Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.
-
Upload
irea-purcell -
Category
Documents
-
view
221 -
download
0
Transcript of Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.
![Page 1: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/1.jpg)
drtbalu's otolaryngology online 1
Radiological anatomy of Frontal sinus
Balasubramanian Thiagarajan
![Page 2: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/2.jpg)
drtbalu's otolaryngology online 2
Introduction
Highly complex and variable anatomy Variations – impact on drainage Efficiency of muco-ciliary clearance –
relationship to morphology of frontal sinus
![Page 3: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/3.jpg)
drtbalu's otolaryngology online 3
Embryology
![Page 4: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/4.jpg)
drtbalu's otolaryngology online 4
Embryology - contd
Continuation of embryonic infundibulum, frontal recess superiorly
Upward migration of anterior ethmoid air cells
Penetration via inferior aspect of frontal bone between the two tables
Pneumatization 2-9 years Complete – 9 years
![Page 5: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/5.jpg)
drtbalu's otolaryngology online 5
Frontal sinus drainage
Expands into the diploic space of frontal bone from frontal sinus ostium
Each sinus grows independently of the other
Growth is dependent on ventilation, drainage, growth of surrounding sinuses and skull base
Drainage is hence highly variable
![Page 6: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/6.jpg)
drtbalu's otolaryngology online 6
Frontal sinus drainage - contd
Inferomedially into funnel shaped area (frontal sinus ostium)
Anterior wall of drainage channel is bounded by nasal beak
Ostium is oriented perpendicular to the posterior wall of the sinus at the skull base level
![Page 7: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/7.jpg)
drtbalu's otolaryngology online 7
Frontal beak
![Page 8: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/8.jpg)
drtbalu's otolaryngology online 8
Frontal sinus drainage pathway compartments
Drainage pathway is divided into superior and inferior compartments
Superior compartment is formed by union of adjacent air cells at the antero inferior portion of ethmoid bone
Size and shape of this component varies with the varying anatomy for fronto ethmoidal air cells
Superior compartment communicates with the inferior compartment
![Page 9: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/9.jpg)
drtbalu's otolaryngology online 9
Inferior component
This passage is really narrow This compartment is formed by ethmoidal
infundibulum / middle meatus This is dependent on the attachment of
uncinate process
![Page 10: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/10.jpg)
drtbalu's otolaryngology online 10
Inferior compartment
Inferior portion - infundibulum Inferior portion - infundibulum
![Page 11: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/11.jpg)
drtbalu's otolaryngology online 11
Attachment to lamina papyracea – inferior component formed by middle meatus
![Page 12: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/12.jpg)
drtbalu's otolaryngology online 12
Inferior compartment formed by infundibulum
![Page 13: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/13.jpg)
drtbalu's otolaryngology online 13
![Page 14: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/14.jpg)
drtbalu's otolaryngology online 14
Frontal beak
Frontal beak forms the floor of frontal sinus
![Page 15: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/15.jpg)
drtbalu's otolaryngology online 15
Frontal recess
Antero superior portion of ethmoidal air cell system
This is where the frontal bone pneumatization begins
Lateral wall is formed by lamina papyracea Medial wall is formed by vertical
attachment of middle turbinate Posterior wall is variable ? Bulla if it
manages to reach up to skull base
![Page 16: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/16.jpg)
drtbalu's otolaryngology online 16
Frontal recess
![Page 17: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/17.jpg)
drtbalu's otolaryngology online 17
Agger nasi
![Page 18: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/18.jpg)
drtbalu's otolaryngology online 18
Large bulla
Can obstruct frontal sinus outflow This area should be critically studied
during imaging Causes obstruction from behind
![Page 19: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/19.jpg)
drtbalu's otolaryngology online 19
Bulla
![Page 20: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/20.jpg)
drtbalu's otolaryngology online 20
Uncinate vs frontal sinus drainage
Uncinate – skull base attachment causes frontal sinus to drain into superior portion of ethmoidal infundibulum
Uncinate – attached to middle turbinate causes frontal sinus to drain into ethmoidal infundibulum
Uncinate – attached to lamina papyracea causes frontal to drain into superior aspect of middle meatus. Ethmoidal infundibulum ends in terminal recess
![Page 21: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/21.jpg)
drtbalu's otolaryngology online 21
Ethmoidal infundibulum
3 – d space Lateral – LP Anteromedial –
Uncinate Posterior - Bulla
![Page 22: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/22.jpg)
drtbalu's otolaryngology online 22Large agger cell causing narrowing of frontal recess
Frontal recess block
![Page 23: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/23.jpg)
drtbalu's otolaryngology online 23
![Page 24: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/24.jpg)
drtbalu's otolaryngology online 24
uncinate process attached to skull base. The frontal recess is seen between the agger nasi and uncinate process
![Page 25: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/25.jpg)
drtbalu's otolaryngology online 25
Scan showing uncinate process being attached to lamina papyracea. This causes terminal recess to form. Frontal sinus drains directly into middle meatus
![Page 26: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/26.jpg)
drtbalu's otolaryngology online 26
scan shows the uncinate process being attached to the middle turbinate. Note the presence of infundibulum between the bulla and the uncinate process. Frontal sinus is seen opening into the infundibulum
![Page 27: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/27.jpg)
drtbalu's otolaryngology online 27
Bent's classification of frontal cell variants
Type I: Single frontal recess cell above the agger
Type II: Tier of air cells above agger projecting into the frontal recess
Type III: Single massive air cell above agger expanding in superior direction
Type IV: Single isolated cell within frontal sinus. Difficult to visualize due to thin walls
![Page 28: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/28.jpg)
drtbalu's otolaryngology online 28
Type I & II frontal cell
![Page 29: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/29.jpg)
drtbalu's otolaryngology online 29
Type III
![Page 30: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/30.jpg)
drtbalu's otolaryngology online 30
Type IV
![Page 31: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/31.jpg)
drtbalu's otolaryngology online 31
Supraorbital air cells
Pneumatization of orbital plate of frontal bone
Posterior to frontal recess & lateral to frontal sinus
Sometimes can reach high up mimicking frontal sinus
![Page 32: Drtbalu's otolaryngology online1 Radiological anatomy of Frontal sinus Balasubramanian Thiagarajan.](https://reader036.fdocuments.in/reader036/viewer/2022062407/56649cbb5503460f9498315b/html5/thumbnails/32.jpg)
drtbalu's otolaryngology online 32
Thank you