Notice the bulgin portion of the ear drum: cholesteatoma grows from tissue of ear drum
squamous cell carcinoma is on skin cells, usually found on pinna or concha in addition to face, arms, legs, etc.
otosclerosis occurs in the middle ear space so otoscopy wont reveal it
post myringotomy scarring refers to scar tissue from the placement of tubes through the eardrum. no bulge would show.