6. Clinical: Tympanic Memb. & Ossicles Flashcards
(12 cards)
What are the three layers of the tympanic membrane?
Outer ectoderm (skin), middle fibrous layer, and inner endoderm (mucosa).
What part of the tympanic membrane lacks the fibrous layer?
Pars flaccida.
What is the most mobile part of the tympanic membrane?
Umbo.
Which part of the tympanic membrane is used for incisions in myringotomy?
Pars tensa (anteroinferior quadrant).
What is the normal color of a healthy tympanic membrane?
Pearly gray and translucent.
Which ossicle is embedded in the tympanic membrane?
Handle of malleus.
What type of joint connects the incus and stapes?
Ball-and-socket synovial joint.
Which ossicle is most commonly necrosed in chronic otitis media?
Long process of incus.
What is the smallest bone in the human body?
Stapes.
What is the function of the ossicular chain?
Transmits sound from tympanic membrane to oval window.
What forms the “ice cream cone” appearance on otoscopy?
Head of malleus (ice cream) and body of incus (cone).
What is the anatomical orientation of malleus and incus?
Vertical; stapes lies horizontally.
