus erythematosus.

Hospital Frailty Risk Score Predicts Adverse Events and Readmission Following a Ventriculoperitoneal Shunt Surgery for Normal Pressure Hydrocephalus.

OBJECTIVE: The aim of this study was to evaluate the impact of a Hospital Frailty Risk Score (HFRS) on unplanned readmission and health care resource utilization in normal pressure hydrocephalus (NPH) patients undergoing a ventriculoperitoneal (VP) shunt surgery. METHODS: A retrospective cohort study was performed using the 2016-2019 Nationwide Readmission Database. All NPH patients (≥60 years) undergoing a VP shunt surgery were identified using ICD-10-CM diagnostic and procedural codes. Patients were dichotomized into 2 cohorts as follows: Low HFRS (<5) and Intermediate-High HFRS (≥5). A multivariate logistic regression analysis was then used to identify independent predictors of adverse event (AE) and 30- and 90-day readmission. RESULTS: Of 13,262 patients, 4386 (33.1%) had an Intermediate-High HFRS score. A greater proportion of the Intermediate-High HFRS cohort experienced at least one AE (1.9 vs. 22.1, P < 0.001). The Intermediate-High HFRS cohort also had a longer length of stay (2.3 ± 2.4 days vs. 7.0 ± 7.7 days, P < 0.001), higher non-routine discharge rate (19.9% vs. 39.9%, P < 0.001), and greater admission cost ($14,634 ± 5703 vs. $21,749 ± 15,234, P < 0.001). The Intermediate-High HFRS cohort had higher rates of 30- (7.6% vs. 11.0%, P < 0.001) and 90-day (6.8% vs. 8.3%, P < 0.001) readmissions. On a multivariate regression analysis, Intermediate-High HFRS compared to Low HFRS was an independent predictor of any AE (odds ratio, 16.6; 95% confidence interval, [12.9-21.5]; P < 0.001) and 30-day readmission (odds ratio, 1.4; 95% confidence interval, [1.2-1.7]; P < 0.001). CONCLUSIONS: Our study suggests that frailty, as defined by HFRS, is associated with increased resource utilization in NPH patients undergoing VP shunt surgery. Furthermore, HFRS was an independent predictor of adverse events and 30-day hospital readmission.

Lumboperitoneal Shunt Surgery under Spinal Anesthesia on Idiopathic Normal Pressure Hydrocephalus Patients.

Since the publication of guidelines for managing idiopathic normal pressure hydrocephalus (iNPH) in 2004, an increasing number of patients with iNPH have been undergoing shunt surgery in Japan. However, shunt surgeries for iNPH can be challenging because the procedures are performed on elderly patients. General anesthesia-related risks, such as postoperative pneumonia or delirium, are higher in the elderly. To decrease these risks, we applied spinal anesthesia on a lumboperitoneal shunt (LPS). Herein, we analyzed our methods focusing on the postoperative outcomes. We retrospectively analyzed 79 patients who underwent LPS at our institution with more than one year of follow-up. The patients were divided into two groups based on the anesthetic approach, that is, 1) general anesthesia and 2) spinal anesthesia, and were examined in terms of postoperative complications, delirium, and postoperative hospital stay. In the general anesthesia group, two patients had respiratory complications after the surgery. The postoperative delirium score using the intensive care delirium screening checklist (ICDSC) was 0 (2) (median [interquartile range]), and the length of postoperative hospital stay was 11 (4) days. In the spinal anesthesia group, no patients had respiratory complications. The postoperative mean ICDSC was 0 (1), and the length of postoperative hospital stay was 10 (3) days. Although there was no significant difference regarding postoperative delirium existed, LPS under spinal anesthesia decreased respiratory complications and significantly shortened the postoperative hospital stay. LPS under spinal anesthesia could be an alternative to general anesthesia in elderly patients with iNPH and possibly lessen the general anesthesia-related risks.

Comparison of cerebrospinal fluid biomarkers between idiopathic normal pressure hydrocephalus and subarachnoid hemorrhage-induced chronic hydrocephalus: a pilot study.

BACKGROUND: We examined the cerebrospinal fluid (CSF) markers of subarachnoid hemorrhage (SAH)-induced and idiopathic normal pressure hydrocephalus (INPH) to investigate the pathophysiology and mechanism of communicating hydrocephalus compared to obstructive hydrocephalus. MATERIAL/METHODS: We obtained CSF samples from 8 INPH, 10 SAH-induced hydrocephalus, and 6 unmatched patients with non-hemorrhagic obstructive hydrocephalus during their ventriculoperitoneal shunt operations. Transforming growth factor (TGF)-ß1, tumor necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF), and total tau in the CSF were analyzed via enzyme-linked immunosorbent assay. RESULTS: The mean VEGF levels in the CSF of patients with SAH-induced hydrocephalus, INPH, and obstructive hydrocephalus were 239 ± 131, 239 ± 75, and 163 ± 122 pg/mL, respectively. The total tau concentrations in the CSF of the groups were 1139 ± 1900, 325 ± 325, and 1550 ± 2886 pg/mL, respectively. TNF-α values were 114 ± 34, 134 ± 38, and 55 ± 16 pg/mL, respectively. TGF-ß1 values were 953 ± 430, 869 ± 447, and 136 ± 63 pg/mL, respectively. A significant difference in TNF-α and TGF-ß1 levels was observed only between SAH-induced and chronic obstructive hydrocephalus, and between INPH and chronic obstructive hydrocephalus (p<0.01). CONCLUSIONS: No significant differences in the 4 CSF biomarker levels were observed between INPH and SAH-induced hydrocephalus, whereas CSF TNF-α and TGF-ß1 levels were increased compared to those in patients with chronic obstructive hydrocephalus. Post-SAH hydrocephalus and INPH are probably more destructive to neural tissues, and then stimulate the inflammatory reaction and healing process, compared with obstructive hydrocephalus.

Secondary normal pressure hydrocephalus in a patient with isolated frontal dilatation--an insight into pathophysiology?

Current theories of the pathophysiology of normal pressure hydrocephalus suggest the classical symptoms are a consequence of disruption of normal frontal function. We present the case of a 70-year-old patient with an isolated, frontal dilatation of his lateral ventricles in the presence of a complete triad as supportive of these theories.

Impact of Subjective Evaluations in Predicting Response to Ventriculoperitoneal Shunt for Idiopathic Normal Pressure Hydrocephalus.

BACKGROUND: Cerebrospinal fluid tap test is a common procedure to predict the efficacy of ventriculoperitoneal shunt for idiopathic normal pressure hydrocephalus. Objective tests after cerebrospinal fluid tap test are used to establish the surgical indication, but subjective improvements may also be important in selection of surgical candidates. The aim of this study was to evaluate surgical outcomes of patients with ventriculoperitoneal shunt for idiopathic normal pressure hydrocephalus, comparing patients showing objective improvement with patients improving only on subjective assessments. METHODS: In this retrospective analysis, patients were divided into 2 groups: group 1 included patients with improvement on objective evaluation after cerebrospinal fluid tap test; group 2 included patients who showed only subjective improvement. The surgical outcomes of the 2 groups were compared. RESULTS: Of 28 included patients, 17 were objective responders (group 1), and 11 were subjective responders (group 2). Clinical and radiological characteristics were similar. The only significant difference was the baseline Berg Balance Scale, which was lower in objective responders (P = 0.0015). At 3 months after surgery and at last follow-up, there was no difference in surgical outcomes between the 2 groups. However, in the group of subjective responders, a continuous improvement for incontinence and gait was more frequently observed (P = 0.04 and P < 0.001, respectively). CONCLUSIONS: Surgical outcomes after ventriculoperitoneal shunt were similar between the 2 groups, with a more favorable trend in terms of symptom improvement for subjective responders. Subjective assessment seems to be an important factor to consider in preoperative evaluation.

Lack of shunt response in suspected idiopathic normal pressure hydrocephalus with Alzheimer disease pathology.

To determine the impact of cortical Alzheimer disease pathology on shunt responsiveness in individuals treated for idiopathic normal pressure hydrocephalus (iNPH), 37 patients clinically diagnosed with iNPH participated in a prospective study in which performance on neurologic, psychometric, and gait measures before and 4 months after shunting was correlated with amyloid ß plaques, neuritic plaques, and neurofibrillary tangles observed in cortical biopsies obtained during shunt insertion. No complications resulted from biopsy acquisition. Moderate to severe pathology was associated with worse baseline cognitive performance and diminished postoperative improvement on NPH symptom severity scales, gait measures, and cognitive instruments compared to patients lacking pathology.

The genesis of low pressure hydrocephalus.

BACKGROUND: Low pressure hydrocephalus (LPH) is an uncommon entity. Recognition of this treatable condition is important when clinicians are faced with the paradox of symptomatic hydrocephalus despite low intracranial pressures (ICP). Its etiology remains enigmatic. METHODS: We identified patients with LPH from the prospective, inpatient neuro-intensive care database over a 4-year period (2006-2010). RESULTS: Nine patients with LPH were identified over a 4-year period. The time from diagnosis of the initial neurosurgical condition to development of LPH varied from 7 days to 5 years. The sub-zero drainage method of Pang and Altschuler was successful in all cases. LPH was accompanied by transependymal edema in five patients despite low ICP. Four patients developed LPH during their initial admission for intracranial bleeding. As patients entered the LPH state, the ICP remained in a normal range yet daily CSF output from the external ventricular drain was reduced. When LPH patients were drained at sub-zero levels, daily CSF output exceeded baseline values for several days and then receded to baseline. Long-term management was achieved with low pressure shunt systems: six programmable shunts; one valveless ventriculoperitoneal shunt; two ventriculopleural shunts. Conditions most commonly associated with LPH are: subarachnoid hemorrhage, chronic hydrocephalus, brain tumors, and chronic CNS infections. CONCLUSIONS: Low pressure hydrocephalus is a challenging diagnosis. The genesis of LPH was associated with a drop in EVD output, symptomatic ventriculomegaly, and a remarkable absence of intracranial hypertension. When LPH was treated with the sub-zero method, a 'diuresis' of CSF ensued. These observations support a Darcy's flux of brain interstitial fluid due to altered brain poroelastance; in simpler terms, a boggy brain state.