Correlation between ocular perfusion pressure and translaminar pressure difference in glaucoma: Evidence for a three-pressure disease?

Aim: To evaluate the correlation between the translaminar pressure difference (TLPD) and the ocular perfusion pressure (OPP) in glaucoma patients. Methods: This was a cross-sectional study. Primary open-angle glaucoma (POAG) patients and normal individuals underwent an ophthalmic evaluation as well as blood pressure, height, and weight measurements. Intracranial pressure (ICP) and OPP were calculated using proxy mathematical formulas to attain indirect surrogate parameter values. The TLPD was calculated as intraocular pressure minus ICP. The association between the variables was evaluated using linear and non-linear regression analysis and the correlation estimated with Pearson’s correlation coefficient. Results: The sample included 50 POAG patients and 25 normal subjects. The mean OPP for all 75 subjects (75 eyes) was 53.1 ± 9.3 mmHg and the calculated TLPG was 3.1 ± 4.2 mmHg. TLPG showed a negative correlation with OPP (r = −0.580; 95% CI, −0.690 to −0.366; p