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- ItemAcesso aberto (Open Access)Avaliação do desempenho visual da lente intraocular difrativa multifocal - Zeiss AT Lisa 809 MTM(Sociedade Brasileira de Oftalmologia, 2014-04-01) Vianna, Lucas Monferrari Monteiro [UNIFESP]; Oliveira, Filipe de [UNIFESP]; Pedro, Abujamra [UNIFESP]; Jung, Liang [UNIFESP]; Brenner, Luis Felipe [UNIFESP]; Yogi, Milton [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Purpose:To evaluate the visual function of patients with bilateral implantation of multifocal diffractive IOL AT Lisa 809MTM by visual acuity with and without correction, contrast sensitivity curve, defocus curve and visual function questionnaire (39 VQF).Methods:Interventional clinical prospective study, which evaluated the results of 20 eyes of 10 patients who underwent phacoemulsification and IOL implantation between february and june 2012.Results:The average of residual postoperative ametropia was 0.05 ± 0.42 (-0.75 to +1.25 D) spherical diopters and -0.30 ± 0.42 (0 to -1.25 D) cylindrical diopters. In the mono and binocular defocus curve, the best visual acuity was obtained with 0.00 D of defocus (far VA). The second peak was obtained with -3.00 D (near vision at 33 cm) and among these peaks, it was observed a loss of visual performance with -2.00 D, which corresponds to intermediate vision at 50 cm. Contrast sensitivity was similar to those reported in the literature with this type of IOL, both with and without glare, and is shown in the figures. The visual function questionnaire (VFQ-39) had a mean value of 91.91 + - 6.82.Conclusion:The diffractive multifocal IOL-AT LISA 809M presented results consistent with the literature as measured by tests of visual acuity with and without optical correction, contrast sensitivity curve, defocus curve and visual function questionnaire (39 VQF).
- ItemAcesso aberto (Open Access)Lente de contato de material híbrido em pacientes com ceratocone e astigmatismo miópico composto(Conselho Brasileiro de Oftalmologia, 2007-03-01) Leal, Fernando [UNIFESP]; Lipener, César [UNIFESP]; Chalita, Maria Regina [UNIFESP]; Uras, Ricardo [UNIFESP]; Campos, Mauro Silveira de Queiroz [UNIFESP]; Hofling-Lima, Ana Luisa [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)PURPOSE: To evaluate comfort and visual performance in relation to two different used contact lens types: hybrid material (HM) and rigid-gas-permeable (RGP), in patients with regular myopic astigmatism and with keratoconus. METHODS: A randomized, double masked, prospective study of 22 patients with the diagnosis of myopic astigmatism (8 with myopic astigmatism and 14 with keratoconus) was conducted. Fifteen patients were female and 7 were male, and mean age was: 32.13 ± 8.12 years. In one of the eyes a rigid-gas-permeable contact lens was adapted (DK 30), and in the other a hybrid material contact lens was adapted (DK 23). All patients were submitted to the following tests: measurement of comfort level by means of the analogical visual scale, tear break-up time, best corrected visual acuity with the Bailey-Lovie scale adapted for 4 meters, functional acuity contrast test (FACT) and wavefront analysis. RESULTS: In relation to comfort, there was no association with the evaluated contact lens type (p=0.350). There was a variation in comfort level during the first 7 days. The visual acuity increased between the 7th and the 15th day of adaptation. Visual acuity stabilized right after this period. The visual acuity did not show differences in relation to the studied lens type. It was verified that there was no difference in the tear break-up time (p=0.989) in relation to the studied lenses type and there was a decrease in the tear break-up time (p=0.001) when we compared the measurement before the use of the lenses and 2 months after their use. There was no difference in contrast sensitivity in the used lens type and between each type and the use of glasses (p<0.047). High order aberrations decreased significantly when comparing patients with and without contact lenses, except for spherical and coma aberrations (p=0.394). CONCLUSION: Comfort and visual performance when comparing hybrid material and rigid-gas-permeable contact lenses did not show any significant difference in the patients or when compared separately in regular myopic astigmatism and in keratoconus patients.
- ItemAcesso aberto (Open Access)Resultados preliminares de um sistema computadorizado e estereoscópico para pupilometria in vivo(Conselho Brasileiro de Oftalmologia, 2008-12-01) Carvalho, Luis Alberto Vieira de [UNIFESP]; Paranhos Junior, Augusto [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Instituto Israelita de Ensino e Pesquisa Albert Einstein Pesquisa ClínicaPURPOSE: We developed a digital system with accommodation capacities for measurement of the diameter and shape of the in vivo pupil for 10 different levels of illumination intensity, varying from mesopic to photopic. METHODS: An optical system for conjugating images from an infrared and white light illuminated pupil was designed and mounted using an ophthalmoscope helmet and a typical diving mask as support for a high-resolution and sensitivity CCD. Using an IBM compatible computer sequences of video in AVI format were digitized for several seconds at a mean rate of 30 Hz. Algorithms using principles of image processing were implemented for detection of the pupil edges. RESULTS: We present preliminary results of this system for a voluntary patient. Data for the horizontal (x) and vertical (y) central position and for the diameter of the pupil were then exported to files that could be read by typical spread sheet programs (Excel). CONCLUSIONS: In this manner, precise data can be obtained stereoscopically (for both pupils at the same time) for any patient, given that the accommodation process is guaranteed by using a white LED virtual mire located 6 meters from the patient's eye. An electronic board precisely controls the level of illumination. We believe here developed instrument may be useful in certain ophthalmic practices where precise pupil geometric data are needed.