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Flashcards in Middle Ear Deck (147):
1

What is the incidence of malleus ankylosis during primary surgery for otosclerosis

0.4- 1.6%.

2

What is the incidence of tympanic membrane perforation 6 months after pressure equalizing tube extrusion

0.5-2%.

3

What is the incidence of facial nerve paralysis in patients with chronic otitis media and cholesteatoma

1%.

4

What are the expected residual hearing levels after PORP and TORP

15 dB conductive hearing loss PORP; 25 dB conductive hearing loss TORP.

5

What % of congenital cholesteatomas are bilateral

3%.

6

In patients with chronic otitis media but not cholesteatoma, what level of hearing loss is associated with ossicular chain disruption or fixation

30 dB or more.

7

What is the rate of extrusion of middle ear prostheses

4- 7%.

8

What is the incidence of malleus ankylosis during revision surgery for otosclerosis

4.5- 13.5%.

9

What is the mean age of presentation for congenital cholesteatoma

4.5 years.

10

What % patients have erosion of the scutum with cholesteatoma

42%.

11

What % of cholesteatomas are complicated by a labyrinthine fistula

5 - I O%.

12

What is the overall success (accounting for extrusion, HL, and graft take) at 4 months using TORP or PORP

58% TORP; 64% PORP.

13

What % of cases of otosclerosis are bilateral

85%.

14

Why is stapedectomy dangerous in patients with Meniere's disease

A dilated saccule may sit immediately beneath the footplate and be injured upon entry into the vestibule.

15

How do the surgical findings differ during removal of congenital cholesteatoma from removal of cholesteatoma associated with chronic suppurative otitis media

Absence of inflammatory changes/adhesions and easier removal with potential for complete preservation of the middle ear mucosa.

16

What are the indications for using plastic sheeting in middle ear surgery

Absence of mucosa on the promontory, in most of the middle ear, or in the middle ear cleft (except in the eustachian tube).

17

What are the indications for simple mastoidectomy

Acute coalescent mastoiditis with complications or acute mastoiditis that does not resolve after appropriate antibiotic therapy and myringotomy.

18

How should an extruded prosthesis be managed

Allow spontaneous extrusion; TM may heal and make a spontaneous connection.

19

What are the 2 parts of a cholesteatoma

Amorphous center surrounded by keratinized squamous epithelium.

20

What are the complications of lateral tympanoplasty

Anterior blunting, lateralization, epithelial pearls, canal stenosis.

21

What are the indications for performing a lateral tympanoplasty

Anterior or large perforations, revision tympanoplasty, or if the anterior canal wall is in the way.

22

What is the most commonly involved site of otosclerosis in the temporal bone

Anterior to the oval window at the fissula ante fenestrum.

23

What is the management of injury to the sigmoid sinus during mastoidectomy

Apply gentle pressure, place a Surgicel or Gelfoam patch, and continue with surgery.

24

In a child with spontaneous CSF leak to the middle ear, where is the leak most commonly located

Around the stapes footplate.

25

What are the options for surgical management of the chronically draining mastoid cavity

Autologous cultured epithelial graft (from buccal mucosa), large meatoplasty, revision mastoidectomy, reconstruction of canal wall with an aerated cavity, mastoid cavity obliteration, and mastoid/middle ear obliteration.

26

What is the inheritance pattern of otosclerosis

Autosomal dominant with incomplete penetrance (only 25 - 40% of carriers express the phenotype).

27

What does the "Blue Mantles of Manasse" refer to

Basophilic appearance on hematoxylin and eosin staining of bone in the active stage of otosclerosis.

28

What are the 2 types of tympanic membrane perforations

Central and marginal.

29

What are the boundaries of the facial recess

Chorda tympani laterally, upper mastoid segment of VII medially, bone of fossa incudis superiorly.

30

What factors predispose one to complications from OM

Chronic infection, history of mastoid surgery, cholesteatoma, diabetes, • • tmmunocompromtse.

31

What are the 2 types of cholesteatomas

Congenital and acquired.

32

What are the 3 principle theories regarding the etiology of cholesteatoma

Congenital theory (von Remak, 1854 and Virchow, 1855)~ metaplasia theory (Trolscht, 1873); migration theory (Habermann, 1888).

33

What is the most common cause of malleus ankylosis

Congenital.

34

Should a cholesteatoma be removed over a fistula

Controversial, in that leaving a piece of matrix to seal the fistula increases the risk of recurrent cholesteatoma, while completely removing the matrix and exposing the fistula increases the risk of hearing loss and vertigo.

35

What is a radical mastoidectomy

Conversion of the mastoid, antrum, and middle ear into a common cavity, with removal of the tympanic membrane, malleus, incus, chorda tympani, and mucoperiosteum.

36

What is a modified radical mastoidectomy

Conversion of the mastoid, epitympanum, and external auditory canal into a common cavity by removal of the posterior and superior external bony canal walls.

37

What is the most common complaint of patients with an epidural abscess/granulation tissue

Deep, constant pain in the temporal area that is very steroid responsive.

38

What are the radiographic findings of sigmoid sinus thrombosis

Delta sign on CT scan with contrast and central nonenhancement of the sigmoid sinus; decreased intraluminal signal on MRI with gadolinium.

39

What is the typical route of spread of cholesteatomas originating in anterior mesotympanum

Descend to the pouch of Von Troeltch, and may involve the stapes, sinus tympani, or facial recess.

40

In a patient with a cholesteatoma, what factors make presence of a fistula highly unlikely

Disease

41

What is a congenital cholesteatoma

Embryonal inclusion of undifferentiated squamous epithelium in the middle ear behind an intact TM, usually with no history of otitis media.

42

What are the intracranial complications of otitis media (OM)

Epidural abscess/granulation tissue, sigmoid sinus thrombosis, meningitis, brain abscess, subdural abscess.

43

What are the symptoms and signs of a poststapedectomy perilymph fistula

Episodic vertigo, especially with exertion, sensorineural hearing loss, loss of speech discrimination, and nystagmus with changes of air pressure on the TM.

44

What factors contribute to extrusion

Eustachian tube dysfunction (70%), graft failure, cartilage resorption.

45

What are the advantages of lateral tympanoplasty

Excellent exposure, high graft take rate (95%), most versatile approach.

46

What is the significance of pain in a patient with cholesteatoma or chronic otitis media

Expanding mass or empyema in the antrum.

47

How is this treated

Expedient elimination of infection.

48

What are the indications for staging a tympanoplasty without mastoidectomy

Extensive mucous membrane destruction, stapes fixation.

49

What are the 5 primary causes of conductive hearing loss after stapedectomy

Failure to recognize obliterative otosclerosis of the round window; displacement of the prosthesis after head trauma or large changes in middle ear pressure; necrosis of the long process of the incus; migration of the prosthesis in the oval window; and adhesions.

50

T/F: In cases of malleus fixation, mobilization of the malleus usually results in lasting hearing improvement

False.

51

What features on history distinguish FAO from profound SNHL

Family history of otosclerosis; progressive hearing loss usually of long duration; history of hearing aid use that is no longer beneficial or present use of a hearing aid with benefit beyond that which would be expected for the severity of the hearing loss; paracusis; and previous audiograms indicating an air-bone gap.

52

What are the terms used to describe involvement of the oval window and cochlea

Fenestral otosclerosis and retrofenestral otosclerosis, respectively.

53

What is the most common tumor of the middle ear

G lorn us tympanicum.

54

What is the prognosis after such an injury

Good if immediately recognized and treated.

55

What are the most common pathogens cultured from otorrhea after tympanotomy tubes in children younger than 3

Haemophilus influenza and Diplococcus pneumoniae.

56

What are the three most common organisms causing meningitis secondary to OM

Haemophilus influenzae, type 8, Streptococcus pneumoniae, Neisseria meningitides.

57

What are the disadvantages of the CWD procedure in the management of cholesteatoma

Healing is slower, indefinite periodic cleaning and dry ear precautions are required, and hearing aids are more difficult to fit in the meatus.

58

What are the advantages of using porous polyethylene prostheses over fitted autograft ossicles

Hearing is more stable, decreased incidence of residual and recurrent cholesteatoma.

59

What is the significance of a white versus a blue floating footplate

Hearing success is much less in the presence of a white floating footplate (52°/o) versus a blue floating footplate (97%).

60

What can cause persistent cavity discharge after CWD procedures

High facial ridge, particularly large cavity, open middle ear space, inadequate meatal opening, poor postoperative care leading to infection.

61

What is the significance of sensorineural hearing loss after stapedectomy

If no tissue graft was used, 50% of SNHL will be due to fistulas and should be revised.

62

Revision stapedectomy is performed. What should be done with the original prosthesis

If possible, it should be left in place, and a second fenestra and prosthesis should be placed.

63

When is a CT scan obtained

If signs of progression arise while on IV antibiotics or if the patient presents with possible intracranial complications.

64

When is mastoidectomy indicated

If the CT scan shows coalescent mastoiditis and/or intracranial involvement.

65

How much more bone conduction will dental conduction provide than mastoid conduction

II dB.

66

What is the management of intraoperative violation of the labyrinth

Immediate application of a Gel foam patch or other tissue seal (other than fat).

67

When is mastoid and middle ear obliteration most appropriate

In a dead ear, without cholesteatoma.

68

How does the hearing impairment from malleus ankylosis differ from that of otosclerosis

In patients with malleus ankylosis, hearing impairment is mostly unilateral (78°/o); the air-bone gap is smaller (majority less than 20 dB); sensorineural hearing loss is more frequent, particularly at 4 kHz; acoustic reflex is more likely to be present on the contralateral ear and absent on the impaired ear.

69

When is stapedectomy contraindicated

In young children until it has been demonstrated that they are not prone to otitis media, in the presence of active middle or external ear disease or active URI, tympanic membrane perforation, Meniere's disease.

70

Which portions of the ossicular chain are always removed in CWO procedures

Incus and head of the malleus.

71

Which ossicle is most commonly involved in patients with cholesteatoma

Incus.

72

What is the significance of the ability to hear a tuning fork placed on the teeth

Indicates that cochlear reserve is present and surgery may be beneficial.

73

What are the histopathologic findings of patients with FAO

Invasion of otosclerotic foci into the cochlear endosteum and the stapes footplate.

74

During stapedectomy, the entire stapes footplate falls into the vestibule. What should be done

It should be left in the vestibule, as attempts to retrieve it are more likely to cause damage than leaving the footplate where it is.

75

Where does this most often occur

Lateral semicircular canal (75% ).

76

What is the most common location for iatrogenic labyrinthine fistula formation during mastoidectomy

Lateral semicircular canal.

77

What are the disadvantages of the canal wall up (CWU) approach

Limited exposure of the anterior epitympanum, sinus tympani, and facial recess.

78

Which areas of the middle ear are most difficult to see during mastoidectomy

lnfrapyramidal and tympanic recesses.

79

What are the disadvantages of lateral tympanoplasty

Longer healing time, potential for anterior blunting or lateral healing, technically more difficult.

80

What are the 2 most important principles of CWD procedures

Lowering the posterior canal wall to create a round cavity and creating a large meatus.

81

What is the single most important factor affecting hearing results after CWO tympanomastoid surgery

Maintenance of a pneumatized space juxtaposed to the round window.

82

Which of these is associated with cholesteatoma

Marginal.

83

What is obliterative otosclerosis

Margins of the footplate cannot be seen or removed.

84

What virus is thought to play a role in the etiology of otosclerosis

Measles.

85

Which of these layers does otosclerosis involve

Middle endochondral layer.

86

If the CWU procedure is chosen, what are the indications for a 2"d look

Missing middle ear mucosa or extensive cholesteatoma.

87

What congenital ear malformation is most commonly associated with perilymph fistula in children

Mondini deformity.

88

What is the significance of hearing loss in the absence of middle ear effusion in patients with congenital cholesteatoma

Most lesions begin anterosuperiorly and extend posteriorly with growth. Hearing loss indicates posterior extension with involvement of the stapes superstructure and/or the lenticular process of the incus.

89

What genetic mutation has been implicated as a possible cause of otosclerosis

Mutation of the COLlA I gene on chromosome 17q.

90

What are the potential problems with a type IV tympanoplasty

Narrowing of the middle ear space and graft lateralization.

91

What is the advantage of using a laser for stapedectomy

No-touch technique with less risk of a floating footplate.

92

What are the indications for 2"d look surgery after removal of a congenital cholesteatoma

Obvious recurrent disease, unexplained deterioration in hearing, concern about the adequacy of the initial surgery or disease found to extend into the antrum or mastoid.

93

What type of cholesteatoma is most frequently found in the facial recess

One associated with a perforation below the posterior malleolar fold.

94

According to Sheehy, in which situations is the canal wall down (CWD) approach most appropriate

Only-hearing ear, very contracted mastoid, mastoid with a labyrinthine fistula, or presence of canal wall erosion due to disease.

95

What is the most common cause of perilymph fistula

Otologic surgery (stapedectomy).

96

How is far-advanced otosclerosis (FAO) defined

Otosclerosis with an air conduction threshold greater than 85 dB and a bone conduction threshold not measurable.

97

What are the three layers of the otic capsule

Outer periosteal layer, inner periosteal layer (endosteum) and the middle endochondral layer.

98

Where is dehiscence of the bony facial canal most common

Over the oval window.

99

What factor strongly correlates with survival and long term neurologic deficits in patients with a brain abscess

Patient's level of consciousness at the time of diagnosis.

100

What features on physical exam distinguish FAO from profound SNHL

Patients with F AO more likely will have a soft voice with better quality than expected for the degree of hearing loss and the ability to hear a 512 Hz tuning fork placed on the teeth, dentures, or gums.

101

What is the most common postoperative complication of pressure equalizing tube insertion

Persistent otorrhea.

102

What vessels can be injured in the middle ear during tympanoplasty

Persistent stapedial artery, superficial petrosal branch of the middle meningeal artery, high-riding jugular vein, and anomalous carotid artery.

103

What are the most common reasons for mastoid surgery failure without recurrent cholesteatoma

Persistent suppurative disease in unexenterated air cells (most commonly at the sinodural angle and along the tegmen) and technical factors such as high facial ridge or meatal stenosis.

104

Other than the middle ear, where else may congenital cholesteatomas arise

Petrous apex, cerebellopontine angle, mastoid, external auditory canal.

105

What are the most common signs and symptoms of sigmoid sinus thrombosis

Picket fence fever, cannon ball infiltrates on CXR, torticollis, jugular foramen syndrome, otitic hydrocephalus.

106

What technique is employed during ossiculoplasty to decrease the risk of prosthesis extrusion

Placement of cartilage between the prosthesis and the tympanic membrane.

107

What techniques can be used to accomplish this

Placement of the fascia graft such that it does not obliterate the space between the eustachian tube orifice and the round window; placement of silastic crescent in the hypotympanum.

108

Unbeknownst to the surgeon, the dura is torn during mastoidectomy, and postoperatively, the patient develops a severe headache, followed by hemiplegia and coma. What has likely happened

Pneumocephalus~ torn dura can create a ball valve-like effect and trap air from the middle ear. Influx of air may occur during Valsalva or as a result of high intracranial negative pressure due to the rapid escape of CSF through the tear.

109

What is thought to cause congenital malleus ankylosis

Poor development of the epitympanic space leaves the head of the incus and malleus in close contact with the tegmen; a bony bridge can result between the epitympanum and the head of the malleus.

110

In patients with bilateral otosclerosis, which ear should be operated on first

Poorer hearing ear.

111

What are the most common sites of origin of primary acquired cholesteatomas

Posterior epitympanum, posterior mesotympanum, and anterior epitympanum (in descending order of frequency).

112

What conditions accelerate hearing loss in patients with otosclerosis

Pregnancy, estrogen replacement.

113

What are the 2 types of acquired cholesteatomas

Primary and secondary.

114

What is the difference between a primary and a secondary cholesteatoma

Primary usually occurs in the attic at Shrapnell's membrane and starts as a retraction pocket; secondary is associated with chronic middle ear infection and TM perforations.

115

What are the early signs and symptoms of intracranial infection

Prolonged suppurative OM, fetid discharge and persistent pain despite adequate treatment, bony destruction of inner cortex of mastoid on CT scan.

116

What is a "perilymph gusher"

Rapid release of perilymph after stapes footplate fenestration due to pressure and fluid from the CSF compartment venting through the inner ear.

117

What are the most common reasons for recurrent conductive hearing loss after tympanoplasty

Recurrent perforation, blunting of the angle between the tympanic membrane and the external auditory canal, graft lateralization, graft thickening and adhesions, severe graft atelectasis.

118

What is "Schwartze's sign"

Reddish hue on the promontory associated with otosclerosis.

119

What is the benefit of amputating the mastoid tip

Reduces cavity size and eliminates a dependent cavity area that is not visible.

120

What is the optimal treatment of malleus fixation

Removal of the head of the malleus and interposition of the incus between the manubrium and the stapes head.

121

What is the management of injury to the dura with CSF leak during mastoidectomy

Repair with temporalis fascia held in place with sutures or packing and continue with surgery; small tears can be managed with a Surgicel or Gelfoam patch.

122

In patients with bilateral otosclerosis and equal hearing loss, which ear should be operated on

Right-handed surgeon should work on the left ear (or patient preference).

123

What is the most common cause of failure using a fitted ossicle for middle ear reconstruction

Separation of the ossicle from the stapes.

124

What other techniques can help improve hearing results

Shielding the round window to increase the difference in sound pressure between the oval and round windows~ placing the graft directly atop the head of the stapes when the suprastructure is present; using a TORP or placing the graft directly on the stapes footplate when the suprastructure is not present (type IV tympanoplasty).

125

If a CWO procedure is used to treat a posterior-superior retraction cholesteatoma, what would be the most likely site of residual cholesteatoma

Sinus tympani.

126

What is the medical treatment for otosclerosis

Sodium fluoride, vitamin D.

127

What are the indications for using a TORP when the stapes suprastructure is present

Stapes tilted towards the promontory, partial arch necrosis, and unusually deep oval window niche where a PORP might contact the fallopian canal and/or promontory.

128

What are the most common pathogens cultured from otorrhea after tympanotomy tubes in children older than 3

Staphylococcus aureus and Pseudomonas aeruginosa.

129

What is the typical route of spread of cholesteatomas originating in the posterior epitympanum

Starting from Prussak's space, penetrate posteriorly to the superior incudal space lateral to the body of the incus and progress to the aditus and the antrum.

130

What are the three most common organisms of OM that result in intracranial infections

Streptococcus faecalis. Proteus, Bacteroides fragilis.

131

What are the extracranial complications of OM

Subperiosteal (Bezold's) abscess, petrositis, labyrinthitis, facial nerve paralysis.

132

What is the most common complication of acute mastoiditis

Subperiosteal abscess.

133

What is the significance of Tullio's phenomenon after stapedectomy

Suggests that the prosthesis is too long and impinging on the saccule.

134

What is the Paiva flap

Technique used for mastoid obliteration where the soft tissue off the back of the ear is swung into the mastoid.

135

How is the round window evaluated for normal movement

The membrane is not readily visible, so a drop of saline is placed in the niche and movement is seen as a change in light reflection on the meniscus when the prosthesis is palpated.

136

Why is it important to saucerize the cavity margins

The soft tissues and auricle will assume a more medial position during healing, resulting in a smaller cavity.

137

In patients where one ear has previously been operated on and hearing loss is equal bilaterally, which ear should be operated on

The unoperated ear.

138

At what age does otosclerosis peak in incidence

Third decade.

139

What is the most common etiology of spontaneous CSF leak to the middle ear in adults

Through a defect in the mastoid tegmen secondary to a meningoencephalocele.

140

What is the purpose of the plastic sheeting in these conditions

To prevent adhesions from forming and to allow mucosa to grow over denuded areas.

141

T/F: Postoperative hearing improvement and reperforation rates are similar for medial and lateral tympanoplasty

True.

142

T/F: The modified radical mastoidectomy does not involve a tympanoplasty

True.

143

T/F: The mastoid bones of patients with congenital cholesteatoma are most often well-aerated

True.

144

T/F: Histologically, the bony structures are normal, without evidence of otosclerosis, in cases of malleus ankylosis

True.

145

What is the treatment for uncomplicated acute mastoiditis

Tympanocentesis for culture and IV antibiotics.

146

Is the acoustic reflex present in patients with otosclerosis

Usually it is absent bilaterally, even if the disease is unilateral.

147

What is Tullio's phenomenon

Vertigo with loud noise.