U.S. patent number 3,850,161 [Application Number 05/348,864] was granted by the patent office on 1974-11-26 for method and apparatus for monitoring and counteracting excess brain electrical energy to prevent epileptic seizures and the like.
Invention is credited to Saul Liss.
United States Patent |
3,850,161 |
Liss |
November 26, 1974 |
METHOD AND APPARATUS FOR MONITORING AND COUNTERACTING EXCESS BRAIN
ELECTRICAL ENERGY TO PREVENT EPILEPTIC SEIZURES AND THE LIKE
Abstract
This invention pertains to a biomedical detecting and control
apparatus wherein electrical signals in the brain of mammals are
continuously monitored by electrodes implanted in certain critical
places in the brain wherein excess electrical energy is manifest
during epileptic seizure conditions as well as during psychic
storms of some types of mental illness. Such signals are processed
via electrical systems of various circuits for inversion,
comparison, vector analog addition, filtering, modulation, level
set, safety level limits and self test to provide a controlled
signal output which automatically reduces or eliminates the excess
electrical energy at the point of detection. The points of
detection and control may be, but do not have to be, the same spots
on the brain. The probes may be near the surface of the brain or
deep set in the brain depending upon the area affected. In addition
to the method, there is described an electronic device which is
contemplated to be housed in a small housing outside the body of
the mammal and connected through wire conductors connected to the
electrodes at the point of detection and at the other end of the
conductors to outlet connectors in the housing providing the point
of control.
Inventors: |
Liss; Saul (Paterson, NJ) |
Family
ID: |
23369877 |
Appl.
No.: |
05/348,864 |
Filed: |
April 9, 1973 |
Current U.S.
Class: |
600/544; 607/45;
607/68; 607/63 |
Current CPC
Class: |
A61B
5/369 (20210101); A61B 5/4094 (20130101) |
Current International
Class: |
A61B
5/0476 (20060101); A61b 005/04 (); A61n
001/00 () |
Field of
Search: |
;128/2.1R,2.1B,2.1P,2.1Z,2.6D,419R,419S,422,1C,410 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
John Osmundson, "Matador with Radio Stops Wired Bull" New York
Times Newspaper, pg. 1 & 20, 5-17-65..
|
Primary Examiner: Gaudet; Richard A.
Assistant Examiner: Cohen; Lee S.
Attorney, Agent or Firm: Roberts; Ralph R.
Claims
What is claimed is:
1. Apparatus for monitoring, analyzing and when required
counteracting excess brain electrical energy of a patient to
prevent epileptic seizures and the like, said apparatus including:
(a) three electrodes adapted to be implanted in the brain being
monitored, each electrode connected through conductors to a
constantly energized and connected electronic circuit, said
electrodes including a first implantable electrode adapted to be
placed in a zero activity point of the brain, the electrical output
from this first electrode detecting the levels of normal and
abnormal electrical energy and feeding this output as a signal to
the electronics circuit portion of the apparatus, a second
implantable electrode adapted to be placed in a typical point of
detection area of the brain, the output from this electrode sent as
a signal from this area to the electronic circuit, and a third
implantable electrode adapted to be placed in a typical point of
control of the same brain, this electrode receiving countermotive
forces from the electronic circuit when said circuit so determines;
(b) an electronic means and an amplifier means in said electronic
circuit, said electronic means receiving the output of the
implantable second electrode and inverting this output after which
the resulting electrical signal is fed to said amplifier means of
the electronic circuit, said amplifier means providing a comparison
and addition means to incoming signals; (c) a conductor connected
to the first electrode, said conductor being connected to said
amplifier means and carrying the electrical energy level of the
zero activity portion of the brain to the amplifier which analyzes
and compares this energy level in relation to previously
established normal; (d) means for sending a reference voltage to
the amplifier comparison and addition circuit, this reference
voltage established and set by the operator in accordance to
previously determined electrical thresholds of the brain of the
patient in which the electrodes are to be implanted, this reference
voltage being compared by and in said amplifier circuit and where
necessary a vector addition is made by this amplifier circuit to
add voltage to the inverted received voltage; (e) a circuit means
in the electronic circuit for receiving and monitoring the signal
from the comparison and addition circuit means and when this signal
exceeds a set level amplifies this signal a determined amount; (f)
a circuit means providing both passive and active electronic
network means for receiving the monitored and amplified signal
indicative of excess energy outputs from the second electrode and
within predetermined maximum limits provides a countermotive force
which is sent through a conductor to the third electrode which
force quells this storm in the brain, and (g) a power means
connected to the electrical circuit to supply a constantly "on"
power necessary to energize the electrical circuit to normal
operating levels.
2. Apparatus for monitoring and counteracting excess brain
electrical energy as in claim 1 in which the power means is a
battery whose energy level is monitored by a self test circuit
means and there is additionally circuit means connected to said
power means providing a limit control and an alarm which is
actuated when the voltage drops below that set by the limit
control.
3. Apparatus for monitoring and counteracting excess brain
electrical energy as in claim 2 in which there is provided an
oscillator which generates a high frequency signal connected to the
circuit means for receiving and monitoring the signal from the
comparison and addition circuit, this high frequency signal being
used as a carrier for a feedback signal when such a signal is sent
to the third electrode.
4. Apparatus for monitoring and counteracting excess brain
electrical energy as in claim 3 in which the electronic circuit
includes a filter connected between said comparison and analog
addition means and said circuit means for receiving and monitoring
the signal from the comparison and analog addition means which
receives the signal output from electronic circuit means providing
the comparison and analog addition function and filters the
electronic flow to prevent this flow from interfering with other
electrical brain functions such as heart beat and respiration, said
filtered signal being conducted and fed to the circuit means for
receiving and monitoring the signal from the comparison and
addition circuit means.
5. Apparatus for monitoring and counteracting excess brain
electrical energy as in claim 4 in which the electrodes are adapted
to be permanently implanted and the electronics and battery
therefore are encased so as to provide a small size unit which may
be easily carried on and by the body of the one being
monitored.
6. A method for monitoring and counteracting excess brain
electrical energy to prevent epileptic seizures which includes the
steps of: (a) implanting three electrodes in the brain of the
mammal being monitored, the first electrode being placed in a zero
activity point of the brain and from this electrode feeding its
electrical output to a constantly energized and connected
electronic circuit, the second electrode being placed in a typical
point of detection area of the brain and a third electrode being
placed in a typical point of control of the same brain; (b)
connecting the electronic circuit to the second electrode by a
conductor and inverting electronically the output of the brain from
this second electrode and feeding the resulting inverted signal to
an electronic means in said circuit to provide a comparison and
addition means to incoming signals; (c) connecting a conductor to
the first electrode which carries the electrical energy level of
the zero activity in the brain, this electrical energy being fed to
the comparison circuit for analysis of the energy in relation to a
normal energy level; (d) setting by the one in charge of the
apparatus a reference voltage control level, this reference voltage
being fed to the electronic means providing the comparison, said
means performing vector addition when necessary; (e) feeding the
output signal current of the addition means to a level set
amplifier portion of the electronic circuit, which, when necessary,
amplifies this current signal; (f) sending the signal from the
level set amplifier to a safety limit circuit portion of the
electronic circuit, this portion providing passive and active
electronic networks which receive this signal and in the cases of
excessive energy outputs from the second electrode and the
comparison circuit feeds a countermotive force to the third
electrode to quell an anticipated storm in the brain, and (g)
providing a power means which enables the electronic circuit
portion of the apparatus to be constantly energized.
7. The method for monitoring and counteracting excess brain
electrical energy as in claim 6 in which the step of providing the
power means is a battery whose energy level is monitored by a
self-test circuit having a low voltage limit control and an
alarm.
8. The method for monitoring and counteracting excess brain
electrical energy as in claim 7 which includes the further step of
connecting an oscillator which generates a high frequency signal so
as to feed said oscillating signal to the level set amplifier
portion of the electronic circuit with this high frequency signal
providing a carrier for the feedback signal to the third
electrode.
9. The method for monitoring and counteracting excess brain
electrical energy as in claim 8 which includes the step of
providing a filter which receives the signal output from the
electronic means providing the comparison and analog addition and
filters the electronic current therefrom to prevent this current
signal from interfering with other electrical brain functions such
as the heart beat and respiration and feeding said filtered signal
to the level set amplifier portion of the electronic circuit.
10. The method for monitoring and counteracting excess brain
electrical energy as in claim 9 which includes permanently
implanting the electrodes and further includes encasing the
electronics and battery to provide a small unit which may be easily
carried on the body of the one monitored.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
With reference to the classification of art as established in the
U.S. Patent Office the present invention pertains to art found in
the Class entitled, "Surgery" (Class 128) and the subclass of
"pulsating and alternating electric circuits" (subclass 421).
2. Description of the Prior Art
Many patents are directed toward analysis of and conditions causing
mental illness. These studies of mammal brains and the resulting
behaviors have confirmed that electrical impulses within the brain
cause predicted results in parts of the body associated with
specific areas of the brain. Among these patents are U.S. Pat. No.
3,495,596 to CONDICT as issued on Feb. 17, 1970; U.S. Pat. No.
2,368,207 to EATON as issued on Jan. 30, 1945 and U.S. Pat. No.
2,473,378 to LIBERSON as issued on June 14, 1949.
As a result of these studies of mammals, including humans, it has
been found that there are certain types of epilepsy and psychic
diseases (mental illness) wherein an aura condition exists prior to
the happening of an epileptic or psychic storm. During that period
of time it has been found that the level of electrical activity
rises by a magnitude of 5 to 10 times the normal 10 millivolt level
typically found in the average human brain. The frequency of the
brain signals change from 5 to 8 herz down to one-half to one herz.
During this storm period in particular areas of the brain, the
pattern of electrical activity or irregularity can spread to other
various spots and areas of the brain much in the way worn
electrical insulation may give way to excess electrical potential
causing an electrical discharge either locally or in large areas
depending on the specific characteristics of insulation and voltage
application. Just as electrical systems of extreme precision are
protected and controlled by regulators, filters, fuses, etc. so
also is it a purpose of this device to counteract automatically any
excess electrical energy in the brain at the spots being monitored
and detected.
Cases have been reported wherein olfactory senses have been
utilized to overcome the aura effect and by this means prevent the
consequential seizure. This has produced a belief that, at least in
some cases, the electrical energy in the brain indicated by such
reaction can be duplicated under controlled conditions and can be
used to control a brain center other than at the place at which the
excessive aberrant energy is resent. Hence, the method and present.
of this invention contemplates conditions where implanted
electrodes for detection and control may be placed in selected
parts of the brain not directly involved with the excessive
pattern.
Temporal lobe epilepsy is a typical disease where it is believed to
be necessary to provide deep implanted electrodes; first of all to
detect the electrical presence of the aberrant energy and second of
all to counteract locally this excessive aberrant energy. The
method and apparatus of this invention is intended to provide the
detection means and the electrical signals necessary to counteract
and restrain these excesses.
SUMMARY OF THE INVENTION
This invention may be summarized at least in part with reference to
its objects. It is an object of this invention to provide both the
method and the means of monitoring the brain of a mammal by means
of permanently inserted electrodes in selected critical areas of
the brain. By connecting these electrodes to a monitoring device,
safety limits for brain signal outputs can be evaluated and upon
indications of excess outputs counteracting signals can be fed to
the brain to prevent aberrant activity as produced in certain
mental illness conditions and epilepsy seizures.
In addition to the above summary the following disclosure is
detailed to insure adequacy and aid in understanding of the
invention. This disclosure, however, is not intended to prejudice
that purpose of a patent which is to cover each new inventive
concept therein no matter how it may later be disguised by
variations in form or additions of further improvements. For this
reason there has been chosen a specific circuit diagram showing a
means of employing the signals within a brain of a mammal and by
monitoring and counteracting excessive energy showing a preferred
means for preventing these excesses. This specific embodiment has
been chosen for the purposes of illustration and description as
shown in the accompanying drawings wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 represents a block diagram showing the principal operation
of the apparatus;
FIG. 2 represents a pictorial representation of a human brain and
the typical implanting of three electrodes for control of epileptic
seizure conditions, and
FIG. 3 represents a diagram showing the attachment of and the
support of the apparatus to and by a human.
In the following description and in the claims various details will
be identified by specific names for convenience, these names,
however, are intended to be generic in their application.
Corresponding reference characters refer to like members throughout
the three figures of the drawings.
The drawings accompanying, and forming part of, this specification
disclose certain details for the purpose of explanation of the
broader aspects of the invention, but it should be understood that
details may be modified without departure from the concept of the
invention and that the invention may be incorporated in other
structural forms than shown.
PRINCIPLE OF OPERATION AS SEEN IN THE ASSOCIATED BLOCK DIAGRAM
In the skull or head 10 of the mammal a common electrode 12 is
placed into the frontal bone or other zero level activity point
from which to detect levels of normal and abnormal electrical
energy created in the brain. This electrode is connected by a
conductor 13 to an electronic circuit.
The second detecting electrode 14 is placed into one of the
critical brain areas such as the eleptogenic lesion portions of the
skull 10, while a third electrode 16 is placed into a control point
of the brain. This may be in the same area as the detecting
electrode or a different area of the brain.
Signals from electrode 14 are fed through a conductor 20 to an
inverting electronic device 22 which changes the electrical phase
of the detected signal in preparation for use by a comparison
circuit 24. The signal from the inverter 22 is fed to the
comparison circuit through a conductor 26.
A reference voltage level R, which typically may be about 10
millivolts in the case of a human, is set by the doctor in charge
who has determined by appropriate tests the level of voltage in the
brain beyond which the patient to which the device is affixed needs
a countermotive force brought to action to quell the ensuing
anticipated storm. This reference voltage after the level has been
established is set and then is fed to the comparison circuit 24
through a conductor 28.
The comparison and analog addition circuit 24 will perform a vector
addition so that the resultant R-X should be a quantity negative in
phase to that of the original detected value X from electrode 14.
The resultant is such that X+(R-X) equals the value R, the normal
set level. However, it may be found that the point of control as
compared to the point of detection may be scale factors apart. When
this occurs a level set amplifier 30 provides compensation for such
a condition.
Between the output from comparison circuit 24 which is fed to
amplifier 30 is a filter 32 which receives the output (R-X) from
circuit 24 as fed through conductor 34. This filter 32 is used to
prevent the electronics of the brain analysis from interfering with
other electrical functions such as heart beat and respiration. An
oscillator 40 is adapted to generate a high frequency signal which
signal is used as a carrier for the feedback information being
communicated to the brain point of control.
Since the synaptic chains (in the brain) have the manifestation of
semiconductors in that they act as diode detectors as in a radio
circuit the information provided to the snyaptic circuits is
oriented in such a manner that the normal operation of the nervous
system will now detect the control data at minimum energy level to
accomplish the needed reduction of the brain energy at the
localized areas and provide an elimination of the excess electrical
energy in the brain.
Signals from the modulator 30 are sent through conductor 42 to a
safety limit circuit 44 which provides standby passive and active
networks which act as a limiting fuse to insure and prevent any
excessive energy from the said electrical apparatus to be fed to
the brain to cause or affect the brain or other nervous system.
Signals from the circuit 44 to electrode 16 is carried by conductor
46. A battery power supply 50 energizes the circuit and because of
the serious nature of this control device and what a deficiency in
energization would cause preferably includes a self test circuit
with a low limit control 54 and an alarm 56 for extra
protection.
Referring next to FIG. 3, there is depicted the normal arrangement
and mounting of the apparatus on the patient. The electrodes 12, 14
and 16 are implanted in the brain in the skull 10 of the patient 60
to be treated and controlled. Conductors 13, 20 and 46 carry the
signals and controlling voltage to the electronic circuits carried
in a small case 62. The components carried by the case are enclosed
in phantom outline in FIG. 1. Except for the battery power which is
contemplated to be a small battery, the circuits providing the
inverter 22, the comparison and analog addition 24, filter 32,
modulator 30, safety circuit 44, oscillator 40 and self test
circuit 54 are all contemplated to be solid state minaturized as
much as possible. The reference voltage set is usually an
adjustable resistor located within the case and set by key means to
prevent an accidental change. It is contemplated that the case 62
when used externally is less than the size of a package of
cigarettes. With integrated circuitry the case 62 may be made even
smaller for implanting under the skin of the patient 60.
USE AND OPERATION
Automatic feedback control is the essence of this invention in that
this control receives signals indicating aberrant energy from the
brain, analyses it electronically as necessary and with a proper
safety and power supply means then feeds electric energy back into
the brain in opposition to the original aberrant level so that the
net resultant voltage, current and/or electrical field in localized
areas on the brain is maintained at no level greater than that
experienced during normal behavior. The electronic feedback device
of this invention is applied not only to those types of epilepsy
where aura is electrically seen prior to an actual seizure
(typified by some types of Grand Mal and Temporal Lobe Epilepsy)
but also is applied to some types of mental illness where psychic
storms occur providing electrical activity in the brain similar to
that of epilepsy but having as its manifestations psychic storms
instead of physiological seizures.
The means of detecting and controlling the voltage level of the
brain is through the use of implanted electrodes 12, 14 and 16. The
reason for employing implanted electrodes as compared to surface
electrodes is to provide the exact point of application in the
brain where either the point of detection or the point of control
can be found without having the electrical path through the skull
either deterioriate the signal in terms of the detection signal due
to the impedance of the fluids, tissue, skull bone and other media
between such point of detection and an external point. Similarly, a
control signal for feedback data, if applied externally, would
require a larger electrical signal to produce a comparable control.
Typical electrical voltages represented in medical research studies
reveal that when monitored internally a normal brain pattern signal
can reach 10 millivolts while the same signal monitored outside the
skull produces a level of approximately 10 microvolts.
The aura condition of an epileptic seizure can in fact increase the
electrical activity a factor of 10 times to a level 100 millivolts
(when monitored internally). Hence, for a corrective signal to be
applied in opposition to such an aberrant level, a minus 90
millivolts level would be internally applied whereas approximately
minus 90 volts would be externally applied; a quantity which could
be dangerous. Therefore, in the present invention internal
electrodes are to be used so that the voltage control will be at
low levels which is safe.
The concept of automatic feedback has been used in the field of
servo technology for many years. The uniqueness of the present
invention is the application of automatic feedback theory and
devices wherein the electrical energy of a mammal such as a human
is considered part of a servo loop in the automatic feedback. The
normalizing of this current flow provides a resultant improvement
in the mammal's performance where without such feedback control
afflictions such as epilepsy and mental illness prevent the normal
behavior of that particular mammal and the resulting deterioration
caused by the affliction.
The employment of this system requires implanted electrodes,
transdermal wires and external electronics. It is noted that just
as history with heart pacemakers has shown that totally implanted
devices can be made practical, so also is it anticipated that this
device with sufficient experience and history will be implanted
with the application of electronic miniaturization. The miniature
electronic detection and control device of this invention will be
capable of being totally implanted thus eliminating transdermal
wire with the inherent possibility of damage and failure of the
system.
In use, detected signal from electrode 14 is carried by conductor
20 to an inverting circuit 22 where the signal is reversed in
polarity (minus the reference voltage level) in order to be added
to the aberrant brain electrical level during the epileptic or
psychic storms. This causes the brain voltage to be reduced to that
of the reference level. This action is similar to that of adding
several voltages together in an analog computer at a "summing
junction" where the resultant electrical levels are the algebraic
sum of all voltages added at that point. This, of course, takes
into consideration the sign or phase of the voltages being
added.
The "common" or "ground" electrode 12 is used as a reference point
against which the electrical levels at the point of detection, the
point of control and all other computing reference and safety
electrical levels is judged and conditioned.
The inverted signal -X from circuit 22 is carried by conductor 26
to the comparison and analog addition circuit 24. Also to
electronic circuit 24 is fed signal R which is carried by conductor
28 and is the reference voltage level set by the doctor. Another
signal is the brain signal from the "common" electrode 12 which is
fed to this comparison circuit. Direct current power to operate the
electronic circuitry is derived from the power supply 50 which has
its own related safety and self-test circuitry 54 which when used
as a permanently installed unit includes a low limit alarm 56 which
indicates when a malfunction or voltage loss occurs.
The comparison and analog addition circuitry 24 receives the
inverted signal -X from conductor 26 and combines this
algebraically with signal R carried by conductor 28 so that the
electrical quantity R-X is produced as a raw signal yet to be
conditioned for use as the ultimate feedback signal. This raw
signal is fed by conductor 34 to the filter 32 which removes all
frequency components which could effect vital functions such as
respiration and heart action. The frequency band usable for these
functions is approximately 5 to 40 herz. The signal entering the
modulation and level set amplifier 30 is the electrical quantity
R-X limited within the frequencies of F to F2 (approximately 5 to
10 herz).
The oscillator 40 and modulator level set amplifier 30 are both
operated from the same battery power supply 50, noted above.
The oscillator generates a high frequency carrier signal wherein
there is created a selected frequency having a range from 40,000
herz to 1 million herz. The need to use a high frequency carrier is
so as to utilize the lowest voltage possible in the carrier
electrical signals and also to utilize the inherent electrical
phenomenon manifest in the synapsis of the brain. Since the
electrical nerve pathways in the body are really composed of
synapsis which react to provide electrical energy transfer similar
to the semiconductor devices called diodes the operator of the
device is able to forecast the utilization of these synaptic
pathways as diode detectors. This means that the diode
characteristic which is used in radio circuits to separate the
audio information from the high frequency carrier signal is like
the present circuit of this invention where it is planned to use
the conditioned feedback signal to detect and provide for brain
control utilizing the brain synapsis. The brain synapsis is emloyed
to demodulate the correct data from the high frequency carrier
which by itself is not seen by the rest of the body. The level set
amplifier 30 is set by the doctor so that the particular mammal
being treated has the determined electrical levels set to
compensate for the particular levels required to stablize the brain
activity of that mammal. If the control signal is fed back into the
same area from which the electrode received signals are set, the
voltage is likely to be at unity value with respect to the
originating signal. However, when it is necessary to apply the
control signal at a point of control which is different from the
point of detection by the electrodes it will be required to use a
ratio scale to increase or decrease the control signal
experimentally to determine that signal level necessary at the
point of control which is required to quell or stabilize the
detected aberrant energy in the brain.
The modulator 30 receives the high frequency signal generated by
the oscillator 40 and impinges on the signal the envelope of
frequencies entering the modulator and level set amplifier 30.
These frequencies include the electrical signal quantity R-X
filtered from F1 to F2 by filter 32 which modulates in amplitude
the high frequency signal. The resulting conditioned electrical
signal is sent by conductor 42 to the safety limit circuit 44.
This safety limit circuit 44 provides additional electrical
safeguards to prevent either momentary or long term pulses or
continuous electrical signals from developing to a level which will
be injurious to the mammal involved. As the time constant of energy
of the physiological mammal is in terms of milliseconds and the
electrical condition and functioning of the control circuit is in
terms of microseconds, the electronic circuit acts at a rate which
is responsive and available to assist the physiological needs of
the mammal.
Self-test circuit 54 is designed to assure the mammal, when human,
to which this device is connected that the electronic circuit is in
an operative condition ready for activiation without any jeopardy
of the operation arising from low battery voltage.
It is anticipated, as above noted, that the initial electronics and
power source (battery and control safety circuits) will occupy a
volume less than a pack of standard cigarettes and be externally
carried on the user. With the use of micro electronics it is
further anticipated that this size can ultimately be further
reduced and the electronics and power source be mounted beneath the
skin surface of the user in the form of a small wafer.
Terms such as "left," "right," "up," "down," "bottom," "top,"
"front," "back," "in," "out" and the like are applicable to the
embodiment shown and described in conjunction with the drawings.
These terms are merely for the purpose of description and do not
necessarily apply to the position in which the apparatus for
monitoring and counteracting excess brain energy may be constructed
or used.
While this particular embodiment of the apparatus and method of use
has been shown and described it is to be understood the invention
is not limited thereto since modifications may be made within the
scope of the accompanying claims and protection is sought to the
broadest extent the prior art allows.
* * * * *