1. Diseases of the paranasal sinuses Ehab ZAYYAN, MD, PhD

2. Embryology Ethmoid sinuses: 0- 12 y Frontal sinus: 6- 20 y
Maxillary sinus: y y
Radiology: 1 year
Sphenoid sinus: 3- 20

3. Anatomy of the sinuses Maxillary sinus (Antrum of Highmore)
The largest paranasal sinus
10-20 cc in volume
Floor: alveolar process
Roof: orbital floor
Medial wall: bony+ membranous (ant and post fontanelles)
Ostium opens in the middle meatus, in the lower paret of the ethmoid infundibulum.
Accessory ostia may be found in the ant or post fontanelle in 25% of people (clinical importance!!)

4. Anatomy Ethmoid Sinuses lamina cribrosa (cribriform plate)
Crista galli
Perpindicular lamina
Lamina paperacea
Air cells: (average: 9) in each side

5. Relations of the ethmoids:
Anterior: orbit and nasolacrimal duct
Posterior: sfenoid sinus, orbital apex, optic nerve
Lateral: orbit
Superior: skull base

6. Anatomy Anterior ethmoid cells drain into the middle meatus
Ground lamella (attachment of the middle turbinate to the lat nasal wall)
Posterior ethmoid cells drain into the upper meatus

7. Anatomy Uncinate process
Hiatus semilunaris: curved space between the uncinate and ethmoid bulla. Entrance to the ethmoid infundibulum.
Ethmoid infundibulum: the drainage site of the maxillary, frontal, anterior ethmoid cells.
Bulla ethmoidalis: the most constant and the largest anterior ethmoid cell
Ground lamella
Posterior ethmoid cells (eg. Onodi cell)

8. Frontal Sinus Paired asymmetric sinuses
Absent unilaterally in 12% and bilaterally in 5%
Drainage:
Frontal ostium→ Nasofrontal duct →Frontal recess →Ethmoid infundibulum

9. Sphenoid sinus Lies in the center of the head
- Above : optic nerve and pituitary gland
- Laterally: orbital apex, cavernous sinus, carotid arteries
- Posterior: basillar artery, pons
- Inferiorly: nasopharynx
Drainage: sphenoethmoidal recess into the superior meatus

10. Histology
The nasal vestibule is lined with stratified squamous epithelium with vibrissae, sweat glands, and sebaceous glands.
The sinonasal mucous membrane is pseudostratifed, columnar, ciliated epithelium (respiratory epithelium.
Olfactory epithelium.

11. The sinus mucosa compared to nasal mucosa:
Thinner
Shorter epithelium
Basal membrane is very thin
Less goblet cells
Very few seromusinous glands in the submucosa
Lamina propria is is very thin and firmly adherent to the periostium

12. Physiology The mucous membrane consists of two layers:
Gel layer: thick viscous elastic layer
Sol layer: serous layer between the cilia
Daily mucous secretion: 600 – 1800 cc
Contains a lot of substances mainly lysozymes and immunoglobulins.

13. Ciliary movements:
cilia/ cell
8-20 beat/ second
The movement is towards the natural ostium not towards the gravity.
For maximum ciliary activity:
Humidity: >85%
Temperature: degree C
pH: 7- 8

14. Normal ventilation
Normal drainage
Ciliary movements

15. Factors negatively affecting the mucociliary activity
Dryness of air
Cigarette
Temperature
Hypoxia
Hypercapnia
Hypertonic/ hypotonic fluids
Dehydration
pH changes
Cystic fibrosis
Primary ciliary dyskinesia
Drugs ( phenylphrine, adrenaline, lidocaine, atropine, antihistaminic).
Infections
Anatomic obstruction (septum, turbinate,..)
Foreign body
Nasal polyps

16. secretions in the sinuses
Hypoxia ↓
Vasodilatation Ciliary dysfunction Mucous gland
↓ dysfunction
↓ Stasis ↓
Transudation Accumulation of thick ← thick fluid
secretions in the sinuses
Bacterial growth

17. Osteomeatal complex
The most commonly infected structure in the sinuses
Can be obstructed and inflammed easily with even minimal edema
Can not be examined by anterior rhinoscopy but with endoscopy
Can not be evaluated by conventional radiology but needs CT

18. Obstruction of the osteomeatal complex
Anatomic variations
Foreign body
Mucociliary dysfunction
Allergy
Infections
Local inflammation ↓
Obstruction of the osteomeatal complex
Sinusitis

19. Osteomeatal complex obstruction, ↓
Decreased ventilation of the sinuses,
Decreased drainage of the sinuses
pO2 decrease, pCO2 increase, mucous stasis
Inflammation and viscous mucous, ciliary movement slowing
Stasis and proteolytic enzymes
Ciliary damage
Anaerobic microrganisms
More damage……

20. Sinonasal imaging Plain sinus radiographs: Sinus opacifications
Air-fluid level
Mass
Fractures

21. Water view Best for maxillary sinuses and orbital rims
Blow-out fractures

22. Caldwell view
Best for frontal sinus

23. Lateral view
Best for sphenoid sinus and frontal sinus

24. Submental vertex (basal) view
Zygomatic archs
Sphenoid sinus
Lateral walls of the orbit

25. Computed tomography Excellent views of the sinuses Coronal section
Best for osteomeatal complex and ethmoidal disease

26. MRI Excellent soft tissue definition Neoplastic disease evaluation
Fails to demonstrate bone
Expensive
Claustra- phobia

27. Pathophysiology of sinusitis
4 stages
Initial phase
Ostium obstruction phase
Bacterial phase
Chronic phase

28. 1.Initial phase Edema and hyperemia of the sinus mucosa
Transudate accumulation and serous fluid
Reversible
If the ostium is not obstructed it resolves spontaneously

29. 2. Ostium obstruction phase
Sinus drainage and ventilation decreases
The secretion becomes thicker and more viscous
Ventilation decreases more, pO2 pressure ↓, CO2 ↑
A good media for anaerobes develop

30. 3. Bacterial phase Rapid bacterial growth Anaerobic bacterial growth
Local inflammation
Viscosity increases
Ciliary activity decreases
If not treated chronic changes start

31. 4.Chronic phase Immune activities stop Irreversible changes occur
Mucosal destruction
Ciliary activity stops
The irreversibla changes usually affect some of the mucosa, so if surgery (FESS) is performed, the rest of the mucosa can be saved and start functioning….

32. FESS
The target of Functional Endoscopic Sinus surgery (FESS) is to remove the pathology of the osteomeatal complex to maintain normal ventilation and drainage to the sinuses.
Anatomic variations (septal deviation, concha bullosa, uncinate variations, ….)
Foreign body
Nasal polyps
Chronic sinusitis

33. Sinusitis Acute sinusitis - acute - subacute - recurrent acute
Chronic sinusitis
- recurrent with acute exacerbations
Fungal sinusitis
- acute invasive (fulminant)
- chronic indolent
- Mycetoma (fungus ball)
- Allergic fungal

34. Acute sinusitis Preceding viral infection is the most common cause
Bacterial etiology: S. pneumonia, H. influenza, M. catarrhalis, S. aureus, S. pyogens
Anaerobic (more common in chronic)
Nosocomial (gram negative bacteria)

35. Symptoms Nasal obstruction Mucupurulent nasal discharge
Headache/ facial pain (eye, teeth, ears, vertex)
Postnasal discharge
Cough
Halitosis
Sore throat
Fever

36. Examination Nasal congestion and discharge Post-nasal discharge
Tenderness over the sinuses
Transillumination

37. Radiology
Plain x- rays: opacity/ air- fluid level in the maxillary, sphenoid, frontal
CT: for the ethmoid (not indicated for acute cases)

38. Cultures From nasal discharge is unreliable
From the middle meatus are 70% correlated
Sinus puncture is the best.
Not routinely indicated.

39. The diagnosis of acute sinusitis is mainly by history and physical examination.

40. Treatment Antibiotics: (10- 14 days) Amoxicillin
Trimethoprim- sulfamethaxazole
Amoxicillin- clavulonic acid
Cefuroxime and second generation cefalosporins
Clarithromycin

41. 2. Oral decongestants
3. Local decongestants (3- 5 days)
4. Mucolytics
5. Antihistaminics
6. Nasal saline irrigation
7. analgesics/ anti-inflammatory
Sinus puncture: in very painful conditions and in non- responsive cases.
Frontal sinusitis: close follow up and iv therapy if needed.

42. Pediatric sinusitis Can be confused with URTI Rhinosinusitis
URTI symptoms > 5- 7 days. More severe symptoms and high fever.
Recurrent sinusitis: 3 or more attacks in 6 months or 4 or more in one year
Chronic sinusitis: persistence of symptoms more than 3 months

43. Underlying factors for recurrent/chronic sinusitis in periatric population: Allergy, passive cigarette smoking, kindergarten, adenoid vegetation, immunodefeciency, immotile cilia syndrome, cystic fibrosis.
Therapy: treat the underlying factors, medical therapy, surgical therapy.

44. Chronic sinusitis Persistent signs and symptoms beyond 8 to 12 weeks.
Mostly headache, chronic nasal obstruction, postnasal discharge.
Microbiology: common m.o. + anaerobes
Diagnosis: paranasal sinus CT
Treatment: 4 weeks second line antibiotics+ coverage for anaerobes (Metronidasole, clindamycin)
Usually needs surgical intervention

45. Acute fulminant (invasive)fungal sinusitis (Mucormycosis)
Rapidly progressive disease caused by family of Mucoracea: Rhizopus, Mucor, Absida. Less commonly due to Aspergillus species.
Occurs only in immunocopromized patients.

46. The fungi invade the blood vessel walls producing thrombosis, ischemic infarction, and necrosis and allowing spread of the disease.
The necrotic tissue provides ideal medium for fungal growth.
Patients are acutly ill, fever, lethargy, facial pain.
Examination: dark, necrotic turbinates and septum. Black facial necrosis and perforations of the septum and the palate.
Can invade the brain, the orbit and other vital structures.

47. Diagnosis: staining and cultures, CT, MRI.
Treatment:
Control of the underlying disease (DM…)
Radical debridement of all necrotic tissue.
IV amphotericin B for several months.

48. Chronic indolent fungal sinusitis
Endemic in hot dry areas like Sudan and India
Mainly by Aspergillus
Immunocompetent non-atopic patients
The same symptoms of chronic sinusitis
Slowly progressive invasive disease causing bone necrosis and chronic granulomatous infiltrate.
Diagnosis: demonistration of tissue invasion
Treatment: surgical removal + antifungal agents

49. Mycetoma (fungus ball)
Chronic non-invasive fungal infection. Usually affects a single maxillary sinus.
Immunocompetent nonatopic hosts.
Aspergilloma (caused by aspergillus)
Treatment: surgical removal.

50. Allergic fungal sinusitis
5 to 10% of chronic sinusitis cases
Atopic young adults/ adolescents with history of recurrent sinusitis and surgeries.
Nasal polyposis and positive skin tests are common
Rubbery green/ brown mucoid discharge and nasal polyps.
Staining of mucous: extramucosal hyphae, eosinophils, Charcot- Leyden crystals (Allergic mucin)
IgE can be elevated, positive fungal skin test

51. Allergic mucin

52. CT: unilateral involvement of multiple sinuses, bony erosions, metalic density of the mucous
Treatment:
Antibiotics
Steroids
Antifungals
FESS

53. Sinobronchial syndrome
25% of patients with nasal polyps develop asthma and vice versa.
Bronchial asthma and sinusitis are manifestations of the same underlying respiratory system disorder.
Bronchial smooth muscles↔ nasal mucosa venous sinusoids
Causes of asthma in chronic sinusitis
Nasal obstruction
Postnasal drip
Reflex bronchospasm (trigeminal vagal reflex)

54. Samter syndrome
Bronchial asthma
Nasal polyposis
Aspirin intolerence

55. Complications of sinusitis 1. local complications
Mucocele
Primary mucocele (mucous retention cyst): due to obstruction of the minor salivary glands and usually seen in the maxillary sinus. Silent.
Secondary mucocele: due to sinus ostia obstruction. Most commonly in the frontal sinus. Slow growth, bony erosions. Expand in the orbit and the cranial cavity.

56. Osteomyelitis
Most frequently in the frontal bone
Erosion through the anterior wall and development of subperiosteal abcess produces forehead swelling called Pott`s puffy tumor.
Intracranial extention may happen.
Treatment: iv AB + debridment

57. 2. Orbital complications
Preseptal cellulitis
Orbital cellulitis
Periorbital abcess
Orbital abcess
Cavernous sinus thrombosis

59. 3. Intracranial complications
Meningitis
Epidural abcess
Subdural abcess
Brain abcess

60. Surgical management of sinusitis
Traditional sinus surgery
Caldwell- Luc operation
Nasal antral window
Intranasal ethmoidectomy
External ethmoidectomy
External frontoethmoidectomy
Osteoplastic frontal sinus surgery
…….

61. Functional endoscopic sinus surgery (FESS)
Indications:
Chronic sinusitis
Polyposis
Mucocele
Fungal sinusitis
Benign tumors
CSF rinorrhea
Orbit decompression (Graves disease)
Optic nerve decompression
DCR (dacrocystorhinostomy)
Pitiutary adenoma

62. Complications:
Hemorrhage
CSF fistula
Orbital injury
Lacrimal system injury

64. Benign masses and tumors
Nasal polyps
Sinunasal papilloma
Hemangioma
Juvenile nasopharyngeal angiofibroma
Osteoma
Fibrous dysplasia

65. Malignant SCC (80%) Salivary gland tumors (adenoidcystic CA) Sarcoma
Malignant melanoma
lymphoma