Yes - It is possible to either manually or automatically rescan individual creatives or entire campaigns.
To manually rescan simply select the creative within the campaign.
Multiple creatives can be selected at once if required.
Click Perform actions
Advalidation will then perform a full QA and return the new results.
This can be useful if you want to validate that a specific result is correct but may have been different from what you were expecting.
It is also possible to automatically rescan creatives and campaigns by using Campaign Monitoring.