Transcranial Direct Stimulation in Chronic Pelvic Pain

Phase 2

Completed

Conditions: Healthy
Pelvic Pain

Interventions: Device: Transcranial Direct Current Stimulation

Registration Number: NCT01143636

Lead Sponsor: Spaulding Rehabilitation Hospital

Brief Summary: The purpose of this study is to determine whether transcranial direct current stimulation (tDCS) is effective in reducing pain in subjects with chronic pelvic pain. Our hypothesis is that tDCS will decrease pain significantly when compared to sham stimulation.

Detailed Description: The study encompasses two experiments: The first one involves patients with chronic pain, receiving 10 sessions of stimulation, active or sham (parallel design).

The second experiment involves involves healthy subjects, receiving active or sham tDCS over the primary motor cortex (crossover design).

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 35

Inclusion Criteria

Providing informed consent to participate in the study
18 to 64 years old
Having symptoms of pelvic pain for more than 6 months with an average of 3 on a 0-10 VAS scale (for pelvic pain subjects only)
No history of or current genitourinary tuberculosis as self reported
No history of urethral cancer as self reported
No history or current bladder malignancy, high grade dysplasia or carcinoma in situ as self reported
No occurrence of ovarian, vaginal or cervical cancer in the previous 3 years as self reported
No current vaginal infection as self reported
No active herpes in previous 3 months as self reported
No antimicrobials for urinary tract infections in previous 3 months as self reported
Never treated with cyclophosphamide as self reported
No radiation cystitis as self reported
No neurogenic bladder dysfunction (due to a spinal cord injury, stroke, Parkinson's disease, multiple sclerosis, spina bifida or diabetic cystopathy) as self reported
Absence of bladder, ureteral or urethral calculi for previous 3 months as self reported
No urethritis for previous 3 months as self reported
No urethral dilatation, cystometrogram, bladder cystoscopy with full anesthesia or bladder biopsy in previous 3 months as self reported
Must not be pregnant
Eligible to MRI according to MRI screening checklist
No contraindications to tDCS:
No history of alcohol or drug abuse within the past 6 months as self reported
No use of carbamazepine as self reported
Does not have severe depression (with a score of >30 in the Beck Depression Inventory)
No history of neurological disorders as self reported
No history of unexplained fainting spells as self reported,
No history of head injury resulting in more than a momentary loss of consciousness as self reported
Have had no neurosurgery as self reported
No history of psychological disorders as self reported
Must have the ability to feel pain as self reported

Exclusion Criteria

Not provided

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Active tDCS - pelvic pain patients	Transcranial Direct Current Stimulation	ACTIVE tDCS: Subjects will receive a total of 10 consecutive sessions of active tDCS over a two-week period (administered Monday - Friday). During each session, the anode electrode will be placed over the primary motor cortex of the predominantly painful side.
Active tDCS - healthy	Transcranial Direct Current Stimulation	The healthy controls will undergo one day of treatment with active tDCS. All participants will receive both active and sham stimulation in a randomized order.
Sham tDCS - healthy	Transcranial Direct Current Stimulation	The healthy controls will undergo one day of treatment with sham tDCS. All participants will receive both active and sham stimulation in a randomized order.
Sham tDCS - pelvic pain patients	Transcranial Direct Current Stimulation	SHAM tDCS: Subjects will receive a total of 10 consecutive sessions of sham tDCS over a two-week period (administered Mon-Fri). During each session, the anode will be placed over the primary motor cortex of the predominantly painful side.

Primary Outcome Measures

Name	Time	Method
Pain Assessment	baseline and at 2 weeks	We use the Visual analogue scale (VAS) to measure pain. The VAS is ranged from 0 to 10, with 0 reffering to no pain and 10 reffering the the worst possible pain. We used the difference between post treatment minus baseline to compare the two treatments (active versus sham tDCS).
Pressure Pain Threshold	baseline and at 2 weeks	Pressure pain threshold (PPT) is defined as the minimum force applied which induces pain. The change in pressure pain threshold (post minus pre intervention) is use for the analysis.

Secondary Outcome Measures

Name	Time	Method
Quality of Life Scale (QOLS)	2 weeks	The questionnaire on quality of life was performed at the end of the treatment session and compared between the two groups (active and sham) in patients with pelvic pain (Exp. 1). The QOLS has 16 items (total scores ranging from 16 to 112) the highest scores corresponding the best QOL.
Clinical Global Impression - CGI	2 weeks	This scale measures illness severity and was performed on patients with pelvic pain (Exp. 1). The scale was performed at end of the treatment and compared between the two groups (real and sham). The scale is divided in 3 sub-scales: Severity of illness (0-7), global improvement (0-7) and efficacy index (0-16), total scores ranging from 0 to 30. The highest scores corresponding to lowest clinical improvement.
Mini Mental Scale - MMS	2 weeks	This scale measures patients cognitive impairment. It was performed at the end of the treatment and compared between the 2 groups (real and sham) in patients with pelvic pain (Exp. 1). It is a 30 points scale (total scores ranging from 0 to 30), the highest score corresponds to the highest cognitive status.
Diffuse Noxious Inhibitory Controls - DNIC.	baseline and at 2 weeks	DNIC occurs when response from a painful stimulus (pain pressure threshold - PPT) is inhibited by another noxious stimulus (cold water). The difference between baseline and post treatment was compared between the 2 groups (real and sham) in patients with pelvic pain (Exp. 1).
Beck Depression Inventory - BDI.	2 weeks	BDI is a questionnaire used for detecting depression. It was performed at the end of the treatment and compared between the 2 groups (real and sham) in patients with pelvic pain (Exp. 1). It is a 21-question multiple-choice self-report inventory (scores ranging from 0 to 63 - 0 corresponds to no symptom of depression).
Pain Pressure Threshold Test - PPT	baseline and at 2 weeks	Pressure pain threshold (PPT) is defined as the minimum force applied which induces pain.This test was applied before and after the treatment and the difference (post minus pre) was compared between the 2 groups (real and sham) in patients with pelvic pain (Exp 1).
Visual Analogue Scale - Anxiety.This Scale Measures Patients' Level of Anxiety on a Scale (0-no Anxiety to 10-worst Anxiety Ever). It Was Performed at the End of the Treatment and Compared Between the 2 Groups (Real and Sham) in Patients With Pelvic Pain	2 weeks	The scale was performed at the end of the treatment and compared between the 2 groups (real and sham) in patients with pelvic pain (Exp. 1).
Patient Global Assessment - PGA	2 weeks	This scale measures patient's assessment of general health. It was performed at the end of the treatment and compared between the 2 groups (real and sham) in patients with pelvic pain (Exp 1). The patient has to answer the question "how is your health overall" on a scale going from 0 to 10 (0 being the worst, 10 being the best).
Von Frey	baseline and at 2 weeks	This test is used to test subjects' sensitivity to a mechanical stimulus. It was performed before and and after the treatment and the difference (post minus pre) was compared between the 2 groups (real and sham) in patients with pelvic pain (Exp. 1). A set of filaments, typically from 0.008 grams force up to 300 grams force, is applied on the patients' skin. The mechanical threshold is defined as the moment when the patient detects the stimulus.