Investigation of Cortico-Rectal Pathways in Healthy Subjects and Constipated Patients

NCT ID: NCT01300897

Last Updated: 2018-07-23

Basic Information

• Recruitment Status: UNKNOWN
• Total Enrollment: 150 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2005-08-31
• Study Completion Date: 2018-12-31

Brief Summary

Biofeedback therapy improves bowel symptoms and anorectal function in patients with dyssynergic defecation, however its mechanism of action is not known. The investigators hypothesize that biofeedback therapy enhances gut-brain-gut communication by altering cortical processing of information and improving cortically mediated neuromuscular function of the gut. However, in order to better understand these mechanisms in patients, the investigators need to examine and establish normative data and compare findings with healthy subjects. The investigators specific aims are to examine and evaluate the following 40 normal subjects; (1) To evaluate the afferent cortical evoked potentials in response to the electrical stimulation of the anorectum and (2) To evaluate the corticofugal tracts (efferent) by recording the anal and rectal electromyographic responses following noninvasive lumbosacral and transcranial magnetic stimulation.

Detailed Description

1. Cortical evoked potentials:A probe with 2 ring electrodes is placed in anus and rectum. A small amount of electrical current is passed. The cortical evoked responses to the anal and rectal electrical stimulation is measured from the scalp using a neurophysiology recorder.

2. Motor evoked potentials: A magnetic coil is placed on the scalp at the anorectal cortical site and discharged using magnetic energy. The anal and rectal motor evoked potentials are then measured using a probe with 2 ring electrodes.

Conditions

Healthy Volunteers; Constipation

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: PROSPECTIVE

Study Groups

Healthy Volunteer

healthy volunteers will serve as controls. In each subject the cortical evoked potentials, transcranial motor evoked potentials and translumbosacral motor evoked potentials will be measured.

Cortical Evoked Potentials

Intervention Type: PROCEDURE

A probe with 2 ring electrodes is placed in the anorectum. A small amount of electric current is passed separately through the anal and rectal electrodes.. The cortical evoked potentials from the anal and rectal sites are measured.

Transcranial motor evoked potentials

Intervention Type: PROCEDURE

A probe with 2 ring electrodes is placed in the anorectum. A magnetic coil is placed on the scalp at the anorectal site on each side, and discharged using magnetic energy. The motor evoked potentials at the anal and rectal sites are measured.

Translumbosacral motor evoked potentials

Intervention Type: PROCEDURE

A probe with 2 ring electrodes is placed in the anorectum. A magnetic coil is placed on the back at the lumbar plexus and sacral plexus levels and discharged using magnetic energy. The motor evoked potentials at the anal and rectal sites are measured.

Constipated patients

Patients with chronic constipation and rectal hypersensitivity or hyposensitivity and/or dyssynergic defecation.In each subject the cortical evoked potentials, transcranial motor evoked potentials and translumbosacral motor evoked potential will be measured

Cortical Evoked Potentials

Intervention Type: PROCEDURE

A probe with 2 ring electrodes is placed in the anorectum. A small amount of electric current is passed separately through the anal and rectal electrodes.. The cortical evoked potentials from the anal and rectal sites are measured.

Transcranial motor evoked potentials

Intervention Type: PROCEDURE

A probe with 2 ring electrodes is placed in the anorectum. A magnetic coil is placed on the scalp at the anorectal site on each side, and discharged using magnetic energy. The motor evoked potentials at the anal and rectal sites are measured.

Translumbosacral motor evoked potentials

Intervention Type: PROCEDURE

A probe with 2 ring electrodes is placed in the anorectum. A magnetic coil is placed on the back at the lumbar plexus and sacral plexus levels and discharged using magnetic energy. The motor evoked potentials at the anal and rectal sites are measured.

Interventions

Cortical Evoked Potentials

A probe with 2 ring electrodes is placed in the anorectum. A small amount of electric current is passed separately through the anal and rectal electrodes.. The cortical evoked potentials from the anal and rectal sites are measured.

Intervention Type: PROCEDURE

Transcranial motor evoked potentials

A probe with 2 ring electrodes is placed in the anorectum. A magnetic coil is placed on the scalp at the anorectal site on each side, and discharged using magnetic energy. The motor evoked potentials at the anal and rectal sites are measured.

Intervention Type: PROCEDURE

Translumbosacral motor evoked potentials

A probe with 2 ring electrodes is placed in the anorectum. A magnetic coil is placed on the back at the lumbar plexus and sacral plexus levels and discharged using magnetic energy. The motor evoked potentials at the anal and rectal sites are measured.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• Right-handed adults between ages 18 years and 99 years, who are free of bowel disorders or other medical illnesses.

Exclusion Criteria

• Potential subjects with comorbid illnesses; severe cardiac disease, chronic renal failure or previous gastrointestinal surgery except cholecystectomy and appendectomy.
• Neurologic diseases e.g.; head injury, epilepsy, multiple sclerosis, strokes, spinal cord injuries.
• People who have metal in their skull or under the skull, or have metal in the back or hips.
• People who have a cardiac pacemaker, implanted defibrillator or medication pump.
• Impaired cognizance (mini mental score of < 15) and/or legally blind.
• Pregnant or likely to conceive during the course of the study. Women with potential for pregnancy must be willing to use contraceptive measures during the study.
• Previous pelvic surgery, rectocele repair, bladder repair, radical hysterectomy.
• Rectal prolapse or anal fissure or anal surgery.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 85 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Augusta University

OTHER

Sponsor Role: lead

Responsible Party

Satish Rao

Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Satish SC Rao, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Augusta University

Locations

University of Iowa Hospitals and Clinics

Iowa City, Iowa, United States

Countries

United States

Other Identifiers

5R01DK057100

Identifier Type: NIH

Identifier Source: secondary_id

View Link

5R01DK057100-2

Identifier Type: -

Identifier Source: org_study_id