1. The document discusses the surgical and functional anatomy of the lateral nasal wall and paranasal sinuses, including key anatomical structures and landmarks.
2. It also covers preoperative considerations for endoscopic sinus surgery, such as patient assessment, radiographic evaluation, preoperative medical therapy, and choices for anesthesia.
3. Intraoperative techniques are described, including the use of image-guided navigation systems, total intravenous anesthesia to improve surgical field visualization, and topical anesthesia administration.
2. The Lateral
Nasal Wall
the vestibule Anteriorly in the area of the nostril, the lateral nasal wall is lined by skin
and has hair
the atrium. is a plain structureless area lined by nasal mucosa
agger nasi cell as a bulge anterior to the middle turbinate
Very often a ridge can be discerned extending from the agger nasi cell to
an apex on the superior border of the inferior turbinate. This ridge overlies
the nasolacrimal duct
3. Behind the atrium are the three scrolls of the inferior,
middle and superior turbinates, overlying the
respective meatii
Above the superior turbinate is the sphenoethmoidal
recess, which gets its name from the fact that this
area forms a niche between the posterior ethmoid
cells and the sphenoid sinus
4. The posterior end of the middle turbinate ends at the
level of the roof of the posterior choana.
The eustachian tube lies in the nasopharynx at the
level of the inferior turbinate 1 cm behind its
posterior attachment. The fossa of Rosenmueller
forms a deep cleft behind the torus tubaris.
5. The base skull sloping
downwards from an
anterior to posterior
direction at an angle of 15
Anteroinferior to the
frontal sinus is the
thickened frontal beak
anterior wall of the
sphenoid is thicker
inferiorly than superiorly.
6. Middle turbinate
1. Anterior (vertical) attachment
to agger nasi and cribriform plate
3. Posterior (horizontal/axial) attachment
to maxilla, palatine bone, orbit
2. Middle (coronal/oblique) attachment
to lamina papyracea
4. Free anterior edge
7. Surgical anatomy of the
paranasal sinuses
anatomical landmarks include:
(1) the maxillary sinus
(2)the orbit from the maxillary sinus roof / orbital
floor and medial orbital wall (lamina papyracea)
(3) skull base identified posteriorly by the sphenoid
sinus
These defined anatomical limits establish the
boundaries of the paranasal surgical box
8. Upon completion of the maxillary
antrostomy (or any maxillary sinus
opening), identification of the
maxillary sinus roof/orbital floor
exhibits the first key anatomical
landmark
the maxillary sinus roof / orbital
floor below the level of the skull base
(lowest portion of the cribriform
plate) in 100% of cases with an mean
distance of 10.1 ± 2.7 mm.
This landmark was also found to be
below the level of the sphenoid
planum in 100% of cases with a mean
distance of 11.0 ± 3.7 mm and located
at approximately 50% the height of
the sphenoid
9. Line indicates the horizontal
relationship between the
maxillarysinus roof / orbital floor
landmark and position of the
sphenoidostium.
White oval indicates the relative
position of the sphenoid ostium.
Application of this landmark will
ensure safe and easy identification of
the sphenoid sinus and avoids
mistaking
a posterior ethmoid cell or Onodi cell
(asterisk) for the true sphenoid sinus.
Note that within the Onodi cell is the
presence of an exposed optic nerve
(arrow heads)
10. With the orbital floor on view,
removal of the ethmoid bulla enables
identification of second key
anatomical landmark Identification
of where the floor turns vertically to
become the medial orbital wall
enables safe exposure of the entire
orbital axis and delineation of the
lateral boundary of the paranasal
surgical box
The position of the right medial
orbital wall (asterisk) is identified
after removal of the ethmoid bulla.
The transition from the orbital floor
to the medial orbital wall is clearly
delineated (arrow).
11. The third key landmark is
the sphenoid
sinus/posterior skull base
The maxillary sinus
roof/orbital floor landmark
is used as a reference to
mark the level of the
sphenoid ostium. Any
dissection medial to the
orbital axis and below or at
the level of the orbital floor
will allow safe entry into
the sphenoid
12. the paranasal surgical box
The concept of the paranasal surgical box forms the
basic framework of endoscopic sinus surgery
It consist of horizontal and vertical components
13. Horizontal part
medial orbital wall (blue)
middle turbinate (grey)
skull base (green)
Sphenoid sinus (yellow)
Floor of the nose
14. The vertical part
nasal beak (blue
skull base (blue) and
posterior table of frontal
sinus (green)
middle turbinate (blue)
and frontal intersinus
septum (green)
medial orbital wall (blue)
and supraorbital
roof(green)
15. The boundaries of the vertical portion of the
paranasal surgical box include the middle turbinate
and intersinus septum medially, lamina papyracea
laterally, nasofrontal beak anteriorly and skull base
posteriorly
16. The osteomeatal complex
comprises the
uncinate process, ethmoid
infundibulum, hiatus
semilunaris,anterior ethmoid cells, and
the ostia of the anterior
ethmoid,maxillary, and frontal
Sinuses
The uncinate process
is a sickle-shaped bone that runs
anterosuperior to posteroinferior,
with fibrous and bony attachments
along the lateral nasal wall. It lies in the
sagittal plane and forms the medial
wall of the ethmoid infundibulum
17. The ethmoid infundibulum is a
funnel-shaped three-dimensional
space between the uncinate process
medially and the lamina papyracea
laterally, into which the anterior
sinuses drain The maxillary sinus
opens into the inferior aspect of the
ethmoid infundibulum at a 45-
degree angle, and the frontal sinus
may drain into its superior part
Hiatus semilunaris, is a two-
dimensional slit that lies between
the free edge of the uncinate
process and the ethmoid bulla. It is
a cleft that connects the middle
meatus into the infundibulum
laterally
18. The frontal sinus recess (FSR)
is an hourglass-shaped space with
the waist at the frontal sinus ostium
(FSO), which is its
narrowest part. In the simplest
configuration, the boundaries of the frontal
recess are limited by the agger nasi cell
(ANC) and nasal beak (NB) anteriorly,
The bulla ethmoidalis (BE) and the bulla
lamella (BL) posteriorly,
the anterior skull base (SB)
posterosuperiorly, the cribriform plate and
middle turbinate medially,
and the lamina papyracea laterally..
20. PREOPERATIVE ASSESSMENT
History
*prior medical therapy for CRS is critical
in determining whether the patient needs surgery
*Factors that have been associated with
poorer outcomes from surgery must be assessed
preoperatively. These include smoking, asthma, aspirin
sensitivity, allergies, immunodeficiency, and
depression
*The patient’s response to medical therapy and
previous operations
*any preexisting comorbidities influences their
candidacy for surgery
22. 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
23. Instrumentation for ESS
Includes;
array of endoscopes (0,30, 45, and 70 degree)
An appropriate set of straight and angled instruments to
approach all sinuse should be available
Powered instrumentations such as shavers
(microdebriders) are very useful in patients with polyps,
and they also help to create sharp mucosal edges
The image guidance system is optional for use where
Indicated
24.
25. Instruments v telescope
The telescope is positioned
at the nasoseptal angle
with gentle superior
retraction of the nasal tip,
and the surgical
instrumentation is inserted
inferior to the telescope
26. A 70-degree telescope can be
used if further visualization is
required into the superior or
lateral recesses of the frontal,
maxillary, or sphenoid sinus.
The 30-degree or 70-degree
telescope is placed along the
floor of the vestibule looking
superiorly (as when working
around the frontal ostium) or
medially (as when performing
a septoplasty). In these cases,
the instruments are
introduced superior to the
telescope
27. In some advanced skull
base procedures, where
drilling of bone or
manipulating tissue around
critical neurovascular
structures is necessary, it is
helpful to have the
telescope fixed in place
with the help of an
assistant, or by utilizing a
specially designed
telescope holder, allowing
the surgeon to operate with
both hands simultaneously
28. Many interventions have been proposed to optimize
hemostasis These include;
use of the reverse Trendelenburg position,
administration of topical vasoconstrictors,
use of a laryngeal mask airway, and favorable
anesthetic techniques
29. Preoperative steroid
Medium-dose prednisone (30 to 40 mg/
day) for 4 to 7 days was the most commonly used steroid
regimen,
Benefits noted
1. decreased mucosal inflammation,
2. improved surgical field visualization,
3. decreased surgical time,
4. decreased surgical bleeding
5. decreased disease recurrence rate
6. greater improvement in symptoms,
7. better postoperative results,
8. and decreased need for revision
30. PREOPERATIVE MEDICAL THERAPY
Antibiotics and oral steroids may be started 7 to 10
days before surgery to;
reduce inflammation from purulent CRS or nasal
polyposis and reactive lower airway disease to
improve the surgical field,
reduce bleeding,
and prevent respiratory complications.
31. INTRAOPERATIVE CONSIDERATIONS
Image-Guided Navigation Systems
These systems use thin-cut CT scans reformatted in various
planes to create a three-dimensional configuration. This three
dimensional view is then correlated with actual patient anatomy
intraoperatively with the help of a computer,
( The surgeon can place a probe on any structure to get a real
time three-dimensional view of the position of the probe)
Accuracy to within 2 to 3 mm is acceptable for image guidance
systems, making them most useful in confirming the identity of
large compartments (posterior ethmoid vs. sphenoid sinus)
rather than distinguishing between millimeter increments,
such as in the skull base
32. IGNS
Image-guided navigation systems use reformatted thin-cut computed tomography
scans in coronal (top left), sagittal (top right), and axial section (bottom left)
to create a three-dimensional view that is correlated intraoperatively with actual
patient anatomy as seen through the endoscope
(bottom right).
33. IGNS
Potential sources of error include
1. variables during CT scanning,
2. headset shift,
3. soft tissue effects during surface registration,
4. and operator-dependent errors during registration
5. with an associated increase in operative time and
cost
34. IGNS
The American Academy of Otolaryngology–Head and Neck
Surgery use of these systems for such things as
1) revision sinus surgery;
2) distorted sinus anatomy of developmental, postoperative, or
traumatic origin;
3) extensive sinonasal polyposis;
4) Pathology that involves the frontal, posterior ethmoid, and
sphenoid sinuses;
5) disease that abuts the skull base, orbit, optic nerve,
or ICA;
6) CSF rhinorrhea or conditions in which there is a
skull base defect; and
7) benign and malignant sinonasal neoplasms
35. Choice of Anesthesia
Local Anesthesia.
Sedation with local anesthesia calms patients, stabilizes blood
pressure, and minimizes bleeding.
In theory, local anesthesia improves safety, because awake patients
can report manipulation of the orbital periosteum or dura.
Local anesthesia works well for young patients undergoing primary
ESS for less than 2 hours.
If the patient becomes unstable during surgery, bleeding should be
quickly controlled, intravenous (IV) sedation should be
stopped, the procedure should be halted, and general anesthesia
should be administered
36. General Anesthesia.
General anesthesia offers independence from patient
cooperation and patient control of the airway.
It is useful for anxious patients and children, and it is
good for long procedures.
General anesthesia is also indicated if computer-
assisted navigation systems are used, because any
patient movement may disrupt the reference device
37. improvement in surgical field during ESS
when patients received TIVA compared with
inhalational anesthesia.
Laryngeal mask airways have also been substituted
for endotracheal intubation to ;
decrease the hemodynamic response to endotracheal
intubation,
minimize positive end expiratory pressure,
and improve venous return
38. TIVA has been proposed as a preferred anesthetic in
ESS, because it is thought that ;
TIVA decreases cardiac output without the
significant decrease in systemic vascular resistance
often seen with volatile agents
Improved hemostasis and visualization during FESS
may likely be best achieved with a combination of
preoperative oral steroids , TIVA, and
intraoperative topical vasoconstrictors.
39. The use of volatile inhalation agents has declined
Due to the availability of short acting opiates such as
Remifentanil, so many surgeons prefer total
intravenous anaesthesia (TIVA).
With TIVA there is a very small but real risk of
awake anaesthesia and therefore the use of
bispectoral index (BIS) monitoring is recommended
to avoid this potentially serious medicolegal
complication
40. the use of sevoflurane (at low concentration only)
and remifentanil combined probably provides just as
good a surgical field and avoids the need for BIS
monitoring.
In order to optimize the surgical field, hypotensive
anaesthesia is desirable. to maintain a systolic MAP
of approximately 90 mmHg, which is best achieved
by maintaining the HR at approximately 60 beats
per minute.
Mean arterial blood pressure (MAP) is determined by the
following equation: MAP = heart rate (HR) x stroke volume (SV)
x systemic vascular resistance (SVR).
42. Volatile agents, which achieve hypotension by
reducing SVR, can paradoxically cause a
deterioration of the surgical field due to
vasodilatation of the nasal microvasculature
43. Topical Anesthesia.
A solution of lidocaine 1% with epinephrine
1 : 100,000 may be injected using a nasal speculum and
headlamp prior to draping the patient
A transoral greater palatine block is helpful in decreasing
bleeding.
the cerebral perfusion pressure remains constant at
elevations of between 0 and 30
elevation has been demonstrated to produce a 38.3%
reduction in nasal blood flow, injection of the greater
palatine canal only produces a
reduction of 4.7%
44. Topical decongestion in the form of[ cocaine(2ml 10%)
and adrenaline(1ml 1/1000), +/− sodium
bicarbonate(2ml 2%)-- (‘Moffat’s solution’) ]soaked on
neuro-patties, ribbon gauze or pledgets remains most
commonly used
Toxic reactions from overdose have been reported and the use
of adrenaline will frequently cause a rise in heart rate with a
corresponding temporary deterioration in the operative field
(which may be greater than the gained benefit of the
vasoconstrictor effect). Rather than immediately proceeding to
surgery, it is therefore preferable to allow a period of time for
topical and injected vasoconstrictors to establish their local
effect, whilst allowing their systemic effect to dissipate
45. The anterior ends of the
nasal septum, inferior
turbinate, and middle
turbinate are injected
Injection of the nasal
dorsum and infraorbital
and greater palatine
blocks may be used when
local anesthesia is being
used
SITES FOR INJECTION
46. After injection, cotton pledgets soaked in cocaine,
tetracaineephedrine, or concentrated epinephrine
solution are placed into the nasal cavity for
additional topical anesthesia and vasoconstriction.
Alternately, pledgets may be placed prior to draping,
and injections are placed under direct endoscopic
visualization after draping
47. Higgins and colleagues conducted a systematic review of
topical vasoconstrictors in ESS in regard to efficacy and
safety
1) avoid use of topical phenylephrine if possible because
of risk of serious cardiac complications;
2) use caution with topical cocaine;
3) avoid β-blockers for intraoperative hypertension after
topical vasoconstrictor use;
4) avoid halogenated hydrocarbon anesthetic agents
when using topical vasoconstrictors; and
5) avoid using concentrated topical cocaine or
epinephrine in patients with a history of cardiovascular
disease
48. Their dosage recommendations
for neonates to 85 pounds, or a 12-year-old child,
were to consider using 0.05% oxymetalozine first. If
adequate visualization or hemostasis is not achieved,
consider 1 : 2000 topical epinephrine with judicious
use.
For patients from 85 pounds or 12 to 17 years of age,
the use oxymetalozine or 1 : 2000 epinephrine
judiciously is recommended.
For those 18 years or older, use 1 : 2000 or 1 : 1000
epinephrine judiciously
49. Boezaart and van der Merwe Grading System for
Bleeding During Endoscopic Sinus Surgery
Grade (1 )Cadaveric conditions with minimal suction
required
Grade( 2) Minimal bleeding with infrequent suction
required
Grade (3) Brisk bleeding with frequent suction
required
Grade (4) Bleeding covers surgical field after removal
of suction before surgical instrument can perform
maneuver
Grade (5 )Uncontrolled bleeding; bleeding out of
nostril on removal of suction
50. The Wormald Grading System for Bleeding
During Endoscopic Sinus Surgery*
0 No bleeding
1 1–2 points of ooze (no blood in the sphenoid)
2 3–4 points of ooze (no blood in the sphenoid)
3 5–6 points of ooze (slight blood accumulation in the sphenoid)
4 7–8 points of ooze (moderate blood accumulation of sphenoid; fills after
90 seconds)
5 9–10 points of ooze (sphenoid fills after 60 seconds)
6 More than 10 points of ooze, obscuring surface (sphenoid fills between 40
and 60 seconds)
7 Mild bleeding/oozing from entire surgical surface with slow accumulation
of blood in postnasal space (sphenoid fills by 40 seconds)
8 Moderate bleeding from entire surgical surface with moderate accumulation
of blood in postnasal space (sphenoid fills by 30 seconds)
9 Moderately severe bleeding with rapid accumulation of blood in postnasal
space (sphenoid fills by 20 seconds)
10 Severe bleeding with nasal cavity filling rapidly (sphenoid fills in , 10
seconds)
52. steps
i) Uncinectomy
ii) Removal of the ethmoidal bulla
iii) Posterior ethmoidectomy
iv) Sphenoidotomy
v) Frontal sinus surgery
53. 1. Nasal Endoscopy
Landmarks, structural abnormalities, the condition of
the mucosa, presence of any polyps or pus, and any
significant differences from the preoperative
examination are noted.
At this time, additional injections of 1 mL of lidocaine
with epinephrine 1 : 100,000 may be injected into the
lateral nasal wall above the axilla and middle turbinate
If a significant septal deviation is present, the wider side
should be approached first if possible, because there is
more space to work there prior to correcting the nasal
septum
54. 2. Middle Turbinate Medialization.
gently with a Freer elevator creates better
visualization of the middle meatus
Aggressive manipulation of the middle turbinate
should be avoided, because it can lead to
destabilization of the turbinate and fracture at the
skull Base
A formal relaxing incision into the middle turbinate
basal lamella has recently been described, which
avoids uncontrolled destabilization and increases
operative space in the middle meatal space
55. Middle turbinate (MT) medialization.
A, Native position of the middle
turbinate in the left nasal cavity.
B, The middle turbinate is gently
medialized with the help of a Freer
elevator.
C, Optionally, a formal basal lamella
relaxing incision is made through all
three layers of the middle turbinate
basal lamella at the junction of the
oblique and vertical parts just medial to
the bulla ethmoidalis (BE) through all
three layers. Horizontal attachment is
carefully preserved to prevent
destabilization and bleeding.
D, After medialization, more space is
is created in the middle meatus.
56. 3. Resection of the Uncinate Process.
A- retrograde Uncinectomy
Anteriorly, the border is seen as a sharp line at the
junction with the frontal process of the maxilla (the
anterior maxillary line)
When polyps are present, the uncinate is best
identified from its posterior free end, which often has
a rolled out or everted edge
57. To initiate the uncinectomy, a ball-tipped probe is slid into the
infundibulum behind this posterior free edge to medialize the
uncinate process into the middle meatus, off the lamina
papyracea
A pediatric backbiter punch is used to retrogradely incise the
uncinate process via the hiatus semilunaris in an axial plane
between the inferior one third and superior two thirds of the
uncinate process.
The incision is continued anteriorly until the harder lacrimal
bone is encountered, endoscopically seen as the anterior
maxillary line
58. Once this uncinate incision is complete,
the middle third of the uncinate is removed with suitable
cutting instruments.
The superior third may be preserved at this time to
prevent frontal recess scarring or to assist with frontal
recess dissection later
The inferior aspect is rotated medially with a Lusk probe
and is removed with the combination of a downbiting
instrument and a microdebrider
Any rough edges can be removed using a 2 mm
Kerrison’s punch
59.
60. B-anterograde
uncinectomy
Performed with a sickle
knife, or an elevator can be
used to resect the uncinate
process via a vertical
incision that starts on its
anterior aspect and is
continued inferiorly and
posteriorly along the
crescent-shaped anterior
margin.
61. 4. Maxillary Antrostomy
The maxillary sinus ostium is elliptical and is usually
found in the floor of the infundibulum lateral to the
lower third of the uncinate
Because the ostium opens at a 45-degree angle in the
floor of the infundibulum, it is best visualized and
manipulated with the help of an angled 30- or 45-
degree endoscope
Accessory ostia are more circular and are commonly
found within the posterior fontanelle
The natural ostium of the maxillary sinus cannot be
visualized without removal of the uncinate process.
62. A Lusk probe can be gently passed into the
infundibulum to help identify the natural ostium.
To avoid penetration of the orbit, the probe is never
forced through the bony wall.
If the natural ostium is patent, it should not be
manipulated.
If it is edematous and obstructed, the Lusk probe can
then be used to open it further both posteriorly and
inferiorly if necessary.
A straight punch can be used to dilate it posteriorly.
63. A backbiter punch can also be used to open the
anterior aspect of the ostium, with care taken to
remove only residual uncinate process.
Biting anteriorly in the natural ostium is usually
unnecessary and may damage the nasolacrimal duct.
It is important not to strip mucosa off, so as to
prevent scarring and mucociliary dysfunction
Once the maxillary antrostomy is complete, the sinus
is carefully examined with angled 30-, 45-, or 70-
degree endoscopes
64. Landmarks, including the medial and inferior orbital
wall, are carefully identified.
Occasionally, an infraorbital cell may block the
antrostomy from above; this cell can now be safely
opened.
65. 5. Anterior Ethmoidectomy.
A-Retrograde
If there is a retrobullar space, this can be entered
into, and the ethmoid bulla can be removed in
retrograde fashion
B-Antegrade
If no retrobullar space exists, a curette,
microdebrider, or a punch forceps can be used to
enter the ethmoid bulla along its inferior and medial
aspect
66. The natural ostium of the ethmoidal bulla sits
posteromedial to the anterior face. The ostium
can be located by several methods; a double
right angled ball probe or 45 ° antral curette can
then be used to fracture the anterior face
forwards A microdebrider can then be used to
remove the bulla
When removing the bulla superiorly, it is
important to recognize the location of the
anterior ethmoidal artery
The use of through-biting instruments is
preferred to standard Blakesley-Wells forceps
as the latter can tear mucosa and leave exposed
bone in the final sinus cavity
Removal of the ethmoidal bulla
67. The anterior and medial walls are removed to expose the
posterior Wall
Some surgeons leave the inferior wall intact as a strut to keep
the turbinate medial
Mucosa should be preserved on the lamina papyracea
Opening the agger nasi and suprabullar cells completes the
anterior ethmoidectomy,
but the opening is performed only after the skull base
is identified
Dissection should never be carried out medial to the
superior vertical attachment of the middle turbinate, because
such extension carries the risk of penetrating the cribriform
plate and fovea ethmoidalis
68. Dissection should continue posteriorly, until the
basal lamella is identified, which is the posterior
limit of the anterior ethmoid.
The microdebrider window should always face up
when working along the lamina papyracea to prevent
inadvertent orbital injury
69.
70. 6. Posterior Ethmoidectomy
once the superior turbinate and the superior meatus have been identified,
posterior ethmoid cells can be removed from the medial aspect toward the
lamina papyracea, staying low until the skull base is identified
To open the posterior ethmoids, the inferior and medial aspects of the
vertical basal lamella must be removed with the microdebrider or curette
If a relaxing incision has been performed in the basal lamella previously to
medialize the turbinate, this incision can also be used to initiate posterior
ethmoidectomy.
Otherwise, the inferomedial part of the vertical middle turbinate basal
lamella is carefully removed with a curette, punch, or microdebrider
Once the posterior ethmoid is opened, the roof of the maxillary sinus can be
used as a guide to the superior limit of dissection within the posterior
ethmoid
The boundaries of the posterior ethmoidectomy are between the lamina
papyracea laterally and the superior turbinate medially.
71. Care is taken not to open the horizontal basal lamella,
because to do so not only destabilizes the middle
turbinate, it also exposes the vessels coming from the
sphenopalatine artery, causing immediate or delayed
hemorrhage
A calibrated probe or computerized navigation system is
useful at this point to identify the anterior wall of the
sphenoid sinus.
In an average adult, this structure is approximately 7 cm
from the nasal sill at a 30-degree angle
The skull base can then be identified anterior and
superior to the sphenoid face
72. The last posterior ethmoid cell lies superolateral to the
sphenoid sinus.
Sometimes, a large posterior ethmoid cell may be
mistaken for the sphenoid sinus. If the floor of this cell
can be visualized by a zero-degree endoscope, this is
usually a posterior ethmoid cell and not the sphenoid
sinus
. Also, the natural sphenoid ostium is almost always
medial to the superior turbinate Attachment
A microdebrider, Kerrison’s punch or through-biting
instruments can be used to remove the partitions
between the posterior ethmoid cells
73.
74. 7. Sphenoid Sinusotomy.
The anterior wall of the sphenoid sinus is usually
convex, toward the surgeon, whereas the skull base is
concave, away from the surgeon
The ostium of the sphenoid sinus can be approached
transethmoidally, lateral to the middle turbinate.
This may be done by either entering the sphenoid in the
inferomedial part of the most posterior ethmoid, or more
physiologically, through the sphenoethmoidal recess after
exposing the superior turbinate and superior meatus through
the middle turbinate basal lamella removal
The inferior third to half of the superior turbinate may have
to be removed for full visualization of the sphenoethmoidal
recess and the sphenoid ostium in the anterior wall of the
sphenoid sinus
75. The ostium can also be identified transnasally,
medial to the middle turbinate, through the nasal
cavity if there is no septal obstruction
In either approach, the lower third to half of the
superior turbinate is removed with cutting forceps,
and in most cases, this maneuver exposes the ostium
just medially or directly posteriorly
76. The ostium is located approximately half the
distance between the superior and inferior borders of
the anterior wall
The natural ostium can be located by gentle sliding
of a probe along the anterior wall until it easily
passes
(Theprobe should never be forced, so as to avoid
injury to the skull base, optic nerve, and ICA)
77. The surgeon widens the ostium by inserting a small
curette or straight forceps, with the opening directed
first medially and inferiorly
A sphenoid punch or microdebrider can then be used
to safely widen the ostium as needed.
A circumferential opening should be avoided to
prevent postoperative stenosis
78. surgeon should be aware that small arterial branches
from the sphenopalatine artery may be present
medially or laterally that could cause bleeding
Instrumentation to remove disease posteriorly,
posterolaterally, or superiorly in the sphenoid sinus
should be avoided unless guided by a well-calibrated
computer navigation system to avoid injury to the
ICA, optic nerve, and skull base
79. Septations should not be unnecessarily removed,
because they may attach posteriorly to a dehiscent or
weak carotid wall.
80.
81. 8. Completion of Ethmoidectomy and Skull Base
Dissection
Once the orbit and skull base have been identified,
posterior-to-anterior dissection of the superior ethmoids
can proceed
The tip of the instrument should always be behind a
partition before its removal; otherwise, the surgeon
might be biting on the skull base
This dissection can be conducted by 45-degree cutting
forceps or blunt instruments such as a curette or curved
suction tube.
The dissector is never thrust upward if it appears flush
with a structure;
only tangential dissections are performed
82. The frontal recess and agger nasi area are opened
last in a complete or anterior ethmoidectomy,
because bleeding reduce endoscopic visualization
and may hamper dissection of lower cellsfrom above.
The superior aspect of the agger nasi may lie close to
the skull base, and the lateral or anterior aspect may
be contiguous with the lacrimal sac and orbit. It is
safely opened from the inferior, medial, or posterior
to anterior aspect after the skull base has been
identified
83. Completing left-sided ethmoidectomy with skull
base (SB) dissection.
A, The SB is identified in the sphenoid sinus
(SS) and posterior ethmoid (PE).
B, Remaining septations and cells of the
posterior and anterior ethmoids are removed
in a posterior-to-anterior direction, with the
tip of the instrument always kept behind a
partition before removing it.
C, The SB is opened in the suprabullar area.
D and E, Frontal sinusotomy (FSO) is
performed next to identify the SB in the
posterior frontal table.
F, The ethmoid partitions are then removed
in the posterior frontal recess area to create
a smooth transition from the posterior
frontal table to the anterior ethmoid SB .
84. 9. Frontal Sinusotomy.
The Agger nasi cell is key to all approaches to
the frontal Recess
Computerized image guidance can be very helpful in
conducting frontal sinus dissection, especially in a
complex pneumatization pattern
Although dissection can be initiated with a zero-
degree endoscope, 30-, 45-, and 70-degree
endoscopes may be necessary for dissection higher
up in the recess, depending on the pneumatization
pattern.
85. When the uncinate attaches to the lamina papyracea,
as it usually does, the frontal recess is found between
the middle turbinate and the superior extent of the
uncinate process.
Once the frontal recess anatomy has been defined, a
curved frontal probe may be passed into the sinus.
Frontal “giraffe” instruments and curved curettes are
utilized to perform meticulous, mucosalpreserving
dissection to remove cellular partitions around the
recess to widen it.
86. Using a Kerrison’s
punch in the axilla of
the middle turbinate
the anterior portion of
the Agger nasi can be
removed
87. Curettes and angled instruments
can then be used to remove the
posterior wall and roof of the Agger
nasi to expose the frontal recess
Once the Agger nasi has been
removed, any remaining fronto-
ethmoidal cells can be removed
using through-biting instruments,
curettes or angled microdebrider
blades
When dissecting the frontal recess,
the position of the anterior
ethmoidal artery needs to be
identified and maintained in the
surgeon’s mind at all times
88. Advanced frontal
instrumentation such as
a giraffe forceps or 3.5
mm Hosemann punch
may greatly facilitate
surgery in this area
Use of a Hosemann
punch to facilitate
removal of Kuhn cells in
the frontal recess
90. POSTOPERATIVE CARE FOR ENDOSCOPIC
SINUS SURGERY
Once a patient has emerged from sedation or general
anesthesia, the head should be elevated
In the recovery room, a quick assessment of vision
and mental status is performed
Saline nasal spray and a short course of a nasal
decongestant are prescribed, and saline nasal
irrigations may be initiated the day after surgery, if
no nasal packing is utilized
91. For patients with purulent drainage or nasal packing,
appropriate antibiotics are dispensed
Patients with reactive airways, fungal disease, or
extensive polyps often benefit from steroid “burst”
therapy to reduce postoperative mucosal edema
Patients are advised to avoid strenuous activity, nose
blowing, and any medications that may increase the
risk for bleeding
92. Loose crusts and clots are removed, because this
helps promote mucosal healing.
Fixed clots or crusts should not be removed; this is
important, because such removal can damage the
mucosa, cause bleeding and scar, and slow healing
93. COMPLICATIONS OF ENDOSCOPIC SINUS
SURGERY
Minor Complications
1. Minor epistaxis
2. Hyposmia
3. Adhesions
4. Headache
5. Periorbital ecchymosis or emphysema
6. Dental or facial pain
Major Complications
1. Major epistaxis
2. Anosmia
3. Nasolacrimal trauma
4. Carotid injury, intracranial hemorrhage, stroke
5. Orbital hematoma, diplopia, decreased visual acuity, blindness
6. Cerebrospinal fluid leak, pneumocephalus, meningitis
94. Ophthalmic Complications
The eyes should always be included in the surgical
field, so they can be easily examined during surgery.
Simultaneous endoscopic viewing of the lateral wall
with orbital palpation will show the slightest breech
in the lamina papyracea and is a useful preventive
tool.
With any orbital complication, an immediate
ophthalmologic consultation should be obtained, and
intraorbital pressures should be measured
95. arterial or venous in origin
Bleeds from the anterior or
posterior ethmoid arteries
may lead to rapidly expanding
hematomas, which in turn
cause a sudden increase in
intraorbital pressures and
must be treated Aggressively
Simultaneous efforts are
made to relieve the elevated
intraorbital pressure and stop
the bleeding
Orbital Hematoma
96. A lateral canthotomy and cantholysis may be
necessary to relieve intraorbital pressure.
If the artery has retracted into the orbit, an
endoscopic orbital decompression with cautery or
clipping is helpful.
If this maneuver is not possible, an external
ethmoidectomy can be performed to isolate the
vessel and decompress the orbit.
Other therapies include orbital massage and the
administration of osmotic agents
97. Venous bleeding, such as that from the veins that
line the lamina papyracea, leads to slowly
progressive orbital hematomas.
These lesions may not be recognized until the patient
is in the recovery room or at home.
Treatment should be similar to that for arterial
orbital hematomas.
98. Blindness
Elevated intraorbital pressure causes blindness after 60
to 90 minutes or even sooner with rapid arterial
hemorrhage
Blindness can also result from injury to the optic nerve in
the orbit, in the sphenoid sinus, or within a
sphenoethmoid cell.
An ophthalmologic consultation is obtained
immediately.
In addition, any nasal packing is removed.
Orbital decompression, which may include
decompression of the optic nerve, may be needed;
steroid administration may also be beneficial.
99. Diplopia
damage to the ocular musculature, most commonly
the medial rectus and the superior oblique Muscles
Diplopia can be caused by breaching of the lamina
papyracea and entry of the orbit or by pulling of
orbital contents through a dehiscence into the
ethmoid sinus with a microdebrider;
thus it is important to always to keep this instrument
tangential to the lamina papyracea.
Diplopia caused by injury to the muscle must be
treated by an ophthalmologist and generally has a
poor prognosis
100. Nasolacrimal appertus inj.
The nasolacrimal sac and duct are in close relation to the natural
ostium of the maxillary sinus as well as to the anterior ethmoids.
To avoid injury, dissection should never be performed anterior to
the anterior margin of the middle turbinate.
The inferior antrostomy should be at least 1 cm posterior to the
anterior margin of the middle turbinate so as to avoid the
nasolacrimal duct.
Inferior or middle antrostomies should not be opened anteriorly.
Occult damage to the nasolacrimal duct was probably a common
event when antrostomies were opened anteriorly as first described
When patients are symptomatic,
a dacryocystorhinostomy may be necessary; this can be performed
endoscopically
101. Subcutaneous emphysema
Subcutaneous emphysema can result from
a small fractureof the lamina papyracea.
If the patient is subjected to large amounts of
positive pressure after extubation,
or if the patient coughs, vomits, or blows the nose,
air can become trapped in the subcutaneous and
orbital tissues.
The eyes should be examined for any other
complications. No treatment is usually necessary,
and the emphysema typically resolves in 7 to 10 days
102. Intracranial Complications
The bone of the lateral skull base is usually quite
hard, in contrast to the medial skull base, where it
can be thin, particularly in the area posterior to the
anterior ethmoid artery.
Often the fovea ethmoidalis and cribriform plate lie
lower than usual, and any dissection that occurs
superiorly along the medial aspect of the middle
turbinate risks penetration of the skull base
103. A variety of patches such as nasal mucosa, temporalis fascia,
fat, muscle, and acellular dermal grafts can be used alone or
in combination to help seal the leak.
Overlay and underlay grafting techniques work equally well,
and fibrin glue is useful in sealing and healing.
If there is a large skull base defect, bone or cartilage is used
to bridge the gap and prevent encephalocele formation.
Penetration of the skull base can lead to brain injury and to
major hemorrhage from vascular injury. These
complications are rare and require immediate neurosurgical
intervention.
104. Because of nasal packing, CSF leaks may not be apparent
during surgery or immediately postoperatively. Delayed
leaks are challenging, because it is difficult to ascertain the
site of leak.
If endoscopic examination fails to identify the source, a CT
cisternogram or intrathecal injection of fluorescein (off-
label use) with endoscopy may be helpful.
Small CSF leaks often close spontaneously, but surgery
should be considered for any leak that lasts longer than 2 to
3 weeks
105. FAILURE OF PRIMARY
ENDOSCOPIC SINUS SURGERY
The most common technical causes of surgical failure are
lateralization of the middle turbinates and
failure to incorporate the natural ostium into the middle
meatal antrostomy, resulting in recirculation,
maxillary ostium stenosis,
residual air cells and adhesions in the ethmoid area,
and frontal recess scarring.
Poor selection of candidates based on symptoms such as
facial pain may also lead to failure of relief of such
symptoms if they are due to neurologic issues.
The rate of revision surgery has been reported at 10%
with a 78% success rate.
