Ocular rigidity assessment in the decision making for glaucoma patients

Abstract

AbstractPurpose So far there have been controversial reports concerning ocular rigidity in glaucomatous eyes, ranging from reduced values (which may rise following treatment with b‐blockers or pilocarpine), to increased values, compared with non‐glaucomatous eyes. Ocular rigidity may play an important role in glaucoma pathogenesis, since it determines ocular wall changes in response to pressure changes and thus affects the anatomical course of optic nerve fibers as well as the local vascular autoregulation. Despite the importance of ocular rigidity in glaucoma pathogenesis, its role in the clinical practice has so far been compromised, mainly due to the difficulties in the accurate calculation of a rigidity coefficient in vivo. The traditional approach to ocular rigidity calculation by differential tonometry and insertion of readings into Friedenwald’s chart has received criticism, mainly because Friedenwald’s nomogram was based on data from cadaveric eyes, which may display significantly altered rigidity values, compared with living eyes.Methods Related literature review.Results Recent developments, such as the manometric in vivo calculation of a rigidity coefficient, the determination of ocular elasticity through ultrasound elastography and the differential tonometry between applanation and dynamic contour tonometers may enable a minimally invasive and reliable assessment of ocular rigidity values for living eyes.Conclusion The possibility to reliably calculate ocular rigidity in vivo using non‐invasive or minimally invasive methods could lead to the incorporation of rigidity in the decision making process for glaucoma patients.