Changes in Cerebral Blood Flow With Spinal Manipulative Therapy vs. Voluntary Motion

Study Overview
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Brief Summary
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The investigators are performing a study to determine whether changes in blood flow occur in the neck and back of the brain following a series of head positions and a manipulation of the upper neck. Each participant will be asked to undergo a series of MRI's to evaluate whether there are any changes in blood flow resulting from any of the head positions or manipulation. The study will be conducted over a period of 1 day and each participant can anticipate the testing to take approximately 120 minutes.

Detailed Description
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The goal is to further investigate the cerebrovascular hemodynamic consequences of cervical spine positions, including rotation and manipulation in-vivo under clinically relevant circumstances using two advanced forms of MRI technology on the VA and posterior cerebral vessels. According to the knowledge of the investigators, a study utilizing MRI and functional blood oxygen level dependent (fBOLD) imaging to examine blood flow and perfusion, turbulence and evidence of micro-trauma within these vessels has yet to be conducted.

Official Title
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Changes in Cerebral Blood Flow With Spinal Manipulative Therapy vs. Voluntary Motion

Conditions
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Vertebral Artery Dissection, Cerebrovascular Accident, Cerebrovascular Stroke

Intervention / Treatment
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* Other: head positions and spinal manipulation


Participation Criteria
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Eligibility Criteria
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Inclusion/Exclusion Criteria Enrolled and matriculated as a student in the Canadian Memorial Chiropractic College. Healthy asymptomatic male patients who would otherwise receive cervical manipulation on a regular basis as a part of their normal learning experience and will have had a cervical manipulation in the last 3 months. Sufficient English language ability to complete study questionnaires (see appendix). No history of disabling neck, arm or headache pain within the last 6 months. No current or prior history of neurological symptoms including, facial or extremity weakness, abnormal sensation to the face, body or extremities, uncontrolled movements, abnormal gait, dizziness, unexplained nausea/vomiting, difficulty with speaking or swallowing. Subjects will have had no prior history of head trauma or prior history of surgery to the neck region. No history of claustrophobia, metallic implants or tattoos to ensure compatibility with MRI requirements.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Masking: Single


Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: head positions and spinal manipulation|Each subject will then undergo a baseline MRI in a head neutral position (0 degrees rotation). They will then be placed in head rotation (45 degrees) to the non-dominant and undergo a MRI. Maximum rotation to the side with MRI will follow. Finally, each subject will receive an upper cervical rotary manipulation to the non-dominant side with MRI immediately after. A total of 4 test conditions will be evaluated (rest, 45 degree, maximal, post-manipulation). The manipulation will be performed by an experience practitioner on a bed just outside the MRI room in supine position. A controlled impulse load will be applied and the head/neck returned to neutral position. Prior to each maneuver, the subject will be queried on their comfort, condition and willingness to continue|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in advanced magnetic resonance imaging | A change in vertebral, posterior cerebellar and collateral arterial blood flow associated with various head positions and an upper cervical manipulation will be measured using blood oxygen level dependent (BOLD). A BOLD MRI generates a signal by tracking changes in the local oxyhemoglobin to deoxyhemoglobin ratio. Signal changes are due to a combination of altered microvascular perfusion, blood volume, and fluctuations in cellular metabolism. It will also provide more sensitivity in determining the impact of changes in blood flow during the various head positions. | immediately after head positions. |