Abstract:
INTRODUCTION:The method for measuring intraocular pressure using the Corvis tonometer provides a sequence of images of corneal deformation. Deformations of the cornea are recorded using the ultra-high-speed Scheimpflug camera. This paper presents a new and reproducible method of analysis of corneal deformation images that allows for automatic measurements of new features, namely new three parameters unavailable in the original software. MATERIAL AND METHOD:The images subjected to processing had a resolution of 200 × 576 × 140 pixels. They were acquired from the Corvis tonometer and simulation. In total 14,000 2D images were analysed. The image analysis method proposed by the author automatically detects the edge of the cornea and sclera fragments. For this purpose, new methods of image analysis and processing proposed by the author as well as those well-known, such as Canny filter, binarization, median filtering etc., have been used. The presented algorithms were implemented in Matlab (version 7.11.0.584-R2010b) with Image Processing toolbox (version 7.1-R2010b) using both known algorithms for image analysis and processing and those proposed by the author. RESULTS:Owing to the proposed algorithm it is possible to determine three parameters: (1) the degree of the corneal reaction relative to the static position; (2) the corneal length changes; (3) the ratio of amplitude changes to the corneal deformation length. The corneal reaction is smaller by about 30.40% compared to its static position. The change in the corneal length during deformation is very small, approximately 1% of its original length. Parameter (3) enables to determine the applanation points with a correlation of 92% compared to the conventional method for calculating corneal flattening areas. The proposed algorithm provides reproducible results fully automatically within a few seconds/per patient using Core i7 processor. CONCLUSIONS:Using the proposed algorithm, it is possible to measure new, additional parameters of corneal deformation, which are not available in the original software. The presented analysis method provides three new parameters of the corneal reaction. Detailed clinical studies based on this method will be presented in subsequent papers.
journal_name
Biomed Eng Onlinejournal_title
Biomedical engineering onlineauthors
Koprowski Rdoi
10.1186/1475-925X-13-150subject
Has Abstractpub_date
2014-11-19 00:00:00pages
150issn
1475-925Xpii
1475-925X-13-150journal_volume
13pub_type
杂志文章abstract:BACKGROUND:In spite of numerous non-invasive examinations the "gold clinical standard" of cardiac output measurements is the invasive pulmonary artery catheterization by means of the Swan-Ganz catheter and the application of the thermodilution method to estimate the blood flow. The results obtained by means of thermodi...
journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-11-24
更新日期:2012-05-20 00:00:00
abstract:BACKGROUND:In a typical electrophysiological experiment, especially one that includes studying animal behavior, the data collected normally contain spikes, local field potentials, behavioral responses and other associated data. In order to obtain informative results, the data must be analyzed simultaneously with the ex...
journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/s12938-017-0419-7
更新日期:2017-11-13 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-13-S2-S5
更新日期:2014-01-01 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章,评审
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journal_title:Biomedical engineering online
pub_type: 杂志文章
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journal_title:Biomedical engineering online
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journal_title:Biomedical engineering online
pub_type: 杂志文章
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journal_title:Biomedical engineering online
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更新日期:2011-01-26 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
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更新日期:2015-08-07 00:00:00
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journal_title:Biomedical engineering online
pub_type: 评论,信件
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journal_title:Biomedical engineering online
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更新日期:2017-07-14 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/s12938-019-0729-z
更新日期:2019-11-14 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-13-138
更新日期:2014-09-23 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-6-23
更新日期:2007-06-26 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-11-80
更新日期:2012-10-25 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-12-97
更新日期:2013-09-28 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/s12938-018-0458-8
更新日期:2018-03-02 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/s12938-017-0386-z
更新日期:2017-07-29 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/s12938-015-0112-7
更新日期:2015-12-21 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章,评审
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journal_title:Biomedical engineering online
pub_type: 杂志文章
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更新日期:2007-09-26 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
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journal_title:Biomedical engineering online
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更新日期:2019-01-24 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
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更新日期:2013-02-22 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/s12938-018-0433-4
更新日期:2018-01-25 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-9-59
更新日期:2010-10-12 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-13-44
更新日期:2014-04-16 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/1475-925X-6-19
更新日期:2007-05-31 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章
doi:10.1186/s12938-020-00796-x
更新日期:2020-07-31 00:00:00
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journal_title:Biomedical engineering online
pub_type: 杂志文章,评审
doi:10.1186/s12938-020-00826-8
更新日期:2020-11-09 00:00:00