How long for a decision on Medical after interview?

[FinallyHouston]

Dear all,
Does anyone know how long it takes a USCIS officer to make a decision on a medical exam submitted after the interview.
My interview was held in the Houston office on December 8. The officer explained my medical had expired and that I would need an updated one. I submitted my updated exam on December 14th. My case status online reads "Correspondence was received and it is being reviewed".

Any help is appreciated!