CN201248722Y

CN201248722Y - Supersonic bone mineral density detector

Info

Publication number: CN201248722Y
Application number: CNU2008201186120U
Authority: CN
Inventors: 王培勇
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-05-29
Filing date: 2008-05-29
Publication date: 2009-06-03
Anticipated expiration: 2018-05-29

Abstract

The utility model relates to a supersonic bone mineral density detector, which is characterized in that a main control circuit is composed of an FPGA/8051 USB/serial port and two IFOs, an ADC and a DAC and is respectively connected with a supersonic transmitting circuit and a receiving circuit. The receiving circuit is composed of an over-voltage protection circuit, a filter circuit and an amplifying circuit, an LT1568 chip of the filter circuit adopts a fourth-order Bessel low-pass filter, the amplifying circuit selects a two-channel ultra-low noise variable gain amplifier AD604 made in AD company and uses a vesicle-shaped supersonic probe and an intrinsic supersonic transmission medium, and the supersonic probe is controlled by a motor to move in six directions. The utility model provides two printing interfaces, namely a USB and a parallel interface, the test record can be stored, the on-line test and the remote data sharing can be provided in the situation that a microcomputer is connected, and because the detector adopts an integrated network card design, the grid transmission test data under the identical transformer, even different transformers, can be used.

Description

The ultrasonic bone density detector

Technical field

This utility model relates to electric class, particularly relate to a kind of hyperacoustic penetration capacity of utilizing, the characteristic that is directly proportional with ultrasonic propagation velocity according to bone strength, decay with the ultrasonic bandwidth that penetrates by measuring ultrasound wave conduction velocity in bone, thus the instrument or the system of mechanical strength, density, elasticity, micro structure and the fragility etc. of judgement bone.

Background technology

Skeleton is the main body frame that supports human body this " meticulous building ", and the size of its opposing foreign impacts ability is directly proportional with the height of bone density.In addition, skeleton is the place that stores calcium except that can protecting vitals to escape injury for muscle provides support simultaneously, and these calcium are that to keep the human body cell function necessary.Therefore, Jian Kang skeleton provides assurance for life security.Bone loss, the skeleton calcium deficiency causes bone density to lower, and causes osteoporosis when serious.Along with the prolongation of population average life and increasing of the aged, osteoporosis has become one of serious disease that influences health.The whole world has people more than 200,000,000 to suffer from degrees of osteoporotic disease approximately at present, and its sickness rate has leapt to commonly encountered diseases and frequently-occurring disease the 7th.Yet on clinical medicine, also do not repair the way of loose skeleton at present fully, can only keep by supplement calcium and vitamin D.In addition,, thereby can be ignored, so osteoporotic early diagnosis and prevention just seem particularly important by most of people because osteoporotic pathogenic process is very slow, and does not have special clinical manifestation.

Osteoporosis does not often have symptom, is subjected to little wound and fracture takes place just is caused attention up to bone.Osteoporosis is that a kind of osseous tissue microstructure is impaired, the continuous minimizing of bone ore deposit composition and bone matrix equal proportion, the generalized metabolic disorder disease that bone fragility increases and the risk of fractures degree raises.Carrying out the bone density inspection, is to grasp the also key of prevention of osteoporosis loss ahead of time.The height of bone density directly reflects the degree of skeleton calcium deficiency situation and bone loss.Therefore, adopt convenient and method results of regular determination bone density accurately, to understanding skeleton whether calcium deficiency and bone-loss situation, prevention of osteoporosis and observe its therapeutic effect promotes national physique health etc. all significant.In addition, in time carry out bone density and measure and not only can effectively prevent the generation of fracturing, but also can effectively reduce the spending of medical care expenses for country.

In clinical medicine, bone density is measured general single photon/two-photon absorption method, CT scan method, the monoenergetic/dual intensity x radiation absorption method of adopting, the employed instrumentation of these methods is loaded down with trivial details, volume is bigger, carry inconvenience, expensive price, and radioactive pollution etc. is arranged, the laboratory that therefore can only be fixed on preventer is used.Ultrasonic physical diagnosis Therapeutic Method as a kind of safety economy, (as ultrasoundcardiogram, ultrasonic therapeutic apparatus etc.) are widely used, but utilize the method for ultrasound wave principle mensuration bone density actually rare, utilize the ultrasound wave principle to measure the irradiation that bone density operator and detected personnel have avoided γ or x ray, and the height of bone density can directly reflect the degree of skeleton calcium deficiency situation and bone loss.

It is calcaneus that present ultrasonic bone density is measured modal position, why select this position to be because calcaneus 90% is made up of spongiosa, and the metabolism rate of spongy bone is 8 times of cortical bone, can be more early more accurate prediction osteoporosis and risk of fractures degree, and the calcaneus soft tissue is thinner, has bigger parallel surface to be easy to measure.When sound wave was propagated in medium, wave amplitude increased with distance and reduces, and Here it is ultrasonic attenuation is obeyed index law, and the mechanism of ultrasonic attenuation is complicated in the biological tissue, and main cause has absorption, scatter attenuation and the acoustic beam diffusion of medium to sound wave.

The utility model content

This utility model is divided into governor circuit, radiating circuit and receiving circuit on function.Its basic functional principle is under the integral body control of PC, by governor circuit to the radiating circuit output signal, radiating circuit output drive signal, drive ultrasound emission probe emission ultrasound wave, ultrasound wave arrives ultrasonic receiving transducer by bone to be measured, and acoustical signal is converted to the signal of telecommunication, after the filtering amplification, carry out the AD conversion again, the digital signal after the conversion enters PC by governor circuit and carries out digital processing, and the signal in the way uses oscillograph to monitor.

Radiating circuit: ultrasound wave is the vibration wave (more than the 20kHz) that a kind of frequency surpasses human auditory's upper limit, the ultrasonic frequency range that is suitable for most the bone characteristic is 0.1～1.0MHz, 0.2～0.6MHz particularly, hyperacoustic overall attenuation and its frequency are linear approximate relationship.Because the expansion of system, transmitted bandwidth need reach more than the 3M, and ultrasonic probe will produce ultrasound wave, need add the voltage about 80V thereon, so it promptly is the design high bandwidth that design can send the key problem of the ultrasound emission circuit of any wave mode, high-tension signal amplification circuit.At present general integrated operational amplifier circuit is difficult to directly reach these indexs, so adopt high performance amplifier and transistor, has been built into the high frequency amplifier part in the ultrasonic transmit circuit.The function that it is realized is exactly input signal to be carried out the amplification of amplitude and power, makes the signal that can not drive probe originally, is amplified to and can drives probe signal.

Receiving circuit: though the output signal of transmitting terminal up to more than the 70V, ultrasound wave is through the decay in the transmission course, the signal that receives can very faint (may have only several millivolts), must carry out filtering to the received signal and amplify.Therefore, the receiving circuit of native system is made up of overvoltage crowbar, filter circuit and amplifying circuit 3 parts.When input signal required owing to reasons such as interference exceed amplitude, overvoltage crowbar work was protected late-class circuit.Filter circuit adopts the LT1568 chip of LINEAR, and it is a have utmost point low noise, high frequency active RC filter assembly of elements, adopts 4 rank Bei Saier low pass filters, regulates resistance and can regulate bandwidth to the frequency that needs.Because two kinds of situations may appear in ultrasound wave in transmission course, a kind of is to have run into bone, and another kind is not run into bone.The signal amplitude that both of these case receives is different, and we will receive for the signal of these two kinds of different amplitudes, because in the date processing of back, contrast this two kinds of different signals.Therefore we need variable gain amplifier to finish, and select the dual pathways ultra-low noise variable gain amplifier AD604 of AD company for use, as long as variable gain amplifier is provided different voltage signals, can obtain different gains.

Governor circuit: governor circuit is the core of native system, mainly by FPGA/8051, the USB/ serial ports, FIFO, ADC, DAC forms, wherein the USB/ serial ports is used for the communication with exterior PC, since and have the difference of transmission speed between PC interface and AD, the DA, cushion the correct transmission of realization data with two FIFO.DAC is used to generate signal, selects the ADV7125 of AD company for use, can realize 8 precision, the conversion speed of 330M; ADC selects the AD9050 of AD company for use, has the conversion speed of 10 precision and 40M.By the signal that the receiving circuit probe receives, after filtering is amplified, send into AD9050, provide ENCODE signal by FPGA/8051 again, can realize being converted into digital signal by analogue signal.

This utility model is considered following problem in design, also be principal character of the present utility model: one, design special ultrasonic receiver, and select the ultrasonic echo in communication process of identification, the signal of non-sclerotin thickness is judged in conduct behind the filtering noise reduction; Two, select to use the ultrasonic probe of vesicle type, in accumulate the transonic medium, two-way test receives on the ultransonic basis in effective emission, and comparatively suitable skin sense is provided, and reduces detected person's immoderation; Three, ultrasonic probe is by Electric Machine Control, and the design of electrical motor that six directions are adjusted automatically, remembered has been guaranteed the concordance at detection position; Four, compatible multiple printer provides USB and LPT two kinds of printing interfaces, under the situation that unit uses, can store test record, also can report by printing test; Five, provide on-line testing, teledata to share under the situation of microcomputer connecting, test database has the calling of case, the correlated function of same testee's different time stage test result.Six, unique integrated network card design, can utilize with under the transformator not even with the electrical network transmitting test data under the transformator.

Description of drawings

The vesicle design of Fig. 1 ultrasonic probe and detection position sketch map

1 vesicle, 2 receiving transducers, 3 skins, 4 transmitting probes

Fig. 2 governor circuit structural representation

Fig. 3 radiating circuit structural representation

Fig. 4 receiving circuit structural representation

The specific embodiment

Further specify the working condition of ultrasonic bone density monitor below in conjunction with legend, as shown in Figure 1, a ultrasonic probe is respectively arranged in the heel both sides, one is used for emission, one is used for receiving, when the detected person was placed on the foot that exposes heel in the detector, ultrasonic probe can move on six direction, makes ultrasonic probe to be adjacent to by the side comparatively closely.Described this instrument obtains ultransonic amplitude fading value by the transmission signal that sees through calcaneus, further calculates BUA, goes out actual width of calcaneus with two-way supersonic sounding in addition and revises the BUA value.

Ultrasonic backscattering B parameter UB can provide BUA and SOS the information that can not provide, studies show that ultrasonic backscattering can be used as the index of bone structure state, the osseous tissue acoustic impedance characteristic of backscattering reflection has been represented the bone changes of microstructure, and can provide and the relative relevant sclere information of risk of bone fracture rate.Particularly, what cause backscattering to reduce with the variation of form (attenuate, thinning even fracture) to be accompanied by bone trabecula quantity in the calcaneus in the organism aging process process.

Measure the pulse echo scattering waveform of calcaneus backscattering,, the bone trabecula echo that takes out is done the scattered power analysis of spectrum, can obtain bone trabecular backscattering coefficient spectrum σ by adding time window with skin and the filtering of cortical bone echo _b(dB) and integral mean backscatter intensity BUB, these two parameters all are subjected to the influence of interior bone girder microstructure, bone trabecula more even thickness, full, connect that closely then the BUB value is big more.

Instrument of the present utility model itself has from memory function, by the multiple printer of usb compatible, can report that detection time is shorter by the unit printing test, only needs about 10 seconds.

Claims

1. a ultrasonic bone density detector is characterized in that by FPGA/8051, the USB/ serial ports, and two FIFO, ADC, DAC forms governor circuit, connects ultrasound emission circuit and receiving circuit respectively.

2. according to the described ultrasonic bone density detector of claim 1; it is characterized in that receiving circuit is made up of overvoltage crowbar, filter circuit and amplifying circuit 3 parts; the LT1568 chip of filter circuit; adopt 4 rank Bei Saier low pass filters, amplifying circuit is selected the custom-designed ultrasonic receiver of dual pathways ultra-low noise variable gain amplifier AD604 of AD company for use.

3. according to the described ultrasonic bone density detector of claim 1, it is characterized in that selecting to use the ultrasonic probe of vesicle type, in accumulate the transonic medium.

4. according to the described ultrasonic bone density detector of claim 1, it is characterized in that on six direction, moving by the Electric Machine Control ultrasonic probe.

5. according to the described ultrasonic bone density detector of claim 1, it is characterized in that providing USB and LPT two kinds of printing interfaces, under the situation that unit uses, can store test record, also can report by printing test, integrated network card design, can utilize with under the transformator not even with the electrical network transmitting test data under the transformator.