Assessment of cerebrospinal fluid outflow conductance using an adaptive observer--experimental and clinical evaluation.


:Idiopathic normal pressure hydrocephalus (INPH) patients have a disturbance in the dynamics of the cerebrospinal fluid (CSF) system. The outflow conductance, C, of the CSF system has been suggested to be prognostic for positive outcome after treatment with a CSF shunt. All current methods for estimation of C have drawbacks; these include lack of information on the accuracy and relatively long investigation times. Thus, there is a need for improved methods. To accomplish this, the theoretical framework for a new adaptive observer (OBS) was developed which provides real-time estimation of C. The aim of this study was to evaluate the OBS method and to compare it with the constant pressure infusion (CPI) method. The OBS method was applied to data from infusion investigations performed with the CPI method. These consisted of repeated measurements on an experimental set-up and 30 patients with suspected INPH. There was no significant difference in C between the CPI and the OBS method for the experimental set-up. For the patients there was a significant difference, -0.84+/-1.25 microl (s kPa)(-1), mean +/- SD (paired sample t-test, p<0.05). However, such a difference is within clinically acceptable limits. This encourages further development of this new real-time approach for estimation of the outflow conductance.


Physiol Meas


Andersson K,Manchester IR,Andersson N,Shiriaev A,Malm J,Eklund A




Has Abstract


2007-11-01 00:00:00














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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Rozman J,Zorko B,Bunc M,Mikac U,Tegou E

    更新日期:2002-11-01 00:00:00

  • Circuit modeling of the electrical impedance: II. Normal subjects and system reproducibility.

    abstract::Part I of this series showed that the five-element circuit model accurately mimics impedances measured using multi-frequency electrical impedance myography (MFEIM), focusing on changes brought on by disease. This paper addresses two requirements which must be met if the method is to qualify for clinical use. First, th...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Shiffman CA,Rutkove SB

    更新日期:2013-02-01 00:00:00

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Weiss A,Herman T,Plotnik M,Brozgol M,Giladi N,Hausdorff JM

    更新日期:2011-12-01 00:00:00

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    journal_title:Physiological measurement

    pub_type: 杂志文章,随机对照试验


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    更新日期:2018-04-20 00:00:00

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    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Tarvainen MP,Georgiadis SD,Ranta-Aho PO,Karjalainen PA

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    authors: Minhas JS,Syed NF,Haunton VJ,Panerai RB,Robinson TG,Mistri AK

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    pub_type: 杂志文章


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    pub_type: 临床试验,杂志文章,随机对照试验


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    pub_type: 杂志文章


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    pub_type: 杂志文章


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    pub_type: 杂志文章


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    pub_type: 临床试验,杂志文章


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    pub_type: 临床试验,杂志文章


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    pub_type: 杂志文章


    authors: Benalcazar-Parra C,Garcia-Casado J,Ye-Lin Y,Alberola-Rubio J,Lopez Á,Perales-Marin A,Prats-Boluda G

    更新日期:2019-09-03 00:00:00