title: Valsalva manoeuver, intra-ocular pressure, cerebrospinal fluid pressure, optic disc topography: Beijing intracranial and intra-ocular pressure study.
abstract: OBJECTIVE
  To assess whether a Valsalva manoeuver influences intra-ocular pressure (IOP), cerebrospinal fluid pressure (CSF-P) and, by a change in the trans-laminar cribrosa pressure difference, optic nerve head morphology.
  
  
  METHODS
  In the first part of the study, 20 neurological patients (study group 'A') underwent measurement of IOP and lumbar CSF-P measurement in a lying position before and during a Valsalva manoeuver. In the second study part, 20 healthy subjects (study group 'B') underwent ocular tonometry and confocal scanning laser tomography of the optic nerve head before and during a Valsalva manoeuver.
  
  
  RESULTS
  During the Valsalva manoeuver in study group 'A', the increase in CSF-P by 10.5 ± 2.7 mmHg was significantly (p < 0.001) higher than the increase in IOP by 1.9 ± 2.4 mmHg. The change in CSF-P was not significantly (p = 0.61) correlated with the change in IOP. During the Valsalva manoeuver in study group 'B', IOP increased by 4.5 ± 4.2 mmHg and optic cup volume (p < 0.001), cup/disc area ratio (p = 0.02), cup/disc diameter ratio (p = 0.03) and maximum optic cup depth (p = 0.01) significantly decreased, while neuroretinal rim volume (p = 0.005) and mean retinal nerve fibre layer thickness (p = 0.02) significantly increased.
  
  
  CONCLUSIONS
  The Valsalva manoeuver-associated short-term increase in CSF-P was significantly larger than a simultaneous short-term increase in IOP. It led to a Valsalva manoeuver-associated decrease or reversal of the trans-laminar cribrosa pressure difference, which was associated with a change in the three-dimensional optic nerve head morphology: optic cup-related parameters decreased and neuroretinal rim-related parameters enlarged. These findings may be of interest for the pathogenesis of glaucomatous optic neuropathy.
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zhang
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Wang
authors.forename: Jost B
authors.initials: JB
authors.lastname: Jonas
authors.forename: Huaizhou
authors.initials: H
authors.lastname: Wang
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Zhang
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Peng
authors.forename: Robert
authors.initials: R
authors.lastname: Ritch
authors.forename: Guohong
authors.initials: G
authors.lastname: Tian
authors.forename: Diya
authors.initials: D
authors.lastname: Yang
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Junfa
authors.initials: J
authors.lastname: Li
authors.forename: Ningli
authors.initials: N
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D015170:Cerebrospinal Fluid Pressure / Q000502:physiology*; D002681:China; D005260:Female; D005902:Glaucoma, Open-Angle / Q000503:physiopathology*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000503:physiopathology*; D014065:Tonometry, Ocular; D014636:Valsalva Maneuver / Q000502:physiology*; D055815:Young Adult
keywords: Valsalva manoeuver; cerebrospinal fluid pressure; heidelberg retina tomograph; intra-ocular pressure; open-angle glaucoma; trans-laminar cribrosa pressure difference