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1.
J Clin Med ; 12(14)2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37510871

RESUMEN

BACKGROUND: Corneal refractive surgery induces high-order aberrations, specifically spherical aberration (SA). These aberrations can have implications when patients later develop cataracts and require the implantation of multifocal intraocular lenses (MIOLs). MIOLs with asymmetric designs pose challenges in predicting outcomes, particularly in these cases. The aim of this study was to evaluate how different values of SA, resulting from various types of refractive surgeries, affect the optical performance of the FEMTIS Comfort intraocular lens. METHODS: The through-focus modulation transfer function (TF-MTF) curve and high-contrast images of tumbling E were used as parameters to assess the optical performance of the MIOL. These parameters were measured using an adaptive optics visual simulator. RESULTS: Increasingly negative values of SA make the MIOL more bifocal, moderating its extended-depth-of-focus characteristic. Conversely, higher positive SA values cause the TF-MTF curve to shift towards positive vergences, leading to worsened distance vision in the +1.00 to +2.00 D range, but improved vision in the +0.50 D to +1.00 D range. CONCLUSIONS: Assessing SA in patients prior to implanting MIOLs with asymmetric designs is necessary for predicting outcomes and making informed decisions based on the visual requirements of patients.

2.
J Clin Med ; 12(14)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37510792

RESUMEN

Evaluating chromatic aberration for a multifocal intraocular lens (MIOL) in vitro is essential for studying its performance because it helps determine the most appropriate lens for each patient, enhancing surgical outcomes. While refractive MIOLs with angular power variation have shown positive clinical outcomes, studies of these MIOLs on optical benches primarily employed monochromatic green light, neglecting the impact of longitudinal chromatic aberration (LCA) on MIOL performance. To address this gap, we evaluated the through-focus modulation transfer function (TF-MTF) and the point spread function (PSF) of two refractive segmented extended depth of focus intraocular lenses (IOLs) (Femtis Comfort and Precizon Presbyopic), comparing the results with those obtained with two widely known diffractive multifocal intraocular lenses (AcrySof IQ ReSTOR and FineVision Pod F). Measurements of the TF-MTF were conducted using both monochromatic and polychromatic light in a customized optical bench. The refractive designs exhibited distinct haloes in the PSFs. When comparing the refractive and diffractive designs, opposite signs of LCA were observed at near foci. These findings emphasize the influence of the optical design of IOLs on their performance under polychromatic light, providing valuable information for vision care professionals when selecting the most suitable lens for each patient.

3.
J Clin Med ; 11(6)2022 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-35329805

RESUMEN

This study aimed to evaluate in vitro performance refractive segmented EDOF intraocular lenses under polychromatic light using an optical bench that complies with the ISO 11979-2 Norm. The through focus modulation transfer function (TF-MTF) of the Femtis Comfort LS-313 MF15 (Oculentis GmbH, Berlin, Germany) IOL was evaluated for IOLs with three different base powers. The effect of the asymmetry of the segmented designs was evaluated with 3 different wavelengths and with polychromatic light at a 3.0 mm and 5.0 mm pupil diameter. It was demonstrated that the TF-MTF curves exhibit a bifocal profile that, in practice, results in an EDOF design. As a consequence of the LCA, the TF-MTF values in white light were lower than in monochromatic light. Images of the USAF test chart were obtained to confirm the prediction of the TF-MTFs. We found that Femtis Comfort is a bifocal low-addition IOL and this fact can result in an EDOF effect which was obtained previously in clinical trials. Moreover, we showed that the base power influences the IOL optical quality, which results as more effective for high powers (hyperopic eyes) than for low powers (myopic eyes). The LCA of the segmented refractive design was very low and presumably not clinically relevant.

4.
Cir Esp ; 88(4): 222-7, 2010 Oct.
Artículo en Español | MEDLINE | ID: mdl-20667526

RESUMEN

Natural orifice transluminal endoscopic surgery (NOTES), involves a group of new endoscopic approaches to the abdominal cavity, with potential advantages over conventional laparoscopic surgery. It is based on the possibility of performing intra-peritoneal surgical techniques through natural orifices by entering the peritoneal cavity through natural orifices perforating the organ that allows direct access to that cavity (stomach, vagina, rectum, bladder). The possibility of using this same route to access the retroperitoneum and mediastinum has subsequently been postulated. Comments are made on how the technique has been developed, as well as how it has been applied in our country, attempting to give a general view on the risks and benefits of NOTES and the basic requirements to be able to start in this new surgery.


Asunto(s)
Cirugía Endoscópica por Orificios Naturales/historia , Historia del Siglo XXI , Humanos , Cirugía Endoscópica por Orificios Naturales/métodos , Factores de Riesgo , España
5.
Cir. Esp. (Ed. impr.) ; 88(4): 222-227, oct. 2010. ilus, tab
Artículo en Español | IBECS (España) | ID: ibc-135864

RESUMEN

La cirugía endoscópica transluminal a través de orificios naturales (NOTES, del inglés Natural Orifice Translumenal Endoscopic Surgery), engloba un conjunto de nuevas vías de abordaje endoscópico de la cavidad abdominal, con ventajas potenciales sobre la cirugía laparoscópica convencional. Se fundamenta en la posibilidad de realizar técnicas quirúrgicas intraperitoneales mediante la entrada en la cavidad peritoneal a través de los orificios naturales perforando el órgano que permite la entrada directa a dicha cavidad (estómago, vagina, recto, vejiga). Posteriormente se ha postulado la posibilidad de este mismo acceso para acceder al retroperitoneo y al mediastino. A continuación se comenta como se ha desarrollado la técnica y cómo ha sido la aplicación en nuestro país, intentado dar una visión general sobre los riesgos y beneficios de la NOTES y las necesidades básicas para poder iniciarse en esta nueva cirugía (AU)


Natural orifice transluminal endoscopic surgery (NOTES), involves a group of new endoscopic approaches to the abdominal cavity, with potential advantages over conventional laparoscopic surgery. It is based on the possibility of performing intra-peritoneal surgical techniques through natural orifices by entering the peritoneal cavity through natural orifices perforating the organ that allows direct access to that cavity (stomach, vagina, rectum, bladder). The possibility of using this same route to access the retroperitoneum and mediastinum has subsequently been postulated. Comments are made on how the technique has been developed, as well as how it has been applied in our country, attempting to give a general view on the risks and benefits of NOTES and the basic requirements to be able to start in this new surgery (AU)


Asunto(s)
Humanos , Historia del Siglo XXI , Cirugía Endoscópica por Orificios Naturales/historia , Cirugía Endoscópica por Orificios Naturales/métodos , Factores de Riesgo , España
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