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1.
Int Ophthalmol ; 33(6): 645-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23512683

RESUMEN

An experimental study to measure the heat profile of the phacoemulsification (phaco) tip using standard continuous phaco and hyperpulse phaco with and without waveform power modulation in the Millennium Microsurgical System with Custom Control Software (CCS). The phaco tip was imaged in air using a thermal camera. The highest temperature was measured 15 s after application of phaco power. Continuous, hyperpulse and waveform power modulations of the Millennium Microsurgical System were used with different power settings (20, 50 and 100 %) and duty cycles (40, 60 and 90 %), with the irrigation turned on and off. Using continuous phaco with the irrigation on, the phaco tip temperature remains <28.0 °C. With irrigation off, the temperature is higher compared to irrigation on but still remains <45.0 °C. Comparing the temperatures for all three power modulations when irrigation is on, at each phaco power and duty cycle setting, the temperature of the phaco tip is highest with continuous phaco, followed by hyperpulse with rise time 1, then hyperpulse with rise time 2. When irrigation is off, the highest temperatures are recorded using the hyperpulse with rise time 2, followed by continuous phaco, then hyperpulse with rise time 1. Hyperpulse and waveform modulations reduce heat generation compared to the continuous mode when irrigation is turned on. Lower duty cycles and lower ultrasound power produce less heat at the phaco tip.


Asunto(s)
Calor , Facoemulsificación/instrumentación , Rayos Infrarrojos , Facoemulsificación/métodos , Fotograbar/métodos , Irrigación Terapéutica
13.
BMJ Open ; 9(12): e028811, 2019 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-31818832

RESUMEN

INTRODUCTION: Diabetic retinopathy (DR) is a common microvascular complication of diabetes mellitus and the leading cause of impaired vision in adults worldwide. Early detection and treatment for DR could improve patient outcomes. Traditional methods of detecting DR include the gold standard Early Treatment Diabetic Retinopathy Study seven standard fields fundus photography, ophthalmoscopy and slit-lamp biomicroscopy. These modalities can be expensive, difficult to access and require involvement of specialised healthcare professionals. With the development of mobile phone technology, there is a growing interest in their use for DR identification as this approach is potentially more affordable, accessible and easier to use. Smartphones can be employed in a variety of ways for ophthalmoscopy including the use of smartphone camera, various attachments and artificial intelligence for obtaining and grading of retinal images. The aim of this scoping review is to determine the diagnostic test accuracy of various smartphone ophthalmoscopy approaches for detecting DR in diabetic patients. METHODS AND ANALYSIS: We will perform an electronic search of MEDLINE, Embase and Cochrane Library for literature published from 2000 onwards. Two reviewers will independently analyse studies for eligibility and assess study quality using the QUADAS-2 tool. Data for a 2⨉2 contingency table will be extracted. If possible, we will pool sensitivity and specificity data using the random-effects model and construct a summary receiver operating characteristic curve. In case of high heterogeneity, we will present the findings narratively. Subgroup analysis and sensitivity analysis will be performed where appropriate. ETHICS AND DISSEMINATION: This scoping review aims to provide an overview of smartphone ophthalmoscopy in DR identification. It will present findings on the accuracy of smartphone ophthalmoscopy in detecting DR, identify gaps in the literature and provide recommendations for future research. This review does not require ethical approval as we will not collect primary data.


Asunto(s)
Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Edema Macular/diagnóstico , Oftalmoscopía/métodos , Teléfono Inteligente , Humanos , Edema Macular/etiología , Proyectos de Investigación , Literatura de Revisión como Asunto , Sensibilidad y Especificidad
20.
Am J Ophthalmol ; 143(1): 90-96, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17098206

RESUMEN

PURPOSE: To describe the loss of light perception and other visual experiences encountered during different stages of laser in situ keratomileusis (LASIK) and to compare patients' experiences between LASIK performed with the Zyoptix XP microkeratome and Intralase laser. DESIGN: Prospective, randomized, self-matched clinical study. METHODS: Forty-one patients (82 eyes) had bilateral LASIK with the corneal flap fashioned by Zyoptix XP microkeratome in one eye and Intralase laser in the other. They were interviewed postoperatively with a standardized questionnaire about their intraoperative visual experiences, including light perception and ability to see the red fixation light. RESULTS: During both vacuum suction and corneal flap fashioning, a higher proportion of eyes in the Zyoptix XP microkeratome group lost light perception compared with the Intralase group (85.4% vs 39.0% and 90.2% vs 61.0%; P < .001 and P = .004, respectively). Patients also saw flashes, various colors, movement, the surgeon's hands or fingers, and the surgeon during surgery, and there was no difference in these visual experiences between the Zyoptix XP microkeratome and Intralase groups. Overall, eight (19.5%) of 41 patients were frightened by their intraoperative visual experiences during LASIK. CONCLUSIONS: Patients retain light perception during most stages of LASIK except during suction and fashioning of the corneal flap, when some are temporarily unable to see. Many also experience various visual sensations intraoperatively, and 19.5% of patients are frightened by their visual experiences.


Asunto(s)
Sustancia Propia/cirugía , Queratomileusis por Láser In Situ/métodos , Miopía/cirugía , Visión Entóptica/fisiología , Percepción Visual/fisiología , Adulto , Femenino , Humanos , Periodo Intraoperatorio , Queratomileusis por Láser In Situ/instrumentación , Luz , Masculino , Satisfacción del Paciente , Estudios Prospectivos , Sensación/fisiología , Colgajos Quirúrgicos , Encuestas y Cuestionarios
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