Your SlideShare is downloading. ×
Paranasal Sinuses
By
Dr. Hassan M. Abouelkheir, DDs, MSc, PhD.
Normal Development & Variations
• They are 4 in number:
• 1- Frontal.. 2-Ethmoid.
• 3- Sphenoid. 4- Maxillary Sinus.
1- Frontal Sinus:
• Development
– Frontal bone at birth
– Age 5 or 6y.
• Structure
– Two cavities develop
separately and m...
2- Sphenoid Sinus:
• Development
Arise within the nasal
capsule (no pouch)
Age 3 begins to pneumatize
• Structure
– Volume...
3-Ethmoid Sinus (Ethmoid air cells):
• Development
– Present at birth
– Multiple connected
or separated
chambers.
– Variab...
Maxillary Sinus
• Development
– Present at birth as slit like.
– It grows laterally as it reach
infraorbital canal by 2nd ...
Function of Paranasal Sinuses:
• Humidifying and warming
inspired air
• Regulation of intranasal
pressure
• Increasing sur...
Diseases associated with maxillary sinuses:
• 1- Intrinsic diseases ; from within maxillary
sinus.
• 2- Extrinsic diseases...
Diagnostic imaging:
1- intraoral periapical .
2- Panoramic view.
3- Occipitomental (Water’s
view).
4- Lateral.
5- Submento...
I-Intrinsic diseases
Inflammatory diseases;
• 1- Mucositis:
• Normal sinus mucosa (1mm)
Is not visualized on
radiographs. ...
2- Sinusitis:
• Generalized inflammation of
paranasal sinus mucosa.
• Etiology :allergic, viral,
bacterial.
Classification...
Clinical features:
Acute sinusitis:→ nasal discharge ,
pain , tenderness to pressure or
swelling.
Sepsis, fever, malaise &...
Radiographic features:
• Uniform or polypoid
Thickening of sinus mucosa
with accumulation of
secretions inside sinus turni...
3- retention pseudocysts:
They may be due to ;
1- blockage of secretory ducts leading to
submucous secretion accumulation....
Radiographic features:
• Location: Single side or bilaterally.
• Best seen in panoramic view.
• It may arise from floor of...
4- polyps:
• It is thickened mucous membrane of
chronically inflamed sinus with irregular
folds called polyps.
• Clinical ...
5- Antrolith:
• It is deposition of mineral salts such as
calcium phosphate , carbonate &
magnesium a round a nidus which ...
Radiographic Features:
• Location: within maxillary
sinus.
• Periphery and shape: well
defined radiopaque mass
smoother ir...
6- Mucocele:
• Definition : it is expanding destructive lesion
that result from blocked sinus ostium due to
intrinsic or e...
Clinical features:
• It exert pressure on superior alveolar
nerves→ radiating pain.
• Swelling →anteroinferior aspect of M...
Radiographic features:
• Location : 90% in ethmoidal & frontal sinuses and
rare in maxillary sinus.
• Periphery & shape: t...
Neoplasms:
• Benign Neoplasms:
• 1- Epithelial Papilloma:
• Clinically; unilateral nasal obstruction ,
nasal discharge, pa...
Radiographic feature:

• Location: ethmoidal or maxillary sinus.
• Isolated polyp.
• Internal structure:
• Homogenous radi...
2- Osteoma
• Most common in males than
females 2:1 .
• 2nd, 3rd & 4th decade.
• Asymptomatic unless cause
destruction of s...
Malignant neoplasms:
• Squamous cell carcinoma:
• It consititutes 90% of cancers .
• Clinically : facial pain, swelling , ...
Radiographic features:

• Not specific.
• Radiopacity of sinus that develop sinusitis &
polyp formation.
• Location : fron...
Squamous cell carcinoma:


Extrinsic diseases involving the paranasal sinuses:

A- inflammatory lesions:
1- Localized Mucositis:
• It is a result o...
2- Periostitis:
• Inflammatory exudate of
the dental lesion diffuse
through cortical boundary
of sinus so elevate
perioste...
B- Benign odontogenic cysts and tumors:
1- Odontogenic cysts:
• Most extrinsic cysts are radicular
cysts, dentigerous then...
2- Odontogenic tumors:
• Benign odontogenic tumors (BOT) may cause
facial deformity, nasal obstruction & displacement
or l...
Radiographic features:
• Periphery & shape→ curved, oval or multilocular
shape with or without thin cortical border.
• Int...
Fibrous dysplasia:
• Craniofacial fibrous dysplasia, it is a
type of lesion at which cancellous bone
is transformed into f...
Radiographic features:
• Location: posterior maxilla is most
coomon site.
• Periphery: not well- defined and tend to
blend...
Traumtic injuries:
• Tooth roots may be fractured due
to trauma including iatrogenic
causes.
Clinical features:
• Displace...
THE END
THANKS
Upcoming SlideShare
Loading in...5
×

Paranasal sinuses

1,812

Published on

Radiology II
Forth Year

0 Comments
4 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
1,812
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
1
Comments
0
Likes
4
Embeds 0
No embeds

No notes for slide

Transcript of "Paranasal sinuses"

  1. 1. Paranasal Sinuses By Dr. Hassan M. Abouelkheir, DDs, MSc, PhD.
  2. 2. Normal Development & Variations • They are 4 in number: • 1- Frontal.. 2-Ethmoid. • 3- Sphenoid. 4- Maxillary Sinus.
  3. 3. 1- Frontal Sinus: • Development – Frontal bone at birth – Age 5 or 6y. • Structure – Two cavities develop separately and meet at midline with a septum. – They drain into nasal fossa via frontonasal duct. – Walls • Anterior vs. posterior • Related Structures – Frontal recess
  4. 4. 2- Sphenoid Sinus: • Development Arise within the nasal capsule (no pouch) Age 3 begins to pneumatize • Structure – Volume/variable pneumatization – Wall thickness – Position within the sphenoid • Relation to sella turcica • Sellar and postsellar relationships
  5. 5. 3-Ethmoid Sinus (Ethmoid air cells): • Development – Present at birth – Multiple connected or separated chambers. – Variability • Structure – Volume/shape – Roof – Lateral wall
  6. 6. Maxillary Sinus • Development – Present at birth as slit like. – It grows laterally as it reach infraorbital canal by 2nd year. – It may extend to zygomatic , alveolar or frontal – Biphasic growth – Level of the floor • Structure – Volume & shape – Walls, floor, roof
  7. 7. Function of Paranasal Sinuses: • Humidifying and warming inspired air • Regulation of intranasal pressure • Increasing surface area for olfaction • Lightening the skull • Resonance • Absorbing shock • Contribute to facial growth
  8. 8. Diseases associated with maxillary sinuses: • 1- Intrinsic diseases ; from within maxillary sinus. • 2- Extrinsic diseases ( odontogenic diseases). • Clinical features: • Feeling of pressure. • Pain on head movements. • Altered voice characteristics. • Regional paresthesia. • Swelling of facial structures.
  9. 9. Diagnostic imaging: 1- intraoral periapical . 2- Panoramic view. 3- Occipitomental (Water’s view). 4- Lateral. 5- Submentovertex. 6-Caldwell (15ºPA). 7- computed tomography (CT). 8- Magnetic resonance image (MRI).
  10. 10. I-Intrinsic diseases Inflammatory diseases; • 1- Mucositis: • Normal sinus mucosa (1mm) Is not visualized on radiographs. During inflammation it becomes thick 10-15 times and seen in radiographs. Mucosal thickening > 3mm is pathologic. • Clinically asymptomatic. • Radiographic feature→ slight radiopaque band parallel to sinus walls.
  11. 11. 2- Sinusitis: • Generalized inflammation of paranasal sinus mucosa. • Etiology :allergic, viral, bacterial. Classification: • Acute sinusitis→< 2 weeks. • Subacute sinusitis→ 2 weeks -3 months. • Chronic sinusitis→ > 3 months. • Pansinusitis→ sinusitis in all paranasal sinuses.
  12. 12. Clinical features: Acute sinusitis:→ nasal discharge , pain , tenderness to pressure or swelling. Sepsis, fever, malaise & elevated leukocyte count. Chronic sinusitis → a sequel of acute infection. There is inhibition of mucous outflow & there may be deviation of nasal septum & concha bullosa. It may be associated with allergic rhinitis, asthma, cystic fibrosis and dental infection.
  13. 13. Radiographic features: • Uniform or polypoid Thickening of sinus mucosa with accumulation of secretions inside sinus turning it‘s air radiolucency to radiopaque . • Water’s view showing the level of fluid and tilting of the head taking another view it shows changing in fluid level. • Management: • Decongestants , antibiotics or surgery.
  14. 14. 3- retention pseudocysts: They may be due to ; 1- blockage of secretory ducts leading to submucous secretion accumulation. 2- cystic degeneration due to inflammation . Clinical features: Asymptomatic. It may fill the sinus causing nasal obstruction. It may be ruptured due to change in pressure.
  15. 15. Radiographic features: • Location: Single side or bilaterally. • Best seen in panoramic view. • It may arise from floor of sinus or lateral walls. • More than one pseudocysts may develop. • They may fill the sinus space and becomes radiopaque. • Periphery and shapes: non- corticated smooth, dome-shaped radiopaque masses. • Effect on surrounding structures: no effect. No treatment is required.
  16. 16. 4- polyps: • It is thickened mucous membrane of chronically inflamed sinus with irregular folds called polyps. • Clinical features: it may destroy bone. • Radiographic features: • Polyp usually occurs with thickened mucous membrane lining. • It may cause bone displacement or lining that mimic benign or malignant neoplasm.
  17. 17. 5- Antrolith: • It is deposition of mineral salts such as calcium phosphate , carbonate & magnesium a round a nidus which may be extrinsic or intrinsic. • Clinical features: • small→ asymptomatic. • Large → sinusitis , nasal obstruction or facial pain.
  18. 18. Radiographic Features: • Location: within maxillary sinus. • Periphery and shape: well defined radiopaque mass smoother irregular. • Internal structure: • Radiopaque mass which can be distinguished from root fragment by anatomy of root and pulp canals.
  19. 19. 6- Mucocele: • Definition : it is expanding destructive lesion that result from blocked sinus ostium due to intrinsic or extrinsic inflammation, polyp or neoplasm. • Accumulation of mucous leads to transforming whole max.s. to cyst like cavity which may destruct the antral walls. • Infected mucocele → Pyocele or mucopyocele.
  20. 20. Clinical features: • It exert pressure on superior alveolar nerves→ radiating pain. • Swelling →anteroinferior aspect of Max. s. • Inferior expansion→ loosening of posterior teeth. • Medial wall expansion → deformity of lat. Nasal wall → nasal obstruction. • Orbital expansion → diplopia, proptosis.
  21. 21. Radiographic features: • Location : 90% in ethmoidal & frontal sinuses and rare in maxillary sinus. • Periphery & shape: turns sinus into circular cyst like shape. • Internal structure: uniformly radiopaque. • Effects on surrounding structures: • Boney expansion with wall destruction on the direction of lesion extension. • Treatment : Caldwell-Luc operation (surgical excision.
  22. 22. Neoplasms: • Benign Neoplasms: • 1- Epithelial Papilloma: • Clinically; unilateral nasal obstruction , nasal discharge, pain and epistaxis. • 10% incidence of associated carcinoma. • Radiographic feature: • Not specific . • Diagnosis is confirmed by histopathology.
  23. 23. Radiographic feature:
 • Location: ethmoidal or maxillary sinus. • Isolated polyp. • Internal structure: • Homogenous radiopaque mass of soft tissue density. • Effects on surrounding structures: • Bone destruction due to pressure erosion..
  24. 24. 2- Osteoma • Most common in males than females 2:1 . • 2nd, 3rd & 4th decade. • Asymptomatic unless cause destruction of surrounding tissue. • Radiographic feature: • Location in frontal and ethmoidal sinuses more than maxilary sinus. • Periphery and shape: lobulated or rounded well defined margins. • Internal structure: homogenous radiopaque.
  25. 25. Malignant neoplasms: • Squamous cell carcinoma: • It consititutes 90% of cancers . • Clinically : facial pain, swelling , nasal obstruction & a lesion in the oral cavity. • Medial wall destruction→ nasal signs & symptomes. • Floor of the sinus → dental signs & symptomes. • Lateral wall → facial & vestibular swelling. • Sinus roof → orbital signs. • Posterior wall → trismus.
  26. 26. Radiographic features:
 • Not specific. • Radiopacity of sinus that develop sinusitis & polyp formation. • Location : frontal & ethmiodal sinus more common than maxillary sinus. • Internal structures: soft tissue radiopaque lesion. • Effects on surrounding structures: destroying sinus walls → irregular radiolucent areas in surrounding bone.
 CT and MRI are superior for soft tissue extension. • Treatment: Combination therapy (surgery & Radiotherapy). • Poor prognosis.
  27. 27. Squamous cell carcinoma:
  28. 28. 
 Extrinsic diseases involving the paranasal sinuses:
 A- inflammatory lesions: 1- Localized Mucositis: • It is a result of inflammatory extension from dental origin (periodontal or periapical disease) beyond the cortical floor of the antrum . • It resolves after treatment of the cause. Radiographic features: • Homogenous radiopaque ribbon- shaped shadow that follow the contour of sinus floor.
  29. 29. 2- Periostitis: • Inflammatory exudate of the dental lesion diffuse through cortical boundary of sinus so elevate periosteium lining the sinus stimulating new bone formation at the root apex of involved tooth. • Radiographic feature: • Radiopaque line (similar to onion skin ) around apex of infected tooth.
  30. 30. B- Benign odontogenic cysts and tumors: 1- Odontogenic cysts: • Most extrinsic cysts are radicular cysts, dentigerous then odontogenic keratocysts. • They originate outside of sinus . The cortical border of the cyst is distinguished from cortical border of the sinus floor . • Cyst will displace the sinus cavity and fill the sinus space like internal retention psuedocyst which has no radiopaque line of that of odontogenic cyst. • Radiographic feature: • A cystic cavity define by corticated Border. Radiopacity of the cyst differ from that of sinus..
  31. 31. 2- Odontogenic tumors: • Benign odontogenic tumors (BOT) may cause facial deformity, nasal obstruction & displacement or looswning of teeth. • The aggressive growth pattern of some tumors as ameloblastomas require aggressive treatment to limit invasion to the base of the skull.
  32. 32. Radiographic features: • Periphery & shape→ curved, oval or multilocular shape with or without thin cortical border. • Internal structure→ coarse or fine septa. • Effects on surrounding structures → displacement of maxillary sinus . • Sinus walls may be eroded or thinned with displacement of teeth.
  33. 33. Fibrous dysplasia: • Craniofacial fibrous dysplasia, it is a type of lesion at which cancellous bone is transformed into fibrous tissue. • Dysplastic bone may obliterate maxilary sinus and displace of teeth without root resorption. • It is more common in chidern & young adults.
  34. 34. Radiographic features: • Location: posterior maxilla is most coomon site. • Periphery: not well- defined and tend to blend into the surrounding bone. Displacement of cortical bone but intact. • Internal structure: increased degrees of radiopacity according to stage of lesion. • Ground glass appearance in extraoral radiographs. • Orange peel appearance on intraoral views. • Effects on surronding structures: • Displacement of antral walls , elevating orbital floor, obstructing nasal fossa.
  35. 35. Traumtic injuries: • Tooth roots may be fractured due to trauma including iatrogenic causes. Clinical features: • Displaced roots in the sinus may cause sinusitis. Radiographic features: • Location → roots or fragments located near the floor of the sinus. Periphery and shape: • No change. Internal structure: radiopaque dental fragment + sinusitis. • No effect on surrounding structures. Treatment : surgical removal of remaining fragment.
  36. 36. THE END THANKS

×