Yes, you can use the base for quality checking and editing. In some cases you may need to check the cross-sectional runs for a subject --but it is especially important that the base is accurate for the longitudinal runs to be accurate as well. After editing the base, you shouldn't need to make edits to the long runs (or at least very minimal edits should be needed).

From: freesurfer-bounces@nmr.mgh.harvard.edu <freesurfer-bounces@nmr.mgh.harvard.edu> on behalf of Eszter Boros <boros.eszter0226@gmail.com>
Sent: Thursday, November 18, 2021 12:13 PM
To: Freesurfer support list <freesurfer@nmr.mgh.harvard.edu>
Subject: [Freesurfer] longitudinal analysis – Is correcting the Base enough?

External Email - Use Caution

Dear FreeSurfer Team,

I am working with a longitudinal design (before and after treatment), and based on the website's recommendation (MailScanner has detected a possible fraud attempt from "secure-web.cisco.com" claiming to be https://surfer.nmr.mgh.harvard.edu/fswiki/LongitudinalEdits)

editing the Base could be enough for this.

If I understand this right, I should generate the Base image (without editing the two Cross images) and then edit the Base only.

After that, I could create the two longitudinal runs (Long) without editing them as well.

Did I get this right?

This could save a huge amount of time since I should edit one image (Base) instead of two (Cross images).

I am using Freesurefer 7.1.1.

Thank you for your answer! I greatly appreciate it.

All the best,

Eszter Boros