methylcellulose and Foreign-Body-Reaction

In three prospectively randomized groups of patients viscoelastic materials during IOL-implantation have been compared concerning 1. intraocular pressure, 2. endothelial cell count, 3. corneal thickness. Examinations were performed preoperatively, the first, second and fifth postoperative day. There was no statistical difference between hydroxypropylmethylcellulose (2%), hyaluronic acid (1%) and air. Examinations were performed preoperatively the first, the second and the fifth postoperative day. There was no statistically significant difference between all groups of patients, Advantages and disadvantages for routine use of viscoelastic substances are discussed.

Topics: Corneal Stroma; Endothelium, Corneal; Foreign-Body Reaction; Humans; Hyaluronic Acid; Hypromellose Derivatives; Intraocular Pressure; Lenses, Intraocular; Methylcellulose; Postoperative Complications; Prospective Studies

The present study examined the effects of steroids and lubricants on electrical impedance and tissue response following cochlear implantation in animal models. Guinea pigs were implanted following either no treatment, or intrascalar injection with dexamethasone, triamcinolone, sodium hyaluronate or saline. Cats were implanted following either no treatment, or intrascalar injection with dexamethasone, triamcinolone or a mixture of triamcinolone with sodium hyaluronate. In guinea pigs, impedance changes and intracochlear tissue response were less for the hyaluronate and saline groups. In cats, impedance in the dexamethasone group increased similar to non-treated cats. Impedance of triamcinolone treated cats remained low for about two months after implantation, before increasing to levels similar to the other groups. Significant fibrous tissue growth was observed histologically. The results of the present study indicate that a single intracochlear application of hyaluronate or triamcinolone may postpone, but will ultimately not prevent the rise in impedance following cochlear implantation.

Topics: Animals; Cats; Cell Count; Cicatrix; Cochlea; Cochlear Implants; Dexamethasone; Electric Impedance; Electrodes, Implanted; Fibrosis; Foreign-Body Reaction; Glucocorticoids; Guinea Pigs; Hyaluronic Acid; Hypromellose Derivatives; Injections; Lubricants; Methylcellulose; Organ of Corti; Prosthesis Failure; Spiral Ganglion; Tissue Adhesions; Triamcinolone

The preparation and some properties of in situ curing porous acrylic cement, a modification of the traditional bone cement, are described. Through numerous animal experiments, the behavior of the porous cement in a biological environment has been studied. The histological evaluation reveals that hard and soft tissues readily grow into the pores of the cement, thus anchoring the implant to the host tissues. Some inflammatory foci, decreasing in number with residence time, together with varying numbers of multinucleated giant cells were found occasionally in the tissues in and around implants. When implanted in soft tissues, the porous cement behaved favorably with respect to solid acrylic implants because of the immobility of the implants and the absence of ectopic hard tissue formation. The biocompatibility of porous acrylic cement is judged to justify clinical trials in plastic and reconstructive surgery.

Topics: Animals; Bone and Bones; Bone Cements; Carboxymethylcellulose Sodium; Foreign-Body Reaction; Methylcellulose; Methylmethacrylate; Methylmethacrylates; Prostheses and Implants; Wound Healing