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Descemet's Stripping Only (DSO) is a surgical technique that utilizes the peripheral corneal endothelial cell (CEnC) migration for wound closure. Ripasudil, a Rho-associated protein kinase (ROCK) inhibitor, has shown potential in DSO treatment; however, its mechanism in promoting CEnC migration remains unclear. We observed that ripasudil-treated immortalized normal and Fuchs endothelial corneal dystrophy (FECD) cells exhibited significantly enhanced migration and wound healing, particularly effective in FECD cells. Ripasudil upregulated mRNA expression of Snail Family Transcriptional Repressor ( SNAI1/2 ) and Vimentin ( VIM ) while decreasing Cadherin ( CDH1 ), indicating endothelial-to-mesenchymal transition (EMT) activation. Ripasudil activated Rac1, driving the actin-related protein complex (ARPC2) to the leading edge, facilitating enhanced migration. Ex vivo studies on cadaveric and FECD Descemet's membrane (DM) showed increased migration and proliferation of CEnCs after ripasudil treatment. An ex vivo DSO model demonstrated enhanced migration from the DM to the stroma with ripasudil. Coating small incision lenticule extraction (SMILE) tissues with an FNC coating mix and treating the cells in conjunction with ripasudil further improved migration and resulted in a monolayer formation, as detected by the ZO-1 junctional marker, thereby leading to the reduction in EMT. In conclusion, ripasudil effectively enhanced cellular migration, particularly in a novel ex vivo DSO model, when the stromal microenvironment was modulated. This suggests ripasudil as a promising adjuvant for DSO treatment, highlighting its potential clinical significance.

Purpose: To determine whether ubiquinol improves mitochondrial function and cell viability in human donor corneal endothelial cells during hypothermic corneal tissue storage., Methods: Endothelial cell Descemet membrane tissues were treated with 10 μM ubiquinol, the reduced form of the antioxidant coenzyme Q10, for 5 days in Optisol-GS storage media before assaying for mitochondrial activity using extracellular flux analysis of oxygen consumption. In addition, endothelial cell Descemet membrane tissues were analyzed for cell viability using apoptosis and necrosis assays. Control tissues from mate corneas were treated with diluent only, and comparisons were analyzed for differences., Results: A total of 13 donor corneal tissues with a mean (SEM) preservation time of 11.8 days (0.4) were included for the analysis. Treatment with 10 μM ubiquinol increased spare respiratory capacity by 174% (P = 0.001), maximal respiration by 93% (P = 0.003), and proton leak by 80% (P = 0.047) compared with controls. Cells treated with ubiquinol had no significant change in cell necrosis or apoptosis., Conclusions: Preliminary testing in donor corneal tissue at specified doses indicates that ubiquinol may be a useful biocompatible additive to hypothermic corneal storage media that increases corneal endothelial cell mitochondrial function. Additional investigations are indicated to further study and optimize the dose and formulation of ubiquinol for use in preserving donor corneal tissue function during hypothermic storage.

BACKGROUND Alzheimer's disease (AD) is a degenerative disease that is characterized by massive neuron devastations in the hippocampus and cortex. Mild cognitive impairment (MCI) is the transitory stage between normality and AD dementia. This study aimed to investigate the melatonin induced effects on the lamina cribrosa thickness (LCT) of patients with MCI. MATERIAL AND METHODS The LCT data of patients with MCI were compared to LCT data of healthy controls. Subsequently, all MCI patients were randomly assigned into an experimental group (with melatonin treatment) or a placebo group (without any melatonin treatment). RESULTS The LCT of MCI patients decreased significantly compared with healthy controls. The univariate analysis showed that the lower the Mini Mental State Examination (MMSE) score (P=0.038; 95% CI: 0.876, -0.209), the smaller hippocampus volume (P=0.001; 95% CI: -1.594, -2.911), and the upregulated level of cerebrospinal fluid (CSF) T-tau (P=0.036; 95% CI: 2.546, -0.271) were associated significantly with the thinner LCT in MCI patients. There were 40 patients in the experimental group and 39 patients in the placebo group. The mean age of the experimental group was not significantly different from the placebo group (66.3±8.8 versus 66.5±8.3; P>0.05). The LCT and hippocampus volume of the melatonin treated group were significantly larger compared with the placebo group (P<0.001). On the other hand, the CSF T-tau level of the melatonin treated group was significantly lower compared with the untreated group (P<0.001). CONCLUSIONS LCT assessment might allow early diagnosis of MCI. Dietary melatonin therapy could provide an effective medication for MCI patients with LCT alterations.

Corneal endothelial cell cultures have a tendency to undergo epithelial-to-mesenchymal transition (EMT) after loss of cell-to-cell contact. EMT is deleterious for the cells as it reduces their ability to form a mature and functional layer. Here, we present a method for establishing and subculturing human and sheep corneal endothelial cell cultures that minimizes the loss of cell-to-cell contact. Explants of corneal endothelium/Descemet's membrane are taken from donor corneas and placed into tissue culture under conditions that allow the cells to collectively migrate onto the culture surface. Once a culture has been established, the explants are transferred to fresh plates to initiate new cultures. Dispase II is used to gently lift clumps of cells off tissue culture plates for subculturing. Corneal endothelial cell cultures that have been established using this protocol are suitable for transferring to biomaterial membranes to produce tissue-engineered cell layers for transplantation in animal trials. A custom-made device for supporting biomaterial membranes during tissue culture is described and an example of a tissue-engineered graft composed of a layer of corneal endothelial cells and a layer of corneal stromal cells on either side of a collagen type I membrane is presented.

Background: Descemet's membrane detachment (DMD) is a rare complication after ocular chemical injury and its pathogenesis remains unclear. In this study, we reported two cases of DMD with traction demonstrated on Anterior segment optical coherence tomography (AS-OCT)., Case Presentation: Two patients sustained ocular chemical injury with 50% sodium hydroxide. In both cases, AS-OCT revealed detached Descemet's membrane that was adherent to the underlying iris tissue in the inferior quadrant at 45 days and 34 days after the injury respectively. The first case received intracameral tamponade with 12% C 3 F 8 gas and the second case received corticosteroid and sodium chloride 5% eye drops. However, DMD persisted in both cases., Conclusions: The atypical features of DMD on anterior segment optical coherence tomography in our cases suggested the presence of an inflammatory component caused adhesions and traction of iris to Descemet's membrane and prevented reattachment of DMD even with gas tamponade.

The purpose of this study was to evaluate the effects of vital dyes on human Descemet's membranes (DMs) and endothelia. DMs of 25 human cadaveric corneas with research consent were treated with dyes routinely used in Descemet membrane endothelial keratoplasty (DMEK), 0.05% Trypan blue (TB) or a combination of 0.15% Trypan blue, 0.025% Brilliant blue and 4% Polyethylene glycol (commercial name Membrane Blue Dual; MB). The effects of these two dyes on (i) endothelial cell viability, (ii) DM mechanical properties as assessed by atomic force microscopy, and iii) qualitative DM dye retention were tested for two varying exposure times (one or four minutes). No significant differences in cell toxicity were observed between treatments with TB and MB at the two different exposure times (P = 0.21). Further, both dyes led to a significant increase in DM stiffness: exposure to TB and MB for one minute increased the apparent elastic modulus of the DM by 11.2% (P = 8*10-3) and 17.7%, respectively (P = 4*10-6). A four-minute exposure led to an increase of 8.6% for TB (P = 0.004) and 13.6% for MB (P = 0.03). Finally, at 25 minutes, the dye retention of the DM was considerably better for MB compared to TB. Taken together, a one-minute exposure to MB was found to improve DM visibility compared to TB, with a significant increase in DM stiffness and without detrimental effects on endothelial cell viability. The use of MB could therefore improve (i) visibility of the DM scroll, and (ii) intraoperative unfolding, enhancing the probability of successful DMEK surgery.

Purpose: To investigate the adhesive and stiffness properties of prestripped Descemet membrane endothelial keratoplasty (DMEK) lenticules in different preservation conditions (with and without dextran)., Methods: The study included 3 conditions: (C1) tissues collected from tissue culture media (TCM), stripped and preserved in TCM; (C2) tissues collected from transport media (TM) (TCM supplemented with 6% dextran T-500), stripped and preserved in TM; and (C3) tissues collected from TCM, stripped and preserved in TM. Using a hinge, 9.5-mm stripped DMEK lenticules were restored back on the stroma and preserved for 4 days at room temperature (RT) in different conditions as above. Nine tissues, 3 from each condition, were used to check the adhesive (fibronectin, laminin, and vitronectin) and elastic properties (fibrillin, elastin, and collagen VI) using different antibodies. Six tissues, 2 from each condition, were used to check the stiffness properties after preservation using atomic force microscopy (AFM) nanoindentation method., Results: On the Descemet membrane, fibronectin was strongly expressed in C2 and C3, whereas laminin was intense in C2 postpreservation. Vitronectin was expressed in all the conditions. Elastic proteins were not expressed in either of the conditions apart from collagen VI, which was expressed on the posterior stroma. Atomic force microscopy showed higher stiffness in C3 and an insignificant but lower rigidity in C2 as compared to C1., Conclusions: The tissues from C2 showed expression of adherent proteins and lower stiffness. Dextran may be suitable in preservation of DMEK grafts before and after preparation. Less stiff tissues may help reduce manipulations required in the recipient eye during DMEK surgery.

Purpose: Trypan blue (TB) is used for visualization of the endothelium-Descemet membrane graft during Descemet membrane endothelial keratoplasty (DMEK). However, TB is assumed to have a dose-dependent toxic effect on the corneal endothelium. We retrospectively compared a lutein/zeaxanthin and Brilliant Blue (LZ/BB)-based dye for preparation and transplantation of the graft in DMEK to TB., Methods: In 20 patients, a dye composed of 1% LZ /0.025% BB was used, and in 22 patients, 0.06% TB was used for graft visualization in DMEK. We evaluated the rebubbling rate, best spectacle-corrected visual acuity (BSCVA), central corneal thickness (CCT), and endothelial cell density (ECD) before and 3 and 6 months after transplantation., Results: Staining of endothelium-Descemet membrane with LZ/BB was faint but sufficient. There was no significant difference between both groups, except in CCT after 3 months, which was lower in the LZ/BB group (P = 0.02). In the LZ/BB group, BSCVA improved from 0.48 ± 0.39 before DMEK to 0.19 ± 0.09 after 6 months (P < 0.05) (20% rebubbling rate). Donor ECD decreased from 2735 ± 259 cells/m preoperatively to 1876 ± 316 cells/mm (P < 0.0001) at 6 months (31.4%). CCT decreased from 642 ± 130 μm preoperatively to 519.8 ± 38 μm (P < 0.0001) at 6 months. In the TB group, BSCVA improved from 0.43 ± 0.27 to 0.17 ± 0.14 (P = 0.0003) at 6 months (30% rebubbling rate). ECD decreased from 2825 ± 263 to 1777 ± 302 cells/mm (P < 0.0001) after 6 months (36.3%), CCT from 638 ± 48 μm preoperatively to 531 ± 48 μm (P < 0.0001) at 6 months., Conclusions: LZ/BB-based dyes are suitable for DMEK with outcomes comparable to TB. However, available formulas result in faint staining, discouraging their routine use in donors with assumed difficult preparation.

Purpose: To evaluate the effect of trypan blue on the elastic property of Descemet membrane (DM) by atomic force microscopy., Methods: Human corneas (n = 10) were obtained from the Illinois Eye Bank (Chicago, IL). The DM was isolated and divided into two halves, one half was stained with ophthalmic trypan blue (Vision Blue, 0.06%, DORC International), whereas the unstained other half served as control. The DM samples were then tested using the atomic force microscope. Data were analyzed using the Hertz model for the evaluation of the Young modulus of elasticity., Results: Atomic force microscopy showed higher cantilever deflection on trypan blue-stained DM compared with control, and the difference was statistically significant (P = 0.03). Force-distance curve analysis also revealed a statistically significant increase in the Young modulus of elasticity in the trypan blue-stained samples (10.5 ± 1.4 kPa) compared with the control (5.8 ± 0.8 kPa), (P < 0.0001)., Conclusions: Our results suggest that trypan blue may decrease DM elasticity and consequently increase its stiffness. This may influence the graft adherence when used for endothelial keratoplasty.

Descemetʼs membrane detachment (DMD) is a rare complication following cataract and glaucoma surgery as well as lamellar graft procedures. DMD can lead to blurry vision, halos and severe visual loss. Clinically, when there is a large central detachment, a double anterior chamber is seen to form. In this scenario, surgical repair may be needed. Repair of localised DMD may be achieved by injection of gases such as perfluoropropane (C3F8) and sulfurhexafluoride (SF6) or sterile air. The effect of a functioning Baerveldt tube in situ during these injections has not been reported. We report a case of DMD repair in an eye with a Baerveldt aqueous shunt.

A 65-year-old woman with iridocorneal endothelial syndrome and a history of Ahmed glaucoma drainage (AGD) tube implantation underwent Descemet stripping automated endothelial keratoplasty (DSAEK) in her right eye. During the procedure, filling the anterior chamber with air was quite difficult due to escape of air via the AGD tube and a complete air fill of the anterior chamber could only be managed after multiple attempts. On operation night, there was no air left in the anterior chamber. On postoperative day 1, graft detachment was determined by slit-lamp biomicroscopy. For rebubbling, sulfur hexafluoride (SF(6)) 20 % was injected into the anterior chamber. Two days later, there was still some SF(6) in the anterior chamber and the graft was completely attached. At postoperative week 2, visual acuity was 2/10. SF(6) use may be considered for DSAEK in cases of previous AGD tube implantation history due to its potential for longer duration in order to obtain a better tamponade with the bubble due to its expanding nature.

Purpose: To describe the clinical course, ultrasonographic and confocal microscopic findings in a patient who developed a large Descemet membrane (DM) detachment that resolved spontaneously after ocular sodium cyanide injury., Methods: Case report., Results: The patient presented with severe corneal stroma edema, a large detachment of DM, iritis, and anterior subcapsular lens opacity in the left eye caused by contact with 5% sodium cyanide. The ultrasound biomicroscopic and in vivo confocal microscopic examination exhibited the configuration of the DM detachment and extensive damage of corneal cells. Although no viable endothelial cells were observed with in vivo confocal microscopy, the DM spontaneously reattached 11 days after injury, coincident with increased intraocular pressure. However, persistent corneal edema and iris atrophy were observed 6 months after DM reattached., Conclusions: Sodium cyanide can cause severe injuries to the cornea and the anterior segment. Extensive DM detachment may resolve spontaneously despite the absence of viable endothelial cells.

Vascular endothelial growth factor A (VEGF-A) is a promoter of neovascularization and thus a popular therapeutic target for diseases involving excessive growth of blood vessels. In this study, we explored the potential of the disaccharide sucrose octasulfate (SOS) to alter VEGF165 diffusion through Descemet's membrane. Descemet's membranes were isolated from bovine eyes and used as a barrier between two chambers of a diffusion apparatus to measure VEGF transport. Diffusion studies revealed a dramatic increase in VEGF165 transport in the presence of SOS, with little diffusion of VEGF165 across the membrane over a 10-h time course in the absence of SOS. Diffusion studies with VEGF121, a non-heparin binding variant of VEGF, showed robust diffusion with or without SOS. To determine a possible mechanism, we measured the ability of SOS to inhibit VEGF interactions with extracellular matrix (ECM), using cell-free and cell surface binding assays. Binding studies showed SOS had no effect on VEGF165 binding to either heparin-coated plates or endothelial cell surfaces at less than mg/ml concentrations. In contrast, we show that SOS inhibited VEGF165 binding to fibronectin in a dose dependent manner and dramatically accelerated the rate of release of VEGF165 from fibronectin. SOS also inhibited the binding of VEGF165 to fibronectin-rich ECM deposited by vascular smooth muscle cells. These results suggest that fibronectin-rich extracellular matrices serve as barriers to VEGF165 diffusion by providing a network of binding sites that can trap and sequester the protein. Since the content of Descemet's membrane is typical of many basement membranes it is possible that they serve throughout the body as formidable barriers to VEGF165 diffusion and tightly regulate its bioavailability and distribution within tissues., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: Corneal transplantation has rapidly evolved from full-thickness penetrating keratoplasty (PK) to selective tissue corneal transplantation, where only the diseased portions of the patient's corneal tissue are replaced with healthy donor tissue. Descemet's membrane endothelial keratoplasty (DMEK) performed in patients with corneal endothelial dysfunction is one such example where only a single layer of endothelial cells with its basement membrane (10-15 µm in thickness), Descemet's membrane (DM) is replaced. It is challenging to replace this membrane due to its intrinsic property to roll in an aqueous environment. The main objective of this study was to determine the effects of fibrin glue (FG) on the biomechanical properties of DM using atomic force microscopy (AFM) and relates these properties to membrane folding propensity., Methodology/principal Findings: Fibrin glue was sprayed using the EasySpray applicator system, and the biomechanical properties of human DM were determined by AFM. We studied the changes in the "rolling up" tendency of DM by examining the changes in the elasticity and flexural rigidity after the application of FG. Surface topography was assessed using scanning electron microscopy (SEM) and AFM imaging. Treatment with FG not only stabilized and stiffened DM but also led to a significant increase in hysteresis of the glue-treated membrane. In addition, flexural or bending rigidity values also increased in FG-treated membranes., Conclusions/significance: Our results suggest that fibrin glue provides rigidity to the DM/endothelial cell complex that may aid in subsequent manipulation by maintaining tissue integrity.

Purpose: To describe an enzymatic technique that facilitates air separation of Descemet's membrane from the corneal stroma., Methods: Fresh human corneoscleral tissue was mounted on an artificial anterior chamber. In a control group, air was injected into the stroma. A second group received a stromal injection of 2.5 mg/mL collagenase type 2 in balanced salt solution that was left in the stroma for 1 hour and 15 minutes. A third group received an injection of 2.5 mg/mL collagenase type 2 in balanced salt solution followed 1 hour and 15 minutes later by an injection of air into the stroma. All injections were performed with a 27-gauge needle into the deep stroma without penetrating Descemet's membrane. Anterior segment optical coherence tomography (AS-OCT), histologic examination, and electron microscopy of the junction between the stroma and Descemet's membrane were performed. The trypan blue exclusion and TUNEL assays were used to study endothelial cell viability after collagenase incubation., Results: Injection of air or collagenase into the deep corneal stroma did not result in a reproducible separation of the stroma-Descemet's junction. In contrast, the stroma was easily and reproducibly separated from Descemet's membrane with a combination of intrastromal collagenase and air injection. The separation was confirmed by using light and electron microscopy. The cleavage plane seemed to be located between the junction of the posterior stroma and the anterior banded layer of Descemet's membrane. Trypan blue staining demonstrated the viability of endothelial cells after collagenase incubation. TUNEL assay confirmed excellent viability after collagenase+air separation., Conclusions: This technique facilitates the separation of Descemet's membrane from the stroma without affecting endothelial cell viability.

Purpose: To report a case of presumed bilateral corneal copper deposition secondary to oral contraceptive use., Methods: A 23-year-old woman was referred for evaluation of bilateral corneal opacities. The location of the deposits deep in Descemet's membrane and appearance made copper deposition a likely consideration., Results: Subsequent laboratory results revealed an elevated serum copper level (189 μg/dL). Other causes of cupremia were subsequently ruled out, and the patient's corneal copper deposition was attributed to her oral contraceptive use. With cessation of the oral contraceptive, her serum copper levels normalized, but the corneal deposits remained after 5 months of follow up., Conclusion: To our knowledge, we report the first case in the ophthalmic literature of presumed corneal copper deposition in the setting of oral contraceptive use. It is important to recognize the corneal findings associated with copper deposition, because it may lead to the diagnosis and treatment of other serious systemic conditions causing elevated serum copper levels.

Purpose: To document two cases of corneal pigmented rings and hypercupremia associated with estrogen-based oral contraceptive use. Other causes of corneal pigment rings including Kayser-Fleischer rings and the previously documented association of estrogens and hypercupremia are discussed., Case Reports: Two healthy female patients presenting to a general optometric practice for routine examinations were found to have bilateral bluish-green corneal deposits at the level of endothelium/Descemet's membrane. The deposits were predominately in the inferior midperiphery in both patients, but formed a complete ring 3 years after initial presentation in one. Both patients were found to have abnormally elevated serum copper and elevated ceruloplasmin levels, and both were taking estrogen-based oral contraceptives. Serum copper levels returned to normal levels soon after cessation of the oral contraceptives, and subsequently re-elevated when a different oral contraceptive agent was tried. Although the pigment rings appeared different from typical Kayser-Fleischer rings, both patients were referred to gastroenterologists to rule out Wilson's disease., Conclusions: This is believed to be the first report of corneal pigment deposition and hypercupremia associated with oral contraceptive use. Recognition of these potential side effects by eye care practitioners and prescribing physicians may spare patients the expense and morbidity risk of unnecessary medical testing. Further research is needed to determine the exact nature of the deposits (presumed to be a copper compound), and whether it may be accumulating to dangerous levels in other body tissues as in Wilson's disease.

We examined changes in the ultrastructure and localization of major extracellular matrix components, including 5 types of collagen (type I, III, IV, VI, and VIII), laminin, fibronectin, and heparan sulfate proteoglycan in Descemet's membrane of the cornea of diabetic GK rats. In the cornea of diabetic GK rats, more long-spacing collagen fibrils were observed in Descemet's membrane than in the membrane of the nondiabetic Wistar rats. Both GK and Wistar rats showed an age-dependent increase in the density of the long-spacing collagen. Immunoelectron microscopy showed that type VIII collagen was localized in the internodal region of the long-spacing collagen, which was not labelled by any of the other antibodies used. The antidiabetic agents nateglinide and glibenclamide significantly suppressed the formation of the long-spacing collagen in the diabetic rats. Long-spacing collagen would thus be a useful indicator for studying diabetic changes in the cornea and the effect of antidiabetic agents.

Purpose: To report a case of Descemet membrane detachment (DMD) after cataract surgery in an operated case of deep anterior lamellar keratoplasty (DALK)., Methods: Phacoemulsification surgery with intraocular lens implantation was performed in the left eye of a 65-year-old woman who had previously undergone DALK. DMD was noted intraoperatively, for which intracameral injection of air was done at the end of surgery. On the first postoperative day, DMD was seen, and hence, intracameral 20% sulfur hexafluoride (SF(6)) gas was injected. Because the DMD did not resolve, intracameral 14% C(3)F(8) gas was injected on the seventh postoperative day., Results: At the 3-week follow-up, complete resolution of DMD was seen., Conclusions: DMD that occurs during phacoemulsification in a case that has previously undergone DALK can be effectively and safely resolved using intracameral C(3)F(8) gas injection.

Purpose: To present clinical findings of a cluster of cases of toxic anterior segment syndrome (TASS) after uneventful phacoemulsification cataract surgery., Setting: Department of Ophthalmology, Akdeniz University, Antalya, Turkey., Methods: Six eyes of 6 patients developed TASS after uneventful phacoemulsification cataract surgery with implantation of a 3-piece acrylic IOL performed by 2 ophthalmologists on the same day. Clinical findings included corneal edema, Descemet's membrane folds, anterior chamber reaction, fibrin formation, and irregular, dilated, and unreactive pupils., Results: Glutaraldehyde 2% solution was used inadvertently by the operating room staff who cleaned and sterilized reusable ocular instruments before autoclaving. None of the affected corneas improved. Additional surgical procedures were required and included penetrating keratoplasty, trabeculectomy, and glaucoma tube implantation., Conclusions: Glutaraldehyde in concentrations generally used for cold sterilization is highly toxic to the corneal endothelium. The operating room staff involved in sterilizing instruments should be well educated about and careful to follow the protocols to properly clean and sterilize reusable ocular instruments.

Purpose: To report an unusual complication of treatment in the case of a Descemet's membrane detachment., Methods: Observational case report., Results: A 79-year-old woman presented for elective cataract surgery. Ocular risk factors identified preoperatively included moderately shallow anterior chambers bilaterally, previously treated with bilateral YAG peripheral iridotomies. After a clear corneal section during phacoemulsification, large Descemet's tears on introducing the micro finger and phaco probe were noticed. Conversion to an extracapsular technique was necessary because of poor view. Similar peroperative Descemet's detachments were noticed in the contralateral eye during phacoemulsification by a senior surgeon a year later. Postoperatively, the Descemet's detachments were managed by intracameral SF6 and later C3F8 gas. A few weeks later, a fine haze was noticed under the anterior surface of the intraocular lens (IOL). Corneal edema persisted and corneal decompensation ensued. Both eyes needed penetrating keratoplasties. The right eye needed an IOL exchange due to IOL haze., Conclusions: In this case the SF6 or C3F8 gas may have produced the unexpected effect of an anterior IOL haze. The mechanism of this phenomenon is unknown. To the knowledge of the authors, this effect has not been observed previously with SF6 or C3F8 gas. This haze was visually significant and required an IOL exchange. To the knowledge of the authors this is the first report of this nature. The authors advise caution when using intracameral SF6 or C3F8 gas for repair of Descemet's membrane detachment with this type of IOL.

Purpose: To report cases of ocular argyrosis that developed after long-term self-application of commercially available eyelash tint., Design: Observational case series., Methods: Case review, clinicopathologic analysis, and literature review., Results: Three patients developed ocular argyrosis after the long-term self-application of Revlon Professional Roux Lash and Brow Tint (Colomer USA Corp, New York, New York, USA). Clinical evaluation revealed various degrees of silver deposition on the upper eyelid, lid margin, caruncle and conjunctiva, and diffuse Descemet's membrane deposits. In one case, histologic examination demonstrated silver deposition in the basement membrane and superficial substantia propria of the conjunctiva., Conclusions: Argyrosis can occur after long-term application of readily available eyelash tints, and the deposition of silver may be permanent. In certain circumstances, conjunctival argyrosis may simulate benign and malignant lesions, including conjunctival melanoma. These products should only be applied by trained cosmetologists.

Purpose: To demonstrate the effectiveness and safety of using viscoadaptive viscoelastics in deep lamellar keratoplasty (DLKP) for keratoconus., Methods: A nonrandomized, comparative, interventional case series was performed on 12 eyes of 10 consecutive keratoconus patients without a history of acute hydrops. Patients were treated with DLKP using ophthalmic viscosurgical devices (OVDs) to dissociate Descemet membrane (DM) from the stroma before suturing of the donor cornea. Eight eyes were operated using Viscoat (dispersive), and 4 eyes were operated using Healon V (viscoadaptive)., Results: Six out of 8 eyes in the Viscoat group were successfully treated, and 2 eyes were converted to PKP because of tears in the DM. Another 3 eyes had double chambers as a result of perforations or tears in DM, which were treated by injecting air into the anterior chamber. All 4 eyes in the Healon V group were successfully operated, with 1 case with microperforation of DM during suturing. Healon V offered better control of the area to be dissociated and served as a pseudostroma that protects the exposed DM while the overlying stroma is maneuvered., Conclusion: Healon V is a valuable tool for performing DLKP in difficult cases such as keratoconus.

Objective: To describe a patient who developed a Descemet membrane detachment after hydrogen peroxide injury with successful reattachment by intracameral injection of sulfur hexafluoride gas., Methods: Case report., Results: The right eye of a 40-year-old man was exposed to 35% hydrogen peroxide. This resulted in a central corneal epithelial defect, corneal edema, a localized detachment of Descemet membrane, and a gas bubble between the posterior corneal stroma and Descemet membrane. The Descemet membrane detachment persisted after reabsorption of the gas bubble. Successful reattachment of Descemet membrane was achieved with injection of 0.15 mL of 20% sulfur hexafluoride gas into the anterior chamber., Conclusion: Hydrogen peroxide ocular injury may cause Descemet membrane detachment, and successful reattachment may be achieved with intracameral injection of 20% sulfur hexafluoride gas.

Objective: To analyze the possible causes of Descemet's membrane detachment (DMD) and the treatment and outcome of patients after cataract surgery., Design: Retrospective noncomparative interventional case series., Participants: Fifteen eyes of 12 patients., Methods: We reviewed clinical data on 15 eyes of 12 patients with nonscrolled DMD after cataract surgery who presented to the Cornea Service at Wills Eye Hospital from 1986 to 2001. Institutional review board/ethics committee approval was obtained., Main Outcome Measures: Visual acuity and reattachment of Descemet's membrane., Results: Cataract procedures involved nine clear-corneal eyes, four limbal incisions, one trabeculectomy/combined phacoemulsification, and one extracapsular cataract extraction. From 1986 to 1990, we had 1 patient; from 1991 to 1995, no patients; and from 1996 to 2001, 11 patients (including all clear-corneal eyes). Of the 15 eyes, 8 resolved with medical treatment alone, with a mean time to resolution of 9.8 weeks. One patient was lost to follow-up while improving on medical treatment, and another required a penetrating keratoplasty (PK) after medical treatment failed. Five eyes received anterior-chamber SF(6) gas injection. Of these eyes, three DMDs resolved, one underwent repeated injection (not improving after 10 weeks), and another required a PK., Conclusions: Referrals for DMD seem to be increasing. This may be explained by the increase in clear-corneal cataract procedures. Medical treatment seems to be adequate in many cases and may be appropriate initial therapy. When needed, SF(6) gas injection may also be successful, but not in all cases.

Purpose: To describe corneal complications in three patients following abuse of topical anesthetics., Materials and Methods: We describe one case with bilateral corneal perforation, another with unilateral corneal perforation and a third case of chronic keratitis following excessive use of topical anesthetics., Results: Two patients continued to instill topical anesthetic drops despite all recommendations to stop. The result was a bilateral corneal perforation in the first case and a large unilateral descemetocele in the second. The third patient who had chronic toxic keratitis discontinued the anesthetic drops and after the appropriate treatment the cornea returned to normal. Corneal grafting and conjunctival flaps were used to seal the corneal perforation but the long-term anatomical and functional results were very poor., Conclusions: The initial presentation of this rare clinical entity creates difficulties in reaching a correct diagnosis. A presumed acanthamoeba keratitis is the first choice among many similar conditions. Thus abuse of topical ocular anesthetic drops should be included in the differential diagnosis of cases of chronic keratitis as it may masquerade as acanthamoeba keratitis. A current or past history of psychiatric and mental disorders or psychoactive substance abuse is important in the diagnosis. Functional and anatomical results after appropriate treatment are usually poor. Psychiatric counselling is extremely helpful and is in fact mandatory in the management of these patients.

Purpose: To describe a case in which the recognition by the ophthalmologist of Kayser-Fleischer rings played a crucial role in the diagnosis of Wilson disease (hepatolenticular degeneration)., Design: Interventional case report., Methods: An 18-year-old woman was found to have bilateral peripheral golden brown pigment deposits at the level of the Descemet membrane consistent with Kayser-Fleischer rings. She initially denied systemic symptoms., Results: The serum cerumoplasmin level of the patient was normal. Liver function tests were also normal. Further evaluations with 24-hour urine copper assay and liver biopsy were positive for Wilson disease. She underwent anticopper therapy and, 6 months later, reported improved concentration and balance. No appreciable change occurred in the Kayser-Fleischer rings., Conclusion: Wilson disease occurs when a defective copper-transporting enzyme in the liver results in toxic copper accumulation in multiple organs. Because of the insidious nature of the disease, patients may not seek medical attention until severe irreversible damage has occurred. By diagnosis of Kayser-Fleischer rings, ophthalmologists may play a critical role in the early recognition and proper evaluation of such patients.

An unusual case of spontaneous corneal perforation of acute hydrops in the left eye of a 21-year-old man is presented. The patient had a history of atopic diseases. To evaluate the status of the other eye, corneal topographic analysis was performed. This confirmed a subclinical keratoconus in the fellow eye and the association with atopy, eye rubbing, and rapid progression of the ectasia leading to perforation.

Nd:YAG laser was used to disrupt Descemet's membrane in rabbits in order to provoke the hypothetical release of angiogenic activity without a significant traumatic inflammation. Corneal vascularization was elicited only with simultaneous administration of heparin, which alone was unable to initiate the growth of new blood vessels. It is probable that basic fibroblast growth factor (bFGF) was released from its depot in Descemet's membrane and its critical concentration was saved by heparin. The importance of Descemet's membrane is highlighted by the fact that a similar lesion of midstroma could not induce angiogenesis even if aided by heparin. However, some other mechanisms cannot be ruled out, as bFGF acts in paracrine and amacrine mode only.

Purpose: To assess whether changes in lactate dehydrogenase (LDH) activity, as a marker of cell damage, could be detected in corneal stroma and corneal epithelium after toxicity measurements using the enucleated eye test (EET)., Methods: The corneal surface of isolated bovine eyes was continuously wetted with commercial balanced salt solution (BSS) over 4 h at 37 degrees C and central corneal thickness (CCT) was measured. Initial 5-min challenges were made with dilute solutions of benzalkonium chloride (up to 0.032%) or NaOH (up to 0.4 M). The residual LDH activity in the corneal epithelium and corneal stroma were then assessed., Results: Dose-dependent increases in CCT of up to 70% were measured. A strong correlation (r = -0.961) was found between increases in CCT and decreases in stromal LDH activity, but the correlation was much less (r = -0.512) for epithelial LDH activity., Conclusions: LDH activity can be used as one marker for cell integrity in the corneal stroma and epithelium, although dose-dependent correlations may not be high.

It has been hypothesized that Maillard reaction products form in basement membranes during aging and may affect protein turnover. The purpose of this study was to localize Maillard reaction products in intact lens capsules and Descemet's membranes by immunoelectron microscopy to determine whether Maillard products accumulated with age and whether basement membrane thickness increased to a similar degree. The monoclonal antibodies antiglucitollysine and antipyrraline were employed to detect the products in native and glucose-treated bovine basement membranes. The content of basic amino acids, furosine, and fluorophores (370/440), as well as resistance to trypsin digestion showed that the basement membranes formed significant quantities of Maillard products when incubated with 200 mM glucose in vitro (P < 0.05). Likewise, incubation in 200 mM glucose resulted in at least a 4-fold increase in immunoreactivity (P < 0.001). Native basement membranes increased in thickness more than 2-fold with age (P < 0.001). Immunoreactivity varied similarly in that bound antiglucitollysine increased approx. 2-fold and antipyrraline approx. 3-fold in old vs. young basement membranes, but these differences were significant only in pyrraline immunoreactivity in the lens capsule (P < 0.01). Advanced products other than pyrraline may accumulate in Descemet's membrane since significant increases in fluorescence and resistance to trypsin were noted. These data suggest that the Maillard reaction may, to a small degree, contribute to basement membrane thickening.

We describe a case of accidental injection of sodium hyaluronate (Healon) anterior to Descemet's membrane that caused the membrane to become almost completely detached. The patient eventually underwent penetrating keratoplasty, permitting histopathologic study of the detachment. Sodium hyaluronate globules in the space between the posterior stroma and Descemet's membrane were demonstrated by light and electron microscopy. In addition, 111 consecutive cases of Descemet's membrane detachment identified pathologically were reviewed to identify potential predisposing risk factors and determine corneal pathologic changes. A history of previous intraocular surgery was present in 89 (80%) of the cases; cataract surgery, the most common, had occurred in 52 (58%). Frequent associated corneal pathologic findings were bullous keratopathy in 48 (43%) of the specimens, and scarring and vascularization in 33 (29.7%). In one case that was identified and studied histopathologically, a 90% detachment of Descemet's membrane was noted clinically following the reformation of the anterior chamber with sodium hyaluronate. We conclude that in the cases of Descemet's membrane detachment that came to pathologic examination, intraocular surgery was a major predisposing risk factor. Corneal pathologic changes, which were common, possibly masked the clinical diagnosis of Descemet's membrane detachment in some cases.

A 39-year-old woman developed a painful, red eye immediately following oral surgery associated with preoperative preparation of her face with the antiseptic, Hibiclens. Epithelial and stromal edema was observed 2 weeks after surgery and progressed to diffuse bullous keratopathy. This led to penetrating keratoplasty 10 months later. Light and electron microscopic findings of the cornea included epithelial edema with bullous changes, marked loss of keratocytes, a thickened Descemet's membrane, and an attenuated, disrupted endothelial cell layer. These findings demonstrate the corneal damage that may occur following ocular exposure to Hibiclens.

Several growth factors have been evaluated for their effects on corneal wound healing but few studies have yet demonstrated an acceleration of endothelial repair in vivo. Mesodermal Growth Factor (MGF) was tested in vivo by making standardized freeze wounds in cat corneas and immediately injecting one of four concentrations of MGF in sterile phosphate buffered saline (PBS), or PBS alone, into the anterior chamber. Seven days later, the animals were sacrificed and the corneas excised and stained. Descemet's membrane and endothelium were dissected and mounted onto glass slides. The wound areas were photographed, measured and compared statistically. Those cats receiving the three lowest doses of MGF had significantly smaller wounds than controls (p less than 0.05).

Unlabelled: The endothelial covering of experimental wounds on the posterior corneal surface has been studied in organ culture experiments. Defects involving the Descemet's membrane were produced, in addition to pure endothelial defects. The influence of foetal calf serum (FCS) on the healing process was examined. Wounds including the Descemet's membrane, about 1-2 X 3 mm, were not covered by cells after 12 days in FCS free medium. Such wounds were covered by endothelium after 6 days when cultivated in medium containing 10% FCS, and partly covered in 1% FCS. Pure endothelial defects, 4 mm in diameter, were cell-covered within 3-4 days irrespective of the presence of FCS., Conclusion: the presence of FCS is required for the healing of defects involving the Descemet's membrane, and not required for the healing of pure endothelial defects.

The localization of anionic sites on the surface of corneal endothelium was investigated using colloidal nickel. The distribution of the binding sites of colloidal nickel along the cell surface was examined with the scanning electron microscope. The application a special detector of high sensitivity reflection allows to register a composed contrast determined by colloidal nickel. Colloidal nickel is bound with the surface of endothelium in areas of cell junctions only. A 1 X 10(-4)% sol. adrenaline injection into the anterior rabbit eye chamber in vivo changed the distribution of colloidal nickel. These findings demonstrate that colloidal nickel allows to mark the anionic sites on the cell surface for scanning electron microscopic studies.

We report a case in which, in an attempt to reform a flat anterior chamber, hyaluronic acid inadvertently was injected between Descemet's membrane and the corneal stroma. The surgical repair is described and a way to prevent this complication is recommended.

A method for denuding Descemet's membrane by dissection of all overlying stroma, while preserving the corneal endothelial layer, was developed and evaluated. The technique consists in treating the stroma with trypsin and surgically removing the softened stromal layers. With an automated thickness-measuring technique, the endothelium-Descemet preparation was found to range from 23 to 42 micron in thickness. Endothelial cell morphology was normal under specular and light-transmission microscopic examinations. Under electron microscopy, the endothelial cells appeared intact, except for an increase in the number of intracellular vacuoles. Occasionally, small portions of an intercellular space were found to be mildly dilated, but the over-all integrity of the junctional complex was intact. In vitro, the viability of the preparation was comparable with that of a cornea with all layers intact. Endothelial resting membrane potentials, measured with intracellular microelectrodes, were found to be within the normal (33 +/- 2 mV) range. It is thus possible to obtain a viable endothelial layer, completely stripped of stroma.

The viro-static drugs IDU and tromantadin were tested in view of their influence on epithelial regeneration. IDU slows down the speed of epithelisation only slightly, and produces no irreversible damage in the corneal stroma, Descemet's membrane and endothelium of the rabbit eye. Tromantadin, however, slows down the speed of epithelisation quite a lot, even if the dosis is relatively small. We also found substantial changes in corneal stroma and Descemet's membrane, which have been partly recognized histologically as fibrous tissue. Application of these medicaments is recommended only if the relation between side effects and viro-static potency has been carefully rated.