Adaptive time-gain compensation method for use in ophthalmic ultrasonic measurement equipment

Abstract

The invention discloses an adaptive time-gain compensation method for use in ophthalmic ultrasonic measurement equipment, which comprises: establishing standard time-gain compensation curves of the anterior chamber, lens and vitreous body which are required to be measured in axis oculi length measurement, and storing the standard time-gain compensation curves in a time gain control (TGC) storage; inputting patient information through a man-machine interaction interface in A-type ultrasonic measurement equipment according to clinic examination; performing pre-measurement; allowing the TGC storage to perform adaptive TGC curve fitting automatically according to acquired data to complete the time-gain compensation curves in accordance of the conditions of an individual receiving the examination; and performing official measurement: after the pre-measurement is accomplished, automatically starting to performing the official measurement by using the time-gain compensation curves adaptive to the specific conditions of the person receiving the examination upon the completion of the fitting of the adaptive TGC curves, obtaining the data on the length of the anterior chamber (AC), the thickness of the lens (LEN) and the length of the vitreous body (VITR) and displaying data. The method improves the measurement accuracy of the length (AL) of the axis oculi and provides more accurate data for diagnosis and artificial lens implantation.

Description

technical field [0001] The invention relates to an ultrasonic measurement technology of the A-type eye axis length in ophthalmology. In particular, it relates to an adaptive time-gain compensation method applied in an ophthalmic ultrasonic measurement device capable of improving the measurement accuracy of the axial length of the eye. Background technique [0002] At present, the technology commonly used in medical ultrasonic diagnosis and measurement equipment is the "pulse-echo" detection method, that is, the ultrasonic transducer radiates ultrasonic waves into the human body under the excitation of electric pulses, and then receives the reflected waves of human tissue and converts them into electrical signals for display. , forming a "sonogram". Because different human tissues have different reflection characteristics of ultrasonic waves, and there are differences in the reflected waves between normal tissues and diseased tissues, doctors can provide a basis for clinical...

AI Technical Summary

Problems solved by technology

The compensation curve adopted by the existing "time-gain compensation" technology causes overcompensation to the anterior chamber and the vitreous body, and serious undercompensation to the crystal, resulting in a large difference in the amplitude of the interface reflection wave and increasing the Measurement error

[0016] 2) Individual differences in eyeball structure

[0018] Therefore, the existing "time-gain compensation" technology cannot accurately adapt to the physiological characteristics and individual differences of the eye structure

[0019] According to the probe frequency commonly used in this type of products is 10MHz, its rise time is about 25ns; the existing "time-gain compensation" technology, due to the difference in the amplitude of the reflected wave at the interface, the time difference to reach the trigger threshold can reach 20ns (such as figure 1 shown), calculated according to the average sound velocity of ultrasound in the eye tissue of 1600m / s, the resulting measurement system error can reach 0.032mm

[0020] my country's current effective pharmaceutical industry standard YY0107-2005 "A-Type Ultrasonic Measuring Instrument for Ophthalmology" requires that the measurement error of the eye axis length AL be no greater than ±0.1mm. The measurement system error caused by the existing "time-gain compensation" technology, has become an important factor affecting the measurement accuracy

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