Breakdown of Viscoelastic Substances

Following Healon s introduction into the market, ophthalmic viscosurgical devices (OVD) experienced both a rapid spread and modification as manufacturers developed an array of substances with diverse formulations. 

At the moment, the variety of new viscoelastic preparations is vast and therefore, varies extensively from place to place (Fig. 1). 

Based on our own study results, we propose a partial revision of the viscoelastic substance grouping/classification proposed by Arshinoff, to be based on the rheologic and physicochemical characteristics of viscoelastic substances obtained in cooperation with the Max-Planck Institute for Polymer Research, Department of Rheology, in Mainz, Germany. Furthermore, a new product, the so-called viscous cohesion dissociated high molecular weight viscoelastic , better known by its product name, Healon 5 (Fig. 2), is now at our disposal. Healon 5 is formulated to fulfill specific requirements for use in phacoemulsification (i.e., with both cohesive and dispersive characteristics). 

Af = million, K = thousand HA = sodium hyaluronate, CS = chondroilin sulfate HPMC= hydroxy-propyl met hyl cel I u lose 

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