Predictors of Receiving Keratoplasty for Fuchs' Endothelial Corneal Dystrophy among Medicare Beneficiaries.

PURPOSE: To identify factors associated with receipt of endothelial keratoplasty (EK) and penetrating keratoplasty (PK) in patients with Fuchs' endothelial corneal dystrophy (FECD). DESIGN: Retrospective cohort study. PARTICIPANTS: Medicare beneficiaries 65 years of age or older with a FECD diagnosis between 2011 and 2019. METHODS: The 100% Medicare fee-for-service administrative claims database was queried for treatment-naïve FECD patients. A multivariate logistic regression model including age, race and ethnicity, sex, geography, ocular comorbidities and surgeries, Charlson comorbidity index (CCI), and socioeconomic status was used to identify factors associated with receipt of EK and PK. Kaplan-Meier survival analyses were used to determine the rate of EK after cataract or complex or other anterior segment surgery. MAIN OUTCOME MEASURES: Factors associated with receipt of an EK or PK, plus rate of EK after cataract or complex or other anterior segment surgery. RESULTS: Of 719 066 beneficiaries identified, 31 372 (4.4%) received an EK and 2426 (0.3%) received a PK. In a multivariate analysis, female sex decreased likelihood of both EK and PK (adjusted odds ratio 0.83 [95% confidence interval 0.81-0.85] and 0.84 [0.78-0.92], respectively), while Western residence (1.33 [1.29-1.38]; 1.25 [1.11-1.42]) compared to Southern and history of complex or other anterior segment surgery (1.62 [1.54-1.70]; 5.52 [4.97-6.12]) increased the likelihood of both. Compared to Whites, the likelihood of EK was decreased for Black (0.76 [0.72-0.80]), Asian or Pacific Islander (0.54 [0.48-0.61]), and Hispanic or Latino (0.62 [0.55-0.70]) race and ethnicity, while for the same groups likelihood of PK was increased (for Black 1.32 [1.14-1.53]; Asian/Pacific Islander 1.46 [1.13-1.89]; and Hispanic/Latino 1.62 [1.25-2.11]). Following cataract or complex/other anterior segment surgery, rates of EK were 1.3% and 3.3% at 1 year and 2.3% and 5.6% at 8 years, respectively. CONCLUSIONS: In a multivariate analysis, women beneficiaries are less likely to receive EK or PK for FECD compared with men, whereas non-White beneficiaries are less likely to receive EK and more likely to receive PK compared with White beneficiaries.

A Longitudinal Study of Ebola Sequelae in Liberia.

BACKGROUND: Multiple health problems have been reported in survivors of Ebola virus disease (EVD). Attribution of these problems to the disease without a control group for analysis is difficult. METHODS: We enrolled a cohort of EVD survivors and their close contacts and prospectively collected data on symptoms, physical examination findings, and laboratory results. A subset of participants underwent ophthalmologic examinations. Persistence of Ebola virus (EBOV) RNA in semen samples from survivors was determined. RESULTS: A total of 966 EBOV antibody-positive survivors and 2350 antibody-negative close contacts (controls) were enrolled, and 90% of these participants were followed for 12 months. At enrollment (median time to baseline visit, 358 days after symptom onset), six symptoms were reported significantly more often among survivors than among controls: urinary frequency (14.7% vs. 3.4%), headache (47.6% vs. 35.6%), fatigue (18.4% vs. 6.3%), muscle pain (23.1% vs. 10.1%), memory loss (29.2% vs. 4.8%), and joint pain (47.5% vs. 17.5%). On examination, more survivors than controls had abnormal abdominal, chest, neurologic, and musculoskeletal findings and uveitis. Other than uveitis (prevalence at enrollment, 26.4% vs. 12.1%; at year 1, 33.3% vs. 15.4%), the prevalence of these conditions declined during follow-up in both groups. The incidence of most symptoms, neurologic findings, and uveitis was greater among survivors than among controls. EBOV RNA was detected in semen samples from 30% of the survivors tested, with a maximum time from illness to detection of 40 months. CONCLUSIONS: A relatively high burden of symptoms was seen in all participants, but certain symptoms and examination findings were more common among survivors. With the exception of uveitis, these conditions declined in prevalence during follow-up in both groups. Viral RNA in semen persisted for a maximum of 40 months. (Funded by the National Institute of Allergy and Infectious Diseases and the National Eye Institute; PREVAIL III ClinicalTrials.gov number, NCT02431923.).

Interplays between changing biophysical and social dynamics under climate change: Implications for limits to sustainable adaptation in food systems.

Climate change scenarios have significant implications for the livelihoods and food security of particular groups in society and will necessitate a range of adaptation actions. While there is a significant literature on the social as well as biophysical factors and limits to adaptation, less is known about the interactions between these, and what such interactions mean for the prospects of achieving sustainable and resilient food systems. This paper is an attempt at addressing this gap by examining changing biophysical and social factors, with specific consideration of vulnerable groups, across four case studies (Ghana, Malawi, Norway and Spain). In each case, future climate change scenarios and associated biophysical limits are mapped onto four key social factors that drive vulnerability and mediate adaptation, namely, scale, history, power and politics, and social differentiation. We then consider what the interaction between biophysical limits and socio-political dynamics means for the options for and limits to future adaptation, and how climate may interact with, and reshape, socio-political elements. We find that biophysical limits and socio-political factors do not operate in isolation, but interact, with dynamic relationships determining the 'space' or set of options for sustainable adaptation. By connecting the perspectives of biophysical and social factors, the study illuminates the risks of unanticipated outcomes that result from the disregard of local contexts in the implementation of adaptation measures. We conclude that a framework focusing on the space for sustainable adaptation conditioned by biophysical and social factors, and their interactions, can help provide evidence on what does and does not constitute sustainable adaptation, and help to counter unhelpful narratives of climate change as a sole or dominant cause of challenges in food systems.

Peripheral-to-central ratio of Guttae: validity and reliability of an objective method to characterize severity of Fuchs endothelial corneal dystrophy.

PURPOSE: Common methods of measuring severity of Fuchs endothelial corneal dystrophy (FECD) are limited in objectivity, reliability, or start with a variable baseline that prevents distinguishing healthy from affected eyes. The aim of this study was to describe a method of grading FECD that overcomes these limitations. METHODS: Fifteen patients with Fuchs endothelial corneal dystrophy were included in the study. Guttae were imaged with a slit lamp beam 8 mm tall; the bottom 4 mm half of each image was divided into two equally-sized sections. Guttae were counted by four independent graders blinded to disease severity scores. The peripheral:central guttae ratio was compared to modified Krachmer clinical severity scores. The peripheral:central guttae ratio was compared between mild (severity 0.5-3) versus moderate-to-severe (severity 4-5) disease. Receiver operating characteristics defined optimal ratio cutoffs for mild versus moderate-to-severe disease. RESULTS: Increased peripheral guttae and peripheral:central guttae ratio correlated with Krachmer severity (p = 0.021 and p = 0.009, respectively). The difference between mild and moderate-to-severe cases for the peripheral:central guttae ratio was significant (p < 0.001). Inter-rater reliability of total guttae count was high (coefficient = 0.82, p < 0.001). A peripheral:central guttae ratio of 0.16 was the ideal cut-off point (area under the curve = 0.79, sensitivity = 0.78, and specificity = 0.80). CONCLUSION: In this pilot study, the peripheral:central ratio of guttae correlates with subjective clinical severity of Fuchs dystrophy. It starts at a common baseline, has good inter-rater reliability, does not require dilation, and can be conducted with a smartphone and slit-lamp.

Bilateral EK Rejection After COVID-19 Vaccine.

ABSTRACT: Owing to its rapid development, short-term and long-term effects of the COVID-19 vaccine are still not well understood. This case report highlights bilateral corneal endothelial graft rejection after administration of the Pfizer COVID-19 vaccine. A 73-year-old woman with bilateral Descemet stripping endothelial keratoplasty presented with bilateral decreased visual acuity, ocular pain, and photophobia after her second dose of the Pfizer-BioNTech COVID-19 vaccine. Two weeks after vaccine administration, the uncorrected visual acuity was 20/70 and 20/40. Central corneal thickness as measured by ultrasound was 809 and 825 µm and by Scheimfplug imaging was 788 and 751 µm at the pupil center. Slit-lamp biomicroscopy revealed quiet conjunctiva and sclera but was significant for thickened corneas with Descemet folds in both eyes. The patient was instructed to use prednisolone acetate 1% every 1 to 2 hours with Muro ointment at bedtime.

Testing a Popular Smartphone Application for Colour Vision Assessment in Healthy Volunteer Subjects.

We aimed to compare the Ishihara pseudoisochromatic colour vision test with a colour vision test from a popular smartphone application (EyeHandBook [EHB]) using digital image processing to simulate colour vision deficiencies. Three digital versions of the Ishihara and EHB slides were created: full colour; 32 bit- greyscale (removing all colour information); and blue channel (to simulate red-green colour vision deficiencies). Twenty healthy volunteers were shown each colour-edited plate. The answers they reported were compared with what would be expected for that colour-simulation scenario based on the answer key provided in the Ishihara booklet ("expected" answer). There were nine plates that had comparable patterns between the EHB and Ishihara test. We found no significant difference in the overall proportion of "expected" answers for the full colour (p = .35), 32 bit-greyscale (p = .39) and blue channel (p = .22) conditions. There were significant differences between the proportion of "expected" answers among six individual colour- edited plates (p < .05 for each). Colour vision assessment from the EHB is distinct from comparable Ishihara plates. Clinical scenarios that require serial assessment of colour vision may benefit from using the same modality consistently rather than exchanging between the two tests with the assumption of equivalence. Refinement of digital colour editing techniques beyond 32-bit greyscale and RGB channel splitting is necessary in order to accurately simulate colour vision deficiency.

Synthesis and Characterization of Zwitterionic Polymer Brush Functionalized Hydrogels with Ionic Responsive Coefficient of Friction.

Freeze-thaw poly(vinyl alcohol) hydrogels (PVA-H) offer great potential for several biomedical applications due to their biomimetic mechanical properties and biocompatibility. Despite these advantages, the use of PVA-H for load bearing applications has been limited due to poor performance in boundary lubrication compared to natural tissue such as articular cartilage. Recently, zwitterionic polymer brushes have been shown to act as effective boundary lubricants on rigid substrates; however, to the best of our knowledge, the synergistic effects of zwitterionic brushes coupled with the biomimetic fluid load support exhibited by hydrogels have not been reported. We report here on our investigation involving the synthesis and characterization of two unique types of polymer brush functionalized PVA hydrogels. The zwitterionic polymers that were compared contained either [2-(methacryloyloxy)ethyl]dimethyl-3-sulfopropylammonium hydroxide, PMEDSAH, or 2-methacryloyloxyethylphosphorylcholine, PMPC, repeating units. Both hydrogels coated with zwitterionic polymers were found to be cytocompatible. We report further on micrometer-scale surface properties via water contact angle goniometry, surface roughness measurements, and scanning electron microscopy. Finally, the impact of brush functionalization on the mechanics of the tribologically enhanced gels is reported with comparison to natural articular cartilage within the context of Hertzian contact theory.

Periocular infantile hemangiomas: Characteristics, ocular sequelae, and outcomes.

OBJECTIVES: To identify clinical factors associated with complications of periocular infantile hemangioma (IH) and monitor improvement in complication rates post-treatment. METHODS: Retrospective cohort study. Eighty-nine patients diagnosed with periocular IH at a pediatric dermatology clinic of a tertiary care center between 2001 and 2013 were included with parental approval. Parents were interviewed by telephone between July and September of 2015, then again in January 2018 to inquire about ophthalmologic follow-up. Electronic medical records were reviewed from January 2001 through January 2018. RESULTS: Sixty percent of patients demonstrated ocular sequelae, including astigmatism (33%), visual axis obstruction (29%), nasolacrimal duct obstruction (7%), ptosis (4%), amblyopia (3%), and strabismus (1%). Compared with superficial IH, deep and mixed IH had higher odds, 3.4 (P = 0.025) and 3.8 (P = 0.034), respectively, of developing ocular sequelae. All patients with astigmatism prior to involution of IH received systemic therapy, with a significant post-treatment decrease in the proportion of patients with astigmatism (40% to 18%, P = 0.027). Three-quarters of patients experienced complete IH involution by time of enrollment in kindergarten. Fifty-one (57.3%) patients received formal ophthalmologic evaluation confirmed through chart review or phone interview, with average follow-up duration of 51.2 months (range: 1.9, 99.3). CONCLUSION: Deep and mixed IH were more likely to demonstrate ocular complications than superficial IH. Rate of astigmatism decreased with systemic therapy. Our study suggests that patients with periocular IH have a lower rate of amblyopia now compared with the prepropranolol era and emphasizes the importance of early treatment of periocular IH to prevent permanent visual sequelae.

Prognostic factors and survival for malignant conjunctival melanoma and squamous cell carcinoma over four decades.

PURPOSE: To determine the epidemiology and survival of primary conjunctival malignant neoplasms. METHODS: Retrospective analysis of primary malignant conjunctival neoplasms using Surveillance, Epidemiology, and End Results database from 1973 to 2012. RESULTS: Of 1661 cases, the most common neoplasms are squamous cell carcinoma (SCC) at 54.8% and melanoma at 38.8%. Mean diagnostic age for melanoma was 62.1 compared to 65.5 years for SCC (p = 0.002). 52.2% of melanoma are male versus 77.4% of SCC (p < 0.001). For SCC only age (HR: 1.09, 95% CI:1.04-1.14) is a predictor of survival. For melanoma, age (HR: 1.07, 95% CI: 1.05-1.10), male sex (HR: 2.04, 95% CI: 1.16-3.60), T4 tumors (HR: 3.38, 95% CI: 1.17-9.80) and N1 status (HR: 8.69, 95% CI: 2.75-27.42) are all survival predictors. The 5 and 10-year overall survival (OS) estimates are not significantly different between SCC and melanoma, with 70% and 50% respectively for SCC, and 71% and 50% respectively for melanoma. Median survival time is worse for blacks (52 months) compared to whites (118 months) and Asians/Native Americans/Pacific Islanders (145 months), however race was not found to be a significant prognostic factor in multivariate analysis. Five-year survival are similar between decades 1973-1982 (66.2%), 1983-1992 (69.2%), 1993-2002 (71.3%) and 2003-2012 (70.2%). CONCLUSION: Age at diagnosis is a determinant of survival for both conjunctival SCC and melanoma. Male sex, T4 and N1 staging are also important prognostic factors for melanoma. With respect to overall survival, SCC and melanoma did not differ significantly.

Endothelial keratoplasty for corneal endothelial dystrophy in a dog.

OBJECTIVE: To assess the efficacy of an endothelial keratoplasty procedure at defined intervals to 1 year postoperatively for the treatment of corneal endothelial dystrophy (CED) in a canine patient. PROCEDURE: A dog diagnosed with CED with progressive corneal edema underwent an endothelial keratoplasty. The patient was examined pre- and postoperatively with slit lamp biomicroscopy and ultrasonic pachymetry. RESULTS: Mean central corneal thickness (CCT) measured with pachymetry was >1400 µm preoperatively and decreased postoperatively to 725 µm. The transplanted donor tissue became transparent 2 weeks postoperatively and incorporated with the recipient cornea. The graft remained transparent throughout the duration of the postoperative period evaluated in this study (2 weeks postoperatively to 1 year). The canine patient was comfortable pre- and postoperatively. CONCLUSIONS: Endothelial keratoplasty is a potential therapeutic option for canine cases with progressive corneal thickening due to CED. As this is a single case study, further investigation into the use of endothelial keratoplasty to treat CED is warranted. Moreover, canine patients with CED might serve as a surgical model for human patients with Fuchs' Endothelial Corneal Dystrophy.

Comparison of a Smartphone Application with Ishihara Pseudoisochromatic Plate for Testing Colour Vision.

The Eye Handbook (EHB) is the most frequently downloaded smartphone application with diagnostic tools for eye-care providers. However, limited data exists validating the EHB test to gold standard colour vision testing. EHB and Ishihara colour vision tests were evaluated and compared under simulated colour vision loss through use of image processing software. Images of both tests were processed through ImageJ to 32 bit-grey scale and blue channel under split RBG channel to model total colour vision loss and red-green (R-G) deficiency, respectively. Two colour plates differentiated R-G deficiency from total colour blindness in EHB compared with eight Ishihara plates. Without colour information, correct numerals were identified in 3.5/15 EHB plates converted to 32-bit greyscale, versus 1/16 in Ishihara. We conclude EHB may underestimate colour vision loss severity in persons with normal contrast sensitivity compared to Ishihara. Eye-care providers need to be aware of the potential inconsistency compared to standardised methods, including limitations in differentiating patients with R-G colour deficiencies from total colour blindness.

Effects of Contrast Sensitivity on Colour Vision Testing.

This study analyses how contrast sensitivity loss affects colour vision (CV) testing. Eleven participants were scored while cycling through randomly arranged pictures of CV tests with varying levels of contrast changes applied. Hardy-Rand-Rittler (HRR) scores declined significantly at each successive decrease in contrast level after the highest setting (p < 0.004). HRR scores were also lower than those for Ishihara and Farnsworth D-15 tests at two contrast settings (p < 0.01). Contrast changes had the greatest impact on HRR scores, indicating that this test may not be an accurate reflection of CV in patients with contrast sensitivity loss.

Bringing inorganic chemistry to life with inspiration from R. J. P. Williams.

Our appreciation of the scholarly ideas and thinking of Bob Williams is illustrated here by a few of the areas in which he inspired us. His journey to bring inorganic chemistry to life began with an early interest in analytical chemistry, rationalising the relative stabilities of metal coordination complexes (The Irving-Williams Series), and elucidating the organometallic redox chemistry of vitamin B12. He (and Vallee) recognised that metal ions are in energised (entatic) states in proteins and enzymes, which themselves are dynamic structures of rods and springs. He played a key role in helping Rosenberg to pave the road toward the clinic for the anticancer drug cisplatin. He believed that evolution is not just dependent on DNA, but also on the metallome. Organisms and the environment are one system: does DNA code directly for all the essential elements of life?

Notes from the Field: Meningococcal Disease in an International Traveler on Eculizumab Therapy - United States, 2015.

On June 2, 2015, CDC was notified that a male airline passenger, aged 41 years, with a fever of 105.4°F, headache, nausea, photophobia, diarrhea, and vomiting, which began approximately 3 hours after departure, was arriving to San Francisco, California, on a flight from Frankfurt, Germany. His symptoms reportedly started with neck stiffness 1 day earlier. Upon arrival, the patient was immediately transported to a local hospital, where he was in septic shock, which was followed by multisystem organ failure. Cerebrospinal fluid, obtained approximately 12 hours after initiation of treatment, was Gram stain- and culture-negative. Blood cultures, which were drawn before antibiotic treatment, were positive for Neisseria meningitides of indeterminate serogroup. A review of the patient's medical records revealed a history of paroxysmal nocturnal hemoglobinuria and current biweekly eculizumab (Soliris) therapy.

First Human Case of Fungal Keratitis Caused by a Putatively Novel Species of Lophotrichus.

We report an aggressive fungal keratitis caused by a putatively novel species of Lophotrichus in a patient with traumatic injury to the cornea from a dog paw. The organism was isolated from the patient's necrotic cornea, which perforated despite coverage with hourly fortified broad-spectrum topical antibiotic therapy. This report represents the first case of human infection caused by this species.

Isolated adult lymphadenopathy: a rare presentation of Langerhans cell histiocytosis.

INTRO: Langerhans cell histiocytosis (LCH) is a rare disease involving the proliferation of histiocytes in one or more organ systems. The presentation of LCH is more common in the pediatric population and rarely occurs within the adult population. Isolated lymph node involvement is an extremely rare presentation of the disease. The authors present a case of isolated lymph node LCH in an otherwise healthy adult female and discuss management strategies for these unusual findings. METHODS: A case report of a patient at a tertiary care facility in June 2014 is discussed. RESULTS/DISCUSSION: The diagnosis, clinical course, and management strategies for isolated adult LCH are discussed and reviewed. CONCLUSION: Langerhans cell histiocytosis rarely presents with isolated lymph node involvement in adults. Management and surveillance algorithms are discussed in this unusual case of seemingly benign lymphadenopathy.

Robotic pilot study for analysing spasticity: clinical data versus healthy controls.

BACKGROUND: Spasticity is a motor disorder that causes significant disability and impairs function. There are no definitive parameters that assess spasticity and there is no universally accepted definition. Spasticity evaluation is important in determining stages of recovery. It can determine treatment effectiveness as well as how treatment should proceed. This paper presents a novel cross sectional robotic pilot study for the primary purpose of assessment. The system collects force and position data to quantify spasticity through similar motions of the Modified Ashworth Scale (MAS) assessment in the Sagittal plane. Validity of the system is determined based on its ability to measure velocity dependent resistance. METHODS: Forty individuals with Acquired Brain Injury (ABI) and 45 healthy individuals participated in a robotic pilot study. A linear regression model was applied to determine the effect an ABI has on force data obtained through the robotic system in an effort to validate it. Parameters from the model were compared for both groups. Two techniques were performed in an attempt to classify between healthy and patients. Dynamic Time Warping (DTW) with k-nearest neighbour (KNN) classification is compared to a time-series algorithm using position and force data in a linear discriminant analysis (LDA). RESULTS: The system is capable of detecting a velocity dependent resistance (p<0.05). Differences were found between healthy individuals and those with MAS 0 who are considered to be healthy. DTW with KNN is shown to improve classification between healthy and patients by approximately 20 % compared to that of an LDA. CONCLUSIONS: Quantitative methods of spasticity evaluation demonstrate that differences can be observed between healthy individuals and those with MAS of 0 who are often clinically considered to be healthy. Exploiting the time-series nature of the collected data demonstrates that position and force together are an accurate predictor of patient health.

Fluorescein-conjugated hyaluronic acid enables visualization of retained ophthalmic viscosurgical device in anterior chamber.

PURPOSE: To develop and assess the utility of an ophthalmic viscosurgical device (OVD) manufactured with fluorescein-conjugated hyaluronic acid (conjHA). SETTING: Department of Biomedical Engineering and the Wilmer Eye Institute, Johns Hopkins University and School of Medicine, Baltimore, Maryland. DESIGN: Laboratory study. METHODS: ConjHA and unconjugated HA (unconjHA) at varied ratios were used to produce OVD (conjOVD) with varied fluorescence intensity. The conjHA:unconjHA ratio was optimized to maximize clarity under white light and fluorescence intensity under cobalt blue light (CBL), allowing for conditional visualization. The effect of conjugation on conjOVD viscosity was assessed by rotational rheometry. Intraocular lenses (IOLs) were immersed in conjOVD for 4 hours to assess staining of IOLs. A proof-of-concept study was performed in ex vivo porcine eyes. After injection and visualization, the OVDs were removed from the eyes by irrigation/aspiration (I/A). RESULTS: 0.5 mg/mL of conjHA (degree of substitution = 0.005) enabled robust fluorescence of conjOVD under CBL. Fluorescein conjugation did not significantly affect conjOVD viscosity ( P > .05 for mean difference in viscosity at all shear rates tested). No staining of IOLs was appreciated. ConjOVD was visualized under CBL when injected ex vivo and maintained clarity of the anterior chamber under white light. Importantly, conjHA enabled delineation of retained OVD after I/A. CONCLUSIONS: Use of OVD composed of fluorescein-conjugated HA is a feasible method to enable conditional visualization of OVD intraoperatively without nonspecific staining of ocular structures. Further development of this technology may enable accelerated OVD removal in ocular surgery or decreased OVD retention postoperatively.

Tandem Mass Tag LC-MS/MS of Aqueous Humor From Individuals With Type 2 Diabetes Without Retinopathy Reveals Early Dysregulation of Synaptic Proteins.

Purpose: An early neurodegenerative component of diabetic retinal disease (DRD) that precedes the vascular findings of clinically diagnosed diabetic retinopathy (DR) is increasingly being recognized. However, the relevant molecular mechanisms and biomarkers for early DRD are poorly defined. The purpose of this study was to uncover novel potential mediators of early diabetic retinal neuronal dysfunction through analysis of the aqueous fluid proteome in preclinical DR. Methods: Aqueous fluid was collected from subjects with type 2 diabetes mellitus (DM) but no clinical DR and from nondiabetic controls undergoing routine cataract surgery. Preoperative spectral-domain optical coherence tomography of the macula was obtained. Tandem mass tag LC-MS/MS was performed to identify proteins differentially present in diabetic and control aqueous fluid, and proteins with >50% change and P < 0.05 were considered significant. Selected results were validated with western blot of human aqueous fluid samples. Results: We identified decreased levels of proteins implicated in neuronal synapse formation and increased levels of inflammatory proteins in the aqueous fluid from patients with type 2 DM but no DR compared with controls. Of the differentially present synaptic proteins that we identified and confirmed with western blot, the majority have not previously been linked with DRD. Conclusions: The proteomic profile of aqueous fluid from individuals with type 2 DM but no DR suggests that retinal neuronal dysfunction and inflammation represent very early events in the pathophysiology of DRD. These findings support the concept that diabetic retinal neurodegeneration precedes vascular pathology and reveal novel potential mediators and/or biomarkers warranting further investigation.

Effect of Anterior Chamber Air on Central Corneal Thickness in Human Donor Eyes.

PURPOSE: The purpose of this study was to describe the effects of intracameral air on corneal edema. METHODS: A laboratory investigation was performed on human donor corneas. Baseline pachymetry measurements through anterior segment optical coherence tomography and endothelial cell density were obtained for all corneas. Each pair of corneas was separated and randomly assigned to undergo air injection or Optisol-GS into a BIONIKO artificial anterior chamber for 5 minutes at physiologic intraocular pressure confirmed by digital palpation. Photographs were obtained immediately on connection of the cornea to the artificial anterior chamber and on completion of the 5 minutes of treatment, with anterior chamber air being exchanged for Optisol-GS. Pretreatment and posttreatment photographs were obtained. Immediately after treatment, pachymetry was again obtained on all corneas. Pachymetry data underwent statistical analysis. RESULTS: Corneal pachymetry improved from 690.5 ± 126.6 to 576.1 ± 87.2 µm, yielding a 114.4 ± 50.4 µm improvement of pachymetry in the group with air injected into the anterior chamber. This was a significant improvement of pachymetry when compared with the group with Optisol-GS injected into the anterior chamber, which showed an improvement from 662.3 ± 126.5 to 613.5 ± 108.0 µm, yielding an improvement of 48.8 ± 34.3 µm. CONCLUSIONS: Injection of air into the anterior chamber leads to a significant decrease in corneal pachymetry. We thereby propose that injecting air intracamerally is an effective intraoperative intervention when visualization is negatively affected by corneal edema.