The document discusses Functional Endoscopic Sinus Surgery (FESS). FESS is a minimally invasive procedure that uses an endoscope to access and treat the paranasal sinuses. It aims to restore sinus function by re-establishing ventilation and mucociliary clearance. Key steps in FESS include uncinectomy to remove the uncinate process, maxillary antrostomy to access the maxillary sinus, and ethmoidectomy to access the ethmoid sinuses. Proper identification of anatomical landmarks like the middle turbinate, uncinate process, and bulla ethmoidalis is important for successful FESS.

1. FUNCTIONAL ENDOSCOPIC
SINUS SURGERY
Dr. Smruti Ranjan Samal
P.G. STUDENT, VIMSAR

2. FESS- Functional Endoscopic Sinus Surgery is often a
non-invasive / minimal invasive surgical procedure
that discloses sinus air cells and sinus ostia by having
an endoscope. It restores the paranasal sinus
function by re-establishing the physiologic pattern
of ventilation & mucocilliary clearance
The term FESS was coined by Kennedy in 1985
Father of FESS is Prof Mesenklinger
Hirschmann 1st described use of primitive
endoscope to examine the maxillary sinus through
an oroantral fistula

3. FESS- The Functional Aspects:
1. Preserving normal structure
2. Removing only obstruction
3. Preserving mucosa
4. Restoration of function
Advantage over Open Sinus Procedure
1. Safe , minimally invasive, no cuts
2. Doesn’t disturb healthy tissue
3. Performed in less time with better management
4. No visible signs that surgery has been performed
5. Quick recovery

4. Balloon Sinuplasty :
o Acclarent introduced balloon sinuplasty system that utilized
a nonconformable balloon which was capable of creating
microfratures in the bone surrounding the drainage
pathways of the Frontal, Maxillary, Sphenoid sinus

5. Lateral wall
• Formed by bony, soft tissue & cartilage
• Bony –
– Ethmoid infundibulum & uncinate
– Perpendicular plate of palatine bone
– Medial plate of pterygoid process of
sphenoid bone
– Medial surfaces of lacrimal bones
and maxillae
– Inferior conchae

8. INFERIOR MEATUS:
Runs along the whole length of lateral wall.
Nasolacrimal duct opens in its anterior part. Largest
of all meatus
MIDDLE MEATUS
o Bulla ethmoidalis: Bulge produced by middle ethmoid cells
o Uncinate process: Superior extension of lateral nasal wall(
medial wall of mxillary sinus). Medial & inferior to Bulla

9. Infundiblum: Air passage connecting the maxillary sinus
ostium to middle meatus
Hiatus Semilunaris: Medially it communicates with middle
meatus. Laterally & inf it communicates with infundibulum
• Frontal sinus – Opens into the anterior part of hiatus
semilunaris
• Maxillary sinus – Opens into the posterior part of hiatus
semilunaris
• Anterior and middle ethmoidal cells – Opens into the
upper margin of bulla ethmoidalis

10. Superior Meatus
Limited only to posterior one third of lateral
wall. Posterior ethmoidal sinus opens into it.
Sphenoethmoidal recess
Above the superior turbinate. It receives the
opening of sphenoid sinus

11. SINUSES
• Air containing cavity in certain skull bones
• Develop as a diverticula/outpouching from the lat
wall of nose & extend into Maxilla, Ethmoid,
sphenoid and frontal bones
• Four sinuses – Maxillary, Frontal, Ethmoid (Ant &
Post) & Sphenoid

12. Maxillary Sinus - (Antrum of Highmore )
• Largest paranasal sinus
• Pyramidal in shape
• Base - towards lateral wall of nose
• Apex – towards zygomatic process of maxilla
• On average it has capacity of 14.75 ml (14-15)

13. Frontal Sinus
• Situated between the outer & inner table of frontal bone
• Asymmetrical
• Intervening bony septum which may be thin or deficiency
• The natural frontal sinus ostium is usually located in the
posteromedial floor of the sinus (most dependent part).
• It opens into the middle meatus
• The ethmoidal infundibulum can act as a channel for carrying the
secretions (and infection) from the frontal sinus to anterior ethmoid
cells and the maxillary sinus or vice versa.

14. FRONTAL RECESS
• The frontal recess is an hourglass like narrowing between the
frontal sinus and the anterior middle meatus through which the
frontal sinus drains.
• The frontal recesses are the narrowest anterior air channels
and are common sites of inflammation

15. AGGER NASI CELL
It is present Anterior, lateral, and inferior to the
frontal recess .
It is aerated and represents the most anterior
ethmoid air cell, usually lying deep to the lacrimal
bone.
It usually borders the primary ostium or floor of
the frontal sinus.
its size may directly influence the patency of the
frontal recess and the anterior middle meatus.

16. Sphenoid sinus
• Occupies the body of sphenoid
• Right & left, seperated by a
thin strip of bony septum (like
frontal sinus)
• Ostium opens into spheno
ethmoidal recess

17. ETHMOID SINUS
• Thin walled air cavities in the lateral masses of the ethmoid bone
• Varies from 3 – 18
• Occupy the space between the upper third of the lateral nasal wall
and the medial wall of orbit
• Clinically divided into anterior ethmoidal air cells & posterior
ethmoidal air cells, by basal lamella (lateral attachment of middle
turbinate to lamina papyracea)

18. Relations
• Roof – formed by the anterior cranial fossa
• Lateral wall - orbit
• Medial wall – nasal cavity
• Thin paper like bony part of the ethmoid separating the air
cells from the orbit, called lamina papyracea, can be easily
destroyed leading to spread of ethmoidal infections into
the orbit
• Optic nerve forms a close relationship with the posterior
ethmoidal cells & is at risk during ethmoidal surgery

19. OSTIO MEATAL COMPLEX
• The ostiomeatal complex is the key anatomic area addressed by
endoscopic sinus surgeons.
• Blockage of the ostiomeatal complex prevents effective
mucociliary clearance, thus leading to a stagnation of secretions
and therefore leading to recurrent or chronic sinusitis.

20. OSTIO MEATAL COMPLEX
Maxillary sinus ostium
 ethmoid bulla
frontal recess
uncinate process
 infundibulum
hiatus semilunaris
middle meatus.

21. Pattern of Sinus Disease:
Sonkens’ Classification acc. to Middle meatus obstruction
1. OMC pattern- M,Ant.E,F
2. Infundibular – isolated obst of Eth. Infudibulum
3. Frontal recess inflammatory pattern
4. Sinunasal polyposis pattern
5. Sporadic pattern
Lund-Mackay Score radiologic score of chronic rhinosinusitis
Reading a CT scan of the PNS & OMC with assigns a score of
0- ( no abnormality)
1- (partial opacification)
2- ( complete opacification)
Each side graded separately. A combined score of 24 is possible

22. Gliklich and Metson System
Stage 0: <2mm mucosal thickening on any sinus wall
Stage 1: all unilateral disease or anatomical
abnormalities
Stage 2: bilateral disease limited to ethmoid or
maxillary sinuses
Stage 3: bilateral disease with involvement at least 1
sphenoid or frontal sinus
Stage 4 : Pansinus disease

23. Landmarks in FESS
Middle turbinate
Uncinate Process
Bulla Ethmoidalis
Sphenoid Ostium
Skull Base
Maxillary sinus ostium

24. MESSERKLINGER 5 LAMELLA
1st Lamella- UP
2nd Lamella- BE
3rd Lamella- Ground Lamella Basal
4th Lamella- Superior Turbinate
5th Lamella- Supreme Turbinate

25. Indication of FESS:
1. Chronic rhinosinusitis unresponsive to medical treatment
2. Recurrent acute sinusitis
3. Sinunasal polyposis
4. Mucocoele
5. Noninvasive fungal ball
6. Invasive fungal rhinosinusitis
7. CSF rhinorrohoea & anterior meningoencephalocele
8. Sinonasal Tumour
9. Severe Exopthalmus
10. NLD obstruction

26. Patient selection: Pre-operative assessment
 History
- Symptoms
- Medical treatment
- associated disease
 Examination of the Patient: (General & Local)
- Anterior rhinoscopy
- Septal deviation
- Turbinate hypertrophy
-Nasal airway Problem
- Nasal Endoscopy
- Character of mucosa & appearance of sinus drainage,
anatomical variations, structural abnormalities

27. • Radiological- Pre-operative X-rays, CT Scan(Gold Standard)
• Routine Blood Investigations
Key Points to be reviewed on Pre-operative CT SCAN
1. Disease: Extent and pattern & its clinical correlation
2. Bony integrity- (Erosion, expansion ,dehiscence )- skull base, lamina
papyracea, optic canal, carotid canal
3. Skull Base- Height, symmetry, slope of cribriform plate & fovea
ethmoidalis.
4. Maxillary Sinus- location & attachment of uncinate process to
medial orbital wall, pneumatisation & height
5. Ethmoid Sinus – location of AEA,PEA, height of post.ethmoid cell
6. Sphenoid Sinus- location of sphenoid ostium, septation & their
relation to carotid canal
7. Frontal Sinus- extent of pneumatisation, natural drainage pathway,
presence of ager nasi & frontal cell

28. Strategic Approach to FESS
1. Patient under general anaesthesia
2. Local vasoconstriction of the nasal cavity
3. Septoplasty and/or Rhinoplasty
4. Management of Middle Turbinate
5. Uncinectomy
6. Maxillary Antrostomy
7. Ethmoidectomy
8. Frontal Sinusotomy
9. Sphenoidectomy
10.Management of Inferior Turbinate

29. Nasal Preparation
 Preoperative oxymetazolline spray 3 times separated by 5-10min
 Once GA induced, nose is packed with topical epinephrine pledgets
 After draping , the nose is injected with a focus on MT in 3 loction
- Over the axilla at the junction of the Turbinate & lateral wall
- Inferomedially on the head of MT
- Posteriorly along the inferior aspect of Turbinate

30. A. Nasal Septal Surgery
If a DNS is present, obstructing the nasal cavity
& limiting the nasal airway or access to the
sinus cavities , a septoplsty is performed prior
to beginning the sinus surgery
B. Management of Middle Turbinate
 The anatomical variants of the middle
turbinate may cause middle meatal
obstruction like Choncha Bullosa where the
head of MT is enlarged.
 Resection of CB is done by incising the
inferior free border of MT along its length
and carrying the incision up to the neck.
The incision is further enlarged using
microscisor & the lateral half of the concha
is removed after elevating the mucosal flap
from the lateral bony wall

31. Types of Uncinate Process:
1. Acc. to superior attachment of uncinate
o Type I: UP bends laterally in its uppermost portion to be inserted into LP
o Type II: UP extends superiorly to the roof of the ETHMOID i.e. Skull Base
o Type III: Superior end of UP turns medially & attached to the MT
2. Medially bent uncinate process
3. Laterally bent uncinate process
4. Pneumatised uncinate process or Uncinate Bulla

32. C. Uncinectomy
 The MT is medialized using a Freer
Elevator by applying firm pressure
against the lateral aspect of the
upper part of turbinate.
 Uncinectomy begins with an incision
of the uncinate process at its
anterior attachment. The incision is
extended posteriorly and inferiorly ,
parallel to the upper of Hiatus
Semilunaris & towards the natural
ostium of maxillary sinus
 Uncinectomy exposes base of
Infundibulum & anterior wall of
Ethmoid bulla

33. Types of Uncinectomy:
A. Classical / Anterograde Technique:
Uncinectomy is performed via an incision with either the sharp end of freer
elevator or a sickle knife.
The incision should be placed at the most anterior portion of uncinate
process which is softer on palpation in comparison to firmer lacrimal bone
where also NLD located. Then by using blakeshly forcep the free uncinate
edge is removed . More prone for Orbital Fat Prolapse.
B. Swing door / Retrograde Technique:
Reverse cutting forceps or backbiting forceps were used in this technique.
Inferior free margin overlying the maxillary ostium is cut first & then incision
is made in the superior margin to form a flap from a flap from the uncinate
which is hinged on the anterior margin & can be moved with an elevator or
ball probe
This is followed by submucosal removal of the horizontal process of the
uncinate . More prone for NLD injury

36. D. Maxillary Antrostomy
 Initial identification of the natural ostium- anterior & inferior within
the middle meatus. Ostium usually at the same level as the inferior
margin of the middle turbinate,anterior to ethmoid bulla
 Opening is further enlarged posteriorly to the posterior fontanelle
with backward-biting punch forceps & anteriorly with upturned
Blakesley-Wilde ethmoid forceps
 Antrostomy should be placed just above the inferior turbinate & not
more anterior than the anterior end of the middle turbinate
 Polypoid tissue, diseased mucosa , mucous plug should be removed

38. Types of maxillary sinusotomy: (SIMMENS CLASSIFICATION)
o Type.I : Ostium is opened posteriorly to a limited extent(<1cm in D)
o Type.II : Ostium is opened posteriorly & inferiorly (<2cm in diameter)
o Type.III: Wide exposure of opening of ostium in all direction i.e.
anteriorly up to lacrimal crest, superiorly up to orbit, inferiorly to
inferior turbinate, posteriorly to level of posterior wall of maxillary
sinus

41. E. Ethmoidectomy
Maxillary sinus is a single cavity with distinct ostium but the ethmoid sinus consists of multiple
cavities of interconnected cells.
The basal lamella of MT separates ethmoid labyrinth to two distinct anatomical and physiologic
compartment.
 Anterior group of cells drains its secretion into infundibulum together with maxillary
& frontal sinuses
 Posterior group of cells drains their mucus into superior meatus
 Main anatomical landmark for ethmoidectomy is identification of Ethmoid Bulla
 Mucosa is dissected over the bony surface of Ethmoid Bulla
 The goal of anterior ethmoidectomy is complete exposure of anterior ethmoid cells

42.  Posterior ethmoidectomy is done if involvement of posterior comaprtment.
 After dissecting the anterior ethmoid cells ,the basal lamella of the
MT encountered. It is perforated medially & inferiorly.
 The posterior ethmoid cells are removed stepwise till the anterior
wall of the sphenoid sinus is exposed.
 The posterior ethmoid artery can be seen & landmarks the anterior
edge of most posterior ethmoid cells.
Imp:
a. Open the cells of anterior & posterior ethmoid region at their
lowest portion parallel to floor of nasal cavity, i.e. parallel to skull base
b. Dissection along the roof of the ethmoid bone most safely
executed in a Posterior to Anterior direction after the ethmoid sinus
opened in an Anterior – Posterior course

44. F. Frontal Sinusotomy
Kuhn Classification of Frontal Recess & Frontal Sinus Cell
Agger nasi cell
Supraorbital ethmoid cell
Frontal cell
Type 1 – Single Frontal cell above agger nasi cell
Type 2- Tier of cells in FR above agger nasi cell
Type 3- Single massive cell pneumatising cephalad in to Frontal S
Type 4- Isolated cell in Frontal Sinus
Frontal Bulla Cell
Suprabullar cell
Interfrontal sinus septal cell

45. Acc.to Draf Endonasal Frontal Sinus Drainge
Type I: Simple drainage
Type II a/b: Extended drainage
Type III: Endonasal Median Drainage= Endoscopic modified Lothrop pro

47. Type III: Endonasal Median Drainage= Endoscopic
modified Lothrop procedure
It is done by either
A. Primary lateral approach: if previous ethmoid
work incomplete & MT is intact as land mark
B. Medial approach: if ethmoid has been cleared
and/or if the middle turbinate is absent. This
begins with resection of perpendicular plate of
nasal septum

48. When the type III drainage is technically not possible
(anterior-posterior diameter of the frontal sinus less than 0.8
cm) or has failed, osteoplastic frontal sinus obliteration
must be considered
Indications of Osteoplastic Frontal Sinus Obliteration:

49.  Intranasal frontal sinusotomy is the potentially dangerous procedure
as it is close to the Orbit & Skull base
 Imp. Landmark is anterior ethmoid artery which is posterior to frontal recess
 To visualise the frontal recess area, it is necessary to remove the ager nasi cells.
Then the frontal recess is enlarged using sharp curette to break down anterior
ethmoid cells, the spina nasalis frontalis (nasofrontal ‘’beak”)

51. G . Sphenoidotomy
 The sphenoid sinus can be opened safely 10 mm above the choana
just lateral to the midline septum at the rostrum of the sphenoid.
 After identification of ostium the opening enlarged in lateral &
inferior direction. Initial opening is made with Straight Blakesley
forceps.
 If the entire anterior wall of the sinus is thick & ostium is not
visualised , an angulated hand piece with extra long diamond burr is
used to make opening in ostium area
 Optic nerve & carotid artery located in lateral & posterior wall. Sella
turcica situated medial & superior to the sinus & cavernous sinus
located laterally
 Roof of sphenoid sinus is extremely thin- potential risk of a CSF leak

55. H. Management of inferior turbinate
After taking care of septal deviation & parnasal sinus diease , last step is to treat IT
hypertrophy
 Long nasal speculum is introduced along the IT & with endoscopic view the
posterior third of turbinate is removed after being retracted medially with
straight Blakesley forceps.
 The anterior & middle third of HIT treated with Radio Frequency Thermal Ablation

56. Post-operative Care
o Nasal packing: Packing used to control bleeding ,prevent adhesions
o Regular analgesia & vitals are carefully monitored
o Observe for epistaxis, headache, orbital swelling, diplopia, reduced
visual acuity
o Remove nasal packing after 48 hours
Post-operative Ambulatory Care
o Antibiotics are not routinely prescribed
o Instruct not to blow nose hard for at least 48 hours
o Commence topical decongestants for 5 days & saline spray for
6weeks
o Suction toilet of the nose
o Recommence long-term nasal steroids after 1 wk in nasal polyposis
o Decrust the nose with a rigid endoscope if necessary

57. Complications :
Minor : Major:
Orbital- Orbital -
orbital emphysema Orbital hematoma
orbital ecchymosis Optic nerve injury
Nasolacrimal Duct Injury(epiphora) CSF fistual
Disturbance in olfaction Brain laceration
Dental pain/lip pain or numbness Haemorrhage
Ethmoid arteries
Internal carotid artery
Cavernous sinus fistula
Sphenopalatine artery

58. Factors avoiding complications:
 Proper use of nasal endoscope
 True cut instrument
 Imaging
 Image guidance
 Through knowledge of anatomy
 Hypotensive anaesthesia
Complications are common in:
 Revision FESS
 Surgery for nasal polyposis
 Type 3 kerio skull base
 Anatomical variants like asymmetrical low lying ethmoid roof

59. Some rules about FESS
1. Avoid MT recessection
2. Avoid classical uncinectomy
3. Don’t be a destroyer of nose
4. Retain Bulle till the very end
5. Proceed from less vascular area to more vascular one
6. Controlled hypotensive anaesthesia
7. Stop surgery when bleeding is excessive
8. Avoid nasal packing
MESS: Marsupialization Endoscopic Sinus Surgery
When a functional procedure can’t be performed , an
attempt made to create a single ethmoid cavity in which
frontal, maxillary, sphenoid can adequately drain