Association of optical cataract indices with cataract severity and visual function.

PURPOSE: The purpose of this study is to determine the correlation between subjective and optical measurements used during cataract evaluation, including the iTrace Dysfunctional Lens Index (DLI), the HD Analyzer Objective Scatter Index (OSI), Lens Opacities Classification System III (LOCS III), Visual Function-14 Questionnaire (VF-14), and the Pelli-Robson Contrast Sensitivity Chart (PRCSC). METHODS: Seventy eyes from 70 patients were enrolled, including all stages of age-related nuclear cataracts. The LOCS III-NO with a cutoff of 3.2 was chosen to divide the population into two groups. Eyes with corneal or retinal pathology were excluded. All patients were evaluated with the iTrace's DLI, HD Analyzer's OSI, LOCS III, VF-14, and the PRCSC during each follow-up visit. Correlation analyses were performed using Stata software, version 14.0, StataCorp. RESULTS: The LOCS III-NO, DLI, OSI, and VF-14 questionnaire each correlated moderately with the BCVA with a Spearman rho value of 0.37, - 0.45, 0.40, and - 0.35, respectively. The DLI correlated moderately with LOCS III-NO with a rho value of - 0.37 and with the VF-14 questionnaire with a rho value of 0.35. The OSI correlated with both the contrast sensitivity and DLI with a rho value of - 0.35 and - 0.55, respectively. CONCLUSIONS: The DLI correlated with cataract symptoms (measured by the VF-14 questionnaire) in addition to BCVA. The OSI correlated moderately with contrast sensitivity and BCVA. The highest correlation was between DLI and OSI.

Repeatability of central corneal thickness measurements of donor corneas in preservation chamber using Fourier-domain anterior segment optical coherence tomography.

To evaluate the repeatability of central corneal thickness (CCT) measurements in donor corneas using optical coherence tomography (OCT, RTVue-Optovue, Inc., Fremont, CA). Consecutive corneas were measured by a single observer using the RTVue. All corneas were preserved in the Transend chamber and Life4 °C media (Numedis, Inc., Isanti, MN/USA) and stored at 4 °C. The repeatability was evaluated using a pooled within-subject standard deviation (SD), coefficient of variation (CoV), and intraclass correlation coefficient (ICC). To investigate inter-observer repeatability, a second observer independently measured the CCT for each image scan. CCT was measured in 32 eyes from 18 donors. Measurements were independently repeated by a second observer. The corneas had a mean CCT of 490.99 µm ± 65.95 (381-642) as measured by Observer 1. For observer 1, the SD value for the CCT was 2.94 µm, the CoV value was 0.597%, and the ICC value was 0.998 (95% CI 0.996, 0.999). For observer 2, the SD value was 5.91 µm, the CoV value was 1.21%, and the ICC value was 0.992 (95% CI 0.985, 0.996). The Kappa statistic 21.88% with a p value < 0.001. The Bland-Altman plot shows that the average CCT measurements between the two observers were within 20 µm of each other. The CCT measurements of donor corneas in the preservation chamber using Fourier domain OCT is highly repeatable.

Peripheral retinal neovascularization in a patient with obstructive sleep apnea.

Purpose: To describe a case of peripheral retinal neovascularization and its possible etiological connection to comorbid obstructive sleep apnea. Observations: In this case report we describe a diabetic patient with obstructive sleep apnea who presented with bilateral peripheral retinal neovascularization but in the absence of any other evidence of diabetic retinopathy. Aside from confirmed nocturnal hypoxia and reasonably controlled diabetes mellitus, etiological investigation was otherwise unrevealing. Conclusions and Importance: In the absence of typical findings for diabetic retinopathy, nocturnal hypoxia due to obstructive sleep apnea may be a contributing factor in the development of peripheral retinal neovascularization. There may be a role for more vigilant OSA screening in patients with peripheral retinal neovascularization as treatment with positive airway pressure devices may reduce the retinal hypoxic burden.

Association Between E-Cigarette Use and Visual Impairment in the United States.

PURPOSE: To determine whether there is an association between e-cigarette use and visual impairment in the United States adult population. DESIGN: Cross-sectional. METHODS: In this population survey study, we reviewed 1,173,646 adults ≥18 years of age from all 50 United States and 3 U.S. territories with self-reported responses to the Center for Disease Control and Prevention's 2016-2018 Behavioral Risk Factor Surveillance System (BRFSS) annual telephone survey. We reviewed e-cigarette use (current, former, or never), as assessed by the questions: "Have you ever used an e-cigarette or other electronic vaping product, even just one time, in your entire life?" and "Do you now use e-cigarettes or other electronic vaping products every day, some days, or not at all?" The primary outcome measure was visual impairment, defined as a binary outcome "yes" or "no" to the question, "Are you blind or do you have serious difficulty seeing, even when wearing glasses?" RESULTS: After excluding missing data, there were 1,173,646 participants. The adjusted odds ratio of visual impairment in current e-cigarette users compared with never e-cigarette users was 1.34 (95% confidence interval [CI] 1.20-1.48), and in former e-cigarette users was 1.14 (95% CI 1.06-1.22). In the subgroup of 662,033 never users of traditional cigarettes (weighted 59.6% of study population), the adjusted odds ratio of visual impairment in current e-cigarette users compared with never e-cigarette users was 1.96 (95% CI 1.48-2.61) and in former e-cigarette users was 1.02 (95% CI 0.89-1.18). CONCLUSIONS: Current compared with never e-cigarette usage was associated with a higher odds of visual impairment in the BRFSS 2016-2018 population, independent of traditional cigarette use.

Clinical laboratory tests associated with survival in patients with metastatic renal cell carcinoma: A Laboratory Wide Association Study (LWAS).

BACKGROUND: Prognostic models for patients with metastatic renal cell carcinoma (mRCC) include select laboratory values. These models have important limitations, including reliance on a limited array of laboratory tests, and use of dichotomous ("high-low") cutoffs. We applied a Laboratory-Wide Association Study (LWAS) framework to systematically evaluate common clinical laboratory results associated with survival for patients diagnosed with mRCC. METHODS: We used laboratory data for 3,385 patients diagnosed with mRCC from 2002 to 2017. We developed a LWAS framework, to examine the association with 53 common clinical laboratory tests results (641,712 measurements) and overall survival. We employed false-discovery rate to test the association of multiple laboratory tests with survival, and validated these results using 3 separate cohorts to generate a standardized hazard ratio (sHR), reported for a 1 standard deviation unit change in each laboratory test. RESULTS: The LWAS approach confirmed the association of laboratory values currently used in prognostic models with survival, including calcium (HR 1.35, 95%CI 1.24-1.48), leukocyte count (HR 1.40, 95%CI 1.30-1.51), platelet count (HR 1.36, 95%CI 1.27-1.51), and hemoglobin (HR 0.79, 95%CI 0.72-0.86). Use of these tests as continuous variables improved model performance. LWAS also identified acute phase reactants associated with survival not typically included in prognostic models, including serum albumin (HR 0.66, 95%CI 0.61-0.72), ferritin (HR 1.25, 95%CI 1.08-1.45), alkaline phosphatase (HR 1.31, 95%CI 1.23-1.40), and C-reactive protein (HR 1.70, 95%CI 1.14-2.53). CONCLUSIONS: Routinely measured laboratory tests can refine current prognostic models, facilitate comparisons across clinical trial cohorts, and match patients with specific systemic therapies.

Guillain-Barré syndrome in a man presenting with upper extremity monoplegia.

Outside academia, community and rural medical centers often rely on clinical signs and symptoms for early intervention, as means of gathering objective data may be unavailable, or the reliance of biological testing may take too long to return. Continued reporting of atypical presentations is therefore necessary for broadening clinical recognition of such cases.

Anterior Segment Optical Coherence Tomography of Ocular Cystinosis Confirmed by Electron Microscopy.

PURPOSE: To report a case of ocular cystinosis diagnosed by anterior segment optical coherence tomography (AS-OCT) and histopathology. METHODS: A 67-year-old man who presented with eye pain was found to have unilateral corneal crystal deposition. Ocular cystinosis was diagnosed by histopathology, AS-OCT, and lack of renal involvement of the disease. RESULTS: AS-OCT showed hyperreflective densities in the corneal epithelium. The patient underwent superficial keratectomy given irregular astigmatism prior to cataract surgery. Electron microscopy of the corneal scrapings revealed epithelial cells with intracystoplasmic membrane-bound crystals confirming the diagnosis of cystinosis. CONCLUSION: To our knowledge, this is the first reported case of ocular cystinosis involving strictly the epithelial layer of the cornea that has been imaged by AS-OCT.

Astigmatism induced by intraocular lens tilt evaluated via ray tracing.

PURPOSE: To evaluate astigmatism induced by aspheric and toric intraocular lens (IOL) tilt using a ray-tracing model. SETTING: Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. DESIGN: Experimental study. METHODS: Ray-tracing eye models with aspheric IOLs (16.0 diopters [D], 22.0 D, and 28.0 D) and toric IOLs (16.0 D, 22.0 D, and 28.0 D each with toricities of 1.50 D, 3.75 D, and 6.00 D) were used. The IOLs were tilted from 1 to 10 degrees horizontally around a 90-degree vertical meridian. Toric IOLs were aligned at 90 degrees and 180 degrees to correct with-the-rule (WTR) and against-the-rule (ATR) corneal astigmatism, respectively. Astigmatism at the corneal plane induced by IOL tilt was calculated. RESULTS: Induced astigmatism increased with increasing IOL tilt and power. Horizontal tilt around a vertical meridian induced ATR astigmatism. For 5 degrees of tilt, induced astigmatism was 0.08 D, 0.11 D, and 0.14 D for 16.0 D, 22.0 D, and 28.0 D aspheric IOLs, respectively. Ten degrees of IOL tilt produced 0.33 D, 0.44 D, and 0.56 D of induced astigmatism for 16.0 D, 22.0 D, and 28.0 D aspheric IOLs, respectively. Tilting toric IOLs aligned at 90 degrees around a vertical meridian increased the magnitude of induced ATR astigmatism. Tilting toric IOLs aligned at 180 degrees decreased the magnitude of induced WTR astigmatism. CONCLUSIONS: Tilting aspheric IOLs horizontally around a vertical meridian induced ATR astigmatism. Tilting toric IOLs aligned at 90 degrees increased ATR astigmatism, resulting in overcorrection. Tilting toric IOLs aligned at 180 degrees decreased WTR astigmatism, producing undercorrection.