Intraocular pressure (IOP) measurement is the cornerstone of the management of glaucoma patients. The gold standard for assessing IOP is Goldmann applanation tonometry (GAT). Recently, the dynamic contour tonometer (DCT) has become available. While both devices provide reliable IOP measurements, the results are not interchangeable. DCT has the advantage of measuring an additional parameter: ocular pulse amplitude (OPA). OPA is defined as the difference between systolic and diastolic IOP and represents the pulsatile wave front produced by the varying amount of blood in the eye during the cardiac cycle. It has been shown to vary with ocular structural parameters, such as axial length, corneal thickness, and ocular rigidity, as well as with systemic variables like heart rate, blood pressure, and left ventricular ejection fraction. Although the existence of some of these associations is still controversial, the clinical relevance of OPA has been consistently suggested, especially in glaucoma. Further research on this intriguing parameter could not only provide insight into glaucoma pathophysiology but also help integrate this variable into clinical practice.

Keywords:
Intraocular pressure, Glaucoma, Dynamic contour tomography
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2015
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