Device and method for assessing thermoalgesic and vibratory sensitivity

Abstract

The invention relates to a device for assessing thermoalgesic and vibratory sensitivity, including a first unit (1) configured to apply, to localized points of the patient, a plurality of stimuli comprising vibrations and temperature changes, a second unit (2) for gathering data communicating with the first unit, wherein the communication between the first unit (1) and the second unit (2) takes place by means of a two-way wireless transmission means. The invention also relates to a method for assessing vibratory, thermal and thermoalgesic sensitivity using the device according to the invention.

Claims

1. Device for assessing thermoalgesic and vibratory sensitivity, comprising: a first unit configured to apply to localized points of a patient a plurality of stimuli comprising vibrations and temperature changes, a second unit for communicating with the first unit via wireless transmission, wherein the first unit comprises: an outer casing, a tuning fork that has two arms converging on a central point for applying vibration and a Peltier cell with ventilators for generating cold-heat to apply a plurality of stimuli to localized points of the patient body, an ejecting arm adapted to move respect to the outer casing in order to deploy the Peltier cell with ventilators, and an electrical circuit adapted to vary the intensity of the plurality of stimuli comprising the vibration from the tuning fork and the cold-heat from the Peltier cell, wherein the ventilators are configured to rotate around an axis perpendicular to an axis of the outer casing, wherein the ejecting arm is disposed parallel to said axis and is connected to the outer casing to move with respect to the outer casing according to a direction parallel to the axis, in such a way that when the ejecting arm is: in a deployed position, the ejecting arm and the Peltier cell with ventilators project from the outer casing and the Peltier cell with ventilators is configured to adopt an inclination with respect to the axis of the outer casing and with respect to an angle of the Peltier cell with ventilators when the ejecting arm is in a retracted position; wherein the second unit comprises: a power button, and two buttons for the input of data to operate the tuning fork that has two arms and the Peltier with ventilators, an indicator for indicating different operational stages of the first unit, and wherein the device is adapted to execute a quantification programme to quantify a response capacity of the patient to the plurality of stimuli, wherein said response capacity is based on a score derived from a group of responses to the plurality of stimuli; wherein the response capacity is affirmative when at least one of the plurality of stimuli is detected by the patient or negative when the at least one of the plurality of stimuli is not detected by the patient, wherein the first and second units are configured to implement a self-test after the first and second units are turned on, said self-test comprising an assessment of a battery charge, an ambient temperature, a skin temperature, a radiofrequency or infrared communication status, wherein the first and second units are configured to be powered electrically and autonomously, wherein the outer casing comprises a rubber washer on a tip of the outer casing, wherein a piezo-electrical element of 125 to 248 Hz or a speaker with coil for generating the vibrations is fixed to a free end of each of the two arms of the tuning fork.

2. The device of claim 1, wherein the first unit comprises a skin temperature sensor and an ambient temperature sensor adapted to determine temperature to be able to carry out the assessment.

3. The device of claim 1, wherein the first unit remains coupled to the second unit through a slot made in the second unit and a projection that fits into said slot associated to the first unit, in such a way that both units are coupled to each other, forming the device.

4. The device of claim 1, wherein the first unit comprises a base configured to rest on the ground during use of the device and a rubber layer on the base.

5. The device claim 1, wherein the indicator comprises a plurality of LEDS of different colours including red and green, whereby the LED of red colour is configured to light up when the plurality of stimuli is being applied by the first unit and, the LED of green colour is configured to light up to indicate to the patient to push a first button when the patient identifies the vibration, or a second button configured to be pushed when the patient identifies no vibration.

6. The device of claim 1 wherein a screen configured to display at least the following data: date and time, a number and type of test being carried out, a score obtained in each test and in total, and a percentage of the plurality of stimuli detected by the patient.

7. The device of claim 1, wherein the device is portable.

8. The device claim 1, wherein the plurality of stimuli is applied during a vibration stimulation programme comprising a plurality of vibrations randomly selected from the group consisting of 5.77 m, 2.38 m, 1.19 m and 0.01 m.

9. The device of claim 8, wherein the quantification programme is configured to enter self-suspension when more than two vibrations of 0.01 pm are given affirmative responses by the patient, and then indication is given on a data display that the test has failed and the need to start, again, wherein said data display is a screen.

10. The device of claim 1, wherein the response results are assessed in percentiles and the test result is deemed abnormal when the group of responses gives an affirmative response of lower than 75%.

11. The device of claim 10 wherein, when a test result is deemed abnormal, a warning flashing red light will come on.

12. The device of claim 11, wherein when said test result is deemed abnormal, an alarm is sounded.

Description

BRIEF DESCRIPTION OF THE DESIGNS

(1) FIG. 1 represents a view of the device integrating the first and second units.

(2) FIG. 2 represents a perspective front view of the device integrating the first unit for assessing sensitivity, object of the present invention, said first unit being in retracted position. In FIG. 2b a lateral perspective view of said device is represented.

(3) FIG. 3 represents a perspective view of the first unit in deployed position.

(4) FIG. 4 represents a perspective view of the first unit forming part of the device for assessing sensitivity, object of the present invention, said first unit being in partly deployed position.

(5) FIG. 5 represents a perspective view of the first unit forming part of the device for assessing sensitivity, object of the present invention, said first unit being in fully retracted position.

(6) FIG. 6 represents a perspective view of the second unit forming part of the device for assessing sensitivity, object of the present invention.

(7) FIG. 7 represents a perspective view of the vibration generating means forming part of the first unit of the device.

DESCRIPTION OF A PREFERRED EMBODIMENT

(8) As can be seen in FIG. 1, the device for assessing the vibratory and thermoalgesic sensitivity, object of the present invention, is essentially made up of a first unit (1) and a second unit (2) that, when the device is being used, are mutually integrated thanks to a slot made in the second unit (2) and a protrusion or projection fitting perfectly inside said slot, said projection being made in the first unit (1).

(9) The first unit (1) is made up of an outer casing (3) with a cylindrical configuration and that is divided into two parts (37) and (38), this unit having a sleeve on each of the two ends or a single sleeve (39) between the two parts, whereby thanks to a relative turn of both parts of the first unit (1) a vibration generating means (4) or a means generating cold-heat (4), or both simultaneously if necessary, may be deployed.

(10) In FIG. 3 the constitution of the first unit (1) is detailed, which in addition to the mentioned stimuli-generating means (4) and (4), includes on/off and control (5) means, whose mission is, on one hand, to allow the switching on and off of the first unit (1) and, on the other hand, to control by means of an electrical circuit (5) the intensity of the stimuli applied to the patient, both vibrations and cold-heat.

(11) The vibration generating means (4) comprise a tuning fork (9), represented in detail in FIG. 7, which consists of arms (10) that converge on a central point (11) crossed by a stem (40) that makes up the vibration applicator (12), which has in its free end a Teflon button (13). In the connection area between said applicator (12) and the casing (3) is a rubber washer (14) to prevent the leakage of vibrations. On each end of the arms (10) the corresponding piezo-electric elements (248-125 Hz) or speakers that have an inner coil are arranged, which are responsible for generating the vibration, as they emit a vibratory discharge through the changes experienced by the piezo-electric unit in response to the electrical stimulus of this element, or through sound generating a vibratory effect in conjunction with the coil and with a frequency phase shift of 180, leading to transmission through the arms of the tuning fork (9) to the applicator (12). The energy feeding the first unit (1), which is destined to said vibration generating means (4), is of 9 V, maintaining a vibration with a sinusoidal wave form of 4 milliseconds duration.

(12) The vibration generating means (4) may be optionally displaced linearly with respect to the casing (3), being deployed from it through activation of the sleeve (39), enabling the means in the inside of the first unit that are appropriate for achieving said displacement.

(13) For example, guides may be enabled (41).

(14) On the other hand, the means generating cold-heat (4) have a Peltier cell with ventilators (16), in particular a Peltier thermode with ventilators, which is arranged on the end of an ejector arm (19), in parallel to the turning axis (18) of the casing (3), being rotatable with respect to said arm (19) according to an axis (17) perpendicular to the turning axis (18). In this way, in the idle state of the first unit (1), the casing contains a Peltier cell with ventilators (16) that by turning the sleeve (39) is extracted from the casing (3) projecting the arm (19), on the end of which the cell (16) lies in retracted position, because the diameter of the casing (3) is smaller than the necessary width for the Peltier cell with ventilators, as can be seen in FIG. 4. To be able to use the cell (16), it is retracted with respect to the arm's end (19) according to the rotational axis (17), resulting in it being completely deployed and ready for use.

(15) In FIG. 5 the first unit (1) can be seen, in which the Peltier cell with ventilators (16) and the vibration applicator (12) have been completely deployed. A support element (42) of the first unit (1) can also be seen, which couples to the casing (3) through a hole made in it, said element (42) having a rubber base (34) to prevent vibrations from the ground transmitting to the first unit (1). The first unit (1) may have temperature sensors, a skin sensor (29) and an ambient temperature sensor (30) that are incorporated on the thermoalgesic unit containing the Peltier cell with ventilators.

(16) In FIG. 6, the configuration of the second unit (2) is shown, which consists of means for data input (6), means for data display (7) and indicator means (8). The data input means are embodied in a button pad (20) that has a first area (21) of buttons comprising a button for the switching on and off and another area with two buttons for the input of data corresponding to the vibration generating means and for input of data corresponding to the means generating cold-heat, and a second area (22) of buttons having a first button (23) that will be pushed when the patient identifies a vibration and a second button (24) that will be pushed when the patient identifies none.

(17) The main aim of the button pad is to register the detection of the different stimuli by the patient being assessed; thus the first button (23) corresponds to the capture of affirmative data (yes) regarding the identification of stimuli, while the second button (24) corresponds to the capture of negative data (no), or the lack of identification of the stimuli. Regarding the data display means (7), they comprise a screen (44) that can display at least the following data: the date and time when the assessment or test is carried out, the number and type of test being run, the score obtained in each test and in total, and the percentage of stimuli detected by the patient.

(18) The indicator means (8) are several leds (36) red and green in colour, whereby the led will light up red when the stimulus is being applied by the unit (1); it will subsequently stop lighting up and the green colour led will light up, indicating that at that moment the patient may proceed to pushing the buttons of the second unit (2).

(19) Additionally, the second unit (2) will have visual warning means (35) that may appear on the screen itself, and/or aural, which indicate the battery charge (33) of the unit is near exhaustion and also may warn about the test results if they exceed certain predetermined values. In addition, it may have a connection port (27) for the second unit (2) to a personal computer with the aim of processing the data collected by said unit if necessary. This unit (2) may have emergency batteries that will activate in the case the battery (33) is exhausted during the assessment process.

(20) The Peltier cell with ventilators (16) will have a dimension of 52.5 cm.sup.2, and the tuning fork (9) a working frequency of 125 to 248 Hz. The increases or decreases of the stimulation temperatures used for the Peltier cell with ventilators (16) consist of pre-established random ramps ranging from 9 (pyramidal scale) for cold, 45 for the feeling of heat, to a limit of 49 (trapezoid scale) for the feeling of thermal pain. Each stimulus is maintained for a period of 10 seconds and 3 stimuli are repeated in one same period, except for the pain resulting from only one stimulus.

(21) The responses to the five sensorial parameters assessed (cold, heat, thermal pain and vibration), are, in turn, registered in the second unit (2). Each response (pulsation of the appropriate button) should be given after application of the corresponding stimulus with a decision time of 10 seconds. Thus, each test (cold, heat, thermal pain and vibration) should provide data from 3 responses assigned to 3 stimuli of the same type but of different intensity. The thermal pain stimulus is applied only on one occasion, so it throws up a response result.

(22) The covering material of units (1) and (2) is hard (not flexible) plastic, similar to metal, in the same way as the internal structure, for external protection and protection of components.

(23) According to the disclosed configuration of the device, the assessment procedure is carried out in the following way.

(24) The first (1) and second (2) units are switched on.

(25) A self-test is carried out of said units, testing among other data, the battery charge (33), the date and operational status of radiofrequency or infrared communications between both units.

(26) Assessment Test for Sensitivity to Vibrations

(27) Reference is made to FIG. 15, an exemplary quantification programme for conducting Cold/Heat/Temperature or Vibration pain sensitivity test.

(28) As shown, the Vibration pain sensitivity test starts at step 151. Turning the sleeve (39) of the first unit (1) clockwise (the sleeve may be optionally located on the distal end, corresponding to the vibrator outlet) while holding fixedly the shortest portion (38) of the casing (3), the vibrations applicator (12) is telescopically extracted from the first unit (1).

(29) At step 152, the applicator (12) is placed in contact with the skin area just before the nail bed of the first toe of the right foot, then on the second toe, and continuing in the same way with the left foot. If necessary, one may proceed in the same way with the upper limbs. The contact between the surface of the applicator and the skin must be complete.

(30) The insulating rubber plate is placed under the skin bed of each finger explored.

(31) The vibration test session is initiated.

(32) The complete examination of vibration stimuli is carried out, consisting of a total of 3 tests. Each test should generate 4 stimuli, i.e. a total of 12 stimuli and 12 responses.

(33) The selected method for the assessment is: the yes-no paradigm (two-interval forced choice, which has been included in the software installed in the units of the device).

(34) The intensities of stimuli consist of: A) High intensity; B) intermediate intensity; C) low intensity, and D) null intensity. Each of these intensities is always characterized by presenting a vibration wave of sinusoidal form with a duration of 4 milliseconds and a wave width of +100 m. a100 m (125 to 248 Hz) with a constant intensity for A) 5.77 m, B) 2.38 m, C) 1.19 m, and D) 0.01 m.

(35) The mode in which each test is carried out by the software programme is selected randomly as regards intensity and order of application of each stimulus according to the pre-established values in A), B), C) and D).

(36) The time duration of each stimulus is 1.8 s and the pause interval between each stimulus is 13 s.

(37) The beginning of the test is signalled by the lighting up of a red-colour led (36) in the second unit (2), and then the response must be decided (pulsation of the buttons on the second unit (2) by the patient), as the green-colour led (36) of the second unit (2) lights up. If the patient does not press any button after a stimulus, the response is interpreted as missed and is not given a value.

(38) The stimulation programmes indicated are used randomly and distributed in different intensity gradation scales in the successive tests, using the described alternatives and in all cases with 6 non-consecutive null stimuli, such as, for example:

(39) TABLE-US-00001 1 2 3 4 A D B D A D C D B D A D B D C D C D A D C D B D

(40) At step 153, the patient must indicate to the second unit (2) the perception received of the stimulus. If the stimulus is identified, the affirmative (yes) button (23) will be pushed, and if the stimulus is not identified, the negative (no) button (24) will be pushed.

(41) Each response is assessed in the quantification programme as:

(42) Response 1 (shown at step 154a): success (stimulus detected by the patient).

(43) Response 0 (shown at step 154b): error (stimulus not detected by the patient). These results may be assessed in percentiles.

(44) In steps 155 and 157a-b, the test result is deemed abnormal if the group of responses gives a success rate lower than 75%.

(45) If more than two null stimuli are given positive responses by the patient, the programme enters self-suspension, indicating on screen that the test has failed and the need to start again; if the error persists, the software will not allow continuation with tests until 48 hours have elapsed (the time needed to consult the error with the distributor and/or healthcare personnel).

(46) After completing the test, the result in percentage of correct responses is shown on the screen of the response unit. If the result is 75% or less, as shown in step 157a, a warning flashing red light will come on in step 158 (optionally a sound alarm), indicating that the test result is not normal.

(47) The results may be transferred to a personal computer and represented in numeric and/or graphical form. With these values one can identify for each area explored the stage at which the implemented tests are.

(48) Assessment Test for Sensitivity to Temperature

(49) As shown, the COLD-HEAT/THERMAL pain sensitivity test starts at step 151. By turning the sleeve (39) (or the sleeve located on the end with the Peltier plate with ventilators) counterclockwise and fixedly holding the longest portion (37) of the casing (3), the temperature and thermal pain stimulator (Peltier cell with ventilators (16)) one wishes to use are deployed.

(50) By using the sensors of the unit an ambient temperature measurement is made.

(51) By means of the sensors of the unit, a skin surface temperature measurement is made.

(52) A similar measurement is made for the vibration stimulus, quantifying the response capacity to the stimulus of the patient.

(53) In this case, in step 156, the sensitivity and specificity of tests should be validated by contrasting against the method in CASE IV and with patient controls that are healthy or diseased, determining responses obtained according to sex, site explored, age and physical variables.

(54) For a better understanding of the specification, the references used in drawings are listed below: 1. first unit 2. second unit 3. casing of first unit 4. vibration generating means of the first unit 4. means generating cold-heat 5. on/off and control means of the first unit 6. data input means of the second unit 7. data display means of the second unit 8. indicator means of the second unit 9. tuning fork 10. arms of the tuning fork 11. central point of the tuning fork 12. vibration applicator 13. Teflon button 14. rubber washer 15. speaker of tuning forkpiezo-electrical element 16. Peltier cell with ventilators 17. rotational axis of Peltier cell 18. turning axis of the casing 19. ejecting arm 20. button pad 21. first area button pad 22. second area button pad 23. a first button 24. second button 27. port 29. skin temperature sensor 30. ambient temperature sensor 33. batteries first unit 34. base layer of rubber first unit 35. warning means of the second unit 36. leds indicator means of the second unit. 37. part of casing 38. part of casing 39. sleeve deployed 40. stem of the tuning fork 41. guides 42. support element