chondroitin-sulfates and Eye-Injuries

Solutions of flexible macromolecules are used in ophthalmic surgery for insertion of intraocular lens, during corneal transplantation, in cataract, corneal, glaucoma, trauma, and vitreo-retinal surgery. Polymeric materials used in formulating these solutions include hyaluronic acid, chondroitin sulfate, polyacrylamide, collagen, and mixtures of some of these materials. Although the physical properties of these materials have been studied extensively, the long-term effects resulting from transitory increases in intraocular pressure and loss of even a small number of corneal endothelial cells are still unknown. The purpose of this paper is to review the literature that is available on these topics.

Topics: Acrylic Resins; Animals; Biocompatible Materials; Chondroitin Sulfates; Collagen; Eye Injuries; Hyaluronic Acid; Intraocular Pressure; Methylcellulose; Ophthalmologic Surgical Procedures; Rheology; Time Factors; Viscosity

Traumatic periocular injuries occasionally result in significant soft tissue loss, for which there are limited management options that provide satisfactory cosmetic and functional outcomes. The authors describe the use of a bioengineered dermal substitute (Integra® Dermal Regeneration Template [DRT], Integra LifeSciences, Plainsboro, NJ) as an alternative to immediate flap reconstruction or skin grafting.. Retrospective interventional case series of patients who underwent DRT placement for periocular tissue loss at the time of trauma. In each case, primary closure or immediate flap reconstruction was deemed impractical or undesirable due to the size and location of the primary and associated secondary defects. One to four weeks later, the outer silicone layer was removed and healing assessed. Additional reconstructive techniques were performed as needed.. Three patients were treated at Bascom Palmer Eye Institute and one at Byers Eye Institute at Stanford. The defects healed completely in two patients, and by 79.2% in a third, with no need for additional reconstructive surgery. In the remaining patient, the defect was significantly downsized by 56.1%, allowing for a simpler flap reconstruction.. Bioengineered dermal substitutes should be considered as a viable alternative to traditional reconstructive techniques for large periocular defects resulting from trauma. The outer silicone layer prevents desiccation and serves as a protective barrier, while the inner collagen matrix organizes the growth of neo-dermis and minimizes wound contraction. The dimensions of cutaneous defects can therefore be reduced dramatically, potentially eliminating the need for skin grafting and/or reducing the ultimate complexity of flap reconstruction.

Topics: Accidents, Traffic; Adult; Aged; Chondroitin Sulfates; Collagen; Eye Injuries; Eyelids; Female; Humans; Male; Orbit; Plastic Surgery Procedures; Retrospective Studies; Skin; Skin, Artificial; Soft Tissue Injuries; Tissue Engineering; Wounds, Gunshot

We report the first use of the Integra Bilayer Matrix Wound Dressing (Integra LifeSciences Corp), a collagen sheet with glycosaminoglycans and a silicone layer, in an innovative reconstruction approach to devastating traumatic tissue loss in the periocular area. A 36-year-old woman was involved in a motor vehicle crash with a resultant large defect from the medial canthus to the temporal fossa and from the pretarsal skin to the brow. There was denudation of skin and soft tissue to the bone at the superolateral orbital apex. The severity of tissue loss precluded placement of an autograft or allograft; thus, a skin substitute was instead used, with a successful reconstructive outcome. Application of the newer bioengineered skin products for full-thickness skin wounds should be considered for reconstruction of the periocular area.

Topics: Accidents, Traffic; Adult; Chondroitin Sulfates; Collagen; Eye Injuries; Eyelids; Female; Humans; Orbit; Plastic Surgery Procedures; Polypropylenes; Skin Transplantation; Soft Tissue Injuries; Suture Techniques; Sutures; Transplantation, Autologous; Wound Healing; Zygomatic Fractures

The use of dispersive ophthalmic viscosurgical devices (OVDs) has been shown to provide significant protection against air bubble damage to the corneal endothelium when compared with cohesive OVDs. We compared the corneal endothelial protective effects of a new dispersive OVD, Healon-D, with Viscoat.. Healon-D and Viscoat were used in a randomized and masked fashion in the anterior chamber of 40 rabbit eyes during a procedure where ultrasound at 70% continuous energy was delivered for 2 min. Two millilitres of air bubbles were injected into the anterior chamber during the first minute of the procedure on each eye. Corneas were then stained with trypan blue and alizarin red and evaluated via light microscopy for endothelial injury. Both denuding of the endothelial layer, as well as damage to endothelial cells were quantified by using the Evaluation of Posterior Capsule Opacification digital imaging system.. The denuded area for eyes treated with Healon-D and Viscoat were not significantly different (medians of 0.004167and 0.003333, respectively, P = 0.8908). There was no significant difference in the area of endothelial cell damaged (medians of 0.02183 and 0.01433, respectively, P = 0.4565). When the denuded and damaged areas were calculated together, there was also no difference in the total injured area (medians of 0.05817 and 0.05821, respectively, P = 0.5740).. The new dispersive OVD Healon-D is equally as effective as Viscoat in protecting the corneal endothelial layer from denuding and damage from air bubbles during anterior segment surgery.

Topics: Animals; Anterior Chamber; Chondroitin; Chondroitin Sulfates; Drug Combinations; Endothelium, Corneal; Eye Injuries; Hyaluronic Acid; Phacoemulsification; Rabbits; Viscoelastic Substances

Topics: Chondroitin; Chondroitin Sulfates; Drug Combinations; Eye Injuries; Humans; Hyaluronic Acid; Intraoperative Complications; Lens Capsule, Crystalline; Phacoemulsification; Rupture

To evaluate the usefulness of viscoelastic in protecting the corneal endothelium from desiccation injury associated with fluid-air exchange in a rabbit model.. Experimental study.. Rabbit eyes undergoing pars plana lensectomy and vitrectomy were insufflated with either dry or humidified air for 20 minutes following introduction of either Opegan (sodium hyaluronate 1.0%; Santen, Osaka, Japan) or Viscoat (sodium hyaluronate 3%-chondroitin sulfate 4%; Alcon, Tokyo, Japan) into the anterior chamber. In two other groups of rabbit eyes, the same procedure was performed without using any viscoelastic agent. Corneas obtained from rabbits undergoing surgery were compared with corneas obtained from rabbits not undergoing surgery. Potential alterations in the corneal endothelium were investigated by scanning electron microscopy, by Phalloidin-FITC staining of actin and by in vitro measurements of corneal permeability for carboxyfluorescein using a diffusion chamber.. Scanning electron microscopy displayed less distortion of corneal endothelium with Opegan and Viscoat compared with the dry air-only exposed corneas. Using humidified air in Opegan and Viscoat coated corneas maintained the normal actin cytoskeleton during fluid-air exchange. Paracellular leakage was much less with Opegan and Viscoat use following infusion of dry air comparing to that of dry air-only group (P =.026 and P =.041). The difference was much more striking following humidified air infusion in Opegan or Viscoat coated corneas comparing to dry air-only infused corneas (P <.002 and P <.002).. Coating of rabbit corneal endothelium with Opegan or Viscoat before fluid-air exchange largely prevents dry air damage to the endothelium. Infusion of humidified air further protects corneal endothelium during fluid-air exchange in aphakic rabbit eyes.

Topics: Actins; Air; Animals; Chondroitin; Chondroitin Sulfates; Desiccation; Drug Combinations; Endothelium, Corneal; Eye Injuries; Fluoresceins; Humidity; Hyaluronic Acid; Lens, Crystalline; Microscopy, Electron, Scanning; Permeability; Rabbits; Vitrectomy

To determine whether viscoelastic materials effectively protect the corneal endothelium from air bubbles.. Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea.. Human eye-bank and rabbit eyes had a standardized phacoemulsification procedure with or without viscoelastic material (Healon [sodium hyaluronate 1.0%], Healon GV [sodium hyaluronate 1.4%], or Viscoat [chondroitin sulfate 4.0%-sodium hyaluronate 3.0%]). The integrity of the endothelium was examined after the procedure with F-actin staining and scanning electron microscopy. Rabbit eyes with and without viscoelastic material (Healon or Viscoat) had a standardized irrigation/aspiration (I/A) procedure. The mucinous layer of the endothelium was examined after the procedure with transmission electron microscopy.. In the phacoemulsification experiment without viscoelastic material, with Healon, and with Healon GV, the endothelium of human and rabbit corneas had many areas of cell loss in a pattern consistent with air-bubble damage. With Viscoat, endothelial cells remained intact. In the I/A experiment, the mucinous layer of Viscoat-exposed rabbit endothelium appeared thinner. In the same experiments without viscoelastic material or with Healon, the mucinous layer of the endothelium appeared normal.. Viscoat effectively protected the endothelium from air-bubble damage. Viscoat appears to protect the endothelium by acting as a physical barrier. Its adherence is probably related to the way it interacts with the mucinous layer of the endothelium.

Topics: Actins; Adolescent; Adult; Air; Animals; Child; Chondroitin; Chondroitin Sulfates; Drug Combinations; Endothelium, Corneal; Eye Injuries; Humans; Hyaluronic Acid; Microscopy, Electron, Scanning; Middle Aged; Phacoemulsification; Rabbits

The authors' study of the viscosities of various concentrations of sodium hyaluronate, chondroitin sulfate, and methylcellulose revealed that sodium hyaluronate and methylcellulose are pseudoplastic fluids in contrast to chondroitin sulfate, which is a Newtonian fluid. Pseudoplastic fluids are ideal for maintaining the anterior chamber, since they are more viscous at rest. Intermediate viscosity preparations of these three agents used as a thin endothelial coating gave excellent protection from intraocular lens abrasion. A highly viscous agent, eg, sodium hyaluronate 1%, in a thin layer produced extensive endothelial cell damage because it transmitted excessive shear force to the endothelium. A highly viscous agent, sodium hyaluronate 1% in a thick layer produced a physical barrier to compression with little endothelial damage. A low-viscosity agent, balanced salt solution provided insufficient protection against intraocular lens abrasion.

Topics: Animals; Cattle; Chemical Phenomena; Chemistry; Chondroitin; Chondroitin Sulfates; Cornea; Eye Injuries; Hyaluronic Acid; Hydrogen-Ion Concentration; Lenses, Intraocular; Methylcellulose; Viscosity