MCQ – 43659

Correct Answer » D Explanation

The middle ear (tympanic cavity) is divided into three parts based on its relation to the tympanic membrane:

1. Epitympanum (Attic) – part above the tympanic membrane

2. Mesotympanum – part opposite the tympanic membrane

3. Hypotympanum – part below the tympanic membrane

Narrowest Part of the Middle Ear

The mesotympanum is considered the narrowest portion of the middle ear cavity.

The narrowest point specifically lies:

• Between the umbo of the tympanic membrane

• And the promontory on the medial wall

The distance between these structures is about 2 mm, making this the most constricted region of the middle ear.

This narrow space is clinically important because:

• It contains parts of the ossicular chain (malleus and incus)

• It is a key area involved in middle ear infections and surgeries.