RESUMO
PURPOSE: To prospectively measure the scotopic pupil diameter in a normal population and to compare 2 infrared pupillometers for these measurements. SETTING: Johann Wolfgang Goethe-University, Department of Ophthalmology, Frankfurt am Main, Germany. METHODS: The Colvard infrared pupillometer was compared to the Video Vision Analyzer (VIVA) infrared pupillometer under scotopic light conditions in 33 participants (aged 19 to 55 years). Reliability was assessed by 2 independent examiners (E1, E2). Statistical analysis was performed using a comparison method by Bland and Altman. RESULTS: Mean pupil diameter was 6.16 mm +/- 1.20 (SD) (range 3.20 to 9.00 mm) with all measurements taken under scotopic illumination. The mean scotopic pupil diameter was 6.08 +/- 1.16 mm (range 3.2 to 8.4 mm) with the Colvard pupillometer and 6.24 +/- 1.28 mm (3.5 to 9.0 mm) with the VIVA pupillometer. The mean differences between the Colvard and VIVA were -0.27 mm (E1) and -0.05 mm (E2). Limits of agreement ranged from 1.4 (Colvard) to 2.4 (VIVA). The coefficients of repeatability ranged from 0.7 (Colvard) to 1.1 (VIVA). CONCLUSIONS: A mean scotopic pupil diameter of 6.15 mm with a maximal pupil size of 9.00 mm can be expected in a normal population; this should be considered in refractive corneal and refractive lens surgery. Measurements with the Colvard pupillometer were more reliable and precise than those with the VIVA pupillometer.
Assuntos
Adaptação à Escuridão/fisiologia , Técnicas de Diagnóstico Oftalmológico/instrumentação , Raios Infravermelhos , Pupila/fisiologia , Gravação em Vídeo , Adulto , Envelhecimento/fisiologia , Desenho de Equipamento , Cor de Olho , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Valores de ReferênciaRESUMO
PURPOSE: The results of photorefractive/photoastigmatic refractive keratectomy (PRK/PARK) were compared between two patient groups treated consecutively with either broad-beam or scanning-spot technology. PATIENTS AND METHODS: PRK/PARK was performed with a broad-beam excimer laser VISX 20/20 in 46 eyes and with the scanning-spot laser system Keracor 217 in 49 eyes. Preoperative spherical equivalent (subjective manifest refraction) was < or =-6.0 diopter in both groups. Safety, efficacy, predictability, stability, and complications were investigated after 1,4 and 12, months postoperatively. RESULTS: In the broad-beam laser group no eye lost two or more lines of best-corrected visual acuity;in the scanning-spot laser group one eye lost two lines 12 months postoperatively. Efficacy, predictability, and stability were comparable between the two groups. CONCLUSIONS: Both the broad-beam and the scanning-spot laser provided good results after PRK/PARK for low myopia and myopic astigmatism. This study found no fundamental differences between the two laser systems.
Assuntos
Astigmatismo/cirurgia , Miopia/cirurgia , Ceratectomia Fotorrefrativa/instrumentação , Adulto , Feminino , Seguimentos , Humanos , Lasers de Excimer , Masculino , Pessoa de Meia-Idade , Refração Ocular , Resultado do TratamentoRESUMO
PURPOSE: Recently laser-in-situ-keratomileusis (LASIK) has been increasingly used to correct refractive errors. The purpose of this investigation was to evaluate the safety, efficacy, predictability, stability and complications using the scanning spot excimer LASIK technology. PATIENTS AND METHODS: The results of 100 consecutive LASIK operations carried out between 2/1998 and 2/1999 on 60 patients (mean age 37 years, range 20-55 years) have been evaluated. The Hansatome microkeratome with a superior hinge (flap diameter: 9.5 mm) and a scanning spot excimer laser (Technolas C-Lasik 217) were used in all cases. The mean spherical equivalent of the subjective manifest refraction was -6.96 +/- 2.87 diopters (D), the mean sphere was -6.47 +/- 2.71 D and the mean astigmatism was -0.98 +/- 0.94 D. In 6% of the eyes preoperative visual acuity was not better than 20/40. Examinations were performed preoperatively, after 1 and 7 days, after 1,4 and 12 months. Safety, efficacy, predictability, stability and complications were calculated using the datagraph software (version 1.11). RESULTS: All 100 eyes were examined after 1 day and 1 week, 96 after 1 month, 95 after 4 months and 92 after 1 year. Following 1 year none of the eyes lost 2 or more lines of best corrected visual acuity, 99% were within +/- 1 line and 1% gained 2 lines (safety index 1.03). In 92% of all eyes an uncorrected visual acuity of > or = 0.5 was reached, in 77% > or = 0.8 and in 51% > or = 1.0 (efficacy index 0.89). For 60 eyes (65.21%) a refractive correction of +/- 0.5 D was necessary, for 82 eyes (89.13%) +/- 1.0 D and for 91 eyes (98.91%) +/- 2.0 D. The mean spherical equivalent after 1 year was -0.15 +/- 1.31 D. Between 1 and 12 months a mean regression of -0.14 D occurred. On the request of the patients, 5 eyes were retreated during the study period for under- or over-correction. Complications due to the microkeratome did not occur. Corneal infections were not observed, a diffuse lamellar keratitis (DLK) was seen in 12 cases, but all cases healed with no loss of visual acuity. In 7 eyes a slight decentration of the ablation was observed using corneal topography, which in one case caused an increase in glare sensitivity. CONCLUSIONS: LASIK with superior hinge and scanning spot excimer photoablation is suitable for the correction of myopia (up to a maximum of -12 D) and for myopic astigmatism (up to a maximum of -5 D). The refractive results showed a high stability during the 12-month study period but there is still room for improvement of the predictability.
Assuntos
Astigmatismo/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ , Miopia/cirurgia , Adulto , Fatores Etários , Seguimentos , Humanos , Complicações Intraoperatórias , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Fatores de TempoRESUMO
BACKGROUND: For the correction of refractive errors lenticular procedures are increasingly used in addition to corneal refractive surgery. One of those techniques is the implantation of intraocular lenses into phakic eyes (pIOL). Due to the close neighborhood of the implant to delicate intraocular structures, exact positioning and high postoperative stability are required. Scheimpflug photography has been shown to be a suitable instrument for the biometry of the anterior eye segment and the examination of IOL position. PATIENTS AND METHODS: Four anterior chamber phakic IOLs (pIOLs) (Bausch & Lomb NuVita) and 7 posterior chamber pIOLs (Staar ICL) were examined 1 week, 1 month and 3-6 months following implantation. At each examination 1 Scheimpflug slit image and 1 infrared retroillumination image were taken using the anterior eye segment analysis system EAS-1000 (Nidek Co., Gamagori, Japan). Evaluation of the images was performed with a personal computer and the software provided by the manufacturer. The distance of the pIOL to cornea and human lens was calculated and incidence and amount of pIOL rotation around the optical axis and potential crystalline lens opacification were assessed. RESULTS: The distance between the anterior chamber pIOL and the cornea 1 week after implantation was 1.61 +/- 0.10 mm. The distances between the myopic posterior chamber pIOL and the human lens were 0.34 +/- 0.11 mm and between the hyperopic posterior chamber pIOL and the human lens 0.26 and 0.29 mm, respectively. The values were constant over a period of 3-6 months. The pIOL showed no movement or change of position around the optical axis. There was no detectable cataract formation in the human lens. CONCLUSIONS: All implanted phakic anterior and posterior chamber IOLs showed a stable position in the eye within the observation period. Scheimpflug photography is proved to be a useful technique for the postoperative evaluation of the positioning of phakic IOLs.
Assuntos
Hiperopia/cirurgia , Implante de Lente Intraocular/métodos , Miopia/cirurgia , Fotografação/métodos , Câmara Anterior , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Implante de Lente Intraocular/efeitos adversos , Fotografação/instrumentação , Resultado do TratamentoRESUMO
BACKGROUND: Photorefractive keratectomy (PRK) is an accepted procedure to correct myopia in Germany. The purpose of this study was to evaluate photoastigmatic refractive keratectomy (PARK) for myopic astigmatism. MATERIAL AND METHODS: PARK using the VISX 20/20 excimer laser was performed in 50 eyes of 36 patients (25 female, 16 male) aged 22 to 68 years (mean 38 +/- 10 years) in the period of 1995 to 1996. Retrospective evaluation was done after dividing the patients into three astigmatic groups between -0.5 diopters (D) and -1.5 D (group I, n = 28), between -1.75 D and -3.0 D (group II, n = 16) und between -3.25 D and -5.5 D (group III, n = 6). The correction of myopic astigmatism was assessed concerning the criteria safety, efficacy, predictability and stability. Mean follow-up was 12 months (8-15 months). RESULTS: Seventy-eight % of all eyes achieved an uncorrected visual acuity of > 0.5. Sixty-eight % of the eyes were within +/- 1.0 D of the desired correction. Loss of 2 or more lines of best corrected visual acuity occurred in 6 eyes (12.0%). We observed in group I an astigmatic reduction of 36.0%, in group II of 66.5% and in group III of 68.0%. The surgically induced astigmatism was calculated with 1.29 +/- 1.0 D. Mean axis rotation of the refractive cylinder was 22.12 +/- 23.05 degrees. CONCLUSIONS: PARK using the VISX 20/20 excimer laser is an acceptable procedure to correct myopic astigmatism. However, the study revealed that astigmatic reduction with a broad beam laser is not yet perfect in terms of efficacy, predictability and safety.