I would like to congratulate Theelen et al for their recent article on impact factors on intraocular pressure measurements in healthy subjects,¹ and I would like to add a thought. As Theelen and colleagues point out with reference to the literature,^2,3 increased pressure in the jugular vein leads to increased brain pressure, and by an increase in the episcleral venous pressure, to an elevation of intraocular pressure. Correspondingly, …