See Also: Medical Management of Sinusitis 

Content prepared by Evgeniya Molotkova and Drs. Ryan Thorpe and Jarrett Walsh (12/9/24)

 

Abbreviations

CRS: chronic rhinosinusitis

CRSwNP: chronic rhinosinusitis with nasal polyps

CRSsNP: chronic rhinosinusitis without nasal polyps

CT: computed tomography

 

Background

• The most common chronic inflammatory disease in the world, affecting up to 10% of the world’s population (Kato et al, 2022)
• Diagnostic criteria for chronic rhinosinusitis (CRS) (Orlandi et al, 2021)
  • Greater than (or equal to) 12 weeks of nasal discharge, nasal obstruction/congestion, hyposmia, facial pressure/pain, and/or cough (in pediatric CRS only)
    • AND evidence of inflammation on nasal endoscopy/CT or evidence of purulence coming from paranasal sinuses or ostiomeatal complex
    • AND divided into CRSwNP CRSsNP depending on presence/absence of nasal polyps (respectively)
• Pathogenesis of CRS
  • The sinonasal epithelial layer has both passive and active roles in the immune response (Kato et al, 2022)
    • Passive structural changes:
      • Studies have shown that breakdown in the sinonasal epithelial layer enhances exposure to immunogenic antigens (Kato et al, 2022)
    • Active structural changes:
      • Altered mucociliary clearance, changes in bacterial microbiome, and activation of inflammatory pathways (Michalik et al, 2024)
• Clinical phenotypes (Cho et al, 2020)
  • Chronic rhinosinusitis WITH nasal polyps (CRSwNP)
    • Variable, inflammatory, chronic process
  • Chronic rhinosinusitis WITHOUT nasal polyps (CRSsNP)
    • Typically a type 2 helper T cell (Th2) predominant, eosinophilic inflammatory process, but may vary (Orlandi et al, 2021)
• Clinical endotypes (type 1, 2, and 3) (Orlandi et al, 2021)
  • Categorizes CRS based on the type of immune response and inflammation predominates
    • Type 1: mediated by Th1 cells with predominant biomarkers interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α)
    • Type 2: mediated by Th2 cells with predominant biomaerkts interleukin 4 (IL-4), interleukin 5 (IL-5), interleukin 13 (IL-13), eosinophil cationic protein (ECP), and P-glycoprotein (P-gp)
    • Type 3 : mediated by Th17 cells and interleukin 17A (IL-17A)

 

General Considerations

• Indications
  • Failure of symptomatic improvement with appropriate medical therapy (Orlandi et al, 2021) See also: Medical Management of Sinusitis
    • Previous studies out of the US and UK have demonstrated that patients who receive surgery for CRS sooner rather than later in relation to their initial diagnosis tend to have a greater improvement in their symptoms
  • Patient selection
    • Patients with a SNOT-22 score ≥ 20 will most likely achieve benefit from surgery (Orlandi et al, 2021)
      • However, this may exclude patients with lower scores that could also benefit from surgery
• Pertinent Anatomy
  • Blood supply
    • Frontal (McLaughlin et al, 2001)
      • Internal carotid artery > ophthalmic artery > anterior ethmoid artery
      • In some cases, the frontal sinuses are supplied by the supraorbital branch of the ophthalmic artery instead
    • Ethmoid (Ogle et al, 2012)
      • Supplied by the ethmoidal arteries (anterior and posterior) branching off the ophthalmic artery
    • Maxillary (Ogle et al, 2012)
      • Anastomoses between infraorbital, sphenopalatine, posterior lateral nasal, facial, pterygopalatine, greater palatine, and posterior superior alveolar arteries
  • Innervation
    • Frontal (McLaughlin et al, 2001)
      • Parasympathetic (affecting secretory functions): superior salivatory nucleus > greater petrosal nerve > nerve of the pterygoid canal > pterygopalatine ganglion >  lateral posterior superior nasal nerves
      • Sensory:  trigeminal nerve > nasociliary nerve (V1) > anterior ethmoidal nerve
      • Also trigeminal nerve > frontal nerve (V1) > supraorbital and supratrochlear branches
    • Ethmoid (Ogle et al, 2012)
      • Sensory: trigeminal nerve > ophthalmic nerve (V1) > anterior and posterior ethmoid nerves
      • Also, trigeminal nerve > maxillary nerve (V2) > posterior nasal branch
    • Maxillary (Ogle et al, 2012)
      • Anterior superior, middle superior, and posterior superior alveolar nerves
  • Anatomic relationships to consider (Orlandi et al, 2021)
    • Maxillary:ethmoid ratio
      • Measured in the coronal plane
      • Ratio of maxillary height to the ethmoid (posterior to basal lamella)
      • Injury to the skull base is more likely in patients with a ratio greater than 1:1
    • Keros classification
      • Measured in the coronal plane
      • Refers to length of the lateral lamella relative to fovea ethmoidalis
        • Keros I: 1-3 mm
        • Keros II: 4-7 mm
        • Keros III: 8-16 mm
      • Risk for intracranial injury is higher in patients with a higher Keros classification
    • Ethmoidal arteries
      • Determination of whether the anterior and posterior ethmoidal arteries are located within or suspended below the skull base
        • Arteries suspended below the skull base are more likely to be injured
    • Sphenoid sinus pneumatization
      • Determination of the pneumatization pattern: conchal, presellar, or sellar
    • Skull base asymmetry/bony dehiscence
      • Inadvertent injury during surgery is more common in cases of asymmetric skull base/bony defects
  • Preoperative imaging is important in the identification of potential anatomic variants that may make sinus surgery difficult or dangerous
  • Adapted from O’Brien and colleagues, 2016 – “CLOSE”
    • Cribriform plate
      • Plane: coronal
      • Evaluate: Keros classification/asymmetry, dehiscence of the skull base
      • Importance: The lateral lamella of the cribriform plate is the thinnest spot and is vulnerable to intraoperative injury, especially during turbinectomy or ethmoidectomy.
    • Lamina papyracea
      • Plane: coronal and/or axial
      • Evaluate: for evidence of remote orbital fracture, orbital prolapse, presence of Haller cell, uncinate process contacting orbital wall
      • Importance: Prior injury can displace the lamina papyracea medially into the ethmoid sinus. This can make it easy to mistake for an ethmoid sinus septation and lead to inadvertent entry into the orbit.
    • Onodi cell
      • Plane: coronal
      • Evaluate: presence/absence of Onodi cell, dehiscence of optic nerve in Onodif cell
      • Importance: This variant of the ethmoid air cells may occasionally contain the optic nerve.
    • Sphenoid sinus pneumatization
      • Plane: sagittal and/or axial
      • Evaluate: pneumatization pattern and pneumatization into skull base/anterior clinoid, carotid canal dehiscence, sinus separation onto carotid canal, optic nerve dehiscence
      • Importance: The sellar pattern of pneumatization results in a thin bony margin to the clivus, making it susceptible to intraoperative injury. Dehiscence of the carotid canal or optic nerve may result in injury to these structures intraoperatively.
    • (Anterior) ethmoidal artery
      • Plane: coronal
      • Evaluate: identify ethmoidal notch, presence/absence of supraorbital pneumatization
      • Importance: If the ethmoidal notch abuts the fovea ethmoidalis or lateral lamella, it is considered largely “protected” during FESS

 

Relevant Techniques

• Historic perspectives and external techniques:
  • Caldwell-Luc technique (Matheny and Duncavage, 2003)
    • Used to clear out diseased tissue from the maxillary sinus, but has largely been supplanted by endoscopic approaches due to higher rates of surgical complications
      • Still used for patients who fail endoscopic surgical management
    • Operative technique:
      • Begins with an gingivolabial incision in the mucosa above the canine tooth
      • An anterior antrostomy is performed to facilitate access to the maxillary sinus contents, which are removed
      • An inferior meatus and/or middle meatus antrostomy is performed to allow post-surgical and physiologic drainage
  • External ethmoidectomy (Stankiewicz, 2015)
    • This approach may still be useful in cases where increased exposure is needed for resection of ethmoid or orbital tumors
      • Due to close proximity to the ethmoidal arteries, this technique carries risk of significant hemorrhage and retrobulbar hematoma
    • Operative technique:
      • A modified Lynch incision is made
        • A curvilinear incision that starts at the inferior border of the medial border of the eyebrow and terminates at the level of the periosteum at the orbit
      • The lamina papyracea is resected and the ethmoid sinus can be directly visualized
  • Frontal sinus trephine (Stankiewicz, 2015)
    • Still performed when endonasal techniques do not provide adequate visualization/access to the frontal sinus
    • Operative technique:
      • An incision is made medial to the eyebrow
      • Overlying soft tissue and periosteum is dissected away, being careful to spare the supratrochlear and supraorbital neurovascular bundles
      • The frontal sinus is accessed using a drill and/or rongeurs
      • The trephine can be used as an avenue to insert endoscopes and/or other instruments
  • Osteoplastic flap (OPF) (Stankiewicz, 2015)
    • Often done in combination with sinus obliteration
    • Operative technique:
      • A bicoronal incision is made and skin/overlying soft tissue is retracted to reveal the frontal bone
      • Image guidance (or if unavailable, a radiograph template of the frontal sinus) is used to make guide holes
      • Cuts are made in the bone to create the osteoplastic flap, which is removed to access the frontal sinus
• Endoscopic sinus surgery (Palmer et al, 2012)
  • Endoscopic nasal exam
    • This is performed before all endoscopic nasal procedures
      • The first pass involves placement of the endoscope at the floor of the nasal cavity, medial to the inferior turbinate, and visualizing the floor of the nasal cavity, nasopharynx, posterior pharyngeal wall, and Eustachian tube opening.
        • The endoscope is redirected medially to the medial meatus to visualize the middle turbinate, osteomeatal complex, and the area of the nasal lacrimal pathway.
      • A second pass is used to view the superior turbinate, superior meatus, sphenoethmoidal recess, and anterior skull base
  • Middle meatal antrostomy
    • The middle meatus is accessed by visualization of the uncinate process and removal by osteotome or balloon dilation. This allows for access to the maxillary sinus
  • Endoscopic medial maxillectomy
    • This describes the process of removing inspissated mucus, inflamed tissue, and benign or malignant masses from the maxillary sinus using a variety of techniques (ex. osteotome, suction removal, and microdebrider)
  • Ethmoidectomy
    • The middle portion of the uncinate process is removed to visualize the bulla ethmoidalis. This allows for removal of the anterior ethmoidal air cells back to the posterior wall of the ethmoid sinus.
  • Sphenoid surgery
    • Done alone or in combination with ethmoidectomy. After the superior turbinate is visualized, the posterior aspect of the superior turbinate is removed to identify the sphenoidal sinus
      • This can allow for access into the sphenoidal sinus and resection of diseased tissue
  • Frontal sinus exploration
    • After completion of ethmoidectomy, the frontal recess is accessed by using the superior aspect of the uncinate process as a landmark. The anterior portion of the middle turbinate may be removed for better visualization. This allows for the frontal recess to be cleared of diseased tissue
• Draf sinusotomy classification, adapted from Weber and colleagues, 2001
  • Type I
    • “Anterior ethmoidectomy with drainage of the frontal recess without touching the frontal sinus outflow tract”
  • Type IIA
    • “Removal of ethmoidal cells protruding into the frontal sinus creating an opening between the middle turbinate medially and the lamina papyracea laterally”
  • Type IIB
    • “Removal of the frontal sinus floor between the nasal septum medially and the lamina papyracea laterally”
  • Type III
    • “Type II drainage on both sides and removal of the upper part of the nasal septum and the lower part of the frontal sinus septum”
• Image-guided surgery
  • Image-guided endoscopic sinus surgery is becoming increasingly common (Beswick and Ramakrishnan, 2020)
  • The American Academy of Otolaryngology – Head and Neck Surgery endorses the use of image-guided surgery with indications including revision surgery, cases of distorted anatomy, and extensive nasal polyps, among others (entnet.org)
  • Studies have shown that the use of image guidance does not improve surgical outcomes, but it may reduce the rates of major and total surgical complications
• Consideration based on CRS subtype (Jaksha et al, 2016)
  • CRSwNP: patients may benefit from more extensive initial surgery
    • Opening all 8 sinuses with variable frontal sinus intervention
    • Goal is to remove diseased tissue and improve sinus drainage and area for drug delivery
• CRSsNP: pathogenesis is typically associated with a more specific anatomic abnormality
  • More conservative approach, addressing underlying abnormality
    • Examples: odontogenic sinusitis, concha bullosa, Haller cells, and accessory ostia

 

Pre-operative Preparation

See Endoscopic Sinus Surgery for discussion of consent, nursing considerations, and anesthetic considerations

 

Post-operative Care

• Complications of endoscopic sinus surgery
  • Minor (May et al, 1994)
    • Periorbital emphysema and ecchymosis (1.7%)
    • Dental and lip pain/numbness and infection (5.4%)
    • Symptomatic adhesions (1.4%)
    • Epistaxis (1.6%)
  • Major (Ramakrishnan et al, 2012)
    • CSF leak (0.17%)
    • Orbital injury (0.07%)
    • Hemorrhage requiring blood transfusion (0.76%)
• Management of steroid eluting stents postoperatively
  • Steroid eluting stents can be inserted into the nose, sinuses, or both to prevent post-operative stenosis and provide anti-inflammatory benefits during the healing process (Huang et al, 2015)
  • Stents can be non-absorbable or absorbable (Huang et al, 2015)
    • Non-absorbable stents are removed several after surgery
    • Absorbable stents are left in and degrade over a period of days to weeks following surgery
  • In a meta-analysis looking at outcomes after endoscopic sinus surgery and steroid-eluting stent placement done by Goshtasbi and colleagues in 2019:
    • Stent duration
      • Bioabsorbable stents were left in for 30 days
      • Nonabsorbable stents were removed anywhere from 21 to 60 days postoperatively
    • Stent steroid
      • Most commonly eluting steroids were mometasone furoate and triamcinolone
    • Antibiotic
      • Several studies included management with a post-operative oral antibiotic
• Post-operative care (Orlandi et al, 2021)
  • Post-operative care interventions are graded based on the amount of supporting evidence available
  • Grade A
    • Topical (nasal) corticosteroids
      • Reduces symptoms postoperatively, prevents polyp regrowth, and improves endoscopic appearance
    • Post-operative packing
      • Aids in both intraoperative and post-operative hemostasis as well as wound healing. Provides additional patient comfort
    • Post-operative drug-eluting implants (stents)
      • See above discussion
  • Grade B
    • Saline irrigation
      • Improves symptoms and endoscopic appearance
    • Sinus cavity debridement
      • Improves symptoms and endoscopic appearance
      • Reduces risk of adhesions and turbinate lateralization
    • Oral antibiotics
      • Reduces symptoms, endoscopic appearance, and nasal crusting
    • Mitomycin C
      • Reduces adhesion formation and improves patency of maxillary ostium
  • Grade C
    • Systemic corticosteroids
      • Not routinely recommended, but may be beneficial in some cases
      • In these select cases, systemic steroids help improve endoscopic sinus appearance as well as reduce/slow polyp regrowth
  • No grade
    • Topical decongestants
      • Potential reduction of swelling and bleeding
      • However, research demonstrates that topical decongestants have a preponderance of harm versus benefit

 

Sample Dictation

Informed consent was reviewed with the patient in the preoperative evaluation area. The patient was brought to the operating room, placed on the operating table in the supine position and transorally intubated. The table was turned 180 degrees and the patient was positioned in the standard fashion. The patient was then draped in a clean fashion. The Stealth image guidance system was then configured according to the manufacturer's instructions and the patient registered with the system. It was utilized throughout the procedure to confirm the location of the skull base, lamina papyracea, and other structures.

Rigid nasal endoscopy was performed on both sides. The bilateral inferior turbinates were lateralized with a Freer elevator. 1% lidocaine and epinephrine 1:100,000 was injected in the bilateral lateral nasal wall and the axilla of the middle turbinates.

Attention was then turned back to left nasal cavity. The middle meatus was visualized and the uncinate was removed with back biting forceps and microdebrider. The natural ostium of the maxillary sinus was identified with a curved suction and a combination of straight ahead thru-cutting forceps, back biter and microdebrider were used to create a large antrostomy. Thick purulence within the maxillary sinus was removed was a suction trap and sent for culture analysis. Microdebrider was used for further widening of the. The maxillary sinus was copiously irrigated and all purulence suctioned.

Left ethmoidectomy was then performed by proceeding through the ethmoid bulla, anterior ethmoid cells and into the posterior ethmoid air cells. The basal lamella and skull base were identified, confirmed with use of image guidance, and the ethmoid air cells and their contents dissected off the skull base in a posterior to anterior direction with a curette, microdebrider and Kerrison punch. The frontal recess was then identified and cleared out, removing the suprabullar ethmoid air cells. Copious irrigation into frontal sinus was performed with suctioning of thick purulence.

The sphenoid rostrum was identified and a sphenoidotomy was created medial and inferior to the attachment of the superior turbinate. The sphenoidotomy was created in a medial and inferior direction. The sphenoid sinus was then explored with a 30-degree telescope and thick purulence and inspissated debris removed with suction and forceps. The sinus was then copiously irrigated and suctioned gently to clear any remaining purulence.

The contralateral side was then addressed in a similar fashion performing identical procedures for the right maxillary antrostomy, complete ethmoidectomy, frontal sinusotomy, and sphenoid sinusotomy with removal of inspissated debris and inflammatory tissue. Hemostasis was obtained with oxymetazoline-soaked cottonoid pledgets and suction cautery. Novapack was placed on both sides of the middle meatus to help stop bleeding and also medialize the turbinates. The nose was then re-examined and hemostasis verified, with oxymetazoline-soaked pledgets placed for removal at time of extubation. Throughout the procedure, the eyes were intermittently examined and were soft to palpation on both sides. The patient tolerated the procedure well, was extubated in the operating room, nasal pledgets removed, and was transferred uneventfully to the post anesthesia care unit.

 

References

Michalik M, Krawczyk B. Chronic Rhinosinusitis-Microbiological Etiology, Potential Genetic Markers, and Diagnosis. Int J Mol Sci 2024; 25.

Cho SH, Hamilos DL, Han DH, Laidlaw TM. Phenotypes of Chronic Rhinosinusitis. J Allergy Clin Immunol Pract 2020; 8:1505-1511.

Orlandi RR, Kingdom TT, Smith TLet al. International consensus statement on allergy and rhinology: rhinosinusitis 2021. International Forum of Allergy & Rhinology 2021; 11:213-739.

Palmer O, Moche JA, Matthews S. Endoscopic surgery of the nose and paranasal sinus. Oral Maxillofac Surg Clin North Am 2012; 24:275-283, ix.

Jaksha AF, Weitzel EK, Laury AM. Recent advances in the surgical management of rhinosinusitis. F1000Res 2016; 5.

Kato A, Schleimer RP, Bleier BS. Mechanisms and pathogenesis of chronic rhinosinusitis. Journal of Allergy and Clinical Immunology 2022; 149:1491-1503.

McLaughlin RB, Jr., Rehl RM, Lanza DC. Clinically relevant frontal sinus anatomy and physiology. Otolaryngologic Clinics of North America 2001; 34:1-22.

Ogle OE, Dym H. Surgery of the nose and paranasal sinuses: principles and concepts. Oral Maxillofac Surg Clin North Am 2012; 24:xiii-xiv.

Position Statement: Intra-Operative Use of Computer Aided Surgery. Available at: https://www.entnet.org/content/intra-operative-use-computer-aided-surgery. Accessed September 18, 2024.

Beswick DM, Ramakrishnan VR. The Utility of Image Guidance in Endoscopic Sinus Surgery: A Narrative Review. JAMA Otolaryngology–Head & Neck Surgery 2020; 146:286-290.

Matheny KE, Duncavage JA. Contemporary indications for the Caldwell-Luc procedure. Current Opinion in Otolaryngology & Head and Neck Surgery 2003; 11:23-26.

Stankiewicz JA. Medical and Surgical Complications in the Treatment of Chronic Rhinosinusitis. Otolaryngol Clin North Am 2015; 48:xv-xvi.

Weber R, Draf W, Kratzsch B, Hosemann W, Schaefer SD. Modern Concepts of Frontal Sinus Surgery. The Laryngoscope 2001; 111:137-146.

Ramakrishnan VR, Kingdom TT, Nayak JV, Hwang PH, Orlandi RR. Nationwide incidence of major complications in endoscopic sinus surgery. Int Forum Allergy Rhinol, 2012; 2:34–39

May M, Levine HL, Mester SJ, Schaitkin B. Complications of endoscopic sinus surgery: Analysis of 2108 patients—incidence and prevention. The Laryngoscope 1994; 104:1080-1083.

Huang Z, Hwang P, Sun Y, Zhou B. Steroid-eluting sinus stents for improving symptoms in chronic rhinosinusitis patients undergoing functional endoscopic sinus surgery. Cochrane Database Syst Rev 2015; 2015:Cd010436.

Goshtasbi K, Abouzari M, Abiri Aet al. Efficacy of steroid-eluting stents in management of chronic rhinosinusitis after endoscopic sinus surgery: updated meta-analysis. Int Forum Allergy Rhinol 2019; 9:1443-1450.

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