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A Multicenter Study to Map Genes for Fuchs Endothelial Corneal Dystrophy: Baseline Characteristics and Heritability Purpose: To describe the methods for family and case?control recruitment for a multicenter genetic and associated heritability analyses of Fuchs endothelial corneal dystrophy (FECD). Methods: Twenty-nine enrolling sites with 62 trained investigators and coordinators gathered individual and family information, graded the phenotype, and collected blood and/or saliva for genetic analysis on all individuals with and without FECD. The degree of FECD was assessed in a 0 to 6 semiquantitative scale using standardized clinical methods with pathological verification of FECD on at least 1 member of each family. Central corneal thickness was measured by ultrasonic pachymetry. Results: Three hundred twenty-two families with 330 affected sibling pairs with FECD were enrolled and included a total of 650 sibling pairs of all disease grades. Using the entire 7-step FECD grading scale or a dichotomous definition of severe disease, heritability was assessed in families via sib?sib correlations. Both binary indicators of severe disease and semiquantitative measures of disease severity were significantly heritable, with heritability estimates of 30% for severe disease, 37% to 39% for FECD score, and 47% for central corneal thickness. Conclusions: Genetic risk factors have a strong role in the severity of the FECD phenotype and corneal thickness. Genotyping this cohort with high-density genetic markers followed by appropriate statistical analyses should lead to novel loci for disease susceptibility. Cyclosporine A 1% Eye drops for the Treatment of Subepithelial Infiltrates After Adenoviral Keratoconjunctivitis Purpose: To describe the use of cyclosporine A (CSA) 1% eye drops for the treatment of symptomatic corneal subepithelial infiltrates (SEI) occurring as a sequelae of adenoviral keratoconjunctivitis (AK) that are resistant to tapering of corticosteroid eye drops. Methods: This is a retrospective case series of patients seen at 2 institutions who had symptomatic corneal SEI occurring after AK that was resistant to tapering of corticosteroid eye drops and who were subsequently treated with CSA 1%. Information gathered included basic demographic information (age and sex), involved eye(s), duration of symptoms, initial best spectacle-corrected visual acuity (BSCVA), type of corticosteroid used, clinical course, and best spectacle-corrected visual acuity at the last follow-up visit. Results: Twelve eyes of 7 patients had symptomatic SEI develop after AK that were responsive to corticosteroid eye drops but were resistant to tapering. After the initiation of CSA eye drops, the corticosteroid eye drops could be tapered, and all eyes could be maintained on CSA eye drops once per day or less. Mean follow-up time was 13.0 months (range, 4-28 months). Conclusions: CSA eye drops may be an effective corticosteroid-sparing agent for the treatment of SEI after AK. The use of CSA in this setting warrants further study. A Stepwise Approach to Donor Preparation and Insertion Increases Safety and Outcome of Descemet Membrane Endothelial Keratoplasty Purpose: Lamellar techniques for selective replacement of diseased corneal structures have recently been improved. Descemet membrane endothelial keratoplasty (DMEK) allows the sole replacement of the endothelium-Descemet membrane layer (EDM). However, widespread use of DMEK is currently limited because of problems with donor preparation namely the tearing of the Descemet membrane and the difficulty to unfold the EDM graft in the anterior chamber (AC). Methods: A standardized DMEK procedure that allows safe preparation of EDM, atraumatic introduction of EDM into the AC, reliable orientation of EDM during surgery, and stepwise unfolding within the AC is described in 80 patients. Visual acuity and corneal endothelial cell density were assessed. Results: A stepwise approach using a novel bimanual underwater technique to harvest EDM from donor corneal buttons allows reproducible generation of grafts without tearing the Descemet membrane. Injection of the EDM roll into the AC is achieved by use of a standard injector cartridge, whereas the depth of AC is maintained by an irrigation handpiece. Marks at the margin of EDM allow orientation. Finally, unfolding EDM in the AC is achieved by sequential use of water jets and air bubbles. In the early phase of the learning curve, 4 patients were regrafted because of graft failure. Endothelial cell density decreased from 2600 ± 252 to 1526 ± 341 cells per square millimeter 1 month after DMEK. Conclusions: A novel technique for graft preparation and EDM injection results in improved safety with a high rate of successful DMEKs. Pilot, Prospective, Randomized, Double-masked, Placebo-controlled Clinical Trial of an Omega-3 Supplement for Dry Eye: Erratum No abstract available ?PISK-itis? or ?PISK-opathy?? No abstract available Effectiveness of Artificial Tears in the Management of Evaporative Dry Eye Purpose: To compare the efficacies of sodium hyaluronate, hydroxypropyl methylcellulose (HPMC), and a new oil-in-water emulsion (Emustil unidose; SIFI) in the management of lipid-deficient dry eye. Methods: Seventy-five subjects with dry eye were randomly divided into 3 groups. Each was allocated sodium hyaluronate, HPMC, or emulsion eyedrops to be used four times daily for 90 days. Parameters were measured at baseline, 30 days, and 90 days. A compliance visit was performed at days 7 and 60. Results: Significant reduction (P < 0.05) in evaporation and improvement in symptoms in all groups were found. No statistically significant increase in tear turnover rate (TTR) was found with any solution. A significant difference in tear stability and noninvasive tear break-up time (NITBUT) was found in the emulsion and sodium hyaluronate groups but not in the HPMC group (P > 0.05). There was a significant decrease in osmolarity and corneal staining in the emulsion group (P < 0.001) but not in the sodium hyaluronate or HPMC group (P > 0.05). Conclusions: A significant reduction in evaporation and improvement in symptoms in all therapy groups were found from baseline to 90 days. However, no significant effect was seen on TTR for any group. The emulsion drops were shown to perform best, improving tear stability, and decreasing osmolarity and corneal staining. These results are consistent with improvements in the lipid layer of the tear film as a result of prolonged use of emulsion drops. Treatment of Superior Limbic Keratoconjunctivitis With a Large-Diameter Contact Lens and Botulium Toxin A: Erratum No abstract available Outcomes of Repeat Endothelial Keratoplasty in Patients With Failed Deep Lamellar Endothelial Keratoplasty Purpose: To report the outcomes of repeat endothelial keratoplasty (EK) in patients with previous failed deep lamellar endothelial keratoplasty (DLEK). Methods: This retrospective interventional case series involved the review of clinical records of patients with failed DLEK surgery who underwent repeat EK surgery. Results: Ten eyes of 9 patients (2 men and 7 women) were included. The mean age at initial DLEK surgery was 71.2 ± 8.0 years (range, 59?80 years), and the duration to repeat EK was 47 ± 14.3 months (range, 16?63 months). Removal of the failed DLEK donor disc was performed in 7 eyes (70%); in 3 eyes (30%), repeat EK was performed without removal of the failed donor disc. The mean follow-up after repeat EK surgery was 21.7 months (range, 3?44 months). Improvements in corneal clarity and visual acuity were obtained in all eyes. Mean preoperative logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA) was 1.46 (20/577; range, 20/100 to counting fingers) and improved to 0.64 (20/87; range, 20/30 to 20/300) at the final follow-up (P = 0.03). Four eyes had limited BCVA secondary to ocular comorbidites, including age-related macular degeneration, cystoid macular edema, and advanced glaucomatous optic neuropathy. No significant postoperative complications were noted after repeat EK surgeries. Conclusions: Repeat EK in patients with late DLEK failure is effective in improving corneal clarity and is a viable alternative to penetrating keratoplasty (PK). Surgery may be performed with or without removal of the failed donor disc. Visual outcomes may be limited by the existence of ocular comorbidities. Treatment of Fungal Keratitis From Fusarium Infection by Corneal Cross-Linking Purpose: To evaluate the efficacy of corneal cross-linking (CXL) (riboflavin?UV-A) as a simple therapy in Fusarium keratitis. Methods: Twenty-four rabbits were systemically anesthetized, and the stromata of their right corneas were inoculated with Fusarium solani [105 colony-forming units (CFU) per milliliter]. Rabbits were divided into 2 groups: one was treated with CXL 72 hours after infection and the other did not receive any treatment (control). All eyes in both the groups were examined before (days 0 and 3) and after (day 7) CXL treatment. The eyes were enucleated, and corneal buttons were sent for microbiological and histological examinations. Results: All animals developed Fusarium keratitis; there was no statistically significant difference between groups before treatment (day 0, P = 0.397 and day 3, P = 0.702). After CXL treatment, the difference in clinical scores on day 7 between groups was statistically significant (P = 0.00); the CXL group showed significant lower clinical score. The CXL group had 22.45 ± 5.09 CFU/g compared with 42.5 ± 3.12 CFU/g in the control group; this difference was statistically significant (P = 0.01). In the 3 buttons of the control group, similar amounts of Fusarium hyphae and inflammatory cells were observed. In 2 of the 3 buttons analyzed from the CXL group, fewer Fusarium hyphae, inflammatory cells, and nonspecific stromal changes were observed compared with the control group. Conclusions: Treatment of fungal keratitis with CXL seems to be effective in decreasing the intensity and severity of infectious keratitis by F. solani. This therapy may be useful as a coadjuvant in the medical treatment of resistant infections. Descemet Membrane Endothelial Transfer: ?Free-Floating? Donor Descemet Implantation as a Potential Alternative to ?Keratoplasty? Purpose: To describe corneal clearance after reendothelialization of the recipient posterior stroma, by a ?free-floating? donor Descemet roll in the recipient anterior chamber after Descemet membrane endothelial keratoplasty (DMEK), as a potential new approach in managing corneal endothelial disorders. Methods: An 80-year-old woman underwent DMEK for Fuchs endothelial dystrophy. Within hours after the surgery, a ?free-floating? Descemet roll was observed in the recipient anterior chamber. Because the operated eye had low visual potential, the patient requested to await the clinical outcome, which was monitored by biomicroscopy, and endothelial cell density (ECD) and pachymetric measurements were evaluated. Results: Within the first few weeks after DMEK, the transplanted cornea showed diffuse corneal edema with a central pachymetry of more than 1000 ?m. From 1 month onward, the transplanted cornea started to clear in the inferior quadrants. At 6 months, only remnant edema was present in the superior far periphery, pachymetry across the cornea had returned to normal, and ECD measured 830 cells per square millimeter. Conclusions: The performance of a descemetorhexis followed by the implantation of a ?free-floating? Descemet roll in the recipient anterior chamber, tentatively named Descemet membrane endothelial transfer, may have potential as a ?no-keratoplasty? surgical concept in the management of corneal endothelial disorders. Clinical and Histopathologic Features of Failed Descemet Stripping Automated Endothelial Keratoplasty Grafts Purpose: To study the histopathologic features of Descemet stripping automated endothelial keratoplasty (DSAEK) grafts removed after graft failure and to correlate with relevant clinical features. Methods: Retrospective study of 8 cases in 7 patients who experienced DSAEK graft failure during the surgeons' learning phase. Perioperative clinical findings were correlated with pathologic findings of the explanted graft specimens. Imaging software was used to measure the central and peripheral thickness of each graft. Results: Graft failure occurred in association with graft detachment or excessive surgical manipulation. In 4 cases, the donor tissue detached, including 2 cases with routes for bubble escape. In 3 cases, the graft remained attached but failed to clear. The mean preoperative DSAEK button thickness was 205 +/- 61.8 [mu]m. Average death to preservation time was 8 hours 47 minutes, and average preservation to surgery time was 2 days 22 hours. By light microscopy, explanted donor tissue showed varying degrees of keratocyte degeneration and marked endothelial cell loss. Two specimens with bubble escape had less endothelial loss, and 1 specimen showed epithelial ingrowth at the interface. Repeat keratoplasty (5 DSAEK, 2 penetrating keratoplasty) was successful in 6 of 7 cases. Conclusions: This series correlates factors that may play a role in DSAEK failure with histopathologic features of explanted DSAEK lenticules. Marked endothelial loss was common in cases with surgical trauma but was less in cases with bubble escape. One specimen showed an epithelial membrane on the stromal interface. Outcomes of repeat DSAEK in these patients seem promising. (C) 2009 Lippincott Williams & Wilkins, Inc. Therapeutic Efficacy of Topical Epigallocatechin Gallate in Murine Dry Eye Objective: To study the efficacy of topical epigallocatechin gallate (EGCG) for the treatment of dry eye disease (DED). Methods: Seven- to 8-week-old female C57BL/6 mice were housed in the controlled environment chamber to induce DED. Topical 0.01% or 0.1% EGCG, or vehicle, was applied to the eyes of DED mice. Corneal fluorescein staining and the number of corneal CD11b+ cells were assessed in the different groups. Expression of interleukin-1?, tumor necrosis factor-?, chemokine ligand 2, and vascular endothelial growth factor (VEGF)-A/C/D was evaluated by real-time polymerase chain reaction in the corneas at day 9. Corneas were stained for lymphatic vessel endothelial hyaluronan receptor (LYVE)-1 to evaluate lymphangiogenesis, and the terminal transferase dUTP nick end labeling (TUNEL) assay was used to evaluate apoptosis of corneal epithelial cells. Results: Treatment with 0.1% EGCG showed a significant decrease in corneal fluorescein staining compared with the vehicle (24.6%, P = 0.001) and untreated controls (41.9%, P < 0.001). A significant decrease in the number of CD11b+ cells was observed in 0.1% EGCG?treated eyes, compared with the vehicle in the peripheral (23.3%, P = 0.001) and central (26.1%, P = 0.009) corneas. Treatment with 0.1% EGCG was associated with a significant decrease in the corneal expression of interleukin-1? (P = 0.029) and chemokine ligand 2 (P = 0.001) compared with the vehicle and in VEGF-A and VEGF-D levels compared with the untreated group (P = 0.007 and P = 0.048, respectively). EGCG 0.01% also showed a decrease in inflammation at the molecular level but no significant changes in the clinical signs of DED. No cellular toxicity to the corneal epithelium was observed with 0.01% or 0.1% EGCG. Conclusions: Topical EGCG treatment is able to reduce the clinical signs and inflammatory changes in DED by suppressing the inflammatory cytokine expression and infiltration of CD11b+ cells in the cornea. Penetrating Keratoplasty in Active Acanthamoeba Keratitis Purpose: To report the results of penetrating keratoplasty (PK) in active Acanthamoeba keratitis (AK). Methods: Nine patients with deep stromal infiltrates because of AK were treated with intensive antiamoebic medical therapy followed by PK during the acute infectious phase because of poor clinical response or poor compliance. Antiamoebic therapy was tapered after PK. Results: Visual acuity ranged from 20/15 to 20/50 after an average of 17 months after PK with no signs of recurrences. Patients had rapid resolution of symptoms. Conclusion: PK is a viable option for active AK not responding to maximum medical treatment. (C) 2010 Lippincott Williams & Wilkins, Inc. Small-Incision Descemet Stripping Automated Endothelial Keratoplasty: A Comparison of Small-Incision Tissue Injector and Forceps Techniques Purpose: To describe a novel, small-incision, no-fold Descemet stripping automated endothelial keratoplasty (DSAEK) graft injector and to compare complications, visual acuity, and endothelial cell loss with a forceps technique. Methods: An Institutional Review Board?approved, interventional, nonrandomized, consecutive case series analysis of 175 eyes undergoing DSAEK for Fuchs dystrophy and bullous keratopathy. The injector arm is prospective, and the forceps arm is retrospective. Seventy grafts were performed with a DSAEK graft injector, and 105 grafts were performed using a small-incision forceps technique. Preoperative and postoperative visual acuities at 3 and 6 months, 6-month endothelial cell counts, and complications, including graft dislocation, failure, and rejection, were recorded. Fifty-seven of 232 eyes met exclusion criteria for previous incisional corneal or glaucoma surgery. Results: There were 4 eyes (5.7%) in the injector group and 29 eyes (27.6%) in the forceps group that required a re-bubble procedure because of graft detachment. One graft (1.4%) failed in the injector group and 7 grafts (6.5%) failed in the forceps group. Excluding eyes with other ocular comorbidities (43), in the injector group 74% were 20/40 or better at 6 months and 100% were 20/60 or better. In the forceps group, 72% were 20/40 or better at 6 months and 98% were 20/60 or better. Six-month postoperative endothelial cell counts were available for 84 (46 injector and 38 forceps) eyes, with an average cell loss of 28.3% in the injector group and 44.1% in the forceps group. Conclusions: DSAEK is an effective treatment of endothelial dysfunction. Surgical technique is important to limit endothelial cell loss and prevent complications, such as graft dislocation. The injector device has several advantages over the trifold forceps technique, including decreased endothelial cell loss, graft dislocation rate, and graft failure rate, and it reduces the DSAEK learning curve. DSAEK graft injectors likely will have a role in the future of endothelial keratoplasty. Indications for Penetrating Keratoplasty in North China Purpose: To analyze leading indications for penetrating keratoplasty (PKP) in north China and changing trends in them. Methods: We retrospectively reviewed the records of patients who underwent PKP at Shandong Eye Institute from January 1997 to December 2002. Infectious keratitis (fungal, bacterial, and acanthamoeba), herpes simplex keratitis (HSK), corneal scarring, keratoconus, bullous keratopathy, regrafting, corneal dystrophy and degeneration, and others were included in the indications for PKP. Initial diagnoses and causes of regrafting were recorded, as well as the related intraocular surgeries for bullous keratopathy. Results: A total of 1702 patients (1702 eyes) were included in this study. The leading indications for PKP were infectious keratitis (31%), followed by HSK (18%), corneal scarring (16%), keratoconus (13%), bullous keratopathy (7%), regrafting (5%), and corneal dystrophy and degeneration (4%). Percentage of PKP for keratoconus and bullous keratopathy increased significantly during the 6 years, contrary to HSK and corneal scarring. Fungal infections accounted for 66% of infectious keratitis. Of 118 bullous keratopathy cases, 90 (76%) were associated with cataract surgery. The leading initial diagnoses of regrafting were corneal burns (25%), HSK (23%), and infectious keratitis (14%); the major causes included immune rejection (61%), graft infection (14%), and recurrence of HSK (10%). Conclusions: Infectious keratitis remains the most common indication for PKP in north China. Moreover, there is an increasing trend in the percentage of PKP for keratoconus and bullous keratopathy. (C) 2007 Lippincott Williams & Wilkins, Inc. Effects of a New Lipid Tear Substitute in a Mouse Model of Dry Eye Purpose: The present investigation is aimed to evaluate the effect of a new lipid artificial tear on tear volume and ocular surface signs in a mouse model of dry eye and to test the hypothesis that the combined application with sodium hyaluronate can improve the performance of the treatments. Methods: A new oil-in-water emulsion, a 0.2% sodium hyaluronate solution, or their combined administration were given to dry eye mice maintained in a controlled environment chamber and treated with scopolamine (0.75-mg transdermal patch). Mice were treated 4 times a day with ( ) sodium hyaluronate, ( ) emulsion, and ( ) sodium hyaluronate followed by emulsion. A control group of mice exposed to controlled environment chamber remained untreated (CTRL+). Tear volume and corneal damage were assessed after 3 and 7 days of treatment by cotton thread test and fluorescein staining. Results: As regards tear volume, sodium hyaluronate did not show a statistically significant effect at either end point; the emulsion was effective after 7 days, whereas their combined administration counteracted the lacrimal decrease induced by the model both at 3 and 7 days. Corneal damage was reduced in all treated groups with respect to CTRL+. This effect was statistically significant after 3 days when the emulsion alone or in combination with sodium hyaluronate was used, while hyaluronate improved this clinical sign after 7 days. Conclusions: Our data suggest that the new lipid tear substitute can be used to treat clinical signs of dry eye and that the combined administration with hyaluronate can decrease the lag time before the effect, when the evaporative and the aqueous-deficient components are present. KeraRing Intrastromal Corneal Ring Segments for Correction of Keratoconus Purpose: Intrastromal corneal ring segments (ICRSs) are small arc-like implants that are being used increasingly as a minimally invasive treatment for patients with keratoconus. This study assessed the effectiveness of KeraRing implants, a type of ICRS, to treat keratoconus. Methods: Retrospective case series descriptive study of 43 patients (55 eyes) with keratoconus who underwent KeraRing implantation from February 2008 to June 2009. Patients who had intraoperative or postoperative complications and/or did not complete at least 6 months of follow-up were excluded. All patients underwent complete ophthalmologic examinations that included measurement of the uncorrected visual acuity (UCVA), best spectacle?corrected visual acuity (BSCVA), manifest refraction, and keratometry before and 2 days, 2 weeks, 1 month, and 3 and 6 months after surgery. The ring segments were chosen based on a nomogram from the manufacturer. Results: Six months postoperatively, the mean UCVA increased significantly (P < 0.05) from 0.10 ± 0.11 to 0.32 ± 0.25 and the mean BSCVA increased from 0.36 ± 0.23 to 0.57 ± 0.24 (P < 0.05). The mean spherical refractive error significantly (P < 0.05) improved from ?4.85 ± 2.90 diopters (D) to ?1.89 ± 2.68 D, and the mean cylindrical refractive error significantly (P < 0.05) improved from ?3.65 ± 1.70 D to ?2.60 ± 1.62 D. The mean spherical equivalent significantly (P < 0.05) decreased from ?6.68 ± 2.93 D to ?3.19 ± 2.75 D, and the mean keratometry value decreased from 51.83 ± 4.14 D to 47.27 ± 3.68 D. The improvement in the UCVA and BSCVA continued over the 6-month postoperative period, but significant changes occurred only during the first 3 months. These changes occurred in patients with all grades of keratoconus. Conclusions: KeraRing implantation provided significant improvement in visual acuity, spherical equivalent, and keratometry results. This ICRS is an effective treatment for managing keratoconus and might delay or even avoid the need for penetrating keratoplasty. In Vivo Biomechanical Changes After Corneal Collagen Cross-linking for Keratoconus and Corneal Ectasia: 1-Year Analysis of a Randomized, Controlled, Clinical Trial Purpose: To investigate the in vivo, corneal, biomechanical changes after corneal collagen cross-linking (CXL) using the Ocular Response Analyzer (ORA) in patients with keratoconus and post-laser in situ keratomileusis (LASIK) ectasia. Methods: Single-center, prospective, randomized, controlled, clinical trial. After CXL (69 eyes, 46 keratoconus and 23 post-LASIK), corneal hysteresis (CH) and corneal resistance factor (CRF) were measured using the ORA and analyzed in a treatment, sham control, and fellow eye control group at baseline and 1, 3, 6, and 12 months. Results: There were no significant changes in CH (change = 0.05 ± 1.5; P = 0.78) or CRF (change = 0.29 ± 1.4; P = 0.1) at 1 year compared with preoperative values. Changes in CH and CRF were not correlated with changes in clinical outcomes of uncorrected visual acuity, best spectacle-corrected visual acuity, and maximum keratometry. There were no significant changes in CH in the sham or fellow eye control groups (Psham = 0.7; PFE = 0.3) or CRF (Psham = 0.6; PFE = 0.72). Conclusions: Despite an increase in CRF at one month, there were no statistically significant changes in CH and CRF measurements 1 year after CXL. Development of other in vivo biomechanical metrics would aid in evaluating the corneal response to CXL. Noninvasive, Objective, Multimodal Tear Dynamics Evaluation of 5 Over-the-Counter Tear Drops in a Randomized Controlled Trial Purpose: To assess the ability of a noninvasive, objective, multimodal system to compare the efficacy and optical quality of 4 different groups of 5 over-the-counter tear drops. Methods: Wavefront sensing and optical coherence tomography (OCT) were used to objectively assess visual quality and tear volume, respectively, after the over-the-counter tear drops [2 polyethylene glycol (PEG)-400, 1 carboxymethyl cellulose (CMC), 1 polyvinyl alcohol/PEG-400 (PVA), and 1 glycerine/polysorbate-80] were administered to 23 patients with aqueous-deficient dry eye in a randomized, controlled, double-masked trial. Measurements at each of the 5 visits were taken from both eyes at baseline and 5, 20, and 40 minutes after drop instillation. Results: At 5 minutes after drop instillation, the 2 PEG drops showed significant worsening of visual quality (?128.87%, P = 0.001) compared with CMC, PVA, and glycerine drops. Tear volume was elevated significantly with PEG and CMC drops at 5 minutes (+33.2%, P = 0.002; +29.9%, P < 0.001) compared with the other groups. Subjects with a Schirmer score of less than 5 mm at 5 minutes showed improvement in visual quality with PEG drops, whereas those with a fluorescein staining score of 1 to 2 showed improvement with both PEG and CMC drops. A trend toward decreasing visual quality with increasing tear meniscus was noted. Conclusions: Noninvasive multimodal imaging has the potential to evaluate tear dynamics and the efficacy of artificial tears objectively. Certain artificial tear components and the temporary increase in tear volume after instillation of artificial tears may contribute to transient reduction of visual quality. Confocal Microscopic Observations of Stromal Keratocytes in Soft and Rigid Contact Lens Wearers Purpose: To determine the density of corneal stromal cells in wearers of soft contact lenses (SCLs) and rigid gas-permeable (RGP) contact lenses (CLs). Methods: The keratocyte density (KD) was measured at different depths of the stroma by confocal microscopy. In study 1, 32 wearers of rigid gas-permeable (RGP) lenses and 30 wearers of SCLs were studied. Forty volunteers with no history of CL wear were studied as controls. In study 2, 16 volunteers with no history of CL wear were divided into 2 groups; 7 subjects wore RGP lenses (oxygen transmissibility, Dk/L, 35) and 9 subjects wore SCLs (Dk/L, 34). All subjects were asked to wear the CLs daily for 6 months. Results: In study 1, the KDs in the anterior stroma (AST) and the posterior stroma (PST) of the cornea were significantly lower in the RGP lens group than in the control group. The KD in the SCL group was significantly lower at all depths of the cornea than that of the control group. In study 2, the KD in the AST of the RGP lens group was significantly lower after 1 month of CL wear. The KD in the AST and PST of the SCL group was decreased significantly at 1 month, and all layers were decreased by 10% to 20% 6 months after wearing CLs. At 5 weeks after discontinuation of SCL wear, the KD in all layers was not significantly different from that at the baseline. Conclusions: The change in the KD was greater in CL wearers than in volunteers with no history of CL wear and also greater in SCL wearers than in RGP lens wearers. Analysis of the KD by confocal microscopy may be a useful method for evaluating the effect of CL wear.

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