FR2481454A1 - APPARATUS AND METHOD FOR EXPLORING BIOLOGICAL MATERIALS - Google Patents

Abstract

THE APPARATUS INCLUDES A SOURCE 50 OF NON-IONIZING ELECTROMAGNETIC RADIATION, MEANS 52 FOR APPLYING THE RADIATION OF THIS SOURCE TO A BIOLOGICAL MATERIAL THAT WE DESIRE TO EXPLORE AND MEANS 58 FOR QUANTITATIVELY DETECTING THE ABSORPTION AND RADIATION CHARACTERISTICS THE SAID MATTER.

Description

248 1454

The present invention relates to an apparatus and method for the quantitative measurement of absorption, refraction and diffusion, as a function of length.

  wave, biological tissue, especially human tissue

  living hand, using non-ionizing radiation9 Known methods of exploring human tissues in order to detect the internal structure underlying the tissues have used various techniques using X-rays, axial tomographic X-rays controlled by computer,

  thermographic and ultra-technical

  sounds. While X-rays provide good images of the internal structure of the body, they are dependent on ionizing radiation, which poses a carcinogenic risk to the patient. This risk is of particular importance

  when detecting lesions of the chest and more

especially from the breast. Quite apart from the risks of radiation dosimetry associated with the use of X-rays, the use of these rays is inefficient from the energy point of view. More specifically, in this regard, it can be said that a conventional X-ray tube comprises a set

with anode and cathode mounted in a glass envelope inside

inside which the vacuum has been established, the anode is in general

  usually a massive piece of copper in which is placed

  a small tungsten target. The cathode generally includes

  ral a tungsten wire filament placed in a shallow focusing bowl, The hot tungsten filament provides the source of electrons which are accelerated towards the anode

  by applying a high voltage between the anode and the cathode.

  Even in the most favorable cases, the radiation rate

active of such a set represents only 1 or 2% of the e-

  total energy of electrons. In other words, most of the energy is dissipated in the target in the form of collision energy or heat. In addition to the aforementioned drawbacks of X-ray techniques for the exploration of living tissue, appropriate protection and an exact direction of an X-ray beam, comprising the use of a diaphragm and orifices, are necessary to obtain

the exposure of a usable film or a treatment

  satisfying. The use of thermographic techniques in

exploration of human tissue, while using energy

Non-invasive infrared technology, has various disadvantages

  which make this technique unsatisfactory as a mo-

diagnostic yen, especially in the case of lesions of the poi

trine and in particular of the breast. In the event of detection of a lesion of the chest, one does not generally trust the

single thermography and we normally complete it with a mam-

  mography. One of the reasons for using the techniques

X-ray in conjunction with thermographic processes

  ques to detect lesions of the chest is based on the problem of maintaining the machine used for the techniques

  thermographic in a sufficiently stable state to allow

  put quantitative and reproducible measurements. The significant gain in amplification required to convert infrared radiant energy into a display makes the system

  highly sensitive to device drift. A slight de-

  The sensitivity of the detector causes a change in intensity of the display relative to the temperature of the surface being explored. Quite apart from this

problem, you must use a refrigerant such as nitrogen

just to keep the temperature of the radiation energy detector at appropriate intervals. This aspect of

  the technique requires the use of large quantities of

  energy to maintain a temperature of -1980C, that is to say the temperature at which nitrogen is in the liquid state. The

  thermography still has the disadvantage of not per-

  put to detect and locate small lesions in thick living tissue such as the human chest. In this respect, insufficient infrared radiation is emitted by small bodies of this kind, so that the infrared-sensitive unit in such equipment does not make it possible to detect a significant change in the temperature of the tissue caused by

little bodies like this.

  Ultrasound techniques are limited in application.

cation through attenuation and interaction of ultrasound with the tissue being explored. In addition, ultrasound is the source of certain biological risks such as

  platelet aggregation which appears at lower levels

laughing at those who cause thermal damage. According to the invention, an apparatus has been developed

  and a method for non-invasive examination of human tissue

  hands that can effectively remove

  risks involved in the use of techniques to

xons and ultrasound techniques which also overcome the problems inherent in the use of thermographic diagnostic techniques. The current

  subject of the invention is the quantitative measurement of the transmission

  vision and reflection of visible light and light

re infrared and it involves passing light with various selected wavelengths through

  a tissue being studied and measure the intensity of the lu-

matter transmitted or reflected with respect to the intensity of the light sent, thus allowing the measurement of the index of

  refraction, absorption and diffusion of tissue, The invention

  tion takes advantage of the fact that various types of fabrics, such

  that fats, muscles and tumors differ significantly

  in absorption, refraction and diffusion characteristics with respect to visible light and infrared light. The contrast between various tissues can be enhanced by a judicious choice of wavelengths used for measurement. Information about the type of tissue and its metabolic state can be obtained by measuring the amount of light transmitted or reflected at various wavelengths and comparing these values with previously established standards by direct measurement in human patients who then have biopsy documentation from

the nature of the tissue examined. According to one of the embodiments, -

tion, the device according to the invention uses a network of detectors to record in a differential mode the flux of photons in the central zone which corresponds to the portion of the detector illuminated to the maximum by the light beam when the tissue is not interposed for serve as a diffusion medium and one or more concentric rings of active detector surface which receive the light having been

diffused to varying degrees from the central detector.

  This provision allows separate registration of zones

  central and peripheral thereby providing information

additional information regarding the intensity of the diffusion

as well as the degree of refraction and absorption at this length

particular waveguide. The information of each of the

  concentric vectors is recorded separately and remains available for additional manipulations such as reporting. In its simplest form, this embodiment of the invention comprises a central detector having the dimensions of an undispersed beam and a

  or more concentric peripheral detectors. A va-

This embodiment consists of a network of electronic detectors comprising multiple elements, so that a map of tissue diffusion signatures can be established, this map being specific to the transillumination of water, blood, fats, muscles, cancer

breast, skin, speckles of calcium and other elements

  transillumination elements both simple and complex.

Such complex tissue signatures can be emma-

  stored in a digital or analog memory and we can

  compare them with newly received signals. Changes-

items in broadcast reports can be used as a

general in image and imageless systems.

  According to another aspect of the invention, a quantitative transmission of exploration or reflection is used.

visible light or infrared light to pro-

  make a profile projection image. In this embodiment of the invention, the quantitative system of

transmission or reflection described above is successi-

  moved along the fabric being explored to establish an image in a point mode. The exploration is advantageously carried out by conventional rectilinear techniques which use a photo-exposure device

2 48 1 454

  mechanically coupled to the light source and the detector.

  Alternatively, a photographic recording can be obtained

by electronic coupling of the XY position of the ex-

  ploration with the XY location of the electron beam of a cathode ray tube taking into account the duration

exhibition of the photographic film, In such a structure-

  electronically, the XY position of the beam is determined

born by the XY position of the explorer head, and the intensity

  sity of the electron beam current is proportional to the number of photons detected by the detector head

Another aspect of the invention relates to the trans-

quantitative mission and reflection of visible light

  and infrared light at specific wavelengths

  to enhance the distinction between the various fabrics in

  combination with a digital memory or a picture tube

  image sinning, so that multiplication, division, addition or subtraction of images can be performed in digital form using memory

digital, or in analog form on a storage tube

  sinage of images. The individual images worn by diver-

its wavelengths can be displayed as part of a multispectral imaging process, which

can display in gray mode, or according to a color display

their in which the image data for a particular wavelength is assigned to a pistol or cannon

  particular color of a three-way video display

  colors. By multispectral techniques of

  treatment, the distinction between various tissues or various cQm-

  tissue tissue or physiological information such as the oxidation state of various tissue portions may be

demonstrated and registered.

  According to another aspect of the invention, use is made

a kind of reconstruction using a computer and this

this is based on multiple images each of which has been pro-

pick from a point source different from transmitted-

  light reflection or reflection. The reconstruction process

  tion and processing with computer is analogous to that used

  read in axial tonographic systems with computer of the type commonly used with X-rays.

  fabrics under review are lit from a multi-

plicity of points by a moving light or a network of switched sources, The diagram of the image which one obtains by

  illumination from each point is detected by a system

  appropriate detector such as for example a “vidicon”

  frarouge Hammamatsu and we treat him for a correction

  uniformity of the field before storing it in a mete

  electronic memory. The diagrams of the images are stored

together with the XY coordinates of the lightning point-

  where the transillumination comes from. These ima-

  ges are treated by a technique consisting in reprojecting them

  mathematically to obtain a tomQgraphic series of ima-

  ges. An advantage of this system is that the spatial relationship of the objects can be confirmed in depth and also that the resolution is much more marked with greater photon efficiency than can be achieved by a mode.

straight exploration.

  The apparatus according to the invention, under its Jorme fonda-

  mental, includes a light source, detection means

tion of light and signal display means.

  In its more improved form, the apparatus comprises a light source, means for selecting the wavelength, light transmission means, optical alignment means, light collecting means,

  light detection means, amplification means

  signal cation, signal comparison means and signal display means, The term "light" used

in the present specification designates visible or infra-light--

non-ionizing red having a wavelength between approximately 400 and 700 nm respectively and between approximately 700 and 106 nm. Preferred values range from around 600 nm for

  visible light at around 1400 nm for infrared light

red.

  The light sources that are used for the setting

  of the invention include a projection bulb

  halogen-quartz filament torch, xenon arc lamp, arc lamp, xenon-mercury, photo7 emitting diodes, tunable lasers, or even ordinary light, Choice of length Coma waves advantageously take thin film, wide or narrow band optical filters having peaks between approximately 450 nm and approximately 1350 nm with intervals of 50 nm. One or more monochromators can also advantageously be used. The means for transmitting or transmitting light comprise flexible bundles of optical fibers, rigid light guides or conduits, said means being capable of transmitting the lengths

  of waves considered, the detector means used include

  are silicon or germanium photodiodes, tubes

  photomultipliers, "vidicons" and si-

milaries.

  Various other features of the invention

  moreover emerge from the detailed description which follows.

  Embodiments of the object of the invention are shown, by way of nonlimiting examples, in the appended drawings, FIG. 1 shows the propagation of light through a relatively homogeneous human tissue showing

  the effect of the interaction of light with an absorbing body

  solid-in-tissue, the waveforms being represented "-

  felt like lines of isolation.

  Fig. 2 is a view similar to Figure 1 except

  that the solid absorption body is at a greater dis-

  tance of the light entry point, Figs. 3 and 4 are respectively a top view and a side view showing the light which enters at two different points to produce lines of isoluminance which are projected in the form of shadows in FIG, 3, FIG. 5 is a perspective view of a mode

for producing the apparatus according to the invention.

  Fig. 6 is a perspective view, partially

ment torn off, showing an embodiment of a head

  rectilinear exploration for the implementation of the invention

tion. Fig. 7 is an exploded view, partially in section, of a light emitting unit for supporting and transmitting light through a human chest and more particularly a breast, Figs. 8A and 8B are respectively side and top views of an embodiment of the apparatus

using a rectilinear exploration head of the type represented

  felt in fig. 6, together with a spoke tube

  cathodics established to explore a human chest.

  Figs. 9A and 9B are respectively a view

  side view and top view of the light emitting unit

shown in fig. 7 used in combination

  sound with an axial tomography device with computer control for exploring a human chest,

At the outset, it should be noted that he was

  shown that biological materials are transparent

  relatively good in the infrared region of the spectrum,

which allows sufficient photon transmission through

  to the human tissue being examined in order to perform the

  event detection even in relatively thick areas-

  his. Thus Franz F. J5bsis in an article entitled "Nonin-

vasive, Infrared Monitoring of Cerebral and Myocardial Oxygen Sufficiency and Circulatorv Parameters ", published in the journal" Science "of December 23, 1977, volume 198, pages 1264-1267, states that" the relatively good transparency of biological materials in the near infrared region of the spectrum allows sufficient transmission of photons through the organs examined for the control of intracellular events ", The article by J8bsis has sufficiently studied the control of

  oxygen in the tissues. Using light sources

  its intense and a photomultiplier tube, Jtbsis managed to detect infrared light crossing 13 centimeters

  of the human brain through the skull and scalp.

With particular reference to FIG. 1, the propagation of visible red light or infrared light through relatively homogeneous tissues which are capable of intense light scattering and which contain a light absorbing object is illustrated by waveforms which are will call lines of isoluminance, The light enters the fabric 10 in 12 in the form of a

narrow collimated monochromatic beam. The isolation line

  minance 14a defines the contours of an equal luminosity having been produced by the contribution of light at point 12, The lines of isoluminance 14b and 14c represent the contours of the lines of isoluminance at increasing distances from the initial entry point of light 12, the line of isoluminance 14d represents the distribution of the intensity of the light after

  interaction with a light absorbing object 16o The li-

  gne of isoluminance 14e describes the progressive process of pro-

  jection of the shadow by the light absorbing object 16 due to the intense diffusion in the tissue 10.o The line of isolance 14f, at a considerable distance from the point of entry of light 12 and from the absorbing object light 16 has a shallow recess 18 in the outline

  isoluminous under the effect of the presence of the object of absorp-

  tion of light 16. The center 18a of the recess is due to the absorption by the object 16 and represents a minimum of

brightness, while the border 18b of the recess represents

feel a maximum of brightness, A detector such as a pho-

  silicon diode or an array of silicon photodiodes (not shown), on the side of the fabric 10 opposite to that

  from the point of light 12 overhanging the recess

  ment 18 in the line of isolance 14f, makes it possible to measure the transmission of light through the fabric 10 when this transmission is affected by the presence of the object 16 absorbing the light o A detector of a format sufficient to present a sensitive surface separate covering areas 18a and 18b of recess 18 would provide a useful report

  between the brightness in 18a and in 18b to allow

tect the object 16.

  Fig. 2 is similar to FIG. 1 except that the light entry point 20 is at a greater

  distance from the light absorbing object 22. As above

  demment, the contribution of light produces a series of lines of i

soluminance 24a, 24b, 24c, 24d, 24e and 24f before the interaction

  tion with the light absorbing object 22, Line 24g represents the distribution of light intensity after interaction with the light absorbing object 22, Since the object 22 is close to the top surface of the fabric 10 , the recess 26 in the 24 hour isoluminance line is very large compared to that shown in the

fig. 1 or a greater distance was expected between the ob-

jet 16 and the upper surface of the fabric 10. In the re-

  presentation of fig. 2, there is a greater difference

  between the level of the light on the edge 26b of the recess 26 and the center 26a of the recess. The

object detection 22 can be performed by the same tech-

  nique that that described in connection with fig. 1,

  Figs. 3 and 4 are respectively a side view

  rale and a top view showing the lines of insulation produced in a section of tissue 30 with intense light diffusion and containing two different objects of light absorption 32 and 34 when the light is introduced at two points 36 and 38. The isoluminance lines from the

  point 36 are indicated in dashes while the lines of iso-

  luminance from point 38 are shown in solid lines. The lines 36a, 36b and 36c coming from point 36 define, as before, a recess 40 which is detectable as indicated at 32a in FIG. 3. However,

  the lines of insulation 36a, 36b and 36c also deviate

  laterally fan-shaped in the direction of the object 34 and form a recess 42 which is detectable in the form of a shadow of the object 34, as shown at 34 'in FIG. 3. Likewise, the lines of isolance 38a, 38b,

  38c, 38d and 38e from point 38 provide a

  darkly detectable 44, due to absorption of

  object 34. The shadow 34a thus produced is detected

table as shown in fig. 3, Just as with the isoluminance lines coming from point 36, the isoluminance lines 38a, 38b, 38c, 38d and 38e coming from point

  38 are intercepted and absorbed by the object 32 to defi

  nir a recess 46 aui is detectable in the form of a shadow 32 'as shown in fig, 3, It is thus possible not only to detect the presence of the two objects 32 and 34 in the tissue 30, but also to locate with precision the areas of the '30 fabric where these objects are placed, by

  means of back projection or rear projection.

The embodiment of the device according to the invention

  tion, which is shown in fig. 5, comprises an assembly, forming a light source and a member for selecting the wavelength, and which is connected by a flexible bundle of optical fibers or a light guide 52 to a member 54 carrying a photodetector and which is, in turn, connected by a cable 56 to a reading element 58 at

  digital photometer, The set 50, forming the source lu-

  miner and the wavelength selector,

takes a box 50a in which is mounted an infrared light source such as a quartz halogen-tungsten lamp (not shown). A control button 50c

of variable intensity is provided on the boot 50a to

adjust the intensity of the beam emitted by the lamp. A filter wheel 60 is rotatably mounted on the case 50a by means of a shaft 50b. Advantageously, the wheel 60 comprises several interference filters 6Oa with thin film, wide band and in a concentrated arrangement, each filter having a different peak between 450 and 1350 nm with intervals of 50 nmo Narrow band filters can be used to discriminate even better among the methods detected using the device, The input facet 52a of the light guide in optical fibers 52 is held in position relative to the lamp and relative to a selected filter 60a to 1 using a connected 62 collar

  to an amount 64 itself fixed to the base of the housing 50a.

The member 54 carrying the photodetector comprises, as shown, a short fixed end upright 54a and a long fixed end upright 54b held in a fixed relationship spaced by two rods with smooth surfaces 54c54c and an externally threaded rod 54d carrying an adjustment button 54j . A mobile "54a" is placed between the amounts

  54a and 54b and it is adjustable in either direction

  tion on rods 54c-54c and 54d by a simple rotation

of button 54, A correctly calibrated measuring device

  born 54f is fixed by its ends to the fixed uprights 54a and 54b. A 54g indicator is attached to the 54th mobile station

and it is intended to slide along markers on the dis-

positive 54f when moving the upright 54e. The extreme

fiber optic guide output outlet 52 passes through

towards a bore in the outer end of the movable upright 54e and is fixed to a disc 66, A locking screw 68 maintains the inlet end of the guide 52 in position relative to the upright 54e. The fixed long upright 54b includes

an adjustable 54h head which carries a photodetector, in this case

  a semiconductor photodetector 70 of the pho- type

  silicon diode. The 54h head is fitted with a mole-

  adjustment tee 54i to allow the photodetector 70 to be aligned with the output end of the fiber optic guide 52. The input cable 56 connects the photoconductor

70 at the digital photometer reading element 58. The-

  element 58 has selection buttons 58a for defining

  finish the display factors that are visible through

a window overhanging a liquid crystal display 58b.

  Using the device shown in fig. 5, a human chest and particularly a breast comprising a palpable tumor is comfortably compressed between the disc 66 and the photodetector 70, The measuring device 54f indicates the exact distance between the outlet end of the

  guide 52 and the protodetector 70 and, by way of

  quence, the thickness of the tissue through which the light pro-

coming from a source arranged in the boot 50a. We ob-

  holds readings on the readout element 58 by passing light, at different wavelengths, from the source through the tumor in the chest. Using

the same wavelengths, we then pass the

  source from across the chest area (s)

away from the tumor. Since the degree of diffu-

  light and absorption at a wavelength given by a cancer body is much more important than that

* produced by a benign body or by a healthy fatty tissue, the na-

  ture of the palpable tumor is easy to determine from

  of the information displayed by the reading element 58. Referring now to FIG. 6, the embodiment of a head

straight exploration, which is

  represented and which bears the overall reference 80, comprising

  takes a lower fixed part 80a and an upper mobile part 80b which is vertically adjustable relative to the part 80a. At one end, the parts 80a and 80b define two parallel plates 82 and 84 between the

which one compresses a human chest to be examined

  born. The lower part 80a of the exploration head comprises a housing 80c in which is mounted an infrared light source, for example a halogenated quartz bulb 86 associated with a reflector 88, A rotary filtering wheel 90 is mounted on a shaft above the bulb 86 and the reflector 88. As well as the wheel of the apparatus shown in FIG. 5, the wheel 90 is intended to accommodate a series of optical filters 90a with a narrow or wide band, arranged concentrically in cavities

around the wheel. An area of the wheel 90 cross-

a recess or slot formed in the posterior wall of the

  exploration device to allow the operator to se-

  easily select the desired filter 90a for inves-

tigations of the tissues, The light Drovenant of the bulb 86 crosses a selected filter 90a and is admitted in

  the entry end of a flexible bundle of opti-

  ques 92 held in position on the bootmaker 80c using

  an 80d fitting. The optic beam exit end

  that 92 is fixed in a coupling 94a mounted on the end

  upper section of an upright 94, The coupling 94a also receives the entry facet of a rigid pipe 96 of

  light guide, sliding in an alignment element

  98 and ending at the bottom surface 84 or above

  face of the adjustable upper plate 80b of the head of

ploration 80 which comes into contact with the chest. The

  exit facet 96a of the pipe 96 has before-

  carefully a Variable opening (not shown) to allow

  put to adjust the diameter of the light beam passing through the optic fiber bundle 92 and the pipe 96 at the location of the exit facet of this pipe 96 for guiding the light. Below and in opposition to the

  exit facet 96a of the light pipe 96 is shown

  tee a photoreceptor -100 having a variable aperture a to adjust the diameter of the light beam admitted into the photoreceptor 100, Advantageously, the photoreceptor

  100 is a silicon photodiode and it is mounted on the former

end of an alignment shaft 102. The shaft 102 passes through a bore in an alignment member 104 and is engaged in

  a single-piece coupling 94b provided at the lower end

  amount 94. The coupling 94b is fixed to a handle

  internally fluted cap 106 which receives a tree of

  externally grooved drag 108. The shaft 108 is

  driven by a motor 104a carried by the alignment member-

  104 and it is fluted so as to produce a combined helix with dextrorsum and sinitrorsum directions in such a way

  only after the completion of its course in one or the other di-

  rection along the drive shaft 108, the sleeve 106 automatically reverses the direction of its travel. As the shaft 108 rotates, the upright 94, the pipe

to light 96 and photoreceptor 100 are simultaneous-

  ment moved in the same direction of progression as the upright 94. At each front and rear end point of the movement, an exhaust or switch (not shown) moves the

  light pipe 96, the shaft 102 and the alignment members

  98 and 104, by a precise distance on the sliding guides

114-116, by means of a stepwise rotation of the llOallOa toothed wheels on the toothed tracks 112-112. Each end of the shaft 110 has a toothed wheel 11Oa-lîQa and these wheels progress on parallel toothed tracks

  112-112. Thus a two-dimensional surface can be explo-

  driven by forward and backward progression and pro-

  lateral gression of the exit facet 96a of the pipe

96 and photoreceptor 100 in response to movement of the ar-

drive bre 108 and shaft 110 with toothed wheel,

Surfaces that come in contact with the poi-

trine on the plates 82 and 84 are advantageously formed from a transparent plastic material to allow the exit facet 96a of the light pipe 96 and the variable opening 100a of the photoreceptor 100 to move relative to the chest without establishing any direct contact. The alignment of the movable elements of the head 80 is maintained by the parallel aligned tracks 114 and 116 respectively. The whole of the upper part 80b of the exploration head 80 can move vertically

relative to the lower part 80a so as to accept

  ter a chest of almost any size.

The upright 94 and the shaft 110 are grooved to allow free movement upwards and downwards from a distance of between approximately 2.5 and 10 cm) A power transmission belt 120 of the toothed type and

with manual drive is connected to height adjustment screws

tor (not shown) placed in the corners of the head

80 to allow you to adjust the

  space between the transparent plastic surfaces of the elements 82 and 84o A shaft 122 is used to connect the exploration head 80 to an exploration console 130 (see fig. 8A and 8B) o A cable 124 carries two sets of electronic signals to a 132o image console A set of signals relates to the absolute intensity of the light detected by the 100o photoreceptor The other set of signals relates to the absolute XY position coordinates of the facet of

  output 96a of the light pipe and the aperture

riable lOa of the photoreceptor, These sets of electric signals

  tronic ensure the intensity modulation towards a beam of a cathode ray tube and the location setting towards this beam, As we can see in fig 8A and 8B, the chest of a patient 134 is compressed in the head exploration 80 which is connected by the shaft 122 to a support column 130a, An operator 136 communicates by means of a keyboard 138 with the electronic controls to produce an image and an alphanumeric affiigate on the cathode ray tube 142 , Images on photographic film are produced by a multi-format image producing apparatus -44 Fig. 7 shows an apparatus fThe light transmission comprising a basic / SD element and a chest support element 152, Element 359 _Tarte a light source such as a tartz lagné bulb (not shown) installed in a reflector EnI 354 7T filter wheel 156 is mounted in rotati = na, desss su reflector 154 and comprises a series of f'1 - your tis 156a arranged concentrically on the periphery of = nne, Part of the outer border of the 2r = e R355 te outward through a slot 150a farmióe dazs the side wall of the organ for facilitesr -the n-vatin of the wheel. A light pipe 158:! Wide facet of light entry in position adjacent to the line 156 and in opposition to the light source is mmtx- ains element 150. The pipe 158 is branded with mna. ire to provide two light output facets 3B = a and BB which are closed by an opening wheel den: e 1- ED: has light pipe 158, its facets of srtfie 2, a'et = 51Bb and the perforated wheel 160 revolve around drmn al = _re renx 162 driven by a belt 164 coupled that -m "iUre

  drive 166 and a motor 168. The member J152 comprises

  wears rod down 152d plunges into 17xeie

  hollow 162 of element 150, Element. 152 t. -

to allow examination of the patient in strong c = ndiRtinns nnn, The upper surface 152a of IilMment 152

  presents several punctual openings.

152b which are regularly spaced, Each orifice 152b is aligned with the light exit facets 170a of an equal number of light-emitting fiber beams 170, The light entry facets 170b are adjacent to rows spaced from openings 152c formed in the lower surface of the element 152, In operation, the light-emitting facets 158a and 158b

17 2481454

of the pipe 158 and the perforated wheel 170 rotate in such a way that the outside and inside rows of the openings 152c and their associated facets of entry of

  light 170b optical fibers 170 successively receive

  signal timing, A timing signal 168 is sent to an axial tomography device 180 with computer (see

fig. 9A and 9B).

  As can be seen in Figs. 9A and 9B, a pa-

  held 182 is seated so that her left breast is compressed between the upper surface 15-2a of the element 152

  and a light exclusion cone 184, The tomographic apparatus

axial phique with computer g which is represented schematically-

  ment, comprises image receiving means comprising a

television camera 186 of the type compatible with a computer

  nator. A caliper 188 maintains optical alignment, A

shaft 190 allows rotation around the axis and the movement

  vertical is possible along a support column

  192. An operator 194 manipulates a keyboard 196 to understand

  communicate with the computer and display images

  and alphanumeric signals on a cathode ray tube.

  The computer 200 comprises several modules comprising in particular an analog-digital video converter 202, an interface 204 between the camera and the computer and a storage unit 206 of images. The images 208 are actuated by a uniformity connection module 210 and are sent to a memory 212. When the family of images coded on the light points coming from the output facets 170a of the element 152 has been acquired, a image reconstruction algorithm 214 works on images in

  question to create an image projected back and recons-

  computer trout. This image appears on a control

  their 216 for displaying television images and at the same time on a high resolution video screen of a multiple format film forming apparatus 218 for producing chest slides on the element 52 having the

  same appearance as conventional mammograms.

  Although the invention has been described in connection with the

detection of human chest lesions and in particular that

breast, it goes without saying that it can be used to control

  the change in optical absorption and light scattering by the lungs and other accessible tissues, and also to form images of the lungs and the brain and other parts of the body of a human or d 'an animal.

Claims (2)

  1 apparatus for exploring biological materials, characterized in that it comprises a source of non-ionizing electromagnetic radiation, means for applying the radiation from this source to a biological material which it is desired to explore and means for quantitatively detecting the absorption and diffusion characteristics of the ray? by said material.   2 - Apparatus according to claim 1, characterized in that the detection means comprise a detector at a variable opening.   3 - Apparatus according to claim 1, characterized- in that the detection means comprise several details   independent tectors arranged concentrically or in a network, 4 -An apparatus according to claim 1 characterized in that non-ionizing electromagnetic radiation comprises   takes visible light whose wavelength is   taken between about 400 and 700 nm or an infrared light whose wavelength is about 700 at lxlO6nm0 e 5 - Apparatus according to claim characterized   in that the source of non-ionic electromagnetic radiation   sant is a quartz halogenated tungsten filament lamp, a xenon arc lamp or a xenon-mercury arc lamp, 6 -A device according to claim 1r characterized   in that the source of non-ionic electromagnetic radiation sant is a light emitting diode, 7 - Apparatus according to claim 1 characterized   in this cue the source of non-ionic electromagnetic radiation   sant is a tunable laser beam. 8 - Apparatus according to claim 1, characterized   in that wavelength selection means are pre-   seen between the source of electromagnetic radiation and the   biological material under exploration. 9 - Apparatus according to claim 8, characterized in that the means for choosing the wavelength comprises   at least two thin film passband optical filters, Apparatus according to claim 8P characterized   in that the wavelength choice mQyens include   at least one monochromator, 11 - Apparatus according to claim 9, characterized in that said filters include interface filters   wide band and thin film rence with peaks between about 450 and 1350 nm with intervals 50 nm.   12 - Apparatus according to claim 9, characterized in that the filters are mounted on a rotating wheel o10 placed adjacent to the source of electrical radiation   tromagnetic. 13 - Apparatus according to claim 1, characterized   in that radiation transmission means are pre-   seen to transmit electromagnetic radiation through firing from said source along a predetermined path to biological material, 14 - apparatus according to claim 13 <characterized   in that the means for transmitting radiation comprises   a flexible bundle of optical fibers.   15 - Apparatus according to claim 13, characterized   in that the means for transmitting radiation comprises a rigid light guide pipe, 16 - apparatus according to claim 1, characterized   in that the detection means comprise means of information photon terception. 17 - Apparatus according to claim 16, characterized in that the means for intercepting photons comprises a silicon or germanium photodiode or a row of silicon or germanium photodiodes.   18 - Apparatus according to claim 11 characterized in that the detection means comprise a photoQ 'multiplier tube. 19 - Apparatus according to claim 1, characterized in that the detection means comprise a television camera capable of detecting infrared light, - Apparatus according to claim 19, characterized in that an electronic television camera is used in colors as a means of detection. 21 - Apparatus according to claim 1, characterized in that the detection means comprise means   storage on video discs or computer discs.   22 - Apparatus according to claim 1, characterized   in that the detection means comprise an emma tube waste of images. 23 - Apparatus according to claim 1, characterized in that the detection means comprise axial tomography means with adjustment by computer to establish   a tomographic image of the biological material explored.   24 - Apparatus according to claim 1, characterized in that the biological material to be explored is placed between the source of the electromagnetic radiation and the means of detection and in that the source of electromagnetic radiation   genetic, and the detection means are moved by mo-   straight yen for exploration in relation to the material in exploration course.   - Apparatus for exploring living human tissue, characterized in that it comprises a light source capable   to emit visible light having a wavelength of   about 400 to 700 µm or infrared light with a wavelength of about 700 to 1 x 106 nim; wavelength selection means by which light from the source can be selectively sent, means emitting light having a light entry facet in position   adjacent to the means for choosing the wavelength and a fac-   this light output adjacent to the human tissue   hand subjected to exploration, and light detection means on the side of this tissue opposite to that on which is mounted the light exit facet of the light emitting means. 26 - Apparatus according to claim 25, characterized in that the light detection means are mounted on the same side of the fabric as that comprising the exit facet   light emitting light-.   27 - Apparatus according to claim 25, characterized in that the light source is a halogenated tungsten filament lamp, a xenon arc lamp or a xenon and mercury arc lamp: e 28 Apparatus according to claim 25, characterized in that the human tissue is a ferment breast, 29 - The apparatus according to claim 25, characterized in that the means for choosing the wavelength comprises   at least two optical bandpass filters. - Apparatus according to claim 25, characterized in that the means for choosing the wavelength comprises   at least one monochromator, 31 - Apparatus according to claim 25, characterized   in that the light emitting means comprise a beam flexible fiber optic skin.   32 - Apparatus according to claim 25, characterized in that the light emitting means comprise a   rigid light guide pipe. 33 - Apparatus according to claim 25, characterized in that the light detection means comprise a   silicon or germanium photodiode or such a beam photodiodes. 34 - Apparatus according to claim 25, characterized in that the light detection means comprise   an infrared lead sulfide vidicon. - Apparatus according to claim 25, characterized in that the light detection means comprise   a video disc, computer disc, or storage tube sinage of images.   36 - Apparatus according to claim 25, characterized in that the light detection means comprise a photomultiplier tube. 37 - Apparatus according to claim 25, characterized in that means for amplifying signals are provided for the light detection means. 38 - Apparatus according to claim 25, characterized in that signal display means are provided for the light detection means, 39 - Apparatus according to claim 38, characterized in that the signal display means are associated at rectilinear means of exploration.   -Apparatus according to 1l reyendication 38f characterized in that the signal display means are associated with means of axial topographic images with adjustment by computer, 41 - Apparatus for detecting and locating lesions of the chest and more particularly of the breast of a human being, characterized in that it comprises a source of   light capable of emitting visible light having a long   wavelength of about 400 to 700 nm or infrared light   red having a wavelength of about 700 to 1400 nm; a rotating wheel carrying a series of interference filters wide band and thin film rence whose peaks are between 450 and 1350 nm with intervals of about 50 nm, this wheel being positioned relative to the light source so as to allow any of the filters of the wheel intercepting the light emitted by said source;   a flexible bundle of optical fibers having a facet of   a light port for receiving light passing through said selected filter and a light exit facet for transmitting filtered light from the source to a breast suspected of being injured; adjustable means making contact with the chest, said means comprising aligned light direction means and light collecting means and light detecting means in conjunction with the light collecting means to provide an indication of the difference between light absorption and scattering characteristics   Light in the area of the chest through which the lumens pass 42 Apparatus according to claim 41, characterized in that the light detection means comprise a variable aperture photodetector, independent detectors   concentrically arranged dants or a network of detectors, 43 - Apparatus as claimed in claim 41 characterized in that the light source is a quartz halogenated tungsten filament lamp, a xenon arc lamp or a xenon and mercury arc lamp , 44 - Apparatus according to claim 41, characterized in that the light collecting means comprise a 24 2481454 silicon or germanium photodiode.   - Apparatus according to claim 41, characterized in that the light detection means comprise a digital reading unit with digital photometer comprising a liquid crystal display. 46 Apparatus according to claim 41, characterized in that the light detection means comprise a   photomultiplier tube or television camera tube.   47 - Apparatus according to claim 41, characterized in that the light detection means are coupled to a graphical recorder making it possible to establish a permanent plot of the absorption and diffusion characteristics breast tissue.