DISEASES OF THE MIDDDLE EAR (AB) Flashcards
(106 cards)
What is the air-filled space in the temporal bone medial to the tympanic membrane?
Middle ear cavity
What are the three divisions of the middle ear relative to the tympanic membrane?
Epitympanum, Mesotympanum, Hypotympanum
What structure forms the medial wall of the middle ear cavity?
Cochlear promontory
What structure marks the medial wall of the middle ear posteriorly?
Oval window superiorly occupied by the stapes and round window inferiorly
What structure extends posterior to the oval and round windows and medial to the vertical facial nerve?
Sinus tympani
What structure transmits the stapedial tendon to the stapes superstructure?
Pyramidal eminence
What structure is marked by the inferior rim of the tympanic annulus and limited inferiorly by the jugular bulb posteriorly?
Hypotympanum
What is almost completely partitioned from the mesotympanum by the ossicular chain and mucosal folds?
Epitympanum
What bones articulate in the epitympanum to form an ossicular mass?
Body of the incus and head of the malleus
What is the most common infection of the middle ear?
Acute otitis media
What is the duration of acute otitis media?
3 weeks
What seasonal variation increases the incidence of acute otitis media?
Colder months due to upper respiratory tract infections
Why does upper respiratory tract infection predispose to acute otitis media?
Due to Eustachian tube dysfunction
What two muscles open the Eustachian tube?
Tensor veli palatini and levator veli palatini
Why does cleft palate predispose an individual to acute otitis media?
Lack of midline muscle union prevents Eustachian tube opening
What age group has the highest incidence of acute otitis media?
6 to 24 months
What factor has been shown to reduce the risk of acute otitis media in children?
Extended breastfeeding
What is the most common tympanic membrane finding in acute otitis media?
Opaque, bulging, erythematous or congested TM
What test assesses TM mobility in acute otitis media?
Pneumatic otoscopy
What is a common symptom in infants with acute otitis media?
Irritability, vomiting, diarrhea
What bacterial pathogens are commonly associated with acute otitis media?
Streptococcus pneumoniae, Haemophilus influenzae, Branhamella catarrhalis
What is the most common type of otitis media?
Bacterial otitis media
What type of otitis media occurs in severely ill children with systemic disease?
Necrotic otitis media
What are the five stages of otitis media?
Hyperemia, Exudative, Suppurative, Coalescence, Complications and resolution