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Lalou AD, Czosnyka ZH, Czosnyka M. Observational study of intracranial pressure instability in patients with pseudotumour cerebri syndrome. BRAIN & SPINE 2024; 4:102758. [PMID: 38510634 PMCID: PMC10951771 DOI: 10.1016/j.bas.2024.102758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 01/15/2024] [Accepted: 01/21/2024] [Indexed: 03/22/2024]
Abstract
Introduction A fixed CSF pressure (CSFp) of 25 cmH2O (18 mmHg) has been utilised to date to define and classify pseudotumour cerebri syndrome (PTCS). Furthermore, ICP monitoring, and CSF infusion tests have not been frequently performed in this group of patients. Research question We aimed to report typical, unusual and unstable patterns of ICP in patients with PTCS. Material and methods We reviewed the recordings of CSF infusion tests and overnight ICP monitoring of patients with suspected or confirmed IIH between January 2003-December 2020.We excluded all patients with a shunt in situ and selected recordings that represented unstable patterns of ICP changes in PTCS. Results 463 CSF infusion tests and 26 ICP monitorings of PTCS patients had been performed in this timeframe. We divided results of observed pattern into two group: those with known venous sinus measurements (Group A) and those without (Group B). Observed recordings formed a total of 5 and 4 different patterns respectively, based on the behaviour of ICP and slow waves at rest, overnight, and during infusion as well as in relationship to the clinical presentation of each patient. Discussion and conclusion Accurate monitoring of ICP in PTCS is quintessential. Full understanding of each element of its pathophysiology and their interaction would be essential and include quantification of the CSF pressure not only as a number, but also with consideration of its dynamic contents. Cerebral venous pressure measurements and/or monitoring may be useful. Consideration of the presence or absence of papilloedema in the context of disturbed CSF dynamics could reveal further diagnostic and therapeutic insights.
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Affiliation(s)
- Afroditi D. Lalou
- Department of Clinical Neurosciences, Division of Neurosurgery, Brain Physics Laboratory, University of Cambridge & Cambridge University Hospital NHS Foundation Trust, United Kingdom
- Department of Neurology, King's College Hospital NHS Foundation Trust, London, United Kingdom
- Department of Radiation Sciences, Faculty of Medicine, Umeå University, Umeå, Sweden
| | - Zofia H. Czosnyka
- Department of Clinical Neurosciences, Division of Neurosurgery, Brain Physics Laboratory, University of Cambridge & Cambridge University Hospital NHS Foundation Trust, United Kingdom
| | - Marek Czosnyka
- Department of Clinical Neurosciences, Division of Neurosurgery, Brain Physics Laboratory, University of Cambridge & Cambridge University Hospital NHS Foundation Trust, United Kingdom
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Signorelli F, Trevisi G, Visocchi M, Anile C. Comparison Between Ventricular and Spinal Infusion Tests in Suspected Normal Pressure Hydrocephalus. ACTA NEUROCHIRURGICA. SUPPLEMENT 2023; 135:219-222. [PMID: 38153473 DOI: 10.1007/978-3-031-36084-8_34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
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 >12 mmHg and 23 a Rout <12 mmHg. Of the 50 patients in the IVKT group with pathological elastance (92%), 38 also had a Rout >12 mmHg and 12 a Rout <12 mmHg.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.
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Affiliation(s)
- Francesco Signorelli
- Department of Neurosurgery, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Institute of Neurosurgery, Catholic University of Rome, Rome, Italy
| | - Gianluca Trevisi
- Neurosurgical Unit, Ospedale Spirito Santo, Pescara, Italy
- Department of Neurosciences, Imaging and Clinical Sciences, "G. D'Annunzio" University, Chieti-Pescara, Italy
| | | | - Carmelo Anile
- Neurosurgery, Catholic University School of Medicine, Rome, Italy
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Thavarajasingam SG, El-Khatib M, Rea M, Russo S, Lemcke J, Al-Nusair L, Vajkoczy P. Clinical predictors of shunt response in the diagnosis and treatment of idiopathic normal pressure hydrocephalus: a systematic review and meta-analysis. Acta Neurochir (Wien) 2021; 163:2641-2672. [PMID: 34235589 PMCID: PMC8437907 DOI: 10.1007/s00701-021-04922-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/13/2021] [Indexed: 11/29/2022]
Abstract
Background Positive shunt response (SR) remains the gold standard for diagnosing idiopathic normal pressure hydrocephalus (iNPH). However, multiple pathologies mimic iNPH symptoms, making it difficult to select patients who will respond to shunt surgery. Although presenting features, extended lumbar drainage (ELD), infusion test (IT), intracranial pressure monitoring (ICPM), and tap test (TT) have been used to predict SR, uncertainty remains over which diagnostic test to choose. Objective To conduct a systematic review and meta-analysis to identify clinical predictors of shunt responsiveness, evaluate their diagnostic effectiveness, and recommend the most effective diagnostic tests. Methods Embase, MEDLINE, Scopus, PubMed, Google Scholar, and JSTOR were searched for original studies investigating clinical predictors of SR in iNPH patients. Included studies were assessed using the QUADAS-2 tool, and eligible studies were evaluated using univariate and bivariate meta-analyses. Results Thirty-five studies were included. Nine studies discussed the diagnostic use of presenting clinical features, 8 studies ELD, 8 studies IT, 11 studies ICPM, and 6 studies TT. A meta-analysis of 21 eligible studies was conducted for TT, ELD, IT, and ICPM. ICPM yielded the highest diagnostic effectiveness, with diagnostic odds ratio (DOR) = 50.9 and area under curve (AUC) = 0.836. ELD yielded DOR = 27.70 and AUC = 0.753, IT had DOR = 5.70 and AUC = 0.729, and TT scored DOR = 3.86 and AUC = 0.711. Conclusion Intraparenchymal ICPM is statistically the most effective diagnostic test, followed by ELD, IT, and lastly TT. Due to the higher accessibility of TT and IT, they are recommended to be used first line, using a timed-up-and-go improvement ≥ 5.6 s or a Rout cut-off range between 13 and 16 mmHg, respectively. Patients who test negative should ideally be followed up with ICPM, using mean ICP wave amplitude \documentclass[12pt]{minimal}
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\begin{document}$$\ge$$\end{document}≥ 3. Future research must use standardized methodologies for each diagnostic test and uniform criteria for SR to allow better comparison.
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Affiliation(s)
| | - Mahmoud El-Khatib
- Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Mark Rea
- Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Salvatore Russo
- Department of Neurosurgery, Imperial College Healthcare NHS Trust, London, United Kingdom
| | - Johannes Lemcke
- Department of Neurosurgery, Unfallkrankenhaus Berlin, Berlin, Germany
| | - Lana Al-Nusair
- Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Peter Vajkoczy
- Department of Neurosurgery, Charité-Universitätsmedizin Berlin, Berlin, Germany
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The Role of Cerebrospinal Fluid Dynamics in Normal Pressure Hydrocephalus Diagnosis and Shunt Prognostication. ACTA NEUROCHIRURGICA. SUPPLEMENT 2021. [PMID: 33839875 DOI: 10.1007/978-3-030-59436-7_69] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
BACKGROUND Over the years, there have been several reports and trials of the resistance to cerebrospinal fluid (CSF) outflow (Rout) in normal pressure hydrocephalus (NPH). This work aimed to revisit the utility of testing CSF circulation in a large population of patients clinically presenting with NPH. MATERIALS AND METHODS We retrospectively analyzed the data of 369 NPH patients-either shunted or with endoscopic third ventriculostomy (ETV)-in Cambridge between 1992 and 2018. We determined the patients' outcomes (improvement versus no improvement at 6 months) by applying a threshold on R out values and compared our results with those of existing literature. We also conducted a correlation analysis between all variables and calculated Chi-Statistics (as a measure of separability between improvement and no improvement outcomes) to determine a subset of variables which achieved the highest accuracy in prediction of outcome. RESULTS In our dataset, R out of 18 mmHg*min/mL achieved the highest Chi-statistics of 9.7 with p-value <0.01 when adjusted for age. In addition to R out, intracranial pressure (ICP) values at the baseline and plateau, CSF production rate and ICP amplitude to slope ratio showed significant Chi-Statistics values (more than 5). Using these variables, an overall accuracy of 0.70 ± 0.09 was achieved for prediction of the shunt outcome. CONCLUSION Rout can be used for selecting patients for shunt surgery but not for excluding patients from treatment. Critical, multivariable approaches are required to comprehend CSF dynamics and pressure-volume compensation in NPH. Outcome definition and assessment could also be brought to question.
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Lalou AD, Czosnyka M, Placek MM, Smielewski P, Nabbanja E, Czosnyka Z. CSF Dynamics for Shunt Prognostication and Revision in Normal Pressure Hydrocephalus. J Clin Med 2021; 10:jcm10081711. [PMID: 33921142 PMCID: PMC8071572 DOI: 10.3390/jcm10081711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/09/2021] [Accepted: 04/12/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Despite the quantitative information derived from testing of the CSF circulation, there is still no consensus on what the best approach could be in defining criteria for shunting and predicting response to CSF diversion in normal pressure hydrocephalus (NPH). OBJECTIVE We aimed to review the lessons learned from assessment of CSF dynamics in our center and summarize our findings to date. We have focused on reporting the objective perspective of CSF dynamics testing, without further inferences to individual patient management. DISCUSSION No single parameter from the CSF infusion study has so far been able to serve as an unquestionable outcome predictor. Resistance to CSF outflow (Rout) is an important biological marker of CSF circulation. It should not, however, be used as a single predictor for improvement after shunting. Testing of CSF dynamics provides information on hydrodynamic properties of the cerebrospinal compartment: the system which is being modified by a shunt. Our experience of nearly 30 years of studying CSF dynamics in patients requiring shunting and/or shunt revision, combined with all the recent progress made in producing evidence on the clinical utility of CSF dynamics, has led to reconsidering the relationship between CSF circulation testing and clinical improvement. CONCLUSIONS Despite many open questions and limitations, testing of CSF dynamics provides unique perspectives for the clinician. We have found value in understanding shunt function and potentially shunt response through shunt testing in vivo. In the absence of infusion tests, further methods that provide a clear description of the pre and post-shunting CSF circulation, and potentially cerebral blood flow, should be developed and adapted to the bed-space.
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Affiliation(s)
- Afroditi Despina Lalou
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK; (M.C.); (M.M.P.); (P.S.); (E.N.); (Z.C.)
- Correspondence: ; Tel.: +44-774-3567-585
| | - Marek Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK; (M.C.); (M.M.P.); (P.S.); (E.N.); (Z.C.)
- Institute of Electronic Systems, Faculty of Electronics and Information Sciences, Warsaw University of Technology, 00-661 Warsaw, Poland
| | - Michal M. Placek
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK; (M.C.); (M.M.P.); (P.S.); (E.N.); (Z.C.)
| | - Peter Smielewski
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK; (M.C.); (M.M.P.); (P.S.); (E.N.); (Z.C.)
| | - Eva Nabbanja
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK; (M.C.); (M.M.P.); (P.S.); (E.N.); (Z.C.)
| | - Zofia Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, UK; (M.C.); (M.M.P.); (P.S.); (E.N.); (Z.C.)
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Timing of intraventricular infusion test for diagnosing idiopathic normal pressure hydrocephalus. Acta Neurochir (Wien) 2020; 162:1011-1017. [PMID: 31912355 DOI: 10.1007/s00701-019-04168-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Accepted: 12/05/2019] [Indexed: 10/25/2022]
Abstract
BACKGROUND Infusion tests, which measure resistance to outflow (Rout), are used in selecting patients suspected for idiopathic normal pressure hydrocephalus (iNPH) for shunt surgery. Infusion tests can be performed through an external ventricular drain (EVD). A 24-hour time gap from EVD insertion to an infusion test is a routine practice at our department due to concerns that the surgical procedure might influence the test results in the immediate postoperative period. The objective of the study was to investigate if timing of an intraventricular infusion test influences the results of the test in patients suspected for iNPH. METHODS Ten patients scheduled for an intraventricular infusion test were included. Measurements of baseline intracranial pressure (ICP) and plateau ICP were obtained during constant rate intraventricular infusion test performed at two time points (1 and 24 h after EVD insertion) and Rout was calculated from these measures and compared within patients. RESULTS Eight patients completed both infusion tests. In one of the 18 infusion tests performed, it was not possible to define an ICP plateau and this infusion test was excluded, leaving 7 paired infusion tests. Median Rout was 12.9 mmHg/ml/min (range 7.0-22.0) 1 h after EVD insertion and 11.3 mmHg/ml/min (range 7.8-18.1) after 24 h. Overall, there were no statistically significant differences in Rout (P = 0.83), baseline ICP (P = 0.70), or plateau ICP (P = 0.81) between the recordings performed 1 h and 24 h after EVD insertion. For two of the seven patients with paired infusion tests, there was poor agreement between Rout values at 1 and 24 h. CONCLUSION Overall, Rout estimates do not change significantly between 1 and 24 h after EVD insertion. We therefore propose that infusion tests can be performed shortly after surgery to reduce the period of indwelling EVD and duration of hospitalization.
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Lalou AD, Levrini V, Czosnyka M, Gergelé L, Garnett M, Kolias A, Hutchinson PJ, Czosnyka Z. Cerebrospinal fluid dynamics in non-acute post-traumatic ventriculomegaly. Fluids Barriers CNS 2020; 17:24. [PMID: 32228689 PMCID: PMC7106631 DOI: 10.1186/s12987-020-00184-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 03/06/2020] [Indexed: 12/11/2022] Open
Abstract
Background Post-traumatic hydrocephalus (PTH) is potentially under-diagnosed and under-treated, generating the need for a more efficient diagnostic tool. We aim to report CSF dynamics of patients with post-traumatic ventriculomegaly. Materials and methods We retrospectively analysed post-traumatic brain injury (TBI) patients with ventriculomegaly who had undergone a CSF infusion test. We calculated the resistance to CSF outflow (Rout), AMP (pulse amplitude of intracranial pressure, ICP), dAMP (AMPplateau-AMPbaseline) and compensatory reserve index correlation coefficient between ICP and AMP (RAP). To avoid confounding factors, included patients had to be non-decompressed or with cranioplasty > 1 month previously and Rout > 6 mmHg/min/ml. Compliance was assessed using the elasticity coefficient. We also compared infusion-tested TBI patients selected for shunting versus those not selected for shunting (consultant decision based on clinical and radiological assessment and the infusion results). Finally, we used data from a group of shunted idiopathic Normal Pressure Hydrocephalus (iNPH) patients for comparison. Results Group A consisted of 36 patients with post-traumatic ventriculomegaly and Group B of 45 iNPH shunt responders. AMP and dAMP were significantly lower in Group A than B (0.55 ± 0.39 vs 1.02 ± 0.72; p < 0.01 and 1.58 ± 1.21 vs 2.76 ± 1.5; p < 0.01. RAP baseline was not significantly different between the two. Elasticity was higher than the normal limit in all groups (average 0.18 1/ml). Significantly higher Rout was present in those with probable PTH selected for shunting compared with unshunted. Mild/moderate hydrocephalus, ex-vacuo ventriculomegaly/encephalomalacia were inconsistently reported in PTH patients. Conclusions Rout and AMP were significantly lower in PTH compared to iNPH and did not always reflect the degree of hydrocephalus or atrophy reported on CT/MRI. Compliance appears reduced in PTH.
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Affiliation(s)
- Afroditi D Lalou
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital NHS Foundation Trust, Cambridge, UK.
| | - Virginia Levrini
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
| | - Marek Czosnyka
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
| | - Laurent Gergelé
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital NHS Foundation Trust, Cambridge, UK.,Department of Intensive Care, Hôpital privé de la Loire, Saint Etienne, France
| | - Matthew Garnett
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
| | - Angelos Kolias
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
| | - Peter J Hutchinson
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
| | - Zofia Czosnyka
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge and Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
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Validation of Davson's equation in patients suffering from idiopathic normal pressure hydrocephalus. Acta Neurochir (Wien) 2018. [PMID: 29520439 DOI: 10.1007/s00701-018-3497-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
INTRODUCTION The so-called Davson's equation relates baseline intracranial pressure (ICP) to resistance to cerebrospinal fluid outflow (Rout), formation of cerebrospinal fluid (If) and sagittal sinus pressure (PSS) There is a controversy over whether this fundamental equation is applicable in patients with normal pressure hydrocephalus (NPH). We investigated the relationship between Rout and ICP and also other compensatory, clinical and demographic parameters in NPH patients. METHOD We carried out a retrospective study of 229 patients with primary NPH who had undergone constant-rate infusion studies in our hospital. Data was recorded and processed using ICM+ software. Relationships between variables were sought by calculating Pearson product correlation coefficients and p values. RESULTS We found a significant, albeit weak, relationship between ICP and Rout (R = 0.17, p = 0.0049), Rout and peak-to-peak amplitude of ICP (AMP) (R = 0.27, p = 3.577e-05) and Rout and age (R = 0.16, p = 0.01306). CONCLUSIONS The relationship found between ICP and Rout provides indirect evidence to support disturbed Cerebrospinal fluid circulation as a key factor in disturbed CSF dynamics in NPH. Weak correlation may indicate that other factors-variable PSS and formation of CSF outflow-contribute heavily to linear model expressed by Davson's equation.
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Chen CPC, Huang YC, Chang CN, Chen JL, Hsu CC, Lin WY. Changes of cerebrospinal fluid protein concentrations and gait patterns in geriatric normal pressure hydrocephalus patients after ventriculoperitoneal shunting surgery. Exp Gerontol 2018; 106:109-115. [PMID: 29408782 DOI: 10.1016/j.exger.2018.01.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 01/07/2018] [Accepted: 01/31/2018] [Indexed: 10/18/2022]
Abstract
Normal pressure hydrocephalus (NPH) was the first type of dementia ever described that can be treated using ventriculoperitoneal shunting surgery. Three typical clinical symptoms of NPH include gait disturbance, progressive cognitive dysfunction, and urinary incontinence. Although there are articles that have discovered several cerebrospinal fluid (CSF) protein biomarkers associated with NPH; however, studies examining individual and total protein concentrations from the ventricular CSF before and after shunting surgery are lacking. This study used proteomics to calculate the CSF individual and total protein concentrations before, and one week, one month and three months after the shunting surgery. Parameters of cadence, step length, walking speed, and percentages of single- and double-limb support in a gait cycle were measured. Protein concentrations associated with anti-oxidation, aging, and in the prevention of neurotoxic agent production increased by at least 2-folds after the surgery, indicating that the brain may become less susceptible to neurodegeneration. These proteins were alpha-1B-glycoprotein, apolipoproteins A-1 & A-IV, prostaglandin-H2 D-isomerase, alpha-1-antitrypsin, and serotransferrin. In gait analysis, lower cadence, decreased double-limb support, longer step length, and increased single-limb support were observed after the surgery, indicating a more stable walking balance. These changes lasted for a period of at least 3 months. As a result, shunting surgery may be recommended for geriatric patients with confirmed diagnosis of normal pressure hydrocephalus.
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Affiliation(s)
- Carl P C Chen
- Department of Physical Medicine & Rehabilitation, Chang Gung Memorial Hospital at Linkou and College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan City, Taiwan.
| | - Yin-Cheng Huang
- Department of Neurosurgery, Chang Gung Memorial Hospital at Linkou and College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan City, Taiwan
| | - Chen-Nen Chang
- Department of Neurosurgery, Chang Gung Memorial Hospital at Linkou and College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan City, Taiwan
| | - Jean-Lon Chen
- Department of Physical Medicine & Rehabilitation, Chang Gung Memorial Hospital at Linkou and College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan City, Taiwan
| | - Chih-Chin Hsu
- Department of Physical Medicine & Rehabilitation, Chang Gung Memorial Hospital at Keelung and College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan City, Taiwan
| | - Wan-Ying Lin
- Department of Physical Medicine & Rehabilitation, Chang Gung Memorial Hospital at Linkou and College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan City, Taiwan
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Discriminant Analysis of Intracranial Volumetric Variables in Patients with Normal Pressure Hydrocephalus and Brain Atrophy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017. [DOI: 10.1007/5584_2017_75] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Eide PK. The correlation between pulsatile intracranial pressure and indices of intracranial pressure-volume reserve capacity: results from ventricular infusion testing. J Neurosurg 2016; 125:1493-1503. [PMID: 26918478 DOI: 10.3171/2015.11.jns151529] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The objective of this study was to examine how pulsatile and static intracranial pressure (ICP) scores correlate with indices of intracranial pressure-volume reserve capacity, i.e., intracranial elastance (ICE) and intracranial compliance (ICC), as determined during ventricular infusion testing. METHODS All patients undergoing ventricular infusion testing and overnight ICP monitoring during the 6-year period from 2007 to 2012 were included in the study. Clinical data were retrieved from a quality registry, and the ventricular infusion pressure data and ICP scores were retrieved from a pressure database. The ICE and ICC (= 1/ICE) were computed during the infusion phase of the infusion test. RESULTS During the period from 2007 to 2012, 82 patients with possible treatment-dependent hydrocephalus underwent ventricular infusion testing within the department of neurosurgery. The infusion tests revealed a highly significant positive correlation between ICE and the pulsatile ICP scores mean wave amplitude (MWA) and rise-time coefficient (RTC), and the static ICP score mean ICP. The ICE was negatively associated with linear measures of ventricular size. The overnight ICP recordings revealed significantly increased MWA (> 4 mm Hg) and RTC (> 20 mm Hg/sec) values in patients with impaired ICC (< 0.5 ml/mm Hg). CONCLUSIONS In this study cohort, there was a significant positive correlation between pulsatile ICP and ICE measured during ventricular infusion testing. In patients with impaired ICC during infusion testing (ICC < 0.5 ml/mm Hg), overnight ICP recordings showed increased pulsatile ICP (MWA > 4 mm Hg, RTC > 20 mm Hg/sec), but not increased mean ICP (< 10-15 mm Hg). The present data support the assumption that pulsatile ICP (MWA and RTC) may serve as substitute markers of pressure-volume reserve capacity, i.e., ICE and ICC.
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Affiliation(s)
- Per Kristian Eide
- Department of Neurosurgery, Oslo University Hospital-Rikshospitalet, and Faculty of Medicine, University of Oslo, Norway
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Kim DJ, Kim H, Kim YT, Yoon BC, Czosnyka Z, Park KW, Czosnyka M. Thresholds of resistance to CSF outflow in predicting shunt responsiveness. Neurol Res 2014; 37:332-40. [DOI: 10.1179/1743132814y.0000000454] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Long-term Outcomes After Shunt Implantation in Patients With Posttraumatic Hydrocephalus and Severe Conscious Disturbance. J Craniofac Surg 2014; 25:1280-3. [DOI: 10.1097/scs.0000000000000583] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Lemcke J, Meier U, Müller C, Fritsch MJ, Kehler U, Langer N, Kiefer M, Eymann R, Schuhmann MU, Speil A, Weber F, Remenez V, Rohde V, Ludwig HC, Stengel D. Safety and efficacy of gravitational shunt valves in patients with idiopathic normal pressure hydrocephalus: a pragmatic, randomised, open label, multicentre trial (SVASONA). J Neurol Neurosurg Psychiatry 2013; 84:850-7. [PMID: 23457222 PMCID: PMC3717598 DOI: 10.1136/jnnp-2012-303936] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To investigate whether gravitational valves reduce the risk of overdrainage complications compared with programmable valves in ventriculoperitoneal (VP) shunt surgery for idiopathic normal pressure hydrocephalus (iNPH). BACKGROUND Patients with iNPH may benefit from VP shunting but are prone to overdrainage complications during posture changes. Gravitational valves with tantalum balls are considered to reduce the risk of overdrainage but their clinical effectiveness is unclear. METHODS We conducted a pragmatic, randomised, multicentre trial comparing gravitational with non-gravitational programmable valves in patients with iNPH eligible for VP shunting. The primary endpoint was any clinical or radiological sign (headache, nausea, vomiting, subdural effusion or slit ventricle) of overdrainage 6 months after randomisation. We also assessed disease specific instruments (Black and Kiefer Scale) and Physical and Mental Component Scores of the Short Form 12 (SF-12) generic health questionnaire. RESULTS We enrolled 145 patients (mean (SD) age 71.9 (6.9) years), 137 of whom were available for endpoint analysis. After 6 months, 29 patients in the standard and five patients in the gravitational shunt group developed overdrainage (risk difference -36%, 95% CI -49% to -23%; p<0.001). This difference exceeded predetermined stopping rules and resulted in premature discontinuation of patient recruitment. Disease specific outcome scales did not differ between the groups although there was a significant advantage of the gravitational device in the SF-12 Mental Component Scores at the 6 and 12 month visits. CONCLUSIONS Implanting a gravitational rather than another type of valve will avoid one additional overdrainage complication in about every third patient undergoing VP shunting for iNPH.
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Affiliation(s)
- Johannes Lemcke
- Department of Neurosurgery, Unfallkrankenhaus Berlin, Warener Str 7, Berlin 12683, Germany.
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15
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Eide PK, Brean A. Lumbar cerebrospinal fluid pressure waves versus intracranial pressure waves in idiopathic normal pressure hydrocephalus. Br J Neurosurg 2007; 20:407-14. [PMID: 17439094 DOI: 10.1080/02688690601047312] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The aim of this study was to explore how the lumbar cerebrospinal fluid pressure (CSFP) waves recorded during lumbar infusion compared with the intracranial pressure (ICP) waves recorded, either during lumbar infusion or during long-term, overnight monitoring. For this purpose, we assessed 27 simultaneous lumbar CSFP/ICP recordings made during lumbar infusion and 27 long-term, overnight ICP recordings in 27 consecutive idiopathic normal pressure hydrocephalus (iNPH) patients. Pressure waves during lumbar infusion were explored by computing pulse pressure amplitude and mean single wave pressure of every corresponding CSFP/ICP wave pair; among our 27 lumbar CSFP/ICP recordings a total of 35,532 CSFP/ICP wave pairs were available for analysis. We as well computed mean values of pulse pressure amplitude (i.e. mean CSFP wave amplitude or mean ICP wave amplitude) and mean values of mean single wave pressure (i.e. mean CSFP or mean ICP) during consecutive 6-s time windows, as well as average values for the individual recordings. During lumbar infusion, the cerebrospinal fluid pulse pressure amplitudes were about 2 mmHg smaller than the corresponding intracranial pulse pressure amplitudes. The mean CSFP wave amplitudes recorded during lumbar infusion correlated significantly with the mean ICP wave amplitudes recorded either during lumbar infusion or during long-term, overnight ICP monitoring. In 21 of 27 lumbar infusion tests (78%), the presence of elevated lumbar mean CSFP waves was related to presence of elevated mean ICP wave amplitudes during long-term, overnight ICP monitoring. Hence, the lumbar cerebrospinal fluid pulse pressure amplitudes recorded during lumbar infusion could be used to predict the intracranial pulse pressure amplitudes recorded during long-term, overnight ICP monitoring.
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Affiliation(s)
- P K Eide
- Department of Neurosurgery, The National Hospital, Rikshospitalet, Oslo, Norway.
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16
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Eklund A, Smielewski P, Chambers I, Alperin N, Malm J, Czosnyka M, Marmarou A. Assessment of cerebrospinal fluid outflow resistance. Med Biol Eng Comput 2007; 45:719-35. [PMID: 17634761 DOI: 10.1007/s11517-007-0199-5] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2006] [Accepted: 05/12/2007] [Indexed: 10/23/2022]
Abstract
The brain and the spinal cord are contained in a cavity and are surrounded by cerebrospinal fluid (CSF), which provides physical support for the brain and a cushion against external pressure. Hydrocephalus is a disease, associated with disturbances in the CSF dynamics, which can be surgically treated by inserting a shunt or third ventriculostomy. This review describes the physiological background, modeling and mathematics, and the investigational methods for determining the CSF dynamic properties, with specific focus on the CSF outflow resistance, R out. A model of the cerebrospinal fluid dynamic system, with a pressure-independent R out, a pressure-dependent compliance and a constant formation rate of CSF is widely accepted. Using mathematical expressions calculated from the model, along with active infusion of artificial CSF and observation of corresponding change in ICP allows measurements of CSF dynamics. Distinction between normal pressure hydrocephalus and differential diagnoses, prediction of clinical response to shunting and the possibility of assessment of shunt function in vivo are the three most important applications of infusion studies in clinical practice.
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Affiliation(s)
- Anders Eklund
- Department of Biomedical Engineering and Informatics, Umeå University Hospital, 90185 Umeå, Sweden.
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17
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Kahlon B, Sjunnesson J, Rehncrona S. LONG-TERM OUTCOME IN PATIENTS WITH SUSPECTED NORMAL PRESSURE HYDROCEPHALUS. Neurosurgery 2007; 60:327-32; discussion 332. [PMID: 17290183 DOI: 10.1227/01.neu.0000249273.41569.6e] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
OBJECTIVE
To evaluate the outcome of patients with suspected normal pressure hydrocephalus at 6 months and 5 years after shunt surgery.
METHODS
Seventy-five patients (mean age, 72.5 6 9 yr), with normal pressure hydrocephalus symptoms were included. Fifty-four patients with positive lumbar infusion and/or cerebrospinal fluid tap tests received a cerebrospinal fluid shunt, whereas 21 patients with negative test results did not undergo operation. Walk, reaction time, memory, and identical forms tests were used as baseline (before surgery) tests and were repeated at short- (6.1 6 4.6 mo) and long-term (5.5 6 1.4 yr) follow-up evaluations. Activities of daily life functions were assessed using the Barthel index.
RESULTS
At the 6-month follow-up examination, 83% of the operated patients improved in gait, 65% improved in reaction time, 46% improved in memory, and 31% improved in identical forms tests; 96% found themselves subjectively improved. Because of unrelated mortality (37%) and declining general health from comorbidity, only 27 patients were available for the 5-year follow-up evaluation. Twenty-three of these patients had been treated with a shunt and had a remaining improvement in close to 40% in gait and reaction time, whereas fewer than 10% had an improvement in cognitive tests. Fifty-six percent reported subjective improvement compared with preoperative findings. More patients (64%) improved if younger than 75 years; for patients older than 75 years, only 11% of the patients improved. The Barthel index was higher (P < 0.05) in improved patients.
CONCLUSION
Patients with normal pressure hydrocephalus benefit from shunt surgery for at least 5 years. High mortality rate, comorbidity, and old age hamper good long-term outcome and emphasize the importance of patient selection.
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Affiliation(s)
- Babar Kahlon
- Department of Neurosurgery, University Hospital, Lund, Sweden.
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18
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Bech-Azeddine R, Høgh P, Juhler M, Gjerris F, Waldemar G. Idiopathic normal-pressure hydrocephalus: clinical comorbidity correlated with cerebral biopsy findings and outcome of cerebrospinal fluid shunting. J Neurol Neurosurg Psychiatry 2007; 78:157-61. [PMID: 17012342 PMCID: PMC2077673 DOI: 10.1136/jnnp.2006.095117] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To elucidate the importance of clinically diagnosed cerebral comorbidity in idiopathic normal-pressure hydrocephalus (INPH) and its effect on improvement after shunt surgery as well as concordance with parenchymal pathological changes described in frontal cerebral biopsy specimens. METHODS In 28 consecutive patients diagnosed with INPH and shunted according to clinical, radiological and cerebrospinal fluid dynamic criteria, concomitant disorders were carefully registered, with special emphasis on cerebrovascular disease (CVD) and possible Alzheimer's disease. During shunt surgery, a frontal cerebral biopsy specimen was obtained and subsequently analysed for pathological changes. RESULTS One or several concurrent disorders were present in 89% of the patients, most often CVD (n = 17) and possible Alzheimer's disease (n = 12), of which eight patients presented both, diagnosed according to the criteria of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association. The shunt success rate was 33%. A clear tendency towards increasing prevalence of CVD or Alzheimer's disease was found in the subgroups with no improvement or clinical deterioration compared with the patients improving after shunt surgery. The presence of CVD tended towards an unfavourable shunt outcome. The pathological parenchymal changes reflected the clinical diagnoses of comorbidity, and were described in about half of the biopsy specimens, with Alzheimer's disease (n = 7) and vascular changes (n = 7) being the most common findings. However, no significant correlation was found with the clinical diagnoses of Alzheimer's disease and CVD. The presence of cerebral comorbidity, whether diagnosed clinically or by brain biopsy, did not preclude clinical improvement after shunt operation. CONCLUSIONS A high prevalence of CVD and Alzheimer's disease was found in patients shunted for INPH, which was reflected, although less commonly, by similar neuropathological biopsy findings. No significant correlation was found between the presence of comorbidity and shunt outcome. The findings support the perception of INPH as a multiaetiological clinical entity, possibly overlapping pathophysiologically with CVD and Alzheimer's disease.
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Affiliation(s)
- R Bech-Azeddine
- The University Clinic of Neurosurgery, Rigshospitalet, Copenhagen, Denmark.
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19
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Eide PK, Brean A. Intracranial pulse pressure amplitude levels determined during preoperative assessment of subjects with possible idiopathic normal pressure hydrocephalus. Acta Neurochir (Wien) 2006; 148:1151-6; discussion 1156. [PMID: 17039303 DOI: 10.1007/s00701-006-0896-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2006] [Accepted: 08/03/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND It was previously reported that the intracranial pulse pressure amplitudes were elevated in idiopathic normal pressure hydrocephalus (iNPH) patients responding to shunt surgery. In this study, pulse pressure amplitudes were determined in all patients referred for tentative iNPH, and patients were selected for shunt surgery based on the determination of their threshold levels of intracranial pulse pressure amplitudes. PATIENTS AND METHODS All patients referred to our department for tentative iNPH during a 12 months time period were included. Using intracranial pressure (ICP) monitoring the intracranial pulse pressure amplitudes were determined as the mean wave amplitude in consecutive 6-seconds time windows. Intracranial pulse pressure amplitudes were defined as being elevated when the mean wave amplitudes were either >or=4 mmHg in >or=70%, >or=5 mmHg in >or=40% or >or=6 mmHg in >or=10% of the ICP recording time. Shunt treatment was offered to those with elevated mean wave amplitudes. Clinical state was assessed by using a NPH Grading Scale and the Stein-Langfitt scale before ICP monitoring, and then repeated after 12 months. RESULTS Among the 40 iNPH patients included during the 12 months period, the mean wave amplitudes were elevated in 24 patients (60%), while not being elevated in 16 (40%). Neither pre-operative clinical state, radiological ventricular size nor co-morbidity differed between patient groups with elevated or non-elevated mean wave amplitudes. In the shunted patients who had pre-operatively elevated mean wave amplitudes, 91% had very significant clinical change after 12 months (median change in NPH score +4). In those with non-elevated amplitudes and no shunt, clinical state was somewhat worse after 12 months (median change in NPH score -1). CONCLUSIONS In this one-year material, mean wave amplitudes were elevated in 60% of iNPH patients. In those with elevated mean wave amplitudes who were treated with shunt, 91% had a significant clinical response.
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Affiliation(s)
- P K Eide
- Department of Neurosurgery, The National Hospital, Rikshospitalet, Oslo, Norway.
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Allin DM, Czosnyka ZH, Czosnyka M, Richards HK, Pickard JD. In vitro hydrodynamic properties of the Miethke ProGAV hydrocephalus shunt. Cerebrospinal Fluid Res 2006; 3:9. [PMID: 16808836 PMCID: PMC1552084 DOI: 10.1186/1743-8454-3-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Accepted: 06/29/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Adjustable shunts are very popular in the management of hydrocephalus and are believed to help in minimizing the number of surgical revisions. The drawback with almost all constructions is that they may be accidentally readjusted in relatively weak magnetic fields (around 30-40 mTesla) MATERIALS AND METHODS The ProGav Miethke shunt is composed of an adjustable balloon-spring valve unit and an integrated over-drainage compensating gravitational device (known as the shunt assistant). A mechanical 'brake' is intended to prevent changes to the valve's performance level in a strong magnetic field. We evaluated the performance and hydrodynamic properties of a sample of three valves in the UK Shunt Evaluation Laboratory. RESULTS All the shunts showed good mechanical durability over the three-month period of testing, and good stability of hydrodynamic performance over a one-month period. The pressure-flow performance curves, operating, opening and closing pressures fell within the limits specified by the manufacturer, and changed according to the programmed performance levels. The operating pressure increased when the shunt assistant was in the vertical position, as specified. The valve has a low hydrodynamic resistance (0.53 mm mmHg ml(-1) min(-1)). External programming proved to be easy and reliable. Strong magnetic fields from a 3 Tesla MR scanner were not able to change the programming of the valve. CONCLUSION The ProGAV shunt is an adjustable, low resistance valve that is able to limit posture-related over-drainage. Unlike other adjustable valves, the ProGAV cannot be accidentally re-adjusted by external magnetic field such as a 3T MR scanner.
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Affiliation(s)
- David M Allin
- Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK
| | - Zofia H Czosnyka
- Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK
| | - Marek Czosnyka
- Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK
| | - Hugh K Richards
- Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK
| | - John D Pickard
- Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK
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Guendling K, Smielewski P, Czosnyka M, Lewis P, Nortje J, Timofeev I, Hutchinson PJ, Pickard JD. Use of ICM+ software for on-line analysis of intracranial and arterial pressures in head-injured patients. ACTA NEUROCHIRURGICA. SUPPLEMENT 2006; 96:108-13. [PMID: 16671436 DOI: 10.1007/3-211-30714-1_25] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
OBJECTIVE To summarize our experience from the first 2 years of use of the ICM+ software in our Neurocritical Care Unit (NCCU). MATERIALS AND METHODS Ninety-five head-injured patients (74 males, 21 females), average age 36 years, were managed in the NCCU. Intracranial pressure (ICP) was monitored using Codman intraparenchymal probes and arterial blood pressure (ABP) was measured from the radial artery. Signals were monitored by ICM+ software calculating mean values of ICP, ABP, cerebral perfusion pressure (CPP) and various indices describing pressure reactivity, compensation and vascular waveforms of ICP (pulse amplitude, respiratory, and slow waves), etc. RESULTS Mean ICP was 17 mmHg, mean CPP was 73 mmHg. Seven patients showed permanent disturbance of cerebral autoregulation (mean pressure reactivity index above 0.3). Pressure reactivity index demonstrated significant U-shape relationship with CPP, suggesting loss of pressure reactivity at too low (CPP < 55 mmHg) and too high CPPs (CPP > 95 mmHg). Mean ICP was inversely correlated with respiratory rate (R = 0.46; p < 0.0001; reciprocal model). CONCLUSION The new version of ICM+ software proved to be useful clinically in the NCCU. It allows continuous monitoring of pressure reactivity and exploratory analysis of factors implicating intracranial hypertension.
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Affiliation(s)
- K Guendling
- Academic Department of Clinical Neuroscience, Addenbrooke's Hospital, Cambridge, UK
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