PARANASAL SINUSES: Sagittal Anatomy with CT images


Histologic  parasagittal sections of adult PNS  were adopted from "Anatomy of the Paranasal Sinuses" by JB Anon, M Rontal and  SJ Zinreich, Thieme, New York, 1996.
Cadaveric sagittal CT images of PNS were taken by Dept. of Otolaryngology, Ajou University School of Medicine, June, 1997.

Kyung Shik Suh, M.D. 


The PNS-CT images of sagittal/parasagittal section are not possible in a live subject. Although lateral recontruction of the sagittal/parasagittal section can be obtained, but the image quality is not so good.
But the sagittal images of PNS are of great importence for the understanding the actual relationship between the basal lamellae of 5 ethmotrubinals and large sinuses, especially frontal sinuses.


A
AEA = anterior ethmoid artery 
AN = agger nasi
B = ethmoid bulla 
BL = basal lamella of MT 
CA = carotid artery 
FOC = foramen cecum 
FS = frontal sinus 
IM = inferior meatus 
IT = inferior turbinate 
MT = middle turbinate 
NB = nasal bone 
NC = nasal capsule 
NLS = nasolacrimal sac 
OG = olfactory groove 
ON =  optic nerve 
P = posteior ethmoid sinus 
SER = sphenoethmoidal recess 
SL = sinus lateralis 
SM =supeior meatus 
ST = superior turbinate 
STL = superior turbinate lamella 
SS = sphenoid sinus 
U = uncinate process

The frontal recess can be narrowed by adjacent structures such as uncinate process, bulla ethmoidlais or bulla lamella and pneumatized agger nasi cell.

The bulla lamella, if attached to the skull base far anteriorly, it can compromise the frontal sinus drainge by narrowing the frontal recess posteiorly.

The picture below shows a relationship between frontal sinus and bulla lamella. The posterior wall of bulla ethmoidlis is partly attached with basal lamella of middle turbinate superolaterally(B). But in more medial section(, the bulla lamella is fairly separated from basal lamella of middle turbinate(C).


B
AEA = anterior ethmoid artery
AN = agger nasi
B = ethmoid bulla 
BL = basal lamella of MT 
CA = carotid artery 
FOC = foramen cecum 
FS = frontal sinus 
IM = inferior meatus 
IT = inferior turbinate 
MT = middle turbinate 
NB = nasal bone 
NC = nasal capsule 
NLS = nasolacrimal sac 
OG = olfactory groove 
ON =  optic nerve 
P = posteior ethmoid sinus 
SER = sphenoethmoidal recess 
SL = sinus lateralis 
SM =supeior meatus 
ST = superior turbinate 
STL = superior turbinate lamella 
SS = sphenoid sinus 
U = uncinate process

C
AEA = anterior ethmoid artery
AN = agger nasi
B = ethmoid bulla 
BL = basal lamella of MT 
CA = carotid artery 
FOC = foramen cecum 
FS = frontal sinus 
IM = inferior meatus 
IT = inferior turbinate 
MT = middle turbinate 
NB = nasal bone 
NC = nasal capsule 
NLS = nasolacrimal sac 
OG = olfactory groove 
ON =  optic nerve 
P = posteior ethmoid sinus 
SER = sphenoethmoidal recess 
SL = sinus lateralis 
SM =supeior meatus 
ST = superior turbinate 
STL = superior turbinate lamella 
SS = sphenoid sinus 
U = uncinate process

 In our cadaver CT scan images(D, E), we could demonstrate the relationship between frontal sinus and bulla lamella. Also the agger nasi cell was clearly demonstrated. The frontal recess is narrowed by agger nasi cell anteriorly.

The bulla lamella was divided into two projections to the skull base and the suprabullar furrow was clearly demonstrated(D).


D
AEA = anterior ethmoid artery
AN = agger nasi
B = ethmoid bulla 
BL = basal lamella of MT 
CA = carotid artery 
FOC = foramen cecum 
FS = frontal sinus 
IM = inferior meatus 
IT = inferior turbinate 
MT = middle turbinate 
NB = nasal bone 
NC = nasal capsule 
NLS = nasolacrimal sac 
OG = olfactory groove 
ON =  optic nerve 
P = posteior ethmoid sinus 
SER = sphenoethmoidal recess 
SL = sinus lateralis 
SM =supeior meatus 
ST = superior turbinate 
STL = superior turbinate lamella 
SS = sphenoid sinus 
U = uncinate process

E
AEA = anterior ethmoid artery
AN = agger nasi
B = ethmoid bulla 
BL = basal lamella of MT 
CA = carotid artery 
FOC = foramen cecum 
FS = frontal sinus 
IM = inferior meatus 
IT = inferior turbinate 
MT = middle turbinate 
NB = nasal bone 
NC = nasal capsule 
NLS = nasolacrimal sac 
OG = olfactory groove 
ON =  optic nerve 
P = posteior ethmoid sinus 
SER = sphenoethmoidal recess 
SL = sinus lateralis 
SM =supeior meatus 
ST = superior turbinate 
STL = superior turbinate lamella 
SS = sphenoid sinus 
U = uncinate process

In the paramedian sagittal section(F,G), the distance between basal lamella of middle turbinate and bulla lamella is wider than lateral section. 

The same subject's coronal section shows the relationship of frontal recess to the agger nasi, uncinate process and bulla ethmoidalis.


F
AEA = anterior ethmoid artery
AN = agger nasi
B = ethmoid bulla 
BL = basal lamella of MT 
CA = carotid artery 
FOC = foramen cecum 
FS = frontal sinus 
IM = inferior meatus 
IT = inferior turbinate 
MT = middle turbinate 
NB = nasal bone 
NC = nasal capsule 
NLS = nasolacrimal sac 
OG = olfactory groove 
ON =  optic nerve 
P = posteior ethmoid sinus 
SER = sphenoethmoidal recess 
SL = sinus lateralis 
SM =supeior meatus 
ST = superior turbinate 
STL = superior turbinate lamella 
SS = sphenoid sinus 
U = uncinate process

G
AEA = anterior ethmoid artery
AN = agger nasi
B = ethmoid bulla 
BL = basal lamella of MT 
CA = carotid artery 
FOC = foramen cecum 
FS = frontal sinus 
IM = inferior meatus 
IT = inferior turbinate 
MT = middle turbinate 
NB = nasal bone 
NC = nasal capsule 
NLS = nasolacrimal sac 
OG = olfactory groove 
ON =  optic nerve 
P = posteior ethmoid sinus 
SER = sphenoethmoidal recess 
SL = sinus lateralis 
SM =supeior meatus 
ST = superior turbinate 
STL = superior turbinate lamella 
SS = sphenoid sinus 
U = uncinate process

H
AN = agger nasi
B = ethmoid bulla 
U = uncinate process

The vast complexity and variety of the ethmoid sinus could not be demonstrated in this page, but I hope above images to be helpful for understanding anatomy of the paranasal sinuses. May 18, 1998
 

REFERENCES

1.  Stammberger HR et al: Paranasal sinuses:Anatomic Terminology and Nomenclature. Annals of Otology, Rhinology and Laryngology Suppl. 167 - Oct 1995 Vol 104, No 10, Part 2, pp7-16

2. Anon JB, Rontal M and  Zinreich SJ: "Anatomy of the Paranasal Sinuses" , Thieme, New York, 1996.

go to self-test(click here), 33 questions about anatomy of the lateral nasal wall and PNS