Survey of the Faculty Status of Optometrists at Academic Medical Centers in the United States.

SIGNIFICANCE: This is the first study of the prevalence and faculty status of optometrists practicing at academic medical centers in the United States. PURPOSE: This study aimed to quantify the number of optometrists at academic medical centers, along with faculty rank and post-doctoral training programs. METHODS: The official Web sites of academic medical centers and schools of medicine in the United States were examined during the 2021 to 2022 academic year to identify departments of ophthalmology and collect faculty profiles of employed optometrists. Institutional data were cross-referenced and analyzed by geographic distribution. Data were gathered from the Association of Schools and Colleges of Optometry and Accreditation Council on Optometry Education to identify post-graduate training programs in optometry. RESULTS: A total of 192 academic medical centers were identified, of which 121 (63.02%) had a residency or fellowship program in ophthalmology and/or optometry. One hundred twenty-five (65.10%) of these institutions had at least one staff optometrist. Seven hundred eighteen optometrists were found at these institutions, representing 1.83% of the 39,205 practicing optometrists estimated in the United States. Of the 718 optometrists, 369 (51.39%) held an academic appointment at a medical school. The most common academic rank was assistant professor (184 [25.63%]), followed by instructor (138 [19.22%]), associate professor (34 [4.74%]), and full professor (13 [1.81%]). The distribution of academic rank was similar across all regions but varied between institutions as to whether all, some, or none of the optometric faculty were appointed by a medical school. Of 296 optometry residency programs in the United States, 21 (7.09%) were at an academic medical center. Of 15 optometric fellowship programs in the United States, 3 (20%) were at an academic medical center. Of the 192 institutions in this study, 22 (11.46%) had a post-doctoral optometric training program. CONCLUSIONS: This study shows the distribution of academic rank and post-doctoral training programs for optometrists at academic medical centers.

The Economic Burden of Adults with Major Depressive Disorder in the United States (2019).

INTRODUCTION: Previous societal burden estimations for major depressive disorder (MDD) often fail to account for several hidden cost components. This study provides a comprehensive evaluation of societal costs for adults with MDD in the United States (USA) in 2019. The potential impact of a more effective, rapid-acting MDD therapy vs standard of care on the economic burden of MDD was estimated to illustrate the utility of such a framework in evaluating new interventions. METHODS: This study used a prevalence-based human capital approach. Incremental costs (2019 US dollars) per individual with MDD were derived from national survey inputs and published literature and included incremental healthcare costs and indirect costs. For each cost component, the societal costs were extrapolated by multiplying the per-patient costs by the number of individuals with MDD. The impact of a more effective, rapid-acting novel therapy on the economic burden of MDD was then simulated on the basis of these inputs. RESULTS: In 2019, the number of adults with MDD in the USA was estimated at 19.8 million (62.7% female; 32.9% severe MDD), and the incremental societal economic burden of MDD was estimated at $333.7 billion ($382.4 billion in 2023 US dollars), or $16,854 per adult with MDD. The primary cost drivers were healthcare costs ($127.3 billion; 38.1%), household-related costs ($80.1 billion; 24.0%), presenteeism ($43.3 billion; 13.0%), and absenteeism ($38.4 billion; 11.5%). In the simulated scenario, a hypothetical novel therapy with a 50.0% early response rate was associated with a 7.7% reduction in the economic burden of MDD relative to standard of care over 12 months. CONCLUSIONS: The economic burden of MDD is substantial and extends beyond healthcare costs, underscoring the impact of MDD across multiple aspects of life. Such a broad societal perspective should be considered in assessing the impact of the advent of effective, rapid-acting MDD therapies.

Differentiating Between Contact Lens Warpage and Keratoconus Using OCT Maps of Corneal Mean Curvature and Epithelial Thickness.

PURPOSE: To formulate an Epithelial Modulation index to differentiate between eyes with contact lens warpage and keratoconus. METHODS: Normal eyes and eyes with either contact lens warpage or keratoconus were scanned by a Fourier-domain optical coherence tomography (OCT) system. Maps of epithelial thickness and anterior surface mean curvature were generated and converted to deviation maps by subtracting the average maps from a healthy population. The Epithelial Modulation index was defined as the covariance between the two types of deviation maps. A logistic regression model was used to classify eyes as non-keratoconus (normal or warp-age) or keratoconus (manifest, subclinical, or forme fruste). RESULTS: The average Epithelial Modulation index value for normal eyes was -0.6 ± 1.0 µm/m. Eyes with keratoconus were characterized by coincident high anterior surface mean curvature and low epithelial thickness, resulting in a high Epithelial Modulation index (manifest: 103.0 ± 82.9 µm/m, subclinical: 37.0 ± 23.0 µm/m, forme fruste: 7.3 ± 13.2 µm/m). The Epithelial Modulation index was closer to normal for eyes with warpage (-1.9 ± 4.0 µm/m). The classification accuracy of the Epithelial Modulation index during five-fold cross-validation of the logistic regression model was 100 ± 0% for normal eyes and 99.0 ± 2.0% for eyes with warpage. The accuracy was 100 ± 0%, 100 ± 0%, and 53.1 ± 1.5% for the manifest, subclinical, and forme fruste keratoconus groups, respectively. CONCLUSIONS: The Epithelial Modulation index is useful in distinguishing eyes with secondary epithelial modulation (keratoconus) from those with primary epithelial deformation (contact lens-related warpage). [J Refract Surg. 2022;38(2):112-119.].

Distinguishing between contact lens warpage and ectasia: Usefulness of optical coherence tomography epithelial thickness mapping.

PURPOSE: To distinguish between corneal ectasia and contact lens-related warpage by characteristic patterns on corneal topography and optical coherence tomography (OCT) epithelial thickness maps. SETTING: Casey Eye Institute, Portland, Oregon, USA. DESIGN: Prospective and retrospective case series. METHODS: Axial and mean power maps were obtained on corneal topography systems. Epithelial thickness maps were generated using RTVue OCT. A sector divider was applied to all maps. The locations of the minimum epithelial thickness, maximum epithelial thickness, maximum axial power, and maximum mean power were determined based on sector averages. Agreement was defined as the extremums occurring in the same or adjacent sectors. RESULTS: Twenty-one eyes with keratoconus, 6 eyes with forme fruste keratoconus (better eye of asymmetric keratoconus), and 15 eyes with contact lens-related warpage were identified. The keratoconus and forme fruste keratoconus eyes had coincident topographic steepening with epithelial thinning. The locations of minimum epithelial thickness and maximum axial power agreed in 90% of the keratoconic eyes, while the minimum epithelial thickness and maximum mean power agreed in 95% of them. Conversely, the warpage eyes had coincident topographic steepening with epithelial thickening and normal pachymetry maps. The locations of maximum epithelial thickness and maximum axial power agreed in 93% of the warpage eyes, while the maximum epithelial thickness and maximum mean power agreed in all warpage eyes. CONCLUSION: Results show that epithelial thickness maps and corneal topographic maps are powerful synergistic tools in evaluating eyes with abnormal topography and can help differentiate between keratoconus and nonectatic conditions.

Differentiating Keratoconus and Corneal Warpage by Analyzing Focal Change Patterns in Corneal Topography, Pachymetry, and Epithelial Thickness Maps.

PURPOSE: To differentiate between keratoconus and contact lens-related corneal warpage by combining focal change patterns in anterior corneal topography, pachymetry, and epithelial thickness maps. METHODS: Pachymetry and epithelial thickness maps of normal, keratoconus, and warpage, and forme fruste keratoconus (FFK) eyes were obtained from a Fourier-domain optical coherence tomography (OCT). Epithelial pattern standard deviation (PSD) was calculated and combined with two novel indices, the Warpage Index and the Anterior Ectasia Index, to differentiate between normal, keratoconus, and warpage eyes. The values of the three parameters were compared between groups. RESULTS: The study included 22 normal, 31 keratoconic, 11 warpage, and 8 FFK eyes. The epithelial PSD was normal (< 0.041) for 100% normal eyes and abnormal (> 0.041) for 100% of keratoconic eyes, 81.8% of warpage eyes, and 87.5% of FFK eyes. The Anterior Ectasia Index of normal eyes (1.66 ± 0.74) was significantly lower than that for the keratoconus eyes (17.5 ± 7.17), the warpage eyes (2.98 ± 1.69), and the FFK eyes (6.95 ± 5.86). The Warpage Index was positive in all warpage eyes and negative for all keratoconic and FFK eyes except three wearing rigid gas-permeable contact lens. CONCLUSIONS: The epithelial PSD can distinguish normal from keratoconus or warpage, but does not distinguish between these two conditions. The Anterior Ectasia Index is abnormal in keratoconus but not warpage. The Warpage Index is positive for warpage and negative for keratoconus, except in cases where keratoconus and warpage coexist. Together, the three parameters are strong tripartite discriminators of normal, keratoconus, and warpage.

Quantitative and conformational characterization of lysozyme deposited on balafilcon and etafilcon contact lens materials.

PURPOSE: To determine whether differences in lysozyme deposition and/or activity exist on worn etafilcon and balafilcon contact lenses following care with a polyquaternium-based system (PQ) or a polyhexanide-based system (PHMB). METHODS: Following acid-based deposit extraction, lysozyme concentration was determined via Western blotting and lysozyme activity was determined by a micrococcyl assay. RESULTS: Lysozyme deposition on etafilcon lenses was greater following disinfection with the PHMB-based system (1551 +/- 371 micro g/lens vs 935 +/- 271 micro g/lens; p < 0.001). Deposition on balafilcon lenses was not influenced by the care regimen (10 +/- 3.5 micro g/lens vs 10 +/- 5 micro g/lens; p = 0.89). For both materials, the percentage of denatured lysozyme was greater when they were exposed to the PHMB-based system (28 vs 21%; p = 0.05 (etafilcon) and 57 vs 40%; p = 0.04 (balafilcon)). CONCLUSIONS: The quantity and conformation of lysozyme deposited on hydrogel contact lens materials is significantly influenced by both lens material and care regimen.

Lysozyme and lipid deposition on silicone hydrogel contact lens materials.

PURPOSE: We sought to determine whether there were differences in lysozyme (quantity and conformation) and lipid deposition on in vivo worn conventional (etafilcon) and silicone hydrogel (balafilcon and lotrafilcon) contact lenses. METHODS: After extraction, lysozyme concentration in each extract was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. Lysozyme activity was determined by the rate of lysis of Micrococcis lysodeikticus cells. Lipid deposition was determined by high-performance liquid chromatography. RESULTS: Lysozyme deposition on etafilcon lenses was significantly greater than that measured on silicone hydrogel (SH) lenses (985 microg per lens versus 10 and 3 microg per lens for balafilcon and lotrafilcon materials, respectively; P<0.001). The degree to which lysozyme was denatured was influenced by the lens material, with the lowest degree of denaturation (22%) seen on the conventional lens material, as compared with 50% for balafilcon and 80% for lotrafilcon (P<0.001). Lipid deposition was greatest on the SH materials, with up to 600 microg per lens of certain lipid classes being deposited on balafilcon, as compared with 20 microg per lens on etafilcon (P<0.001). CONCLUSION: The quantity and conformation of lysozyme and the quantity of lipid deposited on hydrogel contact lenses is significantly influenced by the composition of the lens material. SH contact lens materials deposit low levels of lysozyme and high levels of lipid deposition compared with ionic contact lens materials. Although SH materials deposit only small amounts of lysozyme, the degree of lysozyme denaturation that occurs is higher relative to that seen on ionic lens materials.