Tumors of the Lateral Skull Base and Cerebellopontine Angle A

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Transcript Tumors of the Lateral Skull Base and Cerebellopontine Angle A

Chronic Otitis Media (COM) with and without
Cholesteatoma
Pathophysiology, Diagnosis, and Management.
Abraham Jacob, MD
Otolaryngology – Head and Neck Surgery
Otology, Neurotology, and Cranial Base Surgery
The Ohio State University
Images used in this lecture were obtained from the presenter’s collection, various
textbooks and internet websites. Their use is for educational purposes only.
Objectives
• To define the normal anatomy and physiology of the ear, Eustachian
tube, and lateral skull base.
• To understand the role of Eustachian tube dysfunction in the
development of chronic ear disease.
• To define chronic otitis media (COM) with and without
cholesteatoma.
• To define the various types of cholesteatoma and how they develop.
• To understand the clinical presentation and diagnostic evaluation of
COM.
• To provide an overview of the surgical management of COM.
Anatomy of the Ear and Temporal Bone
The Ear – Anatomic Overview
The Temporal Bone
Made up of the squamous bone, the petrous bone, the tympanic bone, and the
styloid process.
The mastoid is a part of the petrous bone.
The Middle Ear
The Eustachian Tube
The Eustachian Tube
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Connection between middle ear (ME) & nasopharynx (NP)
Medial 2/3 fibro-cartilage; lateral 1/3 bony
Equalizes ME pressure with atmospheric pressure
Allows air into the middle ear and mastoid to spur air cell
development
Lined with respiratory epithelium
– Mucociliary clearance towards the NP – drains fluid from ME
Usually closed to prevent reflux of NP contents into ME
13 mm @ birth; 36 mm in adulthood
More horizontal at birth; elongates and descends over time
Eustachian Tube
Embryology
• ET and middle ear develop from the first pharyngeal pouch
(endoderm)
• The external ear canal develops from the first branchial cleft
(ectoderm)
• The ossicles develop from the 1st and 2nd branchial arches
• The interface between the first pharyngeal pouch and the first
branchial cleft is the tympanic membrane
Eustachian Tube Dysfunction
• Abnormal cranial base anatomy
– Bony anatomy
– Abnormal musculature
•Tensor veli palatini and/or levator veli palatini
• Inflammation/edema
• Physical obstruction
• Usually “too closed” but can also be “too open”
(patulous Eustachian tube)
Eustachian Tube Dysfunction
• ETD is central to the development of otitis media
– Acute otitis media
– Recurrent acute otitis media (ROM)
– Otitis media with effusion (chronic non-suppurative otitis
media)
– Middle ear atelectasis
– Chronic suppurative otitis media
•Without cholesteatoma
•With cholesteatoma
Middle Ear Disease
Acute Otitis Media (AOM)
• The diagnosis of AOM requires:
– History of acute onset signs and symptoms
– Presence of middle ear effusion (MEE)
– Signs and symptoms of middle ear inflammation
The presence of MEE is indicated by:
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A bulging tympanic membrane
Limited or absent tympanic membrane mobility
Air-fluid level behind the TM
Otorrhea (drainage from the ear)
Signs of middle ear inflammation include:
- Erythema of the tympanic membrane
- Otalgia (ear pain)
Acute Otitis Media (AOM)
Etiology of Acute Otitis Media
• S. pneumoniae
• H. influenzae
• M. catarrhalis
• S. pyogenes (gr. A)
• S. aureus
• No growth
25%
20-25%
10-20%
2%
1%
up to 35%
Recurrent Acute Otitis Media
• Multiple bouts of acute otitis media with
complete resolution between episodes
• 4 episodes in 6 months or 6 episodes in 1 year
is an indication for tympanostomy tube
placement
Otitis Media with Effusion
(Chronic non-suppurative Otitis Media)
• Middle ear filled with serous or mucoid fluid
• No purulence
• Often present after acute otitis media is treated
appropriately with antibiotics
• Most will clear within 3 months
Etiology of OME
• 50% sterile to culture
– Molecular techniques find bacterial
products
• When culture +, similar to AOM
Medical Treatment of OME
• Observation – many European countries wait 6-9
months prior to placement of ear tubes
• Antibiotics
– Meta-analysis shows beneficial short-term resolution of
OME
– Unclear long-term impact
• Audiogram at 3 months with persistent effusion to
determine impact on hearing
Tympanostomy Tubes
• In the US, chronic OME >3mos with hearing loss and/or
speech delay is an indication for tympanostomy tube placement
• Not just there to “drain fluid”
• Bypass Eustachian tube to ventilate middle ear
Middle Ear Atelectasis
• Lack of middle ear ventilation results in negative pressure
within the tympanic cavity
• The ear drum retracts onto structures within the middle
ear
• The result of long standing Eustachian tube dysfunction
• The drum loses structural integrity and becomes flaccid
• Contact between the drum and the incus or stapes can
cause bone erosion at the IS joint
• Can sometimes be treated with tympanostomy tubes
Middle Ear Atelectasis
Middle Ear Atelectasis
• Patient is at risk for cholesteatoma due to skin
accumulation within retraction pockets
• Drum contact with the incus and/or stapes cause
erosion of the incudostapedial (IS) joint
• TM is flaccid and non-vibratory – affects hearing
• Early atelectasis may be treatable with tympanostomy
tubes
• Severe atelectasis requires removal of the flaccid ear
drum and replacement using cartilage (cartilage
tympanoplasty)
– This adds rigidity to the drum at the expense of vibratory
capacity
Chronic suppurative otitis media with
and without cholesteatoma
Chronic suppurative otitis media without
cholesteatoma
• Chronic infection of the middle ear with a non-healing
perforation of the tympanic membrane
• Otorrhea (ear drainage) for 6-12 weeks
• Middle ear mucosa becomes edematous, polypoid, or
ulcerated
• The tympanic cavity usually contains granulation tissue
• Most common infecting organisms are Pseudomonas
aeruginosa, Staphylococcus aureus, Proteus species,
Klebsiella pneumoniae, and diphteroids
• Annual incidence approximately 40 cases/100,000
population
Chronic suppurative otitis media without
cholesteatoma
• Patients present with hearing loss and otorrhea
• Pain, vertigo, fevers, facial nerve palsy, mental status
changes or fetid drainage signify impending intratemporal or intra-cranial complications
Near Total TM Perforation
Cholesteatoma
Cholesteatoma
• Cholesteatomas are epidermal inclusion cysts of the
middle ear and/or mastoid with a squamous epithelial
lining
• Contain keratin and desquamated epithelium
• Term “cholesteatoma” coined by Johannes Muller in
1838
• Misnomer because the cysts don’t contain cholesterol
• Can be congenital or acquired
• Natural history is progressive growth with erosion of
surrounding bone due to pressure effects and
osteoclast activation
Cholesteatoma
Cholesteatoma
• Annual incidence is unknown
• In 1978, there were 4.2 hospital discharges per
100,000 with cholesteatoma
(Ruben RJ: The disease in society: evaluation of chronic otitis media in general and cholesteatoma in
particular. In Sadé J, editor: Cholesteatoma and mastoid surgery, Amsterdam, 1982, Kugler Publishing)
• Harker and coworkers estimated the incidence
at 6/100,000
(Harker LA: Cholesteatoma: an incidence study. In McCabe BF, Sadé J, Abramson M, editors:
Cholesteatoma: first international conference, Birmingham, Alabama, 1977, Aesculapius Publishing)
• Tos and colleagues found 3/100,000 in children
and 12.6 per 100,000 in adults
(Tos M: Incidence, etiology and pathogenesis of cholesteatoma in children, Ann Otol Rhinol Laryngol
40:110, 1988)
Congenital cholesteatoma
– Epidermal inclusion cysts usually present in the anterior
superior quadrant of the middle ear near the Eustachian
tube orifice
– Michaels found epidermoid formation in 37 of 68 temporal
bones of fetuses at 10 to 33 weeks' gestation.
(Michaels L: An epidermoid formation in the developing middle ear; possible source of cholesteatoma,
Otolaryngol 15:169, 1986)
– Diagnosed as a pearly white mass behind an intact tympanic
membrane in a child who does not have a history of chronic
ear disease
Acquired
Cholesteatoma
Pathogenesis
• Invagination
• Basal cell hyperplasia
• Migration (through a
perforation)
• Squamous metaplasia
Primary acquired cholesteatoma
– Retraction pocket cholesteatoma usually within the
pars flaccida or posterior superior tympanic
membrane (invagination Theory)
– Secondary to ETD
– Keratin debris collects within a retraction pocket
Normal TM
Mucoid effusion and primary
acquired cholesteatoma
Mesotympanic
cholesteatoma
Primary acquired cholesteatoma
Secondary Acquired Cholesteatoma
• Migration Theory – most accepted
• Originates from a tympanic membrane perforation
• As the edges of the TM try to heal, the squamous
epithelium migrates into the middle ear
COM with and without cholesteatoma
Diagnosis
COM with and without cholesteatoma
Diagnosis
• History, physical examination, high resolution
CT scan of the temporal bone
Axial Section
Coronal Section
Cholesteatoma Imaging
Cholesteatoma Imaging
COM with and without Cholesteatoma
Treatment
Chronic suppurative otitis media
without cholesteatoma
• Ototopical antibiotics
• Surgical repair of the TM perforation
• Repair of the ossicular chain if necessary
Ototopical Medications
• Antibiotic only otic drops
Floxin (ofloxacin)
• Antibiotic with steroid otic drops
Ciprodex (ciprofloxin and dexamethasone)
Cipro HC (ciprofloxin and hydrocortisone)
Cortisporin (neomycin, polymyxin, and hydrocortisone)
• Ophthalmic antibiotic preparations
Tobradex (tobramycin and dexamethasone)
The concentration of antibiotic in ototopical drops is 100-1000x
greater than what can be achieved systemically.
Tympanoplasty
• Paper patch myringoplasty
• Fat myringoplasty
• Underlay tympanoplasty (medial graft technique)
Underlay Tympanoplasty
Ossicular Chain Reconstruction
Chronic suppurative otitis media with
cholesteatoma
• Ototopical antibiotics
• Surgical repair of the TM perforation
• Repair of the ossicular chain if necessary
• Often requires mastoidectomy
Mastoidectomy
• Intact (bony ear) canal wall mastoidectomy
• Canal wall down mastoidectomy
– Radical Mastoidectomy
– Modified Radical Mastoidectomy
Mastoidectomy
Tympanoplasty with mastoidectomy and
hydroxyapatite bone cement ossicular
reconstruction
COM with and without Cholesteatoma
Complications
Complications of Otitis Media
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Acute mastoiditis
Sub-periosteal abscess
Cholesteatoma
Labyrinthitis
Facial paralysis
Meningitis
Epidural/subdural
abscess
• Brain abscess
• Sigmoid sinus
thrombosis
• Otitic Hydrocephalus
Complications of Otitis Media
• Due to antibiotics, the incidence of
complications has greatly declined.
• Complications are usually associated with some
degree of bone destruction, granulation tissue
formation, or the presence of a cholesteatoma.
• Complications arise most commonly by
infection spreading by direct extension from the
middle ear or mastoid cavity to adjacent
structures.
Acute mastoiditis with sub-periosteal abscess
Brain
Abscess
Complications of Otitis Media
• Patients appear more ill than expected
– fever, new onset vertigo, sensorineural hearing loss, fetid
drainage, facial nerve weakness, proptotic ear
– lethargy and mental status changes
• CT and MRI are indicated
– CT is superior for evaluating the bony details of the middle
ear and mastoid space
– MRI is more sensitive for diagnosing suspected intracranial
complications.
• Broad spectrum antibiotics and surgery are required
Summary
• Eustachian tube dysfunction is central to the
development of ear disease
• Chronic otitis media without cholesteatoma is defined
as prolonged otorrhea thru a non-healing TM
perforation
• Cholesteatomas are bone destructive epithelial cysts
that require surgical removal
• The temporal bone is a complex anatomic region with
close proximity to a variety of critical structures. These
structures are at risk during both acute and chronic
otitis media