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4.
Phys Rev Lett ; 130(6): 061002, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36827578

RESUMO

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28} cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25} cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

5.
Arch. Soc. Esp. Oftalmol ; 98(2): 98-104, feb. 2023. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-215177

RESUMO

Objetivos Analizar la situación actual de la cirugía refractiva con implante de lente fáquica Visian ICL en España, señalando los rangos medios de potencias implantadas, los resultados visuales y refractivos obtenidos y los índices de seguridad y eficacia. Método Se trata de un estudio de población, transversal, descriptivo, analítico, retrospectivo, multicéntrico, en el que cada coautor recopiló los datos de, al menos, los 10 últimos pacientes (hasta un máximo de 30) con implante de lente fáquica Visian ICL. Se eligió aleatoriamente un ojo de cada sujeto para incluirlo en el estudio, y se analizaron las variables: edad, género, agudezas visuales sin corrección y con corrección pre y posquirúrgica, refracción preoperatoria y residual, queratometrías, recuento endotelial, profundidad de cámara anterior desde endotelio, paquimetría corneal central, presión intraocular, distancia blanco-blanco, lente implantada (potencia y talla) y equivalente esférico (SEQ) esperado y obtenido posquirúrgico al mes de la cirugía. Resultados Se obtuvo una muestra de 140 ojos de 140 pacientes con una edad media de 31,35±7,28 años. El SEQ preoperatorio medio fue de −6,33±3,69, la agudeza visual con corrección media de 0,96±0,16, la profundidad de cámara anterior desde endotelio de 3,30±0,29mm, distancia blanco-blanco 12,02±0,40mm, paquimetría corneal central 535,03±37,68μm, recuento endotelial 2.684,37±313,74céls/mm2 y presión intraocular 14,84±2,59mmHg. El 66,4% de las lentes implantadas fueron ICL esféricas y el 33,6% tóricas, con una potencia media de −7,81±4,09D y un cilindro medio de 2,27±1,23D. El 5,7% fueron hipermetrópicas. El 45,69% de las lentes implantadas eran de la talla 13,2mm, siendo el 37,93, 12,93 y 3,45% restante de las tallas 12,6, 12,1 y 13,7mm, respectivamente. Al mes de la cirugía se obtuvo un SEQ residual de −0,01±0,31D. Los índices de eficacia y seguridad fueron de 1,06±0,18 y 1,10±0,19, respectivamente... (AU)


Objectives To analyse the state of refractive surgery with Visian ICL phakic lens implantation in Spain, indicating the mean ranges of implanted powers, visual and refractive outcomes obtained and safety and efficacy indices. Method This is a population-based, cross-sectional, descriptive, analytical, retrospective, multicentre study in which each co-author collected data from at least the last 10 patients (up to a maximum of 30) with Visian ICL phakic lens implantation. One eye from each subject was randomly selected for study inclusion, and the variables analysed were: age, gender, visual acuities with and without correction pre and post-surgery, preoperative and residual refraction, keratometry, endothelial cellular density, anterior chamber depth from endothelium, central corneal pachymetry, intraocular pressure, white-white, implanted lens (power and size), expected and achieved spherical equivalent (SEQ) post-surgery at one month after surgery. Results A sample of 140 eyes was obtained from 140 patients with a mean age of 31.35±7.28 years. Mean preoperative SEQ was −6.33±3.69D, mean visual acuities with correction was 0.96±0.16, anterior chamber depth was 3.30±0.29mm, white-white 12.02±0.40mm, central corneal pachymetry 535.03±37.68μm, endothelial cellular density 2684.37±313.74cels/mm2 and intraocular pressure 14.84±2.59mmHg. A percentage of 66.4 of the implanted lenses were spherical ICLs and 33.6% toric, with a mean power of −7.81±4.09D and a mean cylinder of 2.27±1.23D. A percentage of 5.7 of the implanted lenses were hypermetropic. The mean SEQ target selected was +0.04±0.27D. A percentage of 45.69 of the implanted lenses were of size 13.2mm, with the remaining 37.93, 12.93 and 3.45% being of sizes 12.6, 12.1 and 13.7mm, respectively. At one month after surgery a residual SEQ of −0.01±0.31D was obtained. The efficacy and safety indices were 1.06±0.18 and 1.10±0.19...(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Refrativos , Lentes Intraoculares Fácicas , Miopia/cirurgia , Estudos Transversais , Estudos Retrospectivos , Segurança , Eficácia
6.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(2): 98-104, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36115821

RESUMO

OBJECTIVES: To analyse the state of refractive surgery with Visian ICL phakic lens implantation in Spain, indicating the mean ranges of implanted powers, visual and refractive outcomes obtained and safety and efficacy indices. METHOD: This is a population-based, cross-sectional, descriptive, analytical, retrospective, multicentre study in which each co-author collected data from at least the last 10 patients (up to a maximum of 30) with Visian ICL phakic lens implantation. One eye from each subject was randomly selected for study inclusion, and the variables analysed were: age, gender, visual acuities with and without correction pre and post-surgery, preoperative and residualrefraction, keratometry, endothelial cellular density, anterior chamber depth from endothelium, central corneal pachymetry, intraocular pressure, white-white, implanted lens (power and size), expected and achieved spherical equivalent (SEQ) post-surgery at one month after surgery. RESULTS: A sample of 140 eyes was obtained from 140 patients with a mean age of 31.35 ± 7.28 years. Mean preoperative SEQ was -6.33 ± 3.69D, mean CDVA was 0.96 ± 0.16, ACD was 3.30 ± 0.29 mm, WTW 12.02 ± 0.40 mm, CCT 535.03 ± 37.68 µm, ECD 2684.37 ± 313.74 cels/mm2 and IOP 14.84 ± 2.59 mmHg. 66.4% of the implanted lenses were spherical ICLs and 33.6% toric, with a mean power of -7.81 ± 4.09D and a mean cylinder of 2.27 ± 1.23D. 5.7% of the implanted lenses were hypermetropic. The mean SEQ target selected was +0.04 ± 0.27D. 48.92% of the implanted lenses were of size 13.2 mm, with the remaining 36.69, 10.79 and 3.60% being of sizes 12.6, 12.1 and 13.7 mm, respectively. At one month after surgery a residual SEQ of -0.01 ± 0.31D was obtained. The efficacy and safety indices were 1.06 ± 0.18 and 1.10 ± 0.19, respectively. The mean central vault was 508.80 ± 201.04 µm. The accuracy between the calculated SEQ and the obtained SEQ was 99.3% for spherical lenses and 88.2% for Cyl correction. The mean ECD at 1 month after surgery was 2805.53±273.30céls/mm2, which was a difference from preoperative of 0.11% (p = 0.922), similarly, the mean IOP was 13.98 ± 2.57 mmHg, which was a difference of -0.92 ± 2.80 mmHg. CONCLUSIONS: ICL phakic lens surgery is an effective, safe and predictable procedure. There were no significant changes in endothelial cell count or intraocular pressure measurement one month after surgery.


Assuntos
Miopia , Lentes Intraoculares Fácicas , Humanos , Adulto Jovem , Adulto , Estudos Retrospectivos , Espanha , Estudos Transversais , Miopia/cirurgia , Implante de Lente Intraocular
8.
Phys Med Biol ; 67(24)2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36384047

RESUMO

Objective. The goal of this work is to experimentally compare the 3D spatial and energy resolution of a semi-monolithic detector suitable for total-body positron emission tomography (TB-PET) scanners using different surface crystal treatments and silicon photomultiplier (SiPM) models.Approach. An array of 1 × 8 lutetium yttrium oxyorthosilicate (LYSO) slabs of 25.8 × 3.1 × 20 mm3separated with Enhanced Specular Reflector (ESR) was coupled to an array of 8 × 8 SiPMs. Three different treatments for the crystal were evaluated: ESR + RR + B,with lateral faces black (B) painted and a retroreflector (RR) layer added to the top face; ESR +RR, with lateral faces covered with ESR and a RR layer on the top face and; All ESR, with lateral and top sides with ESR. Additionally, two SiPM array models from Hamamatsu Photonics belonging to the series S13361-3050AE-08 (S13) and S14161-3050AS-08 (S14) have been compared. Coincidence data was experimentally acquired using a22Na point source, a pinhole collimator, a reference detector and moving the detector under study in 1 mm steps in thex- andDOI- directions. The spatial performance was evaluated by implementing a neural network (NN) technique for the impact position estimation in thex- (monolithic) andDOIdirections.Results. Energy resolution values of 16 ± 1%, 11 ± 1%, 16 ± 1%, 15 ± 1%, and 13 ± 1% were obtained for theS13-ESR + B + RR,S13-AllESR,S14-ESR + B + RR,S14-ESR + RR,andS14-AllESR, respectively. Regarding positioning accuracy, mean average error of 1.1 ± 0.5, 1.3 ± 0.5 and 1.3 ± 0.5 were estimated for thex- direction and 1.7 ± 0.8, 2.0 ± 0.9 and 2.2 ± 1.0 for theDOI- direction, for the ESR + B + RR, ESR + RR and All ESR cases, respectively, regardless of the SiPM model.Significance. Overall, the obtained results show that the proposed semi-monolithic detectors are good candidates for building TB-PET scanners.


Assuntos
Redes Neurais de Computação , Tomografia por Emissão de Pósitrons
9.
Arch. Soc. Esp. Oftalmol ; 97(9): 490-496, sept. 2022. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-209102

RESUMO

Objetivo Investigar la eficacia y la seguridad del protocolo de luz pulsada intensa (IPL) combinando el protocolo de tratamiento con IPL para la disfunción de las glándulas de Meibomio/enfermedad de ojo seco con IPL aplicada directamente en los párpados, asociada a la expresión de las glándulas de Meibomio (GM) para el tratamiento del chalación. Material y métodos Estudio retrospectivo de serie de casos. Los pacientes que presentaron chalación, recibieron un tratamiento combinado de terapia con IPL que consistió en usar el protocolo habitual de IPL para disfunción de las glándulas de Meibomio/enfermedad de ojo seco empleando una fluencia de acuerdo al tipo de piel según Fitzpatrick, seguido de una segunda fase (en la misma sesión) de aplicación IPL directamente sobre los párpados de ambos ojos empleando una fluencia de 10J/cm2. A continuación, todos los pacientes recibieron expresión de las GM, higiene de los párpados, antibiótico tópico y medicación ocular antiinflamatoria tópica. Los efectos adversos relacionados con este protocolo se evaluaron en cada sesión de IPL. Resultados Se incluyeron 26 chalaciones de diecinueve pacientes (24 ojos) con una edad media de 49,89±20,43 años. Fueron necesarias 2,07±0,97 sesiones de IPL de media para la resolución del chalación. El tratamiento combinado de protocolo IPL y expresión de GM mostró un 96,15% de eficacia y no se observaron efectos adversos. Conclusiones El tratamiento combinado de IPL para disfunción de las glándulas de Meibomio/enfermedad de ojo seco con IPL aplicado directamente sobre los párpados y expresión de GM podría ser eficaz y seguro para el tratamiento de los chalaciones (AU)


Objective To investigate the efficacy and safety of an intense pulsed light (IPL) combined IPL treatment protocol for meibomian gland dysfunction (MGD)/dry eye disease (DED) with IPL applied directly to the eyelids, associated with meibomian gland (MG) expression for the treatment of chalazion. Material and Methods Retrospective case series study. Patients presenting with chalazion received a combined IPL therapy treatment consisting of using the usual IPL protocol for DGM/EOS using a fluence according to skin type according to Fitzpatrick, followed by a second phase (in the same session) of IPL application directly on the eyelids of both eyes using a fluence of 10 J/cm2. All patients then received GM expression, eyelid hygiene, topical antibiotic and topical ocular anti-inflammatory medication. Adverse effects related to this protocol were assessed at each IPL session. Results Twenty-six chalazions from nineteen patients (24 eyes) with a mean age of 49.89 ± 20.43 years were included. An average of 2.07 ± 0.97 IPL sessions were required for chalazion resolution. The combined treatment of IPL protocol and GM expression showed 96.15% efficacy and no adverse effects were observed. Conclusions Combined IPL treatment for DGM/EOS with IPL applied directly on the eyelids and GM expression could be effective and safe for the treatment of chalazions (AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Calázio/terapia , Síndromes do Olho Seco/terapia , Glândulas Tarsais/fisiopatologia , Terapia de Luz Pulsada Intensa , Resultado do Tratamento , Estudos Retrospectivos , Terapia Combinada , Protocolos Clínicos
10.
Arch Soc Esp Oftalmol (Engl Ed) ; 97(9): 490-496, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35787379

RESUMO

OBJECTIVE: To investigate the efficacy and safety of an intense pulsed light (IPL) combined IPL treatment protocol for meibomian gland dysfunction (MGD)/dry eye disease (DED) with IPL applied directly to the eyelids, associated with meibomian gland (MG) expression for the treatment of chalazion. MATERIAL AND METHODS: Retrospective case series study. Patients presenting with chalazion received a combined IPL therapy treatment consisting of using the usual IPL protocol for DGM/EOS using a fluence according to skin type according to Fitzpatrick, followed by a second phase (in the same session) of IPL application directly on the eyelids of both eyes using a fluence of 10J/cm2. All patients then received GM expression, eyelid hygiene, topical antibiotic and topical ocular anti-inflammatory medication. Adverse effects related to this protocol were assessed at each IPL session. RESULTS: Twenty-six chalazions from nineteen patients (24 eyes) with a mean age of 49.89±20.43 years were included. An average of 2.07±0.97 IPL sessions were required for chalazion resolution. The combined treatment of IPL protocol and GM expression showed 96.15% efficacy and no adverse effects were observed. CONCLUSIONS: Combined IPL treatment for MGD/DED with IPL applied directly onto the eyelids and MGX could be effective and safe for the management of chalazions.


Assuntos
Calázio , Síndromes do Olho Seco , Disfunção da Glândula Tarsal , Adulto , Idoso , Calázio/terapia , Síndromes do Olho Seco/terapia , Humanos , Disfunção da Glândula Tarsal/terapia , Glândulas Tarsais , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Asia Pac J Ophthalmol (Phila) ; 9(6): 571-579, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33181549

RESUMO

Corneal grafting is one of the most common forms of human tissue transplantation. The corneal stroma is responsible for many characteristics of the cornea. For these reasons, an important volume of research has been made to replicate the corneal stroma in the laboratory to find an alternative to classical corneal transplantation techniques.There is an increasing interest today in cell therapy of the corneal stroma using induced pluripotent stem cells or mesenchymal stem cells since these cells have shown to be capable of producing new collagen within the host stroma and even to improve its transparency.The first clinical experiment on corneal stroma regeneration in advanced keratoconus cases has been reported and included. Fourteen patients were randomized and enrolled into 3 experimental groups: (1) patients underwent implantation of autologous adipose-derived adult stem cells alone, (2) patients received decellularized donor corneal stroma laminas, and (3) patients received implantation of recellularized donor laminas with adipose-derived adult stem cells. Clinical improvement was detected with all cases in their visual, pachymetric, and topographic parameters of the operated corneas.Other recent studies have used allogenic SMILE implantation lenticule corneal inlays, showing also an improvement in different visual, topographic, and keratometric parameters.In the present report, we try to summarize the available preclinical and clinical evidence about the emerging topic of corneal stroma regeneration.


Assuntos
Substância Própria/patologia , Transplante de Córnea/métodos , Ceratocone/cirurgia , Acuidade Visual , Substância Própria/cirurgia , Topografia da Córnea , Humanos , Ceratocone/diagnóstico , Tomografia de Coerência Óptica
13.
Phys Med Biol ; 65(24): 245027, 2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33120374

RESUMO

The IRIS group at IFIC Valencia is developing a three-layer Compton camera for treatment monitoring in proton therapy. The system is composed of three detector planes, each made of a [Formula: see text] monolithic crystal coupled to a SiPM array. Having obtained successful results with the first prototype (MACACO) that demonstrated the feasibility of the proposed technology, a second prototype (MACACO II) with improved performance has been developed, and is the subject of this work. The new system has an enhanced detector energy resolution which translates into a higher spatial resolution of the telescope. The image reconstruction method has also been improved with an accurate model of the sensitivity matrix. The device has been tested with high energy photons at the National Accelerator Centre (CNA, Seville). The tests involved a proton beam of 18 MeV impinging on a graphite target, to produce 4.4 MeV photons. Data were taken at different system positions of the telescope with the first detector at 65 and 160 mm from the target, and at different beam intensities. The measurements allowed successful reconstruction of the photon emission distribution at two target positions separated by 5 mm in different telescope configurations. This result was obtained both with data recorded in the first and second telescope planes (two interaction events) and, for the first time in beam experiments, with data recorded in the three planes (three interaction events).


Assuntos
Fótons , Terapia com Prótons/métodos , Estudos de Viabilidade , Humanos , Terapia com Prótons/instrumentação , Telescópios
14.
Rev Esp Anestesiol Reanim (Engl Ed) ; 67(8): 446-480, 2020 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32948329

RESUMO

Transesophageal echocardiography is a semi-invasive technique that allows an evaluation of cardiac morphology and function in real time and it is a quality standard in cardiovascular surgery. It has become a fundamental tool for both monitoring and diagnosis in the intraoperative period that allows decide the correct surgical planning and pharmacological management. The goal of this document is to answer the questions of when and how the perioperative TEE should be performed in cardiovascular surgery, what are their applications in the intraoperative, who should perform it and how the information should be transmitted. The authors made a systematic review of international guidelines, review articles and clinical trials to answer by consensus to these questions.

15.
Phys Rev Lett ; 125(2): 021301, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32701326

RESUMO

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.

16.
Arch Soc Esp Oftalmol (Engl Ed) ; 95(6): 300-310, 2020 Jun.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32409243

RESUMO

OBJECTIVE: Minimize exposure to the SARS-CoV-2, reduce the chances of cross-transmission between patients and healthcare personnel, and prevent the development of postoperative complications from the management of patients with eye diseases during the 2019 coronavirus disease pandemic (COVID-19). METHODS: COVID-19 literature review and consensus establishment between different Spanish ophthalmology societies in order to provide guidelines and recommendations of maximum resources primarily conditioned by the state of alert, confinement and social distancing that occurs in Spain since March 16, 2020. RESULTS: The recommendations will promote the adoption of action and protection measures for eye care in outpatient clinics, surgical areas and hospitalization, for unconfirmed (asymptomatic and symptomatic) and confirmed COVID-19 patients. Measures must be adapted to the circumstances and availability of personal protective equipment in each of the centers and Autonomous Communities, which will be updated according to the pandemic phases and the measures adopted by the Spanish Government. CONCLUSIONS: During the COVID-19 pandemic, attention to the potential health risks to the population caused by coronavirus should prevail over the possible progression of the common eye diseases. Ophthalmologists and other eye care professionals must assume a possible progression of these diseases due to the impossibility of adequate patient follow-up.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Oftalmopatias/diagnóstico , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Complicações Pós-Operatórias/prevenção & controle , Antimaláricos/uso terapêutico , Doenças Assintomáticas , Segurança do Sangue , COVID-19 , Cloroquina/uso terapêutico , Lentes de Contato , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/prevenção & controle , Progressão da Doença , Oftalmopatias/terapia , Humanos , Hidroxicloroquina/uso terapêutico , Procedimentos Cirúrgicos Oftalmológicos/efeitos adversos , Procedimentos Cirúrgicos Oftalmológicos/métodos , Oftalmologia , Pandemias/prevenção & controle , Pneumonia Viral/diagnóstico , Pneumonia Viral/prevenção & controle , Fatores de Risco , SARS-CoV-2 , Sociedades Médicas , Espanha , Avaliação de Sintomas/métodos , Suspensão de Tratamento
17.
Phys Med Biol ; 65(14): 145005, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32330911

RESUMO

Compton Cameras are electronically collimated photon imagers suitable for sub-MeV to few MeV gamma-ray detection. Such features are desirable to enable in vivo range verification in hadron therapy, through the detection of secondary Prompt Gammas. A major concern with this technique is the poor image quality obtained when the incoming gamma-ray energy is unknown. Compton Cameras with more than two detector planes (multi-layer Compton Cameras) have been proposed as a solution, given that these devices incorporate more signal sequences of interactions to the conventional two interaction events. In particular, three interaction events convey more spectral information as they allow inferring directly the incident gamma-ray energy. A three-layer Compton Telescope based on continuous Lanthanum (III) Bromide crystals coupled to Silicon Photomultipliers is being developed at the IRIS group of IFIC-Valencia. In a previous work we proposed a spectral reconstruction algorithm for two interaction events based on an analytical model for the formation of the signal. To fully exploit the capabilities of our prototype, we present here an extension of the model for three interaction events. Analytical expressions of the sensitivity and the System Matrix are derived and validated against Monte Carlo simulations. Implemented in a List Mode Maximum Likelihood Expectation Maximization algorithm, the proposed model allows us to obtain four-dimensional (energy and position) images by using exclusively three interaction events. We are able to recover the correct spectrum and spatial distribution of gamma-ray sources when ideal data are employed. However, the uncertainties associated to experimental measurements result in a degradation when real data from complex structures are employed. Incorrect estimation of the incident gamma-ray interaction positions, and missing deposited energy associated with escaping secondaries, have been identified as the causes of such degradation by means of a detailed Monte Carlo study. As expected, our current experimental resolution and efficiency to three interaction events prevents us from correctly recovering complex structures of radioactive sources. However, given the better spectral information conveyed by three interaction events, we expect an improvement of the image quality of conventional Compton imaging when including such events. In this regard, future development includes the incorporation of the model assessed in this work to the two interaction events model in order to allow using simultaneously two and three interaction events in the image reconstruction.


Assuntos
Raios gama , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Humanos , Método de Monte Carlo , Probabilidade , Cintilografia , Espalhamento de Radiação
18.
Eye (Lond) ; 34(9): 1570-1576, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31723247

RESUMO

PURPOSE: To study the relationship between macular ganglion cell complex (GCC) thickness and visual field defects (VFD) caused by central nervous system (CNS) lesions in children and evaluate the possibility of predicting VFD according to GCC maps. METHODS: The GCC maps of a group of children with VFD due to CNS lesions with respect of the vertical meridian in at least one eye (study group), as well as of children with other neuro-ophthalmological problems and healthy children were presented to two masked evaluators, who were asked to predict the patients' VFD on the basis of GCC damage: the evaluators classified VFD as normal, hemianopia (homonymous or heteronymous) or diffuse. RESULTS: Seventeen patients were included in the study group, with a median age of 12 years. Fifteen had brain tumours and two epilepsy. The mean MD of the affected hemifields was -26.00 dB (SD 7.89 dB) versus -5.51 dB (SD 3.52 dB) for the nonaffected hemifields, p < 0.001. The mean GCC thickness was of 56.04 µm (SD 11.95 µm) in the affected hemiretinas versus 74.31 µm (SD 10.64 µm) for the non-affected, p < 0.001. Kappa coefficients between VFD and those estimated by the evaluators were 0.705 and 0.658 (p < 0.001) for evaluators 1 and 2. CONCLUSIONS: GCC thickness can reflect damage to the visual pathway and GCC maps may be useful to identify chiasmal and retrochiasmal lesions, since GCC atrophy in most of these cases respects the vertical meridian. GCC maps might be used as a surrogate marker for visual damage in patients unable to perform perimetry.


Assuntos
Testes de Campo Visual , Campos Visuais , Sistema Nervoso Central , Criança , Humanos , Células Ganglionares da Retina , Tomografia de Coerência Óptica
19.
J Ophthalmol ; 2019: 8731626, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31662899

RESUMO

Assessing changes suffered by the cornea as keratoconus progresses has proven to be vital for this disease diagnosis and treatment. This study determines the corneal biometric profile in eyes considered as affected by keratoconus (KC) showing severe visual limitation, by means of in vivo 3D modelling techniques. This observational case series study evaluated new objective indices in 50 healthy and 30 KC corneas, following a validated protocol created by our research group, which has been previously used for diagnosis and characterization of KC in asymptomatic (preclinical) and mild visually impaired eyes. Results show a statistically significant reduction of corneal volume and an increase of total corneal area in the severe KC group, being anterior and posterior corneal surfaces minimum thickness points the best correlated parameters, although with no discrimination between groups. Receiving operator curves were used to determine sensitivity and specificity of selected indices, being anterior and posterior apex deviations the ones which reached the highest area under the curve, both with very high sensitivity (96.7% and 90%, respectively) and specificity (94.0% and 99.9%, respectively). The results suggest that once severe visual loss appears, anterior corneal topography should be considered for a more accurate diagnosis of clinical KC, being anterior apex deviation the key metric discriminant. This study can be a useful tool for KC classification, helping doctors in diagnosing severe cases of the disease, and can help to characterize corneal changes that appear when severe KC is developed and how they relate with vision deterioration.

20.
Rev Esp Anestesiol Reanim (Engl Ed) ; 66(10): 528-532, 2019 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31587921

RESUMO

Despite the widespread and frequent use in our setting of pulmonary artery catheters for haemodynamic management in critically ill patients, particularly after heart surgery, some experts continue to question the need for these devices. Clinicians need to weigh up the risks and benefits of pulmonary artery catheters placement and bear in mind the potential complications which, though rare, can be potentially fatal. We present a pulmonary artery catheters-related complication not hitherto described in the literature, involving perforation of the interventricular septum and left ventricular free wall caused by a kink in the pulmonary artery catheters that was not suspected, and only diagnosed by direct vision of the heart after pericardial opening. In the interest of patient safety, we must consider the impact of adverse events; improving our situational awareness and our understanding of the mechanisms behind such events can help reduce the likelihood of repetitions in the future.


Assuntos
Cateterismo de Swan-Ganz/efeitos adversos , Traumatismos Cardíacos/etiologia , Ventrículos do Coração/lesões , Complicações Intraoperatórias/etiologia , Idoso , Aneurisma Aórtico/cirurgia , Cateterismo de Swan-Ganz/instrumentação , Ecocardiografia/métodos , Falha de Equipamento , Feminino , Septos Cardíacos/lesões , Humanos , Artéria Pulmonar/diagnóstico por imagem
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