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

2016 ◽  
Vol 41 (3) ◽  
pp. E6 ◽  
Author(s):  
Badih Daou ◽  
Petra Klinge ◽  
Stavropoula Tjoumakaris ◽  
Robert H. Rosenwasser ◽  
Pascal Jabbour
Keyword(s):  
Clinical Improvement ◽  
Head Trauma ◽  
Normal Pressure Hydrocephalus ◽  
Clinical Manifestations ◽  
Normal Pressure ◽  
Shunt Placement ◽  
Grading Scale ◽  
The Mean ◽  
Epidemiological Characteristics

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.

scholarly journals Prevalence of Cervical Stenosis and Myelopathy in Patients With Idiopathic Normal Pressure Hydrocephalus

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Ryan M Naylor ◽  
Karina Lenartowicz ◽  
Jonathan Graff-Radford ◽  
Jeremy Cutsforth-Gregory ◽  
Benjamin D Elder
Keyword(s):  
Cervical Spine ◽  
Normal Pressure Hydrocephalus ◽  
Cervical Myelopathy ◽  
Clinical Manifestations ◽  
Normal Pressure ◽  
Idiopathic Normal Pressure Hydrocephalus ◽  
Decompression Surgery ◽  
Consecutive Series ◽  
Cervical Stenosis ◽  
Shunt Placement

Abstract INTRODUCTION Both idiopathic normal pressure hydrocephalus (iNPH) and cervical myelopathy may result in progressive gait impairment. It is possible that some of the patients who do not respond to shunting despite a positive tap test may have gait dysfunction from cervical myelopathy. The objective of this study was to determine the prevalence of cervical stenosis with or without myelopathy in patients with iNPH. METHODS We screened a consecutive series of patients who underwent shunt placement for iNPH for comorbid cervical stenosis. Clinical manifestations of iNPH and cervical myelopathy, grade of cervical stenosis based on previously published criteria, cervical spine surgical intervention, timing of intervention, and outcomes were recorded. RESULTS A total of 42 patients with iNPH were included for analysis. Slightly more patients were male (65%), with a mean age of 75 yr (SD 7 yr) for the entire cohort. All patients presented with gait disturbances and underwent cervical spine MRI. 30/42 (71%) had at least cervical stenosis, while 7/42 (17%) had significant (grade 2-3) cervical stenosis with myelopathy requiring surgical decompression. All patients with grade 2-3 cervical stenosis and symptoms of cervical myelopathy in addition to iNPH underwent cervical decompression surgery. CONCLUSION Clinically significant cervical stenosis is highly prevalent in patients with iNPH, though this finding requires validation in a larger population. Based on these results, cervical imaging should be considered preoperatively or in patients whose gait does not improve after shunt placement.

Ventriculoperitoneal Shunting of Idiopathic Normal Pressure Hydrocephalus Increases Midbrain Size: A Potential Mechanism for Gait Improvement

Neurosurgery ◽  
2006 ◽  
Vol 59 (4) ◽  
pp. 847-851 ◽  
Author(s):  
J Mocco ◽  
Matthew I. Tomey ◽  
Ricardo J. Komotar ◽  
William J. Mack ◽  
Steven J. Frucht ◽  
...  
Keyword(s):  
Normal Pressure Hydrocephalus ◽  
Ventriculoperitoneal Shunt ◽  
Medical Center ◽  
Normal Pressure ◽  
Idiopathic Normal Pressure Hydrocephalus ◽  
Cross Sectional ◽  
Mean Values ◽  
Shunt Placement ◽  
Ventriculoperitoneal Shunting ◽  
The Mean

Abstract OBJECTIVE: Idiopathic normal pressure hydrocephalus (INPH) is characterized by a classic clinical triad of symptoms, including dementia, urinary incontinence, and gait disturbance. Recent work has demonstrated that the maximal midbrain anteroposterior (AP) diameter is significantly smaller in patients with INPH than in healthy, age-matched controls. The current study was undertaken to determine the effect of ventriculoperitoneal shunt placement on midbrain dimensions in INPH patients. METHODS: Twelve consecutive INPH patients undergoing ventriculoperitoneal shunt placement with pre- and postoperative computed tomographic scans at the Columbia University Medical Center were enrolled. Each patient's pre- and postoperative maximum AP and left-to-right diameters of the midbrain at the pontomesencephalic junction were independently measured in a blinded fashion by two of the authors. The average value of each dimension was computed by calculating the mean values of the measurements of the two observers. RESULTS: Both the mean AP diameter (preoperative mean, 2.06 ± 0.04 cm; postoperative mean, 2.27 ± 0.05; P = 0.0007) and left-to-right diameter (preoperative mean, 2.80 ± 0.07; postoperative mean, 3.03 ± 0.08; P = 0.0029) increased from pre- to postoperative imaging. The approximate cross-sectional area determined as the product of AP and left-to-right diameters also increased from pre- to postoperative images (preoperative mean, 5.79 ± 0.22 cm2; postoperative mean, 6.90 ± 0.25 cm2; P = 0.00049). CONCLUSION: This study provides supportive evidence that midbrain cytoarchitecture may play a role in the pathophysiology and post-ventriculoperitoneal shunt gait improvement of INPH patients.

scholarly journals B-32 The Use of Repeat Neuropsychological Assessment to Guide Treatment of Possible Normal Pressure Hydrocephalus in a Complex Case

2019 ◽  
Vol 34 (6) ◽  
pp. 978-978
Author(s):  
S Schneider ◽  
E Weiss ◽  
R Facchini ◽  
S Shagalow ◽  
S Jacobs ◽  
...  
Keyword(s):  
Neuropsychological Assessment ◽  
Normal Pressure Hydrocephalus ◽  
Normal Pressure ◽  
Complex Case ◽  
Communicating Hydrocephalus ◽  
Shunt Placement ◽  
Mild Improvement ◽  
Inpatient Settings ◽  
Outpatient Settings

Abstract Objective Normal Pressure Hydrocephalus (NPH) is a condition that is characterized by the buildup of cerebrospinal fluid (CSF) in the brain that can cause urinary incontinence, gait disturbance, and cognitive impairment. NPH can be progressive but may be managed or reversed with shunt placement. External Lumbar Drainage (ELD) trials in determining if shunt placement is appropriate are common, but the role of repeat neuropsychological assessments during ELD procedures is not well documented in the literature. Repeat, pre-, peri and post- ELD trial, assessment in a complex case of possible NPH is presented. Method 33-year-old Hispanic English-Speaking female with cognitive/memory complaints following intraventricular hemorrhage (IVH) secondary to vasculopathy was initially seen for post IVH outpatient neuropsychological evaluation. MRI showed enlarged ventricles/communicating hydrocephalus and workup for NPH was initiated. Repeat inpatient evaluations were completed during the ELD trial, with annual outpatient neuropsychological follow-up. Results Gait evaluation was inconclusive. Inpatient testing demonstrated minor improvement immediately following ELD opening, but performances were variable across the 4 days of re-evaluation. Shunt placement was rejected due to neuropsychological findings. Outpatient follow-up of patient over several years has demonstrated mild improvement and not evidence of cognitive decline since ELD trial. Conclusions Assessment of cognitive functioning in outpatient and inpatient settings before, during, and for several years following ELD testing was beneficial to ascertain the decision not to place a shunt. Repeat neuropsychological assessment in inpatient and outpatient settings provided crucial information for guiding treatment decisions.

Volumetric measurements in the detection of reduced ventricular volume in patients with normal-pressure hydrocephalus whose clinical condition improved after ventriculoperitoneal shunt placement

2002 ◽  
Vol 97 (1) ◽  
pp. 73-79 ◽  
Author(s):  
Richard C. Anderson ◽  
Jessica J. Grant ◽  
Robert de la Paz ◽  
Steven Frucht ◽  
Robert R. Goodman
Keyword(s):  
Clinical Improvement ◽  
Normal Pressure Hydrocephalus ◽  
Normal Pressure ◽  
Ventricular Volume ◽  
Ventricular Size ◽  
Content Type ◽  
Shunt Placement ◽  
Lateral Ventricles ◽  
Fine Print ◽  
Volumetric Measurements

Object. The syndrome of normal-pressure hydrocephalus (NPH) refers to the clinical triad of gait disturbance, dementia, and urinary incontinence in association with idiopathic ventriculomegaly and normal intracranial pressure. Ventriculoperitoneal (VP) shunt placement often yields significant clinical improvements, sometimes without apparent reduction of ventricular size. The authors hypothesized that careful volumetric measurements would show a decrease in ventricular volume in these patients. Methods. Twenty consecutive patients with NPH underwent placement of VP shunts equipped with programmable valves. In 11 patients pre- and postoperative neuroimaging was performed, which allowed volumetric analysis. Volumetric measurements of the lateral ventricles were calculated in triplicate by National Institutes of Health image-processing software to assess standard computerized tomography (CT) scans (eight patients) or magnetic resonance (MR) images (three patients) obtained before and after shunt placement. Ventricular volumes were also assessed by an independent neuroradiologist. Postoperative studies were performed at a time of clinical improvement, between 1 and 9 months postsurgery (mean 5 months). Preoperative and postoperative Unified Parkinson's Disease Rating Scale evaluations were performed in four patients. Significant clinical improvement occurred in all patients after shunt placement (mean follow-up period 17.5 months). Although 10 (91%) of 11 patients demonstrated a calculable decrease in volume in the lateral ventricles (mean decrease 39%), formal interpretation of neuroimages indicated a definite decrease in lateral ventricular volume in only three (27%) of 11 patients. Conclusions. Volumetric measurements obtained to compare preoperative and postoperative CT or MR studies obtained in patients with NPH in whom clinical improvement was seen after shunt placement surgery show a demonstrable decrease in ventricular size. Volumetric measurements may be helpful in clinical assessment postoperatively and in guiding programmable valve pressure settings.

Selection of patients with idiopathic normal-pressure hydrocephalus for shunt placement: a single-institution experience

2010 ◽  
Vol 113 (1) ◽  
pp. 64-73 ◽  
Author(s):  
Carmelo Anile ◽  
Pasquale De Bonis ◽  
Alessio Albanese ◽  
Alessandro Di Chirico ◽  
Annunziato Mangiola ◽  
...  
Keyword(s):  
Normal Pressure Hydrocephalus ◽  
Normal Pressure ◽  
Idiopathic Normal Pressure Hydrocephalus ◽  
Csf Shunt ◽  
Group Iii ◽  
Shunt Placement ◽  
Group I ◽  
Csf Hydrodynamics ◽  
The Mean ◽  
Group Ii

Object The ability to predict outcome after shunt placement in patients with idiopathic normal-pressure hydrocephalus (NPH) represents a challenge. To date, no single diagnostic tool or combination of tools has proved capable of reliably predicting whether the condition of a patient with suspected NPH will improve after a shunting procedure. In this paper, the authors report their experience with 120 patients with the goal of identifying CSF hydrodynamics criteria capable of selecting patients with idiopathic NPH. Specifically, they focused on the comparison between CSF-outflow resistance (R-out) and intracranial elastance (IE). Methods Between January 1977 and December 2005, 120 patients in whom idiopathic NPH had been diagnosed (on the basis of clinical findings and imaging) underwent CSF hydrodynamics evaluation based on an intraventricular infusion test. Ninety-six patients underwent CSF shunt placement: 32 between 1977 and 1989 (Group I) on the basis of purely clinical and radiological criteria; 44 between 1990 and 2002 (Group II) on the basis of the same criteria as Group I and because they had an IE slope > 0.25; and 20 between 2003 and 2005 (Group III) on the basis of the same criteria as Group II but with an IE slope ≥ 0.30. Outcomes were evaluated by means of both Stein-Langfitt and Larsson scores. Patients' conditions were considered improved when there was a stable decrease (at 6- and 12-month follow-up) of at least 1 point in the Stein-Langfitt score and 2 points in the Larsson score. Results Group I: while no statistically significant difference in mean R-out value between improved and unimproved cases was observed, a clear-cut IE slope value of 0.25 differentiated very sharply between unimproved and improved cases. Group II: R-out values in the 2 unimproved cases were 20 and 47 mm Hg/ml/min, respectively. The mean IE slope in the improved cases was 0.56 (range 0.30–1.4), while the IE slopes in the 2 unimproved cases were 0.26 and 0.27. Group III: the mean IE slope was 0.51 (range 0.31–0.7). The conditions of all patients improved after shunting. A significant reduction of the Evans ratio was observed in 34 (40.5%) of the 84 improved cases and in none of the unimproved cases. Conclusions Our strategy based on the analysis of CSF pulse pressure parameters seems to have a great accuracy in predicting surgical outcome in clinical practice.

scholarly journals Development of the Brazilian Portuguese version of the “Grading scale for idiopathic normal pressure hydrocephalus”: cross-cultural adaptation, reliability and validity

2018 ◽  
Vol 76 (10) ◽  
pp. 692-696
Author(s):  
Maria Izabel Romão Lopes ◽  
Juliana Benevenuto Tornai ◽  
Fernanda Letkaske de Miranda Jeng ◽  
Bianca di Virgilio Lopes ◽  
Gabriel André da Silva Mendes ◽  
...  
Keyword(s):  
Normal Pressure Hydrocephalus ◽  
Cultural Adaptation ◽  
Reliability And Validity ◽  
Normal Pressure ◽  
Cross Cultural ◽  
Idiopathic Normal Pressure Hydrocephalus ◽  
Cross Cultural Adaptation ◽  
Portuguese Version ◽  
Grading Scale ◽  
The Mean

ABSTRACT Objective: The current study translated to Portuguese and validated the normal pressure hydrocephalus (NPH) scale originally developed in English as the Grading Scale for Idiopathic Normal Pressure Hydrocephalus. Methods: Following Guillemin's validation protocol, the last version of the Portuguese NPH scale was applied to 121 consecutive patients with a diagnosis of normal pressure hydrocephalus (73 men and 48 women) from the Group of Cerebral Hydrodynamics from July 2010 to March 2012. Results: The mean age was 71.09 years old, ranging from 35 to 92 years. The rate of agreement and reproducibility was high, as confirmed by Cohen's Kappa coefficient, with excellent intraobserver correlation for the NPH scale items individually evaluated: gait (0.80), dementia (0.90) and incontinence (0.87). Conclusions: The Portuguese version of the Grading Scale for Idiopathic Normal Pressure Hydrocephalus was successfully translated and validated for use in Brazilian patients.

scholarly journals AGR - 1 The Use of Repeat Neuropsychological Assessment to Guide Treatment of Possible Normal Pressure Hydrocephalus in a Complex Case

2019 ◽  
Vol 34 (6) ◽  
pp. 830-830
Author(s):  
S Schneider ◽  
E Weiss
Keyword(s):  
Neuropsychological Assessment ◽  
Normal Pressure Hydrocephalus ◽  
Normal Pressure ◽  
Complex Case ◽  
Communicating Hydrocephalus ◽  
Shunt Placement ◽  
Mild Improvement ◽  
Inpatient Settings ◽  
Outpatient Settings

Abstract Objective Normal Pressure Hydrocephalus (NPH) is a condition that is characterized by the buildup of cerebrospinal fluid (CSF) in the brain that can cause urinary incontinence, gait disturbance, and cognitive impairment. NPH can be progressive but may be managed or reversed with shunt placement. External Lumbar Drainage (ELD) trials in determining if shunt placement is appropriate are common, but the role of repeat neuropsychological assessments during ELD procedures is not well documented in the literature. Repeat, pre, peri and post- ELD trial, assessment in a complex case of possible NPH is presented. Method 33-year-old Hispanic English-Speaking female with cognitive/memory complaints following intraventricular hemorrhage (IVH) secondary to vasculopathy was initially seen for post IVH outpatient neuropsychological evaluation. MRI showed enlarged ventricles/communicating hydrocephalus and workup for NPH was initiated. Repeat inpatient evaluations were completed during the ELD trial, with annual outpatient neuropsychological follow-up. Results Gait evaluation was inconclusive. Inpatient testing demonstrated minor improvement immediately following ELD opening, but performances were variable across the 4 days of re-evaluation. Shunt placement was rejected due to neuropsychological findings. Outpatient follow-up of patient over several years has demonstrated mild improvement and not evidence of cognitive decline since ELD trial. Conclusions Assessment of cognitive functioning in outpatient and inpatient settings before, during, and for several years following ELD testing was beneficial to ascertain the decision not to place a shunt. Repeat neuropsychological assessment in inpatient and outpatient settings provided crucial information for guiding treatment decisions.

scholarly journals Relatively Reduced Default Mode Network Connectivity in Comparison to The Severity of White Matter Involvement is Associated With Severe Memory Deficits and Poor Cognitive Outcomes in Patients With Idiopathic Normal Pressure Hydrocephalus.

2020 ◽  
Author(s):  
Shigenori Kanno ◽  
Kun-ichi Ogawa ◽  
Hiroaki Kikuchi ◽  
Masako Toyoshima ◽  
Nobuhito Abe ◽  
...  
Keyword(s):  
White Matter ◽  
Normal Pressure Hydrocephalus ◽  
Normal Pressure ◽  
Memory Deficits ◽  
Cognitive Outcomes ◽  
White Matter Integrity ◽  
Shunt Placement ◽  
Immediate Recall ◽  
Brain White Matter ◽  
The Mean

Abstract Background: The aim of this study was to investigate whether default mode network (DMN) connectivity and brain white matter integrity at baseline were associated with severe cognitive impairments at baseline and poor cognitive outcomes after shunt placement in patients with idiopathic normal pressure hydrocephalus (iNPH).Methods: Twenty consecutive patients with iNPH whose symptoms were followed for 6 months after shunt placement and 10 healthy controls (HCs) were enrolled. DMN connectivity and brain white matter integrity in patients with iNPH at baseline were detected by performing resting-state functional magnetic resonance imaging with independent component analysis and by using diffusion weighted imaging with tract-based spatial statistics, respectively. Performance on the neuropsychological tests for memory and executive functions and gait test was assessed in patients with iNPH at baseline and 6 months after shunt placement.Results: The mean DMN connectivity in the iNPH group was significantly reduced compared with that in the HC group and was significantly positively correlated with the scores of the Rey auditory verbal learning test (RAVLT) immediate recall and the frontal assessment battery (FAB). The mean fractional anisotropy of the whole-brain white matter skeleton in the iNPH group was significantly lower than that in the HC group. We divided the patients with iNPH into relatively preserved and reduced DMN connectivity groups using the indexes of DMN connectivity and white matter integrity. The reduced DMN connectivity group showed significantly worse performance on RAVLT at baseline and significantly worse improvement of RAVLT immediate recall and FAB scores compared with the preserved DMN connectivity group. Moreover, the RAVLT immediate score/the FAB score ratio highly distinguished the patients with relatively preserved DMN connectivity from those with relatively reduced DMN connectivity.Conclusions: Our findings indicated that iNPH patients with relatively reduced DMN connectivity in comparison to the severity of brain white matter involvement are associated with severe memory deficits at baseline and poorer cognitive outcomes after shunt placement. In addition, DMN connectivity/brain white matter integrity and RAVLT immediate score/FAB score ratios are useful predictors of poor cognitive outcomes after shunt placement.

Normal Pressure Hydrocephalus in a Patient with Myotonic Dystrophy: Case Report with a 10-Year Follow-up

Neurosurgery ◽  
2006 ◽  
Vol 58 (4) ◽  
pp. E796-E796 ◽  
Author(s):  
Maxime Delavallée ◽  
Christian Raftopoulos
Keyword(s):  
Myotonic Dystrophy ◽  
Clinical Improvement ◽  
Normal Pressure Hydrocephalus ◽  
Ventriculoperitoneal Shunt ◽  
Normal Pressure ◽  
Clinical Feature ◽  
Long Term Memory ◽  
Complete Evaluation

Abstract OBJECTIVE AND IMPORTANCE: Myotonic dystrophy (MD) is the most common adult muscular dystrophy involving multiple organs. Normal pressure hydrocephalus (NPH) is characterized by gait apraxia, urinary incontinence, and dementia. NPH in association with MD has been reported in only three cases. This report provides for the first time the complete evaluation, treatment, and long-term follow-up of a patient with NPH and MD. CLINICAL PRESENTATION: A 61-year-old man known to have MD complained of 4 years of progressive deterioration of long-term memory and gait disturbance, which was the main clinical feature. Computed tomography scan and magnetic resonance imaging showed ventricular enlargement. Intracranial pressure monitoring showed B waves with amplitude superior to 9 mm Hg in more than 5% of the recording. TECHNIQUE: We performed a ventriculoperitoneal shunt with clear postoperative improvement, confirming the diagnosis of NPH. The clinical improvement has remained stable through prolonged follow-up. CONCLUSION: Association between MD and NPH could be more than coincidental, and it is important to recognize this potential insidious association because a ventriculoperitoneal shunt can provide excellent long-term clinical improvement.

Outcome of Shunting in Idiopathic Normal-pressure Hydrocephalus and the Value of Outcome Assessment in Shunted Patients

Neurosurgery ◽  
2005 ◽  
Vol 57 (suppl_3) ◽  
pp. S2-40-S2-52 ◽  
Author(s):  
Petra Klinge ◽  
Anthony Marmarou ◽  
Marvin Bergsneider ◽  
Norman Relkin ◽  
Peter McL. Black
Keyword(s):  
Outcome Assessment ◽  
Clinical Improvement ◽  
Normal Pressure Hydrocephalus ◽  
Normal Pressure ◽  
Idiopathic Normal Pressure Hydrocephalus ◽  
Long Term Results ◽  
Shunt Treatment ◽  
Criteria For Selection

Abstract OBJECTIVE: To develop guidelines for assessing shunt outcome in patients with idiopathic normal-pressure hydrocephalus (INPH). To date, the literature available on this topic has been marked by disparate definitions of clinical improvement, varying postoperative follow-up protocols and periods, and substantial differences in the postoperative management. Because specific criteria for defining clinical improvement are seldom reported, conclusions drawn about shunt outcome may be subjective. METHODS: A MEDLINE search back to 1966 was undertaken using the query NPH, normal-pressure hydrocephalus, shunting, shunt treatment, shunt response, outcome, and clinical outcome. The criteria for selection were studies that included INPH from 1966 to the present in which the outcome of INPH was reported in patient groups of 20 or more. RESULTS: To date, there is no standard for outcome assessment of shunt treatment in INPH. The variable improvement rates reported are not only because of different criteria for selection of patients but also because of different postoperative assessment procedures and follow-up intervals. CONCLUSION: Studies that have established fixed protocols for follow-up have shown that short- and long-term periods after shunting are determined by many factors. Whereas short-term results were more likely to be influenced by shunt-associated risks, long-term results were independent of factors inherent to the shunt procedure and shunt complications, i.e., death and morbidity related to concomitant cerebrovascular and vascular diseases. Studies have shown that beyond 1 year after surgery, these factors definitely influence the clinical effect of shunting, making the 1-year postshunt period a potential determinant of the shunt outcome. Guidelines for outcome assessment were developed on the basis of the available evidence and consensus of expert opinion.

Sign in / Sign up

Export Citation Format

Share Document