Corneal neovascularization is a major complication of several corneal diseases and many investigations have been performed to inhibit the ingrowth of vessels in the corneal tissue. In this experiment, the author investigate the clinical effect of cartilage to corned neovascularization. Using 12 albino rabbits, corneal neovascularization was induced by alkali burns, and cartilage was implanted subconjunctivally at the limbus before or after the alkali burns. Except 2 eyes which showed inhibition of neovascularization after implantation of cartilage, there was no demonstrable difference between control and cartilage-implanted eyes.
Alkalies ; Burns ; Cartilage* ; Corneal Diseases ; Corneal Neovascularization* ; Rabbits ; Zea mays

The effect of topical perfluorophenanthrene on corneal neovascularization was studied at chemically induced corneal burn on the rats. A central corneal burn was produced with 10% NaOH. Right eye was treated with perfluorophenanthrene and gentamicin eye drops four times a day for five days, the left with balanced salt solution and gentamicin eye drops as control. After five days treatment the rats were sacrified, and the tissue slide were prepared for microscopIc examination. Using slide projector the tissue slide were projected and magnified on the screen. The number of corneal new vessels, the distance of new vessel from the limbus, and the degree of increased corneal thickness were calculated in both groups. As the result there were no statistical difference between two groups. Analysis using ANOVA program showed the fact that statistically significant correlationship between the degree of corneal thickness and the number of the new vessels and the distance from the limbus were found. The result could confirm the mechanism of corneal neovascularization that disarrangement of the compact corneal tissue could allow the formation of the new vessels.
Animals ; Burns ; Corneal Edema ; Corneal Neovascularization* ; Gentamicins ; Ophthalmic Solutions ; Rats*

PURPOSE: The purpose of this study was to determine whether immunosuppressant, rapamycin could inhibit corneal angiogenesis induced by angiogenin and to evalutate its role by micropocket assay. METHODS: The rabbit's eye was implanted intrastromally into the superior cornea with pellet for the control group, pellet containing of angiogenin for the angiogenin group, and pellet containing of angiogenin and rapamycin for the angiogenin+rapamycin group. Biomicrographically, corneal angiogenesis was evaluated for 14 days after pellet implantation, based on the number and the length of new vessels. The neovascularized cornea also was examined histologically. RESULTS: We could observe that the angiogenin inducing corneal angiogenesis was inhibited by rapamycin. The score of neovascularization was significantly decreased in the angiogenin+rapamycin group than in the angiogenin group at 3, 7 and 10 days after pellet implantation (p<0.05). Histologically, the cornea of angiogenin+rapamycin group also showed much less new vessels than that of angiogenin group, in which inflammatory cells and edema was observed. CONCLUSIONS: Rapamycin appears to inhibit angiogenin induced angiogenesis in a rabbit corneal micropocket assay and may have therapeutic potential as an antiangiogenic agent.
Cornea ; Corneal Neovascularization* ; Edema ; Rabbits* ; Sirolimus*

PURPOSE: To investigate the efficacy of a subconjunctival injection of alphaVbeta5 integrin antibody on corneal angiogenesis induced by chemical epithelial denudation in a rabbit eye model. METHODS: One week after debridement by heptanol, rabbits were treated with a subconjunctival injection of alphaVbeta5 integrin antibody or control immunoglobulin G weekly for 2 weeks. Rabbits that did not receive injection after debridement served as the untreated group. The percentage of neovascularized corneal area was calculated by biomicroscopy, and the sectioned area and number of new vessels were calculated by histological examinations. RESULTS: At 7 days after the first injection, alphaVbeta5 integrin antibody-treated eyes had 9.5% (P=0.02) and 6.8% (P=0.03) less neovascularized corneal area than vector-treated eyes and untreated eyes, respectively. At 7 days after the second injection, alphaVbeta5 integrin antibody-treated eyes had 21.1% (P=0.02) and 18.3% (P=0.02) less neovascularized corneal area than vector-treated eyes and untreated eyes, respectively. Light microscopic examination showed a smaller neovascularized corneal area and a reduced number of new vessels in the alphaVbeta5 integrin antibody-treated eyes compared to the control eyes. CONCLUSIONS: Subconjunctival injection of alphaVbeta5 integrin antibody effectively reduces experimental corneal neovascularization induced by chemical injury, and could be used as a corneal angiogenesis inhibitor in the future.
Corneal Neovascularization* ; Debridement ; Heptanol ; Immunoglobulin G ; Rabbits

PURPOSE: To determine the efficacy of photodynamic therapy (PDT) with verteporfin (Visudyne(R), Norvatis Ophthalmics AG, Hettingen, Switzerland), a benzoporphyrin derivative, in the treatment of corneal neo-vascularization (CN) in a rabbit eye model. METHODS: CN was induced by placing instrastromal sutures in the cornea. Two weeks after suturing, verteporfin was administrated intravenously and 1 hour later, the right eye (treated group) was exposed to a laser with a 689 nm wavelength, and the left eye was used as the control. The changes in CN were analyzed using biomicroscopy and optical microscopy in twelve rabbits. RESULTS: The mean percentages of the neovascular area in the control and treated groups were 96.4 +/- 1.9% and 90.3 +/- 3.5% (P=0.009) at three days after the PDT, 88.6 +/- 4.6% and 71.6 +/- 6.2% (P<0.001) at one week, and 76.8 +/- 4.4% and 43.6 +/- 15.1% (P<0.001) at two weeks, respectively. Optical microscopy showed significant differences between the control and treated group in terms of the area and number of CN (P<0.05). CONCLUSIONS: PDT with verteporfin is a safe and effective procedure for regressing CN. However, a further study will be necessary.
Animals* ; Cornea ; Corneal Neovascularization* ; Microscopy ; Photochemotherapy* ; Rabbits ; Sutures

We investigated mean keratometric vale(K) after penetrating keratoplasty(PKP) and analyzed the factors which affected the postoperative mean K. We obtained mean K at postoperative 3 months in the 65 eyes of 65 patients which PKP of PKP combined with intraocular lens(IOL) implantation was done, and analyzed those values according to sex, age, preoperative diagnosis, preoperative corneal neovascularization, methods of trephination, methods of suture and methods of operation. The postoperative mean K of all patients was 42.83 diopters(D) and 43.32D in the recipient cornea without neovascularizaion, 42.51D with neovascularization, 42.72D in the cases of hand-held trephination and 43.27D in Hessvurg-Varron trephination, which had no statistical significant difference between K and sex, age, preoperative diagnosis, methods of suture, and methods of operation. This results will be helpful to predict the change of K ofter PKP, and give a better refractive results to use the operator's own mean K for the IOL calculation in the case of PKP comvined with IOL implantation.
Cornea ; Corneal Neovascularization ; Diagnosis ; Humans ; Keratoplasty, Penetrating* ; Sutures ; Trephining

PURPOSE: This study investigated the importance of alphavbeta5 function during vascular endothelial growth factor (VEGF) induced corneal angiogenesis by examining the effects of antibody to alphavbeta5 that blocks alphav 5-mediated cell adhesion to vitronectin. METHODS: A hydrogel disk containing 500 ng of VEGF was implanted into the superior corneal stroma of each of sixteen New Zealand white rabbit eyes. Each eye also received a second hydrogel disk placed adjacent to the first, randomized to contain either 40 g of antibody to alphavbeta5 (n=8) or phosphate-buffered saline (PBS)(n=8). Both disks were positioned 1.2 mm apart from the superior limbus. Eyes were examined daily under a stereomicroscope by two observers and assigned an angiogenesis score based on number and length of new blood vessels. RESULTS: On days 3 through 7 postimplantation, angiogenesis scores were significantly lower in eyes treated with antibody to alphavbeta5 (averaged score=16.33) as compared to eyes treated with PBS (averaged score=26.52)(P<0.05, Wilcoxon signed rank test). CONCLUSIONS: In a rabbit corneal micropocket assay, antibody to alphavbeta5 inhibits corneal angiogenesis induced by VEGF. Substances that target the integrin alphavbeta5 subunit may have therapeutic potential in disorders characterized by ocular neovascularization.
Blood Vessels ; Cell Adhesion ; Corneal Neovascularization* ; Corneal Stroma ; Hydrogel ; New Zealand ; Vascular Endothelial Growth Factor A ; Vitronectin

Limbal epithelium plays a great role in reconstruction of damaged corneal epithelium and early limbal transplantation showed better results in limbal injury.However, there is no consensus about the appropriate time for limbal transplantation.We, therefore, investigated the results of autologous limbal transplantation (ALT)immediately following limbal epithelial injury in rabbits.We classified the rabbits in three groups whether the application of ALT and therapeutic contact lens were done or not.Injury of limbal and corneal epithelium was made by application of n-heptanol and tarsorrhaphy was done in all groups.ALT from the healthy fellow eye was done in Group 1 and Group 2 but not in Group 3, control group.Therapeutic soft contact lens was applied to Group 2 after ALT.We evaluated epithelial defect, haze, and neovascularization of corneas at 3 days, 1 week, and 2 weeks after operation.We also examined tissue specimen of corneas after two weeks of operation.Epithelial defect was almost healed within 2 weeks after operation in Group 1 and Group 2, but Group 3 showed persistent epithelial defect. Corneal neovascularization and haze were the most severe in Group 3, but was not so severe in Group 1 and Group 2, and there was no significant difference between the two groups.On histopathologic examination, Group 1 and Group 2 showed almost normal corneal epithelium though a few inflammatory cells and goblet cells were observed in some cases but control group showed severe inflammaton and many new vessels and goblet cells.In conclusion, ALT immediately following severe limbal injury is effective in reconstructing corneal epithelium.
Consensus ; Contact Lenses, Hydrophilic ; Cornea ; Corneal Neovascularization ; Epithelium ; Epithelium, Corneal ; Goblet Cells ; Heptanol ; Rabbits*

PURPOSE: To evaluate the clinical effect of photodynamic therapy (PDT) with verteporfin (Visudyne(R), Novartis Ophthalmics AG, Hettingen, Switzerland) in the treatment of corneal neovascularization. METHODS: We performed photodynamic therapy on one eye with corneal neovascularization associated with lipid keratopathy, and on another eye with corneal neovascularization after corneal perforation. Verteporfin was administrated intravenously for 10 minutes at a dose of 6 mg/m2 of body surface area. Fifteen minutes after the start of administration, a 689 nm nonthermal laser light (Opal photoactivator, Coherent Inc., USA) was delivered directly over the neovascular network for 83 seconds with a spot size of 4000 micrometer. The patients were followed up at 3 days, 1 week, 1 month, and 6 months after treatment. RESULTS: In both cases, new vessels were successfully occluded after the photodynamic therapy. No recanalization of new vessels was observed at last follow-up and no complications were observed. CONCLUSIONS: PDT with verteporfin is considered to be a safe and effective procedure to regress corneal neovascularization.
Body Surface Area ; Corneal Neovascularization* ; Corneal Perforation ; Follow-Up Studies ; Humans ; Photochemotherapy*

The authors studied the effect of locally administered interferon alpha on ocular neovascularization. Ten albino rabbits were divided into two groups and the effect of interferon subconjunctival injection on new blood vessel growth(group I) and regression of established neovasculization(group II) was observed in rabbit cornea. A 7-0 mersilk suture was placed into the corneal stroma 3 mm from the superior limbus of each eye in 5 rabbits in group I. Interferon alpha 2a(1.5 million units/day) was injected subconjunctivally in one eye for 7 days(group I a), the contralateral eye received 0.5 ml of normal saline(group I b). New vessel growth was measured using a grading system(grade 0 to 4) by a masked observer. In group II, 15 days after the placement of corneal suture for the development of complete corneal neovascularization, interferon alpha 2a(1.5 million units/day, group II a) and normal saline(group II b) was injected for 9 days in each eye in 5 rabbits to observe regression of the new vessels. Interferon injection eyes showed slower corneal new vessel growth than the control eyes in group I at 5 and 10 days after placement of the suture(p<0.05), but the authors did not observe regression of the new vessels after 9-days injection of interferon in group II.
Blood Vessels* ; Cornea* ; Corneal Neovascularization ; Corneal Stroma ; Interferon-alpha* ; Interferons* ; Masks ; Rabbits ; Sutures