Ophthalmological applications

For the use of perfluorocarbon molecules for ophthalmologic applications, see also in this volume the chapter by D. Menz and J.H. Dresp. 

In ophthalmological application, this characteristic of the PFCLs is not used yet. In general, the products used are air equilibrated with the consequence that the oxygen partial pressure in the eye is increased from 15 Torr to 160 Torr and the CO2 partial pressure drops down from 50 Torr to 3 Torr initially. These differences are equilibrated intra-ocularly by diffusion processes, but the initial difference to the physiological level of gas concentration activates the constriction of the retinal vessels, resulting in an increase of the blood flow. In rabbit eyes, a damage of the retina could be attributed to this mechanism [38,39], On the other hand, endotamponade media with controlled levels of dissolved gases could not only avoid such a scenario but should also be useable for a therapeutic manipulation of the retinal perfusion. 

I. Lattes, B. Feurer, B. Guidetti, V. Payrou, Fluorinated organic compounds, ophthalmological applications thereof and method for making same, US Patent No. 

The microemulsions containing pilocarpine were formulated using lecithin, propylene glycol, and PEG 200 as co-surfactant and isopropyl myristate as the oil phase. The formulations were of low viscosity with a refractive index lending to ophthalmologic applications. ... 

Another ophthalmologic application of polymeric prostheses is the artificial cornea or keratoprosthesis. This device has been developed for more than a century, starting with the work of Heusser who was the first to implant artificial corneas in patients in 1859 [189], However, it was not until after World War II that researchers noticed that PMMA particles were well tolerated in patient eyes [190]. Ever since, other polymeric materials such as nylon, PU, and PTFE... 

Another ophthalmologic application of polymeric biomaterials is the development of ocular prosthesis and biologically inspired compound eyes [197,198]. Such prostheses, commonly fabricated from porous polyethylene, are designed to serve as nonfunctional artificial substitutes for enucleated eyeballs [199]. 

Optical properties are especially important for polymers used in ophthalmologic applications. Optical clarity is, of course, critical for applications such as contact lenses, artificial... 

The history of biomaterials in ophthalmological applications spans over 150 years and has been eloquently documented by Chirila in his recent book. The latter covers a range of topics from intraocular lenses to different ophthalmological TE applications. One conclusion on reading this work is that some remarkable commercial successes are evident in this particular field. 

The cytotoxicity of MPC-based eye drops containing 0.1% Lipidure-PMB (a copolymer of MPC and butyl methacrylate NOF Corp.) was examined and it was found to have similar nontoxicity to other clinically approved artificial tear products. " From these literature reports it appears that the unique properties and nontoxicity of MPC are ideal for ophthalmological applications. 

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