Dynamic contour tonometry vs. non-contact tonometry and their relation with corneal thickness

The purpose of this study is to evaluate the concordance between intraocular pressure (IOP) values obtained with a dynamic contour tonometer (DCT) and a non-contact tonometer (NCT) in healthy patients and to investigate the effect of central corneal thickness (CCT) on IOP readings for each of the two measuring systems. The mean IOP yielded by DCT, NCT and corrected non-contact tonometer (CNCT) was 17.1 mmHg, 15.5 mmHg and 12.2 mmHg, respectively. The average CCT was 563.6 μm and the ocular pulse amplitude (OPA) was 2.8 mmHg. There was a moderate correlation between CCT and CNCT (r = 0.34, p = 0.001), a weak correlation between CCT and DCT (r = 0.03, p = 0.788) and a weak-to-moderate correlation between CCT and NCT (r = 0.27, p = 0.11). The intra-class correlation coefficient (ICC) was 0.59 for the DCT-vs.-NCT comparison and 0.56 for DCT-vs.-CNCT. The mean difference between the two instruments (DCT/NCT) ranged from 1.62 to 4.47 mmHg. We have shown that non-contact tonometer is significantly more affected by the central corneal thickness than the dynamic contour tonometer and therefore these methods are not interchangeable

Repeatability and reproducibility of corneal thickness using SOCT Copernicus HR

Purpose: The aim of this study is to determine the reliability of corneal thickness measurements derived from SOCT Copernicus HR (Fourier domain OCT). Methods: Thirty healthy eyes of 30 subjects were evaluated. One eye of each patient was chosen randomly. Images were obtained of the central (up to 2.0 mm from the corneal apex) and paracentral (2.0 to 4.0 mm) cornea. We assessed corneal thickness (central and paracentral) and epithelium thickness. The intra-observer repeatability data were analysed using the intra-class correlation coefficient (ICC) for a range of 95 per cent within-subject standard deviation (SW) and the within-subject coefficient of variation (CW). The level of agreement by Bland–Altman analysis was also represented for the study of the reproducibility between observers and agreement between methods of measurement (automatic versus manual). Results: The mean value of the central corneal thickness (CCT) was 542.4 ± 30.1 μm (SD). There was a high intra-observer agreement, finding the best result in the central sector with an intra-class correlation coefficient of 0.99, 95 per cent CI (0.989 to 0.997) and the worst, in the minimum corneal thickness, with an intra-class correlation coefficient of 0.672, 95 per cent CI (0.417 to 0.829). Reproducibility between observers was very high. The best result was found in the central sector thickness obtained both manually and automatically with an intra-class correlation coefficient of 0.990 in both cases and the worst result in the maximum corneal thickness with an intra-class correlation coefficient of 0.827. The agreement between measurement methods was also very high with intra-class correlation coefficient greater than 0.91. On the other hand the repeatability and reproducibility for epithelial measurements was poor. Conclusion: Pachymetric mapping with SOCT Copernicus HR was found to be highly repeatable and reproducible. We found that the device lacks an appropriate ergonomic design as proper focusing of the laser beam onto the cornea for anterior segment scanning required that patients were positioned slightly farther away from the machine head-rest than in the setup for retinal imaging

Eye-Related COVID-19: A Bibliometric Analysis of the Scientific Production Indexed in Scopus

This paper analyzes, from a bibliometric viewpoint, those publications that relate COVID-19 and eye indexed in Scopus since the beginning of the pandemic, and it identifies the resulting main research lines. A bibliographic search in the Scopus database was conducted for publications that simultaneously include ocular and visual manifestations and aspects with COVID-19, from 1 January 2020 to 16 March 2021, and the obtained bibliographic information was processed with VOSviewer (v. 1.6.16). A total of 2206 documents were retrieved, and 60% were original articles. The USA published the most studies (24.6%). The retrieved documents had a total of 18,634 citations. The h index of the set of retrieved documents was 58. The Indian Journal of Ophthalmology was the most productive journal, while JAMA Neurology and The Lancet accounted for 20% of citations. Three keyword clusters representing hotspots in this field were identified. Eye-related COVID-19 research is an emerging field with plenty of scientific evidence whose growth is expected to increase as the aspects and manifestations of the disease, its treatment and the effect of vaccination on it become known.This study was supported by grants from the University of Alicante (VIGROB-093FI) Image Analysis, Optical Systems and Vision Group (IMAOS+V)

Prevalence of Computer Vision Syndrome and Its Relationship with Ergonomic and Individual Factors in Presbyopic VDT Workers Using Progressive Addition Lenses

This cross-sectional study estimated computer vision syndrome (CVS) prevalence and analysed its relationship with video display terminal (VDT) exposure, as well as sociodemographic, refractive, environmental, and ergonomic characteristics in 109 presbyopic VDT workers wearing progressive addition lenses (PALs). Usual spectacles were measured with a lens analyser, and subjective refraction was performed by an optometrist. CVS was measured with the CVS-Q©. VDT exposure was collected. Ergonomic evaluations were conducted in a normal working posture looking at the screen. Air temperature and relative humidity were measured (thermohygrometer), and illumination was measured (luxmeter). Descriptive analysis and differences in CVS prevalence, as a function of the explanatory variables, were performed (chi-square test). Multivariate logistic regression was used to identify factors associated with CVS (OR and 95% CI). The mean age was 54.0 ± 4.8 years, and 43.1% were women. The mean hours of VDT use at work was 6.5 ± 1.3 hours/day. The prevalence of CVS was 74.3%. CVS was significantly associated with women (OR 3.40; 95% CI, 1.12–10.33), non-neutral neck posture (OR 3.27; 95% CI, 1.03–10.41) and altered workplace lighting (OR 3.64; 95% CI, 1.22–10.81). Providing training and information to workers regarding the importance of adequate lighting and ergonomic postures during VDT use is advised to decrease CVS and increase workplace quality of life.This study was supported by grants from the Department of Education, Research, Culture and Sports, Valencian Government [GV/2017/187]

Correlation between the dioptric power, astigmatism and surface shape of the anterior and posterior corneal surfaces

A knowledge of the shape of the cornea is of major importance for the planning and monitoring of surgery, and for the correct diagnosis of corneal diseases. Many authors have studied the geometry of the second corneal surface in the central region and it has been stated that there is a high correlation between the central radii of curvature and asphericities of the two corneal surfaces. In this work we extend this study to a larger, central, 6 mm diameter of the cornea. Surface height data, obtained with an Oculus Pentacam from 42 eyes of 21 subjects, were analysed to yield surface power vectors. Corneal heights of both surfaces were also decomposed into low order Zernike polynomials and the correlations between each of the power vectors and low-order Zernike coefficients for the two surfaces were studied. There was not only a strong correlation between spherical powers and Zernike defocus coefficients, but also between the astigmatic components. The correspondence between the astigmatism in both surfaces found here can be of the utmost importance in planning optical surgery, since perfect spherical ablation of the first surface does not assure total correction of corneal astigmatism.This work has been partially supported by the Spanish Ministry of Education and Science through the project nr. FIS2005-05053. Julian Espinosa and Jorge Perez acknowledge financial support from the University of Alicante through the project GRE07-7P. Henryk Kasprzak acknowledges the University of Alicante for its economical support through the project Senior 08/07

Axial Length Changes after Glaucoma Deep Sclerectomy Surgery

Aims: The aim of this study is to determine the longitudinal change in the eye´s axial length (AL), produced by a non-penetrating deep sclerectomy (NPDS). Methods: 22 subjects diagnosed with glaucoma were included in the study (14 at one-month follow-up and 8 at a follow-up of at least one year), who had undergone combined glaucoma and cataract surgery. Compare with a control group of 20 eyes follow up, 14 of them for one month and 6 for one year. The relationship between changes in IOP and AL were retrospectively analyzed. The intraocular pressure (IOP) measurement was taken using contactless tonometry (Topcon CT-80). The AL and depth of the anterior chamber (ACD) was calculated using optical biometry (IOL Master, Carl-Zeiss). An assessment of the refractive status was performed through subjective refraction before and after surgery. Results: An average reduction in IOP of 10.14 ± 6.67mmHg (p0.3, p<0.05) allows us to predict the reduction in AL according to the following formula: Reduction in AL (mm) = 0.065 + (0,006xReduction in IOP)

Estudio de la influencia de aditivos naturales obtenidos de plantas crasas en las propiedades de morteros de adobe

El presente estudio pretende indagar en el comportamiento de varios tipos de gomas vegetales extraídas de plantas de las familias cactácea y agavácea para mejorar la conservación de elementos de adobe. Las plantas seleccionadas fueron: Agave americana L., Agave americana marginata CV, Opuntia ficus índica L. MILL y Austrocylindropuntia subulata (MUHLPFRDT. Backbg). Estas gomas vegetales se han incorporado, a diferentes concentraciones, como aditivo de los ligantes empleados en la elaboración de probetas de adobe, con la finalidad de evaluar las mejoras que estas sustancias orgánicas producen en el comportamiento hídrico y de resistencia mecánica de este tipo de materiales. Paralelamente, se ha estudiado la estabilidad química de estos morteros mediante la determinación de los posibles cambios colorimétricos experimentados por las probetas, cuando éstas se someten a envejecimiento artificial acelerado mediante luz ultravioleta.Medina Lorente, OM.; Carrascosa Moliner, MB.; Domenech Carbo, MT. (2015). Estudio de la influencia de aditivos naturales obtenidos de plantas crasas en las propiedades de morteros de adobe. Arché. (10):170-178. http://hdl.handle.net/10251/852161701781

Tecnologías de la información y comunicación (TIC) en la docencia de las prácticas de laboratorio de Óptica Oftálmica

[ES] La Óptica Oftálmica es una materia que se encuentra dentro del Plan de Estudios del Grado en Óptica y Optometría, dentro del módulo de Óptica se encuentra la materia Óptica Oftálmica. A grandes rasgos, en Óptica Oftálmica se estudia el proceso de formación de imágenes y propiedades de todo tipo de lente oftálmica utilizada en prescripciones optométricas y su proceso de adaptación. Asimismo, trata las técnicas de centrado, adaptación, montaje y manipulación de todo tipo de lentes, de una prescripción optométrica, ayuda visual y gafa de protección. La metodología docente empleada en la asignatura se basa, por un lado, en una parte presencial que incluye las modalidades de clase teórica, prácticas de problemas y clases prácticas, y, por otro lado, una parte no presencial que potencia el autoaprendizaje y que incluye las modalidades de tutorías no presenciales, estudio y trabajo en grupo e individual. Las prácticas de laboratorio se realizan en el laboratorio habilitado para la asignatura. Su contenido aparece agrupado en 8 prácticas individuales de 2 horas de duración por práctica en las que se realiza la medida y montaje de todos los elementos compensadores estudiados en la asignatura. Para cada práctica se prepara un guion donde se indica su objetivo, el material y el procedimiento a seguir. Se propone elaborar videotutoriales con las técnicas de medida de potencias de lentes oftálmicas que proporcionarán al estudiante del Grado de Óptica y Optometría la posibilidad de consultar y visionar en cualquier lugar y momento el manejo del instrumental utilizado en el laboratorio de Óptica Oftálmica. Estas herramientas, además, facilitarán la labor docente del profesorado haciéndola más eficiente al aprovechar los medios tecnológicos que dispone.Espinosa Tomás, J.; Vázquez Ferri, C.; Domenech Amigot, B.; Pérez Rodríguez, J. (2019). Tecnologías de la información y comunicación (TIC) en la docencia de las prácticas de laboratorio de Óptica Oftálmica. En INNODOCT/18. International Conference on Innovation, Documentation and Education. Editorial Universitat Politècnica de València. 585-592. https://doi.org/10.4995/INN2018.2018.8812OCS58559

Reposición de lagunas en cerámica arqueológica. Comparación de la escayola y un producto comercial ante ensayos de envejecimiento acelerado

lo largo de la historia se han venido empleando variados materiales en la elaboración de masillas para la reposición de faltantes en cerámica arqueológica. En la actualidad, la investigación de nuevos materiales ofrece al campo de la restauración innumerables productos, siendo los tradicionales sustituidos. En este trabajo se realiza el estudio comparativo de dos tipos de materiales: uno tradicional como la escayola y un producto comercial en polvo utilizado desde hace dos décadas en sustitución del anterior. Tras preparar distintas probetas, éstas han sido sometidas a condiciones de envejecimiento acelerado (humedad-desecación, luz ultravioleta y atmósfera saturada con SO2, siendo analizadas mediante distintos ensayos físico-químicos. De los resultados obtenidos se concluye que ambos materiales tienen el mismo comportamiento, por lo que su elección estará determinada por la manejabilidad y aplicación del producto y no por su envejecimiento a largo plazo o incompatibilidad con la cerámica.Lastras Pérez, M.; Domenech Carbo, MT.; Carrascosa Moliner, MB.; Yusa Marco, DJ. (2007). Reposición de lagunas en cerámica arqueológica. Comparación de la escayola y un producto comercial ante ensayos de envejecimiento acelerado. Arché. (2):89-98. http://hdl.handle.net/10251/321888998

About the skull of `Cova del Parpalló¿ (Gandia): news on its diagnostic study and restoration

[ES] Uno de los retos que aborda el Laboratorio de Restauración del Museu de Prehistòria de València es el tratamiento de piezas que ya han sufrido en el pasado algún proceso de intervención. Por lo general se trata de materiales sobre los que se han empleado protecciones poco estables, refuerzos inadecuados o ¿rellenos¿ de faltantes aplicados de forma indiscriminada. En el presente artículo se presenta el estudio diagnóstico e intervención del cráneo y la mandíbula de un individuo femenino de Homo sapiens de la Cova del Parpalló (Gandia), correspondiente al Paleolítico superior. Esta pieza, tras su descubrimiento en 1930, fue llevada en 1935 al Laboratori d¿Arqueologia de la Universitat de Barcelona, donde fue reconstruida y restaurada no sin dificultad, añadiéndole refuerzos metálicos, adhesivos y reconstrucciones de ceras que claramente se presentaban ya envejecidas. Ha sido necesario, por tanto, llevar a cabo una nueva intervención y replantearse los criterios de actuación, avalados por los estudios analíticos pertinentes que han aportado información sobre la composición de los materiales empleados en la restauración anterior.[EN] One of the challenges of the Restoration Laboratory of the Museu de Prehistòria de València is the treatment of pieces that have suffered previous interventions in the past. This are generally materials that were restored with instable protections, inadequate reinforcements or missing fillers that were applied indiscriminately. This article shows the diagnostic study and intervention of the skull and mandible of a female Homo sapiens from `Cova del Parpalló¿ (Gandia), dated in the Upper Paleolithic. This piece, after its discovery in 1930, was taken in 1935 to the Laboratori d¿Arqueologia of the Universitat de Barcelona, where it was rebuilt and restored not without difficulty, adding metallic reinforcements, adhesives, and wax reconstructions which were clearly already aged. Therefore, it has been necessary to carry out a new intervention rethinking the performance criteria, backed by the relevant analytical studies that have provided information about the composition of the applied materials on the previous restoration.Pasíes Oviedo, T.; Renovell Anglés, C.; Domenech Carbo, MT.; Madrid García, JA.; Carrascosa Moliner, MB. (2020). Sobre el cráneo de la Cova del Parpalló (Gandia): novedades en su estudio diagnóstico y restauración. Archivo de Prehistoria Levantina. 33:255-282. http://hdl.handle.net/10251/167208S2552823