大韓放射線뽑學會끓‘ 第 26卷 第 6 號 pp. 1104 -1115 , 1990 Journal 01 Korean Radiological Soc ielY, 26(6) 1104 - 1115, 1990

CT of Cholesteatomas - In Respect to Bony Complications-

Hyung Jin Kim, M.D. , Hae Gyeong Chung, M.D. , Jae Chul Gong, M.D. , Si Ok Shin, M.D.*, Sea Young Jeon, M.D.**, Byeong Hoon Lim, M.D.***,

Jae Hyoung Kim, Young Soo Do, M.D. , Sung Hoon Chung, M.D.

〈국문초록〉

Department of Radiology, College of Medicine, Gyeong Sang Nationa1 University

중이 진주종의 전산화단츰촬영 소견

-골미란을 중심으로-

경상대학교 의과대학 방사선과학교실

김 형 진 • 정 혜 경 • 공 재 절 • 신 시 옥 •• 전 시 영 ••

임 병 훈*** • 김 재 형 • 도 영 수 • 정 성 훈

저자들은 최근 147H 월동안 경상대학병원에서 수술로 확진된 28례 의 중이 진주종의 전산화단층촬영

(CT ) 소견을 골미란을 중심으로 분석하였다. 수술로 명확히 범위를 확인할 수 있었던 23례의 진주종 중 1 6례에서 CT 소견은 수술 소견과 일치하였으나 나머지 7례에서는 동반된 육아조직과 진주종의 경계 를 나누기는 불가능하였다. 28례중 16례에서 경판과 상고실 외측벽의 미란이 있었다. CT는 92%에서

이소골의 상태를 정확히 판정했으며 이소골중 침골의 장돌기가 가장 많이 침범되어 있었다. 7례에서 골

성미로의 미란이 관찰되었는데 7례 모두에서 륙반규관의 침범이 있었다. 안면신경관의 미란은 6례에서

관찰되었는데 와우각 부분의 제 1슬부의 원위부와 유양돌기의 수직부에 각각 3례씩의 미란이 있었다. 고

실개와 S자상 정맥통판의 미란은 각각 4례와 6례에서 관찰되었다. 3례에서 두부내 합병중이 있었는바

이 들 모두에서 S자상 정맥통판의 미란이 동반되었으며 ， 이중 2례는 측정맥동 혈전증이었고 1례 는 경막

외 농양이었다 3례에서 파괴된 외이도를 통해 진주중이 바깥으로 유출된 자연유돌절제술 ( automasto­

idectomy) 의 소견을 보였으며 2례에서는 유양동을 채우고 있는 진주종이 자연유돌절제술에서와 비슷한

골파괴를 통반하고 있어 진주종의 유출이 엄박했음올 짐작케했다. 아울러 저자들은 수술로 확진된 3례

의 재발성 진주종에 대해 간단히 기술했다. 저자들은 고해상력 CT가 진주종의 진단 및 치료방법을 결

정하는데 있어서 가장 유용하리라는 것을 믿어 의심치 않는 바이다.

• 충북대학교 의과대학 이비인후과학교실 ‘ Department of OtolaIγngology. COllege of Medicine. Chungbuk NationaJ University • 경상대학교 의과대학 이비인후과학교실

•• Department of Otolaryngology. College of Medicine. Gyeongsang NationaJ University • 경상대학교 의과대학 신경과학교실

••• Department of Neurology. College of Medicine. Gyeongsang NationaJ University 이 논문은 1 989년 경상대학교병원 임상연구비의 일부지원으로 이루어졌음

이 논문은 1990년 7월 20일 접수하여 1990년 10월 23일에 채택되었음 Received July 20 , accepted October 23 , 1990

- 1104 -

- Hyung Jin Kim , et al.. CT of Cholesteatoma

- Abstract-

We retrospectively analized tweniy-eight cases of surgically confirmed cholesteatoma with

CT putting emphasis on the following items: (1) location and extent of cholesteatoma ; (2)

erosion of scutum and lateral attic wall; (3) erosion of the ossicles; (4) erosion of the bony

labyrinth ; (5) erosion of the facial nerve canal; (6) erosion of the tegmen ; (7) erosion of the

sigmoid sinus plate; (8) erosion of the bony external auditory canal; and (9) intracranial

complications. CT correctly predicted extent of 16 cases among surgically well documented 23

cholesteatomas. It was difficult to differentiate cholesteatoma from granulation tissue. Erosion

of the scutum and / or lateral attic wall was seen in 16 cases (57 %). The diagnostic accuracy of

CT in the evaluation of the status of the ossicles was 92% (22/24). The most commonly

involved portion of the ossicles was the long process of incus. There were seven cases having

erosion of the bony labyrinth. Lateral semicircular canal was exclusively eroded. Coronal CT

depicted erosion of lateral semicircular canal more accurately. Facial nerve canal erosion was

found in six cases (21 %). Eroded portion was dist외 Iimb of the first genu and mastoid

segment each in three cases. Erosion of tegmen and sigmoid sinus plate was identified in

four (14 %) and six cases (21 %J. respectively. There were three cases of intracranial complica­

tion , manifest as lateral sinus thrombosis in two cases and epidural abscess in one case. AlI

these three cases had erosion of the sigmoid sinus plate. We experienced three cases of “ aut­

omastoidectomy" and two cases of “ impending automastoidectomy". In both of these tw:o cond­

itions , the patterns of erosion of EAC were very similar. The only difference was that whether

the spontaneous drainage of cholesteatomatous mass had occurred or not yet. At the end of

this issue , we brie f1y comment the CT findings of recurrent cholesteatoma we experienced in

three cases. We believe high-resolution CT is a very reliable method and should be the first

step in the evaluation of cholesteatoma.

Index Words: Ear, CT, 2 1. 12ll

Temporal bone , CT. 2 1. 1211

Cholesteatoma. 2 1.264

A cholesteatoma. or more adequately kera­

toma. is a sac of keratinizing stratified squam­

ous epithelium within the middle ear space or

other pneumatized areas of the petrous bone.

Since the advent and the technical development

of Computerized Tomography(CT). it has proved

to be the most effective for detecting the bony

erosion associated with cholesteatomatous mas­

ses . We have correlated CT with surgical findings

of 28 cases of acquried cholesteatomas with sp­

ecial attention to their aggressiveness to erode

the a며acent bony structures. In addition. we

briefly discussed CT findings of postoperative re­

current cholesteatoma which we experienced in

three cases.

Materials and Methods

During the recent 14 months. we retrospectiv­

ely analized CT findings of 22 patients with

cholesteatoma and correlated them with surgical

findings. Six patients had a bilateral disease. so

we obtained overall 28 cases. The youngest was

five years old and the eldest was 55. The m에。r

clincial symptoms and signs were otorrhea in 19

patients. otalgia in 10. headache in 7. and verti­

go or dizziness in 6. and there were two patients

with a clinical evidence of facial nerve palsy and

- 1105 -

- 大韓放射線醫學會誌 : 第 26 卷 第 6 號 1990 -

one patient with seizure. All patients had some tomatous mass or if there was direct attachment

degree of conductive or mixed hearing loss. of mastoid portion of facial nerve to cholestea-

All patients had preoperative evaluation by a toma along is course on both axial and coronal

9800 scanner (GE Medical System, Milwaukee) images. We excluded evaluation of horizontal

using 1.5mm collimation with extended window portion of facial nerve canal, because a lot of

width of 4000 HU and with high-resolution bone cases had too extensive cholesteatoma to diffe-

algorithm. All underwent CT in the direct axial rentiate it from the mass.

(0 degree) and coronal (105 degree) planes. The

intravenous contrast medium was not given ex- Results

cept one in which case a noncholesteatomatous

tumor was clinically suspected. We obtained add- 1. Location and Extent of Cholesteatomas

itional enhanced brain scans, if there was a clin­

ical suspicion of an intracranial complication.

We had particularly paid attention to the foll

owing features: 1) location and extent of choles

teatoma; 2) erosion of scutum and/ or lateral at­

tic wall; 3) erosion of the ossicles ; 4) erosion of

the bony labyrinth ; 5) erosion of the facial nerve

canal; 6) erosion of the tegmen; 7) erosion of

the sigmoid sinus plate; 8) erosion of the bony

external auditory canal ; 9) presence of an intra­

cranical complication. We presumably thought it

a cholesteatoma as a whole , if there was a non­

dependent soft tissue within other spaces, con­

tiguous to an attic mass. We did not make efforts

to divide cholesteatoma into a pars flaccida or a

pars tensa type , because it would not change the

surgical methods in the presence of the overt CT

findings , and because there were many cases of

extensive cholesteatomas of which origin could

not be actually discerned. We exclued stapedi외

evaluation from this study, because there is a

limitation of CT to find it out consistently2 .3.4l

and because many surgical reports lacked the

statement about it. The erosion of the bony

labyrinth was considered to be definite , if both

axial and coronal scans showed the bony dehisc­

ence , and equivocal, if only either of the two

scans had a positive findings. Facial nerve canal

erosion was thought to be present, if there was

no identifiable thin bony plate to separate first

genu of facial nerve from an abutting cholestea

On CT , the soft tissue mass was present with­

in both attic and mastoid antrum in 25 cases

(89 %). In the other three cases , a small choles­

teatoma was confined to the epitympanum and

in one of the two , it was present purely within

the Prussak’s space (Fig. 1). Qf 25 atticoantral

cholesteatomas , there were seven cases of the

combined involvement in the mesotympanum ,

and fifteen cases of the hologympanic involvem­

ent. No cases showed a cholesteatoma confined

within the middle ear cavity other than the epit­

ympanum. External auditory canal was involved

by cholesteatoma in six cases(21 %). At surgerv ,

these findings were closely correlated in 16

cases . In seven cases in which a contiguous soft

tissue was present in the tympanic cavity other

than the ep파mpanum， it actually proved to be a

granulation tissue. In five cases , surgical notes

were incomplete or lacking about the extent of

cholesteatoma (Table 1).

In one case in which a noncholesteatomatous

tumor was clinically suspected, it was conside-

Table 1. Location and Extent of Cholesteatoma

atticoantral confined to attic

confined EMT* HT** CT 3

3 7 15

Op*** 10 10 3

* mesotympanum * * holotympanum * * * Excluding five cases of poor surgical record

1106

- Hyung Jin Kim , et al. : CT of Cholesteatoma

Fig. 1. Small cholesteatoma , coronal scan. A small soft tissue lesion is present only within Prussak‘s space (arrow) without ossicular erosion or displacement. Fig. 2. Infected cholesteatoma, axial scan. A large well-enhancing soft tissue mass (arrows) is found at the attic and mastoid , eroding the ossicles and additus ad antrum. The mass occupies the entire middle ear space on lower scans (not shown here ), and it proves to be an infected cholesteatoma.

rably enhanced on CT, and it proved an infected

cholesteatoma on the operation field (Fig. 2).

2. Erosion of scutum an션 ,. or lateral attic wall

Sixteen cases (57 %) had the erosion of scu­

tum and/ or lateral attic wall bya nearby choles­

teatoma.

3. Erosion of the ossicles

On CT , total or partial ossicular destruction

was noted in 22 cases. The involved ossicles were

malleus only in zero , incus only in seven , com­

bined malleus and incus in 15 cases. The most

commonly involved individual portion was the

long process of incus in 20 cases , followed by

body and short process of incus in 17 cases ,

head of maleus in 13 cases , and handle and neck

of malleus in seven cases. At surgery, these find-

could not correlated with surgical findings due

to the lack of surgical records about it. So , the

frequency of ossicular erosion according to sur­

gery was 67 % (16 / 24). There was no false nega­

tive case. Therefore , among surgically confirmed

24 cases , diagnostic accuracy of CT to detect

ossicular erosion was 92 % (22 / 24) (Table 2).

4. Erosion of the bony labyrinth

On CT , lateral semicircular canal erosion was

thought to be intact in 20 cases (71 %), equivo­

cal in four cases (1 4 %), and definte in four cases

(1 4 %), in one of which there was concomitant

erosion of vestibule and superior semicircular

canal (Fig. 4 a-c) . At surgery, all four cases that

erosion was thought as definite had positive ero­

sion. In four cases that we thought equivoc외，

ings were closely matched in 22 cases , including Table 2. CT Accuracy of Ossicular Erosion*

six cases with intact ossicles. There were two

cases of false positive findings , in which cases

the apparently small and irregularly marginated

ossicle on CT was intact , but was wrapped by

op\‘ T Positive Negative Total

Positive

16 2

18

Negative Total

o 16 6 8 6 24

cholesteatoma at surgery (Fig. 3). Four cases * Excluding four cases of poor surgical record

- 1107

- 大韓放射線홉學會誌 · 第 36 卷 第 6 號 1990 -

a Fig. ~. False positive case of ossicular erosion. axial(a) and coronal(b) scans. Cholesteatoma within the epitympanum surrounds the apparently small and irregular head of malleus and body of incus (arrow). The shape and position of the ossicles are well maintained. Note intact long process of incus and crus of stapes(b). At surgery. normal ossicles wrapped by cholesteatoma were seen.

c

b

Fig. 4 a-c. Massive cholesteatoma causing erosion of the bony labyrinth. axial(a) and coronal(b) scans. A huge cholesteatoma in the entire middle ear space and mastoid has caused massive erosion of vestibule and superior semicircular canal as well as lateral semicircular canal erosion (straight arrows in a and b). Posterior semicircular canal is intact(curved arrow in b). In addition. dist외 Iimb of labyrinthine portion of facial nerve canal is also destroyed (arrowhead in a) as well as lateral wall of mastoid. Air in the external ear is replaced by the soft tissue mass . and there is extensive erosion of posterior wall of external auditory canal. Compare these findings with that of normal contralateral ear shown in c.

- 1108 -

Hy ung Jin Kim , et al : CT 01 Cholesteatoma-

surgery confirmed the actual erosion in t l;1(ee cases (14 %) (Fig. 6 c , 8 b)

cases. In all these three cases , coronal scan corr­

ec t1y demonstrated the erosion (Fig. 5 a and b)

One of equivocal cases in which axial scan

showed erosion had intact canal at surgery

(Table 3).

5. Erosion of the facial nerve canal

On CT, erosion of the facial nerve canal was

found in six cases (22 %). In three cases (1 1 %),

the eroded portion was distal limb of the first

genu (Fig. 4 a) , and in the other three (11 %), it

was the vertical segment (Fig. 6 a-Ç, 8 a) . At

surgery, these findings proved correct in all

cases. There was no false negative case.

6. Erosion of the tegmen

On coronal scans , tegmen tympani and / or teg­

men mastoidea was seen to be eroded in four

Table 3. CT Accuracy of Erosion of LSCC'

o읍\ST Intact Equivocal Eroded TotaI

Intact 20 1 o 21 Eroded o 3 4 7

TotaI 20 4 4 28

‘ Lateral semicircular can외

7. Erosion of the sigmoid sinus plate

On axial scans , there were six cases (21 %) of

the erosion of sigmoid sinus' plate (Fig. 6 a , 9 a).

8. Erosion of the bony external auditory canal

(Automastoidectomy)

Three cases demonstrated erosion of the bony

external auditory canal at the pO!SLerosuperior

portion , resulting in spontaneous drainage of

much of cholesteatomatous debris through the

eroded external auditory canal (Fig. 7). This is

called 경utomastoidectomy". In two cases , there

was a lso an interesting findings , which we called

퍼npending automastoidectomy" , in which the

pattern of bony destruction was very similar to

“ automastoidectomy", but the cholesteatoma sti1l

resided in the mastoid antrum and middle ear

cleft , and so the expulsion of the cholesteatoma

would be very likely in the n earby future (Fig. 4 ,

8).

9. Intracranial complications

There were three cases of intracranial compl­

ication (11 % ) which was confirmed surgically.

a b Fig.5_ Discrepancy between axiaI(a) and coronaI(b) scans as to erosion oflateral semicircular canal . On coronal scan. there is no intervening septum between atticoantral cnolesteatoma and lateraI semicircular canal, which seems intact on axial scan. At surgery. lateral semicircular canal was dehiscent , as seen in b(arrow).

- 1109 -

- 大韓放射線醫學會誌 : 第 26 卷 第 6 號 1990 -

These were two cases of the lateral sinus throm- toma. that is. congenital and acquired5 .6l . Conge-

bosis (Fig. 9) and one case of the epidural absc- nital cholesteatoma is believed to arise from

ess. All three cases had the simultaneous erosion aberrant embryonic rests and comprises only 2

of the sigmoid sinus plate. % of all cholesteatomas. It is considered when a

cholesteatoma is found behind an intact tym-

Discussion panic membrane in a patient with no history of

otitis media. Acquired cholesteatomas account

There have been a lot of descriptions about the for the other 98 % and arise either from the pars

usefulness of CT in the field of otology. and it’s flaccida or from the pars tensa of the tympanic

of no doubt that CT is the most effective method membrane. The pars flaccida cholesteatomas

in the evaluation of cholesteatoma2-17l. A choles- comprise about four-fifths of all the acquired

teatoma is a sac of stratified squamous epithe- cholesteatomas. anå exclusively begin in the Pru-

lium filled with an accumulation of exfoliated ssak ’s space. There are many fine anatomic bar

kera tin that is trapped and growing within the riers to keep the disease limited in one comp

middle ear space or other pneumatized areas of artment of the middle ear space. particualrly in

petrous bone 1l . There are two types of cholestea - the attic7.8 l. The most common pathway of a

a b

c

Fig. 6. Erosion of facial nerve canal at mastoid segment, axial(a and b) and coronal(c) scans. The vertical segment offacial nerve canal directly attaches to a large botryoid cholesteatoma in the mastoid (arrows) . Cholesteatoma is 외so found in the entire middle ear. Notice the focal erosion of sigmoid sinus plate (arrowhead in a J. lateral semicircular canal (double arrowheads in b J. and tegmen tympan i( triple arrowheads in c)

1110

- Hyung Jin Kim , et al.: CT 01 Cholesteato ma-

a b Fig. 7. Automastoidectomy, axial(a) and coronal(b) scans. Direct communication of air-filled mastoid with external auditory canal is seen through the bony defect of posterosuperior portion of EAC in this patient having no history of previous operation. Note residual cholesteatoma in the mastoid

a b Fig. 8. Impeding automastoidectomy, axia l(a) and coronal(b) scans. This is the same case as in Fig.2. Huge cholesteatoma with entire ossicular erosion is present in the whole middle ear and m astoid. It has eroded entire posterosuperior wall of EAC and much of air in the EAC has been replaced by cholesteatoma. Also note erosion of vertical facial nerve canal (arrow in a) and tegmen tympani (a rrowheads in b).

pars flaccida cholesteatoma is via the superior The feature most suggestive of cholesteatoma

inculda l space to the posterior lateral attic and in a patient with middle ear opac ification is bone

subsequently through the aditus into the erosion. In fact . the absence of bone erosion with

antrum and mastoid51 . In this study. we did not middle ear opacification is more consistent with

categorize the individual type of acquired choles- uncomplicated inflammatory disease41 . The fact

teatomas. because it would not have affected sur- that a ll th e pa rs flaccida cholesteatomas arise

g ical procedures in the face of straightforward from Prussak's space from which th ey extend

CT findings and because there were many cases with a preferentia l pathway will h ave us under-

of an extensive cholesteatoma. the origin of stood th e frequ ency of erosion of the scutum and

which was h a rdly ide ntifiable. lateral a ttic wall . as s een in our cases (57 % ). It

- 1111

大옳放射線醫學會誌 : 第 26 卷 第 6 號 1990

has been reported that cholesteatoma is associa­

ted with ossicular erosion in 50-90 %4.9) and

that CT can predict this preoperatively with acc­

uracy rates ranging from 89 % to 94 %2.10).

Among surgically correlated 24 cases. we noted

ossicular erosion in 18 cases on CT. Surgery

confirmed this in 16 cases. In two false positive

cases. normal ossicle was surrounded by choles­

teatomatous mass without erosion (Fig. 3) We

think it is difficu1t to evaluate the status of oss­

icle when the cholesteatomatous mass surrounds

the apparen t1y small and irregular ossicle. In

that case. the gross shape and relationship of

the ossicles may be helpful in the evaluation of

its erosion

It is crucial to warn the surgeon about the

more serious complications. such as erosion of

the bony labyrinth. erosion of the facial nerve

cana1. erosion of the tegmen. erosion of the sig­

moid sinus plate. and other intracranial com­

plications. The propensity for erosion of the bony

labyrinth. especially lateral semicircular cana1. by

the cholesteatoma is well-known. and it occ­

urred in 25 % (7/28) in this study. ln one of our

series. an extensive cholesteatoma caused

marked destruction of bony coverings of vestib­

ule and superior semicircular canal as well as

lateral semicircular canal (Fig. 4). There have

been different opinions as to the optimal scan

method for evaluation of lateral semicircular can

al2 .4 •5 .6 ). In our series. coronal scans showed the

erosion of lateral semicircular canal more accura-

tely than axial scans did (7/7 vs 4/7) (Fig. 5).

Furthermore. in one case in which only axial

scan demonstrated erosion. surgery confirmed

lateral semircircular canal intac t. It probably re

sulted from the slight obliquity of lateral semicir­

cular canal to zero degree plane which we used

on axial scans. We think coronal scan is prefer

able to axial scan in the evaluation of the state of

lateral semicircular canal. if nonoblique true

axial and coronal scans are used. At times. cho-

lesteatoma assaults the facial nerve canal result­

ing in facial palsy. It is said to occur in 1. 1 %5).

This is especially like1y to occur in the region of

the first j:(enu at the level of the cochlea or in the

horizontal portion of the undersurface of lateral

semicircular cana1. In our cases. there were six

cases of facial nerve canal erosion (21 %). the

portion of which was the first genu in three

cases (Fig. 4 a) and the mastoid segment in the

other three cases (Fig. 6. 8 a). In the latter cases.

there was a large cholesteatoma extending into

the lowermost part of mastoid. The reason for

much higher frequency of facial nerve canal ero­

sion seems to be due to large numbers of more

extensive and far-advanced disease in our series

There was no false positive cases. Needless to

say. it should be derived from the methodology

we adopted. It is well known that the horizontal

portion of facial nerve canal is normally dehis­

cent in a considerable proportion of patients.

and that the partial volume averaging effect

mimcks erosion of facial nerve canal when a cho­

lesteatomatous mass just abuts thin bony plate

of ηmpanic segment2 .4 .5.6.1이. So. we exlcuded

evaluation of horizontal tympanic segment of fa­

cial nerve canal in this study. In the viewpoint of

significance of facial nerve canal erosion. the

most important thing, we think. is to correlate

CT with clinical signs.

The most serious and potentially fatal compli­

cation of cholesteatoma is intracranial extension

resulting in meningitis. intracerebral. subdural

or epidural abscesses. and venous sinus thromb­

osis 1). It has been markedly decreased in the era

of antibiotics. We experienced three cases of int­

racranial complications (11 %). These were two

cases of lateral sinus thrombosis (Fig. 9) and one

case of eqidural abscess. All these three cases

허so had concomitant erosion of the sig찌oid

sinus plate. In my opinion it is thoughtful to

obtain additional enhanced brain scans when

there is evidence of erosion of the sigmoid sinus

- 1112

- Hyung Jin Kim , et al.: CT of Choles teatoma -

a b Fig. 9 a, b. Lateral sinus thrombosis. Large cholesteatoma in the mastoid has caused the erosion of sigmoid sinus plate (arrow in a). On enhanced brain scan , rim-enhancing lesion due to lateral sinus thrombosis is seen at the region of sigmoid sinus (arrowheads in b)

plate on axial CT.

Three cases of our 28 previously nonoperated

cholesteatomas had another uncommon but uni­

que characteristic of cholesteatoma , so called,

“ automastoidectomy" (Fig. 7). In this variant

there is a central air collection, replacement of

the bony septa of the mastoid antrum , erosion of

the middle ear cavity, and a mural debris , all of

which are reminiscent of postsurgical ear4). lt is

the result of spontaneous drainage of cholestea­

toma through the destroyed external auditory

canal at superoposterior portion. ln two cases

there was also an very interesting findings which

we called 퍼npending automastoidectomy". The

pattern of bony destruction is very similar to

that of automastoidectomy, but the cholestea­

toma still resides in the mastoid and middle ear

space , so the expulsion of it is likely to be very

imminent (Fig. 4 , 8).

Las tly, we11 briefly mention the findings of re­

current cholesteatoma after mastoidectomy ,

whiCh we have en countered in three cases. The

type and extent of middle ear and mastoid sur­

gery depends on the a mount of disease en cou nt-

1113

ered. Mastoidectomy can be divided into cJose­

d-cavity types , in which the external auditory

canal (EAC) wall is ma inta ined , and open-cavity

types , in which the EAC walls a re taken down

posteriorly. The cJosed-cavity operations a re fu ­

rther subdivided into the simple m astoidectomy

and the intact can a l wall mastoidectomy , a nd the

open-cavity procedures into the radical m as to­

idectomy and the midified radical m asto idect­

omy ' :l) . Two of our three cases had undergone

open-cavity surgery , a nd one undergon e clo­

sed- cavity surgery. In short, recurrent cholestea

toma was demonstrated either as a well demar­

cated soft tissue mass outlined by air (Fig. 10) or

as an irregula rly marginated mass filling mastoid

or middle ear space with or withou t bone ero ­

sion3 .14

). No case showed any in tact ossicJe at alJ.

We could n ot dete rmine whether it was caused

by the previous opera tion or by th e recurrent or

res idua l cholestea toma. Nevertheless , we think

CT can afford the s urgeon not only the knowle­

dge of th e type of previous operation but the ex­

tent a nd associated complications of recurrent

cholesteatoma

- 大韓放射線醫學會픔 . 第 26 卷 第 6 號 1990

a b Fig.l0. Recurrent cholesteatoma. axial(a) and coronal(b) scans. This thirty three-year old woman had a history of mastoidectomy five years ago. On CT. there is absence of the superoposterior wall of EAC as w.ell as surgical window at the mastoid. Well-demarcated soft tissue mass surrounded by air is well demonstrated within the mastoid bowel. The cholesteatoma is a lso seen at the posterior mesotympanum (arrowheads in a). Note the similarities to the findings of “automastoidectomy" shown in Fig. 7.

Regardless of his or her preferred approach.

every surgeon wants to know the extent and

location of cholesteatoma preoperatively. Need­

less to say. high resolution CT would suffice it.

In addition. it should be the procedure of choice

in the e、raluation of bone erosion complicated by

cholesteatoma.

REFERENCES

temporal bone cholesteatomas. JCAT 1985 ;

9(3):519-523

5. Swartz JD. Cholesteatomas of the middle ear.

RCNA 1984; 22:15-35

6 . Virapongse C. Rothman SLG. Sasaki C. et a l. The

role of high resolution computed tomography in

evaluating disease of the middle ear. JCAT 1982;

6(4):711-720

7. Mafee MF. Kumar A. Yannias DA, et 외. Computed

tomography of the middle ear in the evaluation of

cholesteatomas and other soft tissue masses ‘

1. Proctor B. Chronic otitis media and mastoiditis. Comparison with pluridirectional tomography.

In: Paparella MM. Shumrick DA. eds. Otolaηπ19O- Radiology 1983; 148:465--472

logy. Vo1. 2 . The Ear. Philadelphia: W.B.Saunders 8. Mafee MF. Aimi K, Kahen HL. et 외. Chronic

Company. 1980: 1455-1489 otomastoiditis: A conceptu떠 understanding of

2. Mafee MF. Levin BC. Applebaum EL. et a l. CT findings. Radiology 1986; 160: 193-200

Cholesteatoma of the middle ear and mastoid: A 9. Swartz JD. Varghese S. Pars faccida choleste-

comparison of CT scan and operative findings atoma as demonstrated by computed tomo-

Otolaryngol Clin North Am 1988; 22(1):265- graphy. Arch Otolaryngol 1984; 110:5 15-51 7

293 10. Holliday RA. Inflammatory diseases of the tempor-

3 . Johnson DW. Voorhees RL. Lufkin RB. et al 외 bone:Evaluation with CT and MR. Seminars in

Cholesteatomas of the temporal bone: Role of Ultrasound. CT and MR 1989; 10(3):213-235

computed tomography. Radiology 1983; 11. Swartz JD. High-resolution computed tomog-

148:733- 737 raphy of the middle ear and mastoid. Part 1 :Nor-

4. Johnson DW. Hinshaw DB J r. . Hasso AN. et a l. mal radioanatomy including normal variations

Computed Tomography of local complications of Radiology 1983: 148:449--454

- 1114

- Hyung Jin Kim , et aL CT 01 Cholesteatoma

12. Swartz JD , Goodman RS , Russell KB , et a l.

High-resolution computed tomography of the

middle ear and mastoid. Part 2: Tubotympanic

disease. Radiology 1983; 148:455-459

13. Swartz JD , Goodman RS , Russell KB , et al

High-resolution computed tomography of the

middle ear and mastoid. Part 3: Surgically altered

anatomy and pathology. Radiology 1983;

148:461-464

14. Johnson DW. CT of the postsurgical ear. RCNA

1984; 22(1): 67-75

15. Shaffer KA , Haughton VM , Wilson CR. High

resolution computed tomography of the tempor외

bone. Radiology 1980 ; 134:409-4 14

16. Chakeres DW, Spiegel PK , A systematic technique

for comprehensive evaluation of the temporal

bone by computed tomography. Radiology 1983;

146:97-106

17. Ham SH. Ahn JS , Sung KB. et al. CT of temporal

bone: Part 2. OMPC. J Korean Radiol Society

1987; 23(5):669-677

- 1115 -