Study on treating fungal keratitis of rabbit eyes using collagen shield delivering fluconazole eye drops made by centrifugal method HAN / 中国基层医药

Objective To evaluate the effect of collagen shield delivering fluconazole eye drops made by centrifugal method on treating fungal keratitis of rabbit eyes.Methods Using centrifugal method to make corneal collagen shield,after soaked with fluconazole eye drops,the collagen shields were used to treat fungal keratitis of rabbit eyes.Results The healing focus time of collagen shield delivering fluconazole eye drops group was average 11 days,the healing focus time of only delivering fluconazole eye drops group was average 18 days.The cure rate and effective rate of 2 groups were 78.94%,63.15% and 92.10%,78.94%,there were significance between 2 groups(P<0.05).Conclusion It was innovation for corneal collagen shield delivering fluconazole eye drops made by centrifugal method to cure fungal keratitis,which had broad development foreground.

Efficacy of Ciprofloxacin-soaked Collagen Shields for Treatment of Experimental Staphylococcus aureus Keratitis in Rabbits

In order to study the efficacy of a 0.2% ciprofloxacin-soaked collagen shield for the treatment of Staphylococcus aureus keratitis, an experimental study was performed on 40 eyes of 20 rabbits. Twenty hours after intrastromal injection with S. aureus, the rabbits were divided into four groups: Group 1(10 eyes) was treated with a 0.2% ciprofloxacin-soaked collagen shield with an additional instillation of 0.2% ciprofloxacin drops every 30 minutes for 4 hours; Group 2 (10 eyes) was treated with a 0.2% ciprofloxacin-soaked collagen shield for 4 hours; Group 3 (10 eyes) was treated with 0.2% ciprofloxacin drops every 30 minutes for 4 hours; Group 4 (10 eyes) received BSS every 30 minutes for 4 hours as a control. Bacterial killing was quantitated by culturing corneal homogenates and calculating the number of viable bacteria (colony-forming units) per cornea. Groups 1, 2, and 3 showed significantly reduced numbers of bacteria compared with the control (p0.05). These results suggested that a 0.2% ciprofloxacin-soaked collagen shield may be an effective and convenient mode of therapy for S. aureus keratitis.

Corneal wound Healing Following Excimer Laser Photorefractive Keratectomy Using Pressure Patch, T-lens and Collagen Shield on Rabbit Cornea

We studied the healing course and histologic change of ablated rabbit cornea following excimer laser photorefractive keratectomy using three different corneal wound healing methods; pressure patch, T-lens, collagen shield. Nine rabbits(18 eyes) were divided into three different groups according to its treatment method. Corneal status including the corneal haze, conjunctival injection, discharge amount at postoperative 1st day, 2nd day and 3rd day were the same, irrespective to the treatment method and corneal wound healing rate show no significant differentces in all the groups. The histologic feature revealed irregular epithelial hyperplasia and keratacyte infiltration in the superficial stromal layer on postoperative 3rd day and 7th day. These reactions lessened at postoperative 1 month. The cornea treated with pressure patch group revealed more severe tissue reaction when compared with the other groups, T-lens and collagen shield. These results suggest that the corneal wounds produced by excimer laser can be managed by T-lens as an another alternative method of wound treatment.

Corneal Epithelial Wound Healing After Excimer Laser Photorefractive Keratectomy

We studied the effects of three different treating methods on corneal repithelization after PRK such as pressure patch, therapeutic contact lens and collagen shield. The degree of pain among three different treating groups showed same results without difference. The postoperative corneal wound healing rate in collagen shield group was slower than the other groups at first day. The corneal wound healing duration in therapeutic contact lens was faster than the other groups. Therefore we could obtained the results that therapeutic contact lens treated group is clinically excellent method for accelerating corneal wound healing after excimer laser photorefractive keratectomy.

The Comparison of the Effect of Therapeutic Lrens, Collagen Shield, and Tarsorrhaphy on Stromal Inflammation after Photorefractive Keratectomy in a Rabbit model

Reducing inflammation after photo refractive keratectomy may decrease postoperative pain and reduce corneal haze intensity. We evaluated the effect of the therapeutic lens(T-lens) and collagen shield on stromal inflammation. Adult New Zealand white rabbits were subjected to excimer laser PRK. Polymorphonuclear leukocytes(PMNs) of ablated corneal stroma were counted 10 hours after surgery with a microscope. The number of PMNs in the central cornea was lower in the T-lens group (29.77 +/- 11.6) and collagen shield group(36.77 +/- 5.9) than in the tarsorrhaphy group (75.33 +/- 14.6). Of all the groups, the eyes which were left unpatched showed the most marked infiltration of PMNs into the wound(226.83 +/- 18.2). The T-lens and collagen shield may reduce postoperative corneal haze intensity better than a pressure patch by suppression of stromal inflammation.

The Effect of a Collagen Shield on Concentrations of Tobramycin in Corneas

Collagen shields made of porcine scleral collagen were immersed in a solution containing tobramycin sulfate(40 mg/ml) for five minutes, then applied to rabbit corneas. One, four and eight hours after application, the corneas were assayed for antibiotics by agar diffusion bioassay. We divided study groups as 4 groups, that is, collagen shield, subconjunctival, therapeutic soft contact lens and topical group, and compared the corneal concentradon of tobramycin in each group. Shields immersed in 40 mg/ml tobramycin produced significantly higher concentrations of tobramycin in the cornea at one and four hours than those of the other groups. Tobramycin concentrations in cornea eight hours after application became lower than those of one and four hours after application but, higher than minimal inhibitory concentration of Pseudomonas aeruginosa. Collagen shield containing antibiotics can serve as a vehicle for drug delivery and may prove superior to current methods for the initial treatment of bacterial keratitis, and preoperative and postoperative antibiotic prophylaxis.