Endoscopic Sinus Surgery Flashcards

1
Q

Discuss the Lund-MacKay score for Chronic Rhinosinusitis

A

Radiographic staging score for CRS
- Scored out of 24
- Individual sinuses on each side (left and right) are graded
- 0 = non-opacified, 1 = partially opacified, 2 = obstructed
- Ostiomeatal complex is scored 0 or 2 (non-obstructed vs. obstructed)
- Results in a total score of 12 per side, and 24 overall
- ≤2 excellent NPV, ≥5 excellent PPV

Components:
1. Anterior ethmoids (0/1/2)
2. Posterior ethmoids (0/1/2)
3. Frontal sinuses (0/1/2)
4. Sphenoid sinuses (0/1/2)
5. Maxillary sinuses (0/1/2)
6. OMC (0/2)

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2
Q

What are the EPOS2020 criteria for endoscopic sinus surgery?

A
  1. LM score of >1 after a minimum of 8 weeks trial of appropriate medical therapy (INCS ± systemic antibiotic)

AND

  1. SNOT-22 ≥ 20 post medical treatment
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3
Q

What are the relative contraindications to endoscopic sinus surgery? 5

A
  1. Absence of OMC abnormality, LM < 2
  2. Osteomyelitis
  3. Inaccessible frontal disease
  4. Stenosed frontal ostia
  5. Threatened intracranial complication

“OSTIA”
Osteomyelitis
Stenosed frontal ostia
Inaccessible frontal disease
Threatened intracranial complication
Absence of OMC abnormality, LM < 2

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4
Q

What are the goals that are aimed to be achieved for “functional” sinus surgery?

A
  1. Creates a sinus cavity that incorporates the natural ostium
  2. Allows adequate sinus ventilation
  3. Facilitates mucociliary clearance
  4. Facilitates instillation of topical therapies

“MINi Van”
Mucociliary clearance
Instillation of topical therapies
Natural ostium
Ventilation

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5
Q

What is the spectrum of functional endoscopic sinus surgery, according to EPOS 2020? 2

A
  1. Full FESS: Complete sinus opening including anterior and posterior ethmoidectomy, middle meatal antrostomies (likely large), sphenoidotomy and frontal opening
  2. Radical FESS: Significant removal of inflamed/dysfunctional mucosa
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6
Q

How do you optimize the operative field in endoscopic sinus surgery? 5

A
  1. Positioning - Reverse trendelenburg
  2. Local anesthetic & vasoconstriction
  3. TIVA - Total IV anesthetic
  4. Tranexemic acid
  5. Hypotensive anesthesia (MAP ~ 65)
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7
Q

What are the different anatomic findings that can be found in a revision FESS (causes of failed FESS)?

A
  1. Incomplete anterior ethmoidectomy with mucosal disease - 65%
  2. Retained agger nasi with frontal disease - 50%
  3. Retained uncinate, accessory ostium - 50%
  4. Incomplete posterior ethmoidectomy with mucosal disease - 40%
  5. Middle meatal stenosis - 40%
  6. Recurrent polyps - 40%
  7. Conchal bullosa

“AEIOU Plus Me”
Agger nasi
Ethmoidectomy incomplete (anterior and posterior)
Incomplete middle turbinate - concha bullosa
Ostium accessory
Uncinate retained
Polyps recurrent
Middle meatal stenosis (synechiae)

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8
Q

Where is the targeted location of drilling for caldwell luc procedure?

What are 8 indications and 10 complications of a Caldwell Luc Procedure?

A

CALDWELL LUC:
- Through canine fossa between root of canine and 1st premolar

Indications:
1. Access for sinonasal tumors of the maxillary sinus
2. Access for the pterygopalatine fossa (e.g. IMAX ligation, vidian neurectomy, biopsy of skull base lesions)
3. Access to the orbital floor
4. Maxillary abscess drainage or foreign body, tumor, mycetoma, multiseptate mucocele, or antrochoanal polyp
5. Chronic maxillary sinusitis not amendable to endoscopic drainage
6. Repair of oroantral fistula
7. Repair of trauma
8. Orbital decompression of Grave’s ophthalmopathy

Complications:
1. Infection
2. Scarring (upper gingivobuccal sulcus)
3. Tethering
4. V2 hypoaesthesia
5. Cheek bruising/swelling
6. Damage to canine tooth root
7. Oroantral fistula
8. Facial pain or numbness of infraorbital nerve distrbution and the branches (anterior superior alveolar nerve)
9. Epiphora
10. Bone thickening

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9
Q

Regarding medial maxillectomy, discuss:
1. What are the structures taken? (5)
2. What are the indications? 1
3. What are the contraindications? 5
4. What are the complications? 9

A

STRUCTURES TAKEN: “IM LALAlA”
1. Lateral nasal wall.medial maxillary sinus wall (inferior and middle turbinate)
2. Anterior ethmoid sinuses
3. Lamina papyracea
4. Inferior and medial orbital floor
5. Lacrimal bone

INDICATIONS:
1. Benign or low-grade malignant tumors confined to medial maxillary wall and/or antrum and/or ethmoid sinus

CONTRAINDICATIONS:
Extension beyond the limits defined above, such as:
1. Involvement of the palate
2. Involvement of the periorbita/orbit
3. Skull base or intracranial extension
4. Extension to the pterygoid plates
5. Extension to the other walls of the maxillary sinus

COMPLICATIONS:
1. Telecanthus (increased distance between corners of eyelids)
2. Enopthalmos
3. Hypertrophic/keloid scar
4. Epiphora (excess tears or watery eyes) or Dacryocystitis
5. V2 paresthesias or numbness / Facial neuralgia/dysesthesia
6. Mucocele
7. Diplopia (possibly transient) / EOM muscle entrapment
8. Oroantral fistula
9. Nasal collapse

Kevan Page 45

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10
Q

Describe 5 methods to find the sphenoid os in FESS.
What are the anatomic relationships of the sphenoid ostium to the remainder of the nasal cavity?

A
  1. From Sphenoethmoidal Recess
    - Start in the sphenoethmoidal recess and take down the superior turbinate from an inferomedial to superolateral direction
  2. Below Maxillary Sinus Roof
    - Always lower than the level of the maxillary roof
  3. Angle from nasal spine
    - 6.2-8cm from the nasal spine (7cm), at an angle of 30-34 degrees (30deg)
  4. 1/2 to 2/3 up anterior wall of sphenoid
  5. Bolger’s Parallelogram

RECALL: Anatomic relationships of the sphenoid ostium
1. 7cm from the anterior nasal spine (posterior sphenoid wall ~9cm)
2. 30 degree angle from the floor of the nose (most reliable)
3. 1-1.5cm above the upper limit of the choana
4. 1/3 up from the choana to the skull base
5. Adjacent to the posterior border of the nasal septum (2-3mm)
6. Inferomedial to the posterior attachment of the superior turbinate on sphenoid face (Parson’s ridge)

Kevan Page 50

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11
Q

What is Bolger’s Parallelogram? What are its borders? What is the clinical significance?

A

Parallelogram formed by:
1. Skull base
2. Superior turbinate
3. Basal lamella of superior turbinate
4. Lamina papyracea

  • The sphenoid sinus ostium should be in the inferomedial part of the parallelogram
  • Area is safety is medial part of the parallelogram (see Kevan Page 51)

Kevan Page 51
Vancouver Pg 409

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12
Q

What are the boundaries of the opticocarotid recess?

A

SUPERIOR: Optic nerve
INFERIOR: Internal carotid artery (parasellar)
ANTERIOR: CNIII (Oculomotor nerve)

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13
Q

What are the pneumatization patterns of the sphenoid sinus?

A

4 pneumatization patterns:
1. Conchal (5%): Does not abut sella
2. Pre-sellar (15%): In front of sella
3. Sellar (80%): In front of and below sella
4. Post-sellar: In front of, below, and behind sella

Kevan Page 52

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14
Q

What are the distances of the anterior ethmoid artery, posterior ethmoid artery, and optic nerve from the lacrimal crest?

A

24-12-6 rule
- Anterior ethmoid artery is 24mm back from lacrimal crest
- Posterior ethmoid artery is 12mm back from AEA
- Optic nerve is 6mm back from PEA

Hence, distances are:
- AEA = 24mm
- PEA = 24+12mm = 36mm
- ON = 24+12+6 = 42mm

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15
Q

Describe the Draf Classification of Frontal Sinusotomy.
What is the indication for Draf I vs Draf III?

A

Draf 1: Anterior ethmoidectomy + Confirmation of FSDP
- Remove obstructing disease inferior to frontal ostium without altering ostium (e.g. anterosuperior ethmoid cells)
- Indicated in minor pathology, patient without adverse prognostic risk factors (ASA, intolerance, asthma, NP, etc.)

Draf 2a: Remove floor of frontal sinus between middle turbinate and lamina papyracea (create an opening)
- Extended drainage with ethmoidectomy and resection of the floor of the frontal sinus between the lamina papyracea and the middle turbinate

Draf 2b: Remove floor of frontal sinus between septum and lamina papyracea
- Anterior to the ventral margin of the olfactory fossa

Draf 3 (aka. Modified Lothrop): Bilateral type 2b + removal of superior nasal septum and intersinus septem of the frontal sinus to create a common cavity
- Results in an opening from Lamina Papyracea to contralateral Lamina
- Diameter should be ~1.5cm
- AP diameter of the frontal sinus should be ≥8mm to undergo a Draf III, otherwise consider an osteoplastic flap
- Indicated if chronic failure despite the above

Kevan page 54

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16
Q

What is the international classification of the extent of endoscopic frontal sinus surgery in FESS?

A
  1. Grade 0: Balloon sinus dilatation
    - No tissue removal
  2. Grade 1: Clearance of cells in the frontal recess (that do not directly obstruct the ostium) without surgery within the frontal ostium
    - SACs and SBCs that do not encroach on or obstruct the frontal ostium
  3. Grade 2: Clearance of cells directly obstructing the ostium
    - SACs or SBCs that encroach on and obstruct the FSDP
    - These cells occupy the space directly below the ostium and narrow the drainage pathway
    - Do not include SAFCs, SBFCs, or FSCs
  4. Grade 3: Clearance of cell pneumatizing through the frontal ostium into the frontal sinus without enlargement of the frontal ostium
    - SAFCs, SBFCs, and FSCs
    - Bone from the beak
  5. Grade 4: Clearance of a cell pneumatizing through the frontal ostium into the frontal sinus with enlargement of the frontal ostium
    - Large SAFCs, large SBFCs, or FSCs with a narrow frontal ostium (narrow AP diameter)
  6. Grade 5: Enlargement of the frontal ostium from the lamina papyracea to the nasal septum (unilateral frontal drill out)
    - Large SAFCs, large SBFCs, or FSCs with a narrow frontal ostium (narrow AP diameter)
  7. Grade 6: Frontal drill out/modified lothrop or Draf 3
    - Performed after failure of previous standard sinus surgery where the frontal ostium is stenosed with scar tissue or new bone formation
    - Maximum possible AP and lateral diameter
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17
Q

What are the 3 primary goals of FESS?

A
  1. Restore normal mucociliary clearance and flow
  2. Remove diseased/obstructing tissue
  3. Leave healthy tissue and sinuses alone
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18
Q

Describe your pre-op CT assessment in preparation for FESS

A

“Fucking CLOSED Man Pffft”

F: Frontal sinus/recess and agger nasi
C: Cribriform plate (Keros Classification)
L: Lamina papyracea (and uncinate relationship)
O: Onodi cells
S: Sphenoid sinus (optic nerve, ICA)

E: Ethmoid (Anterior ethmoid artery)
- Kennedy’s nipple sign
- Location of AEA: is there a supraorbital cell? Is it at risk of injury?
- Is there a mesentery or in bone?

D: Disease
- Lund-MacKay stage

M: Maxillary sinuses (Haller cells)
P: Vertical height of the posterior ethmoid

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19
Q

What percentage of anterior ethmoid arteries are hanging (mesentery) and in bone?

A

Hanging: 40%
In bone (attached to skull base): 60%

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20
Q

Describe the Keros classification of the depth of the olfactory fossa

A

Keros classification: measures the height of the vertical lamella of the cribriform plate to the fovea ethmoidalis

Type 1: Depth 1-3mm
Type 2: Depth 4-7mm
Type 3: Depth 8-16mm (greatest risk of intraoperative CSF leak, AEA injury if hanging, orbital injury, or iatrogenic frontal sinus obstruction)
Type 4: Asymmetric

Kevan page 54

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21
Q

What are 11 predictors of poor outcome or recurrence after FESS?

A
  1. Smoking
  2. AERD (Samter’s triad)
  3. Cystic fibrosis/primary ciliary dyskinesia
  4. Poor treatment compliance
  5. Significant nasal polyposis / extensive disease on pre-op CT
  6. Atopy (asthma, atopic dermatitis)
  7. Immunodeficiency
  8. Fungal disease
  9. Previous surgery
  10. Depression
  11. Female gender (higher SNOT-22 scores)
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22
Q

What are intraoperative and postoperative management steps for dealing with medial orbit wall compromise/orbital fat herniation during FESS?

A
  1. Avoid suction or manipulation at the site of injury
  2. If a small defect, can be carefully avoided and surgery can proceed
  3. If a large defect, consider aborting surgery
  4. Avoid nasal packing (may result in intraorbital bleed)
  5. Ophthalmology consult if consdered
  6. No nose blowing for 2 weeks post-op (avoid pneumo-orbita)
  7. Exposed fat will re-mucosalize within 2 weeks
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23
Q

What are the AAO-HNS indications for image-guidance in FESS? 7

A
  1. Revision sinus surgery
  2. Distorted sinus anatomy (either developmental, postoperative, or traumatic)
  3. Extensive sinonasal polyposis
  4. Pathology involving frontal, posterior ethmoids/sphenoid sinuses
  5. Disease abutting skull base, orbit, optic nerve, or carotid
  6. CSF rhinorrhea or skull base defects
  7. Benign or malignant sinonasal tumors

“TRACE IT”
Tumor
Revision
Abutting CB/optic/orbit/carotid
CSF leak or skull base defect
Extensive nasal polyposis
In the frontal/sphenoid/post-ethmoid
Twisted (distorted anatomy)

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24
Q

What are contraindications to an endoscopic approach for resection of sinonasal tumors? 6

A

Contraindication: Tumor is not completely accessible via an endonasal approach

Examples:
1. Hard palatal involvement
2. Periorbital involvement
3. Intracranial involvement
4. Infratemporal fossa involvement
5. Cutaneous skin involvement
6. Extensive frontal sinus involvement

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25
Q

What are additional surgical options for CRS in children? 3

A

Questionable efficiency:
1. Tonsillectomy
2. Antral lavage
3. Inferior meatal antrostomy

Probable efficiency:
1. Adenoidectomy (70% successful, first line)
2. Middle meatus antrostomy/balloon sinuplasty
3. Anterior ± posterior ethmoidectomy

Note:
- Frontal sinuses are not developed in children
- Sphenoid is rarely diseased in children

26
Q

Describe the endoscopic 3 pass technique to examine all areas of the nasal cavity

A

First Pass:
- Scope passed along the floor of nasal cavity into nasopharynx
- Structures visualized: Inferior turbinate, inferior aspect of middle turbinate, nasopharynx, eustachian tube torus

Second Pass:
- Scope passed between the inferior and middle turbinate into the middle meatus and then medial to the middle turbinate to look at the sphenoethmoidal recess
- Structures visualized: Septal relationship with middle turbinate, superior turbinate, sphenoethmoidal recess/sphenoid os

Third pass:
- Scope is passed into middle meatus and lateral to the middle turbinate to assess the maxillary antrum and for the presence of accessory fontanelles
- Structures visualized: Lateral portion of middle turbinate
- Accessory fontanelles

27
Q

List in order the 4 vertical lamellae that are passed during an approach to the sphenoid sinus.

What are the 4 consistent bony landmarks during FESS, and 3 inconsistent landmarks?

A

4 vertical lamellae on approach to sphenoid:
1. Uncinate process
2. Bulla ethmoidalis
3. Basal lamella of the Middle turbinate
4. Superior turbinate

Messerklinger’s FESS landmarks:

Consistent:
1. Uncinate process
2. Ethmoid bulla - anterior wall
3. Middle turbinate: Basal Lamella
4. Sphenoid face

Inconsistent:
1. Ethmoid bulla - posterior wall
2. Superior turbinate basal lamella
3. Supreme Turbinate basal Lamella

Vancouver 407

28
Q

What are 6 useful landmarks for revision FESS?

A
  1. Skull base
  2. Superior attachment of middle turbinate
  3. Sphenoid sinus ostiium
  4. Maxillary ostium
  5. Roof of maxillary sinus
  6. Lamina papyracea
29
Q

Discuss the management of an orbital hematoma

A

VISUAL ACUITY ASSESSMENT:
- Colour vision usually first to go
- Ophtho consultation

CONSERVATIVE STRATEGIES:
- Remove nasal packing if any
- Elevate head of bed

MEDICAL STRATEGIES:
- Mannitol
- Acetazolamide
- Dexamethasone
- Timolol eye drops

SURGICAL STRATEGIES:
- Lateral canthotomy + cantholysis
- May also cut Whitnall’s ligement (above)
- May also cut Lockwood’s ligament (below)
- May also consider medial orbital decompression (endoscopic) if retractory to above

Kevan Page 58

30
Q

Your post-op ESS patient develops a post-operative orbital hematoma. What are your management considerations?

A
  1. Fast (Arterial) 15-30 min vs. slow (venous - orbital veins
  2. Hematoma formation (60-90min)
  3. Indications for immediate surgical intervention: Proptosis, Pupil changes (dilated), Chemosis, Vision loss (color vision red first to be lost)
  4. Eye: Consult ophthalmology, assess vision, measure intraocular pressure (>40 absolute indication for lateral canthotomy and cantholysis)
  5. Remove packing and suction at bleeding site
  6. Mannitol 1-2g/kg in 20% IV infusion (100g in 500cc bag) over 20 minutes
  7. Acetazolamide (Diamox) - 500mg IV q4h PRN (decreases aqueous humor production, sulfa drug - potential for allergies)
  8. Timolol 0.5% ophthalmic drops (only if slow bleed)
  9. Steroids
  10. Orbital massage (controversial
  11. Surgical treatment: Lateral canthotomy/cantholysis; Medial external (lynch) decompression; endoscopic decomression of the lamina papyracea
  12. CT after to check hematoma and skull base injuries
  13. If anterior or posterior ethmoid artery is suspected, consider post-op CT sinus to rule out concomitant skull base injury

“OHHH SHIT”
Ophthalmology consult
Help – call for it!
How is the vision?
Help relieve pressure: take out packing
Setup for canthotomy + cantholysis
HOB elevation
IV meds: mannitol, acetazolamide, steroids
Timolol eye drops

31
Q

Discuss the physiology of CSF and ICP:
What is normal ICP pressure?
What is normal CSF volume?
What is the homeostatic mechanisms of CSF - where is it produced and absorbed? What is the rate of production?
What are the functions of CSF? 3
What is the Monroe-Kellie Doctrine?

A

CSF bathes and supports the brain

Normal ICP pressure: 5-15cm H2O
Total CSF volume = 140mL (difference between Cummings vs. Baileys)
- 20-30mL in ventricles
- 50-80mL in intracranial subarachnoid space
- 30-70mL in paraspinal subarachnoid space

CSF Homeostasis:
- Produced in the choroid plexus within the ventricles
- Absorbed by the arachnoid villi
- Production is at a constant rate of 500mL daily

Functions:
1. Cushioning and protective properties
2. Distributes micronutrients
3. Moderates intracranial pressure
- Absorption by the arachnoid villi is via a hydrostatic mechanism; the higher the ICP, the more CSF is absorbed
- Monro-Kellie Doctrine: The sum of the volumes of the Brain + CSF + Intracranial blood = CONSTANT
- Thus, an increase in brain volume (e.g. edema) must cause a decrease in volume of either of the other 2 (e.g. decreased CSF)

32
Q

What are the causes of CSF leak Rhinorrhea?

A

TRAUMATIC (>90%)
1. Accidental Trauma (80%)
- Immediate
- Delayed
2. Surgical Trauma (20%)
- Neurosurgical procedures (e.g. transsphenoidal hypophysectomy, frontal craniotomy, SB procedures)
- Rhinologic procedures (e.g. sinus surgery, septoplasty, combined skull base procedures)

NON-TRAUMATIC (< 10%)
1. Elevated ICP
- Intracranial neoplasm
- Hydrocephalus (non-communicating vs. obstructive)
- Benign intracranial hypertension

  1. Normal ICP
    - Congenital anomaly (e.g. Sternberg’s canal)
    - Skull base neoplasm (e.g. Nasopharyngeal cancer, Sinonasal malignancy)
    - Skull base erosive process (e.g. mucocele, osteomyelitis)
    - Idiopathic
33
Q

What is the typical presentation of a CSF rhinorrhea/leak? 7

A
  • Unilateral clear rhinorrhea
  • Morning headaches, nausea, vomiting
  • Positional rhinorrhea
  • History of head/facial trauma
  • History of sinus or skull base surgery
  • Anosmia/hyposmia/parosmia
  • Recurrent bacterial meningitis
34
Q

How is CSF leak (rhinorrhea) typically diagnosed? Discuss clinical findings, lab tests, CSF tracers, and imaging findings.

A

Clinical Findings:
- Halo sign (fluid)

Lab Tests (of fluid):
1. Glucose (not as accurate)
2. Beta-2-transferrin
3. Beta-trace protein

CSF TRACERS:
1. Intrathecal Fluorescein
- 0.1mL of 10% fluorescein mixed with 10mL of CSF
- Infused into subarachnoid space and used to identify leaks intraoperatively
- Not approved by FDA for intrathecal use (off-label)

  1. Radionucleotide Cisternography (aka. pledget study)
    - Endoscopic placement of pledgets throughout the paranasal sinuses
    - Intrathecal radiotracer is then injected
    - Pledgets are then removed 6-24 hours later and examined for radiotracer activity compared to serum

IMAGING:
1. High resolution CT scan (best initial imaging study)
2. CT Cisternography (Intrathecal injection of contrast followed by imaging)
3. MR Cisternography (Non-invasive, no LP required unlike CT Cisternography; requires active leak and may miss small skull base defects)

35
Q

What is the management for CSF leaks? (Rhinorrhea) What are 5 surgical management indications?

A

CONSERVATIVE:
1. Elevate head of bed
2. Strict bed rest
3. Stool softeners (avoid valsalva)
4. Avoid straining, valsalva, sneezing, nose blowing, coughing

MEDICAL MANAGEMENT:
1. Consider Acetazolamide 500mg PO BID (decreases CSF production)
2. Prophylactic antibiotics NOT recommended, but controversial
3. Lumbar puncture - subarachnoid drainage through lumbar catheter/drain

SURGICAL MANAGEMENT INDICATIONS:
1. Traumatic CSF leak with major neurologic injury
2. Traumatic CSF leak without major injury that persists for more than 7 days
3. Intraoperative CSF leak
4. Persistent iatrogenic CSF leak despite conservative management
5. All non-traumatic CSF leaks

Surgical Management: Multi-layer closure with surgery is ideal

Kevan Page 60 Management strategy

36
Q

Where are 4 places that beta-2-transferrin can be found in the body?

A
  1. CSF
  2. Aqueous and vitreous humor
  3. Perilymph
  4. Serum of some people with specific genetic mutation
37
Q

What are 7 Complications of intrathecal Fluorescein?

A

More severe side effects with large doses (100-700mg)
1. Headaches
2. Nausea/vomiting
3. Dizziness
4. Neurologic deficits
5. Grand mal seizures
6. Pulmonary edema
7. Death

38
Q

What are weak points of the skull base that are prone to dehiscence and CSF leak?

A
  1. Lateral lamella of the cribriform plate
  2. Sternberg’s canal (persistent craniopharyngeal canal that connects to the lateral sphenoid recess)

Kevan Page 61

39
Q

What is the differential for watery rhinorrhea?

A
  1. CSF leak
  2. Vasomotor rhinitis
  3. Allergic rhinitis
40
Q

What is the mechanism of action of Tisseel?

A

Tisseel = Fibrin glue
2 components:
1. Human fibrinogen
2. Human thrombin

MOA: Creates stable fibrin clot (fibrinogen –> fibrin with action of thrombin)

41
Q

Label Kevan Page 61 the lateral and septal nasal wall

A

Lateral:
1. Sphenopalatine artery
2. Cribriform plate
3. Greater palatine artery

Septum:
1. Incisive foramen
2. Sphenopalatine artery
3. Greater palating artery
4. Superior labial artery

42
Q

What is the risk associated with Anterior Ethmoid Artery injury intraop?

A

Retracts into the lamina, and risk of retrobulbar hematoma (orbital hematoma).

Often case is you’re working along the frontals and then Knick the AEA, hard to control cuz you can’t see the bleeding cuz it retracts. Then it stops bleeding cuz of the retraction, and in PACU patient coughs and then develops large orbital hematoma

43
Q

How is a carotid injury managed intraop from FESS surgery?

A
  1. Alert anesthesia to initiate a massive transfusion protocol
  2. Control the surgical field
    - Two large bore (10F) suctions
    - Lens cleaning system (if available)
    - Two surgeons: one manages the suction and the other the camera and attempts to control bleeding
  3. Hemostasis
    - Do not pack tightly with gauze - too much pressure on ICA can cause vasospasm and eventually pseudoaneurysm
    - Muscle patch (SCM or thigh) - 2x2.5x1 cm –> crush it, place it overtop, but do not compress (takes ~12 minutes to work). Generally works well with muscle, then post op need CTA etc. to ensure no pseudoaneurysm.

Other options:
1. Direct vessel closure with a clip
2. Endovascular occlusion
3. Carotid ligation in the neck

44
Q

What is the risk post op if you take down the concha bullosa during a FESS?

A

May develop synechiae between the middle turbinate and lateral wall and cause breathing issues

45
Q

What are 6 risk factors that make patients more prone to complications in FESS?

A
  1. General anesthesia (lack of patient feedback)
  2. Extent of disease
  3. Amount of bleeding
  4. Left orbit for a right handed surgeon
  5. Revision FESS
  6. Expertise of surgeon
46
Q

Discuss all the possible complications of FESS

A

A. INTRACRANIAL
1. CSF
2. Tension pneumocephalus
3. Meningitis
4. Abscess
5. Hemorrhage
6. Encephalocele
7. Direct brain injury

B. ORBITAL
1. Nasolacrimal duct injury
2. Enopthalmos
3. Diplopia (medial rectus injury)
4. Emphysema
5. Fat herniation
6. Ecchymosis
7. Blindness (optic nerve injury)

C. BLEEDING
1. Small amount not requiring transfusion
2. Hematoma
3. Damage to anterior ethmoidal, sphenopalatine, or internal carotid arteries
4. Requirement of transfusion

D. OTHER
1. Hyposmia
2. Mild asthma exaceration
3. MRSA infection
4. Hypesthesia of the infraorbital nerve or teeth
5. Synechiae
6. Atrophic rhinitis
7. Osteitis
8. Packing related / Toxic Shock
9. Death

47
Q

Discuss Toxic Shock Syndrome and how is it treated?

A
  • Complication of prolonged nasal packing
  • Prevented with use of antibiotics for any patient with nasal packing

MOA:
- Staph TSS toxin 1: Non-selective binding to T-cell receptors and acts as a super antigen (stimulates release of +++ inflammatory cells, interleukins, triggers massive inflammatory cascade)

48
Q

How long is the nasolacrimal duct and how do you treat its injury?

A
  • Length ~9mm
  • DacryoCystoRhinostomy if no resolution

https://www.drugs.com/cg/dcr-dacryocystorhinostomy.html

49
Q

Define Myospherulosis

A

Foreign body reaction to the petroleum ointment used in packing

50
Q

What is normal intraocular pressure?

A

Normal IOP = 15 ± 3 mmHg

Max = 23

> 40 = absolute indication for lateral canthotomy and cantholysis

51
Q

What is Brown’s syndrome? What are the causes?

A

BROWN’S SYNDROME:
- Limited elevation of the eye during adduction of the eye
- Due to malfunction of superior oblique muscle (travels through the trochlea, then medial to lateral
- Idea is that there is scarring/tethering/something going on with the trocheal-SO complex that prevents the eye from moving up

CAUSES:
- Congenital or acquired
- Acquired:
1. Injury to superior oblique during FESS
2. Orbital Floor fractures
3. Sinusitis

Treatment:
1. Strabismus surgery

52
Q

What is Anisocoria?

A
  • Dilation of the pupil secondary to local anesthetic in the nasal cavity
  • Can also be congenital
  • Differentiated from early orbital hematoma by the lack of proptosis (optic nerve causes pupil to constrict, with OM nerve)
53
Q

What are the 7 indications for external frontoethmoidectomy?

A
  1. Frontoethmoid mucopyocele
  2. Orbital complication of sinusitis
  3. Revision surgery with absent or distorted landmarks
  4. CSF leak repair
  5. Biopsy of anterior skull base lesion - frontal, orbital, or ethmoid lesion
  6. Access to the anterior ethmoid artery
  7. Facial bone fractures

MORBid FACe
Mucopyocele
Orbital complication of sinusitis
Revision surgery with absent/distorted landmarks
Biopsy of anterior SB lesion
Facial bone fractures
Access to anterior ethmoid artery
CSF leak repair

54
Q

What are 12 complications of external frontoethmoidectomy?

A
  1. CSF leak
  2. Intracranial hemorrhage
  3. Bleeding/crusting
  4. Orbital hemorrhage
  5. Diplopia or blindness
  6. Telecanthus
  7. Epiphora
  8. Persistent or recurrent disease
  9. Mucocele
  10. Stenosis/synechiae of frontal recess with frontal sinusitis
  11. Scarring/keloid formation
  12. Forehead dysesthesia
55
Q

What are three approaches to a frontal mucocele?
What are the advantages and disadvantages of each?

A

Principle of operating on mucoceles is surgical decompression, no need to remove lining

  1. ENDOSCOPIC
    - Advantages: All intranasal (no external incisions)
    - Disadvantages: Cannot access sinuses to eradicate mucosa, limited access laterally
  2. LYNCH FRONTOETHMOIDECTOMY
    - Ethmoidectomy plus removal of entire frontal sinus floor
    - Incision is a 1.5-5cm curvilinear cut from inferior end of eyebrow to inferior orbital rim, midway between the medial canthus and nasal dorsum
    - A Z-plasty may be included to reduce the risk of bowstringing
  3. OSTEOPLASTIC FLAP
    - Advantage: Eradication of disease and mucosa
    - Disadvantage: Requires coronal or mid-forehead approach; disfiguring; high rate of mucocele recurrence

Note: frontal mucocele eroding through posterior table of frontal sinus - you cannot obliterate or cranialize the frontal sinus, because you cannot strip mucosa from the dura!

Vancouver 449

56
Q

What are 6 indications for an osteoplastic flap of the frontal sinus?

A
  1. Chronic frontal sinusitis with persistent intractable symptoms, sepsis, or other complications despite previous intervention
  2. Mucocele with orbital or intracranial extension
  3. Osteomyelitis
  4. Frontal sinus tumor
  5. Frontal sinus fracture with comminuted anterior table or displaced posterior table
  6. CSF leak

MOST CsF
Mucocele with orbital or intracranial extension
Osteomyelitis
Sinusitis chronic persistent intractable
Tumor of frontal sinus
CSF leak
Fracture

57
Q

What are 6 contraindications for osteoplastic flap obliteration of the frontal sinus?

A

“PHOBIA”

  • P: Posterior table erosion
  • H: Hyperpneumatized supraorbital ethmoid cells
  • O: Orbital roof dehiscence
  • B: Bad tumor / frontal sinus tumor
  • I: Inverted papilloma
  • A: AFRS or other fungal sinusitis
58
Q

What are the planes of dissection for a pericranial (osteoplastic) flap for frontal sinus obliteration?

A
  1. Subgaleal dissection (the supraorbital and supratrochlear arteries run on the surface of the galea)
  2. Superficial layer of deep temporal fascia - overlying temporalis muscle (superficial temporal artery runs in superficial layer)
59
Q

Describe the general steps in performing a frontal sinus obliteration procedure with an osteoplastic flap

A
  1. Bicoronal incision (most widely used approach. Other approaches: midforehead, direct eyebrow)
  2. Raise the bicoronal flap
  3. Borders of frontal sinus are identified and marked out
  4. Holes for future miniplate application are made
  5. Periosteum is incised 1cm outside the markinig of the frontal sinus superiorly and laterally, but left undisturbed inferiorly (for blood supply of the osteoplastic flap)
  6. Drill holes outlining the frontal sinus are made and connected with a sagittal osteotome
  7. Osteoplastic flap is reflected forward
  8. Frontal sinus is obliterated by:
    - Stripping mucosa
    - Drilling polishing the anterior and posterior table
    - Obliteration with fat, bone, vascularized pericranium flap, hydroxyapatite cement

9.Osteoplastic flap fixed with miniplates and skin sutured

60
Q

What are methods of localizing the frontal sinus intraoperatively? (e.g. during obliteration?) 4

A
  1. Transillumination via frontal trephine - shining a light with an endoscope transnasal
  2. Intraoperative image guidance
  3. Using a wire probe as a guide through a frontal trephine
  4. Plain film overlay (caldwell view) - obtained from a distance of 6 feet
61
Q

What are five historical open frontal sinus procedures?

A
  1. Reidel - Removal entire floor and anterior wall of frontal sinus; significant cosmetic deformity
  2. Killian - Combination of Reidel and lymch; removal of floor and anterior wall, retain frontal bar
  3. Lynch - Ethmoiidectomy plus removal of entire frontal sinus floor, and part of the lamina papyracea
  4. Lothrop/Chaput-Mayer - Superior nasal septum and inner sinus septum taken down