Tài liệu Mucoceles of the Paranasal Sinuses pdf

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

Introduction
• Mucoceles known for > 100 years
• 1725: Dezeimeris first described frontal mucoceles
• 1818: Langenbeck commented on clinical complaints and
symptoms
• “hydatids”
• 1890: Rollett introduced the term “mucocele”
• Most common lesion causing expansion of paranasal
sinuses
Anatomy and Development
Anatomy and Development
• Maxillary sinuses
• Ethmoid sinuses
• Sphenoid sinus
• Frontal sinuses
Anatomy and Development
Anatomy and Development
• Maxillary Sinuses
• Occupies body of maxilla
• First to develop in the
human fetus
• Biphasic growth:
• 3 years
• 7 years to adolescence
• Average volume 14.75 ml
• Drains into middle meatus
via maxillary ostium
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Anatomy and Development
Anatomy and Development

• 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

• Frontal bone
• Begins as evagination of frontal
recess
• Development begins at 2 ya and
reaches adult size at 15-20 ya
• Variable development:
• 10% unilateral
• 5% rudimentary
• 4% absent
• Drainage into frontal recess
• 2-20 mm in length
Anatomy and Development
Anatomy and Development
• Frontal recess
• Marked variation in configuration and attachment of uncinate
process
• Variable drainage patterns of frontal recess
Physiology
Physiology
• Sinus lining:
• Ciliated, pseudostratified,
columnar epithelium
• Mucous glands and goblet
cells  mucous blanket
• “sol-gel” phase
Physiology
Physiology
• Pattern of clearance:
• Maxillary: floor 
stellate pattern along walls

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

Epidemiology
Epidemiology
• 3
rd
or 4
th
decade
• M:F ~ 7:1
• 10-15 years to develop
• Frontal > ethmoid > maxillary > sphenoid
• Fronto-ethmoidal ~65%
• Maxillary ~ 20%
• Sphenoid ~1-8%
• Posterior ethmoid ~1-6%
• Uncommon locations: middle turbinate, pterygomaxillary space
Epidemiology
Epidemiology
• Rombaux et al (Belgium, 2000):
• 178 mucoceles
• Primitive mucoceles: 35%
• Post-traumatic: 2.1%
• Post-operative: 62.9%
• Incidence after FESS not known
Clinical Presentation
Clinical Presentation
• Slow expansion
• Patients asymptomatic for many years
• May take 10 years or more to become symptomatic
• Symptoms depend on location/type of mucocele and extent
of bony erosion

• 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

• Frontal swelling +/- infection/draining fistula
• Nasal obstruction and rhinorrea unusual
Fronto
Fronto
-
-
ethmoidal Mucocele
ethmoidal Mucocele
• Ocular:
• Proptosis (common)
• Periorbital pain
• Displacement of globe
downward and outward
direction
• Reduced ocular mobility
• Diplopia
Fronto
Fronto
-
-
ethmoidal Mucocele
ethmoidal Mucocele
• Neurologic:
• Destruction of posterior frontal sinus wall
• Decreased LOC
• Confusion
• Meningitis
• CSF leak
Maxillary
Maxillary

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

• Retro-orbital pain
• Neurologic:
• Decreased LOC
• Confusion
• Meningitis
• CSF leak
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Investigations
Investigations
• CT scan provides excellent anatomical information
• Findings:
• Completely opacified sinus cavity
• Thinned and expanded sinus walls
• Loss of normal scalloped margin
• Depression or erosion of supra-orbital ridge and extension of soft
frontal tissue mass across midline
Investigations
Investigations
• MRI scan:
• Allows differentiation of mucoceles from solid component of
neoplasms or meningoencephalocele
• Demarcates mucocels and soft-tissue structures in the event of
intracranial or intraorbital growth
• Findings:
• Signal intensity vary depending on state of hydration and age
• Majority show hyperintense T2 and hypointense T1
• Increased dehydration  T2 become hypointense and T1 become
hyperintense
Treatment
Treatment

• 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

• Mucoceles, pyoceles, cutaneous fistulae and CSF leaks, or
intracranial complications from fronto-ethmoidal sinuses
• Exposure for benign tumours of fronto-ethmoidal sinuses, anterior
skull base, or superior nasal cavity
External
External
Frontoethmoidectomy
Frontoethmoidectomy
• Technique (Lynch)
• Incision made near medial
orbital rim; avoid damage to
medial canthal ligament and
trochlea
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External
External
Frontoethmoidectomy
Frontoethmoidectomy
• Technique (Cont’d)
• Periosteum elevated to fronto-ethmoid
suture
• Anterior ethmoid artery divided
• Lamina papyracea removed and
ethmoidectomy performed
• Frontal sinus opened in medial part of
floor
• Diseased tissue within sinus is removed
• Large chute from frontal sinus through
ethmoid cavity into the nose
• +/- stent placement

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:

• Unilateral or bilateral anterior ehtmoidectomy
• Interfrontal septum and superior nasal septum and frontal recesses
connected
• High risk of cribriform plate damage:
• Anosmia
• CSF leak
• Meningitis
Osteoplastic
Osteoplastic
Flap
Flap
• 1894: described by Brieger
• Fat obliteration:
• First described in 1950 by Bergara
• Prevent recurrence
• Associated with varying degree of
necrosis and resorption
• Indications:
• Neoplasms
• Fractures
• Chronic frontal sinusitis associated
with orbital or intracranial
complications
Osteoplastic
Osteoplastic
Flap
Flap
• Incisions:
• Coronal approach
• Midline forehead approach

• 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

• Mucosa lining stripped and
drilling of cortical bone
performed
• Minimum 2 mm
required to eliminate all
mucosal elements
Osteoplastic
Osteoplastic
Flap
Flap
• Technique:
• Mucosa lining stripped and
drilling of cortical bone
performed
• Minimum 2 mm
required to eliminate all
mucosal elements
Osteoplastic
Osteoplastic
Flap
Flap
• Technique:
• Once frontal recess reached,
mucosa is inverted down
toward nasal cavity
• Fat harvested from lower left
quadrant of the abdomen
over rectus muscle used to
obliterate sinus cavity
• Frontal recess is plugged

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:

• Seroma
• Hematoma
• Abscess
• Cellulitis
• Intracranial:
• Dural tears
• Frontal lobe injury
• CSF leaks
• Meningitis
• Brain abscess
Osteoplastic
Osteoplastic
Flap
Flap
• Complications (Cont’d):
• Ocular:
• Extraocular muscle injury
• Globe injury
• Hemorrhage  retrobulbar hematoma  diplopia/blindness
• Infection:
• Fat graft
• Osteomyelitis of bone flap
Osteoplastic
Osteoplastic
Flap
Flap
• Complications (Cont’d):
• Nerve injury:
• Supraorbital nerves  forehead paresthesia, hypoesthesia or
anaesthesia

• 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:

• Short hospital stay
• No facial scarring
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Endoscopic
Endoscopic
Approach
Approach
• Contraindications (Rombaux et al, 2000)
• Absolute:
• Mucocele not accessible to endoscope
• Mucocele located in external part of frontal or maxillary sinus
• Cutaneous fistula
• Relative:
• Loss of anatomical landmarks
• Revision surgery for recurrence lateral to frontal recess after
previous external approach
• Frontal recess stenosis with hypertrophic bone occluding area
• Associated disease (ie. Malignancy, large benign tumour)
Endoscopic
Endoscopic
Approach
Approach
• Technique:
• Polyps or polypoid
mucosa cleared
from frontal recess
Endoscopic
Endoscopic
Approach
Approach

• 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

frontal sinus
preserved
• Provides source of
epithelialization
10
Endoscopic
Endoscopic
Approach
Approach
• Technique (Cont’d)
• Floor of frontal sinus anterior to outflow tract removed
• Mucocele identified, opened and drained
• Lining not curetted or removed
• +/- stent insertion
Endoscopic
Endoscopic
Approach
Approach
• Postoperative Care:
• Antibiotics and saline spray
• Irrigation of stent
• Removal of stent 6-12 weeks after surgery
Endoscopic
Endoscopic
Approach
Approach
• Results:
• Many studies show recurrence rates at or close to 0%
• Rombaux et al;Acta Oto-Rhino-Laryngologica Belg. 54:115-122,
2000

• 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:

• 9% endoscopic group
• 26% external or combined group
External vs.
External vs.
Endoscopic
Endoscopic
Approaches
Approaches
• Traditional teaching:
• Complete removal of mucocele lining
• Required external techniques
• Recent trend favouring endoscopic approach
• Marsupialization for large mucoceles controversial
• Long-term follow-up required
• Results of studies may not be final
• Follow-up in many series is short
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External vs.
External vs.
Endoscopic
Endoscopic
Approaches
Approaches
• “small, well-positioned mucoceles may be attempted first
endoscopically, but in the setting of massive mucoceles
with risk of imminent complications and instability of the
facial skeleton, the more conservative approach may be the
more aggressive open techniques”
• “endoscopic transnasal approach best choice for
intracranially extended mucoceles because it is the least

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

Case Presentation #2
Case Presentation #2
• 72 yo F
• Referred from ophthalmology
• Decreased vision of left eye
• Left retro-orbital pain
• No sinus symptoms
• Rhinoscopy: normal
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Case Presentation #2
Case Presentation #2
Case Presentation #2
Case Presentation #2
Case Presentation #2
Case Presentation #2
• Dx: sphenoethmoidal mucocele
• Treatment:
• Left functional endoscopic sinus surgery
• Uncinectomy
• Anterior ethmoidectomy
• Posterior ethmoidectomy  greenish fluid expelled and drained
Case Presentation #2
Case Presentation #2
• Treatment (Cont’d):
• Marsupialization of
posterior ethmoid cells
• Removal of anterior and
inferior walls
Case Presentation #2
Case Presentation #2

• 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

secretions
• Marsupialized
• Dehiscence of LP
Case Presentation #3
Case Presentation #3
• Discharged home
• Returned to ER with progressive headache, nausea,
vomiting and dehydration
• CT report:
• “area of calcification in planum sphenoidale. It is uncertain
whether this is related to the mucocele, or possibly represents an
underlying meningioma”
Case Presentation #3
Case Presentation #3
• Repeat CT scan
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Case Presentation #3
Case Presentation #3
• Repeat MRI
Case Presentation #3
Case Presentation #3
Case Presentation #3
Case Presentation #3
• Dx: Tuberculum sellae meningioma
• Involving:
• Pituitary gland
• Both cavernus sinuses
• Compression of left optic nerve
• Endocrinology: no endocrinopathy
• Ophthalmology: mild left visual field defect

• 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

• Orbital roof defect reconstructed
• Frontal recess plugged, sinus obliterated with fat and Tisseel
• Bone flap replaced
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Case Presentation #4
Case Presentation #4
• Post-op
• Accumulation of CSF under right forehead scalp
• No rhinorrhea
• Bed rest and aspiration of fluid
• Persistent leak  lumbar drain
• Resolution of CSF leak
• No infection
• Discharge home
• Follow-up
• Well with no recurrence
Summary
Summary
• Mucoceles most common lesion causing expansion of
paranasal sinuses
• Long asymptomatic progress
• When symptomatic, usually present with ocular symptoms
+/- neurologic symptoms depending on location of
expansion
• Fronto-ethmoidal mucoceles most common
• Caused by sinus obstruction secondary to chronic
infection, surgery or trauma
Summary
Summary
• Treatment is surgical

• 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