Shear-Thinning Viscous Materials for Subconjunctival Injection of Microparticles.

While drug-loaded microparticles (MPs) can serve as drug reservoirs for sustained drug release and therapeutic effects, needle clogging by MPs poses a challenge for ocular drug delivery via injection. Two polymers commonly used in ophthalmic procedures-hyaluronic acid (HA) and methylcellulose (MC)-have been tested for their applicability for ocular injections. HA and MC were physically blended with sunitinib malate (SUN)-loaded PLGA MPs for subconjunctival (SCT) injection into rat eyes. The HA and MC viscous solutions facilitated injection through fine-gauged needles due to their shear-thinning properties as shown by rheological characterizations. The diffusion barrier presented by HA and MC reduced burst drug release and extended overall release from MPs. The significant level of MP retention in the conjunctiva tissue post-operation confirmed the minimal leakage of MPs following injection. The safety of HA and MC for ocular applications was demonstrated histologically.

Controlled release of dexamethasone sodium phosphate with biodegradable nanoparticles for preventing experimental corneal neovascularization.

Corneal neovascularization (CNV) leads to the loss of corneal transparency and vision impairment, and can ultimately cause blindness. Topical corticosteroids are the first line treatment for suppressing CNV, but poor ocular bioavailability and rapid clearance of eye drops makes frequent administration necessary. Patient compliance with frequent eye drop application regimens is poor. We developed biodegradable nanoparticles (NP) loaded with dexamethasone sodium phosphate (DSP) using zinc ion bridging, DSP-Zn-NP, with dense coatings of poly(ethylene glycol) (PEG). DSP-Zn-NP were safe and capable of providing sustained delivery of DSP to the front of the eye following subconjunctival (SCT) administration in rats. We reported that a single SCT administration of DSP-Zn-NP prevented suture-induced CNV in rats for two weeks. In contrast, the eyes receiving SCT administration of either saline or DSP solution developed extensive CNV in less than 1 week. SCT administration of DSP-Zn-NP could be an effective strategy in preventing and treating CNV.

Autologous serum eye drops for dry eye.

BACKGROUND: Theoretically, autologous serum eye drops (AS) offer a potential advantage over traditional therapies on the assumption that AS not only serve as a lacrimal substitute to provide lubrication but contain other biochemical components that allow them to mimic natural tears more closely. Application of AS has gained popularity as second-line therapy for patients with dry eye. Published studies on this subject indicate that autologous serum could be an effective treatment for dry eye. OBJECTIVES: We conducted this review to evaluate the efficacy and safety of AS given alone or in combination with artificial tears as compared with artificial tears alone, saline, placebo, or no treatment for adults with dry eye. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 5), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to July 2016), Embase (January 1980 to July 2016), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to July 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We also searched the Science Citation Index Expanded database (December 2016) and reference lists of included studies. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 5 July 2016. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that compared AS versus artificial tears for treatment of adults with dry eye. DATA COLLECTION AND ANALYSIS: Two review authors independently screened all titles and abstracts and assessed full-text reports of potentially eligible trials. Two review authors extracted data and assessed risk of bias and characteristics of included trials. We contacted investigators to ask for missing data. For both primary and secondary outcomes, we reported mean differences with corresponding 95% confidence intervals (CIs) for continuous outcomes. We did not perform meta-analysis owing to differences in outcome assessments across trials. MAIN RESULTS: We identified five eligible RCTs (92 participants) that compared AS versus artificial tears or saline in individuals with dry eye of various origins (Sjögren's syndrome-related dry eye, non-Sjögren's syndrome dry eye, and postoperative dry eye induced by laser-assisted in situ keratomileusis (LASIK)). We assessed the certainty of evidence as low or very low because of lack of reporting of quantitative data for most outcomes and unclear or high risk of bias among trials. We judged most risk of bias domains to have unclear risk in two trials owing to insufficient reporting of trial characteristics, and we considered one trial to have high risk of bias for most domains. We judged the remaining two trials to have low risk of bias; however, these trials used a cross-over design and did not report data in a way that could be used to compare outcomes between treatment groups appropriately. Incomplete outcome reporting and heterogeneity among outcomes and follow-up periods prevented inclusion of these trials in a summary meta-analysis.Three trials compared AS with artificial tears; however, only one trial reported quantitative data for analysis. Low-certainty evidence from one trial suggested that AS might provide some improvement in participant-reported symptoms compared with artificial tears after two weeks of treatment; the mean difference in mean change in symptom score measured on a visual analogue scale (range 0 to 100, with higher scores representing worse symptoms) was -12.0 (95% confidence interval (CI) -20.16 to -3.84; 20 participants). This same trial found mixed results with respect to ocular surface outcomes; the mean difference in mean change in scores between AS and artificial tears was -0.9 (95% CI -1.47 to -0.33; 20 participants; low-certainty evidence) for fluorescein staining and -2.2 (95% CI -2.73 to -1.67; 20 participants; low-certainty evidence) for Rose Bengal staining. Both staining scales range from 0 to 9, with higher scores indicating worse results. The mean change in tear film break-up time was 2.00 seconds longer (95% CI 0.99 to 3.01; 20 participants; low-certainty evidence) in the AS group than in the artificial tears group. Investigators reported no clinically meaningful differences in Schirmer's test scores between groups (mean difference -0.40 mm, 95% CI -2.91 to 2.11; 20 participants; low-certainty evidence). None of these three trials reported tear hyperosmolarity and adverse events.Two trials compared AS versus saline; however, only one trial reported quantitative data for analysis of only one outcome (Rose Bengal staining). Trial investigators of the two studies reported no differences in symptom scores, fluorescein staining scores, tear film break-up times, or Schirmer's test scores between groups at two to four weeks' follow-up. Very low-certainty evidence from one trial suggested that AS might provide some improvement in Rose Bengal staining scores compared with saline after four weeks of treatment; the mean difference in Rose Bengal staining score (range from 0 to 9, with higher scores showing worse results) was -0.60 (95% CI -1.11 to -0.09; 35 participants). Neither trial reported tear hyperosmolarity outcomes. One trial reported adverse events; two of 12 participants had signs of conjunctivitis with negative culture that did resolve. AUTHORS' CONCLUSIONS: Overall, investigators reported inconsistency in possible benefits of AS for improving participant-reported symptoms and other objective clinical measures. There might be some benefit in symptoms with AS compared with artificial tears in the short-term, but we found no evidence of an effect after two weeks of treatment. Well-planned, large, high-quality RCTs are warranted to examine participants with dry eye of different severities by using standardized questionnaires to measure participant-reported outcomes, as well as objective clinical tests and objective biomarkers to assess the benefit of AS therapy for dry eye.

Longitudinal Study of Age-Related Cataract Using Dynamic Light Scattering: Loss of α-Crystallin Leads to Nuclear Cataract Development.

PURPOSE: To conduct a longitudinal study on age-related nuclear cataracts using dynamic light scattering (DLS) to determine if cataract progression is associated with loss of the unbound form of the lens molecular chaperone protein, α-crystallin. DESIGN: Natural history and cohort study. PARTICIPANTS: Patients 30 years of age or older of either gender seeking treatment at the Wilmer Eye Institute Cornea-Cataract Department. METHODS: All patients underwent a comprehensive dilated eye examination every 6 months, including slit-lamp grading of their lenses using the Age-Related Eye Disease Study (AREDS) clinical lens grading system and obtaining an estimate of unbound α-crystallin level in the nucleus, the α-crystallin index (ACI), using the National Aeronautics and Space Administration-National Eye Institute DLS device. We used a random effects statistical model to examine the relationship of lens opacity changes over time with ACI changes. MAIN OUTCOME MEASURES: α-Crystallin Index (ACI) and AREDS nuclear cataract grade. RESULTS: Forty-five patients (66 eyes) 34 to 79 years of age with AREDS nuclear lens grades of 0 to 3.0 were followed up every 6 months for a mean of 19 months (range, 6-36 months). We found that lenses with the lowest baseline levels of ACI had the most rapid progression of cataracts, whereas lenses with higher ACI at baseline had no or slower cataract progression. Lenses that lost α-crystallin at the highest rates during the study also had faster progression of nuclear cataracts than lenses with a slower rate of ACI loss. Kaplan-Meier survival curves showed that lenses with the lowest initial ACI had the highest risk of undergoing cataract surgery. CONCLUSIONS: This longitudinal study corroborates our previous cross-sectional study finding that higher levels of unbound α-crystallin as assessed by ACI are associated with lower risk of cataract formation and that loss of ACI over time is associated with cataract formation and progression. This study suggested that assessment of ACI with the DLS device could be used as a surrogate for lens opacity risk in clinical studies, and for assessing nuclear cataract events in studies where cataract development may be a side effect of a drug or device.

Autologous serum eye drops for dry eye.

BACKGROUND: =Theoretically, autologous serum eye drops (AS) have a potential advantage over traditional therapies based on the assumption that ASserve not only as a lacrimal substitute to provide lubrication, but also contain other biochemical components mimicking natural tears more closely. The application of AS in dry eye treatment has gained popularity as a second-line therapy in the treatment of dry eye.Published studies on the subject indicate that autologous serum could be an effective treatment for dry eye. OBJECTIVES: To evaluate the efficacy and safety of AS compared to artificial tears for treating dry eye. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 3),Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE,(January 1950 to April 2013), EMBASE (January 1980 to April 2013), Latin American and Caribbean Literature on Health Sciences(LILACS) (January 1982 to April 2013), themetaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov(www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We also searched the Science Citation Index Expanded database (September 2013) and reference lists of included studies. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 15 April 2013. SELECTION CRITERIA: We included randomized controlled trials (RCTs) in which AS was compared to artificial tears in the treatment of dry eye in adults. DATA COLLECTION AND ANALYSIS: Two review authors independently screened all titles and abstracts and assessed full-text articles of potentially eligible trials. Two review authors extracted data and assessed the methodological quality and characteristics of the included trials.We contacted investigators for missing data. For both primary and secondary outcomes, we reported mean differences with corresponding 95% confidence intervals(CIs) for continuous outcomes. MAIN RESULTS: We identified four eligible RCTs in which AS was compared with artificial tear treatment or saline in individuals (n = 72 participants)with dry eye of various etiologies (Sjögren's syndrome-related dry eye, non-Sjögren's syndrome dry eye and postoperative dry eye induced by laser-assisted in situ keratomileusis (LASIK)). The quality of the evidence provided by these trials was variable. A majority of the risk of bias domains were judged to have an unclear risk of bias in two trials owing to insufficient reporting of trial characteristics.One trial was considered to have a low risk of bias for most domains while another was considered to have a high risk of bias for most domains. Incomplete outcome reporting and heterogeneity in the participant populations and follow-up periods prevented the inclusion of these trials in a summary meta-analysis. For the primary outcome, improvement in participant-reported symptoms at one month, one trial (12 participants) showed no difference in participant-reported symptoms between 20% AS and artificial tears. Based on the results of two trials in 32 participants, 20% AS may provide some improvement in participant-reported symptoms compared to traditional artificial tears after two weeks of treatment. One trial also showed positive results with a mean difference in tear breakup time (TBUT) of 2.00 seconds (95% CI 0.99 to 3.01 seconds) between 20% AS and artificial tears after two weeks, which were not similar to findings from the other trials. Based on all other objective clinical assessments included in this review, AS was not associated with improvements in aqueous tear production measured by Schirmer's test (two trials, 33 participants), ocular surface condition with fluorescein (four trials, 72 participants) or Rose Bengal staining (three trials, 60 participants), and epithelial metaplasia by impression cytology compared to artificial tears (one trial, 12 participants). Data on adverse effects were not reported by three of the included studies. In one study, there were no serious adverse events reported with the collection of and treatment with AS. AUTHORS' CONCLUSIONS: Overall there was inconsistency in the possible benefits of AS in improving participant-reported symptoms and TBUT and lack of effect based on other objective clinical measures. Well-planned, large, high-quality RCTs are warranted, in different severities of dry eye and using standardized questionnaires to measure participant-reported outcomes and objective clinical tests as well as objective biomarkers to assess the benefit of AS therapy for dry eye.

ßA3/A1-crystallin is required for proper astrocyte template formation and vascular remodeling in the retina.

Nuc1 is a spontaneous rat mutant resulting from a mutation in the Cryba1 gene, coding for ßA3/A1-crystallin. Our earlier studies with Nuc1 provided novel evidence that astrocytes, which express ßA3/A1-crystallin, have a pivotal role in retinal remodeling. The role of astrocytes in the retina is only beginning to be explored. One of the limitations in the field is the lack of appropriate animal models to better investigate the function of astrocytes in retinal health and disease. We have now established transgenic mice that overexpress the Nuc1 mutant form of Cryba1, specifically in astrocytes. Astrocytes in wild type mice show normal compact stellate structure, producing a honeycomb-like network. In contrast, in transgenics over-expressing the mutant (Nuc1) Cryba1 in astrocytes, bundle-like structures with abnormal patterns and morphology were observed. In the nerve fiber layer of the transgenic mice, an additional layer of astrocytes adjacent to the vitreous is evident. This abnormal organization of astrocytes affects both the superficial and deep retinal vascular density and remodeling. Fluorescein angiography showed increased venous dilation and tortuosity of branches in the transgenic retina, as compared to wild type. Moreover, there appear to be fewer interactions between astrocytes and endothelial cells in the transgenic retina than in normal mouse retina. Further, astrocytes overexpressing the mutant ßA3/A1-crystallin migrate into the vitreous, and ensheath the hyaloid artery, in a manner similar to that seen in the Nuc1 rat. Together, these data demonstrate that developmental abnormalities of astrocytes can affect the normal remodeling process of both fetal and retinal vessels of the eye and that ßA3/A1-crystallin is essential for normal astrocyte function in the retina.

Hypopyon uveitis following LASIK in a patient with ulcerative colitis.

PURPOSE: To present a case of unilateral hypopyon uveitis that began 15 days after uneventful bilateral LASIK in a 24-year-old man with an undisclosed history of ulcerative colitis. METHODS: Case report. RESULTS: The hypopyon uveitis completely resolved after treatment with aggressive topical and oral steroid agents in combination with topical antibiotic coverage. CONCLUSIONS: Although rare, visually significant hypopyon uveitis may arise after LASIK in the setting of ulcerative colitis and positive human leukocyte antigen (HLA) B27. Early recognition and treatment can result in an excellent outcome. The exact relationship between hypopyon uveitis and LASIK is impossible to ascertain.

Descemet-stripping automated endothelial keratoplasty: a successful alternative to repeat penetrating keratoplasty.

BACKGROUND: Although Descemet-stripping automated endothelial keratoplasty has replaced penetrating keratoplasty for primary treatment of endothelial disorders, many patients have already undergone penetrating keratoplasty. It is unclear when repeat penetrating keratoplasty is necessary or when endothelial keratoplasty may restore clarity to a failed graft. DESIGN: Retrospective case series of patients undergoing Descemet-stripping automated endothelial keratoplasty after penetrating keratoplasty by three surgeons at an academic tertiary care centre. PARTICIPANTS: Eight patients with Descemet-stripping automated endothelial keratoplasty after penetrating keratoplasty from 2006 to 2009. METHODS: Microkeratome-prepared Descemet-stripping automated endothelial keratoplasty donor tissue was used. In seven cases, the penetrating keratoplasty bed was neither stripped nor scraped, and in one, scraping only was performed. MAIN OUTCOME MEASURES: Preoperative and 6-month postoperative best-corrected visual acuities in logMAR (logarithm of the minimum angle of resolution). RESULTS: The average pre-Descemet-stripping automated endothelial keratoplasty best-corrected visual acuity was 1.375, and the average best-corrected visual acuity 6months postoperatively was logMAR 1.0, a 2.5-fold improvement in the minimum angle of resolution (P=0.22). Seven of the eight patients showed an improvement in best-corrected visual acuity, and one patient had failure of Descemet-stripping automated endothelial keratoplasty and required penetrating keratoplasty. Five had a postoperative event: one had a gap that resolved spontaneously, three required rebubblings (injections of air only without otherwise repositioning the graft), and one experienced graft failure. CONCLUSIONS: Descemet-stripping automated endothelial keratoplasty can successfully rescue a prior penetrating keratoplasty, even with a fairly high detachment rate. Given these favourable visual outcomes, further study of this promising strategy is justified.

Sunitinib malate-loaded biodegradable microspheres for the prevention of corneal neovascularization in rats.

Corneal neovascularization (NV) predisposes patients to compromised corneal transparency and visional acuity. Sunitinib malate (Sunb-malate) targeting against multiple receptor tyrosine kinases, exerts potent antiangiogenesis. However, the rapid clearance of Sunb-malate eye drops administered through topical instillation limits its therapeutic efficacy and poses a challenge for potential patient compliance. Sunb-malate, the water-soluble form of sunitinib, was shown to have higher intraocular penetration through transscleral diffusion following subconjunctival (SCT) injection in comparison to its sunitinib free base formulation. However, it is difficult to load highly water-soluble drugs and achieve sustained drug release. We developed Sunb-malate loaded poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres (Sunb-malate MS) with a particle size of approximately 15 µm and a drug loading of 7 wt%. Sunb-malate MS sustained the drug release for 30 days under the in vitro infinite sink condition. Subconjunctival (SCT) injection of Sunb-malate MS provided a prolonged ocular drug retention and did not cause ocular toxicity at a dose of 150 µg of active agent. Sunb-malate MS following SCT injection more effectively suppressed the suture-induced corneal NV than either Sunb-malate free drug or the placebo MS. Local sustained release of Sunb-malate through the SCT injection of Sunb-malate MS mitigated the proliferation of vascular endothelial cells and the recruitment of mural cells into the cornea. Moreover, the gene upregulation of proangiogenic factors induced by the pathological process was greatly neutralized by SCT injection of Sunb-malate MS. Our findings provide a sustained release platform for local delivery of tyrosine kinase inhibitors to treat corneal NV.

A clinicopathologic series of primary graft failure after Descemet's stripping and automated endothelial keratoplasty.

PURPOSE: To characterize the clinical and histologic features of primary graft failure after Descemet's stripping and automated endothelial keratoplasty (DSAEK). DESIGN: Retrospective observational case series. PARTICIPANTS: Sixteen cases of DSAEK graft failure from 15 patients, all with detailed histologic examination of failed graft tissue. METHODS: Hematoxylin-eosin, periodic acid-Schiff staining, and light microscopy were used to examine the failed DSAEK graft tissue from all patients. MAIN OUTCOME MEASURES: Examination of specimens for corneal endothelial cell viability and host-donor interface characteristics. RESULTS: Clinical history revealed that 88% (14/16) of studied DSAEK grafts detached before failure, and pathologic examination found that 75% (12/16) of failed grafts had atrophic corneal endothelium. Examples of residual host Descemet's membrane in the graft site and improper donor trephination were also identified. CONCLUSIONS: Marked loss of the corneal endothelium is the prominent feature of primary DSAEK graft failure. Examples of surgical features, such as incomplete Descemet's stripping and residual full-thickness cornea with a DSAEK graft, are shown.

Tissue-derived microparticles reduce inflammation and fibrosis in cornea wounds.

Biological materials derived from the extracellular matrix (ECM) of tissues serve as scaffolds for rebuilding tissues and for improved wound healing. Cornea trauma represents a wound healing challenge as the default repair pathway can result in fibrosis and scar formation that limit vision. Effective treatments are needed to reduce inflammation, promote tissue repair, and retain the tissue's native transparency and vision capacity. Tissue microparticles derived from cornea, cartilage and lymph nodes were processed and screened in vitro for their ability to reduce inflammation in ocular surface cells isolated from the cornea stroma, conjunctiva, and lacrimal gland. Addition of ECM particles to the media reduced expression of inflammatory genes and restored certain tear film protein production in vitro. Particles derived from lymph nodes were then applied to a rabbit lamellar keratectomy corneal injury model. Application of the tissue particles in a fibrin glue carrier decreased expression of inflammatory and fibrotic genes and scar formation as measured through imaging, histology and immunohistochemistry. In sum, immunomodulatory tissue microparticles may provide a new therapeutic tool for reducing inflammation in the cornea and ocular surface and promoting tissue repair. STATEMENT OF SIGNIFICANCE: Damaged cornea will result in scar tissue formation that impedes vision, and new therapies are needed to enhance wound healing in the cornea and to prevent fibrosis. We evaluated the effects of biological scaffolds derived extracellular matrix (ECM) during corneal wound healing. These ECM particles reduced inflammatory gene expression and restored tear film production in vitro, and reduced scar formation and fibrosis genes in the wounded cornea, when applied to in vivo lamellar keratectomy injury model. The immunomodulatory tissue microparticles may provide a new therapeutic tool for reducing inflammation in the cornea and ocular surface and promoting proper tissue repair.

Controlled release of corticosteroid with biodegradable nanoparticles for treating experimental autoimmune uveitis.

Noninfectious uveitis is a potentially blinding ocular condition that often requires treatment with corticosteroids to prevent inflammation-related ocular complications. Severe forms of uveitis such as panuveitis that affects the whole eye often require a combination of topical and either regional or systemic corticosteroid. Regional corticosteroids are currently delivered inside the eye by intravitreal injection (e.g. Ozurdex®, an intravitreal dexamethasone implant). Intravitreal injection is associated with rare but potentially serious side effects, including endophthalmitis, retinal and vitreous hemorrhage, and retinal detachment. Subconjunctival (SCT) injection is a less invasive option that is a common route used for post-surgical drug administration and treatment of infection and severe inflammation. However, it is the water soluble form of dexamethasone, dexamethasone sodium phosphate (DSP), that has been demonstrated to achieve high intraocular penetration with subconjunctival injection. It is difficult to load highly water soluble drugs, such as DSP, and achieve sustained drug release using conventional encapsulation methods. We found that use of carboxyl-terminated poly(lactic-co-glycolic acid) (PLGA) allowed encapsulation of DSP into biodegradable nanoparticles (NP) with relatively high drug content (6% w/w) if divalent zinc ions were used as an ionic "bridge" between the PLGA and DSP. DSP-Zn-NP had an average diameter of 210 nm, narrow particle size distribution (polydispersity index ~0.1), and near neutral surface charge (-9 mV). DSP-Zn-NP administered by SCT injection provided detectable DSP levels in both the anterior chamber and vitreous chamber of the eye for at least 3 weeks. In a rat model of experimental autoimmune uveitis (EAU), inflammation was significantly reduced in both the front and back of the eye in animals that received a single SCT injection of DSP-Zn-NP as compared to animals that received either aqueous DSP solution or phosphate buffered saline (PBS). DSP-Zn-NP efficacy was evidenced by a reduced clinical disease score, decreased expression of various inflammatory cytokines, and preserved retinal structure and function. Furthermore, SCT DSP-Zn-NP significantly reduced microglia cell density in the retina, a hallmark of EAU in rats. DSP-Zn-NP hold promise as a new strategy to treat noninfectious uveitis and potentially other ocular inflammatory disorders.

Electron microscopic investigation of the lens capsule and conjunctival tissues in individuals with clinically unilateral pseudoexfoliation syndrome.

PURPOSE: To determine the presence of pseudoexfoliative material in the unaffected eyes of patients with clinically unilateral pseudoexfoliation syndrome. DESIGN: Prospective observational case series. PARTICIPANTS: Thirty-two consecutive patients with clinically unilateral pseudoexfoliation syndrome, undergoing routine cataract surgery. METHODS: Transmission electron microscopy (TEM) was used to examine conjunctival and anterior lens capsule specimens in affected and unaffected eyes. MAIN OUTCOME MEASURE: Presence of characteristic pseudoexfoliation syndrome findings on TEM. RESULTS: Transmission electron microscopy demonstrated pseudoexfoliative material on either the anterior capsule or conjunctival sample from the clinically unaffected eye in 26 of the 32 patients with clinically unilateral pseudoexfoliation syndrome (81%; 95% confidence interval, 64%-93%). CONCLUSION: The results suggest that the seemingly uninvolved eye in a patient with clinically unilateral pseudoexfoliation syndrome has an 81% likelihood of being affected ultrastructurally. Several population studies examining conversion rates from unilateral to bilateral disease have found a similar proportion of patients with bilateral pseudoexfoliation syndrome in the later decades of life.

Assessment of eye bank-prepared posterior lamellar corneal tissue for endothelial keratoplasty.

OBJECTIVE: To evaluate eye bank-prepared tissue for Descemet's stripping automated endothelial keratoplasty (DSAEK). DESIGN: Experimental study and retrospective case series. PARTICIPANTS: Seventeen human donor corneas and 4 recipient patients undergoing DSAEK surgery. METHODS: Corneal-scleral discs were obtained. Specular microscopy and pachymetry were performed. A designated Tissue Banks International technician used a microkeratome to prepare a flap. Posterior bed thickness was measured. The sectioned tissue was stored, and at 24 and 48 hours, pachymetry was repeated. At 48 hours, specular microscopy was repeated, and endothelial cell viability was assessed with trypan blue. Descemet's stripping automated endothelial keratoplasty was performed in 4 patients using eye bank-prepared posterior lamellar tissue. MAIN OUTCOME MEASURES: Corneal tissue was assessed with the following parameters: corneal thickness measured with ultrasonic pachymetry, cell density counts measured with a keratoanalyzer, and cell viability as observed with trypan blue exclusion. Patient outcomes were measured by changes in visual acuity (VA) and the presence of a clear graft. RESULTS: Donor corneal pachymetry before sectioning averaged 599+/-52 microm. Immediately after sectioning with a microkeratome set at a depth of 300 microm, mean posterior bed thickness was 328+/-95 microm. Thus, the mean cutting depth achieved by the microkeratome when set at 300 micrometers averaged 271+/-83 microm. After storage for 24 hours, the posterior beds measured 352 microm, an average swelling of 24 (7%) microm (P = 0.14). After 48 hours, the posterior beds measured 382 microm, an average swelling of 54 (16%) microm (P = 0.02). Cell counts 48 hours after sectioning decreased by an average of 11% (P = 0.10). Endothelial cell staining confirmed improvement in postsectioning morphology and survival with increased technician experience. All 4 patients receiving eye bank-prepared DSAEK tissue showed uncomplicated postoperative results, with improvement in VA. CONCLUSIONS: The microkeratome cutting depth was moderately accurate. Pachymetry, cell density, and cell viability of sectioned tissue after 48 hours in storage were encouraging overall. Initial clinical results of eye bank-prepared DSAEK tissue showed uncomplicated postoperative courses and improved VA. Additional studies are needed to follow the long-term outcomes in the recipients of these tissues.

Dynamics of small-incision clear cornea wounds after phacoemulsification surgery using optical coherence tomography in the early postoperative period.

PURPOSE: To evaluate wound dynamics in the immediate postoperative period after phacoemulsification surgery using a small-incision clear cornea approach. METHODS: Eight patients underwent standard postoperative evaluation 24 hours after uneventful phacoemulsification surgery performed through a temporal or nasal clear corneal incision. Additional screening was performed with non-contact optical coherence tomography (Visante Anterior Segment OCT) to examine the corneal wounds. RESULTS: One patient showed partial spontaneous gaping in different areas of the incision, undetected at slit-lamp evaluation. This patient presented with a mild senile bilateral ptosis. Another patient showed localized gaping of the internal aspect of the corneal wound. Both patients had intraocular pressures of 10 mmHg, which were the lowest pressures recorded in the group. Four other incisions showed some degree of localized Descemet's membrane detachment in the vicinity of the wound, also undetected by slit-lamp evaluation. CONCLUSIONS: Small-incision clear cornea wounds may gape in the immediate postoperative period. If the gape occurs along the entire length of the wound, it may lead to inadvertent bacterial access into the anterior chamber. Optical coherence tomography also indicates that localized detachment of Descemet's membrane may be more common than observed with slit-lamp microscopy.

Anesthetic keratopathy after photorefractive keratectomy.

We report a case of anesthetic keratopathy after photorefractive keratectomy (PRK) and physician-prescribed topical anesthetic agents. After PRK for hyperopic correction, the patient was sent home with a bandage contact lens and instructions to use anesthetic eyedrops and take oral pain medications after surgery. During the first postoperative week, the eyes did not reepithelialize and bilateral perilimbal infiltrates developed. Cultures were negative and failed to clear with fortified antibiotic agents. On careful questioning, the patient admitted to instilling diluted tetracaine (0.05%) as needed in both eyes. She was instructed to stop the anesthetic agent labeled as "comfort drops" and the fortified antibiotics and start topical steroids. Soon after, the eyes reepithelialized and the infiltrates cleared. This case demonstrates the potential for anesthetic keratopathy in PRK patients.

Factors Associated With Graft Rejection in the Cornea Preservation Time Study.

PURPOSE: To identify factors related to graft rejection following Descemet stripping automated endothelial keratoplasty (DSAEK) in the Cornea Preservation Time Study (CPTS). DESIGN: Cohort study within a multicenter randomized clinical trial. METHODS: A total of 1330 eyes of 1090 subjects undergoing DSAEK were randomized to receive a donor cornea with preservation time (PT) of 0-7 days (n = 675) or 8-14 days (n = 655) and followed for 3 years. Central endothelial cell density (ECD) was determined by a central image analysis reading center. Multivariable Cox models adjusted for PT, recipient diagnosis, and surgeon effect were used to identify factors associated with rejection. RESULTS: Cumulative probability of definite graft rejection was 3.6% (99% confidence interval 2.5%-5.3%). Younger recipient age was associated with graft rejection (P < .001; hazard ratio: 0.53 [0.33, 0.83] per decade). PT, donor-recipient sex mismatch, recipient diagnosis, recipient race, graft size, discontinuation of topical corticosteroids and immune-modulators, prior immunizations within 3 months, and prior glaucoma surgery were not associated with rejection (P > .01). Among clear grafts with an ECD measurement at baseline and 3 years (n = 913), endothelial cell loss (ECL) was greater in eyes that experienced a rejection episode (n = 27) than in those that did not (n = 886) (48% vs 38%, P = .03). Twelve of 44 eyes (27%) with definite graft rejection subsequently failed, comprising 15% of the 79 failures in the CPTS. CONCLUSIONS: Graft rejection is uncommon after DSAEK and more likely with younger age, in a study cohort mostly > 50 years old. Rejection increases ECL, but it is not a leading cause of DSAEK failure.

Cryopreservation and lentiviral-mediated genetic modification of human primary cultured corneal endothelial cells.

PURPOSE: To determine the viability and potential usefulness of cryopreserved human primary cultured corneal endothelial cells by characterizing their morphology, gene expression, and ability for genetic modification by the lentiviral vector equine infectious anemia virus (EIAV). METHODS: Primary cultured endothelial cells were dissociated from human corneas and grown in organ culture medium. Corneal endothelial cell origin was confirmed by morphology and immunostaining with polyclonal anti-collagen VIII antibodies. Cells of different passages were cryopreserved in medium containing dimethyl sulfoxide and were assessed after thawing for morphology, proliferative capacity, gene expression, and ability to form cell-cell junctions. EIAV encoding enhanced green fluorescent protein (eGFP) was used to transduce cryopreserved human corneal endothelial cells. Transduced cells were then sorted by fluorescence-activated cell sorting (FACS) and imaged with fluorescence microscopy. RESULTS: Cryopreserved, primary, cultured human corneal endothelial cells are viable and retain their ability to proliferate, produce collagen VIII, and express ZO-1, a tight-junction protein. EIAV-based gene transfer of eGFP is highly efficient and nontoxic to cryopreserved human primary cultured corneal endothelial cells. These genetically modified cells can be selected to nearly pure populations with FACS sorting. CONCLUSIONS: Human primary cultured corneal endothelial cells retain their phenotypic properties after cryopreservation. The ability to store, genetically modify, and sort these cells through FACS to pure populations has the potential to greatly expand their future therapeutic application to treat corneal endothelial disorders.

Subluxation of suture-fixated posterior chamber intraocular lenses a clinicopathologic study.

PURPOSE: To report the occurrence of subluxation of suture-fixated posterior chamber (PC) intraocular lenses (IOL) and elucidate the mechanisms involved. DESIGN: Prospective clinicopathologic study. PARTICIPANTS: A single 10-0 Prolene suture explanted from a patient who experienced subluxation of his PC-IOL, 11.5 years after placement. Furthermore, multiple 10-0 Prolene sutures and PC-IOLs used for iris fixation were studied as controls. METHODS: Scanning electron microscopy (SEM) was used to analyze the surface of the explanted suture. In addition, randomly selected 10-0 Prolene sutures cut with Vannas scissors and cut with the positioning holes of a randomly selected PC-IOL identical to that implanted in the patient's eye were examined as controls. Finally, the positioning holes of several randomly selected, iris-fixated PC-IOLs were studied using SEM with particular attention to surface quality and edge finish. MAIN OUTCOME MEASURES: Presence of any signs of suture degradation, the character of the cut edge of the suture, as well as the characteristics of the positioning holes of the PC-IOLs. RESULTS: Scanning electron microscopy of the explanted suture revealed sharply cut edges, without significant degradation of the suture, and no intact loop. Scanning electron microscopy of the control suture cut with a PC-IOL demonstrated a similarly cut edge. The positioning holes of the examined PC-IOLs had a sharp edge, and some also had an imperfect finish. CONCLUSION: We conclude that the surface properties of the positioning holes lead to cutting of the suture, and subsequent subluxation of the PC-IOL.

Advanced glycation end products and receptors in Fuchs' dystrophy corneas undergoing Descemet's stripping with endothelial keratoplasty.

PURPOSE: To describe the histopathologic features of Descemet's membrane (DM) obtained from Fuchs' endothelial corneal dystrophy (FECD) corneas undergoing Descemet's stripping with endothelial keratoplasty (DSEK) and to assess the presence of advanced glycation end products (AGEs) and their receptors in FECD endothelium and DM. DESIGN: Prospective observational case series. PARTICIPANTS: Five eyes of 5 patients undergoing DSEK for FECD and 4 normal control eyebank corneas. METHODS: Descemet's membrane and corneal endothelium from FECD patients undergoing DSEK were assessed with hematoxylin-eosin staining and immunohistochemistry for AGEs, receptor of AGEs (RAGE), and galectin 3 (AGE-R3). MAIN OUTCOME MEASURES: Histopathologic abnormalities and presence of AGEs, RAGE, and AGE-R3 in DSEK specimens. RESULTS: Histopathologic assessment of DSEK specimens from FECD patients disclosed thickening and nodularity of DM and loss of endothelial cells. Immunohistochemical staining of FECD DM for AGE, RAGE, and AGE-R3 showed an abundance of AGEs in the anterior portion of DM, mild positivity for RAGE, and moderate positivity for AGE-R3. CONCLUSIONS: Tissue quality after DSEK is sufficient to allow detailed histopathologic analysis. The presence of AGEs, RAGE, and AGE-R3 in DM and corneal endothelium of FECD patients supports a link between accumulation of AGEs, oxidative stress, and corneal endothelial cell apoptosis in the pathogenesis of FECD.