Hi, thanks for using healthcare magic
Granulation tissue is essentially scar tissue and the report states that the opacity (dark area) seen in the left middle ear may be due to fluids/mucus or granulation (scar tissue from a previous infection or trauma).
The overall findings state the the signs may be due to bilateral (on both sides) mastoiditis
. Mastoiditis is an infection that extends to the air cells of the skull behind the ear.
Your doctor will likely prescribe antibiotics to treat the infection
I hope this helps