WO2009144623A1

WO2009144623A1 - Control of measurement and/or treatment means of a probe

Info

Publication number: WO2009144623A1
Application number: PCT/IB2009/052094
Authority: WO
Inventors: Yan Liu; Bastiaan W. M. Moeskops; Golo Von Basum; Kiran K. Thumma
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2008-05-26
Filing date: 2009-05-20
Publication date: 2009-12-03

Abstract

The present invention provides a system (110) for controlling measurement and/or treatment means of a probe (10). The system (110) comprises a probe (10) with an outwardly curved probe head (11) having a contact surface (12) adapted for contacting skin (13) of a human or animal body. A plurality of pressure sensors (23) is distributed over the contact surface (12), the plurality of pressure sensors (23) being for obtaining a feedback signal indicative of locations where contact exists between the probe (10) and skin (13) of the human or animal body, also referred to as target locations. The system (110) furthermore comprises a controller (17) for selectively driving measurement and/or treatment means located at the target location based on the feedback signal from the pressure sensors (23). The present invention also provides a method for making a system (110) for controlling measurement and/or treatment means of a probe (10) and a method for controlling measurement and/or treatment means of a probe (10).

Description

Control of measurement and/or treatment means of a probe

TECHNICAL FIELD OF THE INVENTION

The present invention relates to measurement and/or treatment probes. More particularly the present invention relates to a system for controlling measurement and/or treatment means of a probe, to a method for making such a system and to a method for controlling measurement and/or treatment means of a probe.

BACKGROUND OF THE INVENTION

Obtaining values for biological or physical quantities in a living body in a noninvasive way has been thoroughly studied over the last decades. Obtaining accurately reproducible results by using sophisticated sensing and actuating devices for medical purposes may become difficult when sensors have to be repeatedly removed and replaced.

Currently, many efforts have been put in developing instruments for noninvasive measurement of physiological parameters in a human or animal body, such as for example glucose measurements, based on optical methods. Although these methods are proven to have sufficient sensitivity for in- vitro and/or ex- vivo glucose quantification, devices based on such currently existing techniques has been successfully brought to the market. The main reason for that is that the accuracy of recently developed devices is not sufficient to get an FDA (food and drug administration) approval.

Non-invasive measurement is the most desirable method for consumers. But the uncertainty and inaccuracy hampers the acceptance of non- invasive tests. There is a strong need in the non-invasive glucose-monitoring market to solve the inaccuracy or unreliability problems.

It has been found that various interfering elements, such as e.g. humidity, temperature, perfusion rate etc., affect the results of such non- invasive measurements. Additionally, the skin- interface plays a big role during performance of the non- invasive measurements. Therefore, in known techniques the shape of probe may be adapted so as to ensure contact of the probed with the skin. For example, US 5,906,580 relates to a probe having a shape suitable for fitting different application sites. This document mentions that the size and shape of a probe of an ultrasound system may depend on its intended application. For example, when the probe is intended for use in non- invasive scanning of a surface of a body, the probe may have a flexible face that conforms to specific parts of the body as it is moved across such specific parts.

Many techniques have been investigated to non-invasively detect skin analyze(s) concentration by means of optical, electrical and/or optoelectronic methods, such as for example non-invasive glucose monitoring. Typically, in vivo measurements deal with a larger number of chemical, physical, and physiological interfering elements compared to in vitro measurements. These interfering elements induce ^reproducibility and inaccuracy of non- invasive measurements. Moreover, things like skin- interface, shape and angle of the probe applied to the measuring site, may influence the accuracy of the measurement.

Conventional probe heads (see Fig. 1) have a flat surface 1, which requires a perpendicular orientation of the probe 2 onto the skin 3 to achieve a close contact with the skin 3. However, it may be difficult to precisely control the angle CC of the probe 2 during non- invasive measurement, especially when hand-handling the probe 2. The angle CC may be varied from measurement to measurement (i.e. in time), from person to person and from measurement site to measurement site.

US 5,588,440 describes a probe for contacting a desired area of skin for assessing and for locating soft tissue lesions manifested by pain in the tissue of human beings and animals (see Fig. 2). The probe has a rounded tip which has an opening through which there protrudes three sensors 4, 5, 9, one for measuring moisture content, one for measuring temperature and one for measuring applied force. An open area 6 around the sensors serves to conduct sound produced during massage of the skin at that area up to a sound detector or stethoscope. However, problems with respect to the contact between the measurement part of the probe and the skin can arise with this probe when, for particular reasons, measurements have to be performed by placing the probe under an angle with respect to the skin.

SUMMARY OF THE INVENTION

It is an object of embodiments of the present invention to provide a good system for controlling measurement and/or treatment means of a probe, to a method for making such a system and to a method for controlling measurement and/or treatment means of a probe.

The system and the methods according to embodiments of the invention have a good efficiency and accuracy. The system and the methods according to embodiments of the invention may be may be used with any technique for sensing analyses within the skin or within a body fluid of a human or animal body, such as e.g. non- invasive glucose detection. The system and the methods according to embodiments of the invention may furthermore be used for measuring skin properties such as e.g. skin cancer, skin aging.

The above objective is accomplished by a method and device according to the present invention.

In a first aspect, the present invention provides a system for controlling measurement and/or treatment means of a probe. The system comprises: a probe with an outwardly curved, e.g. convex, probe head having a contact surface adapted for contacting skin of a human or animal body, a plurality of pressure sensors distributed over the contact surface, the plurality of pressure sensors being for obtaining a feedback signal indicative of target locations where contact exists between the probe and skin of the human or animal body, and a controller adapted for selectively driving measurement and/or treatment means located at the target location based on the feedback signal from the pressure sensors.

With "an outwardly curved probe head" is meant a probe head having an outwardly curved shape such as, for example, a rounded shape, oval shape or egg shape. In embodiments of the present invention, the probe head may be convex. The contact surface of the probe head is defined as a surface of the probe head which may contact the skin of a human or animal body during performance of measurement of the physiological parameter in and/or treatment of a human or animal body.

A system according to embodiments of the invention shows a good efficiency and accuracy. A system according to embodiments of the invention may be used with any technique for sensing analyses within the skin or within a body fluid of a human or animal body. A system according to embodiments of the invention may be used for, for example, non- invasive glucose detection by means of optical spectroscopy. Further techniques with which a system according to embodiments of the invention may be used may include measurements of skin properties such as e.g. skin cancer, skin aging by any means of radiation, e.g. light.

The system may furthermore comprise a plurality of measurement and/or treatment means distributed over the contact surface of the probe head. A system according to these embodiments of the invention may, for example, be used to determine the presence and/or concentration of an analyze in a body fluid such as e.g. blood or interstitial fluid (also referred to as tissue fluid or intercellular fluid), or within the skin of a human or animal body. According to embodiments of the invention, the measurement and/or treatment means may comprise illumination means.

According to further embodiments of the invention, the measurement and/or treatment means may furthermore comprise measurement elements, such as e.g. optical, ultrasound, photo acoustic measurement elements. According to embodiments of the invention, the illumination means may comprise a plurality of optical fibres of which ends are distributed in the probe head.

According to other embodiments of the invention, the illumination means may comprise a radiation source for generating a radiation bundle in a light guide and a shield comprising multi-switches which can separately and selectively be driven. The probe may furthermore comprise a memory for storing a value representative of the feedback signal. In the memory the signals received from the pressure sensors may be stored. The memory may also comprise an algorithm so as to determine which measurement means have to be activated starting from the signals coming from the pressure sensors. According to embodiments of the invention, the probe may be a probe for measuring a physiological parameter of the human or animal body.

In a second aspect, the invention provides the use of a system according to embodiments of the invention for non- invasive glucose monitoring.

Furthermore, a system according to embodiments of the invention may also be applicable for performing a treatment, such as heat or light treatment for hair removal, treatment of skin disorders by e.g. light, or skin rejuvenation.

The present invention also provides the use of a system according to embodiments of the invention for determining skin properties such as e.g. skin cancer or skin aging. In a further aspect, the invention provides a method for making a system for controlling measurement and/or treatment means of a probe. The method comprises: providing a probe with an outwardly curved, e.g. convex, probe head having a contact surface adapted for contacting skin of a human or animal body, providing a plurality of pressure sensors distributed over the contact surface, the plurality of pressure sensors being adapted for obtaining a feedback signal indicative of locations where contact exists between the probe and skin of the human or animal body, and providing a controller adapted for selectively driving measurement and/or treatment means based on the feedback signal from the pressure sensors.

The method may furthermore comprise providing measurement and/or treatment means distributed over the contact surface of the probe head.

Providing measurement and/or treatment means may comprise providing illumination means. According to embodiments of the invention, providing measurement and/or treatment means may furthermore comprise providing measurement elements such as e.g. optical, ultrasound, photo acoustic measurement elements.

According to embodiments of the invention, providing illumination means may be performed by providing a plurality of optical fibres of which ends are distributed in the probe head.

According to other embodiments of the invention, providing illumination means may be performed by providing a radiation source for generating a radiation bundle in a light guide and a shield comprising multi- switches which can be driven separately and selectively. The present invention also provides a system for controlling measurement and/or treatment means of a probe made by a method according to embodiments of the invention.

In a further aspect, the present invention provides a method for controlling measurement and/or treatment means of a probe. The method comprises: measuring pressure for detecting target locations where contact is made between the probe and skin of the human or animal body, thereby generating a feedback signal indicative of such target locations, and selectively driving the measurement and/or treatment means based on the feedback signal so as to selectively activate those measurement and/or treatment means positioned at the detected target locations.

In another aspect, the present invention also provides a method for controlling measurement means of a probe. The method comprises measuring pressure for detecting target locations where contact is made between the probe and skin of the human or animal body, thereby generating a feedback signal indicative of such target locations, and selectively driving the measurement means based on the feedback signal so as to selectively activate those measurement means positioned at the detected target locations.

According to embodiments of the invention, the method may furthermore comprise non-invasively measuring a physiological parameter of the human or animal body.

According to further embodiments, the method may furthermore comprise performing a treatment on the human or animal body. Detecting target locations may be performed by determining whether a force not smaller than a predetermined force, e.g. a force of at least 5 g/cm² or at least 10 g/cm², is applied by the probe to the skin during at least a predetermined time period, e.g. a time period of longer than 1 sec, a time period of longer than 0.1 sec, a time period of longer than 2 sec, for example longer than 4 sec. According to embodiments of the invention, the measurement and/or treatment means may comprise a plurality of optical fibres and a plurality of measurement elements and selectively activating the measurement and/or treatment means may be performed by activating at least part of the optical fibres and at least part of the measurement elements. According to other embodiments of the invention, the measurement and/or treatment means may comprise a radiation source for generating a radiation bundle in a light guide, a shield comprising multi- switches and a plurality of measurement elements and selectively activating the measurement and/or treatment means may be performed by activating the multi-switches of the shield such that at least part of the multi- switches open for allowing the radiation to get through the shield. The method may furthermore comprise storing a value representative of the feedback signal in a memory, in other words, storing locations of contact in a memory based on signals coming from the pressure sensors.

The skin may lie in a plane and controlling measurement and/or treatment means of a probe may be performed by providing the probe such that it makes an angle of between 0° and 90° with a direction substantially perpendicular to the plane of the skin and the method may furthermore comprise changing the angle of the probe with respect to the direction substantially perpendicular to the plane of the skin and repeating the pressure measuring and selectively driving steps. In a further aspect, the present invention provides a controller for controlled driving of a measurement and/or treatment means of a probe. The controller comprises a control unit for selectively activating measurement and/or treatment means in accordance with a feedback signal indicative of target locations where contact exists between the probe and skin of the human or animal body.

The controller may furthermore comprise a memory for storing a value representative of the feedback signal based on signals coming from the pressure sensors.

The present invention also provides a computer program product for performing, when executed on a computing means, a method according to embodiments of the invention.

The present invention also provides a machine readable data storage device storing the computer program product according to embodiments of the invention.

The present invention also provides transmission of the computer program products according to embodiments of the invention over a local or wide area telecommunications network.

Particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. Features from the dependent claims may be combined with features of the independent claims and with features of other dependent claims as appropriate and not merely as explicitly set out in the claims. The above and other characteristics, features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. This description is given for the sake of example only, without limiting the scope of the invention. The reference figures quoted below refer to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 and Fig. 2 show known measurement probes.

Fig. 3 illustrates a system according to embodiments of the invention.

Fig. 4 and Fig. 5 illustrate probes to be used with a system according to embodiments of the present invention.

Fig. 6 shows an example of an algorithm to be used with a method according to embodiments of the present invention.

Fig. 7 schematically illustrates more details of a system controller for use with a system according to embodiments of the present invention. Fig. 8 is a schematic representation of a processing system as can be used for performing a method according to embodiments of the present invention.

In the different figures, the same reference signs refer to the same or analogous elements.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims. Any reference signs in the claims shall not be construed as limiting the scope. The drawings described are only schematic and are non- limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes.

Where the term "comprising" is used in the present description and claims, it does not exclude other elements or steps. Where an indefinite or definite article is used when referring to a singular noun e.g. "a" or "an", "the", this includes a plural of that noun unless something else is specifically stated.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments. Similarly it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

Furthermore, some of the embodiments are described herein as a method or combination of elements of a method that can be implemented by a processor of a computer system or by other means of carrying out the function. Thus, a processor with the necessary instructions for carrying out such a method or element of a method forms a means for carrying out the method or element of a method. Furthermore, an element described herein of an apparatus embodiment is an example of a means for carrying out the function performed by the element for the purpose of carrying out the invention.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

The present invention provides a system for controlling measurement and/or treatment means of a probe, a method for making such a system and a method for controlling measurement and/or treatment means of a probe. According to embodiments of the invention, the system may be for measuring a value of a physiological parameter in a human or animal body.

The physiological parameter may, for example, be any physiological parameter present in a body fluid such as blood or an interstitial fluid (also referred to as tissue fluid or intercellular fluid) and of which it is important to detect its presence and/or to determine its concentration. An example hereof is the concentration of glucose in the blood of a human being. The analyte can be any organic molecule which is present in a human or animal body such as, for example, glucose, cholesterol, haemoglobin, acetone, water, fat, keratin, lactic acid or melanin, or can be any inorganic molecule in a human or animal body such as, for example, iron or calcium, or can be another feature such as, for example the presence and/or concentration of gases or pH.

A system according to embodiments of the present invention may be generally used with any sensing method or treatment method, or a combination of both, which benefit from a good contact between a contact surface of the probe and skin of the human or animal body. Examples of such sensing methods may, for example, be ultrasound, temperature sensing, pressure sensing, measurements using parts of the electromagnetic spectrum (such as optical, microwave or radio wave methods), skin impedance and capacitance measurements, and measurements of flux of compounds (such as TransEpidermal Water Loss). Examples of treatment methods may, for example, be any treatment method to be applied to skin of a human or animal body, such as heat or light for hair removal, treatments for skin disorder or skin aging, any treatment method to be applied through skin of a human or animal body, such as medication injection or transdermal drug delivery, treatment of skin disorders by e.g. light, skin rejuvenation or any method to be applied into skin, such as using catheter ablation or taking biopsy. According to other embodiments of the invention, the physiological parameter may also be a parameter suitable for determining skin properties such as e.g. skin cancer or skin aging. In such cases, the parameter may, for example, be reflectivity, evenness, temperature, temperature difference, color, color differences, stains. As an example, parameters for determining skin properties such as skin cancer and skin aging could be optical properties of the skin. These may, among others, comprise performing measurements of absorption, scattering, reflection or birefringence at one or more wavelengths.

The system and methods according to embodiments of the invention show a good efficiency and accuracy.

The system and methods according to embodiments of the invention may, for example, be used to determine the presence and/or concentration of an analyte in a body fluid such as e.g. blood or interstitial fluid (also referred to as tissue fluid or intercellular fluid), or within the skin of a human or animal body. The analyte to be measured may, for example, be glucose, haemoglobin, water, fat, melanin or keratin. The system and methods according to embodiments of the invention may be used with any technique for measuring analytes within the skin or within a body fluid of a human or animal body. The system and methods according to embodiments of the invention may be used for, for example, non- invasive glucose detection by means of optical spectroscopy.

Further applications of the system and methods according to embodiments of the invention may include measurements of skin properties such as e.g. skin cancer, skin aging by any means of radiation, e.g. light.

As described above, parameters for determining skin cancer and skin aging may be optical properties of the skin. In a first aspect, the invention provides a system for controlling measurement and/or treatment means of a probe. The system comprises: a probe with an outwardly curved, e.g. convex, probe head having a contact surface adapted for contacting the human or animal body, a plurality of pressure sensors distributed over the contact surface, the plurality of pressure sensors being for obtaining a feedback signal indicative of target locations where contact exists between the probe and the skin of the human or animal body, and a controller adapted for selectively driving measurement and/or treatment means located at the target location in accordance with the feedback signal from the pressure sensors.

With "an outwardly curved probe head" is meant a probe head having an outwardly curved shape such as, for example, a rounded or circular shape, oval shape or egg shape. In embodiments of the present invention, the outwardly curved probe head may be a convex probe head. Fig. 3 shows a system 110 according to a first embodiment of the invention. In the example given, the system 110 comprises a probe 10 with an outwardly curved, for example convex e.g. rounded probe head 11 having an outwardly curved, e.g. rounded contact surface 12 adapted for contacting the human or animal body. The contact surface 12 of the probe head 11 is defined as a surface of the probe head 11 which may contact the skin 13 of a human or animal body during performance of measurement of the physiological parameter and/or treatment of the human or animal body. In embodiments of the present invention, the contact surface 12 is a smooth surface in order not to damage the skin. Into or onto the contact surface 12 a plurality of pressure sensors 23 (see Fig. 5) are provided adapted for detecting which part of the probe 10 touches the skin 13 when the probe 10 is provided to the skin 13 of the human or animal body. For certain applications it may be advantageous to obtain a value for the amount of pressure exerted by the probe 10 onto the skin 13. Therefore, optionally, the plurality of pressure sensors 23 may be for, at the same time as detecting which part of the probe 10 touches the skin 13, measuring the forces applied by the probe 10 to the skin 13. An output of the plurality of pressure sensors 23 may be a real (analogue) pressure value. A threshold value, that e.g. defines when skin contact has been reached, may be used to transform this to a digital yes/no value.

By determining which part of the probe 10 touches the skin 13, it may be determined which of the plurality of measurement and/or treatment means for respectively measuring a physiological parameter in and/or performing treatment of a human or animal body, have to be activated. Hence, the pressure sensors 23 provide a feedback to the measurement and/or treatment means so that the measurement and/or treatment means can efficiently be driven (see further), e.g. by only driving these measurement and/or treatment means which are in contact with a target location. The pressure sensors 23 may be randomly distributed over the contact surface 12. Alternatively, the pressure sensors 23 may be distributed over the contact surface 12 according to a regular or irregular array. According to embodiments of the invention, the probe 10 may comprise between 1 and 50, for example between 1 and 20 or between 2 and 5 pressure sensors 23, e.g. may comprise 2 or 3 pressure sensors 23. For example, a measuring area may be determined by using two pressure sensors 23 if these pressure sensors 23 are large enough compared to area of the measuring site or target location and thus when together they can cover the complete measuring site. In order to optimize, e.g. maximize, the sensitivity, a higher number of pressure sensors 23 may be used.

According to another example, the probe 10 may comprise three pressure sensors 23 placed in a ring around the center of the probe head 11, e.g. there being 120 degrees between neighboring pressure sensors 23 (see Fig. 5) and the orientation of the probe 10 may be calculated depending on the pressure measured by the pressure sensors 23. For example, if all pressure sensors 23 measure a same pressure, then probe 10 may be oriented perfectly vertically and one or more measurement and/or treatment means located at a tip of the probe 10 which are then in contact with the skin 13 may be selectively driven so as to be activated. If one pressure sensor 23, e.g. at a first side of the probe 10, measures a high pressure value, and the other two pressure sensors 23, e.g. at a tip and a second side different from the first side of the probe 10 measure equal low pressure values, then the probe 10 may be tilted in the direction of the pressure sensor 23 by which the high pressure value was measured and one or more measurement and/or treatment means located at that side, i.e. the first side of the probe 10 which is then in contact with the skin 13 may be selectively driven so as to be activated. Information obtained from the pressure sensors 23 may thus be used to estimate where the probe 10 must have good contact with the skin, even when no pressure sensor 23 is placed at that specific site. In this way, the number of pressure sensors 23 can be kept relatively low, allowing more space for measurement and/or treatment means. Alternatively, according to other embodiments, no reconstruction algorithm as described above is used, and the pressure sensors 23 are interspersed among the measurement and/or treatment means. This leads to a number of pressure sensors 23 which may then be similar to the number of measurement and/or treatment means. The measurement and/or treatment means for non-invasively measuring a physiological parameter, such as for example presence and/or concentration of an analyte in a body fluid (blood, interstitial fluid (also referred to as tissue fluid or intercellular fluid)) or within the skin of a human or an animal body and/or for performing treatment of the human or animal body may, according to embodiments of the invention, comprise illumination means. According to further embodiments of the invention, the measurement and/or treatment means may furthermore comprise measurement elements such as e.g. optical, ultrasound or photo acoustic measurement elements.

According to the example given in Fig. 3 the measurement and/or treatment means may comprise illumination means 14, 15 and corresponding optical detection elements 16. According to the present embodiment, the illumination means may comprise a number of optical fibres 14 of which the ends 15 are distributed in the probe head 11. The ends 15 of the optical fibres 14 may be randomly distributed. Alternatively, the ends 15 of the optical fibres 14 may be distributed over the contact surface 12 according to a regular or irregular array. According to embodiments of the present invention, the probe 10 may comprise between 1 and 100, for example between 1 and 50, between 1 and 20 or between 2 and 5 optical fibres 14.

The optical fibres, e.g. optical fibres which may be used as measurement means, may have diameters of between 50 μm and 1000 μm. Therefore, the distance between neighboring pressure sensors 23 may be such that such optical fibres may still be provided in between the pressure sensors 23. Hence, a minimum separation distance between neighboring pressure sensors 23 may be 50 μm. During practical mechanical design, this would mean that the pressure sensors 23 can be packed together with a thin wall separating them. Assuming an average optical fibre diameter of, for example, 200 μm, and a pressure sensor 23 diameter of ~ 2 mm, the size of the pressure sensors 23may be a limiting factor.

The results obtained by the pressure sensors 23 are used as a feedback signal for selectively driving the measurement and/or treatment means so as to activate the measurement and/or treatment means in contact with a target location for performing noninvasive measurements, such as e.g. glucose monitoring (see further), and/or for performing treatment on the human or animal body. Therefore, the system 110 furthermore comprises a controller 17 for selectively driving the measurement and/or treatment means located at the target location, in the example given some of the optical fibres 14 and some of the detection elements 16, determination of the measurement and/or treatment means located at the target location being based on the feedback signal from the pressure sensors 23. For example, if the skin 13 is lying in a plane, the probe 10 may be provided to the skin 13 thereby making an angle CC with a direction substantially perpendicular to the plane of the skin 13 so as to obtain a good contact between the contact surface 12 of the probe 10 and the skin 13. As can be seen from Fig. 3, in that case only part of contact surface 12 touches the skin 13. With the probe 10 according to embodiments of the present only those measurement and/or treatment means 14, 15 located in the neighborhood of the part of the contact surface 12 that touches the skin 13, i.e. the target location, are activated. In that way the probe 10 may be used efficiently and accurately as the measurement and/or treatment means which are too far away from the target location, and thus would not really contribute to the measurement and/or treatment, are not activated. This may lead to a longer lifetime of the probe 10, and thus of the system according to embodiments of the invention, because the measurement and/or treatment means are not used when not necessary. This may furthermore also lead to a longer battery life, for battery-operated devices.

The system 110 according to embodiments of the invention may be used such that the probe 10 makes an angle with respect to the skin 13. The probe 10 may make any angle α with respect to the skin surface, e.g. between 0° and 90°.

In that way, a best possible position may be obtained for obtaining a best possible contact between the probe 10 and the skin 13, as the skin 13 can show a lot of irregularities. In that way, accuracy of subsequent measurement of the physiological parameter and/or subsequent performance of the treatment may be improved.

Fig. 4 illustrates a probe 10 of a system 110 according to a second embodiment of the present invention. In this Figure, for the ease of explanation the controller 17 is not illustrated. The probe 10 of the system 110 according to this embodiment is similar to the probe 10 described in the first embodiment, in that it comprises an outwardly curved, for example convex, e.g. rounded probe head 11 having an outwardly curved contact surface 12, a plurality of pressure sensors 23 distributed over the contact surface 12, a measurement and/or treatment means and a controller 17 (not illustrated in Fig. 4).

The contact surface 12 of the probe head 11 is defined as the surface of the probe head 11 which may contact the skin 13 of a human or animal body during performance of measurement of the physiological parameter and/or treatment of the human or animal body. Into or onto the contact surface 12 a plurality of pressure sensors 23 are provided adapted for detecting which part of the probe 10 touches the skin 13 when the probe 10 is provided to the skin 13 of the human or animal body, and optionally for at the same time measuring the forces applied to the skin 13. The pressure sensors 23 may be randomly distributed over the contact surface 12. Alternatively, the pressure sensors 23 may be distributed over the contact surface 12 according to a regular or irregular array. As already described above, the pressure sensors 23 provide a feedback to the measurement and/or treatment means so that the measurement and/or treatment means can efficiently be driven. According to embodiments of the invention, the probe 10 may comprise between 1 and 50, for example between 1 and 20 or between 2 and 5 pressure sensors 23.

The measurement and/or treatment means may, according to the example given, comprise illumination means. According to the second embodiment, the illumination means may comprise a radiation source e.g. for providing a light bundle in a light guide 18. An end 19 of the light guide 18 may be located in the probe 10, e.g. in the centre of the probe 10 as is illustrated in Fig. 4. The radiation, e.g. light bundle, may be generated by a radiation source, e.g. light source (not shown in the figure). The radiation source, e.g. light source, may for example be a laser or a LED source. When, for example, using optical fibres to deliver the radiation, the radiation may be optical radiation, e.g. UV (ultraviolet), VIS (visual), IR (infrared). The measurement and/or treatment means may, according to the present embodiment, furthermore comprise a shield 20 comprising multi- switches to let a particular amount of radiation, e.g. light to get through the shield 20. The multi-switches (e.g. micro- mirrors, LCD-array, shutters, or any other known multi-switch) are controlled using input from the pressure sensors 23. The control algorithm then assigns a location as the measurement and/or treatment position, and opens corresponding shield element(s). This selected measurement and/or treatment position is then guaranteed to have good contact with the surface.

The amount and the location of radiation, e.g. light going through the shield 20 may be controlled by the controller 17 which uses a feedback signal generated by the plurality of pressure sensors 23. Hence, according to the second embodiment, the feedback signal obtained from the plurality of pressure sensors 23 is used for controlling the multi- switches of the measurement and/or treatment means. Optionally, when the measurement and/or treatment means also comprises detection elements 16, the controller 17 may also be used for controlling the detection elements 16. The pressure sensors 23 provide signals to the controller 17. The controller 17 derives, either via a reconstruction algorithm or via a simple algorithm depending on the ratio between the numbers of pressure sensors 23 vs. the number of optical fibres, an appropriate measurement and/or treatment location. The shield elements that would illuminate this location are then switched to an 'open' state. For example, if the skin 13 is lying in a plane, the probe 10 may be provided to the skin 13 thereby making an angle CC with a direction substantially perpendicular to the plane of the skin 13 so as to obtain a good contact between the contact surface 12 of the probe 10 and the skin 13. As can be seen from Fig. 4, in that case only part of contact surface 12 touches the skin 13. The contact area between the contact surface 12 of the probe 10 and the skin 13 is called the target location. With the system 110 according to embodiments of the present invention, only those measurement and/or treatment means located at the target location or in the neighborhood thereof are activated. In that way the probe 10 may be used efficiently and accurately as the measurement and/or treatment means which are too far away from the target location, and thus would not really contribute to the measurement and/or treatment, are not activated. This may lead to a longer lifetime of the probe 10, and thus of the system 110 according to embodiments of the invention, because the measurement and/or treatment means are not used when not necessary. It may also increase battery time.

The system 110 according to embodiments of the invention may be used such that the probe 10 makes an angle with respect to the skin 13. According to embodiments of the invention, the probe 10 may make any angle CC between 0° and 90°. In that way, a best possible position may be obtained for obtaining a best possible contact between the probe 10 and the skin 13, as the skin 13 can show a lot of irregularities.

An advantage of a system 110 according to embodiments of the invention is that the angle CC that the probe 10 makes with a direction substantially perpendicular to the plane of the skin 13 during the measurement and/or treatment does not affect measurement and/or treatment results because of the outwardly curved, for example convex, e.g. rounded probe head 11. Furthermore, because, upon receiving the feedback signal from the pressure sensors 23, the controller 17 decides which measurement and/or treatment means are to be activated for performing the measurements and/or treatments, only those measurement and/or treatment means which realistically contribute to the measurement and/or treatment are activated, which may increase the life time of the of the probe 10, and thus of the system according to embodiments of the invention.

In a second aspect, the present invention provides a method for controlling measurement and/or treatment means of a probe 10. The method comprises: measuring pressure for detecting target locations where contact is made between the probe 10 and skin 13 of a human or animal body, thereby generating a feedback signal indicative of such target locations, and selectively driving measurement and/or treatment means based on the feedback signal so as to selectively activate the measurement and/or treatment means positioned at the detected target locations. Detecting target locations where contact is made between the probe 10 and the skin 13 of the human or animal body may be performed by determining whether a force not smaller than a predetermined force, e.g. a force of at least 5 g/cm² or at least 10 g/cm², is applied by the probe 10 to the skin 13. It is decided that contact is made when a force not smaller than the predetermined force, e.g. a force of at least 5 g/cm² or at least 10 g/cm², is detected during a predetermined time period, e.g. a time period of longer than 0.1 sec, a time period of longer than 1 sec or a time period of longer than 2 sec, for example longer than 4 sec.

According to embodiments of the invention, the measurement and/or treatment means may comprise a plurality of light sources, e.g. optical fibres 14. According to these embodiments, selectively activating the measurement and/or treatment means may be performed by activating at least some of the optical fibres 14. According to other embodiments of the invention, the measurement and/or treatment means may comprise a radiation source for generating a radiation bundle in a light guide 18, a shield 20 comprising separately drivable multi-switches. According to these embodiments, selectively activating the measurement and/or treatment means may be performed by selectively activating the multi-switches of the shield 20 such that at least part of the multi-switches are driven based on the feedback signal so as to open and to allow the radiation getting through the shield 20 at particular positions.

According to embodiments of the invention, the measurement and/or treatment means may further more comprise a plurality of measurement elements 16 such as e.g. optical, ultrasound, photo acoustic elements and selectively activating the measurement and/or treatment means may furthermore be performed by selectively activating the measurement elements 16.

According to further embodiments of the invention, the skin 13 of a human or animal body may lie in a plane and measuring the physiological parameter may be performed by providing the probe 10 such that it makes an angle CC of between 0° and 90° with a direction substantially perpendicular to the plane of the skin 13. According to embodiments of the invention, the method may furthermore comprise changing the angle CC of the probe 10 with respect to the direction substantially perpendicular to the plane of the skin 13 and repeating the steps as described above. Fig. 6 illustrates an example of an algorithm which may be used with the method according to embodiments of the present invention.

The measurement of the physiological parameter and/or treatment of the human or animal body may be performed by placing the probe 10 so that it makes an angle CC of between 0° and 90° with a direction substantially perpendicular to the plane of the skin 13. First, target locations are detected where contact is made between the probe 10 and the skin 13 of the human or animal body. According to the present example this may be done by detecting forces at different locations along the contact surface 12 of the probe 10 (step 30). Those locations where a force not smaller than a predetermined force, e.g. a force of at least 5 10 g/cm² or at least 10 g/cm², is measured for a predetermined time period, e.g. a time period of at least 0.1 sec, at least 1 sec or at least 2 sec, for example at least 4 sec, may be considered target locations, i.e. locations where the probe 10 adequately touches the skin 13 of the human or animal body (step 40). This is to avoid determining 'fake' contacts caused by occasional or accidental touches as target locations. The target locations may then be defined and stored, e.g. in a memory in the controller 17 (step 50). All target locations together may form a target area where measurements and/or treatments may be performed. From this result, an active range of the probe 10 may be determined (step 60). With active range is meant the part of the probe 10, i.e. those measurement and/or treatment means that have to be selectively activated for performing the measurement and/or treatment. Next, the measurement and/or treatment means which are part of the determined active range are then selectively activated, thereby making use of a feedback signal derived from the parameters of the stored target locations (step 70). After that, the measurement of the physiological parameter and/or treatment may be performed (step 80). In case of measurement of a physiological parameter, as a result values for the physiological parameter as a function of location may be obtained (step 90). The physiological parameter is measured at a number of locations which were found to meet the criteria of good contact as described above. The system 110 according to embodiments of the invention facilitates measurement and/or treatment on these multiple locations (e.g. corresponding to multiple shield-elements). In such a way, in case of treatment, an area can be treated by sequentially or simultaneously opening the multiple shield-elements that define the treatment area. In case of sensing or measuring, an image can be taken by sequentially scanning over the multiple locations.

According to the present example, the steps of the method as described above may be repeated at least once with the probe 10 placed under a different angle CC than the previous measurement (step 100). In that case, after having performed at least two measurements, a spectrum on the average value of the physiological parameter may be obtained. This may increase preciseness of the measurement.

In a further aspect, the present invention also provides a system controller 17 for use in a system 110 according to embodiments of the present invention for controlled or selective driving of a probe 10. The system controller 13, which is schematically illustrated in Fig. 7, may comprise a control unit 21 for controlling, i.e. selectively activating parts of a measurement and/or treatment means depending on a feedback signal indicative of target locations where contact exists between the probe 10 and the skin 13. The controller 17 may selectively drive the measurement and/or treatment means according to an algorithm as, for example, illustrated in Fig. 6 and which may be stored in the controller 17. Therefore, the control unit 17 may comprise a memory 22 e.g. electronic memory to store the algorithm.

The control unit 21 may include a computing device, e.g. microprocessor, for instance it may be a micro-controller. In particular, it may include a programmable controller, for instance a programmable digital logic device such as a Programmable Array Logic (PAL), a Programmable Logic Array, a Programmable Gate Array, especially a Field

Programmable Gate Array (FPGA). The use of an FPGA allows subsequent programming of the micro fluidic system, e.g. by downloading the required settings of the FPGA. The control unit 21 may be operated in accordance with settable parameters, such as driving parameters, for example temperature and timing parameters. The method described above according to embodiments of the present invention may be implemented in a processing system 200 such as shown in Fig. 8. Fig. 8 shows one configuration of processing system 200 that includes at least one customizable or programmable processor 41 coupled to a memory subsystem 42 that includes at least one form of memory, e.g., RAM, ROM, and so forth. It is to be noted that the processor 41 or processors may be a general purpose, or a special purpose processor, and may be for inclusion in a device, e.g., a chip that has other components that perform other functions. Thus, one or more aspects of the method according to embodiments of the present invention can be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. The processing system may include a storage subsystem 43 that has at least one disk drive and/or CD-ROM drive and/or DVD drive. In some implementations, a display system, a keyboard, and a pointing device may be included as part of a user interface subsystem 44 to provide for a user to manually input information, such as parameter values. When the system 110 according to embodiments of the invention is used with a measurement probe 10, i.e. with a probe 10 comprising measurement means, an example of such a parameter value may be pressure threshold, which may depend on whether the measurement probe 10 is used at home or in a hospital environment.

When the system 110 according to embodiments of the invention is used with a treatment probe, i.e. with a probe 10 comprising treatment means, the amount of delivered energy could be a user input. For example for hair removal by light, there may be different intensity settings of the energy of the light on the device, for example depending on the type of hair to be removed.

More elements such as network connections, interfaces to various devices, and so forth, may be included, but are not illustrated in Fig. 8. The various elements of the processing system 40 may be coupled in various ways, including via a bus subsystem 45 shown in Fig. 8 for simplicity as a single bus, but will be understood to those in the art to include a system of at least one bus. The memory of the memory subsystem 42 may at some time hold part or all (in either case shown as 46) of a set of instructions that when executed on the processing system 40 implement the steps of the method embodiments described herein.

The present invention also includes a computer program product which provides the functionality of any of the methods according to embodiments of the present invention when executed on a computing device. Such computer program product can be tangibly embodied in a carrier medium carrying machine-readable code for execution by a programmable processor. The present invention thus relates to a carrier medium carrying a computer program product that, when executed on computing means, provides instructions for executing any of the methods as described above. The term "carrier medium" refers to any medium that participates in providing instructions to a processor for execution. Such a medium may take many forms, including but not limited to, non-volatile media, and transmission media. Non- volatile media includes, for example, optical or magnetic disks, such as a storage device which is part of mass storage. Common forms of computer readable media include, a CD-ROM, a DVD, a flexible disk or floppy disk, a tape, a memory chip or cartridge or any other medium from which a computer can read. Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to a processor for execution. The computer program product can also be transmitted via a carrier wave in a network, such as a LAN, a WAN or the Internet. Transmission media can take the form of acoustic or light waves, such as those generated during radio wave and infrared data communications. Transmission media include coaxial cables, copper wire and fibre optics, including the wires that comprise a bus within a computer.

It is to be understood that although preferred embodiments, specific constructions and configurations, as well as materials, have been discussed herein for devices according to the present invention, various changes or modifications in form and detail may be made without departing from the scope of this invention as defined by the appended claims.

Claims

CLAIMS:

1. A system (110) for controlling measurement and/or treatment means of a probe (10), the system (110) comprising: a probe (10) with an outwardly curved probe head (11) having a contact surface (12) adapted for contacting skin (13) of a human or animal body, a plurality of pressure sensors (23) distributed over the contact surface (12), the plurality of pressure sensors (23) being for obtaining a feedback signal indicative of target locations where contact exists between the probe (10) and skin (13) of the human or animal body, and a controller (17) adapted for selectively driving measurement and/or treatment means located at the target location based on the feedback signal from the pressure sensors (23).

2. A system (110) according to claim 1, furthermore comprising a plurality of measurement and/or treatment means distributed over the contact surface (12) of the probe head (11).

3. A system (110) according to claim 2, wherein the measurement and/or treatment means comprises illumination means.

4. A system (110) according to claim 3, wherein the measurement means furthermore comprises measurement elements (16).

5. A system (110) according to any of claims 3 or 4, wherein the illumination means comprises a plurality of optical fibres (14) of which ends (15) are distributed in the probe head (11).

6. A system (110) according to any of claims 3 or 4, wherein the illumination means comprises a radiation source for generating a radiation bundle in a light guide (18) and a shield (20) comprising multi-switches which can separately and selectively be driven.

7. A system (110) according to any of the previous claims, furthermore comprising a memory (22) for storing a value representative of the feedback signal.

8. A system (110) according to any of the previous claims, wherein the probe

(10) is a measurement probe for measuring a physiological parameter of the human or animal body.

9. A method for making a system (110) for controlling measurement and/or treatment means of a probe (10), the method comprising: providing a probe (10) with an outwardly curved probe head (11) having a contact surface (12) adapted for contacting skin (13) of a human or animal body, providing a plurality of pressure sensors (23) distributed over the contact surface, the plurality of pressure sensors (23) being adapted for obtaining a feedback signal indicative of locations where contact exists between the probe (10) and skin (13) of the human or animal body, providing a controller (17) adapted for selectively driving measurement and/or treatment means based on the feedback signal from the pressure sensors (23).

10. A method according to claim 9, furthermore comprising providing measurement and/or treatment means distributed over the contact surface (12) of the probe head (11).

11. A method for controlling measurement and/or treatment means of a probe (10), the method comprising: measuring pressure for detecting target locations where contact is made between the probe (10) and skin (13) of a human or animal body, thereby generating a feedback signal indicative of such target locations, selectively driving measurement and/or treatment means based on the feedback signal so as to selectively activate those measurement and/or treatment means positioned at the detected target locations.

12. A method according to claim 11, furthermore comprising measuring a physiological parameter of the human or animal body or performing a treatment on the human or animal body.

13. Method according to any of claims 11 or 12, wherein detecting target locations is performed by determining whether a force not smaller than a predetermined force is applied by the probe (10) to the skin (13) during at least a predetermined time period.

14. Method according to any of claims 11 to 13, the skin (13) lying in a plane and controlling measurement and/or treatment means of a probe (10) being performed by providing the probe (10) such that it makes an angle (α) of between 0° and 90° with a direction substantially perpendicular to the plane of the skin (13), wherein the method furthermore comprises changing the angle (α) of the probe (10) with respect to the direction substantially perpendicular to the plane of the skin (13) and repeating the pressure measuring and selectively driving steps.

15. Controller (17) for controlled driving of measurement and/or treatment means of a probe (10), the controller (17) comprising a control unit (21) for selectively activating the measurement and/or treatment means in accordance with a feedback signal indicative of target locations where contact exists between the probe (10) and skin (13) of a human or animal body.