title: Quantitative evaluation of changes in gait after extended cerebrospinal fluid drainage for normal pressure hydrocephalus.
abstract: Idiopathic normal pressure hydrocephalus (iNPH) is characterized by gait instability, urinary incontinence and cognitive dysfunction. These symptoms can be relieved by cerebrospinal fluid (CSF) drainage, but the time course and nature of the improvements are poorly characterized. Attempts to prospectively identify iNPH patients responsive to CSF drainage by evaluating presenting gait quality or via extended lumbar cerebrospinal fluid drainage (eLCD) trials are common, but the reliability of such approaches is unclear. Here we combine eLCD trials with computerized quantitative gait measurements to predict shunt responsiveness in patients undergoing evaluation for possible iNPH. In this prospective cohort study, 50 patients presenting with enlarged cerebral ventricles and gait, urinary, and/or cognitive difficulties were evaluated for iNPH using a computerized gait analysis system during a 3day trial of eLCD. Gait speed, stride length, cadence, and the Timed Up and Go test were quantified before and during eLCD. Qualitative assessments of incontinence and cognition were obtained throughout the eLCD trial. Patients who improved after eLCD underwent ventriculoperitoneal shunt placement, and symptoms were reassessed serially over the next 3 to 15months. There was no significant difference in presenting gait characteristics between patients who improved after drainage and those who did not. Gait improvement was not observed until 2 or more days of continuous drainage in most cases. Symptoms improved after eLCD in 60% of patients, and all patients who improved after eLCD also improved after shunt placement. The degree of improvement after eLCD correlated closely with that observed after shunt placement.
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
authors.forename: Felix
authors.initials: F
authors.lastname: Yang
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
authors.forename: Thu-Trang
authors.initials: TT
authors.lastname: Hickman
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA; Department of Rehabilitation Services, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Megan
authors.initials: M
authors.lastname: Tinl
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA; Department of Rehabilitation Services, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Iracheta
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA; Department of Rehabilitation Services, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Grace
authors.initials: G
authors.lastname: Chen
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA; Department of Rehabilitation Services, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Flynn
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Shuman
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
authors.forename: Tatyana A
authors.initials: TA
authors.lastname: Johnson
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
authors.forename: Rebecca R
authors.initials: RR
authors.lastname: Rice
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
authors.forename: Isaac M
authors.initials: IM
authors.lastname: Rice
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Wiemann
authors.affiliation: Adult Hydrocephalus Program, Department of Neurosurgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA. Electronic address: mjohnson27@partners.org.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Johnson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D020233:Gait Disorders, Neurologic / Q000209:etiology / Q000601:surgery*; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000150:complications / Q000601:surgery*; D008297:Male; D017063:Outcome Assessment, Health Care / Q000379:methods*; D017287:Ventriculoperitoneal Shunt / Q000379:methods*
keywords: CSF; Gait; Normal pressure hydrocephalus; Ventriculoperitoneal shunt