RESUMEN
In this paper, we reply to post-surgical corneal asphericity conclusions made by Dai [Appl. Opt.51, 3966 (2012)]. We deduced, after a theoretical analysis, that the conclusions derived from this analysis are not theoretically or experimentally sound, because the author considers only the Munnerlyn formula for ablation algorithms and not the paraxial Munnerlyn formula, which is widespread in refractive surgery [J. Cataract Refract. Surg.14, 46 (1988)]. We refer to a previous paper published by Jiménez et al. [J. Opt. Soc. Am. A21, 98 (2004)] for a complete analysis on this matter that clarifies some points of confusion in Dai's paper.
Asunto(s)
Algoritmos , Córnea/cirugía , Cirugía Laser de Córnea/métodos , Modelos Biológicos , HumanosRESUMEN
In this work, we evaluate the impact of induced aniseikonia on stereopsis. For this, we determined the disparity range (maximum disparity), a parameter related to the size of the physical region that can be perceived stereoscopically. A significant decline in the disparity range was detected with aniseikonia induced by size lenses of 3% for five of the seven observers tested; 5% was necessary for the other two observers. The data indicate the influence of aniseikonia in stereopsis and the need to minimize such impact. These results may be useful in surgical processes such as the correction of pseudophakic patients and refractive surgery in which aniseikonia can be induced to alter the binocular function of the patient.
Asunto(s)
Aniseiconia/fisiopatología , Percepción de Profundidad , Estimulación Luminosa/métodos , Adulto , HumanosRESUMEN
A system that enables the automatic measurement of cardiac rhythm and the quantity of oxygen in the blood has been designed, constructed, and patented. Equipped with the appropriate software, this system registers this information and represents it numerically, in the form of a graph, which can then be printed as a detailed record of cardiac rhythm. This system aids in the determination of cardiac pathologies, and also enables the information to be sent to medical professionals to perform telediagnosis. The apparatus is based on the measurement (sampling) of noninvasive medical parameters. The apparatus is intended to cover a broad range of requirements and needs, as can be used by medical professionals (to detect pathologies related to the pumping and circulation of blood in the body) as well as by lay people who might wish to monitor or gain information concerning their cardiac rhythm and the general functioning of their heart. Thus, the system is designed to be clear and concise in its information as well as easy to use, especially for people unrelated to the medical profession. The way to constructing this system is explained in detail.
Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Frecuencia Cardíaca , Microcomputadores , Óptica y Fotónica , Telemedicina/métodos , Electrocardiografía , Humanos , Oxígeno/sangre , Valores de ReferenciaRESUMEN
In the present work, we use random-dot stereograms to test a possible relationship between associated phoria and stereopsis. We determined, using a modified constant-stimulus method, the disparity range that indicates the maximum range at which stereoscopic correspondence can be achieved. A total of 27 observers took part in the experiment. The value of the disparity range as a function of the associated phoria (measured with a Mallet unit) seems to indicate that greater associated phoria (fixation disparity) correlates with a deterioration in stereoscopic vision, reducing the disparity range and therefore the space region in which stereoscopic vision can be attained.