Diagnostic accuracy of intraocular pressure measurement for the detection of raised intracranial pressure: meta-analysis

Abstract

Object Because clinical examination and imaging may be unreliable indicators of intracranial hypertension, intraocular pressure (IOP) measurement has been proposed as a noninvasive method of diagnosis. The authors conducted a systematic review and meta-analysis to determine the correlation between IOP and intracranial pressure (ICP) and the diagnostic accuracy of IOP measurement for detection of intracranial hypertension. Methods The authors searched bibliographic databases (Ovid MEDLINE, Ovid EMBASE, and the Cochrane Central Register of Controlled Trials) from 1950 to March 2013, references of included studies, and conference abstracts for studies comparing IOP and invasive ICP measurement. Two independent reviewers screened abstracts, reviewed full-text articles, and extracted data. Correlation coefficients, sensitivity, specificity, and positive and negative likelihood ratios were calculated using DerSimonian and Laird methods and bivariate random effects models. The I2 statistic was used as a measure of heterogeneity. Results Among 355 identified citations, 12 studies that enrolled 546 patients were included in the meta-analysis. The pooled correlation coefficient between IOP and ICP was 0.44 (95% CI 0.26–0.63, I2 = 97.7%, p < 0.001). The summary sensitivity and specificity for IOP for diagnosing intracranial hypertension were 81% (95% CI 26%–98%, I2 = 95.2%, p < 0.01) and 95% (95% CI 43%–100%, I2 = 97.7%, p < 0.01), respectively. The summary positive and negative likelihood ratios were 14.8 (95% CI 0.5–417.7) and 0.2 (95% CI 0.02–1.7), respectively. When ICP and IOP measurements were taken within 1 hour of another, correlation between the measures improved. Conclusions Although a modest aggregate correlation was found between IOP and ICP, the pooled diagnostic accuracy suggests that IOP measurement may be of clinical utility in the detection of intracranial hypertension. Given the significant heterogeneity between included studies, further investigation is required prior to the adoption of IOP in the evaluation of intracranial hypertension into routine practice.

Pressure balance and imbalance in the optic nerve chamber: The Beijing Intracranial and Intraocular Pressure (iCOP) Study

“…Some investigators have argued that IOP is correlated with ICP (Lashutka et al, 2004;Li et al, 2012), but others argue that they are unrelated (Czarnik et al, 2009;Kirk et al, 2011). Still others have concluded that, although there is a correlation between ICP and IOP, IOP is a "poor predictor" of ICP (Golan et al, 2013;Spentzas et al, 2010;Yavin et al, 2014). Our study answers this question and shows that all authors are partially correct.…”

Spaceflight-Induced Intracranial Hypertension and Visual Impairment: Pathophysiology and Countermeasures

“…These features included dilation of the optic nerve sheath, "bulging" of the terminal optic sheath subarachnoid space into the posterior aspect of the globe at the ONH, and a depressed perfusion of the optic disk/nerve junction. A positive correlation between ICP and IOP is found in some clinical studies, and hence, IOP is proposed as a noninvasive measure of ICP for clinical utility (214), but it seems to lack the accuracy necessary for close management of intracranial pressure in emergency medicine (267,306).…”

The Increase of Intra-Abdominal Pressure Can Affect Intraocular Pressure

“…It has been reported that intrathoracic pressure, intracerebral pressure [ 4 , 5 ], and intraocular pressure [ 6 , 7 ] increase when IAP increases. Nevertheless, it is known that increased intracranial pressure would affect intraocular pressure [ 8 ]. However, there have not been adequate studies about the relationship between IAP and IOP.…”