Jane

L. Weissman,

MD

Barry

E. Hirsch,

MD

Kenny

Chan,

MD

#{149} Ellen

K. Tabor,

Head Hugh

D. Curtin,

rects

Temporomandibular of an acute

effusion in bone dito the nasopharynx and

a well-pneumatized

temporal

attention

was

a central

perforation

membrane.

small

amount

mandibular joint allowed herniation of the contents of the joint posteromedially, where they obstructed the middle ear entrance of the eustachian tube, the protympanum. This is, to the authors’ knowledge, a previously unreported

(iothalamate Mallinckrodt, mography

middle

ear and

Axial

mas-

toid effusion. terms:

temporomandibulan,

Radiology

T

Joints,

1991;

fossa

was

244.78

was

of the

partially

forms

the

external

of the

glenoid

anterior

wall

auditory

canal.

of the More

niation of the mandibular associated soft tissues into

condyle or the anterior

middle ear can occur. We encountered two patients in whom this “herniation” blocked the middle ear entrance to the eustachian

tube

and

drainage

thus

interfered

of the middle

anterior

CASE

Both

ears

antibiotics

otoscopic

strated

the

normal.

treated

with

steroids.

Ten

unchanged

demonof

and clean ear. The per-

sistence of fluid in the middle ear despite the perforation of the tympanic

15-year-old

(von

girl with

for 2 months. that

were

that

She had

referable

neurofibroma

At otoscopic

was

dis-

no

to the

the

Departments

H.D.C.)

and

K.C.), the University

of Radiology

Otolaryngology

of Pittsburgh

(.J.L.W.,

School

of

230 Lothrop St, Pittsburgh, PA 15213. January 16, 1991; revision requested 20; revision received March 6; adMarch 8. Address reprint requests to

cepted H.D.C. © RSNA,

opened

her mouth.

clear.

axial

bones

wall

dehiscent plastic

the

CT images

through

that

the

of the left glenoid and

ear was

contrast-enhanced

revealed the

left

(Fig 4). The mandibular

small

condyle,

the

postero-

fossa

mandible

was

was

and along

dyswith

some soft tissue from the TM joint, protruded into the region of the hypotympanum and anterior mesotympanum. middle

developed

ear

and

and

clear.

mastoid

were

Postoperatively,

a

bouts

of otitis

disease At CT,

was high

to the orifice in the nasopharynx. The eustachian tube arises in the protympanum (anterior mesotympanum). The posterior 10-14 mm of the adult eustachian

which

patient

The middle

Preoperative

(Conray)

The 1991

face.

a variable

when

This with

anywhere along its course, origin in the mesotympanum

tube

well

petrous ally

is the

is completely

tilaginous.

decreased

patient

suggests that chronic ear not present in childhood.

sisted

but

suspicion.

the

of recurrent

The eustachian

malformed

(B.E.H.,

left

in

media (otomastoiditis), usually in childhood (2). There is wide variability in normal aeration (3). A well-developed mastoid

bulge in the contour of the anterior wall of the external auditory canal was seen; this bulge was most prominent when the patient closed her mouth and pen-

medial From

of the

examination,

as be-

ear was

well-developed mastoid, that is, a mastoid with many air cells that extend beyond the mastoid antrum. An underpneumatized, sclerotic mastoid is

obstructed from the

neu-

Recklinghausen

same

attenuation by the well-developed mastoid and the middle ear directs attention to the eustachian tube. The eustachian tube may be functionally or physically

membrane suggested ongoing eustachian tube dysfunction. However, the patient refused to undergo a radical mastoidectomy. 2.-A

with

true

suggestive

topical

perforation

be regarded

is especially

months

examination

the

the middle

DISCUSSION

should

at the

the left tympanic membrane mucoid fluid in the middle

facial

February

was

were and

later,

plexiform

woman otorrhea

left ear but admitted having experienced facial trauma in a motor vehicle accident many years earlier. Otoscopic examination revealed otitis externa on the right. On the left, however, there

Medicine, Received

with

mesotympanum

rofibromatosis

REPORTS

51-year-old of right-side

persisted

complaints

E.K.T.,

tissue

ease) was admitted for orthognathic surgery and debulking of an extensive

Case 1.-A seen because

I

2). Soft

8) was

and

The appearance of an acute middle ear effusion in an older child or adult

entrance to the eustachian tube (Fig 3). The left middle ear and mastoid air cells contained fluid on soft tissue (Fig 1). The

Case

ear and

mastoid.

had

(Fig

(Fig

fore surgery, again clean.

and

of the glenoid

similar to that of fat hernithe TM joint into the region

nasopharynx

medially, the posterior wall of the glenoid actually makes up a portion of the anterior wall of the middle ear. Because the glenoid fossa, which separates the external auditory canal and the middle ear from the temporomandibular (TM) joint, may be thin on dehiscent (1), her-

with

Radiology

the patient was placed in temporary intermaxillary fixation. CT performed after surgery showed that the appearance of the TM joints was unchanged, but the left mastoid and middle ear contamed fluid on soft tissue (Figs 5-7). More than 1 year after surgery, the appearance of the external auditory canal at otoscopy

temporal

fragmented,

wall

dehiscent

of the

wall

seen

material-enhanced

Milwaukee)

attenuation ated from

244.78

180:211-213

HE posterior

osseous

abnormalities,

was

meglumine [Conrayj; St Louis) computed to(CT) (GE 9800; GE Medical

the posteromedial Index

fluid

a

bone showed both mastoids to be well developed. The right middle ear was clear (Fig 1). On the left, the mandibular condyle

Joints,

tym-

this defect,

ear.

contrast

Systems,

of the

Through of senous

in the middle

of an acute

Neck

Joint’

panic

skull base. Two patients are described in whom dehiscence of the temporo-

cause

and

MD

Dehiscent The appearance

MD

portion

osseous

of the

tube

course,

runs

the

bone.

anteromedi-

one-third

whereupon The

within

temporal

for approximately

total

portion,

enclosed

of its

it becomes

anterior

20-25

mm

caris

cartilaginous medially and superiorly and membranous laterally and inferionly.

The

course

of the

cartilaginous

tube is a gradual curve antenomedially and inferionly to its orifice in the nasopharynx

The

(4).

normal

eustachian vents refiux

into

resting

the tympanic

ing, sneezing, and chian tube opens,

middle

position

tube is closed, of nasopharyngeal

ear secretions

cavity. yawning, allowing

into

of the

which

With

precontents

swallow-

the eustadrainage of

the nasophar211

1.

2.

3.

Figures

1-3. Case 1. Axial CT scans. (1) Bone algorithm. The left mastoid is well developed wall of the glenoid fossa is deficient (long arrow). The right middle ear is clean (arrowhead). fragmented from the

(short TM joint

arrow). herniates

The posterior postenomedially

ynx and equalization of pressure tween middle ear and nasopharynx. This

opening

of the

facilitated

eustachian

by a complex

various

muscles,

veli palatini

be-

the levator

is

of tensor

veli pala-

tube fails to open dysfunction or middle ear secreThe middle ear muto absorb oxygen and

continues

falls below

ear pressure

ambient

pressure. die ear

Negative pressure in the midcauses middle ear mucosa to be-

additional

results. carcinoma arising

Nasopharyngeal

of the

the adult. A benign of the panapharyngeal press

the

tube.

Between

osseous

space

aspect

by a tumor

Lange

and tube

adenoids nasal

dren (4) have been The rare congenital the petrous tympanic

orifice,

of the in

apex cavity

the

be

skull

adults

oc-

base.

and

exten-

and

chil-

implicated as well. cholesteatoma of

may expand and obstruct

of the eustachian

eustachian

may

in children

polyposis

tube mass

can corn-

of the

origin

eustachian

cluded sive

lateral

eustachian on malignant

tube

Obstruction of the may also be functional.

into the the origin

(6). eustachian tube Four muscles

have their origin on insertion in relation to the eustachian tube: tensor veli palatini, levator veli palatini, tensor ympani, and salpingopharyngeus. The tensor sible

tube. tini (4).

veli for

palatini

active

A portion is known

appears

dilation

of

212

eustachian

of the tensor veli as the dilator tubae

palamuscle

to cause

a spasm

tini and

tensor

described. #{149} Radiology

Spasm

dysfunctube have

of the medial

joint

dysfunction

has been of the

tensor

tympani

pterygoid

niscus

muscle.

muscle He

mittent

veli

had

not

logic

or

pala-

the

the

in

in

in

before

pearance of prior

opening

and and

allowed adjacent

the condyle the glenoid

could wall

to obstruct

tympanum. In our second

case,

the

in

in

the

this anterior

wing

base,

The ated

of the sphenoid,

are

that

able

tube.

translation

could

then

joint

of

the

translation reduced blocked

(protympanum)

kept the middle ear and mastoid clear. Although no procedure was performed on the glenoid or condyle, orthognathic may

have

indirectly

the condyle

posteriorly

dially,

pushing

tissue

preexisting

glenoid

defect.

through

More

TM

some

of the

decreasing

seems

joint

in

TM

but

the

best

in both the

not

the

permitted

explana-

of our

osseous

restrict

appearance

in a well-pneumatized

the

directs and

relieved

bulge seen at otoscopy decompressing the

me-

likely,

patient anterior

structures

soft

tissues

herniation

of in

patients. The

and

obstructed the

condyle

findings

normally

both

they

obstruction of the middle of the eustachian tube

Defects

that

scan.

henniwhere and

mouth,

thus

for the

cases.

reposi-

tioned

soft

tion

the

CT

tube.

Mechanical ear entrance

have that activity

audito

the

displacement

contents,

be displaced medially. Each time the patient opened hen mouth, anterior of the condyle would the soft-tissue herniation the protympanum. This

on

When

her

posterior

eustachian

joint

long fixation) The bulge

external

seen

to open

to

(and

corresponded

where

eustachian

tissues

TM

fixation,

of the

was

eliminating the and, presumably,

the

of

a continuous

hypothesis. wall

known to be deficient in patients with neunofibromatosis. As in case 1, the soft around

caused

soft tissues of the TM joint posteriorly into the defect, were detected at otoscopy,

they the

notably

move-

reduction

at otoscopy

defect

of the

skull

jaw

intermaxillary

canal

as other

the greater

and

strengthens

was

of the

eliminating

again over a year later removal of intermaxillary

that the patient had a congenitally dehiscent TM joint. This seems reasonable, bones

related

posteromedially,

we hypothesize

to become or

prevented

temporary

clear after

the

meso-

examination

the

that

at radio-

fact that the appearance of the ear at CT changed from clear surgery, to highly attenuating after surgery when the patient was

soon a

tory

some soft tissues within to the TM joint to herniate

posteromedially

and

inter-

function.

of the condyle was evidence trauma. The force of a blow suf-

ficient to fragment have also disrupted

an

obstruction

hindering

dehiscence

and

from

by

is

tissue

demonstrated

which

The middle

the tube

posterior

condyle

block of the mesotympanum. When intermaxillary fixation was discontinued, the resumption of normal jaw movements allowed normal eustachian tube

pa-

a swallow. Although muscular, this abnormality would be considered mechanical obstruction. In our first case, the fragmented ap-

The

caused tube

physical

ments,

tients with overbite, this muscle is unden so little tension that it bunches up against the wall of the eustachian tube

prevents

been

chewing

sphenomethat,

fixation eustachian

apparent,

the

arrow).

Low-attenuation

intermaxillary

the eustathe tensor eustachian to accumu-

proposed

(short

The left mandibular

algorithm.

reported

(7). Since

palatini dilates dysfunction of may leave the allowing fluid

lateral

surgery

Various forms of muscular tion affecting the eustachian

been

to be responthe

(TM

attenuating

algorithm.

(3) Soft-tissue

during

on near the fossa of Rosenmuller is one of the most frequent causes of mechanical obstruction

(long arrows). (arrow).

syndrome)

highly

(2) Bone

late in the mastoid and middle ear. Costen (7) called the superior head of the

middle

come engorged and exude fluid (5). A serous effusion

muscle

pain

tensor veli chian tube, veli palatini tube closed,

tini. If the eustachian because of muscular physical obstruction, tions cannot drain. cosa

is discontinuous mesotympanum

ptenygoid

tube the

of the glenoid into the anterior

and

interaction

including

and

wall

but

attention skull

base.

of an

acute

temporal to We

the

nasopharynx

add

to the

effusion

bone list of July

1991

6.

5.

Figures

4-8.

algonihm,

Case

2.

(4) Axial

preoperative

ular condyle

soft-tissue

The left mandib-

is small and dysplastic

and its long axis is rior than the normal right head). Adenoidal tissue in (A ) is normal for age. Both

(straight

more anteropostecondyle (arrowthe nasopharynx mastoids are clear

arrow),

(wavy

CT,

scan.

arrows).

(5) Axial CT, bone algorithm, scan. As on the preoperative posterior wall of the left glenoid

postoperative study, the

fossa is dehiscent (long the intact right glenoid

arrows) compared with (‘hort arrow). The left

mastoid is highly attenuating (arrowhead) on this scan, which was obtained after surgery. (6) Axial CT, soft-tissue algorithm, postoperafive scan. As in 4, the small, abnormally on-’

ented

left condyle

through

ever, (small

of eustachian

rarely ‘FM

seen

joint,

tube

dehiscent

which

medial

can result

opment of an acute toid effusion. U

middle

obstruction

a

wall

of the

in the develear

and

mas-

References 1.

2.

theory.

Arch

Otolaryngol

502.

Volume

4.

5.

Duckert LG. Anatomy of the skull base, temporal bone, external ear and middle ear. In: Cummings CW, Fredrickson JM, Hanker LA, Krause CJ, Schuller DE, eds. Otolaryngology: head and neck surgery. Vol 4. St Louis: Mosby, 1986; 2561. Tos M, Stangerup SE, Havid G. Mastoid pneumatization: evidence of the environmental

3.

180

#{149} Number

I

1984;

110:

6.

7.

(large

dehiscent

arrowhead) gienoid

protrudes

(small

arrow-

head) and pushes soft tissue from the TM joint into the mesotympanum (large arrow). How-

8.

causes

the

Bergeron RT, Osborn AG, Som PM. Head and neck anatomy excluding the brain. St Louis: Mosby, 1984. Bluestone CD, Kline JO. Otitis media with effusion, atelectasis, and eustachian tube dysfunction. In: Bluestone CD, Stool SE, eds. Pediatric otolaryngology. 2nd ed. Vol 1. Philadelphia: Saunders, 1990. Swartz J. Imaging of the temporal bone: a text/atlas. New York: Thieme Medical Publishers, 1986. Graham MD, KeminkJL. Neoplasms. In: Cummings CW, Fredrickson JM, Harker LA, Krause CJ, Schuller DE, eds. Otolaryngology: head and neck surgery. Vol 3. St Louis: Mosby, 1986; 3047-3060. Costen JB. A syndrome of ear and sinus symptoms dependent upon disturbed fundtion of the temporomandibular joint. Ann Otol Rhinol Laryngol 1934; 43:1.

the

left

arrow).

postoperative mastoid are

mastoid (7)

is higi Coronal

scan. highly

The left attenuating

The small, dysplastic row) protrudes into pushes

soft

(8) Otoscopic

tissue

image

ly attenuating

Cf, bone

algorithm,

middle ear and (black arrow).

condyle (large white anhe mesotympanum and

with

it (small

white

of the left external

tory canal more than 1 year after surgery. There is a localized bulge (arrowheads)

arrow).

audiin the

anterior wall of the external auditory canal. The posterior wall of the canal (arrow) is normal, as is the tympanic membrane (T). A = anterior, P = posterior.

Radiology

#{149} 213