Estimating Brain Biomechanics Using MRI

Sponsor

National Institutes of Health Clinical Center (CC) (NIH)

Overall Status

Recruiting

CT.gov ID

NCT01633268

Collaborator

(none)

194

Enrollment

Location

Study Details

Study Description

Brief Summary

Objective: In this study we will develop and apply imaging techniques to perform the first three-dimensional (3-D) measurements of brain biomechanics during mild head movement in healthy human subjects. Biomechanics is the application of mechanics, or the physical principles in action when force is applied to an object, to the anatomical structure and/or function of organisms. Such techniques will be invaluable for building computational models of brain biomechanics, understanding variability of brain biomechanics across individual characteristics, such as age and sex, and determining brain sub-structures at risk for damage when movement of the head is accelerated, such as during a traumatic event.

Study Population: Measurements will be performed on 90 healthy men and women aged 18-65.

Design: We will build upon the model pioneered by our collaborator, Dr. Philip Bayly. The model places a human subject in a magnetic resonance (MR) scanner with one of two head support units that allows a specific range of motion. Each head support is latched such that it can be released by the subject, and results in either a rotation of the head of approximately 30 degrees or a flexion-extension of the head of approximately 4 degrees. Although both supports are weighted so that the motion is repeatable if the subject is relaxed, the subject can easily counteract the weight. The resulting acceleration/deceleration is small (in the range of normal activities, such as turning one's head during swimming) and has been validated and used in other human investigations of brain biomechanics. The subject repeats the motion multiple times during the MR scan under their own volition and desired pace to measure motion of the head and brain.

Outcome measures: This project is a pilot study evaluating the potential of extracting three-dimensional estimates of brain deformation, such as strain measurements, using MR imaging. A primary outcome of this project will be a fast MR acquisition sequence for measuring 3-D brain deformation. The sequence will be evaluated by applying the protocol to human subjects, followed by preliminary quantification of the reproducibility and stability of deformation measurements.

Condition or Disease	Intervention/Treatment	Phase
Healthy Volunteer Traumatic Brain Injury Brain Mapping Craniocerebral Trauma Magnetic Resonance Imaging

Detailed Description

Objective

In this study we will develop and apply imaging techniques to perform the first three-dimensional (3-D) measurements of brain biomechanics during mild head movement in healthy human subjects. Biomechanics is the application of mechanics, or the physical principles in action when force is applied to an object, to the anatomical structure and/or function of organisms. Such techniques will be invaluable for building computational models of brain biomechanics, understanding variability of brain biomechanics across individual characteristics, such as age and sex, and determining brain sub-structures at risk for damage when movement of the head is accelerated, such as during a traumatic event. Using the developed imaging techniques above, we will acquire a sufficient number of data sets to create templates of the average brain response and stiffness based on age and sex. Anonymized raw and processed data will be made publicly available to improve computational models of brain biomechanics.

Study Population

Measurements will be performed on 194 healthy men and women aged 18-65.

Design

We will build upon the model pioneered by our collaborator, Dr. Philip Bayly. The model places a human subject in a magnetic resonance (MR) scanner with one of two head support units that allows a specific range of motion. Each head support is latched such that it can be released by the subject, and results in either a rotation of the head of approximately 30 degrees or a flexion-extension of the head of approximately 4 degrees. Although both supports are weighted so that the motion is repeatable if the subject is relaxed, the subject can easily counteract the weight. The resulting acceleration/deceleration is small (in the range of normal activities, such as turning one's head during swimming) and has been validated and used in other human investigations of brain biomechanics. The subject repeats the motion multiple times during the MR scan under their own volition and desired pace to measure motion of the head and brain. Additionally, we will use a type of MRI called magnetic resonance elastography (MRE), which measures brain motion in response to mild head vibration, to investigate brain stiffness.

Outcome measures

This project is a study evaluating the potential of extracting three-dimensional estimates of brain deformation, such as strain measurements and stiffness, using MR imaging. A primary outcome of this project will be MRI techniques for characterizing 3-D brain biomechanics. The techniques will be evaluated by applying the protocol to human subjects, followed by preliminary quantification of the reproducibility and stability of deformation and stiffness measurements. Acquired data will be made publicly available for use by the research community.

Study Design

Study Type:

Observational

Anticipated Enrollment :

194 participants

Observational Model:

Cohort

Time Perspective:

Prospective

Official Title:

Estimation of Brain Biomechanics Using MRI

Actual Study Start Date :

Jul 4, 2012

Arms and Interventions

Arm	Intervention/Treatment
Healthy Volunteers Healthy men and women aged 18-65

Outcome Measures

Primary Outcome Measures

technical development of a method for providing three-dimensional measurements of brain biomechanics in vivo using MR imaging. [Day 1 of study]
Primary outcome of this project will be a fast MR acquisition sequence for measuring 3-D brain deformation. The sequence will be evaluated by applying the protocol to human subjects, followed by preliminary quantification of the reproducibility and stability of deformation measurements

Secondary Outcome Measures

Measure of preliminary database of brain deformation [End of study]
A preliminary database of brain deformation measurements from a healthy cohort will allow initial characterization of the variability of brain response across sex and age.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 65 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

INCLUSION CRITERIA:
Between 18 and 65 years of age
Able to provide written informed consent
Able to lie flat for up to 2 hours
Able to move head up to 220 times within 45 minutes without discomfort
Good general health based on History and Physical (H&P) or History and Assessment (H&A)

EXCLUSION CRITERIA:

Contra-indications to MRI scanning without contrast based on RADIS department MRI safety questionnaire
Pregnancy
Inner ear problems causing vertigo
History of spinal cord injury, head injury or other musculoskeletal condition that may result in an aversion to or difficulty with turning one s head multiple times in succession
Claustrophobia (no sedation is permitted under this protocol)
Weight more than 250 lbs
Height greater than 6'4"
All employees/staff supervised by the Principle Investigator or Lead Associate Investigator are excluded from participation.