MANAGEMENT OF VITREAL LOSS FROM POSTERIOR CAPSULAR RUPTURE DURING CATARACT OPERATION: Posterior Versus Anterior Vitrectomy.

PURPOSE: To compare the efficacy between 23-gauge sutureless pars planar vitrectomy (PPV) and anterior vitrectomy in the management of vitreous loss associated with posterior capsular rupture during cataract surgery. METHODS: Medical records of 139 eyes which sustained posterior capsular rupture and vitreal prolapse to anterior chamber during cataract surgery were retrospectively reviewed. Thirty-two eyes which underwent 23-gauge sutureless PPV (group PPV) and 107 eyes which underwent anterior vitrectomy (group AntV) were compared in postoperative visual and anatomical outcomes, operation time, and complications. RESULTS: No significant differences were found between the groups in final best-corrected visual acuity of 20/40 or better (AntV vs. PPV = 80.4 vs. 90.6%, P = 0.139). However, the visual recovery rates (20/40 or better) 1 day, 1 week, 1 month postoperatively were significantly higher in group PPV (AntV vs PPV = 22.4 vs. 44%, 32.2 vs 58.6, 51.9 vs. 78.1%). Postoperative intraocular pressure-related complications requiring medication were less evident in group PPV (AntV vs. PPV = 52.3 vs. 6.3%, P < 0.001). Twelve cases (11.2%) of group AntV and 0 cases of group PPV underwent secondary operation during follow-up. Although no postoperative complications occurred in group PPV, complications such as endophthalmitis, retinal detachment, cystoid macular edema, intraocular lens instability were observed in the AntV group (none vs. 14%, P = 0.022). CONCLUSION: Twenty-three-gauge sutureless PPV is a safe and reliable solution for managing vitreous loss during cataract surgery. Therefore, it is expected to be considered primarily in institutes with vitreoretinal surgeons.

Long-term outcome and prognostic factor analysis for keratolimbal allografts.

PURPOSE: To evaluate the long-term results of keratolimbal allograft (KLAL) and elucidate the prognostic factors of KLAL survival. METHODS: Twenty-four eyes of 22 patients underwent KLAL one or more times, and were followed up more than 1 year postoperatively. Their medical records were reviewed. The success of KLAL and penetrating keratoplasty (PKP) was evaluated. KLAL success was defined as absence of persistent corneal epithelial defect, corneal conjunctivalization, or neovascularization on the corneal edge of the graft. Prognostic factors for survival of KLAL were analyzed, including preoperative diagnosis, history of graft rejection, symblepharon, concurrent surgery, immunosuppressant dose, and interval for full epithelialization time. The prognostic factors were evaluated by univariate survival analysis or multivariate Cox proportional hazards survival regression. RESULTS: KLAL had been successful in 33.3% of the eyes over an average of 47.9 months. Fifteen episodes of KLAL rejection developed in ten eyes (41.7%), but 13 cases (86.7%) were reversible. Of 45 KLAL procedures, eyelid deformity, symblepharon, and the interval of full epithelialization were significantly associated with KLAL success by univariate analysis, and the presence of symblepharon was identified by multivariate Cox regression analysis as the most important prognostic factor to affect KLAL outcome (p = 0.010). CONCLUSIONS: KLAL has been partly successful for reconstruction of limbal stem cell deficiency, and symblepharon has been identified as a significant prognostic factor for KLAL survival. Surgical correction of symblepharon is important before KLAL and PKP.

Measurement of distance objective visual acuity with the computerized optokinetic nystagmus test in patients with ocular diseases.

BACKGROUNDS: To evaluate the efficacy of a computerized optokinetic nystagmus (OKN) test for determination of objective visual acuity (VA) at distance in patients with various ocular diseases. METHODS: This is a prospective, non-interventional study that included 85 eyes of 71 patients with one or more ocular pathologies. Study patients were classified into group C (39 eyes of 30 patients with central visual damage), group P (24 eyes of 20 patients with peripheral visual defect) and group M (22 eyes of 21 patients with media opacity). Objective distance VA was measured with OKN induction and suppression methods, and the correlation between the objective and subjective VA at distance was evaluated using linear regression analysis. Mean subjective VAs were compared among each objective VA step and among the three groups. RESULTS: Significant correlation was found between subjective distance VA and objective VA determined by both OKN induction and suppression methods in all three groups and in overall patients. In overall patients, the mean subjective VA was significantly different in several objective VA steps (Welch's ANOVA, p < 0.001 for induction and suppression methods). No significant difference in subjective VA among the three groups was found in any objective VA step. CONCLUSIONS: Our objective VA test using OKN induction and suppression methods can be useful in estimating distance VA in patients with various ocular diseases.

Secondary intraocular lens implantation in longstanding unilateral aphakia.

PURPOSE: To investigate the effect of secondary intraocular lens (IOL) implantation on binocular vision in patients with unilateral aphakia uncorrected consecutively for 3 years or more. METHODS: This study included nine patients who underwent secondary IOL implantation, but had remained in a unilateral aphakic state, without being corrected, for at least 3 consecutive years at the time of the secondary IOL implant. They also had a postoperative best-corrected visual acuity of better than 20/40 in both eyes. All patients underwent an ophthalmologic examination including best spectacle-corrected visual acuity and binocular alignment. Stereoacuity was evaluated using the Titmus Stereotest and a stereoacuity of 100 sec of arc or better was designated as "good" stereoacuity. Binocularity was determined using the polarized 4-dot test at distance and at near and the reporting of 4 dots were used to establish fusional ability. RESULTS: Four of the nine patients (44.4%) showed the highest stereoacuity of 40 sec of arc and another four patients (44.4%) showed a stereoacuity of 50 or 60 sec of arc. Only one patient showed "poor" stereoacuity of 200 sec of arc. All the patients could fuse at near and at distance on the polarized 4-dot test. Diplopia and anomalous eye movements were not found in any patient. CONCLUSIONS: Secondary IOL implantation can provide good binocular vision even in patients with unilateral aphakia who had not been corrected for 3 years or more.

Interleukin-17 in various ocular surface inflammatory diseases.

Recently, the association of Th-17 cells or IL-17 with ocular inflammatory diseases such as uveitis, scleritis and dry eye syndrome was discovered. We assessed whether interleukin (IL)-17 was present in the tears of various ocular surface inflammatory diseases and the tear IL-17 concentrations were clinically correlated with various ocular surface inflammatory diseases. We measured concentrations of IL-17 in tears of normal subjects (n = 28) and patients (n = 141) with meibomian gland dysfunction (MGD), dry eye syndrome (DES), Sjögren syndrome (SS), Stevens-Johnson syndrome (SJS), graft-versus-host disease (GVHD), filamentary keratitis, and autoimmune keratitis associated with rheumatoid arthritis or systemic lupus erythematosus. Clinical epitheliopathy scores were based on the surface area of corneal and conjunctival fluorescein staining. The mean concentrations of IL-17 in tears of patients with filamentary keratitis, GVHD, autoimmune keratitis, SS, DES, MGD, SJS were significantly higher in order than that in normal subjects. Tear IL-17 concentration was significantly correlated with clinical epitheilopathy scores in the patients with systemic inflammatory disease, while tear IL-17 was not correlated with clinical severity of the cornea and conjunctiva in the dry eye patients without any systemic inflammatory disease. Tear IL-17 is likely to correlate clinically with corneal disease severity only in the patients with systemic inflammatory disease.

The effect of amantadine on corneal endothelium in subjects with Parkinson's disease.

OBJECTIVE: To evaluate the effect of amantadine on corneal endothelial cells in subjects with Parkinson's disease. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 169 subjects (169 eyes) taking amantadine orally for Parkinson's disease and the same number of age- and gender-matched controls. METHODS: Endothelial indices were compared between the amantadine-treated and age-matched control groups. The amantadine-treated group was divided into 3 subgroups according to the cumulative dose and duration of treatment. Endothelial changes were compared between the amantadine group and the normal control group, and among subgroups. MAIN OUTCOME MEASURES: Slit-lamp biomicroscopy, central corneal thickness (CCT), endothelial cell density (ECD), coefficient of variation, and hexagonality. RESULTS: The amantadine group had significantly lower ECD (mean +/- standard error; 2662.47+/-29.06 vs. 2784.72+/-25.89, P = 0.002), lower hexagonality (56.94+/-1.07 vs. 60.97+/-0.87, P = 0.004), and greater coefficient of variation (35.59+/-0.57 vs. 32.66+/-0.52, P = 0.000) compared with the age-matched control group. Longer duration and higher cumulative dose amantadine therapy led to a greater reduction in ECD (P<0.05) compared with the normal age-matched control group. CONCLUSIONS: Amantadine is more likely to have an effect on corneal endothelial cells in a dose-dependent manner when used long-term.

Complement depletion with cobra venom factor delays acute cell-mediated rejection in pig-to-mouse corneal xenotransplantation.

BACKGROUND: We have demonstrated earlier that porcine corneal xenografts underwent an acute cell-mediated rejection in mice despite the absence of T cells. In the present study, we investigated the effect of complement depletion by cobra venom factor (CVF) on the corneal xenograft rejection in a pig-to-mouse model. METHODS: Porcine corneas were orthotopically transplanted into C57BL/6 (B6) and severe combined immunodeficiency (SCID) mice. For complement depletion, 25 microg of CVF (1 g/kg bodyweight) was injected intraperitoneally on the day before and 1, 3, 5, and 7 days after transplantation. Graft survival was clinically assessed by slit lamp biomicroscopy and the median survival time (MST) was calculated. The grafts were histologically evaluated serially after transplantation using antibodies against CD4, CD8, NK1.1, and F4/80. RESULTS: The CVF treatment significantly prolonged the porcine corneal xenograft survival in both B6 (MST 9.4 vs. 15.5 days; P = 0.0011) and SCID mice (MST 16.4 vs. 20.5 days; P = 0.0474). Histologically, whereas macrophages and CD4(+) T cells were progressively infiltrated into porcine corneal grafts in CVF-untreated B6 mice, the infiltration by both cells was markedly delayed and decreased in the xenografts in CVF-treated B6 mice. Likewise, macrophage infiltration, which was prominent in rejected porcine xenografts in SCID mice, was also reduced in CVF-treated SCID mice. CONCLUSIONS: Our results suggest that complement depletion by CVF delayed, although did not prevent, an acute cell-mediated rejection in a pig-to-mouse corneal xenotransplantation.

In situ intraocular suture techniques for pupilloplasty and suspension of a subluxated intraocular lens.

The modified McCannel and Siepser techniques allow surgeons to create a locking knot at the extraocular space to maintain a closed chamber. The authors demonstrate that this method made the pupilloplasty easy and applied it to suspend a subluxated intraocular lens with scleral fixation of haptics.

Ultrasound energy in phacoemulsification: a comparative analysis of phaco-chop and stop-and-chop techniques according to the degree of nuclear density.

BACKGROUND AND OBJECTIVE: To evaluate the amount of ultrasound energy used, corneal endothelial cell loss, and central corneal thickness using the phaco-chop and stop-and-chop techniques for cataracts with different degrees of nuclear density. PATIENTS AND METHODS: One hundred two eyes of 51 patients with bilateral senile cataract were included. Each eye was randomly assigned to have either phaco-chop or stop-and-chop nucleofractis during phacoemulsification. The groups were divided into two subgroups according to the nuclear density. The effective phacoemulsification time, endothelial cell density, and central corneal thickness were analyzed. RESULTS: The mean effective phacoemulsification time was similar between the groups in moderately dense nuclei (2.17 +/- 1.33 vs 1.33 +/- 1.05 seconds; P = .41). However, the phaco-chop technique required less effective phacoemulsification time than the stop-and-chop technique in dense nuclei (3.86 +/- 4.18 vs 6.70 +/- 5.43 seconds; P = .01). The endothelial cell loss and the central corneal thickness did not vary significantly between the groups. CONCLUSION: The phaco-chop technique requires lower ultrasound energy for nuclear management than the stop-and-chop technique in dense cataracts and the resulting endothelial loss was similar in both techniques.

Cytokine secretion by human mesenchymal stem cells cocultured with damaged corneal epithelial cells.

We have previously shown that mesenchymal stem cells (MSCs) reduced corneal inflammation and neovascularization in chemically-burned rat corneas in part through paracrine action. In order to identify the molecule(s) involved, we cocultured human MSCs in the following conditions, and examined the alterations in the cytokine secretion profile; (1) human peripheral blood mononuclear cells (hPBMCs), (2) chemically-damaged human corneal epithelial cells (hCECs), (3) hPBMCs/hCECs, (4) hMSCs, (5) hMSCs/hPBMCs, (6) hMSCs/hCECs, (7) hMSCs/hPBMCs/hCECs. We found that the levels of interleukin (IL)-6 and vascular endothelial growth factor (VEGF) by hMSCs markedly increased for hMSC/hCEC cocultures, and this elevation was further remarkable by the addition of hPBMCs. The hMSCs constitutively expressed transforming growth factor (TGF)-beta1, matrix metalloproteinase (MMP)-2, and thrombospondin-1. The secretion of MMP-9 by hCECs was significantly suppressed by hMSCs. Tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, and IL-10 were not detectable in any cultures. The data presented herein provide the candidate molecules mediating the MSC-mediated modulation of inflammation and angiogenesis in cornea.

The anti-inflammatory and anti-angiogenic role of mesenchymal stem cells in corneal wound healing following chemical injury.

To investigate the anti-inflammatory and anti-angiogenic effects of mesenchymal stem cells (MSC) in the chemically burned corneas, we mechanically removed the corneal epithelium of rats after 100% alcohol instillation. The rats were then randomized into four groups: fresh media, conditioned media derived from the MSC culture (MSC-CM), MSC applied topically to the damaged corneas for 2 hours immediately after the injury or MSC-CM applied either once or 3 times per day for 3 consecutive days. Corneal surface was evaluated every week. After 3 weeks, the corneas were stained with the hematoxylin-eosin, and the expression of interleukin (IL)-2, interferon (IFN)-gamma, IL-6, IL-10, transforming growth factor (TGF)-beta1, thrombospondin-1 (TSP-1), matrix metalloproteinase-2 (MMP-2), and vascular endothelial growth factor (VEGF) were analyzed. CD4+ cells were assessed in the corneas. We found that both MSC and three-time applied MSC-CM (1) reduced corneal inflammation and neovascularization, (2) decreased IL-2 and IFN-gamma, although increased IL-10 and TGF-beta1 as well as IL-6, (3) reduced the infiltration of CD4+ cells, and (4) upregulated the expression of TSP-1, although downregulated that of MMP-2. Interestingly, whereas three-time application of MSC-CM was partially effective, transplantation of MSC achieved a better outcome in suppressing corneal inflammation. The results of this study suggest that the anti-inflammatory and anti-angiogenic action of MSC in the chemically burned corneas might be mediated in part through paracrine pathways involving soluble factors such as IL-10, TGF-beta1, IL-6 and TSP-1.

Acute cell-mediated rejection in orthotopic pig-to-mouse corneal xenotransplantation.

BACKGROUND: To investigate the role of T cells and natural killer (NK) cells in mediating corneal xenograft rejection in a pig-to-mouse model. METHODS: Pig corneas were orthotopically transplanted into BALB/c, C57BL/6, nude, severe combined immunodeficiency (SCID), and NOD/SCID/gammac(null) (NOG) mice. Graft survival was clinically assessed by slit-lamp biomicroscopy and median survival times (MST) were calculated. The rejected grafts were histologically evaluated using antibodies against CD4, CD8, NK1.1, and F4/80. RESULTS: The pig corneal xenografts were acutely rejected by BALB/c and C57BL/6 mice (MST 9.0 days), while nude, SCID and NOG mice rejected pig corneas in a more delayed fashion (MST 16.0, 16.4, and 16.9 days, respectively). The majority of infiltrating cells found in rejected grafts in C57BL/6 mice were macrophages and CD4(+) T cells, while CD8(+) T cells and NK cells were rarely found. The grafts in nude mice had markedly decreased inflammatory infiltration with small numbers of macrophages and CD4(+) T cells. Infiltration was even more modest in grafts in SCID and NOG mice. CONCLUSIONS: T cells play an important role in acute rejection of pig corneal xenografts in mice, although acute rejection is not solely the result of T-cell-mediated immunity. NK cells are less likely to be involved in the rejection process.

Effects of white-to-white diameter and anterior chamber depth on implantable collamer lens vault and visual outcome.

PURPOSE: To investigate the effects of anterior chamber depth (ACD) and white-to-white (WTW) diameter on vault in eyes with implantable collamer lenses (ICL V4, STAAR Surgical AG) and to evaluate the effect of vault on visual outcomes and other biometric changes. METHODS: Twenty-eight eyes of 16 patients who underwent ICL implantation were retrospectively reviewed. Patients were divided into two groups (A1, A2) according to preoperative ACD (> or = 3.3 mm and < 3.3 mm, respectively), two groups (B1, B2) based on WTW diameter (> or = 11.55 mm and < 11.55 mm, respectively), and two groups (C1, C2) according to the difference of ICL diameter and sulcus length (> or = 0.25 mm and < 0.25 mm, respectively). Vault, endothelial cell density, and visual performance were compared between each set of groups. Correlations of vault with WTW diameter, ACD, and diametric difference of the ICL from the sulcus were analyzed. RESULTS: The high ACD and WTW groups showed significantly higher vaults (0.59 +/- 0.32 mm and 0.57 +/- 0.36 mm, respectively) than the low ACD and WTW groups (0.26 +/- 0.17 mm and 0.25 +/- 0.14 mm, respectively; P = .01 and .01), whereas the differences of diameter between the sulcus and ICL were not related to significant vault differences. The WTW diameter wascorrelated more closely to the vault than the ACD or sulcus diameter (r = 0.70, P < .001), whereas the vault difference did not affect visual quality or endothelial cell density. CONCLUSIONS: A high WTW diameter or ACD is likely to render a high vault, regardless of any difference in the ICL and sulcus diameters.

Preliminary effects of oral uridine on the ocular surface in dry eye patients.

We designed a randomized, double blinded, 3-months controlled prospective clinical study to investigate effects of oral uridine on the ocular surface in dry eye patients. Twenty-seven patients who diagnosed as dry eye with lower than 5 mm of wetting in the Schirmer strip, with corneal epithelial erosion and who completely followed-up till 3 months were enrolled. Corneal-conjunctival fluorescein staining, non-anesthetic Schirmer test, impression cytology, and Ocular Surface Disease Index (OSDI) were evaluated in the experimental and placebo groups at the baseline, 1 and 3 months after start of medication in a double blinded manner. Fluorescein stain score of the cornea was markedly decreased in oral uridine group compared to the placebo group at 3 months after medication (P=0.032, Mann-Whitney U test). The Schirmer wetting score for the oral uridine group was significantly increased (P=0.001, Wilcoxon signed rank test) at 3 months and its difference between two groups was statistically significant (P=0.030, Mann-Whitney U test). OSDI scores were significantly decreased at 1 and 3 months in treatment group. Oral uridine is effective in treatment of dry eyes.

DNA microarray-based gene expression profiling in porcine keratocytes and corneal endothelial cells and comparative analysis associated with xeno-related rejection.

Porcine to rat corneal xenotransplantation resulted in severe inflammation and rejection of the corneal stroma, whereas an allograft showed mainly endothelial cell-associated rejection. We, therefore, investigated and compared the gene expression between porcine keratocytes and corneal endothelial cells. RNA was isolated from primary cultured porcine or human keratocytes and porcine corneal endothelial cells. Gene expression was comparatively analyzed after normalization with microarray method using Platinum pig 13 K oligo chip (GenoCheck Co., Ltd., Ansan, Korea). Real-time polymerase chain reaction (PCR) was performed for C1R, CCL2, CXCL6, and HLA-A in porcine keratocytes and corneal endothelial cells. As a result, upregulated expression more than 2 folds was observed in 1,162 genes of porcine keratocytes versus porcine endothelial cells. Among the immune-regulatory genes, SEMA3C, CCL2, CXCL6, F3, HLA-A, CD97, IFI30, C1R, and G1P3 were highly expressed in porcine keratocytes, compared to porcine corneal endothelial cells or human keratocytes. When measured by real-time PCR, the expression of C1R, CCL2, and HLA-A was higher in porcine keratocytes compared to that in porcine corneal endothelial cells. In conclusion, the increased expression of C1R, CCL2, and HLA-A genes in porcine keratocytes might be responsible for the stromal rejection observed in a porcine to rat corneal xenotransplantation.

Rat allogeneic mesenchymal stem cells did not prolong the survival of corneal xenograft in a pig-to-rat model.

OBJECTIVE: Recent reports have demonstrated that mesenchymal stem cells (MSCs) can modulate/suppress immunologic responses through interactions with different immune cells. We performed this study in order to investigate the immunomodulatory effects of MSCs in corneal xenotransplantation. ANIMALS STUDIED: Pig and rat. PROCEDURES: We orthotopically transplanted pig corneas into rats and topically applied allogeneic rat MSCs to the corneas for 2 h immediately after transplantation. Graft survival was clinically assessed using slit-lamp biomicroscopy and the median survival time (MST) was calculated. The rejected grafts were histologically examined using antibodies against CD4, CD8, CD161, and CD68. The expression of IL-2, IL-6, IL-10, and IFN-gamma was also evaluated in the rejected grafts using an enzyme-linked immunosorbent assay. RESULTS: The survival of corneal xenografts was not significantly prolonged by MSC application (MST 10.5 days) compared with the controls (MST 9.67 days) (P = 0.4189). Histologically, the rejected grafts in both groups were massively infiltrated with neutrophils and macrophages. Some CD8+ T cells and rare NK cells were found in the rejected grafts. The levels of IL-6 and IL-10 were significantly increased in the rejected grafts from MSC-treated rats compared with the grafts from MSC-untreated rats. However, the levels of IL-2 and IFN-gamma were not different between the two groups. CONCLUSIONS: Topical application of allogeneic rat MSCs was ineffective in prolonging corneal xenograft survival in a pig-to-rat model.

Comparative observation of freeze-thaw-induced damage in pig, rabbit, and human corneal stroma.

OBJECTIVE: Although variations exist between species with respect to outcomes after cryopreservation, little is known about the differences in the susceptibility of the corneal stroma to cryoinjury. We performed this study to investigate freeze-thaw-induced damage in keratocytes and collagen in rabbit, pig, and human corneas. ANIMALS STUDIED: Rabbit, pig, and human. PROCEDURES: We prepared 250-microm-thick anterior stroma from rabbit, pig, and human corneas after scraping off the epithelium and endothelium. Each 250-microm-thick corneal stroma without epithelium was placed in a 50-mL tube, frozen with liquid N2 for 15 min and taken out to thaw rapidly at 37 degrees C. This procedure of rapid freezing and thawing was repeated three times. Differences between the species with respect to cells and collagen structures were examined using hematoxylin-eosin (H&E) staining, terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay, and transmission electron microscopy (TEM). We orthotopically transplanted the pig and rabbit corneal transplants after the triple freeze-thaw cycle into rabbit eyes and evaluated graft survival. RESULTS: On gross examination, rabbit corneas became opaque after the triple freeze-thaw procedure, while pig and human corneas remained transparent. Histologically, keratocytes were apoptotic on TUNEL assay and TEM in rabbit, pig, and human corneas. Collagen fibrils were fragmented and the arrangement of collagen fibrils was severely disturbed in rabbit corneas on H&E staining and TEM; collagen was well preserved in pig and human corneas. Rabbit corneal stroma underwent autolysis after transplantation, whereas the pig corneal stroma remained clear for 1 month. CONCLUSIONS: Our study showed that rabbit corneal stroma was more susceptible to freeze-thaw injury than pig and human corneas.

Histological differences in full-thickness vs. lamellar corneal pig-to-rabbit xenotransplantation.

To evaluate the differences in graft survival and histopathological characteristics between full-thickness and lamellar orthotopic corneal xenotransplantation in a pig-to-rabbit model, we orthotopically transplanted a full-thickness or the anterior half of a pig's cornea onto the OD of 16 rabbits. As a result, the median survival were 16.83 and 29.07 days for the full-thickness and lamellar xenografts, respectively (P = 0.0005). Histologically, the full-thickness corneal xenografts had massive infiltration by eosinophils, whereas the lamellar xenografts showed predominantly mononuclear infiltrates (P < 0.05). Given these preliminary findings, lamellar corneal xenografts in rabbits survived longer than the full-thickness xenografts and each type of graft demonstrated different rejection mechanisms.

Transforming growth factor-beta expression in rat eyes with mechanical debridement of corneal epithelium or epithelial flap.

PURPOSE: To compare corneal haze and transforming growth factor (TGF)-beta expression in rat eyes with mechanical debridement of corneal epithelium or a chemically induced epithelial flap. SETTING: Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea. METHODS: Sixty corneas from 60 Sprague-Dawley rats were treated in 1 of 4 ways using a 2.0 mm trephine: corneal epithelium mechanically removed (Group 1), central cornea exposed to 20% ethanol for 30 seconds (Group 2), corneal epithelial flap made by applying 20% ethanol for 30 seconds and flap amputated (Group 3), corneal epithelial flap repositioned after ethanol-assisted detachment of epithelium as in Group 3 (Group 4). Corneal haze was graded. The TGF-beta expression was measured in corneas and lacrimal glands using reverse transcription polymerase chain reaction and immunohistochemistry until day 30. Semiquantitative analysis was done in a density ratio of TGF-beta/beta-actin with image analyzer and densitometry. RESULTS: Corneal haze was more severe in Groups 1 and 3 than in Groups 2 and 4. By day 7, mRNA expression of TGF-beta2 and type II receptor in corneas had increased more in Groups 1 and 3 than in Groups 2 and 4. In lacrimal glands, only TGF-beta1 in Group 3 increased until day 7. In corneas, staining of both TGF-beta1 and beta2 increased, more prominently in Groups 1 and 3. Lacrimal gland staining was more intense in Groups 1 and 3. CONCLUSION: Well-positioned corneal epithelial flaps may decrease corneal haze by reducing expression of TGF-beta; inadvertent removal of an epithelial flap made by ethanol seems to exacerbate haze by increasing TGF-beta.

Clinical efficacy of amniotic membrane transplantation in the treatment of various ocular surface diseases.

PURPOSE: To investigate the efficacy of permanent amniotic membrane transplantation (AMT) for the treatment of various ocular surface diseases. METHODS: The medical records of 62 eyes from 58 patients who had undergone permanent AMT were reviewed. The amniotic patches were grafted for the treatment of neurotrophic ulcers (n=15), inflammatory corneal ulcers (n=15), scleral ulcers (n=11), painful bullous keratopathy (n=8) and pterygium as an adjuvant to a conjunctival autograft (n=13). Cryo-preserved or freeze-dried amniotic membrane (AM) were used. The overall success rate, the interval to epithelialization, pain-subsiding time, and complications were evaluated. The pain relief and the full epithelialization interval in the bullous keratopathy patients given the cryo-preserved AM were compared with those given the freeze-dried AM. RESULTS: The success rate in the patients with neurotrophic ulcer, inflammatory corneal ulcer, scleral ulcer and bullous keratopathy were 93.3%, 66.7%, 92.9% and 100%, respectively. A conjunctival autograft with AMT showed a 100% success rate without recurrence. The time to re-epithelialization was 24.4+/-24.2, 20.4+/-5.8, and 16.9+/-7.0 days in patients with neurotrophic, inflammatory and scleral ulcers, respectively (p=0.431). The pain relief interval in the cryo-preserved and freeze-dried AM group was 17.7 and 23.3 days, and the re-epithelialization interval was 29 and 22 days, respectively, which was insignificant. CONCLUSIONS: AMT has a high success in the treatment of neurotrophic, scleral ulcer, bullous keratopathy and pterygium with a low rate of complications but presented only partial success in the treatment of inflammatory corneal ulcers. The clinical efficacy of AMT was not related to the methods used to preserve the AM.