Corneal Transplantation

Aims: Thiamethoxam (THIA) is a pesticide that has been widely used for its effectiveness in controlling and preventing insect pests. However, the use of THIA diffused in soil, surface and groundwater pose severe toxicity to the ecosystem. The hazardous pollution caused by the toxicity of THIA demands for remediation to ensure degradation of THIA into its safe constituent elements. Thus, the aim of this study is to isolate and identify potential THIA degraders for future bioremediation. Methodology and results: Bacteria were isolated from soil sample collected at a corn plantation which utilizes THIA as a source of pesticide. Overall, two bacterial isolates were isolated from the soil sample. The bacterial isolates were screened and identified for their ability to degrade pesticide by culturing in minimal salt media (MSM) supplemented with 50 mg/L THIA. The growth of isolates was observed and analyzed through spectrophotometry analysis, standard plate count method and pH value of culture medium. As a result, isolate THIA 1 had been found to possess the ability to degrade pesticide as it showed a high rate in growth of bacteria compared to its controls. Meanwhile, isolate THIA 2 showed no degrading activities while under treatment as it showed similar rate of growth towards its control. Isolate THIA 1 was identified as Acinetobacter sp. UMTFA THIA 1. Conclusion, significance and impact of study The isolation and identification of the pesticide degrading bacteria will provide promising source of pesticide degrading enzyme that can be further developed for enzymatic pesticide biodegradation. This will pave the way forward in bioremediation where new effective degradation tools can be developed for pesticide residue which otherwise lead to serious ecological problem.
Thiamethoxam ; Bacteria ; Corneal Transplantation

Corneal ulcerations are divided into two morphologic types: central and marginal. Marginal corneal ulcerations are characterized by focal, muItifocal, multifocal or diffuse ulcerative, infiltrative, or vascular involvement of the peripheral cornea, and the exact pathogenesis of these ulcerations is not clearly understood but infectious, toxic or autoimmune factors may be involved. The authors treated one peripheral corneal ulcer patient, no respond to steroid and antibiotic therapy, with lamellar keratoplasty and had a good result.
Cornea ; Corneal Transplantation* ; Corneal Ulcer* ; Humans ; Ulcer

Corneoscleras were stored in 4 degrees C, 98% glycerin and were examined histologically at various storage periods. There were no remarkable pathologic changes in the stainability or arrangement of collagen fibers in stored corneoscleras from one month to 33 months. 12 eyes of 12 patients underwent tectonic or therapeutic keratoplasty with them. The integrity of the globe was maintained in all cases and vision improved in three cases without the second operation. One case achieved visual improvement by optical keratoplasty. In four cases, the vision may be improved by the second operation, such as optical keratoplasty and keratoprosthesis.
Collagen ; Corneal Transplantation ; Glycerol ; Humans

From the year 1985 – 1997, 250 cases of corneal transplatation were reviewed. The diameter of grafted cornea varied from 8-15mm, among them 113 cases of graft larger than 10mm. After the operation, visual acuty was improved in almost patients. In the case of internal therapy is impossible, this surgery is the only approach to save the eyeball, moreover, the optical function was restored significantly. In the case of progressive infection, which is not responded to the therapy, threatening the eyeball corneal transplantation must be indicated early.
Corneal Transplantation ; Case Reports ; Epidemiology

Objective: We reported a case of Descemet's membrane detachment (DMD) following ripcord removal of a Baerveldt shunt in a post-corneal transplant eye, and the interventions done. Method: This is a case report Results: A 65-year-old male with multiple surgeries (phacoemulsification, two corneal transplants, and Baerveldt shunt implantation) in the right eye developed increased intraocular pressures, prompting removal of the intraluminal stent (ripcord) of the shunt. This was complicated by hypotony and DMD. Ripcord reinsertion and viscoelastic injection were performed to reattach the Descemet's membrane (DM) but failed. 0.1mL of 14% perfluoropropane (C3F8) gas was injected into the anterior chamber that successfully reattached the DM with return to pre-operative best-corrected visual acuity after 1 week. Conclusion Injection of an expansive gas (C3F8) was effective in repairing a corneal graft DMD in an eye with a Baerveldt shunt.
Glaucoma Drainage Implants ; Corneal Transplantation

PURPOSE: To evaluate the corneal thickness values before and after refractive keratoplasty with the Topcon SP-2000 noncontact specular microscope(Topcon American Corp.) and the common standard ultrasonic pachymeter. METHODS: Corneal thickness was measured in 40 eyes of 20 patients, 5 times each before and after keratoplasty, with the Topcon SP-2000P and an ultrasonic pachymeter (DGH 1000, DGH Technology Inc.). The main outcome measures were accuracy and reproducibility as assessed with coefficient of variation (CV) of corneal thickness measurements. RESULTS: The reproducibility of corneal thickness measurements was better with the ultrasonic pachymeter (CV 0.36%) than with the Topcon SP-2000 (CV 1.23%). Mean corneal thickness measured by the Topcon SP-2000P before and after keratoplasty was significantly less than the mean values obtained with the ultrasonic pachymeter (14.4 micro meter; P<.0001, 5.6 micro meter; P<.01; respectively). Compared with theoretical ablated corneal thickness, ablated corneal thickness measured with the Topcon SP-2000P was significantly less (P<.01) than values obtained with the ultrasonic pachymeter (P=0.07) CONCLUSIONS: The noncontact Topcon specular microscope provides measurements of corneal thickness that are significantly less than those of the ultrasonic pachymeter, both before and after keratoplasty. These results indicate that these 2 techniques are not clinically comparable, thereby precluding interchangeable use of their data in planning or assessing keratoplasty.
Corneal Pachymetry* ; Corneal Transplantation ; Humans ; Outcome Assessment (Health Care) ; Ultrasonics*

PURPOSE: To evaluate clinical effects of laser thermal keratoplasty (LTK), LTK was performed in patients with presbyopia or hyperopia. METHODS: LTK was performed in 38 patients who was older than 45 between May and December 2001. Preoperative contact lens fitting and wearing for patients to experience the monovision was tried in all patients for one week. With LTK, we intended patients used dominant eyes for distance vision and nondominant eyes for near vision. Patients' satisfaction, refractive change and near visual acuity were evaluated for least 3 months after surgery. RESULTS: The mean improvement of near vision was 5.16 lines by test with Korean near vision chart. 79% (30 of 38) of patients were satisfied with the results of LTK. CONCLUSIONS: Monovision with LTK is thought to be a good option in patients with presbyopia.
Corneal Transplantation* ; Humans ; Hyperopia ; Presbyopia ; Visual Acuity

Oxygen consumption of the rabbit cornea was determined by Warburg direct method in exposed and compared with covered. Six, twelve, twenty-four, forty-eight and seventy-two hours after death, respectively, 8 corneas (4 corneas were exposed and other 4 corneas were covered) from each series were used for QO2 measurment and compared with fresh corneas. The results were as follows; 1) Oxygen consumption of fresh corneas were found to be about 0.79 micro IO2/mg (dry wt.)/hr and there was no significant difference between both eyes. 2) Until twelve hours after death, oxygen consumption in covered group was greater than in exposed group. 3) Twenty-four hours after death, exposed group consumed more oxygen than covered group and QO2 volume tended to increase in the course of time, probably by bacterial growth, but statistically not significant. 4) As the results described above, it was presumed that the cornea should be preserved for keratoplasty at least within twelve hours after death of the host and covered group would be better than exposed group.
Cornea* ; Corneal Transplantation ; Oxygen Consumption* ; Oxygen*

Lamellar keratoplasty was done to six eyes with preserved rabbit corneas including scleral rim of 1-2mm which were preserved in three kinds of 5cc. alcohol-glycerine (A.G) solution at room temperature for the period of one month to three years and their macroscopical and histological study was carried out. Three kinds of solution were; 1. A.G. No.1 solution; 50% ethyl alcohol and 100% glycerine mixed by equal ratio. 2. A.G. No.2 solution; 50% ethyl alcohol and 100 % glycerine mixed by two to one ratio. 3. A.G. No.3 solution; 50% ethyl alcohol and 100% glycerine mixed by three to one ratio. The results of the above mentioned lamellar keratoplasty with the corneas preserved in three solutions were uniformly good in all groups. The results of keratoplasty with the corenas preserved for 3 years were as follows; 1. Transplantation of the preserved corneas in A. G. No.1 solution showed transparent adhesions in two eyes, partial opacity in one, total opacity in two, and rejection in one. Neo-vascularization in this groupwas more prominent than in other groups. 2. Transplantation of the corneas preserved in A.G. No.2 solution resulted in transparent adhesion in four eyes, partial pacity one, and total opacity in one and this result could be evaluated as the best of all three groups. 3. Transplantation of the corneas preserved in A.G. No. 3 solution showed transparent adhesion in two eyes, partial opacity in three, and total opacity in one and this result was slightly inferior to that of the second group. 4. Lamellar keratoplasty with human cornea preserved in A.G. No.2 solution for 18 and 33 months in the 2 cases of corneal leucoma after recurrent meta-herpetic keratitis, resulted in success respectively.
Cornea* ; Corneal Transplantation* ; Ethanol ; Glycerol ; Humans ; Keratitis