Clinical Trial: Longitudinal Monitoring of Cerebral Connectivity 3T MRI in Patients With a Transcient Global Amnesia

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Interventional

Official Title: Longitudinal Monitoring of Cerebral Connectivity 3T MRI in Patients With a Transcient Global Amnesia

Brief Summary:

The transient global amnesia (IA) is defined clinically as a temporary suspension and isolated from the ante and retrograde memory, totally regressing within 24 hours. The causes of AI remain unknown. The diagnosis of IA is based on consensus clinical criteria including the absence of associated location marks. In clinical practice, the MRI is often performed in conjunction with clinical examination because it ensures the absence of differential diagnoses, including stroke.

The visualization of MRI signal abnormalities related to AI directly dependent on the completion time of the review in relation to the onset of symptoms. Typically, no signal abnormality is visible in the hyperacute phase (ie D0-D1) while punctate appear hyperintense on diffusion sequences in hippocampal structures from J2 to J7 to disappear completely. It has been previously demonstrated that the use of higher values of b and / or a better spatial resolution significantly increases the sensitivity of the broadcasting sequence for the detection of these abnormalities hippocampal signal. At St. Joseph Hospital, Investigators explore the AI suspected patients with diffusion tensor sequence (DTI) on our high resolution 3T MRI.

Compared to the classical diffusion sequence, DTI is characterized by the use of a greater number of directions in which the diffusion gradients are applied. One advantage of this technique is to be able to perform tractography of white matter fibers. Thus the "connectome" is a new technique for post-processing of DTI images based tractography and to assess all the networks of nerve fibers in the brain. By this technique, the values of average diffusivity (MD) and fractional anisotropy (FA) can be measured along each of the studied nerve fibers. Group studies thus become feasible to compare quantitatively healthy subjects a

Detailed Summary:

  1. / OBJECTIVES

    The main objective of our study is, using the DTI realized 3T to:

    1.1 Main Objective

    - Highlight changes in brain connectivity induced by the occurrence of transient global amnesia in acute and monitor these remote anomalies (up to 1 year after the initial episode IA).

    1.2 Secondary Objectives

    • Correlate brain connectivity abnormalities identified data of neuropsychological examination
    • Correlate brain connectivity abnormalities identified o Brain morphological data (volumes of gray matter, white matter, hippocampal structures and LCS) o potential hippocampal hyperintensities visible in the acute phase of the diffusion images (number and laterality)

    1.3 Methodology

    DESIGN: biomedical, prospective single-center on topics of AI episode as part of their medical care within the hospital group Paris Saint-Joseph, 185 Rue Raymond Losserand 75014 Paris.

    Study duration: 2 years from May 2015 in the rate of inclusion estimated to average 2-3 patients per month (ie inclusion period of one year: from May 2015 to May 2016 and last follow-up in May 2017 ).

    start and end dates: May 2015 to May 2017 Number of topics to include: This is an exploratory study, single center, on a rare disease, the incidence of stroke is estimated amnesia of 3 to 8 patients per 100 000 per year according to recent studies.

    • Assessment of change of connectivity graphs representative of the FA (fraction anisotropy) facts [ Time Frame: Day 2, 1 year ]
      Comparison of connectivity graphs representing the FA values between the three groups of subjects : normal subjects , patients explored J2, explored patients at 1 year
    • Assessment of change of connectivity graphs representative of the MD (mean diffusivity) facts [ Time Frame: Day 2, 1 year ]
      Comparison of connectivity graphs representing the MD values between the three groups of subjects : normal subjects , patients explored J2, explored patients at 1 year


    Original Primary Outcome: Same as current

    Current Secondary Outcome:

    Original Secondary Outcome:

    Information By: Groupe Hospitalier Paris Saint Joseph

    Dates:
    Date Received: June 2, 2016
    Date Started: July 6, 2015
    Date Completion: September 1, 2017
    Last Updated: February 19, 2017
    Last Verified: June 2016