Purchase this article with an account.
Ningli Wang, Zheng Zhang, Jost Jonas, Robert Ritch, Beijing Intracranial and Intraocular Pressure (iCOP) Study; Valsalva Maneuver, Intraocular Pressure, Cerebrospinal Fluid Pressure, and Optic Disc Topography: Beijing Intracranial and Intraocular Pressure (iCOP) Study. Invest. Ophthalmol. Vis. Sci. 2013;54(15):63. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To assess whether a Valsalva maneuver influences intraocular pressure (IOP), cerebrospinal fluid pressure (CSF-P) and, by a change in the trans-laminar cribrosa pressure difference, optic nerve head morphology.
The study included 20 neurological patients who required lumbar puncture and 20 healthy volunteers. In a first study part, neurological patients underwent measurement of IOP and lumbar CSF-P measurement in a lying position before and during a Valsalva maneuver with a documented continuous expiratory pressure of ≥30 mmHg for about 20 seconds. In the second part, 20 healthy subjects underwent ocular tonometry and confocal scanning laser tomography of the optic nerve head before and during a Valsalva maneuver.
During the Valsalva maneuver in the first study part, 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 maneuver in the second part, IOP increased by 4.5±4.2 mmHg and optic cup volume (P<0.001), cup/disc area ratio (P=0.04), cup/disc diameter ratio (P=0.03) and maximum optic cup depth (P=0.02) significantly decreased, while neuroretinal rim volume (P=0.003) and mean retinal nerve fiber layer thickness (P=0.02) significantly increased.
The Valsalva maneuver-associated increase in CSF-P was significantly larger than, and not correlated with, and a simultaneous increase in IOP. This Valsalva maneuver associated reversal of the trans-lamina cribrosa pressure difference resulted in a change of the three-dimensional optic nerve head morphology with a decrease in optic cup related parameters and an enlargement of neuroretinal rim related parameters. These findings may be relevant to the pathogenesis of glaucomatous optic neuropathy.
This PDF is available to Subscribers Only