1
Mucoceles
Mucoceles
of the
of the
Paranasal
Paranasal
Sinuses
Sinuses
Francis T.K. Ling, MD BSc
Department of Otolaryngology – Grand Rounds
University of Ottawa
Wednesday, January 28
th
2004
Overview
Overview
• Anatomy and Development
• Physiology and Pathophysiology
• Epidemiology
• Clinical Features
• Treatment
• Case Presentations
Introduction
Introduction
• Definition:
• Epithelial lined mucous-containing sac completely filling a
paranasal sinus
• Capable of expansion by virtue of bone resorption and new bone
formation
Introduction

• Ethmoid Sinuses
• Located in superior half of
lateral nasal wall
• Development begins during 3
rd
-
4
th
month of fetal development
• Continue to grow through
childhood until age 12
• Average volume 15 ml
• Drainage:
• Anterior: infundibulum or
ethmoid bulla
• Posterior: superior meatus
Anatomy and Development
Anatomy and Development
• Sphenoid sinus
• In body of sphenoid bone
• No significant sinus at birth
• Development begins at 5 years
• Final volume attained by 12-15
years
• Average volume: 7.5 ml
• Drainage:
• Sphenoethmoidal recess
Anatomy and Development
Anatomy and Development
• Frontal Sinuses

to natural ostium
• Frontal: inward flow
medially  superior 
lateral  floor  frontal
recess
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Pathophysiology
Pathophysiology
• Obstruction of sinus ostium or outflow tract
• Inflammation (ie. Chronic sinusitis)
• Trauma
• Iatrogenic (eg. FESS)
• Mass/Tumour (eg. Polyps, ostioma, malignancy, ostioma)
• Obstruction of minor salivary gland located within lining
of paranasal sinus
• Eg. Mucous retention cyst of maxillary sinus
Pathophysiology
Pathophysiology
• Bone resorption:
• Epithelium continues to secrete
causing expansion of the mucocele
• Increased pressure 
devascularization of bone and
osteolysis
• Local inflammation  secretion of
cytokines
• Fibroblasts  PGE2 + IL-1
• Epithelial cells  TNF alpha
• Cause osteoclastic bone
resorption

• In general:
• Headache and facial pressure common
• Facial swelling with tenderness to palpation
• Ocular and neurological problems
Fronto
Fronto
-
-
ethmoidal Mucocele
ethmoidal Mucocele
• Most common clinically significant mucocele
• Classification (Har-El, 2001)
• Type 1: Limited to frontal sinus (+/- orbital extension)
• Type 2: Frontoethmoid mucocele (+/- orbital extension)
• Type 3: Erosion of posterior wall
• A. Minimal or no intracranial extension
• B. Major intracranial extension
• Type 4 Erosion of anterior wall
• Type 5 Erosion of both posterior and anterior wall
• A. Minimal or no intracranial extension
• B. Major intracranial extension
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Fronto
Fronto
-
-
ethmoidal Mucocele
ethmoidal Mucocele
• General:
• Frontal headache (common) and/or deep nasal pain

Mucocele
Mucocele
• “mucous-retention” cyst
• Incidental finding
• Rarely achieve sufficient size to cause bony erosion
• Rarely require specific therapy if asymptomatic
• Spontaneous regression without therapy
Sphenoid
Sphenoid
Mucocele
Mucocele
• Rare lesion
• Extension:
• Superiorly into pituitary fossa  intracranial
• Posteriorly towards clivus
• Anteriorly into posterior ethmoids
• Laterally into orbits
• Compression:
• Pituitary gland, optic chiasm, carotid artery, cavernous sinus, CN
III-VI, brain
Sphenoid
Sphenoid
Mucocele
Mucocele
• General:
• Headache with occipital, vertex or deep nasal pain
• Ocular:
• Diplopia
• Visual field disturbance
• Vision loss

• Surgery is required
• Operate on non-infected mucocele unless acute
symptomatic mucopyocele
• Goals
• Reintegration of affected sinus into nasal circuit
• Sinus exclusion with obliteration and respect of posterior wall
• Cranialization
• Approaches
• External
• Endoscopic
• Combined
External Approaches
External Approaches
• Traditionally preferable when there are intraorbital or
intracranial manifestations
• Typically for fronto-ethmoidal mucoceles
• Techniques:
• External frontoethmoidectomy
• Lynch
• Killian
• Reidel
• Lothrop
• Osteoplastic flap
External
External
Frontoethmoidectomy
Frontoethmoidectomy
• Indications:
• Acute infectious of frontal and ethmoid sinuses with orbital
extension

External
External
Frontoethmoidectomy
Frontoethmoidectomy
• Killian procedure
• For tall sinuses in which
disease cannot be removed
through floor alone
• Floor and anterior wall
removed
• Supraorbital bony strut (10
mm)
External
External
Frontoethmoidectomy
Frontoethmoidectomy
• Reidel procedure:
• Entire anterior wall and floor
of frontal sinus removed
• Mucosa removed
• Sinus obliteration 
forehead soft tissue laid
against posterior table
• Significant deformity
• Rarely if ever used
External
External
Frontoethmoidectomy
Frontoethmoidectomy
• Lothrop procedure:

• Brow incision
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Osteoplastic
Osteoplastic
Flap
Flap
• Technique:
• Skin-tissue flap raised,
preserving periosteum and
supraorbital nerves
• Perimeter of frontal sinus
marked with template from
Caldwell-view radiograph
Osteoplastic
Osteoplastic
Flap
Flap
• Technique:
• Periosteum incised and lifted
off bone
• Bone cuts made to create
osteoplastic flap
Osteoplastic
Osteoplastic
Flap
Flap
• Technique:
• Bone flap removed
• Disease in frontal sinus
removed

with fascia, muscle or bone
Osteoplastic
Osteoplastic
Flap
Flap
• Technique:
• Bone flap replaced and fixed
• Periosteum closed
• Skin closure
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Osteoplastic
Osteoplastic
Flap
Flap
• Cranialization
• Indications:
• Large portions of posterior frontal sinus destroyed with
substantial epidural spread of mucocele
• Intracranial complications present
• Frontal craniotomy usually required
• Extradural dead space remains for extensive mucoceles
• Dead space obliterates by frontal brain over several weeks
• Oblteration of dead space by abdominal fat used to achieve
immediate closure and to avoid scarred adhesions
Osteoplastic
Osteoplastic
Flap
Flap
• Complications:
• Fat donor site:

• Facial nerve  loss of frontalis function
• Olfactory nerve  anosmia
• Cosmesis:
• Scar
• Depression or embossment
• Recurrence
External Approaches
External Approaches
• Recurrence:
• Lund (1998):
• 28 patients with combined approach (Lynch)
• Recurrence rate: 11%
• Weber (2000):
• Osteoplastic flaps for various reasons
• 59 patients
• Mucoceles after procedure: 9.8% (5 patients)
• Conboy and Jones (2003)
• 23 patients with external (Lynch) or combined approach
• 26% recurrence
Endoscopic
Endoscopic
Approach
Approach
• Introduced in 1980 by D.W. Kennedy
• “marsupialization”:
• Opening enlarged without complete removal of mucosal lining
• Lund (1991):
• Sinus lining returns to normal with re-establishment of
mucociliary activity
• Advantages:

• Technique:
• Identification of anterior
ethmoid artery
• Posterior reference
• Frontal opening located
2-4 mm anterior
Endoscopic
Endoscopic
Approach
Approach
• Technique:
• Agger nasi
cells removed
Endoscopic
Endoscopic
Approach
Approach
• Technique:
• Enlargement
anteriorly and
anteriormedially to
avoid accidental
intracranial entry
Endoscopic
Endoscopic
Approach
Approach
• Technique:
• Mucosa covering
posterior aspect of

• 178 patients with 3 recurrences
• 97.9% successful
• Lund et al; J. Laryngol. Otol. 112(1): 36-40, 1998
• No recurrences in 20 patients
• Mean follow-up 34 months
Endoscopic
Endoscopic
Approach
Approach
• Results (Cont’d):
• Har-El; Laryngoscope 111:2131-2134, 2001
• 108 sinus mucoceles
• 66 frontal and frontoethmoidal, 17 ethmoid, 7 sphenoethmoid,
12 sphenoid, 6 maxillary mucoceles
• 83% intraorbital extension
• 55% erosion of skull base with varying degrees of intracranial
extension; 31% major intracranial extension (intracranial
extent larger than sinus
• Follow-up: 1-13.5 years; median 4.5 years
• Recurrence of frontal mucocele in 1 patient (0.9%)
Endoscopic
Endoscopic
Approach
Approach
• Results (Cont’d):
• Conboy and Jones; Clin. Otolaryngol. 28:207-210, 2003
• 68 mucoceles
• 66% endoscopic, 22% external, 12% combined
• Mean follow-up 6 years
• Recurrences:

invasive and can provide an adequate surgical view for
wide marsupialization”
Follow
Follow
-
-
up
up
• Mucoceles may recur many years after surgery
• Recurrences may be as long as 49 years after initial surgery
(Moriyama)
• Recurrences should be treated as early as possible
Case Presentation #1
Case Presentation #1
• 69 yo M
• Pituitary tumour removed 25 years ago
• Follow-up MRI  incidental left frontal mucocele
• No orbital or intracranial extension
• Asymptomatic with no sinus complaints
Case Presentation #1
Case Presentation #1
Case Presentation #1
Case Presentation #1
• Dx: Frontal mucocele
• Treatment:
• Endoscopic removal of left frontal sinus mucocele
• Marsupialization and aspiration of thick fluid
• Well postoperatively
• No complications
• No recurrence

• Well postoperatively
• Reduced pain
• Vision still decreased
• No recurrence at 4
months
Case Presentation #3
Case Presentation #3
• 73 yo M
• History of chronic sinusitis
• Previous septoplasty
• Admitted for nausea and vomiting, dehydration, frontal
headaches and diplopia
• Previously on antibiotics and pain medication with no
improvement in symptoms
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Case Presentation #3
Case Presentation #3
Case Presentation #3
Case Presentation #3
Case Presentation #3
Case Presentation #3
Case Presentation #3
Case Presentation #3
• Dx: sphenoethmoidal
mucocele
• Treatment:
• FESS
• Middle turbinate fractured to
expose large cystic formation
• Aspiration of purulent

• Patient not interested in craniotomy for biopsy or
decompression
• Will be followed regularly
Case Presentation #4
Case Presentation #4
• 49 yo M
• Progressive proptosis of
right eye
• No visual deficits
• Investigations:
• Large right frontal sinus
lesion
• Extension into orbit and
intracranial cavity
Case Presentation #4
Case Presentation #4
• Dx: Right frontal mucocele
• Treatment:
• Combined ENT, Ophthalmology and Neurosurgery removal
• Osteoplastic flap
• Brow incision
• Supraorbital nerve cut for exposure
• Template  osteoplastic flap raised  mucocele evacuated
• Roof of orbit and posterior sinus wall eroded
• Mucocele lining removed, sinus walls burred
Case Presentation #4
Case Presentation #4
• Treatment (Cont’d)
• Osteoplastic flap:
• Dura dehiscent anteriorly with exposed brain  dural patch

• Traditionally, complete removal advocated via external approach
• Trend towards endoscopic management
• External or combined approaches usually reserved for extensive
involvement or failed endoscopic attempt
• Push towards endoscopic management of large intracranial
mucoceles
• Long term follow-up required to monitor for recurrence