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1.
Vestn Oftalmol ; 138(3): 73-81, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-35801884

RESUMEN

PURPOSE: To analyze visual functions in moderate and high myopic patients with retinal detachment that developed after implantation of a trifocal intraocular lens (IOL). MATERIAL AND METHODS: The study analyzed the functional outcomes achieved in 3 patients (4 eyes) with retinal detachment developed after implantation of AcrySof IQ PanOptix («Alcon¼, USA) and AT LISA tri 839 MP («Carl Zeiss Meditec¼, Germany) during the follow-up period of 24 months. Patient examination included measurements of visual acuity at far (4 and 5 m), near (40 cm) and intermediate distances (60 cm, 80 cm), spatial contrast sensitivity, spherical equivalent of refraction, and a survey of patients for subjective satisfaction of the obtained vision. RESULTS: In four eyes of three patients with moderate and high myopia, rhegmatogenous retinal detachment was diagnosed during the follow-up period at 4 to 12 months after phacoemulsification of cataract with trifocal IOL implantation. The best visual indicators were found in patient N. as a result of surgical treatment of bilateral rhegmatogenous retinal detachment due to high myopia: visual acuity (VA) at far distance was 1.0 for each eye (with 100 points on the VF-14 questionnaire). In patients P. and M., after the development of unilateral rhegmatogenous retinal detachment, complete retinal reattachment was achieved after surgery with VA at far distance 0.55 (OS) in patient P. and 0.4 (OD) in patient M. (95 and 86 points on VF-14, respectively). CONCLUSION: Good visual functions were achieved in three patients with trifocal IOL after surgical treatment of the rhegmatogenous retinal detachment that developed due to myopia. The implanted trifocal IOL did not affect the effectiveness of vitrectomy. After the treatment patients retained the ability to see at different distances.


Asunto(s)
Lentes Intraoculares , Miopía , Facoemulsificación , Desprendimiento de Retina , Humanos , Implantación de Lentes Intraoculares/efectos adversos , Miopía/complicaciones , Miopía/diagnóstico , Miopía/cirugía , Satisfacción del Paciente , Facoemulsificación/efectos adversos , Diseño de Prótesis , Refracción Ocular , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/etiología , Desprendimiento de Retina/cirugía
2.
Vestn Oftalmol ; 138(1): 58-63, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-35234422

RESUMEN

Oculocutaneous albinism is a group of autosomal recessive disorders that directly affect the hypopigmentation of the skin, hair, and eyes. According to the World Health Organization, albinism occurs in 1 out of 20 000 people in Europe and North America. Congenital changes in the organ of vision in albinism lead to a significant decrease in the visual functions of patients, worsening their quality of life. PURPOSE: To study the results of surgical treatment with implantation of an artificial iris as a diaphragm element in patients with albinism. MATERIAL AND METHODS: This article was based on the examination and treatment of 2 patients suffering from oculocutaneous albinism, which is characterized by hypopigmentation of the iris and retinal pigment epithelium of the retina, foveolar hypoplasia, low visual acuity, nystagmus, strabismus and excruciating photophobia. The patients were implanted an artificial iris in both eyes with fixation in the capsular bag in the first patient, and in the ciliary sulcus in the second. RESULTS: In both patients, complaints of photophobia and optical phenomena have ceased. Visual acuity increased to 0.2 and remained without regression throughout the entire period of observation. Intraocular pressure and hydrodynamic parameters also remained stable throughout the observation period. The artificial irises were observed by ultrabiomicroscopy to remain in a stable position both when it was implanted in the capsule bag, and when it was seamlessly fixed in the ciliary sulcus. CONCLUSION: The surgical interventions relieved patients from glare, at the same time improving visual acuity without correction, as well as achieving a pronounced cosmetic effect and visual rehabilitation. Artificial irises have proven to be a safe and effective way to treat patients with oculocutaneous albinism.


Asunto(s)
Albinismo Oculocutáneo , Calidad de Vida , Albinismo Oculocutáneo/complicaciones , Albinismo Oculocutáneo/diagnóstico , Albinismo Oculocutáneo/cirugía , Fóvea Central , Humanos , Iris/cirugía , Trastornos de la Visión
3.
Vestn Oftalmol ; 138(1): 64-70, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-35234423

RESUMEN

Posterior chamber phakic intraocular lens (PIOL) implantation is a widely accepted and performed refractive surgery for correction of moderate and high myopia used when corneal laser ablation procedures are not suitable. This paper analyzes literature data to reveal the advantages and limitations of the technology.


Asunto(s)
Lentes Intraoculares , Miopía , Lentes Intraoculares Fáquicas , Errores de Refracción , Humanos , Implantación de Lentes Intraoculares/efectos adversos , Implantación de Lentes Intraoculares/métodos , Miopía/diagnóstico , Miopía/cirugía , Lentes Intraoculares Fáquicas/efectos adversos , Refracción Ocular
4.
Vestn Oftalmol ; 136(1): 80-89, 2020.
Artículo en Ruso | MEDLINE | ID: mdl-32241973

RESUMEN

PURPOSE: To compare visual outcomes after implantation of two models of diffractive trifocal IOLs using various vision assessment systems. MATERIAL AND METHODS: The study included 25 patients (25 eyes) who were implanted with AcrySof IQ PanOptix (TFN) and 25 patients (25 eyes) implanted with AT LISA tri 839 MP (TRI). Postoperative examination at 1 year included assessment of monocular visual acuity for far, intermediate and near distance using decimal scale, as well as LogMAR and an interactive computer program (ICP). Contrast sensitivity was assessed with the Optec 6500 device. A questionnaire was used to evaluate subjective quality of vision and the intensity of optical phenomena. RESULTS: Uncorrected visual acuity (UCVA) at distance, intermediate and near was better in the TFN group in comparison with the TRI group as measured with decimal scale, ICP and LogMAR. Under photopic and mesopic conditions with and without glare, at all spatial frequencies the contrast sensitivity function (CSF) was higher after implantation of TFN in comparison with TRI. The average VF-14 score was 97.2 after implantation of TFN and 96.7 after implantation of TRI. The amount of patients who required spectacle correction after the surgery was 5.5% less in the TFN group compared to the TRI group. CONCLUSION: High visual outcomes at all distances were observed in patients after implantation of both trifocal IOLs with TFN showing a slight advantage. Evaluation of the visual outcomes using various systems showed the benefits of the ICP assessment. The CSF had typical configuration with maximum value in the mid-range region and a decrease in the high-frequency range after implantation of both IOLs, however the indicators were better in the TFN group. The postoperative period was characterized by high levels of patient satisfaction and spectacle independence in both groups.


Asunto(s)
Lentes Intraoculares , Sensibilidad de Contraste , Humanos , Implantación de Lentes Intraoculares , Satisfacción del Paciente , Facoemulsificación , Estudios Prospectivos , Diseño de Prótesis , Refracción Ocular
5.
Vestn Oftalmol ; 135(6): 60-66, 2019.
Artículo en Ruso | MEDLINE | ID: mdl-32015309

RESUMEN

Presence of an extensive iris defect requires implantation of artificial iris (AI) to close it. With biometric parameters of the AI being as close to an intact eye as possible, it becomes viable to achieve good clinical and functional results with the surgery. PURPOSE: To validate the optimal biometric parameters of the pupil of artificial iris using methods of clinical and theoretical analysis. MATERIAL AND METHODS: Mathematical modeling was used to determine the main criteria characterizing natural aperture diaphragm of the eye (pupil) which were considered in the theoretical substantiation of optimal biometric parameters of the AI's pupil. Parameters determined during the theoretical stage of the study were used in the development of iris-lens diaphragm (ILD) for clinical application. The study included 6 patients (6 eyes) with post-traumatic aniridia and cataract requiring reconstructive surgery. In the course of the surgery, intraocular lens and ILD were sequentially implanted into the capsular bag using injector system. The patients underwent standard and special ophthalmic examination including optical coherence tomography (OCT) of the central retina before the surgery and after 3 months. RESULTS: According to mathematical modeling, optimal shape of the ILD pupil was determined to be a circle. The suggested diameter for the ILD pupil is 3.2 mm. The pupil must be located on the optical axis of the eye. Distortions of the retinal image become minimal with pupil's edge thickness of 0.2 mm and cone-shaped profile. After Implantation of the developed ILD with pupil parameters determined during the theoretical substantiation, patients of the study exhibited increased visual acuity and satisfaction with results of the surgery. CONCLUSION: The biometric parameters of the ILD pupil determined during the clinical-theoretical study can be used in modern ILD models.


Asunto(s)
Aniridia , Lentes Intraoculares , Humanos , Iris , Pupila , Agudeza Visual
6.
Vestn Oftalmol ; 133(6): 23-29, 2017.
Artículo en Ruso | MEDLINE | ID: mdl-29319666

RESUMEN

The diversity of methodological approaches and lack of pathogenetically reasonable tactics for patients with combined ocular injuries became the basis for the development and systematization of surgical rehabilitation stages of patients, in whom post-traumatic cataract is combined with post-traumatic aniridia and corneal scarring. AIM: to construct a visual rehabilitation approach to patients with post-traumatic defects of the anterior eye segment following optical-reconstructive surgery that involved implantation of an iris-lens diaphragm (ILD). MATERIAL AND METHODS: We have analyzed 80 reconstructive cases with ILD implantation in patients with post-traumatic aniridia and corneal damage. These patients constituted the first study group (Group 1). We have also investigated 58 eyes with residual ametropy and stable visual function 1 year after ILD implantation before and after conducting a laser keratorefractive surgery. These patients were assigned to the second study group (Group 2). RESULTS: Rehabilitation approach to patients after anterior segment injuries that has been proposed allows to achieve high clinical and functional results and reduce the risk of intra- and postoperative complications. CONCLUSION: The proposed approach to patients after optical-reconstructive surgery with iris-lens diaphragm implantation followed by keratorefractive surgery is an effective method of visual rehabilitation of anterior eye segment post-traumatic defects.


Asunto(s)
Aniridia , Lesiones Oculares Penetrantes , Implantación de Lentes Intraoculares , Procedimientos Quirúrgicos Refractivos , Adulto , Aniridia/diagnóstico , Aniridia/etiología , Aniridia/cirugía , Segmento Anterior del Ojo/diagnóstico por imagen , Segmento Anterior del Ojo/lesiones , Segmento Anterior del Ojo/cirugía , Lesiones Oculares Penetrantes/complicaciones , Lesiones Oculares Penetrantes/diagnóstico , Lesiones Oculares Penetrantes/rehabilitación , Femenino , Humanos , Iris/diagnóstico por imagen , Iris/cirugía , Implantación de Lentes Intraoculares/instrumentación , Implantación de Lentes Intraoculares/métodos , Implantación de Lentes Intraoculares/rehabilitación , Lentes Intraoculares , Masculino , Procedimientos Quirúrgicos Refractivos/métodos , Procedimientos Quirúrgicos Refractivos/rehabilitación , Federación de Rusia , Resultado del Tratamiento , Agudeza Visual
7.
Sci Rep ; 5: 18480, 2015 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-26690826

RESUMEN

The spin wave dynamics in patterned magnetic nanostructures is under intensive study during the last two decades. On the one hand, this interest is generated by new physics that can be explored in such structures. On the other hand, with the development of nanolithography, patterned nanoelements and their arrays can be used in many practical applications (magnetic recording systems both as media and read-write heads, magnetic random access memory, and spin-torque oscillators just to name a few). In the present work the evolution of spin wave spectra of an array of non-interacting Permalloy submicron circular dots for the case of magnetic field deviation from the normal to the array plane have been studied by ferromagnetic resonance technique. It is shown that such symmetry violation leads to a splitting of spin-wave modes, and that the number of the split peaks depends on the mode number. A quantitative description of the observed spectra is given using a perturbation theory for small angles of field inclination from the symmetry direction. The obtained results give possibility to predict transformation of spin wave spectra depending on direction of the external magnetic field that can be important for spintronic and nanomagnetic applications.

8.
J Clin Pathol ; 68(5): 351-5, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25661796

RESUMEN

AIMS: To investigate the potential prognostic impact of the lymphocyte-monocyte ratio (LMR) in a large European cohort of patients with localised upper urinary tract urothelial carcinoma (UTUC). The LMR as an indicator of systemic inflammatory response has been shown to represent a potential prognostic factor in various types of human cancers. Up to date, the prognostic significance of the LMR in UTUC has not been evaluated. METHODS: Clinico-pathological data from 182 non-metastatic patients with UTUC, operated between 1990 and 2012 at a single tertiary academic centre, were evaluated retrospectively. Pretreatment LMR was assessed 1 day before surgery. Patients were categorised using an LMR cut-off value of 2.0 according to a calculation by receiver-operating curve analysis. Patients' overall survival (OS) was assessed using the Kaplan-Meier method. To evaluate the independent prognostic significance of the LMR, a multivariate proportional Cox regression model was applied for OS. RESULTS: In multivariate analyses, age on the date of surgery (<65 vs ≥65 years, HR=2.10, 95% CI 1.22 to 3.64), pathological T-stage (pT1 vs pT2-4, HR=2.15, 95% CI 1.26 to 3.67), as well as the LMR (<2 vs ≥2, HR=0.56, 95% CI 0.35 to 0.92) were independent predictors of OS of patients with UTUC. CONCLUSIONS: In the cohort studied, patients with an elevated (≥2) preoperative LMR had a subsequently longer OS after radical surgery for UTUC, compared with those with a low (<2) preoperative LMR. Thus, we believe this parameter might be considered an additional prognostic factor in UTUC in the future.


Asunto(s)
Carcinoma/sangre , Recuento de Linfocitos , Linfocitos , Monocitos , Neoplasias Urológicas/sangre , Urotelio/patología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Austria , Carcinoma/patología , Carcinoma/terapia , Distribución de Chi-Cuadrado , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Neoplasias Urológicas/mortalidad , Neoplasias Urológicas/patología , Neoplasias Urológicas/terapia
9.
J Nanosci Nanotechnol ; 12(9): 7486-90, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23035501

RESUMEN

Pulsed electrodeposition prepared porous alumina templates with Ni nanowires pore filling ranged from 1 to 100%, depending on the alumina barrier-layer thickness, were probed by continuous wave ferromagnetic resonance at room temperature. For completely filled samples, a single resonance peak was observed in the whole range of angles between the applied magnetic field and normal to the sample plane. Its position was described by Kittel formula that takes into account shape anisotropy of individual Ni wires and dipolar interactions between them. For the samples with lower pore filling the effective anisotropy field decreased and the resonance linewidth in the perpendicular configuration increased. Also a quite intense second peak was observed at lower fields for these samples. These changes are associated with reduction of pore filling percentage that can lead to decrease of dipolar interactions between nanowires and to appearance of magnetic inhomogeneities inside wires.

10.
J Nanosci Nanotechnol ; 11(10): 8907-11, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22400279

RESUMEN

Nanostructured Pd-Fe thin films with varied Fe content were prepared by electrodeposition technique from organic electrolytes on Cu and brass substrates. The structure and the magnetic properties of the films were investigated prior to post-deposition annealing. The structure of the Pd1-xFe(x) thin film with x = 0.14, 0.24, and 0.52 was determined by X-ray diffraction (XRD) and transmission electron microscopy (TEM) as a solid solution of iron in palladium face-centered cubic lattice with the (111) orientation of nanograins relatively to the substrate surface. The films with higher iron concentration, x = 0.74, 0.91, have structure of a solid solution based on the body-centered cubic lattice. The average grain size determined by the scanning electron microscopy (SEM) for the first two alloys is 7-10 nm, and for the latter ones it is about 120 nm. The saturation magnetization of the films has linear dependence on the iron content, but coercivity has non-monotonic dependence on x, i.e., the films with x = 0.68 show highest coercivity. The magnetic anisotropy of the samples is studied by ferromagnetic resonance (FMR) spectroscopy.

11.
J Phys Condens Matter ; 22(35): 355306, 2010 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-21403285

RESUMEN

Mechanisms of non-radiative recombination of electron-hole complexes in Cd(Mn)Se/Zn(Mn)Se quantum dots accompanied by interconfigurational excitations of Mn(2+) ions are analyzed within the framework of the single-electron model of deep 3d levels in semiconductors. In addition to the mechanisms caused by Coulomb and exchange interactions, which are related because of the Pauli principle, another mechanism due to sp-d mixing is considered. It is shown that the Coulomb mechanism reduces to long-range dipole-dipole energy transfer from photoexcited quantum dots to Mn(2+) ions. The recombination due to the Coulomb mechanism is allowed for any states of Mn(2+) ions and e-h complexes. In contrast, short-range exchange and sp-d recombinations are subject to spin selection rules, which are the result of strong lh-hh splitting of hole states in quantum dots. Estimates show that efficiency of the sp-d mechanism can considerably exceed that of the Coulomb mechanism. The phonon-assisted recombination and processes involving the upper excited states of Mn(2+) ions are studied. The increase in PL intensity of an ensemble of quantum dots in a magnetic field perpendicular to the sample growth plane observed earlier is analyzed as a possible manifestation of the spin-dependent recombination.

12.
Vestn Oftalmol ; 123(4): 3-6, 2007.
Artículo en Ruso | MEDLINE | ID: mdl-17802751

RESUMEN

The authors analyzed the results of binocular refractive lens exchange with a pseudoaccomodative AcrySof ReSTOR multifocal diffractive intraocular lens (IOL) in 24 patients (48 eyes) aged 40 to 61 years. Preoperative hyperopic refraction ranged from 1.0 to 6.0 diopters. One week postoperatively, a high percentage of the operated eyes had fine results of uncorrected distance and near visual acuity; the mean contrast sensitivity was found to be slightly reduced at high frequencies. 87.5% of the patients were completely satisfied with the results of binocular AcrySof ReSTOR implantation. Refractive lens exchange with an AcrySof ReSTOR multifocal IOL is a reasonable option for presbyopia in hyperopic patients and provides high functional results. A contrast sensitivity reduction on high frequencies on high frequencies can limit satisfactory results after AcrySof ReSTOR IOL implantation in case of some professions.


Asunto(s)
Implantación de Lentes Intraoculares , Lentes Intraoculares , Facoemulsificación/métodos , Presbiopía/cirugía , Refracción Ocular , Acomodación Ocular/fisiología , Adulto , Sensibilidad de Contraste , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Presbiopía/fisiopatología , Diseño de Prótesis , Resultado del Tratamiento
13.
Vestn Oftalmol ; 120(5): 12-4, 2004.
Artículo en Ruso | MEDLINE | ID: mdl-15529530

RESUMEN

Eighty-four eye were examined in 67 patients after phacoemulsification with intracapsular IOL implantation. The patients were shared, with respect to IOL rigidity, between 2 groups: group 1--rigid PMMA lenses and group 2--soft hydrogel and acryl lenses. The inclination angle was evaluated for different lens types by using an elaborated mathematical formula. The lenses had capsular fixation in all cases. The deviation angle ranged from 0.58 to 1.22 degrees. The difference between the inclination angle and ocular visual axis for rigid and soft lenses was statistically reliable (p < 0.05). The inclination angle of the optic axis in case of soft lenses versus rigid lenses was to a greater extent pronounced after 2 months of observation. However, the conclusion is not final due to continuous fibrosis of the capsular sac, which affects dynamically the IOL positioning. Therefore, similar studies will be made after 12-14 months to enable final conclusions.


Asunto(s)
Implantación de Lentes Intraoculares , Lentes Intraoculares , Facoemulsificación , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Modelos Teóricos , Polimetil Metacrilato , Factores de Tiempo
14.
Proc Natl Acad Sci U S A ; 97(22): 11875-9, 2000 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-11035808

RESUMEN

Mineral inclusions in diamonds provide an important source of information about the composition of the continental lithosphere at depths exceeding 120-150 km, i.e., within the diamond stability field. Fossilized high pressures in coesite inclusions from a Venezuela diamond have been identified and measured by using laser Raman and synchrotron x-ray microanalytical techniques. Micro-Raman measurements on an intact inclusion of remnant vibrational band shifts give a high confining pressure of 3.62 (+/-0.18) GPa. Synchrotron single-crystal diffraction measurements of the volume compression are in accord with the Raman results and also revealed direct structural information on the state of the inclusion. In contrast to olivine and garnet inclusions, the thermoelasticity of coesite favors accurate identification of pressure preservation. Owing to the unique combination of physical properties of coesite and diamond, this "coesite-in-diamond" geobarometer is virtually independent of temperature, allowing an estimation of the initial pressure of Venezuela diamond formation of 5.5 (+/-0.5) GPa.

15.
Science ; 269(5225): 822-5, 1995 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-17778742

RESUMEN

An olivine nephelinite from the lower part of a thick alkalic ultrabasic and mafic sequence of volcanic rocks of the northeastern part of the Siberian flood basalt province (SFBP) yielded a (40)Ar/(39)Ar plateau age of 253.3 +/- 2.6 million years, distinctly older than the main tholeiitic pulse of the SFBP at 250.0 million years. Olivine phenocrysts of this rock showed (3)He/(4)He ratios up to 12.7 times the atmospheric ratio; these values suggest a lower mantle plume origin. The neodymium and strontium isotopes, rare earth element concentration patterns, and cerium/lead ratios of the associated rocks were also consistent with their derivation from a near-chondritic, primitive plume. Geochemical data from the 250-million-year-old volcanic rocks higher up in the sequence indicate interaction of this high-(3)He SFBP plume with a suboceanic-type upper mantle beneath Siberia.

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