Intraocular pressure vs intracranial pressure in disease conditions: A prospective cohort study (Beijing iCOP study)

BACKGROUND The correlation between intracranial pressure (ICP) and intraocular pressure (IOP) is still controversial in literature and hence whether IOP can be used as a non-invasive surrogate of ICP remains unknown. The aim of the current study was to further clarify the potential correlation between ICP and IOP. METHODS The IOP measured with Goldmann applanation tonometer was carried out on 130 patients whose ICP was determined via lumber puncture. The Pearson correlation coefficient between ICP and IOP was calculated, the fisher line discriminated analysis to evaluate the effectivity of using IOP to predict the ICP level. RESULTS A significant correlation between ICP and IOP was found. ICP was correlated significantly with IOP of the right eyes (p < 0.001) and IOP of the left eyes (p = 0.001) and mean IOP of both eyes (p < 0.001), respectively. However, using IOP as a measurement to predict ICP, the accuracy rate was found to be 65.4%. CONCLUSION Our data suggested that although a significant correlation exists between ICP and IOP, caution needs to be taken when using IOP readings by Goldmann applanation tonometer as a surrogate for direct cerebrospinal fluid pressure measurement of ICP.