Siddharth K Karthikeyan, Swaminathan M Sundaram, Ramesh S Ve, Donson D Souza, Sayantan Biswas, Mayur U Shetty
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引用次数: 0
Abstract
Significance: A snapshot intraocular pressure (IOP) is ineffective in identifying the IOP peak and fluctuation, especially during sleep. Because IOP variability plays a significant role in the progression of glaucoma, monitoring the IOP, especially during sleep, is essential to capture the dynamic nature of IOP.
Purpose: We aimed to design an ocular pressure estimator (OPE) that can reliably and accurately measure the IOP noninvasively over closed-eyelid condition.
Methods: Ocular pressure estimator works on the principle that the external pressure applied by raising the IOP of the eyeball is transmitted through a compressible septum to the pressure sensor, thus recording the IOP. A fluid-filled pouch with a pressure sensor was placed over a rubber glove mimicking the eyelid (septum), covering the cornea of enucleated goat eyeballs. A pressure-controlled setup was connected to a goat cadaver eye, which was validated by a rebound tonometer. Cannulation of eyeballs through the lower limbus had the least difference from the control setup values documented using rebound tonometer, compared with cannulation through the optic nerve. Intraocular pressures ranging from 3 to 30 mmHg was induced, and the outputs recorded using OPE were amplified and recorded for 10 minutes (n = 10 eyes). We stratified the randomization of the number of times and the induced pressures.
Results: The measurements recorded were found to be linear when measured against an IOP range of 3 to 30 mmHg. The device has excellent reliability (intraclass correlation coefficient, 0.998). The repeatability coefficient and coefficient of variations were 4.24 (3.60 to 4.87) and 8.61% (7.33 to 9.90), respectively. The overall mean difference ± SD between induced IOP and the OPE was 0.22 ± 3.50 (95% confidence interval, -0.35 to 0.79) mmHg across all IOP ranges.
Conclusions: Ocular pressure estimator offers a promising approach for reliably and accurately measuring IOP and its fluctuation noninvasively under a condition mimicking a closed eye.
期刊介绍：
Optometry and Vision Science is the monthly peer-reviewed scientific publication of the American Academy of Optometry, publishing original research since 1924. Optometry and Vision Science is an internationally recognized source for education and information on current discoveries in optometry, physiological optics, vision science, and related fields. The journal considers original contributions that advance clinical practice, vision science, and public health. Authors should remember that the journal reaches readers worldwide and their submissions should be relevant and of interest to a broad audience. Topical priorities include, but are not limited to: clinical and laboratory research, evidence-based reviews, contact lenses, ocular growth and refractive error development, eye movements, visual function and perception, biology of the eye and ocular disease, epidemiology and public health, biomedical optics and instrumentation, novel and important clinical observations and treatments, and optometric education.
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