Overview-rhinology, allergy, immunology Flashcards
What cells contribute to the formation of the nose
during the 4th week of embryogenesis?
Neural crest cells
Before closure during embryogenesis, what are the
following spaces called?
● Between the frontal and nasal bones
● Between the frontal and ethmoid bones
● Between the nasal bones and nasal capsule
Fronticulus nasofrontalis
Foramen cecum
Prenasal space
What embryologic structures form within the thickened ectoderm of the nasal placodes of the frontonasal process and after dividing each placode into medial and lateral nasal processes become the early nasal cavities?
Nasal pits
Into what structures do the (1) medial and (2)
lateral processes of the nasal pits and the (3)
maxillary process of the maxilla develop?
● Medial: Nasal septum (from the globular processes of
His), philtrum, premaxilla
● Lateral: Nasal alae
● Maxillary process: Lateral nasal wall
What embryologic membrane separates the nasal and oral cavities, and normally degenerates to allow open passages as the choanae are formed by the deepening olfactory pits during development?
Nasobuccal membrane
The nasal bones attach to what structures within
the facial skeleton?
Frontal bone, nasal process of the maxilla, upper lateral
cartilages, contralateral nasal bone, perpendicular plate of
the ethmoid, and cartilaginous septum
What are the three different regions of the paired lower lateral cartilages of the nose?
● Medial crus
● Intermediate crus
● Lateral crus
What is the name of the area that connects the
lower lateral cartilages with the upper lateral
cartilages?
Scroll region
What are the boundaries of the internal nasal
valve?
● Caudal septum
● Head of the inferior turbinate
● Remainder of tissues around the piriform aperture
● Upper lateral cartilage, distal end
What structure does the frontal process of the
maxilla, nasal floor, and lateral fibrofatty tissue
form?
Piriform aperture
What are the boundaries of the external nasal
valve?
● Caudal septum
● Lower lateral cartilage (caudal edge of the lateral crus,
junction with the upper lateral cartilage)
● Piriform aperture
Name the components of the nasal septum.
● Perpendicular plate of the ethmoid bone ● Quadrangular cartilage ● Vomer ● Maxillary crest ● Palatine bone
What is the blood supply of the nasal septum?
● Anterior and posterior ethmoid arteries (superior sep-
tum)
● Sphenopalatine artery branches/posterior septal branch
(posterior/inferior septum)
Most cases of epistaxis arise in what area?
Kiesselbach plexus (Little area), anterior septum
The uncinate process is an extension of
what bone?
Ethmoid bone
What are the three most common superior attach-
ment points for the uncinate?
● Lamina papyracea
● Skull base
● Middle turbinate
How does the superior attachment of the uncinate process relate to the drainage of the frontal sinus outflow tract?
When attached to the lamina papyracea, the frontal sinus usually drains medial to the uncinate, and when it is attached to the skull base or middle turbinate, it often drains lateral to the uncinate.
What is the opening to the space between the
uncinate process and the ethmoid bulla called?
Semilunar hiatus
The uncinate process covers the medial aspect of which space that provides a common drainage pathway for some of the anterior sinuses?
(Ethmoidal) Infundibulum
True or False. The uncinate attaches to the ethmoid
crest of the maxilla, the lacrimal bone, the
ethmoidal process of the inferior turbinate bone,
and the palatine bone via the lamina perpendicularis.
True
The lamina papyracea is formed by which bone?
Ethmoid bone
The nasolacrimal duct empties under
what structure in the nose?
Inferior turbinate (via the Hasner valve)
What is the name for a pneumatized middle turbinate, which is an extension of the ethmoid bone?
Concha bullosa
The middle turbinate attaches superiorly to the lateral aspect of the cribriform plate, laterally to the lamina papyracea/maxillary sinus, posteriorly to the lateral wall just anterior to the crista ethmoidalis of the palatine bone, and anteriorly near the agger nasi to what structure, which is a
part of the frontal process of the maxilla?
Cristal ethmoidalis of the maxilla
What structure separates the anterior and
posterior ethmoid sinuses?
Ground or basal lamella
What are the five ethmoturbinals, and
what do they become?
First → Agger nasi (ascending portion) and uncinate process
(descending portion)
Second → Middle turbinate
Third → Superior turbinate
Fourth and fifth fuse → supreme turbinate
List the first four ethmoid lamellae.
● Uncinate process
● Ethmoid bulla
● Basal lamella of the middle turbinate
● Lamella of the superior turbinate
What is the horizontal plate of the ethmoid bone
that forms the roof of the ethmoid sinus and
separates the ethmoid air cells from the anterior
cranial fossa called?
Fovea ethmoidalis
What are the three infundibular cells that are
anterior ethmoid air cells?
● Agger nasi cells
● Terminal cell (recessus terminalis)
● Suprainfundibular cell
Which cell type is the most anterior of the
ethmoid cells and forms near the attachment of
the middle turbinate to the lateral nasal wall?
Agger nasi cell(s)
After removing the uncinate process, the ethmoid
bulla typically sets just anterior to the basal
lamella. Where does this sinus drain?
Suprabullar or retrobullar recess (sinus lateralis)
What arterial structure typically runs
through the roof of the ethmoid bulla?
Anterior ethmoid artery
The middle meatus, uncinate, infundibulum,
anterior ethmoid cells, and ostia (frontal, ethmoid,
maxillary) collectively are referred to as what?
Ostiomeatal complex
What is the name of the infraorbital ethmoid air
cells that pneumatize into the maxillary sinus and
can narrow the maxillary sinus ostium?
Haller cells
In the adult, the posterior ethmoidal complex
consists of one to five cells, which typically drain
into which space?
Superior or supreme meatus
Air cells that pneumatize lateral or posterior to
the anterior wall of the sphenoid sinus are called
what?
Onodi cells (sphenoethmoidal cell)
What is the first sinus to develop embryologically?
Maxillary sinus
What structure must be removed to visualize the
natural ostium of the maxillary sinus?
Uncinate process
Where is the most common location for the
maxillary ostium within the infundibulum?
Inferior third (65%)
Where are the anterior and posterior nasal
fontanelles located?
Located anterior and posterior to the inferior aspect of the
uncinate process
What structure runs through the roof of the
maxillary sinus?
Infraorbital nerve
A series of three or four frontal furrows arise out
of the ventral middle meatus and give rise to
what?
● First frontal furrow = agger nasi cell
● Second frontal furrow = frontal sinus
● Third and fourth furrow = anterior ethmoid cells
What is the last sinus to fully develop, and at
what age has it typically reached full size?
Frontal sinus. Late teens
The frontal sinus drains via the frontal sinus
outflow tract or frontal recess into which space?
Ethmoid infundibulum (most common)
The frontal or frontoethmoidal cells are located superior to the agger nasi cell and can have quite variable pneumatization. Describe the four Kuhn types of pneumatization.
● Type I: Single cell superior to the agger nasi but not
extending into the frontal sinus
● Type II: Tier of two or more cells above the agger nasi but
below the orbital roof
● Type III: Single cell extending from the agger nasi into the
frontal sinus
● Type IV: Isolated cell within the frontal sinus
What type of cell can be found posterior to the
frontal sinus and superior to the orbit?
Supraorbital ethmoid cells
The spread of frontal sinus infections intracranially
is commonly thought to pass through what
structures?
Foramina of Breschet (small venules that drain the frontal sinus mucosa to the dural veins)
How is the sphenoid sinus formed during
development?
Nasal mucosa invaginates into the cartilaginous nasal
capsule, which forms the cupolar recess. The wall of this
recess becomes ossified later in development into the
ossiculum Bertini. The cartilage is resorbed in the 2nd and
3rd years of life, and the ossiculum attaches to the
sphenoid bone. Pneumatization then progresses and is
complete in the 9th to the 12th years.
What is the most posterior paranasal
sinus, and where does its natural ostium drain?
Sphenoid sinus; sphenoethmoidal recess (between the superior turbinate and the anterior wall of the sphenoid sinus)
Describe four surgical landmarks to help safely
identify the natural ostium of the sphenoid sinus.
● 6.2 to 8.0 cm from the anterior nasal spine
● 30 to 40 degrees from the nasal floor
● Medial to the posterior end of the superior turbinate
(85%)
● ~ Halfway up the anterior sphenoid wall
The carotid artery is reported to be dehiscent in the sphenoid sinus in what percent of patients?
~ 15%
What are the main types of sphenoid pneumatization in the Hamberger classification?
● Conchal type: No pneumatization
● Presellar type: Pneumatization restricted anterior to a
vertical plane passing through the anterior clinoid
process
● Sellar type: Well-pneumatized, most common (90%); can
be complete or incomplete depending on whether the
pneumatization extends to the clivus
When removing the intersinus septum within a
sphenoid sinus, attachment of this septation to
what critical structure must be considered?
Internal carotid artery
What is the space between the internal carotid
artery and the optic nerve within the sphenoid
sinus called?
Opticocarotid recess