Results from two NeuroQuant Extended Analyses are used to perform a “Longitudinal Analysis.” Whereas the purpose of the Extended Analysis is to test for atrophy of brain parenchymal regions and enlargement of ventricular regions at one point in time, the purpose of the Longitudinal Analysis is to test for progressive atrophy of brain parenchymal regions and enlargement of ventricular regions by examining and comparing two points in time.
The Longitudinal Analysis used comparisons with the 20 normal control subjects described above. Each normal control had 2 MRI scans done.
The normal changes in brain volume for the 15 brain regions were calculated.
For the Longitudinal Analysis, the patient will have MRI scans done at two points in time and a NeuroQuant Standard Analysis will be done for each. The changes in brain volume for each of the 15 brain regions will be calculated using the same methods that were used for the normal controls. For each brain region, the patient’s annualized percentage change in brain volume will be compared to the normal mean and standard deviation and a Z score will be calculated. Finally, each Z score will be converted to a percentile rank.
Click here to see our published papers on longitudinal analysis.