Use of collagen corneal shields versus soft contact lenses to enhance penetration of topical tobramycin

Abstract

We compared the corneal penetration in rabbits of topical tobramycin in the presence of collagen corneal shields and bandage soft contact lenses. A collagen corneal shield was placed on six albino rabbit eyes, while therapeutic soft contact lenses (61.4% poly-2-hydroxyethyl-methacrylate/38.6% water) were placed on six eyes. Four control eyes received no shield or contact lens. Topical tobramycin was applied to all 16 eyes every five minutes for six doses. Samples of aqueous humor were removed at 15 and 60 minutes following the last dose. Collagen corneal shields allowed a significant (P less than .05) increase in tobramycin penetration into the anterior chamber at 60 minutes compared with hydrophilic soft contact lenses or controls.

Prevention of endophthalmitis by collagen shields presoaked in fourth-generation fluoroquinolones versus by topical prophylaxis

“…Experimental and clinical evidence supports the role of collagen shields as a drug-delivery system, especially when they are presoaked in a pharmacological agent in association with adjunctive topical therapy. 22,23 In the S aureus endophthalmitis rabbit model of Kowalski et al, 16 the authors found that topical antibiotic therapy with Vigamox before intraocular bacterial challenge and after intraocular bacterial challenge can prevent bacterial endophthalmitis. Considering the number of cases of clinically diagnosed endophthalmitis in our study, statistical comparison between each treatment and the control group (chisquare test) showed that all regimens except that in the Vigamox group were effective in decreasing the number of endophthalmitis cases.…”

“…In addition, the eye patch can be left undisturbed after surgery while the collagen shield releases antibiotic and there is evidence that collagen shields have a beneficial effect on the corneal epithelium and in promoting healing. 12,13,22,23 A collagen shield may also provide mechanical support to a clear corneal wound in the early postoperative period. To our knowledge, there is no study in the peer-reviewed literature comparing the penetration of gatifloxacin 0.3% (ie, Zymar) into human aqueous and vitreous via topical and collagen shield routes combined.…”

Collagen-Based Drug Delivery and Artificial Tears

“…The collagen shield has been used as a corneal bandage and as a drug delivery device (1-4). Following an initial report of the potential of collagen for drug delivery by Bloomfield in 1978 (5), collagen shields have been used to deliver antibiotics (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18), antifungals (19,20), steroids (21,22), fibrinolytics (23,24), antivirals (25), and immunosuppressives (26,27). One type of collagen shield (Bio-Cor®, Bausch & Lomb Pharmaceuticals, Tampa, FL) is made of porcine scierai collagen formulated into a spherical film similar to an unhydrated soft contact lens.…”

Determination of aqueous and vitreous concentration of moxifloxacin 0.5% after delivery via a dissolvable corneal collagen shield device

“…[6][7][8] In addition, several previous animal studies have evaluated the delivery and penetration of older generation antibiotics such as tobramycin, gentamicin, and vancomycin using presoaked collagen shields. [9][10][11][12] Unfortunately, these older generation antibiotics lack the spectrum of coverage necessary for prophylaxis against the organisms most commonly responsible for postoperative endophthalmitis. 1 Numerous strategies to try to decrease the incidence of postoperative endophthalmitis have been described.…”