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1.
Ophthalmic Physiol Opt ; 44(3): 554-563, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38386250

RESUMEN

PURPOSE: To assess the impact of computer use on the ocular surface of individuals after laser in situ keratomileusis (LASIK). METHODS: The dry eye symptoms and ocular surface of 18 post-LASIK young individuals and 18 controls were evaluated before and after performing a 30-min task on a computer without (Visit 1) and with (Visit 2) initial instillation of artificial tears. Symptoms were assessed using the Ocular Surface Disease Index (OSDI), Symptom Assessment in Dry Eye questionnaire version two (SANDE II) and Computer Vision Syndrome Questionnaire (CVS-Q). The ocular surface was assessed by measuring corneal higher order aberrations, tear meniscus height (TMH), conjunctival redness, blink rate and incomplete blinking, lipid layer thickness (LLT) and non-invasive keratograph break-up time (NIKBUT). RESULTS: SANDE II scores were >0 after the computer task in both groups (p ≤ 0.01). SANDE II and CVS-Q scores did not differ between LASIK and controls (p ≥ 0.43). Greater bulbar-temporal conjunctival redness, TMH and LLT and shorter NIKBUT were found after computer use in the LASIK group (p ≤ 0.04), whereas no changes were observed in the controls (p ≥ 0.20). Lower SANDE II and CVS-Q scores were reported at Visit 2 compared with Visit 1 in both groups (p ≤ 0.01). Likewise, no worsening of dry eye signs was observed at Visit 2 (p ≥ 0.11). CONCLUSIONS: Ocular symptoms reported during computer use were comparable between the groups. However, a worsening of dry eye signs was mostly observed in post-LASIK individuals. The instillation of artificial tears was effective in preventing the effects of computer use on the ocular surface in post-LASIK patients.


Asunto(s)
Síndromes de Ojo Seco , Queratomileusis por Láser In Situ , Humanos , Queratomileusis por Láser In Situ/efectos adversos , Gotas Lubricantes para Ojos , Córnea , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/etiología , Computadores , Lágrimas
2.
Ophthalmic Physiol Opt ; 43(4): 885-897, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37073817

RESUMEN

PURPOSE: To assess changes in visual function and optical and tear film quality in computer users. METHODS: Forty computer workers and 40 controls were evaluated at the beginning and end of a working day. Symptoms were assessed using the Quality of Vision questionnaire (QoV), 5-item Dry Eye Questionnaire (DEQ-5) and Symptom Assessment in Dry Eye version II (SANDE II). Tear film quality was evaluated using the Medmont E300 dynamic corneal topography tool to measure the tear film surface quality (TFSQ), TFSQ area and auto tear break-up time (TBUT). Optical quality was assessed by measuring high, low and total ocular aberrations with a Hartmann-Shack wavefront sensor. Visual performance was assessed by measuring photopic and mesopic visual acuity, photopic and mesopic contrast sensitivity and light disturbance. RESULTS: Poorer DEQ-5, QoV and SANDE II scores were obtained in computer workers at the end of the working day compared with controls (p ≤ 0.02). Computer workers exhibited a higher (worse) TFSQ and TFSQ area at visit 2 compared with visit 1 (p ≤ 0.04), while no significant differences in TBUT (p = 0.19) or ocular aberrations were observed (p ≥ 0.09). Additionally, both light disturbance (p ≤ 0.04) and mesopic and photopic contrast sensitivity worsened at several spatial frequencies (p ≤ 0.04) throughout the working day in computer workers, while visual acuity remained unchanged (p ≥ 0.07). In contrast, control subjects exhibited no decrease in any variable during the day. CONCLUSIONS: While visual acuity remained unchanged, several aspects of visual function and quality of vision decreased over a day of computer use. These changes were accompanied by greater dry eye symptoms and tear film changes, which are likely to have played a fundamental role. The present study provides insight into new metrics to assess digital eye strain.


Asunto(s)
Síndromes de Ojo Seco , Visión Ocular , Humanos , Lágrimas , Agudeza Visual , Topografía de la Córnea , Síndromes de Ojo Seco/diagnóstico
3.
Graefes Arch Clin Exp Ophthalmol ; 260(2): 655-676, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34487223

RESUMEN

PURPOSE: This study aimed to develop and validate new metrics to objectively assess the lipid layer thickness (LLT) through the analysis of grey intensity values obtained from the Placido disk pattern reflected onto the tear film. METHODS: Ocular surface parameters were measured using Oculus Keratograph 5 M in 94 healthy volunteers (43.8 ± 26.8 years). Subjects' LLT was subjectively classified into 4 groups using an interferometry-based grading scale. New metrics based on the intensity of the Placido disk images were calculated and compared between groups. The repeatability of the new metrics and their diagnostic ability was analysed through receiver operating characteristics (ROC) curves. The level of agreement between the new objective tool and the existing subjective classification scale was analysed by means accuracy, weighted Kappa index and F-measure. RESULTS: Mean pixel intensity, median pixel intensity and relative energy at 5.33 s after blinking achieved the highest performance, with a correlation with LLT between r = 0.655 and 0.674 (p < 0.001), sensitivity between 0.92 and 0.94, specificity between 0.79 and 0.81, area under the ROC curve between 0.89 and 0.91, accuracy between 0.76 and 0.77, weighted Kappa index of 0.77 and F-measure between 0.86 and 0.87. CONCLUSION: The analysis of grey intensity values in videokeratography can be used as an objective tool to assess LLT. These new metrics could be included in a battery of clinical tests as an easy, repeatable, objective and accessible method to improve the detection and monitoring of dry eye disease and meibomian gland dysfunction.


Asunto(s)
Síndromes de Ojo Seco , Disfunción de la Glándula de Meibomio , Síndromes de Ojo Seco/diagnóstico , Humanos , Lípidos , Glándulas Tarsales , Lágrimas
4.
Graefes Arch Clin Exp Ophthalmol ; 260(4): 1183-1193, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34779906

RESUMEN

PURPOSE: This study aimed to assess the differences in blinking kinematics while reading on different digital displays and a control condition. METHODS: Thirty-two young healthy individuals were included in this prospective clinical study. The blinks of subjects were recorded for 150 s while reading on a laptop computer, tablet, e-reader, and smartphone and a control condition. Blinks were recorded using an eye-tracking device and were analyzed by means of image analysis to obtain a non-invasive detailed description of the blink movement. RESULTS: Blink rate decreased when reading on all displays compared to the control (p < 0.0005), although no differences were obtained amongst displays (p > 0.05). The percentage of incomplete blinks was higher with the computer compared to the control (p = 0.043), and lower with the smartphone compared to the rest of the conditions (p ≤ 0.015). Blink amplitude was smaller when reading from handheld devices compared to the control (p < 0.0005) and the computer (p ≤ 0.048). Closing and opening blink durations remained unvaried amongst conditions (p > 0.05), while opening and closing speeds were greater for the control and the computer compared to the handheld displays (p < 0.0005). Finally, contact and total blink durations were shorter during computer reading compared to the control (p = 0.004 and p = 0.017, respectively). CONCLUSION: Blinking kinematics vary considerably amongst displays and with respect to baseline, with these differences being probably attributed to differences in the way the displays are set up and the cognitive demand of the task.


Asunto(s)
Parpadeo , Computadores , Fenómenos Biomecánicos , Humanos , Estudios Prospectivos , Lectura
5.
Ophthalmic Physiol Opt ; 42(4): 797-806, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35394083

RESUMEN

PURPOSE: To assess the potential additive effects of short-term display use and contact lens (CL) wear on the ocular surface and tear film. METHODS: Thirty-four healthy volunteers (20.87 ± 2.33 years old) participated in this study. Participants' dry eye symptoms, ocular surface, tear film and pupil size were assessed before and after executing a 20-min reading task on a computer and a smartphone with and without CL wear, or with CL wear and artificial tear instillation. Measurements included the Ocular Surface Disease Index (OSDI) questionnaire; 5-item Dry Eye Questionnaire (DEQ-5); tear meniscus height (TMH); noninvasive keratograph break-up time (NIKBUT); bulbar conjunctival redness (BR) and pupil size. RESULTS: Higher symptoms were reported after reading on both displays with and without CLs (p ≤ 0.001) for short periods. BR was higher and NIKBUT shorter after reading on the computer regardless of wearing CLs (p ≤ 0.02 and p ≤ 0.02, respectively), while TMH increased for all conditions (p ≤ 0.02) except for CL computer reading (p = 0.23). Reading with CLs did not lead to greater signs of dry eye (BR, NIKBUT) and symptoms compared with reading unaided (p > 0.05), although a smaller increase in TMH was observed when reading on the computer with CLs (p = 0.005). Artificial tear instillation during CL wear led to a smaller increase in symptoms (p ≤ 0.02), a smaller increase in BR (p ≤ 0.04) and a decrease in NIKBUT (p = 0.02) compared to reading without correction. CONCLUSIONS: Disposable CL wear had no additive effects on signs and symptoms of dry eye when using digital devices for short periods. The instillation of artificial tears is an effective strategy for reducing the impact of display use in CL wearers.


Asunto(s)
Lentes de Contacto Hidrofílicos , Síndromes de Ojo Seco , Adolescente , Adulto , Lentes de Contacto Hidrofílicos/efectos adversos , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/etiología , Ojo , Humanos , Gotas Lubricantes para Ojos , Lágrimas , Adulto Joven
6.
Eye Contact Lens ; 48(10): 410-415, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36155946

RESUMEN

OBJECTIVES: To evaluate dry eye-related lifestyle and demographic factors associated with digital eye strain (DES). METHODS: An anonymous online survey was conducted in 851 university students. Participants were classified into DES (computer vision syndrome questionnaire [CVS-Q]≥6) or non-DES (CVS-Q<6). Respondents completed three dry eye questionnaires (Ocular Surface Disease Index [OSDI]; 5-item Dry Eye Questionnaire [DEQ-5]; 8-item Contact Lens Dry Eye Questionnaire) and were surveyed on dry eye risk factors contemplated by the Tear Film and Ocular Surface Society Dry Eye Workshop II. RESULTS: Six hundred twenty-eight participants were classified into the group with DES and 222 into the group without DES. Participants with DES slept fewer hours, spent more hours indoors with air conditioning, drank more caffeinated beverages, used the computer for longer periods, reported poorer health quality, and obtained a higher score in all questionnaires (P<0.025). A higher proportion of the participants were female, had several health disorders, and took several medications associated with dry eye (P<0.029). Multivariate logistic regression analysis revealed that stress (P=0.035), contact lens wear (P=0.011), hours of computer use per day (P=0.010), migraine headaches (P=0.013), and a higher OSDI (P<0.001) and DEQ-5 score (P<0.001) were associated with DES. CONCLUSIONS: Several dry eye-related risk factors and health conditions are associated with suffering from DES. Clinicians should acknowledge the relevance of triaging questions and dry eye disease risk factors when dealing with patients who view screens for extended periods.


Asunto(s)
Síndromes de Ojo Seco , Estudios Transversales , Síndromes de Ojo Seco/epidemiología , Síndromes de Ojo Seco/etiología , Femenino , Humanos , Masculino , Factores de Riesgo , Encuestas y Cuestionarios , Lágrimas
7.
Eye Contact Lens ; 48(10): 416-423, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36155947

RESUMEN

OBJECTIVES: To assess and compare the effectiveness of four main management strategies for preventing short-term effects of digital display use on dry eye signs and symptoms. METHODS: The ocular surface, tear film, and visual fatigue of 47 healthy individuals were assessed before and after reading on a laptop computer for 20 min under five different experimental conditions: control, instillation of artificial tears, taking a brief break, using a blue light screen filter, and blink control. Measurements included the Ocular Surface Disease Index (OSDI) Questionnaire, 5-item Dry Eye Questionnaire (DEQ-5), tear meniscus height (TMH), noninvasive keratograph break-up time (NIKBUT), bulbar conjunctival redness, and pupil size. RESULTS: Worse results were obtained after the control and blue light filter conditions in all variables (P≤0.037). A higher post-task DEQ-5 score (P=0.013) and TMH (P<0.0005) were obtained when taking a brief break compared with pretask, although the increase in symptoms was significantly smaller than that observed in the nonmanagement control condition (P≤0.036). Similarly, a smaller increase in OSDI and DEQ-5 was obtained with the use of artificial tears and blink control in comparison with the control condition (P≤0.008), whereas a greater increase in DEQ-5 and decrease in NIKBUT was obtained for the blue light filter condition in comparison with the instillation of artificial tears (P=0.017) or blink control (P=0.008), respectively. Finally, a significantly lower post-task pupil size was obtained for all the conditions (P≤0.027). CONCLUSIONS: The instillation of artificial tears and blink control were the best management strategies for preventing short-term effects of digital display use on dry eyes. Conversely, using a blue light filter did not offer any benefits.


Asunto(s)
Síndromes de Ojo Seco , Queratoconjuntivitis Seca , Parpadeo , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/prevención & control , Humanos , Gotas Lubricantes para Ojos , Lágrimas
8.
Graefes Arch Clin Exp Ophthalmol ; 259(5): 1323-1331, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33409681

RESUMEN

PURPOSE: The aim of this study is to develop a new objective semiautomatic method for analysing Meibomian glands visibility quantitatively. METHODS: One hundred twelve healthy volunteers aged between 18 and 90 years (48.29 ± 27.46 years) participated in this study. Infrared meibography was obtained from the right upper eyelid through Oculus Keratograph 5 M. Meibographies were classified into 3 groups: Group 1 = patients with good subjective glands visibility and a gland dropout percentage < 1/3 of the total Meibomian gland area; Group 2 = patients with low subjective glands visibility and a gland dropout < 1/3; and Group 3 = patients with low subjective glands visibility and a gland dropout > 1/3. New metrics based on the visibility of the Meibomian glands were calculated and later compared between groups. Rho Spearman test was used to assess the correlation between each metric, and Meibomian gland dropout percentage with the entire sample and after excluding Group 2. A p value less than 0.05 was defined as statistically significant. RESULTS: Fifty-six subjects were classified in Group 1 (24.48 ± 9.62 years), 19 in Group 2 (69.16 ± 21.30 years) and 37 in Group 3 (73.59 ± 13.70 years). No statistically significant differences were found between Groups 1 and 2 in dropout percentage. All metrics, with the exception of entropy, showed a higher Meibomian gland visibility in Group 1 than in the other two groups. Moderate correlations were statistically significant for all metrics with the exception of entropy. Correlations were higher after excluding Group 2. CONCLUSION: The proposed method is able to assess Meibomian gland visibility in an objective and repeatable way, which might help clinicians enhance Meibomian gland dysfunction diagnosis and follow-up treatment.


Asunto(s)
Síndromes de Ojo Seco , Enfermedades de los Párpados , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Glándulas Tarsales/diagnóstico por imagen , Persona de Mediana Edad , Proyectos de Investigación , Lágrimas , Adulto Joven
9.
Optom Vis Sci ; 98(9): 1045-1055, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34459466

RESUMEN

SIGNIFICANCE: The diagnosis of dry eye disease and meibomian gland dysfunction (MGD) is challenging. Measuring meibomian gland visibility may provide an additional objective method to diagnose MGD. PURPOSE: This study aimed to evaluate the ability of new metrics to better diagnose MGD, based on measuring meibomian gland visibility. METHODS: One hundred twelve healthy volunteers (age, 48.3 ± 27.5 years) were enrolled in this study. Ocular surface parameters were measured using the Oculus Keratograph 5M (Oculus GmbH, Wetzlar). Subjects were classified according to the presence or absence of MGD. New metrics based on the visibility of the meibomian glands were calculated and later compared between groups. The diagnostic ability of ocular surface parameters and gland visibility metrics was studied through receiver operating characteristic curves. Logistic regression was used to obtain the combined receiver operating characteristic curve of the metrics with the best diagnostic ability. RESULTS: Statistically significant differences were found between groups for all ocular surface parameters and new gland visibility metrics, except for the first noninvasive keratograph breakup time and gland expressibility. New gland visibility metrics showed higher sensitivity and specificity than did current single metrics when their diagnostic ability was assessed without any combination. The diagnostic capability increased when gland visibility metrics were incorporated into the logistic regression analysis together with gland dropout percentage, tear meniscus height, dry eye symptoms, and lid margin abnormality score (P < .001). The combination of median pixel intensity of meibography gray values and the aforementioned ocular surface metrics achieved the highest area under the curve (0.99), along with excellent sensitivity (1.00) and specificity (0.93). CONCLUSIONS: New meibomian gland visibility metrics are more powerful to diagnose MGD than current single metrics and can serve as a complementary tool for supporting the diagnosis of MGD.


Asunto(s)
Síndromes de Ojo Seco , Enfermedades de los Párpados , Disfunción de la Glándula de Meibomio , Adulto , Anciano , Síndromes de Ojo Seco/diagnóstico por imagen , Enfermedades de los Párpados/diagnóstico por imagen , Humanos , Glándulas Tarsales/diagnóstico por imagen , Persona de Mediana Edad , Lágrimas , Adulto Joven
10.
Eye Contact Lens ; 47(10): 565-572, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34224445

RESUMEN

OBJECTIVES: To assess the potential effects of switching to online lecture format on dry eye symptoms and dry eye disease (DED) risk factors. METHODS: An anonymous cross-sectional online survey was conducted in 812 university students (mean age, 21.5±4.0 years). Participants were classified according to the number of hours the participants took online lectures into online students or in-person students. Respondents completed a total of three DED questionnaires (Ocular Surface Disease Index [OSDI]; 5-item Dry Eye Questionnaire; 8-item Contact Lens Dry Eye Questionnaire) and were surveyed on dry eye risk factors contemplated by the Tear Film and Ocular Surface Society Dry Eye Workshop II in addition to other factors potentially linked to dry eye. RESULTS: Five hundred twenty-three subjects (64.4%) were classified into the online group and 289 (35.6%) into the in-person group. No statistically significant age (P=0.266) or sex (P=0.423) differences were found between groups. Students taking online lectures used the computer more, spent less time outdoors, practised more exercise, wore a face mask for less time, experienced fewer allergies and fewer psoriasis episodes, and obtained a higher OSDI score (P<0.029 for all). Multivariate logistic regression analysis revealed that the hours of online lectures taken per week was independently associated with having a positive OSDI score (P=0.022). CONCLUSIONS: Taking online lectures is independently associated with having dry eye symptoms. Despite a lower prevalence of DED risk factors, a higher computer use is probably behind the greater ocular dryness reported by online students.


Asunto(s)
COVID-19 , Síndromes de Ojo Seco , Adolescente , Adulto , Estudios Transversales , Síndromes de Ojo Seco/epidemiología , Humanos , Pandemias , Factores de Riesgo , SARS-CoV-2 , Encuestas y Cuestionarios , Lágrimas , Adulto Joven
11.
Int Ophthalmol ; 41(7): 2473-2483, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33728492

RESUMEN

PURPOSE: The aim of this study is to assess the intraexaminer repeatability of Non-invasive Keratograph Break-Up Time (NIKBUT) obtained using the Oculus Keratograph 5M (K5M), given its relevance as a homeostasis marker in Dry Eye Disease (DED). METHODS: In total, 80 healthy volunteers aged between 30 and 89 years participated. Measurements were classified according to age, sex and the presence or not of DED. Repeatability was evaluated by the calculation of within-subject standard deviation (Sw), coefficient of repeatability (CoR) and coefficient of variation (CoV). Moreover, the Passing-Bablok regression method was applied. RESULTS: Sw, CoR and CoV coefficients showed low repeatability in all groups with values between 3.57 and 7.14; 9.90 and 19.79; and 51.90 and 65.49, for each coefficient, respectively. No statistically significant differences were found in the NIKBUT measurements between healthy and DED patients (p = 0.188). Groups with more DED risk had better repeatability. Passing-Bablok regression also confirmed a lack of agreement between the maximum and minimum NIKBUT measurement. CONCLUSION: NIKBUT measurement has low intraexaminer repeatability even when considering sex, age and DED diagnosis. Nevertheless, not only is this low repeatability due to the device, but also it is largely due to the intrinsic variability of the tear film.


Asunto(s)
Síndromes de Ojo Seco , Lágrimas , Adulto , Anciano , Anciano de 80 o más Años , Síndromes de Ojo Seco/diagnóstico , Voluntarios Sanos , Humanos , Persona de Mediana Edad , Estudios Prospectivos
12.
Graefes Arch Clin Exp Ophthalmol ; 258(12): 2701-2714, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32524240

RESUMEN

PURPOSE: The objective of this study was to analyze the differences in blinking kinematics of spontaneous and voluntary blinks using for the first time a self-developed, non-invasive, and image processing-based method. METHODS: The blinks of 30 subjects were recorded for 1 min with the support of an eye-tracking device based on a high-speed infrared video camera, working at 250 frames per second, under two different experimental conditions. For the first condition, subjects were ordered to look in the straightforward position at a fixation target placed 1 m in front of them, with no further instructions. For the second, subjects were additionally asked to blink only following a sound signal every 6 s. RESULTS: Mean complete blinks increased by a factor of 1.7 from the spontaneous to the voluntary condition while mean incomplete blinks reduced significantly by a factor of 0.4. In both conditions, closing mean and peak velocities were always significantly greater and durations significantly lower than opening ones. When comparing the values for each condition, velocities and amplitudes for the voluntary condition were always greater than the corresponding values for spontaneous. CONCLUSION: Voluntary blinks revealed significant kinematic differences compared to spontaneous, thus supporting a different supranuclear pathway organization. This study presents a new method, based on image analysis, for the non-invasive kinematic characterization of blinking.


Asunto(s)
Parpadeo , Procesamiento de Imagen Asistido por Computador , Fenómenos Biomecánicos , Humanos , Proyectos de Investigación
13.
Optom Vis Sci ; 97(12): 1070-1079, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33259378

RESUMEN

SIGNIFICANCE: Digital display use has been accepted as a contributing factor to dry eye disease. Nowadays, plenty of new models of digital displays have been developed, and the differences in their nature and the ways in which they are set and used may contribute to differences in the eye-related problems they cause. PURPOSE: This study aimed to analyze the differences in ocular surface, tear film, and visual fatigue parameters after reading on different digital displays, with and without initial instillation of artificial tears. METHODS: Thirty-one healthy individuals ranging in age from 20 to 26 years (mean ± standard deviation, 21.26 ± 1.73 years) were included in this prospective clinical study. Subjects' ocular surface, tear film, and visual fatigue parameters were assessed after reading for 15 minutes on a laptop computer, tablet, e-reader, and smartphone with matching characteristics and a baseline measurement. Measurements were taken with and without the instillation of artificial tears before the reading tasks and included the Ocular Surface Disease Index questionnaire, the Computer Vision Syndrome Questionnaire, tear meniscus height, the Schirmer I test, noninvasive keratograph break-up time, osmolarity, bulbar redness, and pupil size. RESULTS: Statistically significant differences in the Ocular Surface Disease Index, Computer Vision the Syndrome Questionnaire, tear meniscus height, the Schirmer I test, noninvasive keratograph break-up time, osmolarity, and bulbar redness were obtained when comparing the displays (P < .05). Best results were obtained with the smartphone and the e-reader. Conversely, the computer produced the highest disturbance on the ocular surface and tear film. Finally, the instillation of artificial tears revealed no statistical improvement of ocular surface or tear film parameters for the same device (P > .05). CONCLUSIONS: Taking into account the clinical tests for dry eye diagnosis, the smartphone may be considered as the least disturbing display, producing lower dry eye signs and symptoms in comparison with other devices.


Asunto(s)
Astenopía/fisiopatología , Computadoras de Mano , Síndromes de Ojo Seco/fisiopatología , Lectura , Lágrimas/fisiología , Adulto , Femenino , Humanos , Gotas Lubricantes para Ojos/administración & dosificación , Masculino , Concentración Osmolar , Estudios Prospectivos , Encuestas y Cuestionarios , Adulto Joven
14.
Ophthalmic Physiol Opt ; 40(6): 718-727, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32885875

RESUMEN

PURPOSE: To compare the optical and visual performance of a dual-focus (DF) contact lens used for myopia control with a single-vision (SV) contact lens of the same material. METHODS: A randomised, double-masked crossover study. Twenty-eight healthy, myopic volunteers between 18 and 32 years of age (23.49 ± 4.07 years) participated in this study. The sensory dominant eye for distance vision was determined. Refraction, best-corrected visual acuity (VA) and aberrations for 3 mm and 5 mm pupil diameters were quantified without a contact lens in situ. Subjects were fitted with two contact lens designs: DF and SV, both made of omafilcon A material. The Quality of Vision (QoV) questionnaire, over-refraction, best-corrected VA, stereopsis at 40 cm, best-corrected photopic and mesopic contrast sensitivity, light disturbance and aberrations were assessed 25 min after contact lens insertion. RESULTS: There were no statistically significant differences in best-corrected VA and stereopsis between the baseline, DF and SV conditions. Photopic and mesopic contrast sensitivity were lower for the DF contact lens at all frequencies, with the exception of the mesopic contrast sensitivity at 18 cycles per degree (p = 0.23). Higher order aberrations and light disturbance size and irregularity were higher for the DF contact lens (p < 0.001). No differences were found in higher order aberrations between baseline and the SV contact lens condition for each pupil diameter. QoV scores also revealed lower frequency, severity and bothersome scores with the SV contact lens than with the DF contact lens (p < 0.001). CONCLUSIONS: The DF contact lens design decreased the psychophysical and psychometric visual quality scores in the short-term under dim-light conditions when compared with a single-vision contact lens design of the same material. VA and stereopsis were unaffected by the lens design.


Asunto(s)
Visión de Colores/fisiología , Lentes de Contacto Hidrofílicos , Sensibilidad de Contraste/fisiología , Miopía/fisiopatología , Agudeza Visual , Adolescente , Adulto , Estudios Cruzados , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Masculino , Miopía/terapia , Factores de Tiempo , Adulto Joven
15.
Sensors (Basel) ; 20(18)2020 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-32971791

RESUMEN

This paper presents an accuracy assessment of the main global scale Burned Area (BA) products, derived from daily images of the Moderate-Resolution Imaging Spectroradiometer (MODIS) Fire_CCI 5.1 and MCD64A1 C6, as well as the previous versions of both products (Fire_CCI 4.1 and MCD45A1 C5). The exercise was conducted on the boreal region of Alaska during the period 2000-2017. All the BA polygons registered by the Alaska Fire Service were used as reference data. Both new versions doubled the annual BA estimate compared to the previous versions (66% for Fire_CCI 5.1 versus 35% for v4.1, and 63% for MCD64A1 C6 versus 28% for C5), reducing the omission error (OE) by almost one half (39% versus 67% for Fire_CCI and 48% versus 74% for MCD) and slightly increasing the commission error (CE) (7.5% versus 7% for Fire_CCI and 18% versus 7% for MCD). The Fire_CCI 5.1 product (CE = 7.5%, OE = 39%) presented the best results in terms of positional accuracy with respect to MCD64A1 C6 (CE = 18%, OE = 48%). These results suggest that Fire_CCI 5.1 could be suitable for those users who employ BA standard products in geoinformatics analysis techniques for wildfire management, especially in Boreal regions. The Pareto boundary analysis, performed on an annual basis, showed that there is still a potential theoretical capacity to improve the MODIS sensor-based BA algorithms.

16.
J Cogn Neurosci ; 31(4): 469-481, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30457917

RESUMEN

Objects that promise rewards are prioritized for visual selection. The way this prioritization shapes sensory processing in visual cortex, however, is debated. It has been suggested that rewards motivate stronger attentional focusing, resulting in a modulation of sensory selection in early visual cortex. An open question is whether those reward-driven modulations would be independent of similar modulations indexing the selection of attended features that are not associated with reward. Here, we use magnetoencephalography in human observers to investigate whether the modulations indexing global color-based selection in visual cortex are separable for target- and (monetary) reward-defining colors. To assess the underlying global color-based activity modulation, we compare the event-related magnetic field response elicited by a color probe in the unattended hemifield drawn either in the target color, the reward color, both colors, or a neutral task-irrelevant color. To test whether target and reward relevance trigger separable modulations, we manipulate attention demands on target selection while keeping reward-defining experimental parameters constant. Replicating previous observations, we find that reward and target relevance produce almost indistinguishable gain modulations in ventral extratriate cortex contralateral to the unattended color probe. Importantly, increasing attention demands on target discrimination increases the response to the target-defining color, whereas the response to the rewarded color remains largely unchanged. These observations indicate that, although task relevance and reward influence the very same feature-selective area in extrastriate visual cortex, the associated modulations are largely independent.


Asunto(s)
Atención/fisiología , Percepción de Color/fisiología , Potenciales Evocados/fisiología , Recompensa , Corteza Visual/fisiología , Adulto , Sesgo Atencional/fisiología , Humanos , Magnetoencefalografía , Adulto Joven
17.
Eye Contact Lens ; 45(1): 40-45, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29944498

RESUMEN

OBJECTIVES: To investigate the ocular surface of an aged population wearing a daily disposable contact lens (CL) over their 1st day of wear. METHODS: Forty eyes from 40 presbyopic subjects were fitted a daily CL (Delefilcon A). Tear osmolarity, tear meniscus area (TMA), and ocular surface aberrations (total higher-order root mean square [RMS]) were assessed at baseline (t0), at 20 min (t1) and after 8 hr (t2) of wear. Fluorescein corneal and conjunctival staining and tear breakup time (TBUT) were performed at t0 and t2. RESULTS: No statistically significant changes were found between t0, t1, and t2 for TMA and between t0 and t2 for fluorescein corneal and conjunctival staining. Tear breakup time worsened by the end of the day from 10.4±0.4 sec t0 to 9.0±0.3 sec t2 (P<0.05). Osmolarity showed significant changes between t0 306.9±2.3 mOsm/L and t1 312.4±2.4 mOsmol/L (P=0.02) but returned to baseline values at 8 hr (310.40±2.26 mOsm/L; P=0.09). Total higher-order RMS showed significant changes between t0 0.38±0.02 µm and t1 0.61±0.04 µm (P≤0.001) and between t0 and t2 0.64±0.41 µm (P≤0.001). CONCLUSIONS: Delefilcon A may induce measures changes (osmolarity and TBUT values) in a presbyopic population; however, TMA and vital staining were maintained at the baseline level over the day.


Asunto(s)
Envejecimiento/fisiología , Lentes de Contacto Hidrofílicos , Equipos Desechables , Síndromes de Ojo Seco/terapia , Satisfacción del Paciente , Presbiopía/terapia , Lágrimas/química , Adulto , Conjuntiva/metabolismo , Córnea/metabolismo , Síndromes de Ojo Seco/metabolismo , Diseño de Equipo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Concentración Osmolar , Presbiopía/fisiopatología , Estudios Prospectivos , Visión Ocular
18.
Blood ; 127(24): 3004-14, 2016 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-26966091

RESUMEN

The spectrum of somatic alterations in hematologic malignancies includes substitutions, insertions/deletions (indels), copy number alterations (CNAs), and a wide range of gene fusions; no current clinically available single assay captures the different types of alterations. We developed a novel next-generation sequencing-based assay to identify all classes of genomic alterations using archived formalin-fixed paraffin-embedded blood and bone marrow samples with high accuracy in a clinically relevant time frame, which is performed in our Clinical Laboratory Improvement Amendments-certified College of American Pathologists-accredited laboratory. Targeted capture of DNA/RNA and next-generation sequencing reliably identifies substitutions, indels, CNAs, and gene fusions, with similar accuracy to lower-throughput assays that focus on specific genes and types of genomic alterations. Profiling of 3696 samples identified recurrent somatic alterations that impact diagnosis, prognosis, and therapy selection. This comprehensive genomic profiling approach has proved effective in detecting all types of genomic alterations, including fusion transcripts, which increases the ability to identify clinically relevant genomic alterations with therapeutic relevance.


Asunto(s)
Dermatoglifia del ADN/métodos , Perfilación de la Expresión Génica/métodos , Genómica/métodos , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo , Aberraciones Cromosómicas , Técnicas de Laboratorio Clínico/métodos , Análisis Mutacional de ADN/métodos , ADN de Neoplasias/análisis , Regulación Neoplásica de la Expresión Génica , Neoplasias Hematológicas/patología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mutación , Polimorfismo Genético , ARN Neoplásico/análisis , Sensibilidad y Especificidad , Integración de Sistemas
19.
Int Ophthalmol ; 38(3): 933-941, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28444524

RESUMEN

PURPOSE: To assess the in vitro optical quality of monofocal aspheric toric intraocular lenses (IOLs) as a function of the cylindrical power. METHODS: The in vitro optical quality of the AcrySof IQ Toric IOLs SN6AT2, SN6AT3, SN6AT4, SN6AT5 and SN6AT6 (Alcon Laboratories Inc., Forth Worth, TX, USA) was assessed with an instrument conceived for measuring Zernike's coefficients at 3.0- and 5.0-mm apertures. As a reference, the aspheric monofocal lens AcrySof IQ Aspheric SN60WF (Alcon Laboratories Inc., Forth Worth, TX, USA) was also measured. The area of visibility and cut-off frequency were used to describe the modulation transfer function (MTF) of each lens; meanwhile, the light in the bucket and the diameter of a circular area centred on the point-spread function (PSF) peak that captures 50% of the light energy were used to describe the PSF of each lens. Finally, an image simulation was computed from the Zernike values with reference purposes. RESULTS: Small differences were found on the metrics used for describing the MTF and PSF of the lenses at both tested apertures, but these were not statistically significant (p > 0.05). Furthermore, the image simulation showed that these differences would not have clinical relevance at all. CONCLUSIONS: The optical performance of the AcrySof IQ toric IOLs in terms of MTF and PSF is good and seems to be independent of the cylindrical power and similar to a non-toric aspheric lens.


Asunto(s)
Astigmatismo/rehabilitación , Lentes Intraoculares/normas , Óptica y Fotónica/normas , Aberrometría , Humanos , Diseño de Prótesis , Refracción Ocular
20.
Proc Biol Sci ; 284(1866)2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29118141

RESUMEN

The ability to spontaneously feel a beat in music is a phenomenon widely believed to be unique to humans. Though beat perception involves the coordinated engagement of sensory, motor and cognitive processes in humans, the contribution of low-level auditory processing to the activation of these networks in a beat-specific manner is poorly understood. Here, we present evidence from a rodent model that midbrain preprocessing of sounds may already be shaping where the beat is ultimately felt. For the tested set of musical rhythms, on-beat sounds on average evoked higher firing rates than off-beat sounds, and this difference was a defining feature of the set of beat interpretations most commonly perceived by human listeners over others. Basic firing rate adaptation provided a sufficient explanation for these results. Our findings suggest that midbrain adaptation, by encoding the temporal context of sounds, creates points of neural emphasis that may influence the perceptual emergence of a beat.


Asunto(s)
Percepción Auditiva/fisiología , Gerbillinae/fisiología , Colículos Inferiores/fisiología , Música , Desempeño Psicomotor , Estimulación Acústica , Adulto , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
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