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1.
Ophthalmologe ; 112(10): 834-9, 2015 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-26040794

RESUMEN

BACKGROUND: In the early postoperative period following uncomplicated cataract surgery, the correlation of corrected distance visual acuity (CDVA) and the increase in corneal thickness and anterior chamber depth (ACD) are investigated. PATIENTS AND METHODS: A total of 54 cataract patients with a mean age of 70 ± 8.4 years were included in this prospective study. Surgery was carried out on one eye of each patient according to the study protocol. Refraction, CDVA and ACD were evaluated 1 day and 1 week postoperatively and compared with the pachymetry results measured with the Pentacam. RESULTS: The mean postoperative CDVA significantly improved from 0.31 ± 0.24 logMAR to 0.18 ± 0.22 logMAR after one day and up to 0.06 ± 0.13 logMAR one week after surgery (p < 0.05). The mean spherical equivalent was - 0.52 ± 0.69 D after one day and - 0.50 ± 0.82 D one week after surgery and showed only minimal differences compared to the mean target refraction of - 0.39 ± 0.70 D. Postoperative corneal thickness showed a significant increase compared to the preoperative results (p < 0.05) on both visits: the mean difference was 33.26 ± 50.20 µm (- 17 to 315 µm) on the first day and 20.22 ± 23.15 µm (- 10 to 99 µm) one week after surgery. Up to 7 days postoperatively the increase in corneal thickness and CDVA showed only moderate or no correlations (r = 0.465 vs. r = 0.072, respectively). Regarding pachymetry and ACD values, no or only low correlations were found. CONCLUSION: The significant increase in corneal thickness on the first and seventh day shows no to moderate correlation to the CDVA. Nevertheless, a good and early rehabilitation of visual acuity following uncomplicated cataract surgery is possible. Intraocular pressure measurement can lead to false high results due to an increase in corneal thickness.


Asunto(s)
Paquimetría Corneal , Lentes Intraoculares , Complicaciones Posoperatorias/etiología , Anciano , Cámara Anterior , Percepción de Distancia , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Estudios Prospectivos , Refracción Ocular , Estadística como Asunto , Agudeza Visual
2.
Klin Monbl Augenheilkd ; 232(7): 867-73, 2015 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-25853945

RESUMEN

PURPOSE: The purpose of this study was to evaluate the functional results and quality of vision after implantation of an aspheric, aberration-neutral, monofocal toric intraocular lens (IOL). PATIENTS AND METHODS: 18 eyes of 13 patients were enrolled in this prospective clinical study. The T-flex aspheric, aberration-free toric IOL (Rayner Intraocular Lenses Limited, U. K.) was implanted after femtosecond or standard phacoemulsification. Follow-up examinations were performed two to four months after surgery; these included subjective refraction, ETDRS uncorrected (UDVA) and corrected distance visual acuity (CDVA), wavefront analysis, measurements of stray light (C-Quant), and a questionnaire. RESULTS: Median UDVA was 0.06 logMAR (range: 0.30 to - 0.18 logMAR) postoperatively. Median CDVA increased from 0.20 logMAR (range: 0.64 to 0.00 logMAR) preoperatively to - 0.07 logMAR (range: 0.16 to - 0.26 logMAR) postoperatively. The median difference between achieved versus intended spherical equivalent was - 0.08 D (range: - 1.25 to + 0.65 D). Median subjective cylinder improved from - 2.00 D (range: - 6.50 to - 0.25 D) preoperatively to - 0.50 D (range: - 1.25 to 0.00 D) postoperatively. The median spherical aberrations (6 mm pupil size) were - 0.38 µm (range: - 0.69 to - 0.10 µm) postoperatively. Measurements of stray light (C-Quant) revealed a median value of 1.28 log(s) (range: 0.92 to 1.61 log[s]). CONCLUSION: The T-flex aspheric toric IOL provided beneficial and predictable functional results after surgery. The implantation of the T-flex is an effective method to correct a large range of corneal astigmatism.


Asunto(s)
Astigmatismo/diagnóstico , Astigmatismo/cirugía , Extracción de Catarata/métodos , Implantación de Lentes Intraoculares/métodos , Lentes Intraoculares , Anciano , Extracción de Catarata/instrumentación , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Resultado del Tratamiento , Agudeza Visual
3.
Klin Monbl Augenheilkd ; 232(2): 181-8, 2015 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-25178043

RESUMEN

PURPOSE: The aim of this study was to perform a clinical evaluation of the functional results and quality of vision after implantation of an aspheric, aberration-neutral, monofocal intraocular lens (IOL). PATIENTS AND METHODS: 47 eyes of 34 patients (median age: 68 years) with cataract were enrolled in this prospective clinical study that had Ethics Committee approval. The C-flex or Superflex aspheric IOL (Rayner, UK) was implanted after phacoemulsification. Follow-up examinations were performed two to four months after surgery including subjective refraction, ETDRS uncorrected (UDVA) and corrected distance visual acuity (CDVA), wavefront analysis, analysis of stray light (C-Quant), contrast sensitivity under different lighting conditions (F. A. C. T.) and a questionnaire. RESULTS: Two to four months after surgery, median UDVA was 0.08 logMAR (range: 0.64 to - 0.18 logMAR, n = 41). Median CDVA increased from 0.30 logMAR (range: 1.00 to - 0.02 logMAR) preoperatively to - 0.08 logMAR (range: 0.16 to - 0.22 logMAR) postoperatively (n = 47). Median difference between achieved vs. intended (Holladay 1-formula) spherical equivalent was + 0.06 D (range: - 1.06 to + 0.87 D). Median total HOA RMS (6 mm pupil size) was 0.66 µm (range: 0.41 to 1.19 µm). The median spherical aberrations were - 0.36 µm (range: - 0.70 to - 0.17 µm). Analysis of stray light (C-Quant) revealed a median value of 1.21 log(s) (range: 0.79 to 1.57 log[s]). CONCLUSION: The C-flex and Superflex aspheric IOLs provide good and predictable functional results. Patients are not negatively influenced by stray light and show slightly negative spherical aberrations.


Asunto(s)
Implantación de Lentes Intraoculares , Lentes Intraoculares , Recuperación de la Función , Errores de Refracción/diagnóstico , Errores de Refracción/terapia , Agudeza Visual , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Resultado del Tratamiento
4.
Klin Monbl Augenheilkd ; 230(8): 786-90, 2013 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-23757172

RESUMEN

Aniridia is defined as missing iris tissue which can be partial, subtotal or total. Characteristic clinical symptoms include photophobia and decreased visual acuity due to an increased light perception. In addition, disturbing cosmetic problems are prevalent. Modern iris reconstruction implants offer visual and cosmetic rehabilitation. Amongst them are aniridia intraocular lenses (IOL), iris segment implants and the "artificial iris". Different overall and pupil diameters are available for total or partial implants. At the same time aphakia or cataract can be treated when using aniridia IOLs. Intra- and extracapsular fixation is possible. The "artificial iris" can be folded and implanted through small incisions. The aesthetic results are improved significantly due to customised colour selection providing increased patient satisfaction postoperatively.


Asunto(s)
Aniridia/complicaciones , Aniridia/terapia , Ojo Artificial , Lentes Intraoculares , Procedimientos de Cirugía Plástica/instrumentación , Trastornos de la Visión/etiología , Trastornos de la Visión/rehabilitación , Humanos , Implantación de Lentes Intraoculares/métodos
5.
Ophthalmologe ; 110(11): 1058-62, 2013 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-23595652

RESUMEN

BACKGROUND: The aim of the study was a clinical evaluation of an intraocular lens (IOL) with a segmental multifocal optic design and near addition of + 3.0 D as part of a CE approval study. PATIENTS AND METHODS: In a multicenter study the LENTIS Mplus LS-312 MF IOL (Oculentis) was implanted in 134 eyes of 79 patients with a mean age of 68 ± 12 years. The multifocality is achieved by implementation of a distance part and a segmented near sector. Three months after surgery, uncorrected and best corrected distance visual acuity (UCDVA and BCDVA, respectively), near visual acuity (UCNVA and BCNVA, respectively), contrast vision and patient satisfaction (questionnaire) were evaluated. RESULTS: The IOLs were implanted uneventfully either unilaterally or bilaterally and 3 months postoperatively (n = 86 eyes) the following mean visual acuities were obtained (logMAR): UCDVA = 0.05, BCDVA = - 0.01, UCNVA = 0.09 and BCNVA = 0.02. Contrast sensitivity (n = 25 eyes) was within normal limits. Of the 66 questioned patients 10.6% spontaneously reported halos and 3% glare. CONCLUSION: This new innovative multifocal IOL concept showed very good functional results as well as high patient satisfaction.


Asunto(s)
Implantación de Lentes Intraoculares/estadística & datos numéricos , Lentes Intraoculares/estadística & datos numéricos , Errores de Refracción/diagnóstico , Errores de Refracción/epidemiología , Trastornos de la Visión/epidemiología , Trastornos de la Visión/cirugía , Adulto , Anciano , Análisis de Falla de Equipo , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente/estadística & datos numéricos , Prevalencia , Diseño de Prótesis , Resultado del Tratamiento , Trastornos de la Visión/diagnóstico , Adulto Joven
6.
Ophthalmologe ; 110(12): 1163-70, 2013 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-23338530

RESUMEN

PURPOSE: The purpose of this study was to evaluate the results of bilateral intrastromal femtosecond laser correction of presbyopia (INTRACOR). METHODS: In a prospective study 17 patients were enrolled who had previously received binocular treatment in a two-step approach. Postoperative (4-8 months) outcomes were compared with a matched control group who had undergone only unilateral surgery of the non-dominant eye (n = 17 patients, 24 months after surgery). RESULTS: The binocular distance corrected near visual acuity (DCNVA) showed the same median but lower scattering of values after bilateral treatment: 0.10 (median in logMAR) (0.30/- 0.10 min/max) (study) versus 0.10 (0.50/- 0.10) (control). In the study group, however, a higher loss of binocular corrected distance visual acuity (CDVA) was found: 23.5 %, 70.6 %, 5.9 % (0, - 1, - 2 lines) (study) versus 35.3 %, 64.7 % and 0 %, respectively (control). CONCLUSIONS: Regarding the reduced CDVA INTRACOR should initially only be performed in the non-dominant eye. In selected cases binocular treatment can improve DCNVA; however, careful risk-benefit assessment and informed consent are necessary.


Asunto(s)
Sustancia Propia/cirugía , Queratomileusis por Láser In Situ/métodos , Presbiopía/diagnóstico , Presbiopía/cirugía , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/cirugía , Agudeza Visual , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Presbiopía/complicaciones , Recuperación de la Función , Resultado del Tratamiento , Trastornos de la Visión/etiología , Adulto Joven
7.
Ophthalmologe ; 108(10): 952-6, 2011 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-21853217

RESUMEN

PURPOSE: Multifocal intraocular lenses (MIOL) are known to induce various photic phenomena depending on the optical principle. The aim of this study was to investigate the correlation between stray light measurements performed with the C-Quant (Oculus, Germany) and the results of a subjective patient questionnaire. PATIENTS AND METHODS: In this study three different MIOLs were compared: AMO ReZoom (refractive design, n=10), AMO ZM900 (diffractive design, n=10) and Oculentis Mplus (near segment design, n=10). Cataract and refractive patients were enrolled in the study. Functional results were evaluated at least 3 months postoperatively followed by stray light measurements and a subjective questionnaire. RESULTS: Surgery was performed for all patients without complications. The three groups were matched for age, IOL power and corrected distance visual acuity (CDVA). Significantly different stray light (median) values log(s) were found (Kruskal-Wallis test, p<0.05): 1.12 log (refractive), 1.13 log (segment) and 1.28 log (diffractive). The subjective questionnaire did not show differences in glare perception but refractive MIOL patients noticed more halos surrounding light sources than the diffractive and segment MIOL patients. CONCLUSIONS: Stray light and subjective photopic phenomena do not show any basic correlation. Measurements in patients with refractive MIOLs showed less stray light than near segment or diffractive MIOLs. However, refractive MIOLs induced more halos compared to the other groups analyzed.


Asunto(s)
Deslumbramiento , Lentes Intraoculares/efectos adversos , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/etiología , Resultado del Tratamiento , Adulto , Anciano , Análisis de Falla de Equipo , Femenino , Humanos , Luz , Masculino , Persona de Mediana Edad , Dispersión de Radiación
8.
Ophthalmologe ; 108(9): 852-8, 2011 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-21720876

RESUMEN

BACKGROUND: The goal of this study was to determine the accuracy of autorefraction measurements in patients after INTRACOR intrastromal femtosecond laser treatment of presbyopia by comparing the agreement between the subjective and objective refraction. PATIENTS AND METHODS: In this study the data of 19 patients with a mean age of 56.5±6.0 years following INTRACOR treatment were analyzed pre-operatively and 12 months postoperatively. Measurements of the subjective refraction and the results of the autorefractor Nidek-660A in miosis were compared. INTRACOR is a refractive intrastromal femtosecond laser treatment to correct presbyopia. During the procedure a series of five concentric rings in the central stroma are cut which cause a change in the curvature of the cornea. RESULTS: The differences in sphere and spherical equivalent between subjective refraction and autorefraction were not significant (t-test p>0.05 and Wilcoxon test p>0.05). Comparing the cylinder of the two measurements a significant difference (t-test p<0.05) was found. Focusing on the difference of the postoperative measurements of the subjective refraction and autorefraction a correlation (within ±0.5 D) of 89% in the sphere, 100% in cylinder and 68% in the spherical equivalent was detected. With one exception the differences in sphere, cylinder and the spherical equivalent were within ±1.25 D. In several patients the performance of the autorefraction with the Nidek-660A was somewhat complicated and the measures had to be repeated frequently. CONCLUSION: The agreement between subjective refraction and objective measurements of the Nidek-660A of patients following INTRACOR-treatment was good. However there was a significant difference in the cylinder values. Therefore thorough comparison of measurements obtained with the autorefractor and the subjective refraction is recommended.


Asunto(s)
Cirugía Laser de Córnea/métodos , Presbiopía/cirugía , Refracción Ocular , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estudios Prospectivos
9.
Ophthalmologe ; 108(1): 52-6, 2011 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-20922529

RESUMEN

BACKGROUND: The aim of this study was to investigate the effect of applanation tonometry on the accuracy of biometric measurements and the reproducibility of keratometric measurements. PATIENTS AND METHODS: In this clinical prospective study a total of 16 patients were enrolled who presented for cataract surgery on 30 eyes. Biometry measurements were made using an IOLMaster optical biometer before and 10 min after standard Goldmann applanation tonometry. Local anesthesia was achieved by administering one drop of fluorescein-stained oxybuprocaine 0.4%. RESULTS: The mean absolute difference of intraocular lens power for emmetropia was 0.31 ± 0.33 D (range -1.56 to +1.12 D) and the mean standard deviation for R1 and R2 (n=28 eyes) was 0.014 ± 0.013 mm before and 0.024 ± 0.021 mm after tonometry. This difference was statistically significant (t-test, p<0.01). Moderate to severe irregular corneal surfaces were noted in some cases after tonometry. CONCLUSIONS: Local anesthesia and applanation tonometry reduced the accuracy of IOL power calculations with differences exceeding ± 1 D and the reliability of consecutive keratometry measurements decreased significantly. Therefore, it is advisable to perform biometry measurements at the very beginning of the preoperative examination.


Asunto(s)
Biometría/métodos , Extracción de Catarata/métodos , Catarata/diagnóstico , Tonometría Ocular/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Klin Monbl Augenheilkd ; 227(8): 624-9, 2010 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-20706970

RESUMEN

Cataract surgery is evolving more and more into a refractive procedure with high expectations in terms of visual rehabilitation. Especially patients presenting after previous Excimer laser corneal surgery are used to being independent from glasses. Unfortunately, some of these patients showed unexpected hyperopic surprises after cataract surgery in the past. The changes of corneal radii and keratometer index as well as the inaccurate prediction of the postoperative intraocular lens (IOL) position using different formulas were determined as error sources which led to a reduced IOL power calculation in dioptres. Several methods have been proposed to solve this problem which can be divided in two groups. On the one hand, there are methods that depend on refraction and biometry values before the initial treatment (e. g., clinical history, Feiz-Mannis, double-K, adjusted effective refractive power [EffRadj]-, cornea bypass/Wake Forest methods as well as correction factors to adjust K-values) and on the other hand procedures that only need current pre-cataract surgery measurements (e. g., contact lens method, corneal topography systems, ray tracing, aphakic refraction technique, correction factors to adjust K-values and new formulas including Haigis-L or BESSt and recently a novel pachymetry method). This review describes these procedures and analyses their strengths and weaknesses. The number of presented methods emphasises already that no perfect solution has been determined so far that would be valid for every patient. Some methods do provide a good predictability; however, individual deviations can occur. In general, it is advisable to inform the patient about the higher risk for an inaccurate IOL power calculation. It can be helpful to compare the results of different methods indicating the importance to provide all required individual data by the refractive surgeon already.


Asunto(s)
Lentes Intraoculares , Refracción Ocular , Procedimientos Quirúrgicos Refractivos , Astigmatismo/etiología , Astigmatismo/prevención & control , Biometría/métodos , Topografía de la Córnea/métodos , Humanos , Satisfacción del Paciente , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Reoperación , Factores de Riesgo
11.
Ophthalmologe ; 105(9): 810-7, 2008 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-18751984

RESUMEN

Modern Ophthalmology is currently experiencing a boom in anterior segment analysis tools that can increasingly gather information with one short measurement. These systems are based e.g. on so-called Scheimpflug (Pentacam, Galilei), slitlamp, and Placido technologies (Orbscan IIz) and other measurement systems. They help in analyzing the cornea in detail, including calculation of corneal wavefront. In addition, morphological and anatomical parameters such as anterior chamber depth, pachymetry, chamber angle, and lens densitometry can be analyzed. That makes these new technologies of interest for refractive surgery as well as for screening procedures such as Glaucoma, Keratoconus and others. This survey focuses on the two models, Oculus Pentacam and B&L Orbscan IIz as representative of all the other systems, as they are the most successful machines in this field.


Asunto(s)
Segmento Anterior del Ojo/anatomía & histología , Córnea/anatomía & histología , Enfermedades de la Córnea/diagnóstico , Topografía de la Córnea/métodos , Técnicas de Diagnóstico Oftalmológico , Fotograbar/métodos , Errores de Refracción/diagnóstico , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Humanos , Queratocono/diagnóstico , Implantación de Lentes Intraoculares , Persona de Mediana Edad , Modelos Estadísticos , Procedimientos Quirúrgicos Refractivos , Programas Informáticos
12.
Ophthalmologe ; 105(6): 522-6, 2008 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-18542968

RESUMEN

Multifocal intraocular lenses (MIOLs) of different designs have been used for more than 20 years in modern cataract surgery. The first IOLs were either refractive 2-3-zone designs or of diffractive concept. All MIOL types, regardless of manufacturer, show reduced contrast sensitivity and increased glare for years. Nevertheless, even first-generation MIOL patients had very good functional results when patient selection, IOL calculation, and surgical techniques were appropriate. Today's gold standard is foldable, aspherical diffractive, or refractive MIOLS. Advancements in technology allow the possibility that MIOLs will be used for aphakia correction as well as presbyopia correction.


Asunto(s)
Lentes Intraoculares/normas , Óptica y Fotónica , Diseño de Prótesis , Refracción Ocular , Errores de Refracción/terapia , Astigmatismo/etiología , Astigmatismo/terapia , Sensibilidad de Contraste , Humanos , Presbiopía/terapia , Estándares de Referencia
13.
Ophthalmologe ; 104(12): 1024-31, 2007 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-18046556

RESUMEN

Patients with astigmatism (e.g. regular or keratoplasty-induced astigmatism) who undergo cataract surgery or refractive lens exchange with a standard monofocal IOL are often disappointed. Toric IOLs (T-IOLs) are, therefore, an excellent alternative for this condition. T-IOLs are now available from companies such as Alcon, Acri, Tec, Humanoptics, Wavelight, Rayner and Staar. Apart from Alcon and Staar who only produce T-IOLs with a fixed torus, all these produce customised lenses. The calculations needed for production of the T-IOLs are generally done by the companies and are based on the corneal astigmatism. T-IOLs have shown good rotational stability and good functional results. Corneal astigmatism can still be measured postoperatively, as it is corrected inside the eye. The referring ophthalmologist should exercise discretion when prescribing spectacles after surgery of this kind.


Asunto(s)
Astigmatismo/rehabilitación , Astigmatismo/cirugía , Extracción de Catarata , Catarata/terapia , Implantación de Lentes Intraoculares/métodos , Lentes Intraoculares , Humanos , Diseño de Prótesis
14.
Eur J Ophthalmol ; 17(3): 327-31, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17534811

RESUMEN

PURPOSE: To evaluate and compare anterior chamber depth (ACD) measurements using Orbscan II (Bausch & Lomb, Rochester, NY) and IOLMaster (Carl Zeiss Meditec AG, Jena, Germany). METHODS: In this prospective clinical study, the authors measured ACD of 145 phakic eyes of 30 healthy volunteers and 115 patients using Orbscan II and IOLMaster. Average patient age was 52.9+/-19.4 (range 16 to 87) years. ACD was evaluated from corneal epithelium to anterior lens surface. Additionally, axial length (AL) was measured using the Zeiss IOLMaster to calculate the regression coefficient between AL and ACD. RESULTS: Mean ACD was 3.35+/-0.43 mm (range 2.01 mm to 4.37 mm) using Orbscan II and 3.36+/-0.41 mm (range 2.09 mm to 4.24 mm) using IOLMaster. Mean total axial length was 24.04 mm +/- 2.1 mm (range 20.7 mm to 31.41 mm). The linear regression coefficient of ACD between both methods was R=0.95. ACD and AL correlated only slightly (R=0.57). The Spearman coefficients of rank correlation were 0.94 and 0.61, respectively. A p value less than 0.01 (paired Wilcoxon test) was considered statistically significant. However, a significant difference was not calculated comparing ACD measurements using both systems and the Bland-Altman-Plot showed 95% of the differences ranging between 0.25 and -0.27 mm. CONCLUSIONS: Regarding clinical application, both systems seem to be equally good and interchangeable in clinical practice in terms of ACD evaluation.


Asunto(s)
Cámara Anterior/anatomía & histología , Topografía de la Córnea/métodos , Técnicas de Diagnóstico Oftalmológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biometría , Humanos , Persona de Mediana Edad , Estudios Prospectivos
15.
Eye (Lond) ; 21(6): 697-701, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16498433

RESUMEN

PURPOSE: To evaluate intraocular lens (IOL) power calculation using ray tracing in patients presenting with cataract after excimer laser surgery. METHODS: Ten eyes of seven consecutive patients who presented for cataract surgery following excimer laser treatment without any pre-refractive biometry data were enrolled in this prospective clinical study. Preoperatively, IOL power calculation was performed using a ray tracing software called OKULIX. Keratometry data (C-Scan) were imported and axial length (IOLMaster) was entered manually. Accuracy of IOL power calculation was investigated by subtracting attempted and achieved spherical equivalent. RESULTS: Mean spherical equivalent was -3.51+/-2.77 D (range -10.38 to -0.5 D) preoperatively and -1.01+/-1.08 D (range -2.5 to +0.75 D) postoperatively. Mean error was 0.31+/-0.84 D, mean absolute error was 0.74+/-0.46 D, and IOL calculation errors ranged from -1.39 to +1.47 D. A total of 40% of eyes were within +/-0.5 D, 70% within +/-1.0 D, and 100% within +/-1.5 D. Three eyes with corneal radii over 10 mm showed calculation errors exceeding +/-1.0 D. Mean best-corrected visual acuity increased from 20/60 to 20/30 postoperatively. CONCLUSIONS: IOL power calculation after excimer laser surgery can be difficult, especially when pre-refractive keratometry values are not available. In these cases, ray tracing combined with corneal topography measurements provides reliable and satisfactory postoperative results. However, it is advisable to be careful when calculating IOL power for eyes with corneal radii exceeding 10 mm because of slightly higher prediction errors.


Asunto(s)
Lentes Intraoculares , Queratectomía Fotorrefractiva , Refracción Ocular , Anciano , Biometría/métodos , Topografía de la Córnea/métodos , Humanos , Láseres de Excímeros , Persona de Mediana Edad , Optometría/métodos , Facoemulsificación , Cuidados Preoperatorios/métodos , Estudios Prospectivos , Programas Informáticos , Resultado del Tratamiento , Agudeza Visual
16.
Ophthalmologe ; 103(8): 661-6, 2006 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-16835791

RESUMEN

Modern cataract surgery has advanced tremendously over the past 20 years. Improved surgical techniques, as well as improved implant materials and designs, have enlarged patient profiles and indications not only for cataract surgery, but also for refractive lens exchange surgery. This has also created much higher patient expectations. The loss of accommodation is a loss of quality of life for presbyopic and especially young pseudophakic patients. Multifocal intraocular lenses (MIOL) have been implanted since 1986, starting with 2-3 zone refractive and diffractive designs. Due to the surgical techniques available at that time, MIOL decentration and surgically induced astigmatism were possible complications. In addition, reduced contrast perception and increased glare were common problems of MIOL because of their optical principles. New developments in this field in recent years such as the folding, multizonal, progressive refractive MIOL and aspheric diffractive MIOL in combination with improved surgical techniques have overcome those initial problems. Therefore, modern MIOL (and in the future also accommodative IOL) can be considered not only for the correction of aphakia but also for refractive purposes.


Asunto(s)
Implantación de Lentes Intraoculares/métodos , Lentes Intraoculares , Presbiopía/rehabilitación , Presbiopía/cirugía , Ajuste de Prótesis/métodos , Humanos , Satisfacción del Paciente , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina , Presbiopía/diagnóstico , Diseño de Prótesis
17.
Klin Monbl Augenheilkd ; 223(7): 559-67, 2006 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-16855938

RESUMEN

Secondary cataract or posterior capsule opacification (PCO) is still the most frequent long-term complication of cataract surgery. Tremendous advances have been made, especially during the last 10 to 15 years, in terms of surgical techniques and improvement of implant technology. However, the problem of proliferation and migration of lens epithelial cells (LECs) postoperatively has not yet been solved completely although we know that a sharp optic edge of intraocular lenses (IOL) combined with hydrodissection, complete overlapping of capsulorhexis and IOL-optic as well as capsular bending reduce PCO formation significantly. In the 1980 s, investigators like Hartmann et al. began with the application of pharmacological substances in-vitro in order to successfully prevent LECs from proliferating and migrating. Cytostatic drugs, steroids, non-steroidal antiphlogistics, adhesion inhibitors, heparin, lidocaine, suramin, immunotoxins, photodynamic therapy and osmotic effective solutions were tested. In several studies different drug delivery systems were investigated in order to provide a longer and more effective impact on LECs. However, the in-vivo use has been viewed critically since the selective targeting of LECs was not possible and serious damage to the surrounding tissue had to be considered. Recently, the development of the PerfectCapsule System for vacuum-sealed capsule irrigation allows the selective targeting of LECs inside the capsular bag. This survey gives an update on past, current and future means and trends to reduce or prevent PCO formation pharmacologically.


Asunto(s)
Antiinflamatorios/administración & dosificación , Extracción de Catarata/efectos adversos , Catarata/tratamiento farmacológico , Catarata/prevención & control , Fotoquimioterapia/métodos , Esteroides/administración & dosificación , Catarata/etiología , Humanos , Soluciones Oftálmicas/administración & dosificación , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina , Resultado del Tratamiento
18.
Br J Ophthalmol ; 90(8): 971-4, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16687454

RESUMEN

BACKGROUND: Owing to the improvement of modern intraocular lenses (IOLs) in terms of design and material, posterior capsule opacification (PCO) usually takes 2-3 years to develop. Thus, long term clinical evaluation of new implants is important. METHODS: As part of a prospective, non-randomised FDA trial, the Rayner Centerflex, a foldable hydrophilic acrylic, single piece IOL was implanted in one eye of 83 patients (mean age 73.5 (SD 7.0) years). Over 3 years postoperatively, a standardised FDA protocol concerning IOL safety and efficacy was followed including evaluation of spherical equivalent (SE), best corrected distance visual acuity (BCDVA), endothelial cell count (ECC), flare meter values, PCO development, and anterior capsule shrinkage. RESULTS: Postoperatively, mean SE was stable ranging between -0.3D and 0.17D. After 1-2 months, all patients achieved a BCDVA of 20/40 or better. At 3-6 months postoperatively, mean ECC decreased from 2612 (SD 346) cells/mm2 to 2380 (316) cells/mm2. Mean PCO score for the entire optic increased from 0.20 (0.20) months (3-6 months postoperatively) to 0.87 (0.57) resulting in a Nd:YAG rate of 29.41% after 3 years. No anterior capsule shrinkage was found. CONCLUSION: The Centerflex showed excellent functional results, low values for endothelial cell loss and inflammatory signs, and no anterior capsule shrinkage. PCO formation was higher compared to other IOLs, which could be explained by the incomplete sharp edge at the optic-haptic junctions representing an "Achilles' heel" for cell ingrowth.


Asunto(s)
Lentes Intraoculares , Resinas Acrílicas , Anciano , Anciano de 80 o más Años , Materiales Biocompatibles , Catarata/etiología , Células Endoteliales/patología , Femenino , Estudios de Seguimiento , Humanos , Terapia por Láser , Cápsula del Cristalino/patología , Cápsula del Cristalino/cirugía , Masculino , Ensayo de Materiales , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Prospectivos , Diseño de Prótesis , Recurrencia
19.
Ophthalmologe ; 103(1): 25-9, 2006 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-15983779

RESUMEN

BACKGROUND: At the Department of Ophthalmology, Heidelberg, Germany, posterior capsule opacification (PCO) of a silicone and an acrylic intraocular lens (IOL) with a sharp optic edge design was evaluated. PATIENTS AND METHODS: In a prospective study either the AMO ClariFlex silicone IOL or the Sensar AR40e hydrophobic acrylic IOL were implanted in 47 patients following uneventful phacoemulsification. Mean patient age was 76.2+/-7.8 (ClariFlex) and 73.4+/-12.9 years (AR40e), respectively. The mean follow-up time was 19.7+/-5.34 in the ClariFlex and 21.9+/-1.89 months in the AR40e group. PCO development was evaluated postoperatively using the EPCO 2000 analysis software (scale 0-4). Areas of interest were the total IOL optic, the central 3-mm zone as well as the capsulorhexis. RESULTS: In both groups, all patients achieved a BCVA of 20/32 (AR40e) and 20/25 (ClariFlex), respectively. There was a very low incidence of PCO development with a mean EPCO score of 0.07+/-0.2 (ClariFlex and 0.15+/-0.2 (AR40e). Within the 3-mm zone and the capsulorhexis, there was a tendency for even lower EPCO scores in both groups. We calculated a statistically significant difference for the two lens materials for all investigated IOL areas (Wilcoxon's test, p<0.05). CONCLUSION: Both IOLs with a sharp edge design showed good functional results, a stable position in the capsular bag as well as a low incidence of PCO development. However, the silicone IOL showed statistically significantly lower PCO scores.


Asunto(s)
Resinas Acrílicas , Opacidad de la Córnea/epidemiología , Reacción a Cuerpo Extraño/epidemiología , Lentes Intraoculares/estadística & datos numéricos , Siliconas , Anciano , Anciano de 80 o más Años , Comorbilidad , Opacidad de la Córnea/diagnóstico , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Reacción a Cuerpo Extraño/diagnóstico , Reacción a Cuerpo Extraño/prevención & control , Alemania/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Óptica y Fotónica/instrumentación , Evaluación de Resultado en la Atención de Salud , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento
20.
Ophthalmologe ; 102(6): 579-86, 2005 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-15889259

RESUMEN

Even though tremendous advances have been made especially during the last 10-15 years in terms of surgical techniques and improvement of implant technology, posterior capsule opacification (PCO) still remains a serious long-term complication. New clinical and laboratory studies (especially of autopsy eyes) have improved our understanding of how IOL design and material influence PCO. Sharp edge optic designs of IOLs of various materials have been shown to significantly reduce secondary cataract. The application of pharmacological substances selectively into the capsular bag is now possible due to the development of the PerfectCapsule System for vacuum-sealed capsule irrigation. Major advances in other areas of biotechnology and immunology including gene therapeutic methods offer totally new approaches for the future in the elimination of lens epithelium cells from the capsular bag. This survey gives an update on current and future means and trends to reduce or prevent PCO formation.


Asunto(s)
Materiales Biocompatibles/efectos adversos , Catarata/etiología , Catarata/prevención & control , Reacción a Cuerpo Extraño/etiología , Reacción a Cuerpo Extraño/prevención & control , Lentes Intraoculares/efectos adversos , Diseño de Prótesis/métodos , Falla de Prótesis , Catarata/patología , Análisis de Falla de Equipo , Reacción a Cuerpo Extraño/patología , Humanos , Ensayo de Materiales
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