This document provides an overview of the anatomy and physiology of the nose and paranasal sinuses. It describes the nasal cavity boundaries and septum. It discusses the maxillary, ethmoid, frontal, and sphenoid sinuses as well as the ostiomeatal complex. Causes of nasal obstruction, sinusitis, epistaxis, and sinus tumors are summarized. Treatment approaches for various nasal and sinus conditions are also outlined.

1. The Nose and paranasal
Sinuses
Dr Samer Serhal
E.N.T. MD

2. The nasal cavity
 Twin passages divided by a thin midline
vertical septum.
 The boundaries of each nasal cavity are:

3. Boundaries of nasal cavity
 Medially: septum
 Inferiorly: hard palate
 Laterally: medial wall of maxillary and
ethmoid sinus
 Superiorly: cribriform plate

4.  Blow out fracture in boxers: inferior rectus
muscle herniates--- cant move the orbit
 Inferior meatus (behind the inferior
turbinate): naso lacrimal duct opens in it
 Middle meatus: openings of maxillary,
ethmoidal and frontal sinus open in it

5. The nasal septum
 Maxillary crest and spine inferiorly
 Quadrilateral cartilage antero-inferiorly
 Vomerine bone postero-inferiorly
 Perpendicular plate of ethmoid superiorly

7. Lateral nasal wall

8. Vascular anatomy
 The arterial supply to the nose ( lateral
wall and septum ) is derived from both
the internal carotid ( the anterior and
posterior ethmoidal branches of the
ophthalmic artery ) and the external
carotid ,the latter being predominant).
 The terminal branches of these vessels
form a plexus on the anterior septum
known as little’s area.

9. Arterial Supply
1- From Internal carotid art: Anterior and
posterior ethmoidal arteries brs of the
ophthalmic artery
2- From Ext carotid art: Sphenopalatine art;
Greater palatine art; Superior labial br of facial
art; => + post ethmoidal art =Kisselbach’s
Plexus or Little’s area

10. Medial (septal) nasal wall blood
supply

11. Lateral nasal wall (blood supply)

12.  Anterior bleeding: in pediatrics, benign, (
control: flex the neck and close the nostrils)
 Post bleeding : adults, sphenopalatine
artery, harder to control

13. Nerve supply
 Olfactory nerve
 Trigeminal :ophthalmic and maxillary
branches

14. The paranasal sinuses
 Four separate groups of air filled
spaces which communicate with the
nasal cavities with at least one opening
or ostium.
 The maxillary and ethmoid sinuses are
present at birth, the frontal and sphenoid
sinuses develop later.

16. The maxillary sinus
 Volume is 1 ml at birth and enlarges to
15 ml in adults.
 The sinus boundaries are:
Sup: the orbital floor
Inf: the hard palate
Post: The pterygopalatine fossa
Ant-lat: The malar bone and maxilla
Med: The nasal cavity.
 The ostium opens beneath the middle
turbinate.

18. The maxillary sinus
 The growth of the sinus after the twelfth year
is related to an invasion of the alveolar
process after the eruption of the secondary
dentition.
 In adults the floor of the maxillary sinus is 5
mm inferior to the floor of the nasal cavity.
 The limits of the maxillary floor are usually
marked anteriorly by the first bicuspid and
posteriorly by a small recess posterior to the
roots of the third molar.

19. Ethmoid sinuses
 Anterior /posterior groups
 Boundaries : lamina papyracea , fovea
ethmoidalis ,cribriform plate
 Post sinus surgery risk: cribriform plate or
Ethmoid fracture  csf leakage, bleeding,
infection, orbital injury

20. Frontal sinuses
 Drainage via the frontal recess into the
middle meatus anteriorly
 Anterior and posterior table
 Can cause meningitis

21. Sphenoid sinuses
 Strategic position into the base of skull
Superiorly: Optic nerve and pituitary
Posteriorly: pons
Externally & laterally: cavernous sinus and
ICA
 Causes severe headache

22. The ostiomeatal complex
 Ethmoid infundibulum
 Hiatus semilunaris
 Drainage area for : anterior ethmoids
,maxillary and frontal sinuses
 The sphenoid and posterior ethmoids drain
into the sphenoethmoidal recess
 Edema ( e.g.allergy) ,inflammation ,nasal
polyps ,tumors ,structural anomalies (concha
bullosa and NSD) aid in the obstruction of
the OMC

23. Nasal obstruction
 Unilateral (foreign body) vs bilateral
 Intermittent (allergy) vs continuous
 Complete vs incomplete
 Nasal discharge/headache.
 Allergic manifestations (sneezing, clear
nasal discharge )
 Epistaxis (tumor)
 Association to environmental factors

24. Causes of nasal obstruction
 Nasal septal deviation (traumatic / growth)
 Septal perforation
 Inferior turbinates hypertrophy (allergy
,idiopathic ,chronic inflammation)
 Nasal polyps or tumors
 Choanal atresia or stenosis
 Adenoids hypertrophy
 Nasopharyngeal tumor
 Chronic sinusitis

25. Complication of
surgery: septal
perforation (whistling
bruit, obstruction)

26. NSD
 Cartilaginous , bony or both
 Traumatic or simply sec to growth
 SMR to relieve nasal obstruction if
symptomatic

27. Turbinates hypertrophy
 Allergic
 Associated with NSD
 Treatment medical : nasal steroids and
antihistamines if allergic
 Partial turbinectomy ,reduction by
cauthery or laser if not responding to tx
or non- allergic

28. Septal perforation
 Post-surgical
 Drug addiction
 Bleeding and crusting with altered air
flow will cause nasal obstruction and
occasionally sinusitis

29. Choanal atresia
 Emergency when bilateral
 Bony /membranous
 Partial or simply stenosis
 Unilateral can present in childhood or
adulthood

30. Sinusitis classification
 Acute /subacute/chronic
 bacterial vs fungual
 With or without polyps
 Eosinophilic hist. features

37. Acute sinusitis
 Definition: acute inflammation of the the sinus
mucosa ( the maxillary sinuses being the most
commonly affected).
 Mostly follows a viral URTI that causes edema
and obstruction of the sinus ostia and
paralysis of the mucosal cilia causing stasis of
mucus secretions and secondary bacterial
sinusitis( H. influenza ,M.catarrhalis
,S.pneumoniae.)
 Odontogenic infections.

38. Symptoms and signs of maxillary
acute sinusitis.
 Throbbing Pain of the cheek or upper teeth
made worse by coughing
 Fever (not usually present in chronic sinusitis)
 Tenderness over the cheeks
 CT or sinus xr ( not done routinely ) of the
maxillary sinus will help to evaluate the extent
and size of the sinus ,dental fragments ,apical
root abscess ,fungual balls ,mucosal retention
cysts….

40. Treatment of acute sinusitis
 Topical vasoconstrictors and systemic
decongestants will help sinus drainage.
 Antibiotics ( if suspecting odontogenic source :
penicillin, clindamycin , metronidazol or
amoxicillin/clavulonic acid are the most
effective.
 When patient fails to improve , maxillary sinus
puncture ( canine fossa or inferior meatus ) for
obtaining cultures and sinus wash might be
done

42. Chronic sinusitis
 Considered chronic when sinus syxs last
more then 6 to 12 weeks.
 Critical to the management is a
thorough search for underlying cause:
nasal allergy , polyps ,sinus f.b.( tooth
piece )…..

44. Fungual sinusitis
 Aspergillus ,candida and mucormycosis
species
 Aspergillus usually in a noninvasive
saprophytic form ,might present in an
allergic fungual form (expand sinus
borders ),invasive form in
immunocompromised hosts .
 Mucormycosis deadly disease in poorly
controlled diabetic patients

45. Sinus headache
 Maxillary : site of pain over antrum ,roots of
the upper molars.
 Ethmoid : site of pain is periorbital (anterior
),vertex ,behind eye (posterior).
 Frontal : forehead or above eyes.
 Sphenoid : pain referred to frontal ,temporal ,or
occipital area ,retro orbital or vertex pain.

46. Sinus neoplasms
 Rare tumors ( less then 1% of all neoplasms)
and when malignant have a hi mortality
because diagnosed late at an advanced stage.
 Benign tumors :
adenoma,papilloma,osteoma,angiofibroma,heman
gioma,fibrous displasia…
 Malignant tumors: The most common is SCC.
Adenocarcinoma, salivary gland tumors ,adenoid
cystic carcinoma , olfactory neuroblatoma ,
angiosarcoma ,rhabdomyosarcoma …

47.  The majority of malignant tumors ( 60% )
arise in the maxillary sinus antrum
area.30% arise in the nasal cavity and
10% in the ethmoid sinuses.
 Clinical features of maxillary sinus
malignant tumors depend on the
direction of tumor growth.

48. Symptoms and signs of maxillary
sinus tumors

49.  Investigation: obtaining a biopsy , better by
nasal rout then by caldwell-luc approach in
order not to compromise natural barriers for
tumor spread.
 C.T. Scan
 Management is by radiotherapy , partial
maxillectomy , total maxillectomy followed by
radiotherapy depending on the size of the
tumor.
 The maxillectomy defect is filled with a
modified dental plate or obturator.

50. Epistaxis
 Definition: bleeding from the nose .
 Most episodes are minor but occasionally life
threatening hemorrhage may occur.
 In 80% of cases bleeding comes from little’s area
although in older patients the bleeding pt is more
likely to be situated posteriorly.
 Bleeding sometimes go to the posterior oropharynx
and present as blood in the oral cavity.
 Occasionally it is difficult to determine the source of
the blood (nasal or gingival or lung ) especially when
pt present with bloody sputum (nasal endoscopy , good
oral exam , cxr and sinus XR or CT will help the
physician)

51.  In children and young adults spontaneous
bleeding from little’s area is common.
 In elderly pts hypertension is often associated
with epistaxis and the bleeding tends to arise
far back (posterior).
 Bleeding may be present as blood per nostrils
or might trickle posteriorly into the throat and
present in the oral cavity or vomitted.

53. Management
 Press the tip of the nose.
 Constrict the nasal mucosa with topical
adrenaline solution.
 Cauterize the bleeding point.
 Anterior nasal packing.
 Posterior nasal packing.