CN101444422A - Electrical impedance device and method - Google Patents

Abstract

The present invention relates to an electrical impedance device and method, wherein a method forscreening whether a patient has abnormal structure or not at a position using an electrical impedance (EI) includes the steps of: a) obtaining patient EI measuring data; b) generating image data based on the measuring data; and c) estimating the image data, such that a first determination of the exist of the abnormal structure is made.

Description

Electrical impedance device and method

Technical field

The present invention relates to electrical impedance (EI) examination, for example, for human health screening.

Background technology

Mammography is the current standard imaging form for detection of breast carcinoma.Carrying radiation dose through in breast, mammography program is uncomfortable and/or pain for a lot of women conventionally.In order to obtain suitable radioscopic image, its process generally includes breast is close on screen board.Equally, the relatively high Financial cost of mammography equipment also makes it in a lot of developing countries, can not be widely adopted.In addition, be exposed in X ray ionizing radiation and can finally damage breast tissue, particularly pass through accumulative effect.Mammography has relatively high mistaken diagnosis and the percentage ratio of wrong detection in addition, and this can cause not detecting tumor or unnecessary biopsy, surgical operation, chemotherapy and/or radiotherapy.

Recently, electrical impedance x-ray laminaghaphy (EIT) detects breast pathological symptom at noinvasive and comprises aspect breast carcinoma and being developed.EIT program is applicable to the age used, and patient uses comfortable, and anatomy and two kinds of information of physiology are provided.The fund input of EIT equipment is far below X-ray equipment, makes it can be supported and accept in a lot of countries.EIT program does not have any safety hazards for patient and clinician, and its result has definitiveness aspect symptom before detecting the early symptom of cancer, early stage little tumor and cancer.

Conventionally, the technology after EIT comprises the electrod-array that is positioned over target site, and a single electrode away from its placement, and this single electrode is generally positioned over patient's wrist.Electrode in array adopts default electric frequency order to drive, and measures the electric current that flows through each electrode causing thus simultaneously.Can obtain like this electrical conductivity contour map of target area.

The result images obtaining from EIT system shows as high conductance region to show as relative low conductivity region ，Er Dui compare sclerous tissues as organs such as lungs.EIT system is compared with normal structure and in electrical conductivity, is shown difference cancerous issue, thereby provides a contrast the resulting conductivity map of the signal by receiving from electrod-array.Like this, cancer symptoms can be measured from conductivity map.This method is for having special effect with the significant malignant tumor of normal surrounding tissue nature difference in breast.

The shortcoming of early stage EIT system is the low resolution of image, and part is because resolution significantly reduces along with entering the increase of the degree of depth in patient body, and image can only obtain from the electric conductivity difference value between adjacent electrode measurement.Therefore, for the 3-D image in reconstructed object region, above-mentioned 2 dimension (2-D) EIT electrod-arrays are often supplemented recently, and soon reconstruction software is applied to 2-D array data and obtains result.This comprises a kind of algorithm for reconstructing, and the form that obtains data that it is main is target area is parallel to electrod-array in patient body multiple profile on different depth.Although known that this program can provide the image resolution ratio of enhancing in some cases, but also require further improvement image resolution ratio and/or cancer early symptom or entity tumor, detect electric frequencies that these use due to EIT system and be not easy to be resolved out in image.

A known 3-D EIT system is disclosed in the publication Physiologicalmeasurements 22 (2001) 9218 that Britain physical society publishes and distributes, a system has been discussed and in conjunction with one, has been positioned over structural electrod-array to be measured, two supplemantary electrodes are placed away from electrod-array, an interchange (AC) current source, for measuring a device for electric potential difference, and manifest for rebuilding the accountant that distribution of conductivity is one group of tomographic analytic image.This journal of writings has been discussed the comparative analysis of the electrical impedance images of the breast that adopts the normal and canceration that disclosed system obtains.The 0.2mA current drives of system proportion 10kHz.To a given input electrode, an output multi-channel multiplexer is sequentially by the every other electrode in array, and electric potential difference detects and measures simultaneously.Input electrode conversion, and output multi-channel multiplexer sequence repeats.Thereby conversion each time discussed in this article, single lead-in wire reduces the spuious coupling (spuriouscouplings) of crosstalking and producing in multiplexer, simultaneously can simplification device and reduce costs.Described electric current injection and tension measuring circuit and the identical inventor (people 1995 such as Cherepenin, electric current injection and the tension measuring circuit of the electrical impedance x-ray laminagraphy for the quiescent imaging people such as Korjenevsky 1997) are similar, the four measuring cycle of 65280 voltage measurements (256 electrode * 255 sequence) is used to again by reconstruction software, obtain image, has only utilized single measuring frequency.

Having realized that the accurate detection of picture quality/resolution and/or cancer or tumor early symptom, or cancer or the non-existent more definite mensuration of entity tumor early symptom, can beyond said system, reach.

For the above reasons, an object of a kind of form of the present invention is just to provide the improved electrical impedance x-ray laminaghaphy of the image resolution ratio with increase, or the probability that detects definitely cancer early symptom or there is no the enhancement of cancer is provided.

At electrical impedance x-ray laminaghaphy, make electrical properties (real part of impedance or admittance and/or the imaginary part of main body biological tissue, the absolute value of impedance, the phase place of impedance or admittance, electric capacity or electrical conductivity, when specific distribution or some functions of impedance or admittance component) can manifest, the localized variation of electrical conductivity makes to detect tumor, inflammation and/or cyst etc.Yet, in order to obtain proper data, quite most, if not all, for applied current with measure the electrode that obtains signal and must reliably contact the surface in subject goal region.Electrical impedance x-ray laminaghaphy for imaging and diagnosis is used the plane electrode array that is attached at crust at present.Must the electrod-array on crust be applied to target area by enough power, for example breast, to be close to target area, thereby makes enough electrode contacts.Although this may make the very uncomfortable or pain of main body, large, the soft region of main body for example large breast can reach reasonable contact.Yet, if target area is little, low pliability curve, for example little breast, for example typical Southeast Asia or less women of age, or the women who enlarges the bosom, obtain measurement reliably or any important measurement and for technical staff, become difficult, while main body is very uncomfortable or pain also.In addition, any data of acquisition can lack effectiveness due to a large amount of bad or noncontacting electrodes.

In experiment structure in the past, have positioning of electrode on motor-driven support.Then comply with for example shape adjustment of breast of target area.Yet, this mode be not suitable for wherein 256 measurement electrode need optimal placement with in the 3-D measuring system contacting with breast (IEEE transactions on medical imaging, Col.21, No.6, in June, 2002, PP638-245).

A known devices is to describe in 6308097 at U.S. Patent number.This device is used multi-frequency measurement to obtain the space distribution information of inside of human body electrical properties.The electrical conductivity 2-D that device is used an electrod-array to realize body surface draws.By the current value of each electrode, directly define the brightness of respective image pixel.This electric current depends on the impedance of human body on current path.The depth resolution that enters human body can not realize, because sensitivity reduces rapidly with the degree of depth.Use this system, only have 2D imaging likely, and picture quality is strictly limited by current flowing physical property.The data set of collecting is few, and therefore further date processing can not be implemented.Use this device, a voltage source is connected with all electrodes simultaneously, measured by the electric current of each electrode.Therefore same electrode is not only for applying voltage but also for measuring electric current, this makes system very responsive for skin electrode contact situation.Humidity, cutaneous scarification, nevus etc. can obviously change result images.In addition, the data set that device is collected thus comprises N value, and wherein N is electrodeplate.By simply data 2D being drawn on PC screen, lacking of information limited possible date processing.

For the above reasons, require further improvement patient's scan protocol and technology.

For example, methodological providing, thus improve scanning technique and improved judgement, and/or electrical impedance x-ray laminaghaphy, the shape that it provides improved imaging and/or adapts to target area.

Summary of the invention

Consider foregoing, one aspect of the present invention provides a kind of method of body region electrical impedance examination of main body, comprises the following steps, and locates at least one multicomponent and pops one's head at least one respective surfaces of body region;

On the application element that at least electric current under two kinds of different frequencies is popped one's head in to multicomponent;

The signal being obtained by different frequency on detecting element; With

Based on detection signal, generate at least one width impedance diagram.

Multi-frequency electrical impedance imaging is measured in order to improve view data, advantageously makes image result strengthen.

Electric current can first be applied on the element of multicomponent probe under first frequency, is transformed into subsequently on the element that is applied to multicomponent probe under second frequency.Therefore, depend on that the data of the electrical impedance figure of first frequency can be determined and for searching the undesired tissue regions under this frequency, the then impedance diagram data comparison relevant to second frequency.Like this, can identify the different signal of telecommunication frequency dependence of performance or the dissimilar tissue of irrelevance.For example, benign cyst and malignant tumor can show different characteristics under given frequency, and therefore can more respectively they are identified by impedance diagram data.

Preferably, under first frequency, measure, then applied signal is switched to another frequency, preferably by software program interface, to implement follow-up measurement under second frequency.The frequency of estimating 10kHz and 50kHz can be preferably; Yet a plurality of frequencies arbitrarily that are enough between 1kHz and 1MHz distinguish all can estimate, although due to the β of health soft tissue electrical impedance distribute (beta-dispersion) preferably 10kHz to the scope of 100kHz.

According to preferred form of the present invention, multi-frequency can be applied on the element of multicomponent probe simultaneously.

Therefore, can first apply first in multi-frequency, and then apply other (frequency occurring in sequence), or application (simultaneous frequency) simultaneously.

Although two minimum frequencies provide improved result, the present invention should not be regarded as being limited to only have two frequencies.For example, the multi-frequency of any number can be employed, and two different frequencies are minimum, and the frequency of greater number (as long as they are fully separated in frequency spectrum) can be employed.Use can provide the resolution of enhancing more than the multi-frequency of two, and therefore impedance diagram result and the diagnosis perceived of enhancing are provided.

Another aspect of the present invention provides the instrument to main body region electrical impedance imaging, comprising: multicomponent probe, comprises a plurality of sensing elements and be adapted to be mounted to first side in region; The second probe, comprises that at least one is installed on the element of main body away from the first multicomponent probe; Electric signaling device, for being applied to the electric current under at least two different frequencies the element of multicomponent probe; And the data that obtain for the electric current from applying under the electric frequency of difference obtain the device of electrical impedance images figure.

Multicomponent probe can comprise 256 electrodes.

An optional form of the present invention, for electrical impedance x-ray laminaghaphy provides multicomponent probe apparatus, comprising: flexible material and a plurality of electrode that is arranged in material surface.

Like this, the electrod-array of the multicomponent of comfortable probe is provided out, thereby its given shape that can make the shape of array adapt to subject goal region allows the electrode of contact greater number, the i.e. array of a comfortable.What increase has the electrode number of good contact with surface, target area, the reconstruction image (impedance image figure) of better quality can be provided, thereby the diagnostic value that obtains data is provided.

Preferably, flexible material provides takes film electroded waterproof or water resistant, thereby prevents or at least reduce the infiltration of wetting agent in measuring process.For example, film can comprise or be manufactured by fabric coat with rubber or polymerization or plastic sheeting.

Flexible material can be supported by basic material, and as fiber or porous material, it can be so that electrode extruding, to surface, target area, allows flexible material to comply with the shape in subject goal region simultaneously.

The penetrable flexible material of electrode and/or some electrodes can be arranged in the outer surface of flexible material at least partly.Similarly, coverlay, as waterproof/film of water resistant can comprise through hole, at least in electrode is through through hole.

Can cover under a kind of conductive material by projected electrode array, this material preferably has the electrical conductivity matching with target area surface conductivity, as mated for example electrical conductivity of skin of biological tissue.Like this, electrode can be attached at for example inner surface of film of cladding material, thereby holding device outer surface is clean and harmless.

A significant advantage of multi-frequency electrical impedance technology is particularly useful in mammography, benefit is more than known single-frequency technology, it is diagnosable breast disease not only, can also help Accurate Measurement cyst form under condition that the equal value index number of any stage electrical conductivity at the menstrual cycle of corresponding age group not there are differences.According to morphology, follow dysplastic hypertrophy and special-shaped incidence rate higher than thering is cyst form, can make a definite diagnosis high-risk colony like this, thereby carry out special medical nursing to prevent breast cancer development.

One or more forms of the present invention realize the so-called inverse problem of separating Maxwell equation under quasistatic approximation.In the reconstruction that the method distributes at 3D and picture quality, there is no theoretical restriction, but suitably need the accuracy of sufficient calculate and measurement.The complexity of the number of electrode, the accuracy of measurement, algorithm for reconstructing is common limiting factor.The data set of collecting is enough for the solid of given electrod-array.Embodiment can rebuild 3D Static Electro conductance from inside of human body.A large data set can be collected and then be redeveloped into parallel faultage image plane.When the present invention can work as voltage readings and do not carry out, realize four-probe measurement on the electrode of injection current.Such measurement changes with the contact situation on skin surface hardly.The software utilizing in various embodiments of the present invention can provide very fast " in advance " imaging without resolution in the degree of depth, is mainly used in drawing the abnormal electrode figure of contact.

One or more embodiment of the present invention can obtain a collection data set that comprises the individual value of N (N-1).Injecting electrode to each generation current, measurement can order be carried out on N-1 electrode of residue.This cycle can repeat N time, and for example, each electrode is all as injecting electrode thus.Result data collection can comprise possible maximum information, and from then on can act on the solution of 3D inverse problem.A backprojection algorithm quick and that strengthen can be used for rebuilding some the faultage image planes through breast tissue.3D tomographic image reconstructing from same data set can generate detail pictures, and illustrating compares with normal structure exists or the tissue that do not have problems.

Another aspect of the present invention provides a kind of examination patient method, comprises the following steps:

A) obtain patient's electrical impedance (EI) measurement data;

B) measurement data is applied to a kind of algorithm, thereby produce view data;

C) evaluate image data, thereby make, problem tissue exists or non-existent mensuration for the first time.

Preferably, the depth data value that measurement data can be used as from a plurality of datum planes through tissue obtains.For example, measured value can be used as that for example many (level) planes of breast tissue or the depth data value in " lamella " obtain through tissue of patient.

Initial assessment can provide suggestion for the first time, and whether clearly mensuration problem organizes appearance.If what does not all detect, patient can for example assess after 12 months in a following period so.If detect definite extremely, will require patient to carry out further, more detailed examination.Therefore Yes/No examination rules are provided.This initial assessment can be operated by for example remote districts of low qualification or the people of poverty-stricken area, there carry out details and expensive assessment very difficult, there is no cost efficiency or cannot use.In the situation that little extremely being arrived by initial detecting will require patient further to assess, or require in given period as 6 months further initial assessments of laggard row.View data and/or measurement data can remote storage and/or (further) long-range assessments.

Method can preferably include measures the pernicious probability P occurring in scanning tissue.Can comprise utilize equation P=1/ (1+exp (and a), wherein, preferably,

a＝b ₀+b ₁x ₁+b ₂x ₂+b ₃x ₃+b ₄x ₄+b ₅x ₅

X ₁for patient age,

X ₂for the average of original measurement value,

X ₃for the intermediate value of original measurement value,

X ₄for the average of view data,

X ₅for the standard deviation of view data,

Here provided a value between 0 and 1,0 indication do not exist pernicious and 1 indication exist pernicious.Therefore, 0 value can cause patient not need suggestion further to assess, and 1 needs patient to be reevaluated.Fall into value between 0 and 1 and can be used for measuring patient whether healthy (clear), whether need further to assess or return in given short-term framework and carry out another scanning.

Another aspect of the present invention provides a kind of method of utilizing electrical impedance examination patient whether to have abnormal structure, comprises the following steps:

A) connection electrode array is to patient, and one in electrode as receptor, and each in a plurality of residue electrode is as emitter;

B) by each transmitter electrode, to patient, import a current signal into;

C) at receptor electrode, receive described current signal;

D) change a transmitter electrode into receptor electrode, and conversion receiver electrode is a transmitter electrode;

E) for each emitter and receptor electrode repeating step b) to d);

F) by a plurality of signal image data generatings that receive;

G) utilizing view data to assess undesired tissue exists or does not exist.

Term " conversion " refers to functionally (electricity Shangdi) conversion related electrode.View data can be used for from wherein building several depth layer images.Several degree of depth " figure " of organizing each layer are shown and provide the observability of enhancing for tissue below, thereby and allow the comparison between adjacent layer to help assessment more accurately whether to have undesired tissue to exist.

Initial assessment provides the assessment of the positive-feminine gender, if positive or be even evaluated as critical, assess and can be used for obtaining more definite measurement result for the second time or further, this measurement result is about any undesired presence/absence and preferred scope and toxicity organized.

Preferably, method can comprise by measurement data and generate a plurality of depth image layers, and each image layer is to go deep into the continuous depth image of human body.Make like this plurality of EI images of patient, lamella for example, can be according to assessment each other, and for example, whether tumor appears in 3D, and if so, tumor diffuses into patient's scope so, and the type of tumor can be measured by 3D shape observability.

It is the device of patient's electrical impedance examination that another aspect of the present invention provides a kind of, comprises that output has a plurality of signals of telecommunication of different frequency to patient's device; At least one input, receives the electrical impedance signal being produced by input electrical signal from patient; And blood processor, by the electrical impedance signal receiving, generate pictorial data.

Device is connected in an element arrays removedly, and wherein each arrangements of elements is at least one signal of telecommunication of conduction is to patient.Blood processor can comprise that the signal based on receiving generates the device of patient's multilamellar (lamella) view data.

Accompanying drawing explanation

Fig. 1 illustrate according to an embodiment of the invention one in accordance with the cross section of electrode array device.

Fig. 2 illustrates and is applied to supramammary one embodiment of the present of invention.

Fig. 3 illustrates an optional embodiment of the present invention, has external conductive film and internal electrode.

Fig. 4 is the flow chart of evaluation scheme according to an embodiment of the invention.

Specific embodiment

At least one embodiment of device in the present invention and associated method of use will be described hereinafter.Yet this does not mean that the generality of restriction invention, and mentioned any prior art in this description, and though be this part or other parts, all do not mean that and admit that this technology or other prior aries belong to common practise.

The apparatus and method of at least one embodiment of the present invention have been utilized 256 electrod-arrays to each breast scanning.An input that is connected to voltammeter (receptor) by multiplexer (conversion) in electrode.Remaining 255 electrodes are connected respectively to a current source successively by another multiplexer.Receptor is each emission electrode measuring voltage (measuring for 255 times) at the electrode of pre-selected.Receptor is connected to the next electrode of array, and again repeats said process.Therefore, there is the modification that 256 kinds of receptors connect, and every kind of such connection has the modification that 255 kinds of emitters connect.In a data acquisition, altogether 256*255=65280 independent data value will be obtained.The maximum possible data collection that these 256 electrod-arrays that are use provides can be collected.

This large amount of data set makes 3D inverse problem be solved for predetermined potential equation, and in noninvasive mode, rebuilds patient body internal electrical conductance 3D distribution thus.This imaging, except apparatus and method of the present invention, all can not realize, and reason is the reconstruction platform that lacks measurement data and there is no date processing.

Utilize the one or more embodiment of the present invention, can obtain the visual depth data of whole breast substantially.By the data set obtaining, being carried out the electrod-array radius that the depth capacity of 3D reconstruction determined by electric field geometry is limited.Therefore,, in order to obtain rational imaging depth, the size of array can optimize to adapt to breast size.That is, 256 electrod-arrays cover whole breast surface substantially.

Embodiments of the invention utilize filtering (filtered), weighting (weighted), along electric field equipotential surface back projection (back-projection), separate inverse problem, that is, by electrometric result of carrying out from its surface, be calculated to be the spatial distribution of the medium of picture.

Therefore, in the region that embodiments of the invention can cover at array (space drawing), realize the electrical conductivity of any spatial point (voxel) or the reconstruction of resistance value, for example, " hemisphere " being formed by the breast being placed in after array, the radius of this breast is identical with electrod-array radius.For this 3D information is presented on display, as computer screen, the present invention can provide cross section 2D image sequence or the collection that presents the inner different depth layer of breast tissue (depth data).These layer can take several millimeters as interval, for example, 5-10mm interval has been found to be effectively, preferably 7mm between left and right every.Patient's surface skin and the region below adjacent surface present maximum electrical impedance, therefore affect significantly measurement result, and can not provide any useful information to the situation of breast tissue itself.Apparatus and method of the prior art lack depth data and cause skin properties to manifest in the pictorial data obtaining, and occur image deflects and pseudomorphism, rather than breast tissue below.The present invention can, by increase a plurality of cross sections of pictorial data or the form of " lamella " obtaining with the breast tissue degree of depth, utilize the true 3D of breast tissue character to distribute.

(the inverse of impedance, 1/Z) is associated with the physiological status of the tissue being imaged to have found electrical impedance (Z) or electrical conductivity.For example, have been found that cancerous issue can illustrate 2-20 doubly to the electrical conductivity of normal structure of the same race.Therefore, obtain body internal conductance rate distributed data favourable and effective (and importantly noninvasive) method diagnosis various diseases is provided.

Utilize the present invention, can in being imaged tissue, realize the electrical conductivity of any selected spatial point (voxel) or the reconstruction of impedance correlation, for example, in radius and the essentially identical breast hemisphere of electrod-array radius.For this 3D information is presented on display, have been found that it is favourable using the one group of cross section 2D image obtaining from the different tissues degree of depth.Therefore can not only at horizontal plane but also in the degree of depth, estimate the scope of any undesired tissue (tumor, cyst etc.).The image ratio of varying cross-section allows to pseudomorphism and mistake to distinguish from real goal.

Have realized that, practitioner and other people, particularly low-level personnel or remote districts or the operator in " battlefield ", carry out examination inspection and need a screening instruments, at least can make initial assessment, image result and those view data results about normal structure that needs are further noted are separated.

The present invention of one or more forms can provide a kind of algorithm, and this algorithm allows to estimate by the measurement result collection providing the probability that disease or " improper " tissue occur.Algorithm can be combined with training data utilization, and/or result can be by comparing and confirm with optional inspection.

One group of statistics parameter is calculated by measurement result and reconstructed image data.These values are used the linear combination of one group of coefficient, and these coefficients are in advance by being used training data and/or least squares approach to obtain.The linear junction obtaining share the formula in logistic, makes all values in 0-1 (that is, probability) interval.

The image and the view data that obtain can be used for information measurement occurrence thus, the peak electricity conductance in the average conductivity in area-of-interest, burnt territory for example, etc.

The result being obtained by the pictorial data obtaining allows to obtain at least one initial assessment of (breast) tissue, and for example good-bad (OK-not OK), or healthy-unhealthy (clear-not clear), relate to further assessment.

Result can form in writing form, comprises image, if necessary, and the suggestion to further assessment, if any.

The outward appearance that 3D imaging technique of the present invention and device make user be a plurality of cross-section according to the range data image strengthening is separated pseudomorphism and real target area.Another instrument that filters pseudomorphism is on figure, to find bad electrically contacting.Any bad electrically contact near visible target all can regard as possible pseudomorphism, and measure and can repeat.

One or more forms of the present invention relate to uses multi-frequency electrical impedance x-ray laminaghaphy to diagnose dyshormonal cystic hyperplasia of breast.

Have realized that every year and register in Russia more than approximately 34,000 new breast carcinoma cases, and the statistical value that is accompanied by patient age is increasingly young.30 years old following women of 25% and 60% 40 years old above women are diagnosed as dyshormonal breast (breast disease) case.Although breast disease is not identified as a kind of deterministic cancer omen, but breast carcinoma incidence rate in the patient who suffers from dispersivity dyshormonia Non-cancerous situation is 3-5 times, and incidence rate is 30-40 times in the breast disease patient who suffers from the warty form being worsened by galactophore epithelial cell hypertrophy.This evidence has improved the common concern degree to non-malignant growth, has opened the road that reduces incidence of breast cancer by mastotic effective treatment.Existing breast disease diagnostic method exists and has objective and limited applicability subjective quality concurrently.166 women (92 do not have breast condition of illness, and 74 have breast disease) are carried out to Integrated Checkout and adopted four kinds of methods: multi-frequency electrical impedance x-ray laminagraphy, ultrasonic examination, mammography and aspiration biopsy subsequently.The analysis that obtains data is that the vision based on electrical impedance images is estimated, the histogrammic estimation of the exponential sum of breast distribution of conductivity under multi-frequency inspection, according to Student standard (criterion), compared not measurement on the same group, and compared with ultrasonic and X ray data.Herein disclosed is the various forms of mastotic standards of multi-frequency electrical impedance x-ray laminaghaphy diagnosis of using.

I. foreword

For the above reasons, one or more forms of the present invention provide multi-frequency electrical impedance x-ray laminaghaphy to diagnose the illness, for example dyshormonal cystic hyperplasia of breast and breast carcinoma.

II. main body

Shown the main result test data that 166 women (in first group, 92 do not have breast condition of illness, and 74 have breast disease in second group) is carried out to Integrated Checkout below.In every group, according to breast tissue change of age grade, be divided into group:

Below 35 years old---there is the general stability state of breast tissue;

35-40 year---there is the forfeiture gradually of gland structure;

41-45 year---having significant conduit cylindrical epithelium (duct cylindrical epithelium) thickens, and basement membrane (basal membrane) thickens and sexually revises with connective fiber;

46-50 year---have by fibrous tissue around lactiferous ducts expansion and accidental cyst expand;

More than 50 years old---there is the slow closure of lactiferous ducts and little blood vessel, be accompanied by fatty tissue and form.

III. method

Application diagnostic method below:

The ultrasonic examination of breast tissue is all patients that are applied to for 5-9 days of its menstrual cycle; The instrument using is Ultrasonic C ombison530 ^tM, there is the linear 7.5MHz probe of electronics;

More than 35 years old women is in the mammography of carrying out for 5-9 days of its menstrual cycle; Use ' Mammodiagnost DCX ray instrument and at Kodak ^tMaCF A mammoray HDR film in min-R box;

Trial body is all carried out multi-frequency electrical impedance x-ray laminagraphy; The instrument using is an anti-x-ray tomography apparatus of 256 electrode resistance, by Russian Academy Of Sciences radio engineering and institute of electronics (Institute of Radio-Engineeringand Electronics of the Russian Academy of Science) research and development; The frequency of using is for 10kHz is to 50kHz; The time of selecting is 3-10 and the 17-28 days of menstrual cycle;

After ultrasonic and X-ray examination, aspiration biopsy is to realize with puncture needle by standardization program.

All check results are carried out to statistical procedures by selectable the whole bag of tricks, to obtain average and standard deviation.For checking data reliability, we take Student standard (criterion) and corresponding form.In addition so-called " method of least square ", (LSM or Gauss method) used by MATLAB 7.0 application softwaries.

IV. result

All dyshormonia hypertrophy processes in mammary gland are all called as term " breast disease ".Breast disease is defined as the disease of fibrous or cyst, and the breast with the wide range of proliferative or degenerative changes, and is accompanied by the epithelial cell (epitelic) and the undesired rate that is connected component that are mixed into various combinations.

In order to find out the potentiality of multi-frequency electrical impedance x-ray laminaghaphy in the diagnosis of dyshormonal cystic hyperplasia of breast, identify and carry out after the ordinary procedure of ultrasonic examination and mammography (more than 35 years old women).

92 women with ultrasonic experiments data form first clinical group [2]:

Ultrasonic type and their age of breast consistent (teen-age, reproduction period, premenopausal);

Ultrasonic imaging corresponding with their physiological periods (first or second stage of menstrual cycle);

The significant difference of breast tissue;

Parenchyma (parenchyma) thickness is no more than 14mm;

There is not the total symptom of focus (focal symptomatology), ductal ectasia, tube wall fibrosis;

There is not the variation in region, lymph effluent position.

Second clinical group comprises 74 women, discloses following ultrasound information [2]:

The ultrasonic type of breast tissue and their age are inconsistent;

In various diffusivity breast disease, glandular tissue layer thickness is greater than 14mm;

Tube wall fibroid changes;

The echo variable density of glandular tissue index is not typical for patient age;

Ductal ectasia, wall thickening, inner chamber increases,

Pipeline is irregular, along supervisor's expansion;

There are a plurality of cysts.

Breast disease women in group 2 is further divided into 2 groups according to breast disease type:

First kind breast disease group---there is no cyst component (41 patients);

Equations of The Second Kind breast disease group---there is one or several cyst (33 patients).

35 years old above women accept x-ray inspection and confirm diagnosis.Breast disease patient accepts anticancer and anti-special-shaped puncture fine-needle aspiration biopsy.

The analysis of multi-frequency electrical impedance x-ray laminagraphy starts from the consideration of electrical conductivity index, in standard element, provides.

The electrical conductivity index of the vertical or horizontal position of health and left or right breast does not have effective difference in statistics.Average index from the second scanning stage is used.The result obtaining is shown in table 1 and 2.

Interpretation of result record is as follows:

Electrical conductivity index grew proportionately with patient's age, and irrelevant with their grouping and menstruation stage;

According to the statistic obtaining, have realized that, under 50kHz and 10kHz frequency, women's (until 50 years old) that the breast disease of two types can make the age group of menstruation in two stage electrical conductivity of menstrual cycle lower than normal value (p<0.05 in all cases).

For postmenopausal women (age 51-55 year), breast disease does not affect electrical conductivity or only slightly surpasses normal value (difference is the upper inadequate p>0.05 of statistics).

In Equations of The Second Kind breast disease group, under 50kHz frequency, all in menstruation stage and postclimacteric electrical conductivity all higher than first kind breast disease;

In normal and Equations of The Second Kind breast disease, we can find out, under 10kHz frequency, no matter after menstrual cycle stage or menopause, there is obvious, statistically valid reduction (p<0.05 in all cases) in electrical conductivity in corresponding age group.

In first kind breast disease group, electrical conductivity index is all identical in all frequencies and all groups.

The anti-image result of comparison resistance following (Fig. 1):

The improper structure of image is caused by variation proportional to breast tissue, and this causes the inconsistent of electrical impedance type (teen-age, reproduction period, postclimacteric) and age;

The fibroid that the increase in Low ESR (hypo-impendance) region comes from fatty tissue changes, fibrosis tube wall and Kuper ligament;

Appear at the high impedance inclusion with clear profile in Equations of The Second Kind breast disease mammogram corresponding to the obvious expansion of cyst of breast or conduit.

The variation of the cross-sectional image of udder texture, by ultrasonographic results verification.

V. conclusion

By research, draw following conclusion:

Breast tissue electrical conductivity depends on women's age, and exists or do not exist irrelevant with the structural change of gland tissue.Abnormal or unusual for fear of what follow electrical conductivity age-dependent to produce, adopt " method of least square " (LSM or Gauss method) to process.Seeking this relevant parameter is measured.Same three rank multinomials statements for all clinical group of regression line under 50kHz

(f(x)＝p1.x ³+p2.x ²+p3.x+p4)，

And this polynomial coefficient (p1, p2, p3, p4) is tried to achieve by linear equation group system.

Normal:

50kHz(p1＝0.0025，p2＝-0.01893，p3＝0.06857，p4＝0.38)；

10kHz(p1＝0.005，p2＝-0.04357，p3＝0.1414，p4＝0.272)。

Breast disease 1 class:

50kHz(p1＝0.009167，p2＝-0.06464，p3＝0.1662，p4＝0.184)；

10kHz(p1＝0.0075，p2＝-0.05179，p3＝0.1407，p4＝0.188)。

Breast disease 2 classes:

50kHz(p1＝0.01167，p2＝-0.095，p3＝0.2733，p4＝0.136)；

10kHz(p1＝0.01167，p2＝-0.1007，p3＝0.2876，p4＝0.088)。

Although normally identical with the rule of conductivity variations in age abnormal development process, electrical impedance x-ray laminagraphy method of the present invention has guaranteed that by the decline of the women's of the corresponding age group in menstruation stage under different frequency electrical conductivity index reliable breast disease diagnoses.Electrical conductivity normal and mastotic postmenopausal women does not have difference, has confirmed that abnormal development is that dysfunction by hormone system " ovary-breast " causes, rather than a kind of independently disease.

Multi-frequency electrical impedance x-ray laminaghaphy is compared unifrequent major advantage and is, it is not only can Diagnosis of Breast sick, and can, in the situation that the average conductivity index of all corresponding age group of menstrual cycle stage not there are differences, help to measure cyst form.According to morphology, be accompanied by dysplastic hypertrophy and special-shaped incidence rate higher than following cyst form, this makes to find high-risk cohort to carry out special medical nursing, thereby prevents the development of breast carcinoma.

Visible change in mastotic faultage image be confirmed to be that quantitative performance by electrical conductivity carries out, can get rid of any false diagnosis like this.

The safety of electrical impedance x-ray laminaghaphy makes it can comprise as any age young woman's breast examination inspection method.

Table 1: illustrate age groups in the menstrual cycle first stage with postclimacteric women, the electrical conductivity Mean value of index (10kHz, 50kHz) of the breast tissue in normal and breast disease symptom.Numerical value provides together with deviation:

Table 1

Table 2: illustrate age groups in menstrual cycle second stage with postclimacteric women, the result (10kHz, 50kHz) of the electrical conductivity Mean value of index of the breast tissue in normal and breast disease symptom.Numerical value provides together with deviation:

Table 2

One or more forms of the present invention provide or in conjunction with a kind of 3D EIT mammogram analytical method:

1. the bad contact and diagonal angle (diagonal) element (that is, when transmitter electrode is consistent with receptor) that comprise turning can remove from original measurement result.If all contacts are all good, the 256*255=65280 of a 256 electrod-arrays value can obtain.Average and intermediate value will be calculated the value from obtaining.

2. image reconstruction data (for example 7 transverse section, each has 36 * 36 pixels) can be combined into an independent array.Average and standard deviation value can be calculated by these data.The latter uses following formula to calculate:

$s={\left(\frac{1}{n-1}\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{(y_i-\stackrel{\&OverBar;}{y})}^2\right)}^{1/2}$

Wherein s is standard deviation, and n is the sum of value (pixel), y _ithe value in array,

it is the average of array.

3. pernicious probability P can be according to Equation for Calculating below:

P＝1/(1+exp(-a)，

Wherein

a＝b ₀+b ₁x ₁+b ₂x ₂+b ₃x ₃+b ₄x ₄+b ₅x ₅’

X ₁patient age (get arithmetic point after three),

X ₂the average of the original measurement value that obtains according to paragraph 1,

X ₃the intermediate value of the original measurement value that obtains according to paragraph 1,

X ₄the average of the image that obtains according to paragraph 2,

X ₅the standard deviation of the image that obtains according to paragraph 2,

Coefficient b _kby bringing training dataset into method of least square, calculate.Be the example by the coefficient of limited training dataset acquisition below, and provide sensitivity and the specificity higher than 75% to each.

b ₀＝-10.6011

b ₁＝0.213103

b ₂＝-0.0056579

b ₃＝0.0055994

b ₄＝10.5179

b ₅＝-12.2619

Further form of the present invention is described with reference to accompanying drawing.Fig. 1 illustrates the cross section of a device according to an embodiment of the invention, and electrod-array 3 is positioned on the outer surface of flexible material 5.Flexible material supports with a kind of adaptive basic material 2, and for example fiber or porous material are as sponge.The hard support 1 of adaptive part is also provided.

The embodiment that Fig. 2 illustrates device is applied to breast 4, and the shape of flexible material and basic material and breast 4 roughly adapts.Although there are some pressings in breast in this embodiment, the pressure that patient bears and uncomfortable because the adaptability installing alleviates.In addition, the electrode of greater number has increased contact.

In Fig. 3, an optional embodiment is shown, electrod-array 3 is covered by a kind of conduction overcover or film.

In use, application of installation is to target area, and brings some pressure to bear the shape of adaptive arrays and target area is adapted.Certain distortion that can scheduled target region, but compare with the hard flat array known in existing design, be minimum.The adaptive arrays of embodiment provides multi-electrode and contacting that body surfaces increases.A kind of conducting liquid may be used between device and body surfaces, can help the impedance operator between matched electrodes array and main body outer surface.In the case, or other liquid is when exist, and array can comprise conducting film outside waterproof or water resistant, thereby prevents that the contact portion of electrode is moist, unclean or damage.In addition, level and smooth film can be more prone to so that outside multi-electrode is compared in the cleaning of device with sterilization.Basic material 2 can be sponge material, and for example perforate or closed pore sponge, make device have the adaptability to target area.

In use, as the setting with reference to figure 4, electrod-array is added on patient 100, and each as receptor and in a plurality of residue electrode of in electrode one is as emitter.Electric current is applied to each emission electrode of array 102, and a receptor electrode in array receives each current signal 104.Repeat this step 106, by making receptor become transmitter electrode, and make successively transmitter electrode become receptor electrode, thereby set up for example 256 * 255 reception signal mode of 256 electrod-arrays of n electrode * n-1 electrode.The measurement data generating is like this for deduced image.Image can be established as the degree of depth " lamella " 108, and it extends through patient, spreads the width that is similar to array.Algorithm calculates a value for each voxel by these data of cause, and the image in the degree of depth can be set up thus.The further mensuration of the probability that undesired tissue occurs can calculate 108.

For undesired tissue, exist or do not exist and carry out initial assessment 110.If detected, there is no undesired tissue 112, can advise that patient returned after such as 12 months, 1 year, 2 years etc. and carries out customary examination in the regular period.Critical case can advise as after 3-6 month or only several days/week, returning to 116 examinations at a short period interval.If undesired tissue 114 detected, can advise further measuring.

Therefore,, for symptom or the appearance of undesired tissue, for example breast carcinoma or other tumor, can be in rural area or low technical region and/or undertaken by the personnel of minimum qualification to patient's examination, to provide at least initial examination.

Claims (16)

1, a method of utilizing electrical impedance (EI) whether to have undesired tissue a position examination patient, comprises the following steps:

A) obtain patient's EI measurement data;

B) by measurement data, produce view data; And

C) evaluate image data, thereby make, undesired tissue exists or non-existent mensuration for the first time.

2, method according to claim 1, comprises the following steps:

D) connection electrode array is to patient, and one in electrode as receptor, and each in a plurality of residue electrode is as emitter;

E) by each transmitter electrode, to patient, import a current signal into;

F) at receptor electrode, receive described current signal;

G) change a transmitter electrode into receptor electrode, and conversion receiver electrode is a transmitter electrode;

H) for each emitter and receptor electrode repeating step b) to d); And

I) by a plurality of signal image data generatings that receive.

3, method according to claim 1 and 2, is characterized in that, comprises measurement data is applied to a kind of algorithm, thereby produce view data.

4, method according to claim 3, is characterized in that, comprises further step: ((a) measure undesired tissue exists or non-existent probability 1+exp in algorithm, to utilize formula P=1/.

5, method according to claim 4, is characterized in that:

A=b ₀+ b ₁x ₁+ b ₂x ₂+ b ₃x ₃+ b ₄x ₄+ b ₅x ₅, wherein

X ₁patient age,

X ₂the average of original measurement value,

X ₃the intermediate value of original measurement value,

X ₄the average of view data,

X ₅it is the standard deviation of view data.

6, according to the method described in aforementioned arbitrary claim, it is characterized in that, comprise step:

By measurement data, generate a plurality of depth image layers, each image layer is to go deep into the continuous depth image of human body.

7, method according to claim 6, is characterized in that, comprises step: thus relatively Range image layer indicates undesired tissue between adjacent layer exist or do not exist.

8, the method to the body region impedance imaging of main body, comprises the following steps:

Locating at least one multicomponent pops one's head at least one respective surfaces of body region;

With two or more different frequencies, apply electrical current on the element of multicomponent probe;

The signal being obtained by different frequency on detecting element; And

Based on detection signal, generate at least one width impedance diagram.

9, a kind of electrical impedance (EI) system, comprise a kind of device, it has output device, for applying the continuous signal of telecommunication to a plurality of transmitter electrodes, described device also comprises input equipment, for receiving a plurality of described signals of telecommunication that receive as measurement data; Processor, for generating pictorial data by described measurement data; And display, for by described view data displayed map picture.

10, system according to claim 9, is characterized in that, described device comprises the device that is generated a plurality of Range images by described measurement data.

11, according to the system described in claim 9 or 10, it is characterized in that, comprise blood processor, for generated undesired tissue by measurement data, exist or non-existent probability.

12,, for a device for patient's electrical impedance examination, comprise that a plurality of different frequency signals of telecommunication of output are to patient's device; At least one input, receives the electrical impedance signal being produced by input electrical signal from patient; And blood processor, by the electrical impedance signal receiving, generate pictorial data.

13, device according to claim 12, is characterized in that, comprises the element arrays connecting removedly, and wherein each arrangements of elements is at least one signal of telecommunication of conduction is to patient.

14, according to the device described in claim 12 or 13, it is characterized in that, described blood processor comprises that the signal based on receiving generates the device of patient's multilamellar pictorial data.

15, a kind of substantially as previously mentioned for the device of electrical impedance examination.

16, a kind of substantially as previously mentioned for the method for patient's examination.

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