Prussak’s space is the small middle ear recess. It lies medial to pars faccida, lateral to the neck of malleus, above the lateral process of malleus and inferior to the lateral malleal ligament. The lateral malleal ligament also bounds it anteriorly and posteriorly. Posteriorly, it also has a gap through which the space communicates with epitympanum.
Boundaries
- Laterally : Flaccida part of Sharpnell’s membrane
- Superiorly : Scutum and lateral malleal ligament
- Inferiorly : Short process of malleus
- Medially : neck of malleus
- From the neck of malleus the anterior malleolar fold and anterior ligament are demarcating Prussak’s space anteriorly. Ventilation of Prussak’s space is only possible posteriorly above the posterior malleolat fold.
- It communicates with the posterior pouch of the von Trollsh.
- It is named after the Russian otologist Alexander Prussak.
Prussak’s space is the sub component of the lateral epitympanic space and extends from the level of scutum to the umbo. This space is bent demonstrated radiologically on the oblique coronal image.
This space can play an important role in the retention of keratin and subsequent development of cholesteatoma. A cholesteatoma form when there is a deep retraction pocket in IM. The lining of the tympanic membrane which is skin(epithelium )is shed but if the membrane is retracted it gets trapped. The debris collects and enlarges and ultimately forms a cholesteatoma. This cholesteatoma in turn can erode the middle ear ossides, facial nerve, inner ear and even involve the brain.
From Prussak’s space located in epiyympanum cholesteatoma patterns of spread are:
- Posterior epitympanum : through superior includal space to mastoid antrium
- Posterior mesotympanum : inferiorly through the posterior pouch of von Troeltsch to staples, round window, sinus tympani and facial recess.
- Anterior epitympanum: Anterior to head of malleus, may gain access to supratubal recess via anterior pouch of von troeltsch.
