methylcellulose and Corneal-Injuries

Topics: Anesthesia, General; Bandages; Cornea; Corneal Injuries; Double-Blind Method; Eye Injuries; Humans; Intraoperative Complications; Methylcellulose; Ointment Bases; Ointments; Ophthalmic Solutions; Paraffin; Pharmaceutic Aids

Most formulations of artificial tears include high-molecular weight hydrophilic polymers (hydrogels) that are usually thought to serve to enhance viscosity and to act as demulcents. A few reports have indicated that application of some of the polymers accelerates healing of wounds in epithelia. Since activation of the epidermal growth factor (EGF) receptor is critical for spontaneous corneal epithelial wound healing, we tested commonly used hydrogels for their ability to activate the EGF receptor and enhance closure of wounds. Five structurally unrelated hydrogels used in artificial tears were found to activate the EGF receptor. Importantly, two of the hydrogels enhanced wound healing in an organ culture model. We propose that the efficacy of hydrogels in treating dry eye may be related to their ability to activate the EGF receptor, and that hydrogels are inexpensive, safe agents to promote healing of wounds in the cornea and possibly in other tissues.

Topics: Animals; Cell Line; Cornea; Corneal Injuries; Dose-Response Relationship, Drug; ErbB Receptors; Humans; Hydrogels; Limbus Corneae; Methylcellulose; Ophthalmic Solutions; Organ Culture Techniques; Rabbits; Wound Healing

Since 1976 I have used a solution of hydroxypropyl methylcellulose to prevent corneal endothelial damage during intraocular lens implantation. The substance is inexpensive, readily available, and can be easily dissolved. This paper describes preparation of a 2% solution.

Topics: Corneal Injuries; Eye Injuries; Humans; Hypromellose Derivatives; Lenses, Intraocular; Methods; Methylcellulose; Osmolar Concentration; Solutions

Sodium hyaluronate (Healon), chondroitin sulfate, and methylcellulose have been used to protect the corneal endothelium from intraocular lens trauma. A study of the efficacy and toxicity of these compounds showed that 1% sodium hyaluronate, 0.4% methylcellulose, and 20% chondroitin sulfate were nontoxic to the corneal endothelium, but that 20% chondroitin sulfate caused a marked decrease in corneal thickness because of its hypertonicity. Anterior chamber injection of these viscous substances resulted in an increase in intraocular pressure. Within one to four hours the maximum intraocular pressure with 1% sodium hyaluronate was 67 +/- 4.1 mm Hg and that with 20% chondroitin sulfate was 55 +/- 3.5 mm Hg. The intraocular pressure did not increase to these high levels with 10% chondroitin sulfate or 0.4% methylcellulose or when the test substances were washed out of the anterior chamber. The corneal endothelium was protected from injury with 1% sodium hyaluronate and 20% chondroitin sulfate, but 10% chondroitin sulfate and 0.4% methylcellulose provided only minimal protection.

Topics: Animals; Chondroitin; Chondroitin Sulfates; Cornea; Corneal Injuries; Endothelium; Hyaluronic Acid; Intraocular Pressure; Lenses, Intraocular; Methylcellulose; Rabbits

In 221 consecutive cataract extractions the peroperative epithelial damage was assessed by vital staining with 1% lissamine green, using logarithmic grading (grade 5 more than 10 000 stained dots) on cornea and on the superior, medial, lateral, and inferior conjunctiva. Evenly spread dots were seen on the cornea in 63 per cent of the eyes not subjected to protective treatment. In 35 per cent we observed staining caused by taut suturing of cornea and/or conjunctiva, in 10 per cent horizontal lines due to corneal bending during the extraction. The cornea was protected most effectively by healon (1% instilled once). Saline (4 or 5 instillations during the operation sufficed) protected equally well as gelatin sponge, methylcellulose, polyvinyl alcohol, and a soft contact lens. The inferior conjunctiva was protected only by healon, the superior also by saline, gelatin sponge, and polyvinyl alcohol.

Topics: Adult; Aged; Cataract Extraction; Conjunctiva; Contact Lenses, Hydrophilic; Cornea; Corneal Injuries; Female; Gelatin Sponge, Absorbable; Humans; Hyaluronic Acid; Lissamine Green Dyes; Male; Methylcellulose; Middle Aged; Polyvinyl Alcohol; Sodium Chloride

Topics: Corneal Injuries; Eye Injuries; Humans; Lenses, Intraocular; Methylcellulose