Epidemiology and Outcome of Microbial Keratitis: Private University Versus Urban Public Hospital Care.

PURPOSE: To review the epidemiology, risk factors, microbiologic spectrum, and treatment of microbial keratitis during a 5-year period at an urban public hospital in comparison with an adjacent private university practice. METHODS: Retrospective chart review in the 5-year interval, 2009 through 2014. Primary outcome measures included patient age at presentation, best-corrected visual acuity (BCVA), risk factors, culture and sensitivities, treatment, and complication occurrence. RESULTS: A total of 528 eyes with microbial keratitis were identified, 318 in the public cohort and 210 in the private cohort. Contact lens wear was the most common risk factor in the public cohort, whereas ocular surface disease was the most common risk factor in the private cohort. Gram-positive organisms represented 47.3%, gram-negative organisms 32.1%, fungal organisms 13.6%, and Acanthamoeba 6.4% of corneal isolates. Gentamicin resistance was 4.4% and tobramycin resistance was 2.9%. The inpatient treatment rate of the public cohort was 40% compared with 4% in the private cohort. In the public cohort, average BCVA at resolution was 20/82 (log of minimal angle of resolution [logMAR] 0.61). For the private cohort, average BCVA at resolution was 20/73 [logMAR, 0.56]. The perforation rate was 8% in the public cohort compared with 4% in the private cohort. Six percent of cases underwent urgent penetrating keratoplasty in the public cohort versus 2% in the private cohort. CONCLUSIONS: Microbial keratitis remains a clinical challenge in the urban public hospital setting. The risk profile of patients presenting in the public hospital setting may be different from patients presenting in a private care setting. Public hospital patients may present later in the course of their infection and thus have a higher rate of complications regardless of effective antimicrobial therapy.

Corneal Pseudodendritic Lesions Masquerading as Herpetic Keratitis in a Patient With Tyrosinemia Type I.

OBJECTIVE: To describe the clinical findings of a patient with tyrosinemia type I with noncompliance to a protein-restricted diet, treated with 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC). METHODS: Clinical findings at the initial examination and after strict compliance to a protein-restricted diet after 4 weeks follow-up are described in a patient with tyrosinemia type I on NTBC treatment, who had been treated with presumed herpetic keratitis. RESULTS: A 10-year-old girl diagnosed with hereditary tyrosinemia type I and on NTBC treatment presented with photophobia and ocular discomfort in both eyes. An ophthalmologic examination demonstrated bilateral dendritiform epithelial lesions in the central cornea, staining faintly with fluorescein. These lesions were subsequently intermittently treated with topical antivirals for presumed herpes simplex virus keratitis and lubricant eye drops for 9 months without resolution; however, when strict compliance with a protein-restricted diet was instituted, nearly a complete resolution of the lesions was noted at the 4-week follow-up. CONCLUSIONS: Although type II tyrosinemia is known to have corneal involvement, the natural course of tyrosinemia type I has not been shown to have corneal involvement. Corneal involvement in type I tyrosinemia may be an indicator of dietary noncompliance and may show complete resolution with a strict compliance to protein-restricted diet only.

Improvement of Subjective Symptoms and Eye Complications When Changing From 2-Week Frequent Replacement to Daily Disposable Contact Lenses in a Subscriber Membership System.

PURPOSE: Subjective symptoms and other eye complications were assessed and retrospectively compared in patients belonging to a proprietary membership system who switched from 2-week frequent replacement (2WFR) wear to daily disposable (DD) lens use. METHODS: Questionnaire responses were completed by all patients for a 5-year interval between October 2008 and September 2013 from 83 wearers in three Japanese clinics (59 female and 24 male; average age: 33.4±10.9 years). Complications were recorded for each patient at times of reexamination. RESULTS: Over the 5-year observation period, the 83 patients wore lenses for more than 26 months. The average duration of use of 2WFR lenses was 14.5±2.7 days/lens (n=83) and subsequently 1.03±0.12 days/lens (n=83) for DD lenses. Compliance with the duration of use was consistently good as monitored by requests for lens resupply in both wearing modalities. The subjective complaint of dryness tended to consistently show improvement by the change to DD wear: 18.1% vs. 30.1% (P=0.10, Fisher exact test). Among eye complications noted in each group, the occurrence of superficial punctate keratitis (SPK) was significantly decreased in DD wear: 9.6% vs. 26.5% (P=0.008, Fisher exact test). The main reasons given by patients for changing to DD wear were (1) "DD lens wear was more hygienic" (78.6%) and (2) "DD lens use is more convenient for travel/business trips" (64.3%). Comments after the switch in wear were (1) "easy and convenient" (95.7%) and (2) "I don't have to worry about expiration dates" on solutions (57.1%). Overall, 95.7% of wearers making the change answered as "satisfied" and "mostly satisfied." CONCLUSIONS: In the subscription membership program, which provided free lens replacement and/or reexamination, individual compliance with duration of wear in 2WFR wear cycles was good; however, these patients switching to DD wear tended to have improvement in their subjective complaints of dryness and objectively demonstrated a significant reduction of SPK at follow-up examinations.

Impact of Donor Age on Corneal Endothelium-Descemet Membrane Layer Scroll Formation.

OBJECTIVE: To correlate corneal endothelium-Descemet membrane (EDM) layer parameters of scroll tightness with donor age, endothelial cell density (ECD), and history of diabetes. METHODS: Endothelium-Descemet membrane layer scrolls were harvested from 26 corneoscleral buttons using the SCUBA technique by a cornea-fellowship trained ophthalmologist masked to donor age. Two independent outcome parameters were used to characterize the scrolling severity of successfully harvested tissue: scroll width and tendency for EDM scroll formation (referred to as scroll rating on a 1-4 scale: incomplete scroll formation to tightly scrolled). RESULTS: Mean donor age was 59 ± 17 (15-69) years. Mean ECD of EDM scroll was 2,451 ± 626 (range: 1,307-3,195) cells per square millimeter. Using stepwise linear regression, a significant correlation was found between scroll width and donor age (R=0.497, P<0.05). Additionally, a significant inverse correlation was found between scroll width and ECD (R=-0.605, P<0.05). There was no statistically significant correlation between a donor history of diabetes and the parameters of scrolling tendency. CONCLUSIONS: Our data suggest that using older donors reduces EDM scroll tightness.

Compliance study of contact lens wearers in Japan--part 2: evaluation of a subscribed membership system.

OBJECTIVE: To examine the hypothesis that membership in a contact lens (CL) supply system is associated with better compliance for regular wearers (members) who belong to the subscription membership system. METHODS: Subjects were 104 members and 100 nonmember wearers of 2-week frequent replacement silicone hydrogel CLs whose clinical information was retrospectively available for 1.5 to 2 years in the interval between September 2010 and August 2012. The average duration of use of a single lens was calculated from the number of lenses supplied during the observation period and surveyed using questionnaires. Subjective symptoms and eye complications were also documented and compared. RESULTS: The average duration of use of a lens was significantly longer in nonmembers (17.8±5.6 days/lens; n=91) than in members (14.2±3.5 days/lens; n=98) (P<0.001, Mann-Whitney U test). The number of wearers who replaced their lenses within 15.4 days per lens wear was significantly higher in members (74.5%) as compared with nonmembers (45.1%) (P<0.001, Fisher exact test). Levels of compliance reported by wearers did not match with those indicated in clinical records. In recorded eye complications, the rate of incidence of allergic and giant papillary conjunctivitis tended to be higher in nonmembers as compared with members. CONCLUSIONS: The hypothesis that a membership system could be associated with better compliance was found to be supported by clinical records. It is suggested that a membership system is useful for identifying wearers who want to be more compliant and that better compliance may reduce long-term complications of lens wear.

Compliance study of contact lens wearers in Japan, part 1: internet survey of actual circumstances of lens use.

PURPOSE: To conduct a survey of contact lens (CL) wearers who use their CLs with satisfaction in Japan and to establish the actual circumstances of CL use. METHOD: An Internet survey was conducted in 1,000 CL wearers in Japan with questionnaires concerning CL purchase/change, compliance with the duration of wear, and occurrence of complications of CL use. RESULTS: Replies from 636 women (63.6%) and 364 men (36.4%) were received. The largest source of CL purchase was CL specialty stores (eyeglass chains, 41.3%). The most frequent CL types were 2-week frequent replacement (2WFR) soft CLs (SCLs) (32.1%), daily disposable (DD) (31.0%), and other lenses. The main determining factors of purchase were "price" (38.0%), "recommendation of a doctor/staff" (37.6%), and "comfort" (34.1%). The number of wearers who changed their CLs was 372 (37.2%), and the main reasons for change were "inexpensive" (34.9%) and "recommendation of a doctor/staff" (31.2%). In DD and 2WFR/planed replacement SCLs, 270 (42.7%) of 632 wearers were compliant with the recommended duration of use, and the remainder were self-identified as noncompliant. The main reason given for noncompliant behavior was "no harm in extending the duration of use" (60.3%). The number of wearers with eye complications related to lens was 373 (37.3%). CONCLUSIONS: The choice of CLs by wearers seems to be price driven rather than being safety focused. Despite being aware of noncompliant behaviors regarding CL use, there were many noncompliant wearers. Clearly, ophthalmologists, optometrists, CL manufacturers, and other CL-related practitioners should cooperate and better educate patients to promote the importance of compliance with safe lens use.

Comparison of hepatitis B, core, HBc, and hepatitis B antibody, anti HBs, in a presumed low risk donor population.

Donors screened by medical social history interview negative for high risk behavior or communicable disease history, but subsequently exhibiting reactive serological markers, emphasize importance of duel safe guarding factors for determining donor suitability. This report examines a relationship between two immunoabsorption assay tests, hepatitis B core (HBc) antibody, a required food and drug administration (FDA) test, and hepatitis B antibody (anti HBs), non-required test. Reactive serology results, 129 cases, 3,581 donors (2008-2012) for HBc as the only initially positive serological marker were subjected to anti HBs testing in this history pre-screened donor population. Enzyme linked immunoabsorption assay kits hepatitis B, core and antibody, were used in this study. All samples were initially tested for human immunodeficiency virus, hepatitis B, and hepatitis C, utilizing nucleic acid testing and antigen antibody immunoabsorption assay. Testing was performed by a FDA-registered CLEA-certified reference laboratory. Samples were deceased donor blood samples and a limited number of pre-mortem samples, separated, stored and analyzed according to manufacturer recommendation and FDA regulations. 129 reactive HBc only samples, were subsequently tested for anti HBs. Of these 129, 94 were found to be reactive for anti HBs. This represented 72 % of samples tested for antibody, a higher percentage than anticipated for a medical history negative, low risk population.

Effects of multipurpose solutions on the viability and encystment of acanthamoeba determined by flow cytometry.

PURPOSE: To evaluate simultaneously the effects of multipurpose contact lens care solution (MPS) on the viability and encystment of Acanthamoeba using flow cytometry. METHODS: Viability and encystment rate were evaluated using Acanthamoeba castellanii (ATCC 50514 and ATCC 50370) and three clinical strains of Acanthamoeba spp. isolated from patients with Acanthamoeba keratitis. Acanthamoeba trophozoites (1.0 × 10(5) cells/mL) were exposed to four kinds of commercially available MPSs for 24 hours. After dispensing the cell suspension into two portions, one portion was stained with 0.004% Congo Red (CR), a fluorescence dye to stain the inner cell wall of cysts, and the other portion was stained with a mixture of Congo Red and 3% sarkosyl (CRS), a detergent to lyse the trophozoites and pseudocysts. Flow cytometric analysis of the treated portions was then carried out on an EPICS ALTRA flow cytometer. The encystment rate and disinfecting efficacies (percentage of rounded trophozoites, "pseudocyst") were calculated by the rates of CR-stained, CR-nonstained, and CRS-stained populations, respectively. Ultrastructural features of resistant (mature or immature) cysts and pseudocysts were observed by transmission electron microscopy. RESULTS: Resistant cysts and rounded trophozoites (pseudocysts) were stained with CR, whereas native (unrounded) trophozoites were not. Resistant cysts were also stained with CRS unlike pseudocysts. Three clinical isolates showed higher resistance and higher encystment rates than two ATCC strains when treated with encystment-positive control solution. Disinfecting efficacy of each MPS was not directly related to each encystment rate. Transmission electron microscopy observations showed basic differences in the ultrastructure of pseudocysts produced by MPSs and resistant cysts. CONCLUSIONS: These results suggest that viability and encystment of Acanthamoeba are independent phenomena, and therefore disinfecting efficacy of MPS and encystment rates of Acanthamoeba should be evaluated, respectively. Thus, it is important to evaluate simultaneously the disinfecting efficacies and encystment rates of newly developed premarket MPS using the authors' novel flow cytometric methods.

Evaluation of diminished microbial contamination in handling of a novel daily disposable flat pack contact lens.

PURPOSE: To evaluate the efficacy of a novel daily disposable (DD) flat package in regard to microbial contamination on the anterior and posterior surfaces of a contact lens (CL) during handling of the lens for insertion. METHODS: Four kinds of commercially available general blister-packed daily disposable contact lenses (DD CLs) as controls and a novel Magic 1-day Menicon Flat Pack as a test lens were used for this in vitro study. Lenses were removed from their packages using fingers coated with fluorescein 3 to 5 µm beads or an approximately 7×10(2) to 2×10(3) colony-forming unit (CFU)/mL Staphylococcus aureus suspension. The transfer of fluorescein beads to the surface of the lenses was then observed by fluorescence microscopy. Microbial contamination on the lenses was observed by light microscopy after a 2-day incubation period; and, the number of colonies isolated from the contaminated lenses was determined after 4 days of incubation. RESULTS: The number of fluorescein beads on the Magic lens was significantly less (p<0.05) than that of the general blister-packed control lenses. Adherence of microbial colonies was observed on both inner and outer surfaces of general blister-packed lenses, whereas no colony formation was found on the inner surface of the Magic lens, and the lowest bacterial adherence was observed for the Magic lens. CONCLUSIONS: The data demonstrated that placement of the Magic DD lens onto the eye is accompanied by diminished microbial contamination compared with general blister-packed DD CLs. Eye care professionals; however, should instruct patients to comply with intended use of DD CLs to prevent CL-associated microbial keratitis. In all cases, hand washing is mandated prelens insertion.

Contact lens care solutions downregulate membrane-associated mucins 1 and 16 in cultured human corneal epithelial cells and at the rat corneal surface in vivo.

OBJECTIVE: The purpose of this study was first to evaluate the effect of multipurpose contact lens care solutions (MPSs) on the expression of membrane-associated mucins (MUC1 and MUC16) in SV40-transformed human corneal epithelial (HCE-T) cells and in vivo rat cornea. The second aim of this study was to determine the role of the common MPS additive boric acid in reducing mucin expression and release. METHODS: The HCE-T cells were exposed to different concentrations of MPS-F, MPS-G, MPS-H, MPS-I, and MPS-J with 100% treatment for 30 minutes and 10% treatment for 24 hours. MUC1 and MUC16 expressions were subsequently analyzed by Western blotting. Wister rats were also subjected to MPS-A, MPS-B, MPS-C, MPS-D, and MPS-E and received phosphate-buffered saline exposure (1 drop in the right eye every 10 minutes for 1 hour). The left eye was used as control. Cornea sections and lysates were used for the immunohistochemical assay of MUC1 and MUC16 expressions. Conditioned media from treated HCE-T cells were also analyzed using Western blotting. RESULTS: The MPSs containing boric acid downregulated MUC1 and MUC16 in the rat cornea, whereas MPSs without boric acid had no effect as demonstrated by the Western blotting and immunohistochemical analysis. Conditioned media from MPS-containing boric acid revealed some trace of MUC16. CONCLUSIONS: The clinical use of MPSs containing boric acid that reduce MUC1 and MUC16 availability should be avoided. Additionally, the presence of MUC16 in the conditioned media suggests that boric acid may have enhanced cleavage of MUC16 at the cell membrane surface.

The accuracy of the double-K adjustment for third-generation intraocular lens calculation formulas in previous keratorefractive surgery eyes.

PURPOSE: To evaluate the effect of the double-K (DK) modification on third-generation formulas. METHODS: Thirty-eight previously myopic and 24 previously hyperopic eyes that underwent phacoemulsification with intraocular lens (IOL) insertion after Laser in situ keratomileusis (LASIK) were evaluated. Pre-LASIK refraction and keratometry, post-LASIK topography, axial length (AL), IOL type and power, and 1-month postphacoemulsification refraction were recorded spherical equivalent after phacoemulsification (SE(postphaco)). Measured corneal power was adjusted using published and validated methods for postmyopic and posthyperopic LASIK. For each eye, and using SE(postphaco), different DK-IOL formulas were used to calculate the corresponding IOL power, the outcome measure, which was compared with the implanted IOL. RESULTS: DK-Holladay 1 yielded the highest Pearson correlation coefficient (PCC), 0.955 for myopes and 0.943 for high myopes (AL>26 mm). Mean error (ME) and mean absolute error (MAE) for myopes for DK Sanders-Retzlaff-Kraff theoretical formula [DK-SRK/T] were 0.44±0.84 D and 0.75±0.61 D for DK-SRK/T compared with -0.04±0.67 D and 0.52±0.40 D for DK-Holladay 1 (P<0.001 and P=0.016, respectively), and 0.03±0.88 and 0.64±0.58 for DK-Hoffer Q. For high myopes, ME and MAE were 0.75±0.81 D and 0.84±0.69 D for DK-SRK/T, and -0.05±0.74 D (P<0.0001) and 0.57±0.45 D (P=0.019) for DK-Holladay 1. About 29% of DK-SRK/T eyes with large AL had MAE>1.5 D, compared with 0% for DK-Holladay 1 and 14% for DK-Hoffer-Q. Eyes with previous hyperopic LASIK faired similarly for all formulas, with similar PCCs, and only 8% in each category with MAE>1.5 D. CONCLUSIONS: DK-SRK/T overestimates IOL power in eyes with large AL, especially with concomitant steep pre-lasik keratometry. Among third-generation formulas, DK-Holladay 1 seems more accurate to use in postmyopic LASIK eyes.

Elevated IGFBP3 levels in diabetic tears: a negative regulator of IGF-1 signaling in the corneal epithelium.

To determine the ratio of IGFBP3:IGF-1 in normal and diabetic human tears, and in telomerase-immortalized human corneal epithelial cells (hTCEpi) cultured under elevated glucose conditions and to correlate these changes with total and phosphorylated levels of IGF-1R. Tear samples were collected noninvasively from diabetic subjects and non-diabetic controls; corneal sensitivity was assessed using a Cochet-Bonnet Aesthesiometer. Conditioned media were collected following culture of hTCEpi cells in normal (5 mM) and elevated (25 mM) glucose conditions; mannitol was used as an osmotic control. IGFBP3, IGF-1, and phosphorylated IGF-1R levels were assessed by ELISA. IGFBP3 and IGF-1R mRNA were assessed by real-time polymerase chain reaction (PCR). Total and phosphorylated IGF-1R expression in whole cell lysates was assessed by western blot. There was a 2.8-fold increase in IGFBP3 in diabetic tears compared to non-diabetic controls (P=0.006); IGF-1 levels were not significantly altered. No difference in corneal sensitivity was detected between groups. The concentration of IGFBP3 in tears was independent of IGF-1. Consistent with human tear measurements in vivo, IGFBP3 secretion was increased 2.2 fold (P<0.001) following culture of hTCEpi cells under elevated glucose conditions in vitro. Treatment with glucose and the mannitol control reduced IGFBP3 mRNA (P<0.001). Total IGF-1R levels were unchanged. The increase in the IGFBP3:IGF-1 ratio detected in diabetic tears compared to normal controls blocked phosphorylation of the IGF-1R by IGF-1 (P<0.001) when tested in vitro. Taken together, these in vivo and confirmatory in vitro findings suggest that the observed increase in IGFBP3 found in human tears may attenuate IGF-1R signaling in the diabetic cornea. A long-term increase in IGFBP3 may contribute to epithelial compromise and the pathogenesis of ocular surface complications reported in diabetes.

The impact of cellular debris on Pseudomonas aeruginosa adherence to silicone hydrogel contact lenses and contact lens storage cases.

OBJECTIVES: To evaluate neutrophil-enhanced Pseudomonas aeruginosa (PA) biofilm formation on silicone hydrogel contact lenses and to determine the effect of epithelial biodebris on PA adherence in contact lens storage cases. METHODS: A fully invasive PA corneal isolate stably conjugated to green fluorescent protein was used. Unworn lotrafilcon A contact lenses were incubated at various ratios of PA to polymorphonuclear neutrophil (PMN) for 24 hours at 37°C. Lens-associated PA was evaluated using laser scanning confocal microscopy and nonviable PA were visualized using propidium iodide. Viable bacteria were enumerated by colony-forming unit (CFU) analysis. For acute epithelial cell studies, PA viability was determined after coincubation with freeze-thaw epithelial cell lysates in 96-well polystyrene plates. Levels of residual cellular debris and bacterial viability were further assessed in used contact lens storage cases. RESULTS: Laser scanning confocal microscopy demonstrated that cotreatment with PMA-stimulated neutrophils increased PA adherence over 24 hours to lens surfaces with a striking alteration of PA architecture. Propidium iodide staining showed that the adherent bacteria consisted of a mixture of viable and nonviable PA; a PMN-associated increase in viable PA was confirmed by CFU (PA:PMN 0.1:1, P = 0.025; PA:PMN 1:1, P = 0.005). Acute epithelial cell debris studies revealed a significant increase in viable PA in 96-well plates in the presence of epithelial freeze-thaw lysates (PA:debris 1:1, P = 0.002; PA:debris 100:1, P = 0.002). Crystal violet staining of used lens storage cases revealed residual cellular debris at all time points, which was independent of microbial contamination; all lens cases used for periods of 9 months or more were uniformly associated with high levels of viable microorganisms. CONCLUSION: These results demonstrate that prolonged corneal inflammation with the presence of PMNs when confronted with simultaneous PA challenge in extended contact lens wear has the potential to stimulate biofilm formation on silicone hydrogel contact lenses. These findings further suggest that a persistent buildup of extracellular debris in lens storage cases may contribute to the heavy biofilms reported on these surfaces.

Hypoxia-induced downregulation of ΔNp63α in the corneal epithelium.

PURPOSE: The aim of this study was to establish a relationship between hypoxic stress and the expression of ΔNp63α in an established rabbit contact lens model and in cultured corneal epithelial cells. METHODS: New Zealand white rabbits were fit in one eye with either a non-oxygen transmissible or hyper-oxygen-permeable rigid contact lens for 24 hrs of wear; the contralateral eye was used as a control. All the rabbits underwent a bilateral nictitating membranectomy to facilitate lens retention. ΔNp63α expression was analyzed by immunofluorescence and western blot. Telomerase-immortalized human corneal epithelial cells (hTCEpi) were grown in serum-free media and treated with the hypoxia-mimetic cobalt chloride to simulate hypoxia for 6 hrs (short term) or 24 hrs (prolonged). Transcriptional activity and protein levels were assessed using luciferase reporter assays, reverse transcription polymerase chain reaction, and western blot. Cell viability was assessed by live/dead assay. RESULTS: Compared with the non-lens wearing eye, 24 hrs of non-oxygen transmissible lens wear in vivo decreased ΔNp63α protein levels in both the limbal and central corneal epithelium; this decrease was not found in the hyper-oxygen transmissible lens group. In hTCEpi cells in vitro, hypoxia increased the activity of the ΔN promoter but reduced the levels of ΔNp63α mRNA after 24 hrs of prolonged culture. Similarly, ΔNp63α expression levels were unaffected from short-term exposure but decreased after 24 hrs. Live/dead assay confirmed the presence of viable cells after CoCl2 treatment at 6- and 24-hr time points. Cells treated for 24 hrs were viable but were smaller and rounded with signs of membrane blebbing, consistent with early stages of apoptosis. CONCLUSIONS: Hypoxic stress induced by either prolonged wear of a nonoxygen transmissible lens in vivo or hypoxic-mimic conditions by cobalt chloride in vitro downregulates ΔNp63α in the corneal epithelium. The loss of ΔNp63α in response to hypoxic stress may contribute to the disruption of normal renewal mechanisms reported with low oxygen transmissible contact lens wear and prolonged eyelid closure.

Corneal endothelial characteristics and central corneal thickness in a population of Turkish cataract patients.

OBJECTIVES: The aim was to assess corneal endothelial characteristics and central corneal thickness (CCT) in a population of Turkish cataract patients and to define the impact of age and gender on these parameters. METHODS: Five hundred and seventeen cataract patients were examined with noncontact specular microscope preoperatively. The eye planned to be operated was selected for analysis. The parameters measured were endothelial cell density (ECD), cell area (CA), coefficient of variation (CV) of the CA, percentage of hexagonal cells (PHCs), and CCT. RESULTS: The mean values in ECD, CA, CV, PHC, and CCT in all eyes were 2,258 ± 474 cells per square millimeter, 468 ± 130 µm(2), 39%±7%, 49%±12%, and 500 ± 37 µm, respectively. Regression analysis revealed a statistically significant decrease in ECD (R=-0.169, P<0.0001), increase in CA (R=0.186, P<0.0001), and decrease in the CCT (R=-0.122, P=0.006) with increase in age. The changes in the CV (R=0.008, P=0.861) and PHC (R=-0,060, P=0.177) were not found to be dependent on age. The parameters showed no sex differences. The number of eyes with ECD below 1,000 and 2,000 cells per square millimeter was 5 (0.97%) and 130 (25.1%), respectively. CONCLUSIONS: The data from our study emphasize that age, but not gender, is the main determinant of ECD.

Non-compliance with contact lens wear and care practices: a comparative analysis.

PURPOSE: To compare the effects of existing patient awareness of lens-related complications and underlying risk factors on actual patient behavior during contact lens wear and care practices in two different clinical study populations. METHODS: Established contact lens wearers (n = 281) completed an anonymous written questionnaire on presenting to their habitual eye care practitioner in the Dallas-Fort Worth metroplex. Data were analyzed and compared against a second study population, which comprised established contact lens wearers (n = 152) who were sequentially evaluated after their routine contact lens examination at the University of Texas Southwestern Medical Center at Dallas, TX (UTSW). All patients were questioned regarding his or her lens care practices and knowledge of complications and risk factors associated with contact lens wear. RESULTS: Fifty-eight percent of patients in the general community could identify by name a complication associated with lens wear compared with 91% within the medical center. The most frequent complications reported were related to comfort and handling (72%, Dallas-Fort Worth) and infection (47%, UTSW). The majority of patients could correctly identify risk factors associated with lens-related complications; awareness for topping-off solutions, tap water exposure, and hygiene varied between groups. Overall, 85% of patients perceived themselves as compliant with their lens wear and care practices. Using a standard scoring model to determine actual compliance, 2% of patients demonstrated good compliance; however, only 0.4% of patients were fully compliant with contact lens wear and care practices. CONCLUSIONS: The data reveal some study bias in complication and risk awareness between populations; however, despite this limitation, a significant proportion of patients exhibited actual non-compliant behavior despite acknowledged awareness of risk. Although most patients consider themselves to be complying with standard practitioner guidelines for lens wear and care practices, essentially all contact lens wearing patients exhibit behavioral non-compliance with resulting increased risk for significant complications.

Glaucoma in patients with corneal endothelial dystrophy.

OBJECTIVES: The prevalence of primary open-angle glaucoma (POAG) in patients with corneal endothelial dystrophy has not been previously studied. Prevalence of POAG in patients with endothelial dystrophy was compared with that in the general population to determine the presence of a relationship between the diseases. DESIGN: Retrospective case-control study. METHODS: A study of the prevalence of POAG in 430 eyes of 215 patients with endothelial dystrophy was conducted. Patients followed for less than 6 months were excluded. Relative risk of POAG was calculated using age- and race-matched control data from the Baltimore Eye Survey and the Los Angeles Latino Eye Survey for comparison. Ocular hypertension (OHT) and secondary glaucoma (SG) rates after penetrating keratoplasty (PK) and Descemet stripping endothelial keratoplasty (DSEK) were separately analyzed. RESULTS: Relative risk of POAG in white, African American, and Hispanic patients with endothelial dystrophy was 0.94, 2.59, and 3.7, respectively (P = 0.89, 95% confidence interval [CI], -0.028 to 0.0289; P = 0.13; 95% CI, 0.011-0.274; P = 0.055; 95% CI, 0.0423-0.356). Relative risk of SG and combined OHT/SG in PK versus DSEK was 4.15 and 1.95 (P < 0.001; 95% CI, 0.0654-0.322; P = 0.005; 95% CI, 0.116-0.332), respectively. No differences in OHT/SG rates were found comparing PK-triple with PK, DSEK-triple with DSEK, and repeat with primary PK or DSEK (P = 0.98; P = 0.62; P = 0.95; P = 0.87), respectively. CONCLUSIONS: No increased risk of POAG was found in patients with endothelial dystrophy. Increased prevalence of OHT/SG was shown with PK versus DSEK; possible mechanisms include mechanical closure of Schlemm's canal by running suture and prolonged steroid use.

Effects of multipurpose contact lens care solutions and their ingredients on membrane-associated mucins of human corneal epithelial cells.

PURPOSE: Membrane-associated mucins play an important role for protecting epithelial cells at the ocular surface from microbial invasion. The purpose of this study was to determine whether multipurpose solutions (MPSs) for contact lens care and their ingredients alter the expression of membrane-associated mucins in human corneal epithelial (HCE-T) cells. METHODS: SV40-immortalized HCE-T cells were cultured in Dulbecco's modified Eagle medium/F12 medium with 5% fetal bovine serum to confluence and were then exposed to 10% dilutions of five different MPSs, or to their representative ingredients, 0.1% macrogolglycerol hydroxystearate, 0.1% poloxamer, 0.1% poloxamine, 1 and 5 ppm polyhexamethylene biguanide, or 0.05% and 0.1% boric acid for 24 hr. Quantitative real-time polymerase chain reaction was used to investigate the gene expression of MUC1, MUC4, and MUC16. Immunofluorescence staining of MUC16 protein on the surface of the HCE-T cells exposed to 10% diluted MPSs for 24 hr or undiluted MPSs for 30 min was observed by laser confocal scanning microscopy followed by quantitative image analysis. RESULTS: Three MPSs containing boric acid significantly reduced gene expressions of MUC1 from 20.2% to 56.7% (P<0.01). Gene expressions of MUC4 and MUC16 were also reduced by these MPSs; however, there were no significant differences. Among ingredients, 0.1% boric acid significantly reduced gene expressions of MUC1 and MUC16 by 7.4% and 18.9%, respectively (P<0.01). Immunofluorescence microscopy also demonstrated that in undiluted form, three MPSs containing boric acid significantly reduced the expression of MUC16 protein. CONCLUSIONS: The MPSs containing boric acid downregulate membrane-associated mucins as compared with MPSs that do not contain boric acid. There may be some subtle membrane or other interactions between ingredients in lens-care solutions that adversely alter corneal cell mucins.

Patient compliance during contact lens wear: perceptions, awareness, and behavior.

OBJECTIVES: Patient noncompliance with recommended hygienic practices in contact lens wear is often considered a significant risk factor for microbial keratitis and adverse contact lens-related events. Despite advancements in lens materials and care solutions, noncompliant behavior continues to hinder efforts to maximize contact lens safety. The objective of this pilot study was to assess the relationship between perceived and actual compliance with awareness of risk and behavior. METHODS: One hundred sixty-two established contact lens wearers were sequentially evaluated after their routine contact lens examination at the Optometry Clinic at the University of Texas Southwestern Medical Center at Dallas, TX. Each patient was questioned by a single trained interviewer regarding his or her lens care practices and knowledge of risk factors associated with lens wear. RESULTS: Eighty-six percent of patients believed they were compliant with lens wear and care practices; 14% identified themselves as noncompliant. Using a scoring model, 32% demonstrated good compliance, 44% exhibited average compliance, and 24% were noncompliant; age was a significant factor (P = 0.020). Only 34% of patients who perceived themselves as compliant exhibited a good level of compliance (P<0.001). Eighty percent of patients reported an awareness of risk factors, but awareness did not influence negative behavior. Replacing the lens case was the only behavior associated with a positive history for having experienced a prior contact lens-related complication (P = 0.002). CONCLUSIONS: Perceived compliance is not an indicator for appropriate patient behavior. A large proportion of patients remain noncompliant despite awareness of risk. Education alone is not a sufficient strategy to improve behavior; newer approaches aimed at improving compliance with lens care practices are urgently needed.