CN103211588A - Blood flow velocity imaging method based on transverse velocity model - Google Patents
Blood flow velocity imaging method based on transverse velocity model Download PDFInfo
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- CN103211588A CN103211588A CN2013101612759A CN201310161275A CN103211588A CN 103211588 A CN103211588 A CN 103211588A CN 2013101612759 A CN2013101612759 A CN 2013101612759A CN 201310161275 A CN201310161275 A CN 201310161275A CN 103211588 A CN103211588 A CN 103211588A
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Abstract
The invention provides a blood flow velocity imaging method based on a transverse velocity model. The method includes the steps that laser which is subjected to beam expansion is used for irradiating the body surface, and a CMOS camera is used for carrying out continuous imaging on irradiated areas; motion of red cells in shallow blood vessels of the body surface causes fluctuation of backscattering light intensity; an overall pixel matrix is used as a paralleled detector array, and each pixel in the CMOS camera is used as an independent detector; light intensity signals recorded by each pixel form an independent signal sequence, a normalized autocorrelation function of each signal sequence is calculated after continuous imaging; and the gradient of a linear area before a first zero point of the normalized autocorrelation function is the crossing time of the red cells transversely penetrating through detecting focal spots, and the transverse speed of the red cells is the transverse width of the detecting light focal spots.
Description
Technical field
The present invention relates to the blood flow imaging technical field, particularly a kind of blood flow velocity formation method based on the transverse flow speed model.
Background technology
The fast imaging that body surface shallow-layer microcirculqtory system blood flow velocity distributes, be widely used clinically, at present, the blood flow imaging technology of Noninvasive comprises: speckle technology, acoustic doppler velocimeter, laser-Doppler current meter, doppler optical coherence chromatography, based on the laser-Doppler blood flow imaging technology of high-speed cmos camera.The speckle technology can not be carried out quantitative measurement, also is not suitable for flow velocity faster, and acoustic doppler velocimeter can only be used for trunk, can't be used for microcirculqtory system.Doppler optical coherence chromatography and laser-Doppler current meter all are spot measurements, need mechanical scanning to realize that image taking speed is slow than the large tracts of land imaging.Based on the laser-Doppler blood flow imaging technology of high-speed cmos camera is improvement to the laser-Doppler current meter, the same Doppler effect that all is based on the laser-Doppler current meter, high-speed cmos camera about using frame rate as 20KHZ replaces mechanical scanning, realizes fast imaging.But the reportedly defeated processing speed of this high-speed cmos camera and needed googol makes the cost of this imaging technique very high, and it is bigger that while blood flow velocity result is influenced by the doppler angle uncertainty.
Summary of the invention
The object of the invention is to provide a kind of blood flow velocity formation method based on the transverse flow speed model, it can intermittently pass in and out the low frequency fluctuation of surveying the backscattering light intensity signal that the light focal spot causes by erythrocyte and remove to calculate blood flow velocity, with the method for the high frequency Fluctuation Calculation blood flow velocity that is caused by Doppler effect that replaces using at present.
Technical solution proposed by the invention is such:
A kind of blood flow velocity formation method based on the transverse flow speed model, this formation method comprises the steps: to use the laser 5 irradiation body surfaces 6 through expanding bundle, with 7 pairs of area to be illuminated territories of CMOS camera continuous imaging, the light intensity signal of CMOS camera 7 each pixel record forms independently signal sequence, calculate the normalized autocorrelation functions of each signal sequence, the slope in partial linear zone is that erythrocyte 1 is horizontally through the transition time of surveying light focal spot 2 before first zero point of normalized autocorrelation functions
, erythrocytic lateral velocity is
, wherein,
For surveying the transverse width of light focal spot.
Principle of the present invention is as follows: the laser 5 through expanding bundle is to shine body surfaces 6 with body surface 6 subvertical directions, carry out continuous imaging with 7 pairs of area to be illuminated territories of CMOS camera, the whole picture element matrix of CMOS camera 7 is equivalent to parallel detector array, each pixel promptly is an independently detector, writes down corresponding focus place time dependent backscattering light intensity signal.The blood circumstance at focal spot place of supposing certain pixel correspondence is shown in Fig. 1 (a), stain is represented mobile erythrocyte among the figure, the dotted rectangle frame table shows the focal spot 2 of surveying light, when erythrocyte does not enter detection light focal spot 2, the signal that reflects back is very weak, when erythrocyte 1 enters detection light focal spot 2, have stronger reflected signal, therefore be subjected to mobile erythrocyte 1 interrupted turnover to survey the modulation of light focal spot 2, backscattering light intensity signal forms pulse one by one in time, and when erythrocyte 1 translational speed was slow, the time of passing detection light focal spot 2 was longer, the pulse width that produces is bigger, when erythrocyte 1 translational speed was very fast, the time of passing detection light focal spot 2 was shorter, and the pulse width of generation is narrower, the corresponding erythrocyte 1 of the time width of pulse passes the time of surveying light focal spot 2, i.e. transition time
Among Fig. 1 (a), pass the erythrocyte 3,4 of detecting light beam in the non-focusing zone, because these erythrocyte 3,4 are in outside the focal spot 2, less to the influence of backscattering light intensity signal, therefore, focal spot 2 outer erythrocytic influences can be ignored.Rectangle frame is represented the focal spot 2 that amplifies among Fig. 1 (b), and erythrocyte is with speed
Flow through focal spot 2, survey light vertically, doppler angle is
,
Longitudinal component
Cause Doppler frequency shift, be assumed to
Erythrocyte is with lateral velocity
Pass and survey light focal spot 2, then back-scattering light can be expressed as
, suppose that the back-scattering light of stationary is around the blood vessel
, this two parts light all enters detector and interferes (being heterodyne method), and the light that then detects is
, because
Much smaller than
, the light intensity signal that then detects can be reduced to
, shown in Fig. 2 (a), the higher-order of oscillation wherein derives from Doppler effect, promptly
So,, all be that the analysis of high frequency vibration signal calculates flow velocity based on the blood flow imaging method of Doppler effect, the frame frequency of camera is required than higher, generally at 20KHZ.Low frequency envelope among Fig. 2 (a) (shown in Fig. 2 (b)) corresponding to
, the pulse among Fig. 2 (b) is exactly that erythrocyte passes and surveys the light focal spot and form, so width average time of pulse is exactly the time that erythrocyte passes detection light focal spot, i.e. transition time
, suppose that the transverse width of surveying the light focal spot is
, then erythrocytic lateral velocity
Because the frequency of the low-frequency pulse among Fig. 2 (b) is lower, therefore the frame frequency of camera is required to be not less than 500HZ and get final product.During several cycle of the higher-order of oscillation that causes greater than Doppler effect when the time of exposure of camera, then the higher-order of oscillation that causes of Doppler effect has only erythrocyte intermittently to pass in and out and surveys the low-frequency pulse that the light focal spot causes, shown in Fig. 2 (b) just by on average in the signal.
Though the transverse flow speed model can only obtain the cross stream component of flow velocity, promptly
,
Be actual flow velocity,
Be doppler angle because body surface shallow-layer blood vessel major part all is and body surface near parallel distribution, when imaging system and irradiating laser and body surface when vertical, doppler angle
Scope between 90 °～80 °, then the scope of flow velocity cross stream component exists
Between, very near actual flow velocity
So, can represent actual flow velocity with transverse flow speed, need not consider the influence of unknown doppler angle, be the longitudinal component of flow velocity and the present blood flow imaging method based on Doppler effect obtains, promptly
, work as doppler angle
Scope exist
In the time of between the degree, the result is
, and actual flow velocity
Differ bigger, can not reflect true flow velocity.
For the signal shown in Fig. 2 (b), calculate the mean breadth of pulse, i.e. transition time by normalized autocorrelation functions
,
In the following formula
The auto-correlation function of the light intensity signal that expression detects.
The low frequency envelope signal that Fig. 3 (a) and (b), (c) detect when representing the flow velocity ratio for 4:2:1 respectively, though under same speed, the width and the amplitude of the backscattering light pulse that erythrocyte produces when passing detection light focal spot are variant, but the width of flow velocity and pulse has tangible dependency.The normalized autocorrelation functions of Fig. 3 (a) and (b), (c) is shown in Fig. 3 (d), the result that the corresponding respectively flow velocity ratio of cross hairs, solid line and dotted line is 4:2:1, choose that the reasonable zone of the linearity is as slope computer capacity (being that ordinate value is the scope between 0.2～0.8) between two horizontal dotted lines, the inverse of the slope of three's correspondence (is the transition time
) ratio be 19:10:6, the ratio of transverse flow speed is that 1:1.9:3.2 and flow velocity are identical substantially.
Compared with prior art, the present invention has following remarkable result:
(1) the present invention proposes a kind of computation model of flow velocity cross stream component, intermittently pass in and out the low frequency Fluctuation Calculation flow velocity of surveying the backscattering light intensity signal that the light focal spot causes by erythrocyte, the method of the high frequency Fluctuation Calculation flow velocity that causes by Doppler effect that replaces using at present, make minimum requirements be reduced to 500HZ, thereby reduced requirement CMOS camera and data transmission and processing speed by existing 20KHZ to CMOS camera frame frequency.
What (2) this method was measured is the flow velocity cross stream component, and Doppler's method is measured is the flow velocity longitudinal component, body surface shallow-layer blood vessel major part all be and body surface near parallel distribution, the flow velocity cross stream component be subjected to doppler angle probabilistic influence less, thereby, more approaching real blood flow rate.
Description of drawings
Fig. 1 (a) is based on the blood flow velocity imaging schematic diagram of transverse flow speed model, and the expression erythrocyte is flowed through and surveyed the sketch map of light focal spot 2 among the figure.
Fig. 1 (b) is the enlarged drawing of the detection light focal spot shown in Fig. 1 (a).
The light intensity signal that Fig. 2 (a) expression CMOS camera detects.
The light intensity signal that Fig. 2 (b) expression detects is removed the envelope of the higher-order of oscillation.
Fig. 3 (a) expression flow velocity ratio is the envelope that the light intensity signal that detected in 4 o'clock is removed the higher-order of oscillation.
Fig. 3 (b) expression flow velocity ratio is the envelope that the light intensity signal that detected in 2 o'clock is removed the higher-order of oscillation.
Fig. 3 (c) expression flow velocity ratio is the envelope that the light intensity signal that detected in 1 o'clock is removed the higher-order of oscillation.
The normalized autocorrelation functions of the low frequency envelope that Fig. 3 (d) expression detects according to Fig. 3 (a), Fig. 3 (b), Fig. 3 (c).
Fig. 4 is based on the structural representation of the blood flow velocity imaging device of transverse flow speed model.
The specific embodiment
By following embodiment the present invention is further elaborated.
Referring to shown in Figure 4, a kind of blood flow velocity imaging device based on the transverse flow speed model is made up of laser instrument 10, beam expanding lens 9, imaging system 8, CMOS camera 7 and computer 11.Object 6 to be measured is a body surface for the blood flow on palm top layer, the laser that laser instrument 10 sends is irradiation body surface 6 after beam expanding lens 9 expands bundle, the laser 5 that expands bundle is approaching vertical with body surface 6, imaging system 8 makes the irradiated area image in CMOS camera 7, the image of computer 11 control CMOS cameras 7 continuous acquisition imaging regions, each pixel conduct of CMOS camera 7 is detector independently, writes down corresponding focus place time dependent backscattering light intensity signal.The focus point of supposing pixel 12 correspondences is 13, and the signal that pixel 12 collects is
, calculate
Normalized autocorrelation functions, the slope in partial linear zone is that erythrocyte 1 is horizontally through the transition time of surveying light focal spot 2 before first zero point of normalized autocorrelation functions
, calculate the transition time that erythrocyte passes 13 focal spots 2 with formula (1)
, then transverse flow speed is
, here
Be to survey light focal spot 2 transverse widths.
Survey light focal spot 2 transverse widths
Measure by following method: be with a known flow rate
Stripped blood flow as sample, regulate light beam and blood flow flow direction near vertical, then according to above-mentioned same method, measure the time that erythrocyte passes detection light focal spot 2
, then can obtain
Therefore, transverse flow speed is
Signal sequence to CMOS camera 7 each pixel record is all handled according to above method, then can obtain the blood flow rate distributed image of whole imaging region.
The parameter based on the blood flow velocity imaging device critical piece of transverse flow speed model that is used for this method is as follows: the frame frequency of CMOS camera 7 is 500HZ; The time of exposure of selecting CMOS camera 7 is that second 100 is delicate.
Claims (1)
1. blood flow velocity formation method based on the transverse flow speed model, it is characterized in that: this formation method comprises the steps: to use through expanding laser (5) the irradiation body surface (6) of bundle, with CMOS camera (7) to area to be illuminated territory continuous imaging, the light intensity signal of each pixel record of CMOS camera (7) forms independently signal sequence, calculate the normalized autocorrelation functions of each signal sequence, the slope of the range of linearity is that erythrocyte (1) is horizontally through the transition time of surveying light focal spot (2) before first zero point of normalized autocorrelation functions
, erythrocytic lateral velocity is
, wherein,
For surveying the transverse width of light focal spot.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106054159A (en) * | 2016-05-12 | 2016-10-26 | 北京航空航天大学 | Instantaneous frequency extraction method of Doppler signals |
| CN106419890A (en) * | 2016-11-14 | 2017-02-22 | 佛山科学技术学院 | Blood speed measuring device and method based on space-time modulation |
| CN109924969A (en) * | 2019-04-19 | 2019-06-25 | 优谱激光科技(南京)有限公司 | A kind of laser imaging blood perfusion detection device with light probe |
| CN110192852A (en) * | 2019-06-18 | 2019-09-03 | 东北大学 | The flow velocity cross stream component measuring system and method for dual scanning line optical coherence tomography |
| CN106419890B (en) * | 2016-11-14 | 2024-04-30 | 佛山科学技术学院 | Blood flow velocity measuring device and method based on space-time modulation |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006520900A (en) * | 2003-03-11 | 2006-09-14 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Spectroscopic analysis apparatus and method comprising an excitation system and a focus monitoring system |
| US20100094110A1 (en) * | 1998-04-30 | 2010-04-15 | Abbott Diabetes Care Inc. | Analyte Monitoring Device and Methods of Use |
| WO2011026393A1 (en) * | 2009-09-07 | 2011-03-10 | Zhang Naiqian | Semiconductor device and fabrication method thereof |
| WO2011097631A2 (en) * | 2010-02-08 | 2011-08-11 | Oregon Health & Science University | Method and apparatus for ultrahigh sensitive optical microangiography |
| CN102657519A (en) * | 2012-05-11 | 2012-09-12 | 浙江大学 | OCT (optical coherence tomography)-based high-sensitivity measurement system and method with large dynamic range of flow speed |
| CN102657518A (en) * | 2012-04-19 | 2012-09-12 | 中国科学院上海光学精密机械研究所 | Method of complex frequency-domain optical coherence tomography using differential sinusoidal phase modulation |
-
2013
- 2013-05-06 CN CN201310161275.9A patent/CN103211588B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100094110A1 (en) * | 1998-04-30 | 2010-04-15 | Abbott Diabetes Care Inc. | Analyte Monitoring Device and Methods of Use |
| JP2006520900A (en) * | 2003-03-11 | 2006-09-14 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Spectroscopic analysis apparatus and method comprising an excitation system and a focus monitoring system |
| WO2011026393A1 (en) * | 2009-09-07 | 2011-03-10 | Zhang Naiqian | Semiconductor device and fabrication method thereof |
| WO2011097631A2 (en) * | 2010-02-08 | 2011-08-11 | Oregon Health & Science University | Method and apparatus for ultrahigh sensitive optical microangiography |
| CN102657518A (en) * | 2012-04-19 | 2012-09-12 | 中国科学院上海光学精密机械研究所 | Method of complex frequency-domain optical coherence tomography using differential sinusoidal phase modulation |
| CN102657519A (en) * | 2012-05-11 | 2012-09-12 | 浙江大学 | OCT (optical coherence tomography)-based high-sensitivity measurement system and method with large dynamic range of flow speed |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106054159A (en) * | 2016-05-12 | 2016-10-26 | 北京航空航天大学 | Instantaneous frequency extraction method of Doppler signals |
| CN106054159B (en) * | 2016-05-12 | 2018-09-11 | 北京航空航天大学 | A kind of instantaneous frequency distilling method of Doppler signal |
| CN106419890A (en) * | 2016-11-14 | 2017-02-22 | 佛山科学技术学院 | Blood speed measuring device and method based on space-time modulation |
| CN106419890B (en) * | 2016-11-14 | 2024-04-30 | 佛山科学技术学院 | Blood flow velocity measuring device and method based on space-time modulation |
| CN109924969A (en) * | 2019-04-19 | 2019-06-25 | 优谱激光科技(南京)有限公司 | A kind of laser imaging blood perfusion detection device with light probe |
| CN110192852A (en) * | 2019-06-18 | 2019-09-03 | 东北大学 | The flow velocity cross stream component measuring system and method for dual scanning line optical coherence tomography |
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