The Prognostic Factors that Influence in Near Vision after Accommodative Intraocular Lens Implantation

PURPOSE: To evaluate the prognostic factors to determine the uncorrected near visual acuity of patients who undergone routine cataract surgery and WIOL-CF(R) (Gelmed international, Kamenne Zehrovice, Czech Republic) accommodative intraocular lens implantation. METHODS: This study evaluated 46 eyes of 27 patients who had undergone routine cataract surgery and WIOL-CF(R) accommodative IOL implantation. We checked visual acuities at near and distant before surgery. And we also checked age and gender of patients and manifest refraction, corneal astigmatism and axial length of eyes at that time. We analyzed association between these factors and uncorrected near visual acuity at postoperative 6 and 12 month. RESULTS: Univariate linear regression analyses between uncorrected near visual acuity and preoperative patients characteristics suggested that the age of patients was the only statistically significant independent variable on uncorrected near visual acuity at postoperative 6 (p < 0.001) and 12 (p < 0.001) month. Multiple regression analyses also revealed the same results (p = 0.021 at postoperative 6 month and p = 0.042 at postoperative 12 month). CONCLUSIONS: This study suggest that the age is the one of the most important prognostic factors of postoperative uncorrected near visual acuity after WIOL-CF(R) accommodative intraocular lens implantation.

Beta ig-h3 promotes renal proximal tubular epithelial cell adhesion, migration and proliferation through the interaction with alpha3beta1 integrin

Betaig-h3 (betaig-h3) is a secretory protein composed of fasciclin I-like repeats containing sequences that allows binding of integrins and glycosaminoglycans in vivo. Expression of betaig-h3 is responsive to TGF-beta and the protein is found to be associated with extracellular matrix (ECM) molecules, implicating betaig-h3 as an ECM adhesive protein of developmental processes. We previously observed predominant expression of betaig-h3 expression in the basement membrane of proximal tubules of kidney. In this study, the physiological relevance of such localized expression of betaig-h3 was examined in the renal proximal tubular epithelial cells (RPTEC). RPTEC constitutively expressed betaig-h3 and the expression was dramatically induced by exogenous TGF-beta1 treatment. betaig-h3 and its second and fourth FAS1 domain were able to mediate RPTEC adhesion, spreading and migration. Two known alpha3beta1 integrin-interaction motifs including aspartatic acid and isoleucine residues, NKDIL and EPDIM in betaig-h3 were responsible to mediate RPTEC adhesion, spreading, and migration. By using specific antibodies against integrins, we confirmed that alpha3beta1 integrin mediates the adhesion and migration of RPTECs on betaig-h3. In addition, it also enhanced proliferation of RPTECs through NKDIL and EPDIM. These results indicate that betaig-h3 mediates adhesion, spreading, migration and proliferation of RPTECs through the interaction with alpha3beta1 integrin and is intimately involved in the maintenance and the regeneration of renal proximal tubular epithelium.

The Effect of Anterior Chamber Irrigation with OcuLarsol(R) on the Corneal Endothelial Cells

PURPOSE: To verify the stability and effect of OcuLarsol(R), which was newly developed for irrigating solution, by evaluating influence on cornea. METHODS: In vivo study group, after an irrigation and aspiration instrument was put into rabbit's anterior chamber: one eye was irrigated with OcuLarsol(R) for 15 minutes, and the other eye with the balanced salt solution (BSS(R), Alcon, USA). After the operation, corneal changes were observed for a week. In vitro study group, after enucleating of rabbits' eyeballs, corneas were mounted in a dual chambered specular microscope and perfused with glutathione bicarbonate Ringer's solution (GBR) for one hour: one cornea of the pair was perfused with OcuLarsol(R) and the other cornea was perfused with BSS(R) for 2-3 hours. After perfusion, corneal swelling rates and endothelial permeability were measured. RESULTS: In vivo study group, central corneal thickness measurement and endothelial cell count showed that there was no significant difference between the two groups on the day of operation, and 1st, 3rd and 7th day after the operation (p>0.05). Corneal endothelial observation with Alizarin red S, HandE stain, and scanning electron microscope detected no difference in cell shape and density. In vitro study group, corneal swelling rates and endothelial permeability showed no significant difference between OcuLarsol(R) and BSS(R) group and transmission electron microscope showed endothelial cells with normal organelles in all groups. CONCLUSIONS: There was no significant difference between the two irrigating solutions, BSS(R) and OcuLarsol(R), in terms of effect and side effects.

Corneal Endothelial Morphometric Changes after Laser in Situ Keratomileusis with Residual Thickness less than 250 micro meter

PURPOSE: To evaluate endothelial cell changes following LASIK with residual corneal thickness of less than 250 micro meter. METHOD: We performed noncontact specular microscopy preoperatively, and 1 week, 1, 3, 6, 9 months after surgery to examine 82 eyes which had undergone LASIK. Corneal endothelial density (CD), coefficient of variation of the cell area (CV), and the percentage of hexagonal cells(hexagonality, 6A) were obtained according to the corneal endothelial cell analysis program. Analysis was done according to the parameters such as residual stromal bed thickness, number of laser pulse and percentage of ablated stromal thickness and preoperative spherical equivalent. RESULTS: Changes in CD and CV showed no significant difference throughout the follow-up period after surgery. Hexagonality, however, decreased after surgery. In particular, corneas with residual thickness of less than 235 micro meter or the number of laser pulse over than 400, or ablation more than 30% of stromal thickness showed significant decrease in hexagonality. CONCLUSIONS: This results suggest that LASIK with deep ablation might cause corneal endothelial damages, and at least 235 micro meter or more of residual thickness should be preserved to avoid endothelial damages.

Endothelial Function of Cornea Preserved in Korean Corneal Storage Media

PURPOSE: To evaluate the endothelial function of cornea preserved in newly developing korean corneal storage media (CS002, CS003) by estimating the permeability of corneal endothelium and the change of corneal thickness. METHODS: The cornea were divided into six experimental groups - fresh group immediately after enucleation, 4degrees Cmoist chamber group preserved for 24 hours and 48 hours, Optisol & CS002 group for 1, 3, 5, and 7 days, and Likorol & CS003 group for 7, 10, and 14 days after enucleation, and then corneal endothelial permeability(Pac) was measured using carboxyfluorescein solution. Corneal thickness was measured using pachymeter(fine focus adjustment) of the specular microscope. RESULTS: Corneal endothelial Pac (x1 0(- 4) cm/min) was 3.64+/-0.33 in fresh group, 4.79+/-0.28 in 4degrees Cmoist chamber group for 24 hours. Each endothelial Pac of CS002 group at 5 and 7 days was 5.81+/-0.55 and 5.65+/-0.58, which were different with 4degrees Cmoist chamber preservation group for 24 hours(p<0.05) but not different with Optisol groups at same days. Each endothelial Pac of CS003 group at 7, 10, and 14 days was 4.34+/-0.34, 4.66+/-0.59, and 4.66+/-0.27, which were not different from those of Likorol. Each corneal thickness of CS002 and Optisol group at 7days was 417.80+/-19.37 mu m and 421.00+/-19.75mu m, which were resemble increment. Corneal thickness was 426.75+/-22.43mu m in CS003 group and 476.00+/- 40.08mu m in Likorol group at 7days. There was statistical difference between the two group(P<0.05), and this difference was sustained for 14days (P<0.05). CONCLUSION: There was no difference in the effect on corneal endothelial permeability between korean corneal storage media such as CS002 and CS003, and that of previous corneal storage media such as Optisol and Likorol. Corneal thickness of cornea preserved in korean corneal storage media was thinner than that of Likorol.

Protective Effect of Hyaluronic Acid on the Corneal Endothelial Function Against Free-Radical Damage

PURPOSE: To investigate the protective effects of hyaluronic acid with glutathione and ascorbic acid on corneal endothelial function against free-radical damage. METHODS: bovine corneal endothelial(BCEN) cells were treated with a flux of chemically generated superoxide anion produced by the combination of 1 mM hypoxanthine and 0.06 U/ml xanthine oxidase(HX-XO) for 10 minutes, and rabbit corneas were mounted in the dual-chamber specular microscope and perfused with bicarbonate Ringer(BR) solution for one hour and their endothelial surface was exposed to HX-XO for five minutes, and then perfused with glutathione, hyaluronic acid, or ascorbic acid in BR solution for three hours. BCEN cells was observed using MTT assay and rabbit corneal thickness was measured every 15 minutes and corneal swelling rates were calculated by linear regression analysis. Also, corneal endothelial permeability was measured using carboxyfluorescein and fluorometer. RESULTS: MTT assay showed less cytotoxicity in the cells treated with glutathione, hyaluronic acid, or ascorbic acid compared to HX-XO alone. Glutathione, hyaluronic acid, or ascorbic acid reduced the rabbit corneal swelling caused by HX-XO. Corneal endothelial permeability(Pac) increased in corneas perfused with HX-XO(7.88 x 10 cm/min) while those with BR had Pac of 4.54 x 10 cm/min. Following treatment with glutathione, hyaluronic acid, or ascorbic acid, Pac decreased to 4.96, 6.81, and 5.25 respectively(p<0.05). CONCLUSIONS: In conclusion, these data suggest that hyaluronic acid scavenges HX-XO-generated oxyradicals as well as glutathione and less likely ascorbic acid.

The Change of Corneal Endothelial Permeability and Corneal Thickness after Topical Steroid Treatment

Changes of corneal endothelial permeability and corneal thickness after instillation of topical steroid was evaluated. In five rabbits, 0.1%dexamethasone eye solution was dropped into right eyes, and in another five rabbits, 1%prednisolone acetate eye solution was dropped into right eyes, and each left eyes were used as a control with dropping of Tears Naturale(r)II (Alcon-couvreur, Belgium). After dropping eyedrops for seven days, corneal endothelial permeability and corneal thickness were measured. Mean corneal thickness changed from 371.4 micrometer to 334.2 micrometer after dropping eyedrops in 0.1%dexamethasone group, and from 375.8 micrometer to 347.8 micrometer in control group where no statistical difference was noted between the two groups. Corneal endothelial permeability was 3.58x10(-4)cm/min in 0.1%dexamethasone group, and 3.54x10(-4) cm/min in control group(p>0.05). Mean corneal thickness changed from 347.4 micrometer to 323.8 micrometer after dropping eyedrops in 1% prednisolone acetate group, and from 342.4 micrometer to 335.6 micrometer in control group. There was also no statistical difference between the two groups. Corneal endothelial permeability was 4.08x10(-4)cm/min in 1%prednisolone acetate group, and 4.26x10(-4) cm/min in control group(p>0.05). In conclusion, topical application of 0.1%dexamethasone or 1%prednisolone acetate for a short period may have no effect on corneal endothelial permeability and thickness.

The Effect of Taurine on Corneal Endothelial Damage by Free-radicals

PURPOSE: To investigate the protective effect of taurine on the corneal endothelial damage by oxidative stress. METHODS: Rabbit corneas were mounted in the dual-chambered specular microscope and perfused with bicarbonate-Ringer solution(BR) for 1 hour, and endothelial surface was treated with hypoxanthine-xanthine oxidase(HX-XO) for 5 minutes, and perfused with BR for 3 hours in control group, while perfused with 0.5, 1.0, 2.0 mM taurine in BR in test group. Corneal thickness was measured every 15 minutes and corneal swelling rates were calculated by linear regression analysis. Also, corneal permeability was measured using carboxyfluorescein and fluorometer. Using bovine corneal endothelial cells, MTT assay was done. RESULTS: On MTT assay, cytotoxicity of HX-XO group was 47.69% while those treated with 0.5, 1.0, 2.0 mM taurine were 36.22%, 29.73%, 24.90%, respectively(P<0.05). 0.5, 1.0 and 2.0 mM taurine group (12.88, 10.75 and 8.95 um/hr, respectively) reduced the HX-XO-induced corneal swelling rate(20.08 um/hr)(P<0.05). Corneal endothelial permeability(Pac) showed 7.96 x 10(-4) cm/min in corneas perfused with HX-HO. Also, each taurine solutions markedly reduced Pac(7.00+/-0.29 x 10(-4), 6.51+/-0.25 x 10(-4) and 5.37+/-1.41 x 10(-4) cm/min, respectively)(P<0.05). CONCLUSIONS: The results of this study showed that taurine may prevent hydrogen peroxide-induced corneal endothelial damage.

The Examination of PUVA-Induced Dermatologic and Ophthalmologic Manifestations in Systemic PUVA Therapy / 대한피부과학회지

BACKGROUND: Systemic PUVA therapy is a widely used method for treatment of vitiligo and psoriasis. However, there have been few studies concerning complications of systemic PUVA therapy. OBJECTIVE: We examined the dermatologic and ophthalmologic manifestations in patients receiving PUVA therapy. METHOD: We studied 42 patients who received systemic PUVA therapy for more than six months in our department. RESULTS: The results are summarized as follows. 1. Among the 42 patients, the number of male and female patients were 18(42.9%) and 24(57.1%) respectively. The mean age at the start of PUVA was 42 years and mean cumulative UVA dase was 996 J/cm2. 2. Among the 42 patients, hyperpigmentation found in 9(21.4%), PUVA lentigo in 8(19.0%), pruritus in 5(11.9%) and burn in 3(7.1%). 3. The ophthalmologic manifestations were conjunctivitis(13 cases, 31.0%), pteygium(7 cases, 16.7%), pingueculum(6 cases, 14.3%) and cataract(3 cases, 7.1%). CONCLUSION: Long term exposure to PUVA causes chronic clinical side effects of PUVA. Therefore careful follow-up of patients who receive long term PUVA therapy is necessary.

Epidemiology of Infectious Keratitis(II): A Multi-center Study

To identify risk factors and causative organisms, and to evaluate clinical manifestations, methods and results of treatment in infectious keratitis, an epidemiological study was performed prospectively under the identical protocol from April 1995 to March 2000.Logistic regression analysis was used to evaluate possible risk factors. The 1474 cases of infectious keratitis reported from 22 hospitals were studied. Five hundred forty-four organisms(442 bacteria, 82 fungi, 20 A c a n t h a m o e b a)were detected in 1320 eyes with infectious keratitis excluding 154 herpetic keratitis. The Pseudomonas aeruginosa was the most common organism in bacterial keratitis, and Fusariumspp. was the major isolate in fungal keratitis. Contact lens wear and occupation(industry, forester, miner, fisherman)were the risk factors for bacterial keratitis. Risk factors in fungal keratitis were fifth decade of age, farmer, and systemic diseases(diabetes mellitus etc.). Risk factors in herpetic keratitis were male and occupation(office worker, service, student, housewife). Risk factors in Acanthamoeba keratitis was contact lens wear.

Effect of Ascorbic Acid on Corneal Endothelial Function

It has been reported that ascorbic acid[AA]appears to be actively taken up by the corneal endothelium and protect the endothelium against harmful effects of the oxidative reactions. To investigate the effect of ascorbic acidon the corneal endothelial function, rabbit`s corneas were mounted in the in vitro specular microscope. Corneal endothelium was perfused with ascorbic acid, then switched to AA plus ouabain solution, and vice versa. Also, phloretin was perfused onto the endothelium with AA and ouabain. Andcorneal endothelium was perfused with GBR or AA solution followed by perfusion with ouabain. Corneal thickness was measured during the perfusion and the corneal swelling rate calculated. Corneal endothelial permeability was also measured after perfusion of ascorbic acid. Perfusion with AA showed no corneal swelling, but swelling rate was even lower than GBR control. Corneal endothelial permeability did not change upon AA perfusion. In corneas preperfused with ouabain, AA added to ouabain solution decreased corneal swelling rates induced by ouabain solution[19.9 vs. 40.5 micrometer/hr]. The corneas preperfused with AA also showed decreased swelling rates with subsequent perfusion of ouabain added to AA solution[21.7 vs.28.6 micrometer/ hr]. Phloretin inhibited the effect of AA.However, when ouabain was removed, the corneal swelling plateaued but did not return to baseline thickness in both AA and GBR perfusion.The results of this study showed that AA can increase corneal endothelial pump function and reduce corneal swelling caused by ouabain.

The Effect of Mitomycin-C on the Function of Corneal Endothelial Cells in Rabbit

The purpose of this study is to investigate the toxicity of mitomycin-C[MMC]to the corneal endothelial cells, which is medical adjunct to pterygium and glaucoma surgery.Rabbit corneas were mounted in the in-vitro dual-chambered specular microscope.Corneal endothelium was perfused with the glutathione-bicarbonate-Ringer[GBR]solution for one hour, then, perfused with 0.02%, 0.01%, and 0.005%MMC in GBR solution in experimental groups, and with GBR solution only in control group.Corneal thickness was measured every 15 minutes during perfusion and corneal swelling rate was calculated.Corneal endothelial permeability was also measured in another experiment.In MMC-mixed group, the early swelling rate decreased due to osmolarity of MMC, but after removal of MMC, the swelling rate increased compared to that of the control group.The pattern of increase was not a linear form, but a secondary curve with the plateau. In 0.02%and 0.01%MMC group, corneas swelled significantly, but not in 0.005%group.Corneal endothelial permeability was 4.21 +/-0.50 x10-4cm/min at 0.005%MMC, 4.10 +/-0.93 x10-4cm/min in control, and 4.25 +/-0.48 x10-4cm/min at 0.01% MMC, 3.73 +/-0.73 x10-4cm/min in control. No significant changes in permeability was observed.In conclusion, MMC of 0.01% or higher exposed to corneal endothelial cells induced corneal swelling of which mechanism was thought to be due to inhibition of Na/K-ATPase by MMC.

The Changes of Ultrastructure and Function of the Corneal Endothelial Cell Caused by the New Irrigating Solution(HR solution)

The purpose of this study was to evaluate alterations in corneal endothelial cell function and ultrastructure followed by perfusion with HR solution which is a newly developed irrigating solution in Korea. After paired rabbit corneas were mounted in the in-vitro dual-chambered specular microscope and perfused with glutathione-bicarbonate-Ringer solution(GBR)for one hour, one cornea of the pair was perfused with HR and the other cornea was perfused with BSS(r), BSS Plus(r)or IOCARE(r)solution. Corneal thickness was measured every 15 minutes throughout the perfusion period. Swelling rates were calculated by linear regression analysis. At the end of perfusion, the corneas were fixed in 2.5%glutaraldehyde solution for transmission electron microscopy(TEM)or fixed in mixed solution of 0.5% glutaraldehyde and 0.5% paraformaldehyde for scanning electron microscopy(SEM). In another experiment, corneal endothelial permeability was measured. Swelling rates of rabbit corneas perfused with HR or BSS(r)were 5.57+/-0.97 micrometer/hr and 6.45+/0.74 micrometer/hr respectively(p>0.05), and swelling rates when perfusing with HR or IOCARE(r)were 7.87+/-0.45 micrometer/hr and 7.25+/-0.32 micrometer/hr respectively(p>0.05). Swelling rate of rabbit corneas perfused with BSS Plus(r) was 3.88+/-1.34 micrometer/hr that is lower than that of HR(5.35+/-0.69 micrometer/hr), but the difference is not significant statistically(p>0.05). The endothelial permeability of the cornea perfused with BSS(r) or HR were 2.97+/-0.23x10(-4)cm/min and 3.01+/-0.1 5x10(-4)cm/min respectively which showed no significant differences between the two(p>0.1). TEM and SEM of corneas perfused with HR showed endothelial cells with normal organelles, like with BSS(r) and BSS Plus(r). The results of this study indicate that HR solution maintain the function of corneal endothelium.

Morphologic Evaluation of Cat Corneal Endothelium Preserved in Korean Corneal Storage Medium

No Abstract Available.

The Effect of Antibiotics in the Irrigation Solution on Corneal Endothelial Function

The practice of adding antibiotics to anterior chamber-irrigating solutions as a prophylaxis for endophthalmitis has been used recently.To evaluate corneal endothelial toxicity of different concentrations of antibiotics in irrigating solutions, rabbit corneas were mounted in the in-vitro dual-cham-bered specular microscope and the endothelium was perfused with glu-tathione-bicarbonate Ringer solution (GBR)containing antibiotics such as ofloxacin, vancomycin or cephapirin.Mate corneas were perfused with GBR alone and used as control.Corneal thickness was measured every 15 minutes throughout the perfusion period and corneal swelling rates were calculated. Swelling rates of corneas perfused with 2 /ml or 5 /ml ofloxacin, 60 microgram/ml or1 0 /ml vancomycin, and 10 /ml or 20 /ml cephapirin was not significantly different from that of control (p>0.05).The corneas perfused with 20 /ml cephapirin deswelled probably due to high osmolarity of it.Perfusion with 10 /ml vancomycin plus 5 /ml ofloxacin did not show corneal swelling compared to control (p>0.05).This study demonstrates that the above concentra-tions of antibiotics in irrigating solutions do not affect endothelial function of the rabbit cornea.

T reatment of Myopic Astigmatism using Erodible Mask: One Year Fo l l ow-up Results

After Photorefractive keratecto my[PRK]and Laser in situ keratomileusis[LASIK]for myopic astigmatism correction, we evaluated the change of myopic and astigmatic refraction and analyzed the results. Toric PRK[20 eyes]and Toric LASIK [45 eyes], total 65 eyes were performed using Toric PRK program of Summit Apex Plus and erodible mask and followed up for one year. We analyzed the change of uncorrected visual acuity, best corrected visual acuity, myopic refraction and astigmatic refraction.Mean spherical refraction had decreased from preoperative -4.36 +/-1.19D [PRK]&-8 .83 +/-2.20D[LASIK]to postoperative 12 month -0.25 +/-0.52D[PRK]&-0.21 +/-0.87D[LASIK].Cylindrical refraction had changed from preoperative -1.62 +/-1.09D[PRK]&-2.07 +/- 0.96D[LASIK]to postoperative 12 month -0.16 +/-0 .3 9 D [PRK]& 0.29 +/-0.69D[LASIK].Twelve months after Toric PRK, 64.0% of mean spherical equivalent was included within +/-0.5D and 92.0%was included within +/-1.0D.Twelve months after Toric LASIK, 57.5%of mean spherical equivalent was included within +/-0.5D and 77.5%was included within +/-1.0D.Uncorrected visual acuity was 0.7 or better in 100%of the Toric PRK group and 80.0%of the Toric LASIK group.No eyes in Toric PRK group lost two or more Snellen lines of best corrected visual acuity at postoperative 12 month, while 2 eyes[5.0%]in Toric LASIK group did. We concluded that myopic astigmatism correction using erodible mask was satisfactory.

The Effect of Reablation on the Undercorrected Eye after LASIK

We evaluated the effect of the reablation on the undercorrected eye after the Laser in-situ keratomileusis [LASIK]. The subjects were 21 eyes of 19 patients, who showed undercorrection after the LASIK. Reablation was done on the stromal bed after lifting the original flap aside. Patients were followed up for 1 to 6 months after the reablation. At the time of first LASIK, the mean spherical equivalent[S/E]was -11.29 +/-2.98D preoperatively, -1.90 +/-1.16D at postopera-tive 3 months, the mean amount of correction was -9.60 +/-1.90D. At the time of reablation, the mean[S/E]was -3.26 +/-1.08D, and the mean amount of correction was -3.31 +/-1.11D. Reablation was done only after the refractive error stabilized and did not change over 3 months. One month after the reablation, the mean[S/E]was +0.15 +/-0.98D and 85.7%of the eyes were within +/-1.0D. Six months after the reablation, the mean[S/E]was -0 .1 0 +/-0.66D and 84.6% were within +/-1.0D. The uncorrected visual acuity of 0.6 or more was achieved in 76.2%of eyes at 1 month, and 84.6%at 6 months. The best spectacle-corrected visual acuity [BSCVA]was lost 2 lines or more in 14.3%at 1 month, but none at 6 months after surgery. The BSCVA did not change or gain 1 line or more in 76.2%at 1 month, and 92.3%at 6 months after surgery. There was no problem when lifting the original corneal flap. In conclusion, reablation using the original flaps without new cuts seems to be a redictable, safe method for retreatment.

The Effect of Fluorescein and Indocyanine Green on Corneal Endothelial Function

Both sodium fluorescein[FL] and indocyanine green[ICG] were used for fundus angiography. Recently, these were also used during cataract surgery for enhancement of capsular visualization in white mature or hypermature cataract. So, ICG and FL may influence corneal endothelial function if left in anterior chamber. To evaluate the effect of intracameral FL or ICG on corneal endothelial function, rabbit corneas were isolated &mounted in the in-vitro specular microscope for endothelial perfusion. Experimental corneas were perfused with different concentrations of FL or ICG. Control corneas were perfused with glutathione-bicarbonate Ringer solution[GBR]. Corneal thickness was measured every 15 minutes during the perfusion and corneal swelling rates were calculated. Corneal endothelial permeability[Pa c] was measured according to the method of Watsky et al. The corneas perfused with FL, 2.5% deswelled probably due to high osmolarity. Swelling rates of corneas perfused with 1% and 0.5% FL did not differ significantly from control[p>0.05]. The corneas perfused with 0.01%, 0.005%, 0.002%, and 0.001% ICG swelled significantly[p0.05]. Pa c in corneas perfused with ICG, 0.005% increased markedly compared to control while corneas perfused with FL, 1% showed decreased permeability. The results of this study showed that FL did not affect endothelial function of rabbit cornea in relatively high concentrations while ICG affected endothelial function even in lower concentrations. With respect to clinical use of intracameral ICG, close attention must be paid.

One-year Result of LASIK using 5.0 mmOptical Zone Ablation

The stability, efficacy, predictability, and safety of LASIK with 5.0 mm zone ablation was assessed and the relation between the amount of correction and the amount of ablation was also evaluated to determine how much we need to ablate the corneal stroma. In this study, we present our data on the 125 cases of myopic correction by LASIK, using ExciMed UV 200LA[Summit Technologies Inc. USA]. The patients were divided into 4 groups with preoperative myopia. About 90% of myopic error at the corneal plane was ablated and uncorrected visual acuity[UCVA], best corrected visual acuity[BCVA], intraocular pressure[IOP], and manifest refraction[MR] were checked 1 week, 1 month, 3 months, 6 months, 9 months, and 1 year after LASIK. Spherical refraction improved from -11.94D preop to -0.53D postop one year. 57.1% of eyes was within+/-0.50D and 85.7% was within+/-1.0D of emmetropia one year after LASIK. UCVA of 0.5 or better was achieved in 74.3% of eyes that is because preoperative BCVA was below 0.5 in many cases. BCVA was improved or unchanged, in 90.0% of the eyes one year after LASIK. In eyes with -20.0D of preoperative spherical value or less, ablation of about 90% of spherical value at the corneal plane made 102.9% of attempted correction 9 months after LASIK and 98.3% of attempted correction 1 year after LASIK. In eyes over -20.0D, 89.8% of attempted correction was achieved 9 months after LASIK. In conclusion, this study suggest that the ablation of 90% of preoperative myopic error at the corneal plane is reasonable for LASIK using 5.0 mmablation zone.

The Changes of Ultrastructure and Function of the Corneal Endothelial Cell Caused by Benzalkonium Chloride

The purpose of this study was to evaluate alterations in corneal endothelial cell function and ultrastructure caused by benzalkonium chloride (BAC). Sixteen albino rabbits (32 eyes)were used for this study. One cornea of each matched pair was assigned to experimental group and the other cornea to control group. The experimental groups were divided into 4 groups, of which corneal endothelium were perfused with 0.01%, 0.001%, 0.0002%, and 0.0001% BAC. After paired rabbit corneas were isolated and mounted in the in vitro dual-chambered specular microscope, experimental corneas of each matched pair were perfused with different concentrations of BAC. Control corneas were perfused with glutathione-bicarbonate-Ringer solution(GBR). Corneal thickness was measured every 15 minutes throughout the perfusion period.Swelling rates were calculated by linear regression analysis, and compared to swelling rate of each paired mate perfused with GBR alone. At the end of perfusion,the corneas were fixed in 2.5%glutaraldehyde solution for transmission electron microscopy(TEM). Swelling rates of rabbit corneas perfused with BAC, 0.0001% did not differ significantly from control corneas (p>0.05). But, 0.0002%, 0.001%, and 0.01% BAC differed significantly from control corneas (p<0.05). BAC, 0.0001% showed normal corneal endothelial findings, but 0.0002% and 0.001% BAC showed reversible endothelial cellular injury. BAC, 0.01% showed irreversible endothelial cellular injury such as loss of nuclear membrane and disruption of cellular organelles. The results of this study indicate that long-term use of topical eye solutions containing BAC might induce corneal endothelial damage, especially in the absence of epithelial barrier such as corneal ulcer.