WO2022240007A1

WO2022240007A1 - Free-scanning pen-type optoacoustic tomography sensing system for measurement of melanin in skin

Info

Publication number: WO2022240007A1
Application number: PCT/KR2022/005870
Authority: WO
Inventors: 전만식; 성대운; 이재율; 김지현; 한상엽
Original assignee: 경북대학교 산학협력단
Priority date: 2021-05-11
Filing date: 2022-04-25
Publication date: 2022-11-17
Also published as: KR20220153408A; KR102542585B1; KR102542585B9

Abstract

An optoacoustic tomography sensing system comprises: a light source unit which generates laser; a pen-type probe which is optically coupled to the light source unit to irradiate the laser and to obtain an optoacoustic signal; and a signal obtainment unit which amplifies the obtained optoacoustic signal and obtains data. By providing a pen-type optoacoustic tomography sensing system capable of transmitting laser deeper than the depth that can be measured by using scattering-based imaging equipment of the related art, navigation information in the depth direction of a cell nevus may be obtained, and by using the pen-type probe, free scanning may be possible regardless of the location of an object to be measured.

Description

Free scanning pen-type photoacoustic tomographic sensing system for measuring melanin in the skin

The present invention relates to a free scanning pen-type optoacoustic tomographic sensing system for measuring intradermal melanin, and more particularly, to a free scanning pen-type optoacoustic tomographic sensing system for non-invasively measuring intradermal melanin.

Pigmented lesions appearing on the skin include various forms such as dots, freckles, blemishes, black spots, age spots, and nevus of Ota. In general, these pigmented lesions are caused by excessive production of melanin pigment due to exposure to ultraviolet rays for a long time or by aggregation of nevus cells producing melanin pigment.

In order to remove lesions in terms of medicine or skin care, information on the depth of the melanocyte nevus or the density of melanocytes is required in advance.

However, as a method of measuring the melanin component present in the epidermis and dermis from the surface of the conventional measured skin, there is a method of determining the color of the skin through a visual inspection or microscope, and, if necessary, analyzing the component through a biopsy. . In particular, the most representative method is a non-invasive method, which is measured using scattering-based imaging equipment. However, scattering-based imaging equipment has a problem in that it is difficult to accurately measure because the measurable depth is shallow and the depth direction of the melanocyte nevus is unknown.

[Prior art literature]

[Patent Literature]

(Patent Document 1) Republic of Korea Patent Publication No. 10-2014-0001453

The present invention has been made to solve the above problems, and an object of the present invention is a pen capable of obtaining depth direction navigation information of a cell nevus by penetrating a laser deeper than the depth measurable by conventional scattering-based imaging equipment. It is to provide a type photoacoustic tomography sensing system.

Another object of the present invention is to provide a pen-type photoacoustic tomographic sensing system capable of measuring the depth-direction formation of melanoma or efficiently distinguishing borderline, complex, and intradermal nevus according to the location of melanocyte nevus in skin tissue. is to provide

Another object of the present invention is to improve the precision and efficiency of evaluation by being used for diagnosis and postoperative evaluation of skin diseases such as malignant melanoma or for diagnosis and evaluation before and after point removal surgery. It is to provide a pen-type photoacoustic tomographic sensing system.

An optoacoustic tomography sensing system according to an embodiment of the present invention for achieving the above object includes a light source unit generating a laser; a pen-type probe that is optically coupled to a light source unit to irradiate the laser beam and obtain an optoacoustic signal; and a signal acquisition unit for amplifying the obtained optoacoustic signal and acquiring data.

Here, the pen-type probe includes a collimator that converts the laser into parallel light; An axicon lens that generates a Bessel beam by receiving parallel light; and an acoustic lens, and may include an ultrasonic transducer positioned at a rear end of the axicon lens to obtain an optoacoustic signal.

The pen-type probe may further include a donut lens that allows the Bessel beam to pass through and be focused on a specific region or point, and to match an axis of the focused Bessel beam with an axis of a direction in which the optoacoustic signal is obtained. .

In addition, the pen-type probe may be provided such that central axes of the collimator, the axicon lens, the ultrasonic transducer, and the donut lens are all positioned on the same line.

In addition, a hole having a predetermined size may be formed in the center of the donut lens, and the ultrasonic transducer may be inserted into the hole and positioned around the ultrasonic transducer.

In addition, one surface of the donut lens may be formed as a flat surface and the other surface may be formed to have a parabolic surface by a predetermined curvature, and the parabolic surface may be provided to face the axicon lens.

The signal acquisition unit may include an amplification module that amplifies the acquired optoacoustic signal; a digitizer acquiring data corresponding to the amplified photoacoustic signal; and a display outputting the acquired data.

According to one aspect of the present invention described above, by providing a pen-type optoacoustic tomography sensing system capable of penetrating a laser deeper than a measurable depth with conventional scattering-based imaging equipment, it is possible to obtain depth direction navigation information of a cell nevus. It can be used for diagnosis and postoperative evaluation of skin diseases such as malignant melanoma, or for diagnosis and evaluation before and after mole removal surgery to improve the precision and efficiency of evaluation.

In addition, it is possible to measure the degree of formation of melanoma in the depth direction or to efficiently distinguish border nevus, compound nevus, and intradermal nevus according to the location of the melanocyte nevus in the skin tissue.

Furthermore, this pen-type photoacoustic tomography sensing system may be used to acquire bio signals such as changes in oxygen saturation at a single point by utilizing multiple wavelengths.

1 is a diagram for explaining the configuration of a pen-type optoacoustic tomography sensing system according to an embodiment of the present invention;

2 is a view for explaining the combination of an ultrasonic transducer and a donut lens according to an embodiment of the present invention, and,

FIG. 3 is a diagram for explaining how a laser is transmitted and an optoacoustic signal is acquired in a pen-type probe according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The detailed description of the present invention which follows refers to the accompanying drawings which illustrate, by way of illustration, specific embodiments in which the present invention may be practiced. These embodiments are described in sufficient detail to enable one skilled in the art to practice the present invention. It should be understood that the various embodiments of the present invention are different from each other but are not necessarily mutually exclusive. For example, specific shapes, structures, and characteristics described herein may be implemented in another embodiment without departing from the spirit and scope of the invention in connection with one embodiment. Additionally, it should be understood that the location or arrangement of individual components within each disclosed embodiment may be changed without departing from the spirit and scope of the invention. Accordingly, the detailed description set forth below is not to be taken in a limiting sense, and the scope of the present invention, if properly described, is limited only by the appended claims, along with all equivalents as claimed by those claims. Like reference numbers in the drawings indicate the same or similar function throughout the various aspects.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings.

1 is a view for explaining the configuration of a pen-type optoacoustic tomography sensing system according to an embodiment of the present invention, and FIG. 2 is a combination of an ultrasonic transducer 230 and a donut lens 250 according to an embodiment of the present invention. , and FIG. 3 is a diagram for explaining how a laser is transmitted and an optoacoustic signal is obtained in the pen-type probe 200 according to an embodiment of the present invention.

The pen-type photoacoustic tomographic sensing system according to the present embodiment measures and evaluates the melanin component present in the surface and dermis of the skin, and in order to effectively and conveniently measure various components such as blood, the light source unit 100, the pen It includes a pen-type probe 200 and a signal acquisition unit 300.

The light source unit 100 is for transmitting the laser generated through optical coupling with the pen-type probe 200 to generate laser, and includes a laser source 110 and a collimator 120.

The light source unit 100 may generate single-wavelength, multi-wavelength, or wavelength-tunable pulse lasers, and various laser sources such as semiconductor lasers, light emitting diodes, solid-state lasers, or gas lasers that generate specific wavelength components or monochromatic light containing the components ( 110), as well as a plurality of laser sources 110 having different wavelengths.

More specifically, the light source unit 100 according to this embodiment generates a wavelength of 700 nm band when measuring the melanin component in order to take advantage of the fact that different biological tissues have various absorbances according to the wavelength of light, and blood vessels When measuring the back, it may include a laser source 110 capable of generating a wavelength in the 500 nm band.

The collimator 120 included in the light source unit 100 is provided for optical coupling with the pen-type probe 200, and the collimator 120 of the light source unit 100 is connected to the collimator 210 of the pen-type probe 200. do. Through this, the laser generated from the laser source 110 is transmitted to the collimator 210 of the pen type probe 200 .

Therefore, the light source unit 100 according to the present embodiment is connected to the pen-type probe 200 through the collimator 120 forming a parallel beam of light through an optical fiber.

Meanwhile, the pen-type probe 200 according to the present embodiment receives the laser generated from the light source unit 100 through light coupling with the light source unit 100, irradiates it to a target to be photographed, and acquires an optoacoustic signal output from the target to be photographed. And the acquired optoacoustic signal may be transmitted to the signal acquisition unit 300 .

The pen-type probe 200 is configured and arranged according to an optical design that converts laser from an optical fiber into small-diameter collimated light and then generates a Bessel beam to perform line focusing or area focusing on a target area. For this purpose, the pen-type probe 200 in the present invention includes a collimator 210, an axicon lens 220, an ultrasonic transducer 230, an acoustic lens 240, and a donut lens 250. arranged to do

The collimator 210 converts the laser into small-aperture collimated light and irradiates it toward the axicon lens 220 .

Meanwhile, the axicon lens 220 generates a Bessel beam from parallel light and irradiates the Bessel beam toward an object to be photographed. As shown in FIG. 1 , such a Bessel beam travels along a certain path toward an object to be photographed.

The ultrasonic transducer 230 is located at the rear end of the axicon lens 220 based on the traveling direction of the laser, obtains an optoacoustic signal based on ultrasonic waves emitted from a subject to be photographed, and transmits the obtained optoacoustic signal to a signal acquisition unit. forwarded to (300). In addition, an acoustic lens 240 is provided at one end of the ultrasonic transducer 230, and the acoustic lens 240 collects ultrasonic waves emitted from a subject to be photographed and transmits them to the ultrasonic transducer 230.

When the electromagnetic pulse of the laser is incident on a biological tissue such as the skin, a portion of the energy is absorbed by the light absorbing material in the tissue and converted into heat, causing thermoelastic expansion, and as a result, ultrasonic waves having a wide band of frequencies are emitted, resulting in the emitted Ultrasound is acquired as an optoacoustic signal in the ultrasonic transducer 230 .

The donut lens 250 is provided to increase the Sigmal to noise ratio (SNR) while enabling the optoacoustic tomography sensing system according to the present embodiment to have a deeper imaging depth. To this end, the Bessel beam generated from the axicon lens 220 is passed through and focused on a specific area or point passing through, and when the Bessel beam is irradiated toward a photographing target, the axis of the focused Bessel beam and the acoustic lens 240 The axis of the acquisition path of the photoacoustic signal obtained from the photographed object to be collected may be matched.

In addition, the donut lens 250 according to the present embodiment has a hole having a predetermined size in the center, and the ultrasonic transducer 230 is inserted into the hole so that the ultrasonic transducer 230 is positioned around the ultrasonic transducer 230 . As shown in FIG. 2, one surface of the donut lens 250 is formed as a flat surface, and the other surface is formed as a plano-convex lens having a predetermined curvature. At this time, the donut lens 250 has a diameter of 25.4 cm and a center thickness of 25.4 cm. may be selected within 12 cm to 18 cm, and the diameter of the hole may be provided as 12 cm. Of course, this may be changed in consideration of the external diameter and focal length of the inserted ultrasonic transducer 230 as an example for convenience of description.

The Bessel beam passing through the donut lens 250 is converged at a certain point, and as shown in FIG. 3, the axis of the Bessel area and the axis of the path for obtaining the photoacoustic signal coincide The pen-type probe 200 according to the example enables deep sensing as well as increasing a signal-to-noise ratio.

Therefore, as shown in FIG. 3, the optoacoustic tomographic sensing system viewed through the donut lens 250 according to the present embodiment is 3 to 5 mm from the skin surface compared to the imaging depth (~1 mm) of conventional scattering-based image imaging equipment. Since it has an imaging depth of up to, it is possible to measure areas deep below the skin surface.

In addition, in the pen-type probe 200 according to this embodiment, the central axes of the collimator 210, the axicon lens 220, the ultrasonic transducer 230, the acoustic lens 240, and the donut lens 250 are all on the same line. , it can be provided in the form of a probe for a handle of a fiber-based pen type, thereby providing a user-friendly and easily usable optoacoustic tomography sensing system through free scanning.

Meanwhile, the signal acquisition unit 300 is provided to amplify the photoacoustic signal obtained from the pen-type probe 200 and acquire data, and includes the amplification module 310, the digitizer 320, and the display 330. can include

The amplification module 310 receives and amplifies the optoacoustic signal obtained from the ultrasonic transducer 230 .

The digitizer 320 acquires data corresponding to the amplified optoacoustic signal.

The display 330 outputs the data acquired by the digitizer 320 as an image.

Although various embodiments of the present invention have been shown and described above, the present invention is not limited to the specific embodiments described above, and is commonly used in the technical field to which the present invention pertains without departing from the gist of the present invention claimed in the claims. Of course, various modifications are possible by those with knowledge of, and these modifications should not be individually understood from the technical spirit or prospect of the present invention.

[Description of code]

100: light source unit 110: laser source

120: collimator 200: pen type probe

210: collimator 220: axicon lens

230: ultrasonic transducer 240: acoustic lens

250: donut lens 300: signal acquisition unit

310: amplification module 320: digitizer

330: display

Claims

a light source unit generating a laser;

a pen-type probe that is optically coupled to a light source unit to irradiate the laser beam and obtain an optoacoustic signal; and

An optoacoustic tomography sensing system comprising a signal acquisition unit that amplifies an acquired optoacoustic signal and acquires data.
According to claim 1,

The pen-type probe,

a collimator that converts the laser into collimated light;

An axicon lens that generates a Bessel beam by receiving parallel light; and

An optoacoustic tomography sensing system comprising an acoustic lens and an ultrasonic transducer positioned at a rear end of the axicon lens to acquire an optoacoustic signal.
According to claim 2,

The pen type probe,

Optoacoustic tomography sensing characterized by further comprising a donut lens for passing the Bessel beam and focusing it on a specific area or point, and matching an axis of the focused Bessel beam with an axis of a direction in which the optoacoustic signal is obtained. system.
According to claim 3,

The pen type probe,

The optoacoustic tomographic sensing system, characterized in that the central axes of the collimator, the axicon lens, the ultrasonic transducer, and the donut lens are all positioned on the same line.
According to claim 3,

The donut lens,

A hole having a predetermined size is formed in the center, and the ultrasonic transducer is inserted into the hole and positioned around the ultrasonic transducer.
According to claim 3,

The donut lens,

An optoacoustic tomography sensing system, characterized in that one surface is formed as a plane and the other surface is formed to have a parabolic surface by a predetermined curvature, and the parabolic surface is provided to face the axicon lens.
According to claim 1,

The signal acquisition unit,

an amplification module for amplifying the acquired optoacoustic signal;

a digitizer acquiring data corresponding to the amplified photoacoustic signal; and

Characterized in that it comprises a display for outputting the obtained data, the optoacoustic tomography sensing system.