Diagnosis of brain and spinal cord injury by bulbocavernosus reflex measurement
09730605 · 2017-08-15
Assignee
Inventors
- Debra J. Folkerts (Manhattan, KS, US)
- Karen Louise Finstrom McPhee (Williamsburg, VA, US)
- Gregory Ray Johnson (Nisswa, MN, US)
- Timothy Martin Gack (Walker, MN, US)
Cpc classification
A61H19/30
HUMAN NECESSITIES
A61B5/1107
HUMAN NECESSITIES
A61B5/202
HUMAN NECESSITIES
A61H2201/5048
HUMAN NECESSITIES
A61H2230/605
HUMAN NECESSITIES
A61H2201/10
HUMAN NECESSITIES
A61N1/36007
HUMAN NECESSITIES
A61H2201/501
HUMAN NECESSITIES
International classification
A61H19/00
HUMAN NECESSITIES
A61B5/00
HUMAN NECESSITIES
A61B5/11
HUMAN NECESSITIES
Abstract
A system and method is disclosed for measuring muscle reflexes (e.g., a bulbocavernosus reflex) as a tool for identifying/diagnosing dysfunctions (e.g., spinal cord abnormalities, bladder voiding dysfunction, and sexual organ dysfunction) non-invasively by using mechanical stimulation. The system and method includes a probe having a predetermined patient contacting portion, wherein when the contacting portion is moved into contact with a particular area of the patient (e.g., the patient's genitals), the contact induces a muscle reflex. The probe detects the pressure resulting from the contacting portion being abruptly and forcibly brought into contact with the particular area. Such detection is used to electronically initiate capture of electrical responses from a plurality of electrodes placed on the patient's skin in proximity to the particular area. Such electrical responses are processed to determine characteristics of the patient's reflexes of one or more muscles adjacent to the electrodes.
Claims
1. A method for diagnosing at least one of a brain injury and a spinal cord injury, comprising: providing a probe comprising: a housing with a bore therethrough, the housing comprising a piezoelectric disk, the disk electrically connected to an amplifier and activated by a power source; a stimulus plunger having first and second ends and a shaft that extends through the bore, the shaft being movable along a longitudinal axis and having an expanded portion that prevents the stimulus plunger from sliding out of an opening in the housing; and a compression spring that biases the second end of the stimulus plunger away from contact with the piezoelectric disk, wherein, when the stimulus plunger makes non-invasive contact with a patient's genital area, pressure from the stimulus plunger is transmitted to the genital area to induce a bulbocavernosus reflex; placing the stimulus plunger in non-invasive contact with the patient's genital area; activating the piezoelectric disk to generate an electromagnetic response indicative of the non-invasive contact; using the electromagnetic response to identify at least one electrical response indicative of the bulbocavernosus reflex from a plurality of electrodes placed on the patient's skin adjacent to the genital area; determining at least one quantity selected from the group of a time delay between the electromagnetic response and the at least one electrical response, a time duration of the at least one electrical response, a value indicative of a magnitude of the at least one electrical response, and an attenuation in the at least one electrical response; and comparing the quantity to a predetermined baseline.
2. The method of claim 1, further comprising storing data indicative of a history of activation of the probe.
3. The method of claim 1, wherein the piezoelectric disk comprises an electrical switch.
4. The method of claim 1, further comprising determining a voltage difference between the plurality of electrodes.
5. The method of claim 1, wherein the electrodes are placed on opposite sides of the patient's rectum.
6. The method of claim 1, further comprising identifying a length of time of the placing step.
7. A method for diagnosing at least one of a brain injury and a spinal cord injury, comprising: providing a probe comprising: a housing with an opening therethrough, the housing operably associated with a probe tip; a patient contact shield cap, adapted to cover the probe tip and having a shaft with an expanded portion that prevents the shaft from sliding out of the opening in the housing; and a single electrical conductor attached to the expanded portion and concentric to the shaft, wherein the shaft of the cap is slidable along an axis within a bore through the cap, extends through the bore, is movable along a longitudinal axis, and has an inner end attached to an elastomeric component, the elastomeric component adapted to fit within the recess and exert a force effective to cause the expanded portion to contact the interior of the cap, and wherein the inner end of the shaft and the elastomeric component are received in a recess within the probe and the shaft is slidable along the axis within the recess; abruptly contacting the cap with a patient's genital area, wherein the shaft slides along the axis and thereby compresses the elastomeric component by an amount effective to cause the conductor to contact a pair of electrodes that are spaced apart; detecting current flow between the electrodes to identify a time indicative of the cap contacting the patient for inducing a bulbocavernosus reflex; measuring a time delay of the bulbocavernosus reflex in the patient; and comparing the time delay of the bulbocavernosus reflex to a predetermined baseline, wherein, as a result of the abruptly contacting step, the electrical conductor moves toward the probe tip and slides past the pair of electrodes so that the flow of current between the electrodes ceases, and wherein the detecting step provides a signal effective for commencing the measuring step.
8. The method of claim 7, further comprising storing data indicative of a history of activation of the probe.
9. The method of claim 7, wherein the cap further comprises a flat spring provided along the shaft, the flat spring adapted to fold against the shaft in a first position and move toward the probe tip in a second position.
10. The method of claim 7, further comprising determining at least one of a duration of the bulbocavernosus reflex, a value indicative of a magnitude of at least one electrical response of the bulbocavernosus reflex, and an attenuation in the at least one electrical response of the bulbocavernosus reflex.
11. The method of claim 7, wherein the electrical conductor comprises an electrical switch.
12. The method of claim 7, further comprising determining a voltage difference between the electrodes.
13. The method of claim 7, wherein the electrodes are placed on opposite sides of the patient's rectum.
14. The method of claim 7, further comprising identifying a length of time of the abruptly contacting step.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION
(23) It is one aspect of the present invention to provide a method for diagnosing at least one of a brain injury and a spinal cord injury, comprising providing a probe; abruptly contacting a patient's genital area with the shield cap of the probe, wherein a shaft of the cap slides along a longitudinal axis and thereby compresses an elastomeric component of the cap by an amount effective to cause an electrical conductor of the probe to contact a pair of electrodes that are spaced apart; detecting current flow between the electrodes to identify a time indicative of the cap contacting the patient for inducing a bulbocavernosus reflex; measuring a time delay of the bulbocavernosus reflex in the patient; and comparing the time delay of the bulbocavernosus reflex to a predetermined baseline, wherein, as a result of the abruptly contacting step, the electrical conductor moves toward a probe tip of the probe and slides past the pair of electrodes so that the flow of current between the electrodes ceases, and wherein the detecting step provides a signal effective for commencing the measuring step. In various embodiments, the probe comprises a housing with an opening therethrough, the housing operably associated with the probe tip; the patient contact shield cap, adapted to cover the probe tip and having the shaft with an expanded portion that prevents the shaft from sliding out of the opening in the housing; and the single electrical conductor attached to the expanded portion and concentric to the shaft, wherein the shaft of the cap is slidable along an axis within a bore through the cap, extends through the bore, is movable along the longitudinal axis, and has an inner end attached to the elastomeric component, the elastomeric component adapted to fit within the recess and exert a force effective to cause the expanded portion to contact the interior of the cap, wherein the inner end of the shaft and the elastomeric component are received in a recess within the probe and the shaft is slidable along the axis within the recess.
(24) In certain embodiments, the method further comprises storing data indicative of a history of activation of the probe.
(25) In certain embodiments, the cap further comprises a flat spring provided along the shaft, the flat spring adapted to fold against the shaft in a first position and move toward the probe tip in a second position.
(26) In certain embodiments, the method further comprises determining information representative of at least one of a duration of the bulbocavernosus reflex, a value indicative of a magnitude of at least one electrical response of the bulbocavernosus reflex, and an attenuation in the electrical responses of the bulbocavernosus reflex.
(27) In certain embodiments, the electrical conductor comprises an electrical switch.
(28) In certain embodiments, the method further comprises determining a voltage difference between the electrodes.
(29) In certain embodiments, the electrodes are placed on opposite sides of the patient's rectum.
(30) In certain embodiments, the method further comprises identifying a length of time of the abruptly contacting step.
(31) It is another aspect of the present invention to provide a method for diagnosing at least one of a brain injury and a spinal cord injury, comprising providing a probe comprising a housing with a bore therethrough, the housing comprising a piezoelectric disk, the disk electrically connected to an amplifier and activated by a power source; a stimulus plunger having first and second ends and a shaft that extends through the bore, the shaft being movable along a longitudinal axis and having an expanded portion that prevents the stimulus plunger from sliding out of an opening in the housing; and a compression spring that biases the second end of the stimulus plunger away from contact with the piezoelectric disk, wherein, when the stimulus plunger makes non-invasive contact with a patient's genital area, pressure from the stimulus plunger is transmitted to the genital area to induce a bulbocavernosus reflex; placing the stimulus plunger in non-invasive contact with the patient's genital area; activating the piezoelectric disk to generate an electromagnetic response indicative of the non-invasive contact; using the electromagnetic response to identify at least one electrical response indicative of the bulbocavernosus reflex from a plurality of electrodes placed on the patient's skin adjacent to the genital area; determining at least one quantity selected from the group of a time delay between the electromagnetic response and the at least one electrical response, a time duration of the at least one electrical response, a value indicative of a magnitude of the at least one electrical response, and an attenuation in the at least one electrical response; and comparing the quantity to a predetermined baseline.
(32) In certain embodiments, the method further comprises storing data indicative of a history of activation of the probe.
(33) In certain embodiments, the piezoelectric disk comprises an electrical switch.
(34) In certain embodiments, the method further comprises determining a voltage difference between the plurality of electrodes.
(35) In certain embodiments, the electrodes are placed on opposite sides of the patient's rectum.
(36) In certain embodiments, the method further comprises identifying a length of time of the placing step.
(37) In various embodiments, the screening system and method disclosed herein includes mechanical stimulation of the penis or clitoris performed by a novel probe 10, wherein a first embodiment of this probe is shown in
(38) At a very high level, the probe 10 is used to contact the patient's clitoris or penis and in particular, a probe tip 34 (referred to more generally hereinabove as a “patient contacting portion”) contacts the patient's clitoris or penis for thereby inducing a patient reflex response. The detection of the probe tip 34 contacting the clitoris or penis is accomplished by the probe 10 outputting an electrical signal indicative of the stimulus plunger 13 contacting the piezoelectric disk 12. The BCR in response to such contact is then detected by electrical signals output from properly positioned electrodes 2 on the patient's skin. Subsequently, such signals are amplified and then analyzed for determining/identifying characteristics of the amplified signals (and/or a graph thereof), wherein such characteristics may be used for identifying patient ailments and/or providing a patient diagnosis.
(39) The compression spring 15, and plunger housing 14 restrain the stimulus plunger 13 in such a way that it can only move along the axis 16, and in particular, towards the piezoelectric disk 12 when the stimulus plunger tip 34 comes in contact with another object (e.g., a patient) with sufficient force to overcome the opposing force of the compression spring 15. Accordingly, when the stimulus plunger tip 34 comes in contact with a patient with such force so that the stimulus plunger 13 comes in contact with the piezoelectric disk 12 (while the disk is electrically activated), the disk distorts its shape (e.g., bends), and the mechanical stress caused by the stimulus plunger 13 contacting the piezoelectric disk 12 causes an electrical charge to develop on the surface of the piezoelectric disk 12. Since the disk 12 is electrically connected to an amplifier 36 (via the connection 19 and the external conductor 38), the electrical charge induced on the disk is detected by the amplifier for amplification (and at least in some embodiments, filtered as well via a high pass filter). Thus, the disk 12 functions as a sensor for detecting contact between a patient and the tip 34. However, alternative sensors may be used to detect the transfer of pressure from the tip 34 to the disk 12. In particular, the opposing end 30 may include a pressure sensitive switch (not shown) for detecting contact with the disk 12.
(40) In one preferred embodiment, the probe 10 may be handheld by an operator for placing the probe in contact with a patient's penis or clitoris for initiating bulbocavernosus reflex. Moreover, in one preferred embodiment, the contact of the probe tip 34 with the patient's clitoris or penis is performed by an abrupt, non-invasive, pressure inducing motion that is preferably somewhat unexpected by the patient. Such a motion may be similar to inducing patellar reflexes during an examination of a patient's knee reflexes.
(41) A battery 17 (e.g., internal to the probe), or a transformer (e.g., external to the probe, and not shown) may be used to electrically activate the disk 12 for detecting contact by the end 30 when genital simulation is performed via contact with the tip 34 of the shaft 18 (which extends through the bore 22).
(42) Although such piezoelectric disks 12 may generate mechanical or pressure vibrations (i.e., oscillations in directions coincident with axis 16,
(43) The amplifier 36 (e.g., an EMG amplifier and high pass filter) amplifies the detected charge on the disk 12 induced by genital stimulation. The amplifier 36 responds by outputting a corresponding amplified response signal on the transmission cable 44 for transmission to a computer 40. The computer 40 is programmed to receive the probe 10 amplified signal as input, and assuming an electrical potential is being concurrently applied to the reference electrode 4 (e.g., via the DC voltage source 42), the amplified probe signal on the cable 44 act as a trigger to activate a signal conversion process 48 for commencing to sample the amplified electrode 2 signals output by the amplifier 36 via the surface electromyography (SEMG) unit 35. The computer 40 then converts the amplified signals from the electrodes 2 into a time series of numbers representing the magnitudes of the samples. In particular, the amplified electrode signals output on connection 46a are amplifications of the differences of signals derived from the sensing electrodes 2 (
(44) As shown in
(45) Note that the probe 10 (and in some embodiments, only the probe tip, as discussed in other sections hereinbelow) may be a single patient use device (i.e., non-reusable), e.g., the probe (or probe tip) is, in at least preferred embodiments, deactivated after it has been attached to the computer 40 for, e.g., an extended time period of such as 30 minutes. Such an extended time period gives an operator of the screening system and method ample time to obtain measurements of the bulbocavernosus reflex desired for the screening process. Note that when the probe 10 is battery powered such deactivation may be provided by a draining of the one or more batteries; e.g., once the probe is activated, current continues to flow from the one or more batteries until the batteries cannot power the probe. However, it is within the scope of the present disclosure that other methods of deactivating such batteries may be used, such as having an operator manipulate a deactivation switch that permanently disconnects the electrical power to the piezoelectric disk 12, or by providing an electronic timer in the probe 10 that activates with the first activation of the probe and deactivates the probe after a predetermined time has elapsed.
(46) Amplified voltage signals derived from the difference of the signals output by the sensing electrodes 2 are provided to the computer 40, and in particularly, to the signal conversion process 48. The amplified voltage signals include signals representative of the potential (voltage) differences between the sensing electrodes 2 as determined by the SEMG 35.
(47) However, in an alternative embodiment, the wires 46b may connect directly to the amplifier 36 for simply amplifying and outputting each of its input electrode 2 signals. In such an embodiment, the signal conversion process 48 computes values representative of the potential differences between the sensing electrodes 2. Note that the SEMG 35 is not required in this embodiment.
(48) Using the output from the amplifier 36, the signal conversion process 48 performs an analog to digital conversion, wherein the signals on the connection 46a are sampled, digitized, and then the digitized samples are input to a computational procedure for generating a time series of records (e.g., a series of measurement records) representing the magnitude of the amplified signals over a predetermined elapsed time. More specifically, for each sampling period, the connection 46a is sampled, the obtained sample is used to determine a number in a predetermined range of, e.g., 0 to 4096, wherein the greater the number, the greater BCR, and wherein such numbers from different reference electrode voltages can be reliably compared, summed, averaged or otherwise combined if desired. Moreover, the values in this predetermined range may be then normalized to the range 0.0 to 1.0, as one of ordinary skill in the art will understand.
(49) However, it is within the scope of the present disclosure that, instead of the resulting time series of BCR numbers being monotonic with the BCR, such numbers may be inversely related to the BCR. Accordingly, instead of 1.0 being indicative of a maximal BCR response as is computed in the steps above, 0.0 would be indicative of the maximal BCR response.
(50) The time period between samplings may be, e.g., 1.0 millisecond, although alternative time periods that are smaller or larger are within the scope of the present disclosure.
(51) In one embodiment of the screening system and method, an analog to digital converter separate from the computer 40 may receive the signals from the amplifier 36 for performing the signal conversion process 48.
(52) However, regardless of where the analog to digital conversion is performed, subsequently the analysis process 60 described hereinbelow is performed.
(53) The analysis process 60 may be instrumental in determining BCR patient data to be output to the display device 52 (
(54) (a) a latency between the detection of the response signal on cable 44, and commencement of the BCR signals from the electrodes 2,
(55) (b) a duration of the BCR signals from the electrodes 2,
(56) (c) a value indicative of a magnitude or strength of the BCR, and/or
(57) (d) an attenuation in the magnitude or strength of the BCR (e.g., in comparison to an expected magnitude or strength).
(58) Additionally, as described hereinbelow, the analysis process 60 may also determine associations between, e.g., values such as (a) through (d) immediately above, and likely a diagnosis of a patient's symptoms.
(59) In order to more fully describe the processing and output of the analysis process 60, a description of a representative embodiment of output 56 (
(60) In one embodiment, the position of the line 66 is manually assigned by an operator, wherein, e.g., the operator is able to set (and/or select and drag) this line to the position the operator determines is most indicative the onset of the BCR. However, in an alternative embodiment, the position of the line 66 may be estimated by the screening system and method, e.g., by identifying an initial time where the graphical signature 68 remains above a predetermined threshold for a predetermined elapsed time.
(61) A patient symptom can be entered in the interaction box 76, and the collected patient data, and/or measurements/characteristics derived therefrom, can be associated with this symptom. Accordingly, once an actual diagnosis of the cause of the symptom is determined for each of a plurality of patients, associations may be obtained between: (i) such actual diagnoses, and (ii) the symptoms and corresponding measurements/characteristics of the collected patient data (e.g., patient graphical signatures 68). In particular, such associations may become the basis for one or more predictive models for predicting a likely (if any) patient abnormality/diagnosis, wherein such associations may be formed by one or more of: a statistical method (e.g., a regression technique), a learning system (e.g., a vector machine, and an artificial neural network), and/or a pattern matching system (e.g., a fuzzy logic system, etc.). In particular, it is believed that such associations may be based substantially on the symptom identification together with one or more of the following BCR measurements:
(62) (a) a latency between the graphical signature 68 (equivalently, the BCR signals from the electrodes 2), and the detection of the response signal on cable 44,
(63) (b) a duration of the graphical signature 68 (equivalently, the BCR signals from the electrodes 2),
(64) (c) a magnitude of the graphical signature 68 (equivalently, the BCR signals from the electrodes 2),
(65) (d) an attenuation in the magnitude of the graphical signature 68 (equivalently, the BCR signals from the electrodes 2), wherein such attenuation is, e.g., in comparison to an expected magnitude, and/or
(66) (e) no detectable graphical signature 68 (equivalently, the BCR signals from the electrodes 2).
(67) Alternatively or additionally, the resulting time series of the digital data stream from the signal conversion process 48 can be input to an embodiment of analysis process 60 for hypothesizing a diagnosis for one or more conditions of the brain or spine. Such hypotheses may be generated by one or more hypothesis generating predictive models which are described hereinbelow.
(68) In one such predictive model, a prolonged bulbocavernosus reflex of more than 45 msec., such as is shown in
(69) Additionally, such a model (or another model) may also identify an abnormal BCR latency, wherein such latency (e.g., in a range of 50+ msec.) may be indicative of the following disorders: diabetic neuropathy, or other, neurogenic disease process.
(70) Moreover, such a model (or another model) may also provide output corresponding to an indication of a substantial absence or attenuation of the BCR within the predetermined sample time period for sampling the signals from the electrodes 2. In particular, such BCR absence or attenuation may be indicative of the following symptoms: sexual dysfunction, voiding dysfunction, and bowel dysfunction. Accordingly, the following may be considered likely diagnoses: decreased or absent sacral plexus response. Note that attenuation of the BCR in a graphical signature 68 also may be quantified as no bulbocavernosus response, particularly if such attenuation is below, e.g., a predetermined threshold such as a threshold corresponding to 2 micro volts above a baseline output from the muscle(s) at rest.
(71) There are numerous measurements related to the graph 62 that may be determined to be effective for predicting patient disorders (i.e., diagnosing a patient's symptom(s)), and various calibration or training processes may be used to determine the measurements that are most effective in providing an appropriate diagnosis. In addition to the measurements/characteristics of the BCR patient data received from the signal conversion process 48, some additional measurements that may be useful in diagnosing a patient's symptoms are: the integral of the graphical signature 68, the number or magnitude of local minima or maxima, an extent of the graphical signature 68 below/above a predetermined value, etc.
(72) In one embodiment of the presently disclosed system and method for screening, instead of (or in addition to) hypothesizing/diagnosing various disorders/symptoms, any of the above mentioned statistics or characteristics of the graphical signature 68 may be computed from the BCR digital data streams, and then output to a technician, nurse or physician for review and interpretation.
(73) In one embodiment of the screening system and method, one or more of the following assessments may be obtained from analysis of the BCR time series measurements generated by the signal conversion process 48:
(74) (a) the patient's spinal cord segments S2 through S4 are intact,
(75) (b) there may be lesions in the cauda equina,
(76) (c) an indication of actual chronic back pain, e.g., as asserted by the patient,
(77) (d) the latency between genital stimulation and the resulting bulbocavernosus reflexes are within a normal range and are not indicative of neurological order (e.g., contrary to what is asserted by the patient),
(78) (e) the latency between genital stimulation and the resulting bulbocavernosus reflexes are abnormal and are indicative of a neurological disorder,
(79) (f) the BCR time series measurement are indicative of a voiding dysfunction, bowel dysfunction, and/or
(80) (g) the time series measurements are indicative of a male impotence condition.
(81) A report may be generated by the analysis process 60, and the report can be included, e.g. printed, for entry into the patient's medical records, wherein the report may include any of the information disclosed hereinabove.
(82) Another embodiment of the probe is shown in
(83) One or more of
(84) (i) a handle 11a for holding the probe 10a,
(85) (ii) a piezoelectric disk 12a for at least detecting a mechanical pressure from the tip 34a for stimulating a patient's penis or clitoris in a similar manner as discussed hereinabove.
(86) (iii) a stimulus plunger 13a for transferring toward the piezoelectric disk 12a a resulting mechanical movement of the tip 34a contacting the patient's penis or clitoris; in particular, the plunger 13a includes the tip 34a, and an opposing end 30a,
(87) (iv) a plunger housing 14a which is operatively attached to an end of the handle 11a for retaining at least part of the stimulus plunger 13a therein; note that as with the plunger housing 14 of the probe 10, the plunger housing 14a includes an opening or bore 22a through which the shaft 18a of the stimulus plunger 13a extends, and the stimulus plunger 13a (as with the stimulus plunger 13) includes an expanded portion 24a that prevents the plunger from slipping entirely through the opening 22a,
(88) (v) a compression spring 15a for separating the stimulus plunger 13a from the piezoelectric disk 12a; in particular, the end 70 of the spring 15a fits onto an end 74 of the pressure transfer rod 78, and the spring end 82 contacts the opposing end 30a of the plunger 13a within the channel 84 extending the length of the handle 11a.
(89) When the probe 10a is fully assembled, the piezoelectric disk 12a is sandwiched between washers 86a,b (preferably plastic). The disk 12a and washers 86 are contained within an interior 90 of the piezohousing 94 which is secured to the end 98 of the handle 11a by, e.g., adhesive, mating threads, a snap fit, or another comparable securing mechanism. An endcap 102 seals the disk 12a and the washers 86a and 86b within the interior 90 by, e.g., snapping the semi-annular locking projections 106 onto the ridge or recess 110 adjacent the opening 114 of the interior 90. Additionally retained in the interior 90 is a tapered compression spring 118 which provides a pressure on the piezoelectric disk 12a at all times. When the pressure transfer rod 78 is positioned in the channel 84, the expanded head 122 rests against the center opening in the washer 86a, but the expanded head is too large to fit through this opening.
(90) During operation of the probe 10a, an operator activates the probe 10a by, e.g., a quick downward (preferably at least somewhat unanticipated) pressure of the stimulus tip 34a on the clitoris or penis. In one embodiment, when electrical power is already being supplied to the disk 12a from an electrical power source, e.g., a battery 17a (preferably positioned between the disk 12a and the washer 86b) within the handle 11a, or an exterior electrical power supply (not shown), such activation of the probe by contacting a patient's genital area causes the end 74 of the transfer rod 78 and the opposing end 30a to come in contact (or otherwise become configured for the transfer of tip 34a movement). Accordingly, the movement of the tip 34a toward the interior of the plunger housing 14a causes movement of the transfer rod 78 for increasing pressure on the disk 12a, wherein such increased pressure results in an additional electrical charge to develop on the surface of the piezoelectric disk. Since the disk 12a is electrically connected to the amplifier 36 (via a connection not shown, and the external conductor 38a), the electrical charge induced on the disk is detected by the amplifier for amplification. Thus, the disk 12a functions as a sensor for detecting contact between a patient and the tip 34a. However, note that alternative embodiments of sensors may be used to detect the transfer of pressure from the tip 34a to the disk 12a. In particular, the opposing end 30a may include a pressure sensitive switch (not shown) for detecting contact with the disk 12a.
(91) Alternatively, such activation of the probe 10a by contacting a patient's genital area may initiate an electrical current from a power source (e.g., a battery 17a, or an exterior electrical power supply) to the piezoelectric disk 12a thereby causing the disk to apply vibratory pressure to the transfer rod 78 for initiation of the BCR reflex. Thus, when the tip 34a is pressed against the penis or clitoris, the shaft 18a slides further into the plunger housing 14a and handle 11a for thereby compressing the spring 15a so that vibratory pressure from the disk 12a results in mechanical vibrations being transferred to the tip 34a (via the shaft 18a and the transfer rod 78) for stimulation of the penis or clitoris.
(92) As with the probe 10, at the time that the vibratory pressure commences to transfer to the tip 34a, a mechanical stress caused by the head 122 applying additional pressure against the disk 12a causes an electrical charge to develop on the surface of the disk. This electrical charge is communicated to the external conductor 38a via an internal conductor (not shown), and subsequently conveyed to the amplifier 36 (e.g., an EMG amplifier) where it is detected, and amplified as described hereinabove. The amplified signal is transmitted to the computer 40 (via transmission cable 44) as also described hereinabove.
(93) Accordingly, the probe (10 or 10a) at least provides electrical signals for identifying when to commence measuring an electrical response (via the sensing electrodes 2) to a BCR.
(94) In each of the above embodiments of the probe 10 and 10a, the included disk (or other vibration generating element) may be selected for generating vibrations having frequencies in the range of 2 Hz to 20 Hz, and more preferably in the range of 4 Hz to 10 Hz, most preferably approximately 5 Hz. In particular, the inventors have determined that vibrations outside of these ranges have reduced effect on the patient, and/or may be painful.
(95) Note that in addition to activation of the probe (10 or 10a) by contacting a patient's genital area, the probe may include an activation switch (e.g., button switch 124,
(96) Note that for embodiments of the probe wherein the included disk remains in a vibratory active state once the probe is powered on, such vibrations (or lack thereof) can be an indicator to an operator as to whether the probe has been previously used. For example, if upon activation of the activation switch, the operator senses no vibratory response from the disk 12 or 12a (e.g., due to a dead battery, and/or due to detection that the activation switch has been previously used to power the probe, etc.), then the operator will be alerted that the probe is at least non-functional and may have been used previously.
(97) Moreover, at least some embodiments, the probe (10 or 10a) may include a light emitting diode to notify an operator that the probe has not been previously used. For example, for a functional probe that had not been previously activated, such a diode would be activated when the button switch 124 is pressed for electrically activating the probe, and such a diode would emit light until a predetermined probe state occurs that deactivates the probe and prevents the probe from being reactivated.
(98) Embodiments of the probe (10 or 10a) may also prohibit their reuse based not only on an elapsed time, but also on the number of times the probe tip is depressed toward the interior of the probe housing. For example, by providing no more than, e.g., five probe tip depression within a predetermined maximal elapsed time of probe activation, additional assurance that the probe will not be reused with another patient can be provided.
(99) Referring now to
(100) (1) Description of the components shown in the embodiment of
(101) (1-1) A Bulbocavernosus Reflex Stimulation (BRS) External Power Supply 104 is a medical grade power supply that is used to supply 24-volt DC power to the BRS Module 108 (described hereinbelow).
(102) (1-2) A probe 10x is used to administer and measure the genital stimulation in a manner as described in previous embodiments hereinabove. The tip 34x in the probe 10x may be replaceable and may contain an ID chip 112. The ID chip 112 is used to prevent its tip 34x from being used more than once (e.g., prevented from being used on more than one patient) as is described further hereinbelow. Thus, instead of the entire probe 10x being non-reusable on different patients, only the probe tip 34x is non-reusable. The probe 10x interfaces to the BRS Module 108 (which includes an amplifier/filter 36x having substantially identical function to the combination of the SEMG 35 and the amplifier 36 disclosed in
(103) (1-3) The ID chip 112 provided in the probe tip 34x can output data to the BRS module 108 for determining whether the probe tip has been previously used to contact a patient, and if so, the elapsed time since this first use. In one embodiment, such data includes a time and date that the probe 10x was first activated, or if not previously used such data may include a predetermined value such as zero. Thus, the ID chip 112 includes a non-volatile data storage for storing data indicative of the probe tip's activation history (which may be only the initial date and time of, if any, the probe tip's first activation). In one embodiment, such activation history may include the time and date of each activation, and/or the elapsed time of each activation. Note that the ID chip 112 may be activated each time the probe 10x is operably connected to the BRS module 108. In particular, data is communicated on the conductors 160a and 160b from the MCU 128 processor (described below) for activating the ID chip 112 so that it will respond to the MCU with an acknowledgement of whether the probe tip 34x can or cannot be used for a subsequent patient contact. Accordingly, an acknowledgement by the ID chip 112 that the probe tip 34x cannot be used will cause the MCU 128 to issue commands to at least prevent data collection from the probe 10x, and preferably provide an indication to the operator that the probe having this tip cannot be used for such data collection. There are various ways to provide such an indication of probe non-use, e.g., visual display on the BRS module 108 may be used such as a red LCD may light when the probe cannot be used, and a green LCK may light when the probe can be used. Alternative/additional visual and/or auditory presentations are also within the scope of the present disclosure. Accordingly, iconic and/or textual information can be visually presented to an operator for indicating whether the probe 34x (with its current probe tip 34x) can be operably used. Alternatively and optionally, synthetic speech or various sounds may be used for indicating whether the probe 34x (with its current probe tip 34x) can be operably employed.
(104) (1-4) The BRS Module 108 is the interface unit between the BRS Computer 40x and both the patient applied probe 10x and EMG leads (collectively labeled as 46x in
(105) (1-4.1) Micro Controller Unit (MCU) 128.
(106) The MCU 128 is a microprocessor that controls and monitors data and communication in the BRS Module 108. The MCU 128 contains firmware for the following functions:
(107) a. Connects and communicates with the BRS computer 40x via the USB interface 132.
(108) b. Upon command the MCU 128, collects digital data from the surface EMG analog to digit converter 136 (which converts the amplified voltage differences from the electrodes 2 to digital data), and the Stim Probe analog to digital converter 140 (which converts the amplified probe activation signal to digital data). The MCU 128 then sends such digital data to the BRS computer 40x via the USB interface 132,
(109) c. Monitors the 24-volt power supply 104 and communicates the status of this power supply to the BRS computer 40x via the USB interface 132.
(110) d. Reads and updates the IC chip 112 in the Stim Probe Tip 34x to ensure that the Probe Tip is not used for more than 30 minutes.
(111) (1-4.2) Isolation DC/DC Converters 144.
(112) The Isolation DC/DC converters 144 supply isolated −3.3V, +3.3V, and 5V DC power to the patient connected components; in one embodiment such converters may be: a Datel UWR-5/2000-D24E-C Murata NDTD0503C or similar components as one of ordinary skill in the will understand.
(113) (1-4.3) Isolation Barrier 148.
(114) The Isolation Barrier 148 provides the necessary creepage and clearance distances between the AC mains connected power and patient connected power.
(115) (1-4.4) Power Detector 152.
(116) The power detector 152 is used by the microprocessor MCU 128 to monitor the state of the 24 Volt Power supply from the power supply 104.
(117) (1-4.5) Digital Optical Isolators 156.
(118) The Digital Optical Isolators 156 are used to provide isolation between the patient connected electronics (i.e., the electrodes 2 and 4), and USB powered electronics (i.e., the computer 40x). The optical isolators 156 allow the MCU 128 to communicate with the analog to digital converters 136 and 140, and the chip 112 in the Stim Probe Tip 34x via a one wire interface provided by the conductors 160a and 160b.
(119) (1-4.6) Stim Probe Amplifier/Filter 120.
(120) The Stim Probe Amplifier/Filter 120 amplifies and filters the signal from the Stim Probe 10x to a level that can be read by the A/D converter 140. The MCU 128 controls the analog to digital conversion process of the A/D converter 140.
(121) (1-4.7) Stim Probe A/D (Analog to Digital) Converter 140.
(122) The A/D converter 140 is an analog to digital converter for changing the incoming amplified Stim Probe 10x signal into a digital value for the MCU 128. to read and then send to the computer 40x for analysis. The MCU 128 controls the A/D conversion process of the A/D converter 140.
(123) (1-4.8) Surface EMG Amplifier/Filter 116.
(124) The Surface EMG Amplifier/Filter 116 amplifies and filters the voltage signals from the electrodes 2 to a level that can be read by the A/D converter 136.
(125) (1-4.9) Surface EMG A/D (Analog to Digital) Converter 136.
(126) The converter 136 is an analog to digital converter for changing the incoming amplified Surface EMG signal into a digital value for the MCU 128 to read and send to the computer 40x for analysis.
(127) (1-4.10) Signal Conditioner 164.
(128) The signal conditioner 164 translates the two wire interface 160a from the MCU 128 to/from the 1 wire interface 160b which communicates with the ID chip 112.
(129) (1-5) Computer 40x.
(130) The computer 40x provides a user interface for displaying, e.g., displays such as shown in
(131) a. Communicates and receives status information from the BRS Module 108 regarding power on (more generally activation status), information for obtaining probe tip ID chip 112 information (e.g., BCR time series values, ID chip status, etc.).
(132) b. Sends commands to the BRS Module 108 to acquire data from the Stim probe 10x.
(133) c. Graphs and/or analyses data from the Surface EMG data channel (which includes the components 116, 136, 156, and 128), and from the Stim Probe data channel (which includes the components 10x, 38x, 120, 140, 156, and 128) for presentation to an operator. The graphs and/or analysis performed may be as described hereinabove regarding the analysis process 60 (
(134) d. Processes the Stim probe 10x signal to determine the time of commencement of patient stimulation.
(135) e. Allows an operator to input patient and physician information.
(136) f. Stores test case data for later review and analysis.
(137) g. Prints reports is instructed by an operator.
(138) (1-6) Printer 168.
(139) The printer 168 is used by the Computer 40x to print reports on patient cases.
(140) (2) High Level Processing of Data in the BRS Module 108.
(141) For each of the EMG data channel (which includes the components 116, 136, 156, and 128), and the Stim Probe data channel (which includes the components 10x, 38x, 120, 140, 156, and 128) the high level algorithm used to process incoming analog data can be simplified down to:
(142) (a) first inputting the analog data to an amplifier and a high pass filter (provided by the components 116 and 120), followed by a RMS detector process (provided by the A/D converters 136 and 140), and
(143) (b) providing the output from (a) immediately above to a process (provided by the computer 40x), wherein the data is decimated down from a 2 KHz sample rate to a 1 KHz sample rate by simply saving every other sample.
(144) The signal provided by each of the above-identified channels passes through its own filter and RMS detector and decimator before being stored in the computer 40x (or a database operably connected thereto).
(145) (2-1) Implementation.
(146) Each high pass filter is implemented as a 4 pole Butterworth filter having a cutoff frequency of 10 Hz and a pass band ripple of 0%. Each RMS detector is implemented using the Root Mean Square algorithm for a finite number of sequential samples.
(147) (3) Filter Algorithm
(148) Each filter used in the amplifier/filter 36x may be a Chebyshev filter optimized for a pass band ripple of 0%, otherwise known as a Butterworth filter. Each of the filter is a form of recursive filter, which is also called an IIR (Infinite Impulse Response) filter. For a detailed description of recursive filters and the implementation see the Scientists and Engineers Guide to Digital Signal Processing chapters 19 and 20, by Steven W. Smith, published by California Technical Publishing.
(149) (3-1) Implementation.
(150) Each of the filters utilizes an embodiment of the following equation, as one of ordinary skill in the art will understand.
y[n]=a0x[n]+a1x[n−1]+a2x[n−2]+a3x[n−3]++anx[0]+b1x[n−1]+b2x[n−2]+b3x[n−3]+ . . . +bnx[0],
(151) wherein for 0≦i≦n, ai is the recursion coefficient of the incoming signal, bi is the recursion coefficient of previous output signals, x[i] is the incoming signal, and y[i] is the output signal.
(152) (4) RMS Algorithm
(153) The RMS (Root Mean Square) is a measure of the magnitude of a varying quantity (e.g., a signal), which is calculated for a series of discrete values for a continuously varying function. The BRS software uses the RMS algorithm to transform the incoming signals into a magnitude (as opposed to a wave) so that the analysis by an operator easier. The period of the function is configurable by the operator. For a more detailed description of the RMS algorithm see http://en.wikipedia.org/wiki/Root_mean square.
(154) (5) Stimulation Marker Detector Algorithm.
(155) The Stimulation Marker Detector algorithm scans the stimulation probe time series (received via the cable 38x) looking for a change in signal amplitude of 1%±0.1% within a 50-millisecond window. If/when a change in amplitude at t+50 that exceeds this threshold is detected, a marker is placed in the data stream of the Stim Probe data channel, wherein the marker corresponds to time t. If a marker is detected, this algorithm is blacked out for a period of 1.5 seconds.
(156) (5-1) Implementation
(157) For each sample in the time-record (minus 50 mS) perform the following steps:
(158) (5-1.1) Scan ahead of current position up to 50 mS;
(159) (5-1.2) If the magnitude of the stimulus signal meets criteria, place a marker in the data stream of the Stim Probe data channel;
(160) (5-1.3) Black out additional marker placement for 1.5 seconds
(161) From the disclosure hereinabove, and the accompanying figures, it is believed that one of ordinary skill could manufacture the present screening system, and in particular, the probe (10 and/or 10a). More particularly,
(162) Other embodiments of the probe are shown in
(163) Since the electrodes 172 may be fixedly attached to the tip 34b, and this tip fixedly attached to the probe handle 11b, the probe 10b of
(164) Embodiments of the probe 10b may be configured with various parameters. For example, the electrodes 172 may be spaced apart in a range of 1/16 of an inch to 7/16 of an inch. Additionally, the voltage difference between the electrodes 172 may be in the range of 0.25 Volts to 1.0 Volt, and more preferably from 0.3 Volts to 0.7 Volts. Note that any leakage of current from one of the electrodes 172 to the sensing electrodes 2 can be compensated for.
(165) In the embodiment of
(166) Note that the cap 176 may be secured to the embodiment of the probe 10b (e.g., as shown in
(167) In one embodiment of the cap 176, a cap stabilizer 198 may include an ID chip 112 as described hereinabove. In particular, the ID chip 112 can be in signal communication with an electrical fitting 199 for communicating with the BRS module 108 as described hereinabove.
(168)
(169) During operation of the probe 10c with the cap 176c operably attached thereto as in
(170) In another embodiment of the cap 176c may include a flat spring 220c provided along the shaft 188c as shown in
(171) Another embodiment of the probe (10d) and corresponding cap (176d) is shown in
(172) During operation of the probe 10d with the cap 176d operably attached thereto as in
(173) The invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein. It is apparent to those skilled in the art, however, that many changes, variations, modifications, other uses, and applications of the invention are possible, and also changes, variations, modifications, other uses, and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention, which is limited only by the claims which follow.
(174) The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. In the foregoing Detailed Description of Certain Embodiments of the Invention, for example, various features of the invention are grouped together in one or more embodiments for the purpose of streamlining the disclosure. The features of the embodiments of the invention may be combined in alternate embodiments other than those discussed above. This method of disclosure 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 following claims are hereby incorporated into this Detailed Description of Certain Embodiments of the Invention, with each claim standing on its own as a separate preferred embodiment of the invention.
(175) Moreover, though the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations, combinations, and modifications are within the scope of the invention, e.g. as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable, and/or equivalent structures, functions, ranges, or steps to those claimed, whether or not such alternate, interchangeable, and/or equivalent structures, functions, ranges, or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.