Computer-assisted echography: statistical analysis of A-mode video echograms obtained by tissue sampling
The A-mode video echograms of ophthalmological equipment are quantitatively analysed while using an online connection to a digital computer. A series of echograms is collected while the examiner carries out slight manual scanning movements with the transducer, thus performing a kind of statistical tissue sampling. The amplitude of the echoes is expressed as a percentage of the maximum display magnitude. The attenuation is estimated by a regression analysis while taking into account the amplifier gain curve of the equipment and is expressed in dB/mm tissue. The relative reflectivity of large structure boundaries is expressed in dB. The texture of tissue echograms is analysed by means of amplitude histograms.
KeywordsComputerised A-mode analysis Echo-opthalmography Quantitative echography tissue characterisation
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