The Juventus midfielder underwent surgery on a meniscus complaint in May, and made his return as a 77th-minute substitute in a friendly with Northern Ireland on Wednesday.
There had been concerns the player would not be fit for Chile's tournament curtain-raiser against Australia on Friday, but the Chilean Football Association revealed the scan had only indicated inflammation in line with Vidal's planned recovery.
"The procedure, overseen by the head doctor of the Chilean team, Dr Giovanni Carcuro, was aimed at assessing the recovery process that he is going through after surgery on the joint in May," read the statement.
"The examination showed an inflammatory process associated with surgery performed and which is within the parameters expected for this time of recovery."
As well as Australia, Chile will meet Spain and the Netherlands in Group B.
