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Browsing by UCM subject "Técnicas de la imagen"

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10-Fold Quantum Yield Improvement of Ag2S Nanoparticles by Fine Compositional Tuning
(ACS, 2020-02-18) Ortega Rodríguez, Alicia; Shen, Yingli; Zabala Gutiérrez, Irene; Santos, Harrison D. A.; Torres Vera, Vivian; Ximedes, Erving; Villaverde Cantizano, Gonzalo; Lifante, José; Gerke, Christoph; Fernández Monsalve, Nuria; Gómez Calderón, Óscar; Melle Hernández, Sonia; Marqués Hueso, José; Méndez González, Diego; Laurenti, Marco; Jones, Callum M. S.; López Romero, Juan Manuel; Contreras Cáceres, Rafael; Jaque García, Daniel; Rubio Retama, Jorge; Garma Pons, Santiago
Ag2S semiconductor nanoparticles (NPs) are near-infrared luminescent probes with outstanding properties (good biocompatibility, optimum spectral operation range, and easy biofunctionalization) that make them ideal probes for in vivo imaging. Ag2S NPs have, indeed, made possible amazing challenges including in vivo brain imaging and advanced diagnosis of the cardiovascular system. Despite the continuous redesign of synthesis routes, the emission quantum yield (QY) of Ag2S NPs is typically below 0.2%. This leads to a low luminescent brightness that avoids their translation into the clinics. In this work, an innovative synthetic methodology that permits a 10-fold increment in the absolute QY from 0.2 up to 2.3% is presented. Such an increment in the QY is accompanied by an enlargement of photoluminescence lifetimes from 184 to 1200 ns. The optimized synthetic route presented here is based on a fine control over both the Ag core and the Ag/S ratio within the NPs. Such control reduces the density of structural defects and decreases the nonradiative pathways. In addition, we demonstrate that the superior performance of the Ag2S NPs allows for high-contrast in vivo bioimaging. .
A Comparative Study of Two Imaging Techniques of Meibomian Glands
(Multidisciplinary Digital Publishing Institute, 2023-03-15) Diz Arias, Elena; Fernández Jiménez, Elena; Peral Cerdá, Assumpta; Gómez Pedrero, José Antonio
In the present study, two different meibographers, Oculus Keratograph 5M (K5M) that uses 840 nm infrared light and the Visible Light Non-Contact Meibographer (VLNCM) that uses 610 nm visible light have been used to obtain meibography images from normal and Meibomian Gland Dysfunction (MGD) population. The main objective has been to validate and demonstrate that the use of visible light is useful for observation and quantification of MG in clinical practice. Twenty participants were enrolled in this prospective study. The upper eyelids of one randomly chosen eye were used to obtain results. Forty images were captured and analysed. Three specialized observers were recruited to grade images using Pult and Riede Pult 5-degree scale, in two different sessions. Intra-observer agreement between sessions for both devices was shown. Inter-observer variability analysis showed discrepancy between meiboscores obtained from observers with K5M (p-value < 0.05), except for session 2 in the pathology group, while no statistical difference was found with VLNCM. Repeatability analysis found no statistically significant differences between sessions. Correlation between meibographers showed no statistically significant difference and a moderate correlation coefficient between meiboscores graded with the two devices. The current study suggests that VLNCM can allow MG to be properly visualized and classified in the upper eyelids.
A Diagnostic Calculator for Detecting Glaucoma on the Basis of Retinal Nerve Fiber Layer, Optic Disc, and Retinal Ganglion Cell Analysis by Optical Coherence Tomography
(The Association for Research in Vision and Ophthalmology, Inc., 2015-10) Larrosa Povés, José Manuel; Moreno Montañes, Javier; Martinez de la Casa, Jose Maria; Polo Llorens, Vicente; Velázquez Villoria, Álvaro; Berrozpe Villabona, Clara; García Granero, Marta
Purpose: The purpose of this study was to develop and validate a multivariate predictive model to detect glaucoma by using a combination of retinal nerve fiber layer (RNFL), retinal ganglion cell-inner plexiform (GCIPL), and optic disc parameters measured using spectral-domain optical coherence tomography (OCT). Methods: Five hundred eyes from 500 participants and 187 eyes of another 187 participants were included in the study and validation groups, respectively. Patients with glaucoma were classified in five groups based on visual field damage. Sensitivity and specificity of all glaucoma OCT parameters were analyzed. Receiver operating characteristic curves (ROC) and areas under the ROC (AUC) were compared. Three predictive multivariate models (quantitative, qualitative, and combined) that used a combination of the best OCT parameters were constructed. A diagnostic calculator was created using the combined multivariate model. Results: The best AUC parameters were: inferior RNFL, average RNFL, vertical cup/disc ratio, minimal GCIPL, and inferior-temporal GCIPL. Comparisons among the parameters did not show that the GCIPL parameters were better than those of the RNFL in early and advanced glaucoma. The highest AUC was in the combined predictive model (0.937; 95% confidence interval, 0.911–0.957) and was significantly (P = 0.0001) higher than the other isolated parameters considered in early and advanced glaucoma. The validation group displayed similar results to those of the study group. Conclusions: Best GCIPL, RNFL, and optic disc parameters showed a similar ability to detect glaucoma. The combined predictive formula improved the glaucoma detection compared to the best isolated parameters evaluated. The diagnostic calculator obtained good classification from participants in both the study and validation groups.
A Novel Automated Approach for Infrared-Based Assessment of Meibomian Gland Morphology
(ARVO, 2019-07) Llorens Quintana, Clara; Rico del Viejo, Laura; Syga, Piotr; Madrid Costa, David; Iskander, Robert
Purpose: We present and validate a new methodology for analyzing, in an automated and objective fashion, infrared images of the meibomian glands (MG). Methods: The developed algorithm consists of three main steps: selection of the region of interest, detection of MG, and analysis of MG morphometric parameters and dropout area (DOA). Additionally, a new approach to quantify the irregularity of MG is introduced. We recruited 149 adults from a general population. Infrared meibography, using Keratograph 5M, was performed. Images were assessed and graded subjectively (Meiboscore) by two experienced clinicians and objectively with the proposed automated method. Results: The correlation of subjective DOA assessment between the two clinicians was poor and the average percentage of DOA estimated objectively for each Meiboscore group did not lie within their limits. The objective assessment showed lower variability of meibography grading than that obtained subjectively. Additionally, a new grading scale of MG DOA that reduces intraclass variation is proposed. Reported values of MG length and width were inversely proportional to the DOA. Gland irregularity was objectively quantified. Conclusions: The proposed automatic and objective method provides accurate estimates of the DOA as well as additional morphologic parameters that could add valuable information in MG dysfunction understanding and diagnosis. Translational Relevance: This approach highlights the shortcomings of currently used subjective methods, and provides the clinicians with an objective, quantitative and less variable alternative for assessing MG in a noninvasive and automated fashion. It provides a viable alternative to more time-consuming subjective methods.
Actualización automática de los ficheros diagnóstico de enfermedades neoplásicas, según los sistemas de la OMS y de la UICC
(Universidad Complutense de Madrid, 2015) Eleno Álvarez, Alfonso; Gil Gayarre, Miguel
Agreement between the biometric measurements used to calculate the size of the implantable collamer lenses measured with four different technologies
(Wolters Kluwer Medknow Publications, 2022-04-28) Calvo Sanz, Jorge Antonio; Poyales Galán, Francisco; Zhou, Ying; Arias Puente, Alfonso; Garzón Jiménez, Nuria
Purpose: To evaluate the agreement between the biometric measurements used to calculate the size of the implantable collamer lenses (ICL) with different technologies: swept-source optical coherence tomography, spectral domain optical coherence tomography, and Scheimpflug tomography. Methods: This retrospective observational study included subjects undergoing refractive surgery with posterior chamber phakic IOL implantation to correct their myopia. The anterior chamber depth (ACD) and the horizontal white to white (WTW) or the angle to angle (ATA) distance were measured with the following four devices: the IOLMaster 700 biometer (Carl Zeiss Meditec, Jena, Germany), based on swept-source optical coherence tomography; the Cirrus and Visante optical coherence tomographs (Carl Zeiss Meditec) based on low-coherence interferometry; and the Pentacam rotating Scheimpflug camera (Oculus, Wetzlar, Germany). Results: In the horizontal corneal diameter measurements, there were statistically significant differences between Pentacam–IOLMaster 700 pair (P < 0.001) and Pentacam–Visante pair (P < 0.001). WTW from CIRRUS showed the lowest correlation when paired with Pentacam and IOLMaster 700 (R2 = 0.452 and 0.385 for Visante and R2 = 0.494 and 0.426 for Cirrus). Regarding the linear correlation of the ACD measurements, all pairs of devices were statistically significant and all of them showed a very good correlation index. Conclusion: There is a good agreement between the different devices under evaluation for ACD measurements. As for WTW, the values measured with the different devices showed large discrepancies with low correlation levels, especially when comparing the tomographs with the other devices under evaluation.
Analysis of inner and outer retinal layers using spectral domain optical coherence tomography automated segmentation software in ocular hypertensive and glaucoma patients
(Public Library Science, 2018-04-19) Cifuentes Canorea, Pilar; Ruiz Medrano, Jorge; Gutierrez Bonet, Rosa; Peña García, Pablo; Sáenz Francés, Federico; García Feijoo, Julián; Martínez de la Casa, Jose Maria
Objective: To analyse the morphological features and diagnostic ability of eight macular retinal layers using a new segmentation software Heidelberg's Spectralis Optical Coherence Tomography (SD-OCT) in healthy, ocular hypertensive and primary open angle glaucoma patients. Methods: Single-center, cross-sectional, non-interventional study. 193 eyes from 193 consecutive patients (56 controls, 63 ocular hypertensives, 32 early primary open glaucoma patients and 42 moderate-advanced primary open glaucoma patients). Those patients presenting any retinal disease were excluded. Macular segmentation of the retinal layers was automatically performed using the new segmentation Heidelberg's Spectralis OCT software providing measurements for eight retinal layers. The software provides thickness maps divided into nine subfields. Results: Statistically significant differences in inner layers’ thickness was found between all 4 four groups. Superior and inferior sectors of macular retinal nerve fiber layer; nasal, temporal, superior and inferior sectors of ganglion cell layer and inner plexiform layer were significantly different when comparing ocular hypertensive patients and early glaucoma patients. Areas under the ROC curves for early glaucoma diagnosis were 0.781±0.052 for macular retinal nerve fiber layer outer inferior sector, 0.760±0.050 for ganglion cell layer outer temporal sector, 0.767±0.049 for the inner plexiform layer outer temporal sector and 0.807±0.048 for the combination of all three. No differences were found between groups when considering outer retinal layers. Conclusions: The automated segmentation software from Heidelberg's Spectralis OCT provides a new diagnostic tool for the diagnosis of ocular hypertensive and glaucoma patients.
Atlas electrónico de registros retinográficos y tomográficos: cribado, derivación, diagnóstico diferencial y seguimiento de afecciones retinianas. Parte II: Glaucoma
(2015) Sánchez Ramos, Celia; Bonnin Arias, Cristina; Pérez Carrasco, Ma. Jesús; Martinez de la Casa, José María
Esta segunda parte de Atlas electrónico retinográfico y tomográfico constituye una completa base de datos de screening y diagnóstico de glaucoma que sirve tanto de material de aprendizaje y autoevaluación para estudiantes, así como de material de consulta y comparación para profesionales del área de Ciencias de la Visión y Oftalmología.
Berger’s space
(Elsevier España, 2019-09-12) Santos Bueso, Enrique
Introduction and Objective: The Berger’s space (BS) is a space located between the posterior capsule of the lens and the anterior hyaloid of the vitreous, structures that adhere in a circular manner by means of the Wieger ligament, for which the outer limit is defined by Egger´s line. The aim of this article is to perform a review of the BS, as well as to present three cases in which this BS could be demonstrated by optical coherence tomography (OCT). Material and Method: A total of 90 patients from a general ophthalmology clinic were studied, on whom an anterior pole OCT was performed (Cirrus Lumera 700 Carl Zeiss Medicte, Dublin, California, United States). All patients were included consecutively, with an analysis being performed on the cornea, anterior chamber, iris, lens, and anterior vitreous, but excluding those in which the test could not be performed. Results: The posterior lens capsule, the anterior hyaloid, and the BS between both structures were observed in three patients. This is the first time in the current literature that three cases have been described, together with their characteristics (one phakic –case 1- and two pseudophakic, one of them vitreous destructuring –case 2- and the other with opacification of the posterior capsule of the lens –case 3-), using this previous pole OCT technique. Conclusions: Knowledge of the BS is essential to understand the vitreo-lenticular junction and any complications in some cataract surgeries, as well as to also understand the pathological origin of pigment dispersion syndrome.
Boosting the Near-Infrared Emission of Ag2S Nanoparticles by a Controllable Surface Treatment for Bioimaging Applications
(ACS Publications, 2022-01) Zabala Gutiérrez, Irene; Gerke, Christoph; Shen, Yingli; Ximendes, Erving Clayton; Manso Silvan, Miguel; Marin, Riccardo; Jaque García, Daniel; Gómez Calderón, Óscar; Melle Hernández, Sonia; Rubio Retama, Jorge
Ag2S nanoparticles are the staple for high-resolution preclinical imaging and sensing owing to their photochemical stability, low toxicity, and photoluminescence (PL) in the second near-infrared biological window. Unfortunately, Ag2S nanoparticles exhibit a low PL efficiency attributed to their defective surface chemistry, which curbs their translation into the clinics. To address this shortcoming, we present a simple methodology that allows to improve the PL quantum yield from 2 to 10%, which is accompanied by a PL lifetime lengthening from 0.7 to 3.8 μs. Elemental mapping and X-ray photoelectron spectroscopy indicate that the PL enhancement is related to the partial removal of sulfur atoms from the nanoparticle’s surface, reducing surface traps responsible for nonradiative de-excitation processes. This interpretation is further backed by theoretical modeling. The acquired knowledge about the nanoparticles’ surface chemistry is used to optimize the procedure to transfer the nanoparticles into aqueous media, obtaining water-dispersible Ag2S nanoparticles that maintain excellent PL properties. Finally, we compare the performance of these nanoparticles with other near-infrared luminescent probes in a set of in vitro and in vivo experiments, which demonstrates not only their cytocompatibility but also their superb optical properties when they are used in vivo, affording higher resolution images.
Changes in corneal biomechanical properties after 24 hours of continuous intraocular pressure monitoring using a contact lens sensor
(Canadian Ophthalmology Society; Elsevier, 2017-12-18) Morales Fernández, Laura; García Bella, Javier; Martínez de la Casa, Jose Maria; Sánchez Jean, Rubén; Sáenz Francés, Federico; Arriola Villalobos, Pedro; Perucho González, Lucía; Santos Bueso, Enrique; García Feijoo, Julián
Objective: This study was designed to assess changes in corneal topography and biomechanics after intraocular pressure (IOP) monitoring using the Triggerfish contact lens sensor (CLS). Methods: For this prospective study, 30 eyes of 30 subjects: 14 healthy subjects (G1) and 6 glaucoma patients (G2), were recruited for 24 hours of continuous IOP monitoring using the CLS. The following measurements were taken before CLS fitting and after lens removal: maximum keratometry (Kmax), mean keratometry (MK), and corneal astigmatism (Cyl) measured through Pentacam corneal topography, and the corneal biomechanical variables corneal hysteresis (CH) and corneal resistance factor (CRF) measured with the Ocular Response Analyzer (ORA). Results: Pentacam data revealed significant changes after CLS removal in Kmax (+3.14 ± 2.46 D, p = 0.002), MK (+0.52 ± 0.63 D, p = 0.02), and Cyl (+0.48 ± 0.53 D, p = 0.019) in G1; and Kmax (+1.38 ± 1.43 D, p = 0.002) in G2. The changes observed were more pronounced in G1 than in G2 but differences were not significant. The ORA results indicated higher CH (11.35 ± 2.42 vs 8.17 ± 2.09) and CRF (10.3 ± 2.03 vs 9.1 ± 1.81) before lens fitting in G1 than G2, while no significant changes were produced after CLS removal in either group. Conclusions: The use of CLS for IOP monitoring over 24 hours caused topographic changes in both healthy subjects and glaucoma patients. No changes were produced in corneal biomechanics.
Changes in Retinal OCT and Their Correlations with Neurological Disability in Early ALS Patients, a Follow-Up Study
(MDPI AG, 2019-12) Rojas Lozano, Pilar; Hoz Montañana, María Rosa de; Ramírez Sebastián, Ana Isabel; Ferreras, Antonio; García Martín, Elena Salobrar; Muñóz Blanco, José L; Urcelay Segura, José Luis; Salazar Corral, Juan José; Ramirez Sebastian, Jose Manuel
Background: To compare early visual changes in amyotrophic lateral sclerosis (ALS) patients with healthy controls in a baseline exploration, to follow-up the patients after 6 months, and to correlate these visual changes with neurological disability. Methods: All patients underwent a comprehensive neurological and ophthalmological examination. A linear mixed analysis and Bonferroni p-value correction were performed, testing four comparisons as follows: Control baseline vs. control follow-up, control baseline vs. ALS baseline, control follow-up vs. ALS follow-up, and ALS baseline vs. ALS follow-up. Results: The mean time from the diagnosis was 10.80 ± 5.5 months. The analysis of the optical coherence tomography (OCT) showed: (1) In ALS baseline vs. control baseline, a macular significantly increased thickness of the inner macular ring temporal and inferior areas; (2) in ALS follow-up vs. ALS baseline, a significant macular thinning in the inner and outer macular ring inferior areas; (3) in ALS follow-up vs. ALS baseline, a significant peripapillary retinal nerve fiber layer (pRNFL) thinning in the superior and inferior quadrants; and (4) ALS patients showed a moderate correlation between some OCT pRNFL parameters and Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) score. Conclusion: The OCT showed retinal changes in patients with motoneuron disease and could serve as a complementary tool for studying ALS.
Changes in visual function and retinal structure in the progression of Alzheimer's disease
(Public Library Science, 2019-08-15) García Martín, Elena Salobrar; Hoz Montañana, Rosa de; Ramírez Sebastián, Ana Isabel; López Cuenca, Inés; Rojas Lozano, Pilar; Vazirani Ballesteros, Ravi; Amarante Cuadrado, Carla; Yubero Pancorbo, Raquel; Gil Gregorio, Pedro; Pinazo Durán, Mª Dolores; Salazar Corral, Juan José; Ramirez Sebastian, Jose Manuel
Background: Alzheimer’s Disease (AD) can cause degeneration in the retina and optic nerve either directly, as a result of amyloid beta deposits, or secondarily, as a result of the degradation of the visual cortex. These effects raise the possibility that tracking ophthalmologic changes in the retina can be used to assess neurodegeneration in AD. This study aimed to detect retinal changes and associated functional changes in three groups of patients consisting of AD patients with mild disease, AD patients with moderate disease and healthy controls by using non-invasive psychophysical ophthalmological tests and optical coherence tomography (OCT). Methods: We included 39 patients with mild AD, 21 patients with moderate AD and 40 age-matched healthy controls. Both patients and controls were ophthalmologically healthy. Visual acuity, contrast sensitivity, colour perception, visual integration, and choroidal thicknesses were measured. In addition, OCT and OCT angiography (OCTA) were applied. Findings: Visual acuity, contrast sensitivity, colour perception, and visual integration were significantly lower in AD patients than in healthy controls. Compared to healthy controls, macular thinning in the central region was significant in the mild AD patients, while macular thickening in the central region was found in the moderate AD group. The analysis of macular layers revealed significant thinning of the retinal nerve fibre layer, the ganglion cell layer and the outer plexiform layer in AD patients relative to controls. Conversely, significant thickening was observed in the outer nuclear layer of the patients. However, mild AD was associated with significant thinning of the subfovea and the nasal and inferior sectors of the choroid. Significant superonasal and inferotemporal peripapillary thinning was observed in patients with moderate disease. Conclusions: The first changes in the mild AD patients appear in the psychophysical tests and in the central macula with a decrease in the central retinal thickness. When there was a disease progression to moderate AD, psychophysical tests remained stable with respect to the decrease in mild AD, but significant thinning in the peripapillary retina and thickening in the central retina appeared. The presence of AD is best indicated based on contrast sensitivity.
Characterization of Retinal Drusen in Subjects at High Genetic Risk of Developing Sporadic Alzheimer’s Disease: An Exploratory Analysis
(MDPI, 2022-05-23) López Cuenca, Inés; García Martín, Elena Salobrar; Gil Salgado, Inés; Sánchez Puebla, Lídia; Elvira Hurtado, Lorena; Fernández Albarral, José Antonio; Ramírez Toraño, Federico; Barabash, Ana; Frutos Lucas, Jaisalmer de; Salazar Corral, Juan José; Ramirez Sebastian, Jose Manuel; Ramírez Sebastián, Ana Isabel; Hoz Montañana, María Rosa de
Having a family history (FH+) of Alzheimer’s disease (AD) and being a carrier of at least one ɛ4 allele of the ApoE gene are two of the main risk factors for the development of AD. AD and age-related macular degeneration (AMD) share one of the main risk factors, such as age, and characteristics including the presence of deposits (Aβ plaques in AD and drusen in AMD); however, the role of apolipoprotein E isoforms in both pathologies is controversial. We analyzed and characterized retinal drusen by optical coherence tomography (OCT) in subjects, classifying them by their AD FH (FH- or FH+) and their allelic characterization of ApoE ɛ4 (ApoE ɛ4- or ApoE ɛ4+) and considering cardiovascular risk factors (hypercholesterolemia, hypertension, and diabetes mellitus). In addition, we analyzed the choroidal thickness by OCT and the area of the foveal avascular zone with OCTA. We did not find a relationship between a family history of AD or any of the ApoE isoforms and the presence or absence of drusen. Subjects with drusen show choroidal thinning compared to patients without drusen, and thinning could trigger changes in choroidal perfusion that may give rise to the deposits that generate drusen
Comparision of intraocular pressure measured using the new icare 200™ rebound tonometer and the Perkins™ applanation tonometer in healthy subjects and in patients with primary congenital glaucoma
(Elsevier, 2021-04) Pérez García, Pilar; Morales Fernández, Laura; Sáenz Francés, Federico; Méndez Hernández, Carmen Dora; García Feijoo, Julián; Santos Bueso, Enrique; Martínez de la Casa, José María
Objective: To compare intraocular pressure (IOP) measurements obtained using the Icare 200™ (IC200) rebound tonometer and the hand-held version of the Goldmann Applanation Tonometer (Perkins™ tonometer, GAT) in patients with primary congenital glaucoma (PCG) and in healthy subjects. Material and methods: A total of 42 eyes of healthy subjects (G1) and 40 patients with PCG (G2) were analysed. The following clinical data were collected: gender, age, Cup/Disc ratio, central corneal thickness (CCT). IOP was determined in the examination room using the IC200 and GAT tonometers, in the same order. Agreement between both tonometers was determined using the intraclass correlation coefficient (ICC) and Bland-Altman plot. A linear regression analysis was used to establish the IOP was affected by the studied variables. Results: Mean IOP between both tonometers (IC200 minus GAT) was: G1 = 15.91 (2.57) mmHg vs. 15.06 (2.12) mmHg (mean difference, MD = 0.84 (0.50) mmHg; P < .101) and G2=20.10 (6.37) vs.19.12 (5.62) (MD = 0.98 (1.36); P = 0.474). Excellent agreement was found between IC200 and GAT in both groups (ICC = G1: 0.875 (95% CI; 0.768−0.933; P < .001); G2: 0.924 (95% CI; 0.852−0.961; P < .001), and there was a statistically significant correlation between the IOP difference measured with IC200 and GAT and CCT in G1 (B=0.021; 95% CI; 0.005–0.037; P = .008), but was not statistically significant in G2. Conclusions: There was excellent agreement between the IC200 and GAT tonometers, both in healthy subjects and PCG, with a trend to overestimate IOP when measured with IC200. There was no influence by CCT on IOP measurements in patients with PGC.
Comparison and evaluation of local and connected fractal dimension to analyze the retinal images
(OSA Publishing, 2020) Igalla El Youssfi, Asmae; López Alonso, José Manuel
The analysis of the fractal dimension (FD) of the retinas using the methods for measuring local (LFD) and connected (Dlc) DF in images of healthy retinas establishes a similar behavior with slightly differences.
Contact lens fitting through assessment of tear film affectation with different designs by means of thermal camera
(OSA Publishing, 2020) Durán Prieto, Elena; López Alonso, José Manuel
The study of contact lenses fitting of different designs through the impact on the tear through infrared images of the eye has been carried out. Multifocal lens design behaves as well as traditional ones.
Corneal Confocal Microscopy Findings in Neuro Lyme Disease: A Case Report
(MDPI, 2022-01-29) Cañadas Suárez, Pilar; García González, Montserrat; Cañones Zafra, Rafael; Teus Guezala, Miguel Ángel
Neuro Lyme disease is caused by several bacteriae of the Borreliaceae family, such as Borrelia Miyamotoi. In late stages of illness, patients with Lyme disease may develop chronic neurologic symptoms such as cognitive disturbances or small fiber peripheral neuropathy. Confocal microscopy is a non-invasive method designed to evaluate the human cornea in vivo. Thus, all the corneal layers, including the cells and the sub-basal nerve plexus, can be easily visualized and analyzed. This is the first report of the morphology of small-fiber peripheral neuropathy analyzed by confocal microscopy in a patient diagnosed of neuro Lyme disease. The decrease in the number of unmyelinated sub-basal nerve fibers with abundant presence of dendritic cells (DC) in comparison with healthy corneas strongly supports the diagnosis of small fiber peripheral neuropathy in a case of neuroborreliosis disease.
Corneal densitometry and biomechanical properties in patients with primary congenital glaucoma
(Canadian Ophthalmology Society; Elsevier, 2021-02-10) Morales Fernández, Laura; Benito Pascual, Blanca; Pérez García, Pilar; Perucho González, Lucía; Sáenz Francés, Federico; Santos Bueso, Enrique; García Bella, Javier; Sánchez Jean, Rubén; García Feijoo, Julián; Martínez de la Casa, Jose Maria
Objective: To describe corneal densitometry, topographic measurements, and biomechanical properties in patients with primary congenital glaucoma (PCG) and healthy patients. To examine correlations between variables and determine their glaucoma diagnostic capacity. Methods: This was a cross-sectional, case-control study conducted in 50 eyes of 50 patients with PCG (G1) and 40 eyes of 40 healthy patients (G2). The variables determined in each participant were: intraocular pressure, best corrected visual acuity (BCVA), corneal densitometry, topographic data using the Pentacam HR-Scheimpflug imaging system (Oculus Optikgerate GmbH, Wetzlar, Germany), and corneal hysteresis (CH) and corneal resistance factor (CRF) using the Ocular Response Analyzer (Reichert Ophthalmic Instruments, Depew, NY). Results: Overall densitometry was significatively higher in the PCG group (G1: 17.94 ± 4.99 vs G2: 13.25 ± 1.96, p < 0.001). CH (G1: 8.02 ± 11.35 vs G2: 11.35 ± 1.42, p < 0.001) and CRF (G1: 9.48 ± 2.83 vs G2: 10.77 ± 1.34, p < 0.001) were lower in the glaucoma group. Mean posterior, central, and anterior elevation and mean keratometry were higher in G1 (p < 0.05). In the PCG group, overall densitometry showed significant correlation with CH (r = –0.321, p = 0.028) and with BCVA (r = −0.498, p = 0.002). AUCs (areas under the curve) for CH and overall densitometry were high (0.839 and 0.899 respectively) and the best overall densitometry; CH and CRF cutoffs were 14.0, 9.3 and 9.2 respectively. Conclusion: Densitometry is increased, and biomechanical corneal properties are decreased in patients with PCG. Densitometry and visual acuity showed a negative and significant correlation, so this measurement could be used as an indirect parameter of BCVA in the clinical practice.
Corneal Properties in Primary Open Angle Glaucoma Assessed Through Scheimpflug Corneal Topography and Densitometry
(Wolters Kluwer Health, 2020-12-10) Molero Senosiain, Mercedes; Morales Fernández, Laura; Sáenz Francés, Federico; Perucho González, Lucía; García Bella, Javier; García Feijoo, Julián; Martínez de la Casa, Jose Maria
Purpose: To compare corneal topography and densitometry measurements in patients with primary open angle glaucoma (POAG) and healthy subjects. Patients and Methods: 200 eyes of 75 patients with POAG and 125 healthy controls underwent corneal topography and densitometry (Oculus Pentacam HR). The data compared in the two groups were: anterior chamber angle (ACA), depth (ACD) and volume (ACV), keratometry (K minimum, K maximum and K mean), central corneal thickness (CCT), central anterior elevation (CAE), anterior elevation apex (AEA), maximum anterior elevation (MAE) and posterior elevation apex (PEA). Densitometry measurements were made at three depths on a 12▒mm-diameter circle divided into 4 concentric rings (0-2▒mm, 2-6▒mm, 6-10▒mm and 10-12▒mm). The diagnostic capacity of the corneal variables was assessed through the areas under the receiver operator characteristics (ROC) curve (AUC). Results: The corneal density of practically all depth layers and total corneal density were significantly higher in the POAG than control group (P<0.05). Total corneal density was positively correlated with age (r=0.623; P<0.001) and also showed a good diagnostic capacity for glaucoma (AUC=0.617; IC 95% [0.541-0.697]; P<0.001). In a multiple linear regression designed to assess its relationship with age, gender, CCT and Km, age emerged as a significant confounder both in controls (coef. 0.315; P<0.001; 95% CI [0.246-0.384]) and patients (coef. 0.370; P<0.001; 95% CI [0.255-0.486]). Conclusion: Corneal densitometry measurements showed a good diagnostic capacity for POAG suggesting this type of examination could have clinical applications in the diagnosis and management of glaucoma.

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