Schwartz operation is done in -: (A) CSOM, (B) Serous otitis media, (C) Otosclerosis, (D) Acute mastoiditis
Answer is D. Indications of simple / cortical mastoidectomy (Schwartz operation)

Acute coalescent mastoiditis.
Incompletely resolved acute otitis media with reservoir sign.
Masked mastoiditis.
As a initial step to perform:


Endolymphatic sac surgery
Decompression of facial nerve
Translabyrinthine or retrolabyrinthine procedures for acoustic neuroma.