Prussak's space is the most common origin of acquired (primary) attic cholesteatoma. Which boundaries define Prussak's space?

• A Lateral wall: pars flaccida; medial wall: neck of malleus; superior: lateral malleolar fold; inferior: lateral malleolar fold ✓
• B Lateral wall: pars tensa; medial wall: incus; superior: tegmen tympani
• C Lateral wall: bony annulus; medial wall: stapedial tendon; superior: incus long process
• D Lateral wall: posterior canal wall; medial wall: oval window; inferior: round window niche

Explanation

Prussak's space (the lateral epitympanic space) is a small recess bounded: laterally by the pars flaccida (Shrapnell's membrane) and squama, medially by the neck of the malleus and the lateral malleolar fold, superiorly by the lateral malleolar fold, and inferiorly by the lateral malleolar fold. It is the site where pars flaccida retraction begins, forming a retraction pocket that accumulates squamous epithelium, initiating primary acquired cholesteatoma. Understanding these boundaries explains why attic perforations (in pars flaccida) are the hallmark of unsafe CSOM.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.