title: Clinical testing of CSF circulation in hydrocephalus.
abstract: Recent 'NPH Dutch trial' has re-emphasised the importance of the resistance to cerebrospinal fluid (CSF) outflow (Rcsf) in the diagnosis of hydrocephalus. We re-evaluated the clinical utility of the physiological measurements revealing CSF dynamics. The results were summarized from our previous publications. The Computerised Infusion Test was designed to perform quick and low-invasive assessment of CSF dynamics described by parameters as Rcsf, brain compliance, elasticity coefficient, estimated sagittal sinus pressure, CSF formation rate and other variables. Overnight ICP monitoring with quantitative analysis of CSF dynamics was used in those cases where infusion study was unreliable or producing results close to the borderline. We found that the threshold of normal and increased Rcsf should be age-matched because in patients older than 55 Rcsf increases 0.2 mm Hg/(ml/min) per year (p < 0.04: N = 56). Rcsf was positively correlated with cerebral autoregulation (R = 0.41; p < 0.03; N = 36) indicating that in patients with symptoms of NPH but normal Rcsf underlying cerebrovascular disease is more frequent. Computerized infusion tests and overnight ICP monitoring are useful diagnostic technique alone or in conjunction with other forms of physiological measurement.
authors.affiliation: Academic Neurosurgical Unit, Department of Neurosciences, Addenbrooke's Hospital, Cambridge, UK. zc200@medschl.cam.ac.uk
authors.forename: Z
authors.initials: Z
authors.lastname: Czosnyka
authors.forename: M
authors.initials: M
authors.lastname: Czosnyka
authors.forename: B
authors.initials: B
authors.lastname: Owler
authors.forename: S
authors.initials: S
authors.lastname: Momjian
authors.forename: M
authors.initials: M
authors.lastname: Kasprowicz
authors.forename: E A
authors.initials: EA
authors.lastname: Schmidt
authors.forename: P
authors.initials: P
authors.lastname: Smielewski
authors.forename: J D
authors.initials: JD
authors.lastname: Pickard
mesh_terms: D002557:Cerebrospinal Fluid Shunts; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D006801:Humans; D006849:Hydrocephalus / Q000134:cerebrospinal fluid* / Q000175:diagnosis* / Q000601:surgery; D007427:Intracranial Pressure; D008365:Manometry / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity