CT SCAN PARANASAL SINUSES- NOTES
Clinical History:
Technique: Axial multidetector slices were performed through the paranasal sinuses without intravenous
contrast administration. Multiplanar reformats were done.
Comparison:
SUMMARY:
DETAILS:
Nasal cavity
Septal deviation:
Carillaginous part (anteriorly)
Bony part:
- Perpendicular plate of ethmoid (superiorly)
- Vomer (inferiorly)
Septal perforation or apparent ulceration: None
Turbinates (superior, middle, inferior): Normal morphology
Concha lamella
(pneumatisation of vertical lamella of middle turbinate above and medial of concha bullosa)
Concha bullosa (pneumatisation of middle turbinate)
Meatuses: Patent
Nasal mucosal thickening:
Olphactory clefts: Clear bilaterally
Anterior nasal spine: Intact
Nasolacrimal ducts: Normal bilaterally
Pyriformis aperture: Normal development.
Nasal bones: Continuous
Posterior nasal mass: None
Adenoids: No significant enlargement
Ethmoidal cells
-Right: Pneumatised, clear
-Left: Pneumatised, clear
-Laminae papyracea: Intact bilaterally
-Cribriform plate: Intact
-Olphactory fossae: No mass, Keros type
in depth
-Haller cells: Not defined
-Onodi cells: Not defined
Olphactory fossa (bilaterally between crista gally, horisontal and vertical lamellae of cribriform plate) olphactory nerves inside
Depth of olfactory fossa (measurements between the horisontal lamella and fovea ethmoidalis):
1) Keros type I - flat (1-3mm)
2) Keros type II - normal (4-7mm)
3) Keros type III - deep (8-16 mm)
Agger Nasi cell - pneumatised lacrimal bone (supero-lateral medial orbital wall). Most anterior and
lateral ethmoidal cells (prevalence 90%). If large, may compromise frontal recess
Haller cell - infraorbital cells (opposite to supraorbital cells) - see COR.
Onodi cell - (sphenoethmoidal): posteriormost ethmoidal, superolateral to sphenoidal, surrounding the
optic nerves (the clue to identify)
Fovea ethmoidalis of the frontal bone - on the lateral sides- roof of the ethmoid cavity (horizontal
extension of vertical lamella of cribriform plate
Horisontal lamella of the cribriform plate - midline
Vertical lamella of cribriform plate U-shaped or V-shaped, nesting crista gally \_|_/
Crista galli (the most median bony structure between horisontal and vertical lamellae of cribriform
plate)
Lamina papyrecea dehiscence: medial orbital wall herniation to ethmoidal sinus, containing fat and +/rectus medialis
Frontal sinuses
-Right: Pneumatised, clear
-Left: Pneumatised, clear
-Fronto-ethmoidal recesses: Patent bilaterally
-Suborbital air cells: Not defined
Fronto-ethmoidal recess: long funnel (see on SAG and COR) => hiatus semilunaris => middle meatus.
Medial to Agger Nasi cell
Additional frontal infundibular cells (alongside medial orbital walls: types I to IV from 8 o’clock to 11
o’clock on the left and mirror from 4 o’clock to 1 o’clock on the right). Type I - just above the Agger Nasi,
then II->III ->IV
Maxillary sinuses
-Right: Pneumatised, clear
-Left: Pneumatised, clear
-Osteomeatal units: Patent
-Orbital floors: Intact
-Infratemporal fossa: Unremarkable bilaterally
-Pterygopalatine fossa: Unremarkable bilateral
✓
Alveolar recess (floor)
✓Zygomatic recess (most lateral)
✓
Palatine recess (most posterior)
✓ Uncinate process (pneumatisation of uncinate process) of OMU
✓
Posterior wall => infratemporal fossa (lat.), pterygopalatine fossa (med.)
✓Spheno-palatine foramen (most medial aspect of the pterygopalatine fossa)
✓Pterygo-maxillary fissure (somewhere in infratemporal fossa)
OMU - drainage of maxillary, frontal and anterior ethmoidal cells
Ostium (funnel narrowing towards the OMU) =>
Infundibulum (continuation of ostium, narrowest part of OMU lumen) =>
Hiatus semilunaris (opening to middle meatus, where all outflow tracts meet)
Uncinate process (continuation of maxillary medial to the inferior wall of infundibulum)
Sphenoidal sinuses
-Right: Pneumatised, clear
-Left: Pneumatised, clear
-Spheno-ethmoidal recesses: Patent
Pneumatisation of anterior clinoid process (postero-lateral outpouching of sphenoidal sinus. NB! optic nerve just medial to it
Pneumatised pterygoid process of sphenoid (infero-lateral outpouching of sphenoid). On COR: vidian
canal in the infero-medial base of the outpouching, foramen rotundum at super-lateral base of
outpouching, pterygoid process are at the base
Spheno-ethmoidal recess (long separate funnel from sphenoid ostium; also added drainage from
posterior sphenoid cells) => superior meatus
Misc
Facial bones: No fracture or aggressive bone lesion
Other: None