Sábado 26 Maio 2018

Transcranial Direct Current Stimulation ( tDCS )

Transcranial Direct Current Stimulation ( tDCS )

Aline Patrícia Brietzke

The Transcranial Direct Current Stimulation is a noninvasive brain stimulation technique of low cost, easy to use and transport. Its function is based on the change of the resting potential of the neuronal membrane to induce changes in cortical excitability. Moreover, it has low adverse effects related - itching, tingling, cefeleia, burning. The material consists of an apparatus, two batteries, two electrodes (anode and cathode), two sponges and saline (Figure). These electrodes arranged in different assemblies in the scalp, creating a continuous flow of electric current and low intensity reaches a certain region of the cerebral cortex causing modulation according to polarity. The anodal stimulation induces depolarization of the neuronal membrane, facilitating neuronal firing. While cathodal stimulation has the opposite effect. That is, because the cathode hyperpolarization the neuronal membrane. You can also perform sham stimulation (sham). In this case the device performs a ramp until reaching the current intensity required, but then the current is gradually reduced until the device is turned off. The effects are perceived by the volunteer, but no active stimulation. Currently its use is mainly in the rehabilitation of chronic cognitive functions, treatment of patients with mood disorders, and acute pain.

 

Figure - Illustration of tDCS device on the scalp. In this case anodal stimulation.

 

Projects & Pain Neuromodulation Group linked to technique:

A) Effect of stimulation and transcranial direct current eletrocacumpultura in pain, functional ability and cortical excitability in patients with osteoarthritis

B) Study of the Brain by optical functional neuroimaging in patients with chronic pain by using psychotropic stimulation and transcranial

C) Studying the brain by optical functional neuroimaging in fibromyalgia patients using transcranial direct current stimulation

D) Effect of transcranial direct current stimulation in chronic pain associated with endometriosis

E) Evaluation of the potentiated effect of transcranial direct current stimulation of opioid analgesia on pain thresholds in humans

F) Analysis of attentional capacity fribromialgia patients undergoing intervention with tDCS : randomized, blind, crossover , controlled - Sham tDCS

G) Development of apparatus Transcranial direct current stimulation for home use


 

Quantitative sensory / Algometry / modulation test test Guests pain

Aline Patrícia Brietzke

Quantitative sensory testing (QST) is a simple method to evaluate the sensing thresholds forward to a controlled stimulus intensity assessing coarse and fine fibers. The apparatus consists of a 30x30 mm2 termodo with thermal stimulus of 1 ° C / s (Figure 1). It is the best method to detect, characterize and quantify sensory changes, hipoestasia and hypoalgesia to heat and cold, and so is useful for both epidemiological studies and controlled clinical trials. It's a simple, not painful, easy to understand method, used primarily to monitor the progression of disease, evaluate therapeutic responses, locks and evaluation of patients with neuropathy have loss or increased skin sensitivity.

 

Figure 1 - Test Sensitive Quantification. Termodo placed on the inner side of the forearm

Algometry pressure is a technique that aims to quantify the ability of perception and pain tolerance by physical stimuli (pressure on nociceptors). At the end of the device there is a round tip diameter of 1 cm is placed on the skin (Figure 2). Applies direct pressure to the pain start, measured in kilogram - force. The sites to perform the technique may vary according to the study protocol. Some of these locations may be: inside of the forearm and thigh and masseter muscle. According to the degree of myelination, neurotransmitters have different driving characteristics, thereby producing different clinical patterns. The perception threshold and pain tolerance of a certain neurotransmitter associated with the ability to capture nociceptive, upper and indirectly related to the excitatory controls superior inhibitory controls. When subliminal stimuli produce pain sensation (allodynia) or when the individual has reduced tolerance to painful stimuli ( hyperalgesia ) featuring break this harmony.

 

Figure 2 - pressure algometer

 

Conditional pain modulation test (CPM) is the brain's ability to regulate the experience of pain. It is a scientific test to investigate the endogenous analgesic way of this adjustment. A pain is produced by a stimulus (conditioning) into a body part. This pain is reduced by a concurrent other pain stimulus, that is, a second test in a distant part of the body. Is usually performed along with QST. One arm is held the QST and other CPM. CPM is accomplished by immersing the hand contralateral to the pain stimulus by QST in a bottle with cold water (Figure 3). The effect of reduced CPM is the evaluation of the first sensation of pain by the second stimulus of the test, also described as " pain inhibiting pain”. The Low CPM efficiency indicates a low capacity to inhibit endogenous pain through body systems. This fact is associated with various pain syndromes, including temporomandibular disorders, fibromyalgia and headache, chronic and neuropathic pain.

 

Figure 3 - Test conditioned pain modulation. QST and right arm with his left hand in cold water. Asks the individual to pay attention to the sensation of heat caused by QST while the left hand is in cold water. The purpose of the test is to make the brain divert attention from the painful sensation caused by heat and concentrate in cold water. But the individual must pay attention to the feeling of heat. CPM may also be carried out with cold water and algometry.

 

Projects & Pain Neuromodulation Group linked techniques:

A) Effect of stimulation and transcranial direct current eletrocacumpultura in pain, functional ability and cortical excitability in patients with osteoarthritis.

B) Study of the Brain by optical functional neuroimaging in patients with chronic pain by using psychotropic stimulation and transcranial

C) Studying the brain by optical functional neuroimaging in fibromyalgia patients using transcranial direct current stimulation.

D) Analysis of attentional capacity fribromialgia patients undergoing intervention with tDCS: randomized, blind, crossover, controlled-Sham tDCS.

E) Effect of transcranial magnetic stimulation on cortical, subcortical neuromodulation and pain thresholds in patients with chronic myofascial pain

 


 

Validated scales by Pain&Neuromodulation Group

 

A - Validation of the Pain Catastrophizing Scale

B - Validation of Brazilian quantitative sensory testing (QST) Device

C - Validation of the Functional Pain Scale

D - Validation of the State-Trait Anxiety STAI Scale.

 


Transcranial Direct Current Stimulation ( tDCS )

Aline Patrícia Brietzke

The Transcranial Direct Current Stimulation is a noninvasive brain stimulation technique of low cost, easy to use and transport. Its function is based on the change of the resting potential of the neuronal membrane to induce changes in cortical excitability. Moreover, it has low adverse effects related - itching, tingling, cefeleia, burning. The material consists of an apparatus, two batteries, two electrodes (anode and cathode), two sponges and saline (Figure). These electrodes arranged in different assemblies in the scalp, creating a continuous flow of electric current and low intensity reaches a certain region of the cerebral cortex causing modulation according to polarity. The anodal stimulation induces depolarization of the neuronal membrane, facilitating neuronal firing. While cathodal stimulation has the opposite effect. That is, because the cathode hyperpolarization the neuronal membrane. You can also perform sham stimulation (sham). In this case the device performs a ramp until reaching the current intensity required, but then the current is gradually reduced until the device is turned off. The effects are perceived by the volunteer, but no active stimulation. Currently its use is mainly in the rehabilitation of chronic cognitive functions, treatment of patients with mood disorders, and acute pain.

 

Figure - Illustration of tDCS device on the scalp. In this case anodal stimulation.

 

Projects & Pain Neuromodulation Group linked to technique:

A) Effect of stimulation and transcranial direct current eletrocacumpultura in pain, functional ability and cortical excitability in patients with osteoarthritis

B) Study of the Brain by optical functional neuroimaging in patients with chronic pain by using psychotropic stimulation and transcranial

C) Studying the brain by optical functional neuroimaging in fibromyalgia patients using transcranial direct current stimulation

D) Effect of transcranial direct current stimulation in chronic pain associated with endometriosis

E) Evaluation of the potentiated effect of transcranial direct current stimulation of opioid analgesia on pain thresholds in humans

F) Analysis of attentional capacity fribromialgia patients undergoing intervention with tDCS : randomized, blind, crossover , controlled - Sham tDCS

G) Development of apparatus Transcranial direct current stimulation for home use

 


 

Quantitative sensory / Algometry / modulation test test Guests pain

Aline Patrícia Brietzke

Quantitative sensory testing (QST) is a simple method to evaluate the sensing thresholds forward to a controlled stimulus intensity assessing coarse and fine fibers. The apparatus consists of a 30x30 mm2 termodo with thermal stimulus of 1 ° C / s (Figure 1). It is the best method to detect, characterize and quantify sensory changes, hipoestasia and hypoalgesia to heat and cold, and so is useful for both epidemiological studies and controlled clinical trials. It's a simple, not painful, easy to understand method, used primarily to monitor the progression of disease, evaluate therapeutic responses, locks and evaluation of patients with neuropathy have loss or increased skin sensitivity.

 

Figure 1 - Test Sensitive Quantification. Termodo placed on the inner side of the forearm

Algometry pressure is a technique that aims to quantify the ability of perception and pain tolerance by physical stimuli (pressure on nociceptors). At the end of the device there is a round tip diameter of 1 cm is placed on the skin (Figure 2). Applies direct pressure to the pain start, measured in kilogram - force. The sites to perform the technique may vary according to the study protocol. Some of these locations may be: inside of the forearm and thigh and masseter muscle. According to the degree of myelination, neurotransmitters have different driving characteristics, thereby producing different clinical patterns. The perception threshold and pain tolerance of a certain neurotransmitter associated with the ability to capture nociceptive, upper and indirectly related to the excitatory controls superior inhibitory controls. When subliminal stimuli produce pain sensation (allodynia) or when the individual has reduced tolerance to painful stimuli ( hyperalgesia ) featuring break this harmony.

 

Figure 2 - pressure algometer

 

Conditional pain modulation test (CPM) is the brain's ability to regulate the experience of pain. It is a scientific test to investigate the endogenous analgesic way of this adjustment. A pain is produced by a stimulus (conditioning) into a body part. This pain is reduced by a concurrent other pain stimulus, that is, a second test in a distant part of the body. Is usually performed along with QST. One arm is held the QST and other CPM. CPM is accomplished by immersing the hand contralateral to the pain stimulus by QST in a bottle with cold water (Figure 3). The effect of reduced CPM is the evaluation of the first sensation of pain by the second stimulus of the test, also described as " pain inhibiting pain”. The Low CPM efficiency indicates a low capacity to inhibit endogenous pain through body systems. This fact is associated with various pain syndromes, including temporomandibular disorders, fibromyalgia and headache, chronic and neuropathic pain.

 

Figure 3 - Test conditioned pain modulation. QST and right arm with his left hand in cold water. Asks the individual to pay attention to the sensation of heat caused by QST while the left hand is in cold water. The purpose of the test is to make the brain divert attention from the painful sensation caused by heat and concentrate in cold water. But the individual must pay attention to the feeling of heat. CPM may also be carried out with cold water and algometry.

 

Projects & Pain Neuromodulation Group linked techniques:

A) Effect of stimulation and transcranial direct current eletrocacumpultura in pain, functional ability and cortical excitability in patients with osteoarthritis.

B) Study of the Brain by optical functional neuroimaging in patients with chronic pain by using psychotropic stimulation and transcranial

C) Studying the brain by optical functional neuroimaging in fibromyalgia patients using transcranial direct current stimulation.

D) Analysis of attentional capacity fribromialgia patients undergoing intervention with tDCS: randomized, blind, crossover, controlled-Sham tDCS.

E) Effect of transcranial magnetic stimulation on cortical, subcortical neuromodulation and pain thresholds in patients with chronic myofascial pain

 


 Validated scales by Pain&Neuromodulation Group

 

A - Validation of the Pain Catastrophizing Scale

B - Validation of Brazilian quantitative sensory testing (QST) Device

C - Validation of the Functional Pain Scale

D - Validation of the State-Trait Anxiety STAI Scale.

 

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