This document provides an overview of the steps involved in primary sinus surgery via an endoscopic approach. It begins with a brief history of sinus surgery and then discusses preoperative assessment, including CT scans to evaluate sinus anatomy and disease patterns. The basic techniques of Messerklinger and Wigand are described. The key steps of the surgery are then outlined in detail, including uncinectomy, antrostomy of the maxillary sinus, anterior and posterior ethmoidectomy, sphenoid sinusotomy, and frontal sinusotomy when necessary. Throughout, anatomical landmarks and variations are discussed to guide safe dissection and avoid complications.

1. Dr. SANJAY MAHARJAN
PG, ENT-HNS
MTH, Pkr.
STEPS OF PRIMARY
SINUS SURGERY.

2. History of sinus surgery:
• 1675; Molinetti : approach via anterior wall to maxillary sinus
• 1890s; Caldwell, Spicer, and Luc : Caldwell-Luc procedures
• 1901; Hirschmann : conducted first endoscopic examination
of nose with a modified cystoscope
• 1950s : modern era of endoscopic sinus surgery evolved with
development of Hopkins rods
• 1978; Messerklinger: published his experience with ESS and
highlighted role of ostiomeatal complex
• Stammberger popularized it outside Germany and Austria

3. Indications:

4. Principles of FESS:
• Primary objective: restore paranasal sinus function by
reestablishing physiologic pattern of ventilation and
mucociliary clearance
• Goal : remove irreversibly diseased mucosa and bone, preserve
normal tissue, and widen true natural ostia of sinuses
• OMC is most often the primary target of ESS
• Mucosal lining of skull base, lamina papyracea, and sinus
cavities should be preserved
• Uninvolved sinuses should be left alone

5. PREOPERATIVE ASSESSMENT
• History:
Failure of symptomatic control with medical treatment
topical steroids and nasal irrigation for at least 4 weeks
• Examination:
Anterior rhinoscopy
Nasal endoscopy
Character of mucosa, appearance of sinus drainage
pathways, and presence of anatomic variations, structural
abnormalities, purulent drainage, and polyps

6. • Radiographic Assessment
CT
• Assess sinonasal anatomy and disease pattern so as to guide
surgery
• Coronal views : show the ostiomeatal unit and relationship of
brain and orbit with PNS
• Axial views : complement coronal views and are obtained for
severe disease in posterior ethmoid and sphenoid sinuses
• Sagittal views : evaluating frontal recess anatomy and slope
of skull base

8. • Variations that predispose inadvertent penetration of orbit
or anterior cranial cavity (Meyers and Valvassori 1998)
1. Lamina papyracea lying medial to maxillary ostium
2. Maxillary sinus hypoplasia
3. Fovea ethmoidalis abnormalities such as a low or sloping
fovea
4. Lamina papyracea dehiscence
5. Sphenoid sinus wall variations, such as septa attached to
carotid or dehiscence of carotid or optic nerve
6. Sphenoethmoid cells

10. MRI:
If bony dehiscence or erosion are present
Differentiate tumors from fluid within sinuses

11. PREOPERATIVE MEDICAL THERAPY
• Antibiotics and oral steroids may be started 7 to 10 days
before surgery
• Benefits of steroids included:
1. Decreased mucosal inflammation
2. Improved surgical field visualization
3. Decreased surgical time & bleeding in addition to
decreased disease recurrence rate, greater improvement in
symptoms, better postoperative results, and decreased
need for revision

12. BASIC TECHNIQUES
• Messerklinger technique :
Anterior-to-posterior approach
Starts with removal of the uncinate process to expose
infundibulum  removal of ethmoid bulla  exposure of
frontal sinus ostium & identification of roof of ethmoid
Once skull base identified, dissection continues posteriorly
with removal of remaining anterior & posterior ethmoid cells
 opening of sphenoid sinus
Ostium of maxillary sinus is then identified with use of a 30-
degree endoscope and is widened if necessary.

13. • Wigand’s technique :
Posterior-to-anterior approach for completing
ethmoidectomy
Begins with partial resection of middle turbinate  opening
of posterior ethmoid cells  removal of anterior wall of
sphenoid sinus
Once skull base identified, dissection is continued anteriorly
through posterior and anterior ethmoids
Major advantage of this technique is early exposure of skull
base

14. In practice, a combination of
these techniques is typically used

15. Steps:
1. Nasal Endoscopy.
• Landmarks
• Structural abnormalities
• Condition of mucosa
• Presence of any polyps or pus, and
• Any significant differences from preoperative examination
• In significant septal deviation, wider side approached first

16. 2. Middle Turbinate Medialization:
• Creates better view of middle
meatus
• Aggressive manipulation can lead
to destabilization of turbinate
and fracture at skull base
• Relaxing incision into middle
turbinate basal lamella avoids
uncontrolled destabilization and
increases operative space

17. 3a. Retrograde uncinectomy:
Uncinate process identified
with zero-degree endoscope
as a sickle shaped structure
with posterior free margin
Anteriorly, border is seen as
sharp line at junction with
frontal process of maxilla
(anterior maxillary line)

18. Ball-tipped probe is slid into
infundibulum behind
posterior free edge to
medialize uncinate process
into middle meatus, off
lamina papyracea
pediatric backbiter punch is
used to retrogradely incise it
in an axial plane betn
inferior one third and
superior two thirds

19. 3b. Anterograde Uncinectomy:
• Incision with sickle knife or freer
dissector to release it from its
anterior attachment to lacrimal bone
• Uncinate removed with through-
cutting instrument
• This technique carries greater risk of
injury to lamina papyracea and eye
• May be necessary with very everted
uncinate

20. 4. Middle meatal antrostomy:
• Removal of uncinate
process exposes
infundibulum lateral to it
• Maxillary sinus ostium is
elliptical
• Opens at 45-degree angle in
floor of infundibulum
• Lateral to lower third of
uncinate

21. • Accessory ostia are more
circular and are commonly
found within posterior
fontanelle
• Opening accessory ostium
of sinus and missing natural
ostium leads to mucus
recirculation and persistent
infection

23. • Antrostomy can be widened
inferiorly toward inferior
turbinate and posteriorly toward
posterior maxillary wall
• Biting anteriorly in natural
ostium is usu. unnecessary and
may damage nasolacrimal duct
• Disease in sinus can be removed
with curved endoscopic
instruments, a microdebrider, or
irrigation

24. • Haller cells are anterior
ethmoid air cells extending
into Maxillary sinus
• Can obstruct outflow tract of
maxillary sinus
• Must be removed when there
is pathology within maxillary
sinus

25. 5. Anterior Ethmoidectomy:
• Ethmoid bulla, largest cell of ant. ethmoid complex
• Usually first most prominent cell, seen as a bulge within
middle meatus
• If there is retrobullar space, this can be entered into, and
ethmoid bulla can be removed in retrograde fashion

26. • If no retrobullar space ethmoid bulla is entered along its
inferior and medial aspect
• lamina papyracea forms lateral wall of bulla, Mucosa should
be preserved on it
• Dissection should never be carried out medial to superior
vertical attachment of middle turbinate  carries risk of
penetrating cribriform plate and fovea ethmoidalis

27. • Depth of the olfactory fossa, graded according to Keros
classification:
I. Keros Type I  1 - 3 mm
II. Keros Type II  4 – 7 mm
III. Keros Type III  8 – 14 mm

28. • Dissection should continue posteriorly, until basal lamella is
identified

29. 6. Perforation of basal lamella:
The lateral insertion of middle
turbinate to lamina papyracea is
called basal lamella
It is posterior to bulla
ethmoidalis and separates
anterior from posterior ethmoid
air cells

31. Basal lamella opened at level
of superior aspect of
maxillary sinus ostium,
pointing sucker medially
towards septum

32. Straight curette passed
through opening in basal
lamella and opening
enlarged, first superiorly,
then laterally towards
lamina papyracea
Basal lamella opened until
entire free edge of superior
turbinate is visible

33. • Posterior Ethmoidectomy.
Posterior ethmoid cells open into superior meatus
To open posterior ethmoids, inferior and medial aspects of
vertical basal lamella must be removed
Post. ethmoidectomy proceeded in similar anterior-to-
posterior stepwise fashion, working up to sphenoid face and
skull base
Boundaries of post. Ethmoidectomy are between lamina
papyracea laterally and superior turbinate medially
Sphenoid face represents posterior limit of ethmoidectomy
dissection

34. • Onodi cell is posterior ethmoid (sphenoethmoidal) cell that
extends superior and often lateral to sphenoid sinus
• often closely related to optic nerve & carotid artery

35. 7. Sphenoid Sinusotomy:
• Anterior wall of sphenoid
sinus is usually convex,
toward surgeon, whereas
skull base is concave, away
from surgeon
• Sphenoid ostium lies at a
distance of 6.2 to 8.0 cm
(average, 7.1 cm) from nasal
spine, at an angle of 30 to
34 degrees to the floor

36. • Ostium of sphenoid sinus
can be approached
transethmoidally, lateral to
middle turbinate
• Either by
1. Entering sphenoid in
inferomedial part of most
posterior ethmoid, or
2. Through sphenoethmoidal
recess

37. • Inferior third to half of superior turbinate may have to be
removed
• Overresection is avoided to preserve olfaction
• Ostium widened by inserting a small curette or straight
forceps, with opening directed first medially and inferiorly

38. • Circumferential opening should be avoided to prevent
postoperative stenosis
• Instrumentation to remove disease posteriorly,
posterolaterally, or superiorly in sphenoid sinus should be
avoided to avoid injury to ICA, optic nerve, and skull base

39. 8. Completion of Ethmoidectomy and Skull Base Dissection:
• Skull base, easily visualized within and superior to opening of
the sphenoid sinus or within posterior ethmoid
• Remaining septations and cells of the posterior and anterior
ethmoids are removed in posterior-to-anterior direction

40. • The frontal recess and agger nasi area are opened last in
complete or anterior ethmoidectomy as bleeding from above
can reduce endoscopic visualization and may hamper
dissection of lower cells

41. 9. Frontal Sinusotomy:
• Not necessary in asymptomatic nasal polyposis, as polyps
routinely recur at frontal sinus and recess
• Frontal sinus drainage pathway is determined by insertion of
the uncinate process to: roof of ethmoid centrally; middle
turbinate; and lamina papyracea laterally

42. • Bent & Kuhn classification of fronto-ethmoid cells:
I. Type 1: Single cell above agger nasi not extending into
frontal sinus (25%)
II. Type 2: Group of cells (>2) above agger nasi cell but below
orbital roof (5%)
III. Type 3: Single cell that extends from agger nasi cell into
frontal sinus, above its floor floor but less than 50% of
frontal sinus height
IV. Type 4: An isolated cell within frontal sinus (Kuhn) or a
single cell that extends into frontal sinus for greater than
50% of frontal sinus height (Wormald)

43. • Excessive pneumatisation of these cells (especially Types 3
and 4) may obstruct the frontal recess

44. • Dissection is performed by first opening up agger nasi cell
and then sequentially removing subsequent frontal sinus
cells
• If uncinate attaches to middle turbinate or to fovea
ethmoidalis  Removal of most superior aspect of uncinate
provides access to frontal recess
• When uncinate attaches to lamina papyracea frontal recess is
found between middle turbinate and superior extent of
uncinate process

45. • A large agger nasi, frontal, or supraorbital cell can easily be
confused with the frontal recess

46. 10. Treatment of the Middle Turbinate:
• Vertical and posterior horizontal attachments of middle
turbinate should be preserved to prevent destabilization and
lateralization
• Lateralized middle turbinates causes  postoperative
obstruction of middle and superior meatus  block sinus
drainage persistent inflammation and infection  need for
revision surgery

47. 11. Concluding the Procedure:
• All small bone fragments are removed
• Hemostasis is achieved
• Small pack may be placed into middle meatus to keep middle
turbinate medialized
• Nasal packing is usually not necessary for hemostasis after
ESS
• Throat pack placed preoperatively removed

48. SPECIAL SITUATIONS:
1. Nasal Septal Deviation:
• Septoplasty, if it makes endoscopic procedure simpler, or
makes postoperative endoscopy and debridement easier
2. Concha Bullosa:
• Removal improves visualization of middle meatus
• Anterior wall of concha bullosa is incised to open the cell
with sickle knife
• The lateral wall is removed posteriorly to basal lamella

49. 3. Polyps:
In primary procedure, polyps are easy to approach
endoscopically as they are gelatinous and have minimal blood
supply
Revision polyp surgery is technically more difficult
Microdebrider can help reduce blood loss and improves
visualization
In extensive polyposis, polyps cleared anteriorly and
inferiorly, until middle turbinate and other landmarks
identified

50. POSTOPERATIVE CARE:
• In the recovery room, quick assessment of vision and mental
status
• Appropriate antibiotics for patients with purulent drainage
or nasal packing
• Saline nasal irrigations after pack removal
• Advised to avoid strenuous activity, nose blowing, and any
medications that may increase risk for bleeding

51. Terminologies:
• mini-FESS : simple middle meatal antrostomy and anterior
ethmoidectomy
• full-house FESS : complete fronto-spheno-ethmoidectomy
• Intact bulla technique : Frontal sinus surgery via the route
anterior to ethmoid bulla

52. Balloon Sinusotomy and Balloon-Assisted
Sinus Surgery
• Sinus balloon catheterization :
Surgical technique by which dilation of a paranasal sinus
ostium is accomplished via balloon catheter

53. • Procedure:
Ostium of appropriate sinus is located based on anatomic
landmarks
Rigid or flexible illuminated guidewire is passed into sinus
ostium
Balloon passed over it, or it may be integrated into
guidewire system
Inflation of balloon for a period of time at preferred
pressure results in dilation of targeted ostium

55. • Mild to moderate disease in maxillary, ethmoid, or sphenoid
sinuses are likely to be treated
• Its use in severe disease (e.g. nasal polyposis or AFRS) is
controversial
• Dehiscences in skull base and orbit relative contraindications
 likelihood of dural, intracranial, or orbital injury
• Two balloon systems are currently approved by United
States FDA; Acclarent and Entellus