Une hémorragie prérétinienne peut compliquer plusieurs pathologies parmi lesquelles la rétinopathie de Valsalva. Elle peut être à l’origine de troubles visuels symptomatiques qui amènent le patient à ...consulter en urgence. Nous rapportons le cas d’une patiente âgée de 39 ans, sans antécédents pathologiques particuliers, a consulté pour une baisse brutale de l’acuité visuelle de l’œil droit. Cette symptomatologie est apparue quelques minutes après un effort de défécation suite à une constipation. L’examen ophtalmologique a trouvé au niveau de l’œil droit, une acuité visuelle corrigée chiffrée à comptes les doigts de près. Le fond d’œil a révélé une hémorragie maculaire suspendue en nid de pigeon. Le diagnostic d’hémorragie rétro-hyaloïdienne droite spontanée secondaire à une hyperpression veineuse céphalique a été retenu. Une membranotomie au laser Yag a été réalisé à distance de la fovéa. L’évolution était favorable avec remontée de l’acuité visuelle à 6/10. L’étiologie principale des hémorragies rétro-hyaloïdiennes est rarement une hyperpression céphalique veineuse. Cependant, il faut toujours penser à la rétinopathie de Valsalva lorsque l’interrogatoire révèle la notion d’effort avec blocage thoracique en inspiration.
► Laser-induced reverse transfer has been used to carry out metal depositions. ► A hybrid sol–gel has been applied to the glass substrate prior to LIRT. ► The sol–gel permits the improvement of metal ...adhesion and also plays a protective role.
This article presents a possible use of Laser Induced Reverse Transfer (LIRT) for metal deposition combined with hybrid material prepared using the sol–gel process. The goal was to obtain two dimensional metal gratings with inorganic–organic hybrid material protection on low cost glass substrates. The hybrid material using the sol–gel material is employed here to give better adhesion of metal deposited by LIRT on glass substrates, and also to possibly cover the metal structure. The hybrid material was an organically modified silicate glass based on methacryloxypropyltri-methoxysilane (MATPMS) and zirconium propoxide. The proposed process permits to prototype rapidly small diffractive structure in amplitude mode or to mark two dimensional complicated patterns without complex technologies employing a focalized and computer controlled Nd–YAG laser at 1064nm. The different steps of the technology are also discussed.
A diode-end-pumped, passively Q-switched, Nd:YAG laser with a monolayer graphene as saturable absober simultaneously emitting at 1319 and 1338 nm was demonstrated for the first time. The maximum ...output power, the minimum pulse duration and the highest repetition rate were 586 mW, 317 ns, and 102 kHz, respectively. The corresponding peak power was about 18.1 W.
Resumen Objetivos Valorar en los ojos del cerdo el desplazamiento de las lentes intraoculares subluxadas respecto a la posición inicial tras la realización de una capsulotomía láser Nd: YAG. Métodos ...Se utilizaron 15 ojos de cerdo a los que les realizamos una cirugía extracapsular de cristalino transparente. Tras la introducción de una lente intraocular (LIO) dentro del saco capsular se provocó una diálisis zonular hasta objetivar un desplazamiento de la LIO de un valor mínimo de 4 mm. Efectuamos una capsulotomía láser Nd: YAG en forma de cruz en los 3,5 mm centrales del eje óptico a elevadas energías. Se midió el desplazamiento final de la LIO con la ayuda de una regla milimetrada. Resultados En ninguno de los ojos estudiados se objetivó un desplazamiento significativo en relación a la situación inicial. Conclusiones La capsulotomía láser Nd: YAG en LIOs subluxadas se presenta para ojos estáticos como una maniobra segura a corto plazo.
Abstract Objectives To evaluate the movement from their initial set position of subluxated intraocular lenses (IOL) in pig eyes following Nd: YAG laser capsulotomy. Methods An extracapsular surgical ...intervention of the transparent crystalline lens was performed on 15 pig eyes. After the introduction of an intraocular lens into the capsular sac, a zonular dialysis was carried out to observe the shift of the IOL. We carried out a high intensity Nd: YAG laser capsulotomy in a 3.5 mm cross shape in the central optical axis and then measured the final displacement of the IOL using a millimetre ruler. Results We did not observe a significant shift of the lens in any of the eyes studied. Conclusions Nd: YAG laser capsulotomy is a safe short-term operation for static and subluxated intraocular lenses.
Abstract Root canal irrigants are used to minimize the negative effects of smear layer on endodontic sealer retention. The aim of this study was to evaluate the efficacy of agitation of 17% ...ethylenediaminetetraacetic acid (EDTA) with ultrasonic, 1064-nm Nd:YAG and 980-nm diode laser on the retention of an epoxy-based sealer to the root canal walls. Forty single-rooted bovine teeth were instrumented with ProTaper rotary system and divided into four groups according to the final irrigation protocol (n = 10): (1) 17% EDTA (control); (2) 17% EDTA with 50-s ultrasonic agitation; (3) 17% EDTA with 50-s diode laser (2-W) agitation; and (4) 17% EDTA with 50-s Nd:YAG (1.5-W) laser agitation. After endodontic filling with gutta-percha F5 master cone and Sealer 26, the roots were sectioned at the cervical, middle, and apical root thirds to obtain 1.5-mm slices. Push-out tests were performed using a universal testing machine at a 1 mm/min crosshead speed. Data were analyzed using two-way ANOVA and Tukey's tests (α=0.05). Apical root thirds had significant higher retention values than cervical and middle thirds (p < 0.05). EDTA with 1064-nm Nd:YAG or 980-nm diode laser presented the highest retention values and was significantly different from EDTA with ultrasonic agitation and EDTA only (p < 0.05). Adhesive failures were predominant to EDTA only group. Mixed failures were predominant to all agitation groups. 1064-nm Nd:YAG and 980-nm diode laser EDTA agitation enhanced the retention of the epoxy-based sealer to the root canal walls compared with that due to EDTA only or EDTA with ultrasonic agitation.
Resumo Irrigantes para canais radiculares são usados para minimizar os efeitos negativos da camada de smear na retenção do cimento obturador. O objetivo deste estudo foi avaliar a eficácia da agitação do ácido etilenodiaminotetracético a 17% (EDTA) com ultrassom, Nd:YAG 1064-nm e laser diodo 980-nm na retenção de um cimento obturador à base de resina epóxica nas paredes do canal radicular. Quarenta dentes bovinos unirradiculares foram instrumentados com o sistema rotatório ProTaper e divididos em quatro grupos de acordo com o protocolo de irrigação final (n = 10): (1) EDTA 17% (controle); (2) EDTA 17% com agitação ultrassônica por 50-s; (3) EDTA 17% com agitação com laser diodo (2-W) por 50-s; e (4) EDTA 17% com agitação com laser Nd:YAG (1,5-W) por 50-s. Após obturação endodôntica com cone principal F5 e cimento Sealer 26, as raízes foram seccionadas nos terços radiculares cervical, médio e apical para obtenção de slices de 1,5-mm. Testes de push-out foram realizados utilizando uma máquina universal de ensaios com velocidade de carga de 1 mm/min. Os dados foram analisados utilizando os testes two-way ANOVA e Tukey's (α=0,05). Os terços radiculares apicais tiveram força de adesão significantemente maior que os terços cervical e médio (p<0,05). EDTA com Nd:YAG 1064-nm ou laser diodo 980-nm apresentaram os maiores valores de força de adesão e foram significantemente diferentes do EDTA com agitação ultrassônica e EDTA apenas (p < 0,05). Falhas adesivas foram predominantes apenas no grupo EDTA. Falhas mistas foram predominantes em todos os grupos de agitação. A agitação do EDTA com Nd:YAG 1064-nm e laser diodo 980-nm aumentou a força de adesão do cimento à base de resina epóxica às paredes do canal radicular comparado com a obtida com EDTA apenas ou EDTA com agitação ultrassônica.
The case concerns a 20 year-old woman with a sudden visual loss in her left eye. In the fundus examination, a focal pre-retinal haemorrhage was observed in the superior temporal vascular branch with ...accompanying vitreous haemorrhage. There was a favorable spontaneous outcome. Eighteen months later, she presented with a new visual loss in the same eye, showing a sub-hyaloid pre-macular haemorrhage that was satisfactorily drained by hyaloidotomy using a Nd-YAG laser. The patient had also presented with an upper digestive tract haemorrhage and menorrhagia. A haemostasis study was performed that showed a coagulation factor VII deficiency. This is a very uncommon disorder that has not been previously described in association with the appearance of pre-retinal haemorrhages.
Mujer de 20 años de edad con disminución brusca de visión en el ojo izquierdo. En la exploración de fondo de ojo, se observó una hemorragia prerretiniana focal en la arcada temporal superior con hemovítreo acompañante. La evolución espontánea fue favorable. A los 18 meses presentó una nueva pérdida visual en ese ojo, objetivándose una hemorragia premacular subhialoidea que fue drenada satisfactoriamente mediante una hialoidotomía con láser Nd-YAG. La paciente había presentado además, una hemorragia digestiva alta y menorragia. Se le realizó un estudio de la hemostasia que demostró un déficit del factor VII de la coagulación. Se trata de un trastorno muy infrecuente que, con anterioridad, no se había descrito en asociación a la aparición de hemorragias prerretinianas.
Purpose: The purpose of this study was to evaluate the effects of the application of antioxidant on the shear bond strengths (SBS) of orthodontic brackets bonded to human enamel after extra-coronal ...bleaching with hydrogen peroxide (HP). Materials and methods: Fifty freshly extracted premolars were randomly divided into three groups. One group (Group 1) was bleached with 40% HP (n=20), another group (Group 2) was bleached with 40% HP and activated with an Nd: YAG laser (n=20), and a control group (Group 3) received no treatment (n=10). After the bleaching procedure, Groups 1 and 2 were further divided into two subgroups (Group 1a, Group 1b, Group 2a, and Group 2b). Specimens in Groups 1a and 2a (n=10) received no antioxidant application. A 10% sodium ascorbate solution was applied to specimens in Groups 1b and 2b (n=10). The brackets were then bonded with light-cure adhesive paste to the enamel surfaces of all experimental groups. Specimens were subjected to SBS tests for debonding. Results: The SBS of brackets bonded in Groups 1 and 2 were significantly lower than those of brackets bonded to the control group (p<0.001); however, no statistically significant differences in SBS were noted in Groups 1 and 2 (p>0.001). The antioxidant-treated SBS of brackets in Groups 1b and 2b were significantly higher than those of Groups 1a and 2a (p<0.001). Conclusions: The application of 40% HP had a negative effect on the bond strength. The use of antioxidant for 15 min resulted in the reversal of failed bond strength.
O uso do laser neodymium-yttrium-aluminium-garnet (Nd-YAG) como instrumento auxiliar para o rejuvenescimento propiciou um refinamento da técnica tradicional. Tal procedimento mostra resultados ...satisfatórios com relação ao aprimoramento técnico e à recuperação pós-operatória. OBJETIVO: Evidenciar as alterações histológicas e morfométricas encontradas na pálpebra de humanos após aplicação do laser Nd-YAG e comparar com a pele normal. MATERIAL E MÉTODO: Nove pacientes do sexo feminino foram submetidas à aplicação do laser Nd-YAG em região palpebral direita. A pálpebra esquerda correspondeu à área controle, livre de qualquer tipo de procedimento. Foram realizadas várias aplicações do laser Nd-YAG, sendo que, no último dia, foi realizada biópsia palpebral bilateralmente. Os critérios morfométricos avaliados foram: medida da espessura da epiderme, da área subepidérmica livre de lesão, da zona de degeneração do colágeno e da espessura total da derme. RESULTADOS: Nas áreas submetidas à aplicação do laser Nd-YAG, a espessura média da epiderme foi de 33,53 micrômetros (µm) e a da pele normal foi de 29,61µm (p = 0,1099). A média da medida da área subepidérmica livre de lesão, no lado direito, foi de 40,93µm, e de 36,27µm (p = 0,1373) no esquerdo. A espessura da região de degeneração do colágeno na pálpebra que recebeu tratamento com laser teve média de 293,54µm, enquanto que na pálpebra normal ela foi de 292,22µm (p = 0,4835). No lado onde se aplicou o laser Nd-YAG, a espessura total da derme teve uma média de 681,48µm e, no lado livre de procedimento, 664,14µm (p = 0,3492). DISCUSSÃO E CONCLUSÕES: Apesar da diferença clínica observada após tratamento de lesões de envelhecimento em pálpebra de humanos com o uso do laser Nd-YAG, nota-se que não houve diferença histológica ou morfométrica após tal procedimento.The use of laser Neodymium-Yttrium-Aluminium-Garnet (Nd-YAG) as an auxiliary tool on rejuvenation provided a refining of the traditional technique. This laser procedure show satisfactory results with technical improvement and postoperatory recovery. OBJECTIVES: The aim of this study is to show the histological and morphometrical changes found in human eyelid tissue after the use of laser Nd-YAG and its comparision to the normal structure. MATERIAL AND METHODS: Nine female patients underwent laser Nd-YAG application on their right eyelid. The left eyelid was taken by control-tissue, free of any kind of procedure. It was made many applications of the laser and on the last day, it was made a bilateral biopsy. The morphometrical criteria appraised were: epidermal denseness measure, subepidermal area free of injury, colagen degeneration and total dermal density. RESULTS: In those areas whose underwent laser the epidermal measure was of 33,53 micrometers (µm) and on the normal tissue, was of 29.61µm (p = 0.1099). The subepidermal measure was, on average, of 40.93µm on right side and of 36.27µm on left side (p = 0.1373). The colagen degeneration measure on the right side was of 293.54µm and on the left side was of 292.22µm (p = 0.4835). On the procedure site, the total dermal measure was of 681,48µm and on the free site, it was of 664.14µm (p = 0.3492). DISCUSSION AND CONCLUSIONS: Despite the clinical changes observed after laser Nd-YAG therapy, there were neither histological nor morphometrical significative changes.
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