Journal of the Korean Radiological Society, 1994 ; 30( 1) : 19 - 26

CTand MR Findings of Cavernous Sinus lesions'

Mee Young Cho, M.D. , Seon Hee Park, M .D. , Sang Hum Yoon, M.D. , ‘Jong Deok Kim , M.D.

PU RPOSE: To classify the cavernous sinus lesions, to describe their radiologlcal findings, and to assess the usefulness of MR compared to CT.

MATERIALS AND METHODS: Fourty-five patients with lesions involving the cavernous sinus proved by histological and/ or clinical and imaging methods were studied retrospectively and classified into neoplastic, vascular, and inflammatory lesions. CT and MR findings were compared in 21 patients evaluated by both modalities simultaneously according to these 4 categories.

RESULTS: Pitiutary macroadenoma was the most common cavernous sinus lesion(42%). Diffuse convex bulging of the lateral wall of cavernous sinus was the most frequent radiological finding(84%). and the others were encasement of the cavernous carotid artery(49%). remodelling of the surrounding bones(44%). and complete obl iteration of Meckel ’s cave(38%). in descending order of frequency. Bulging of the lateral wall of cavernous sinus was equally well demonstrated on both modalities, but encasement or displacement of the cavernous carotid artery and complete or paπial obliteration of Meckel’ s cave were much better delineated on MR than on CT with the ratio of 3.8: 1 and 4.6: 1 , respectively. Only bone changes were much better demonstrated on CTthan on MR with the ratio of 3.8: 1.

CONCLUSION: MR is superior to CT in demonstrating the cavernous carotid artery encasement and obliteration of Meckel’ s cave. but CTismuch betterthan MR in dem­onstrating bone changes.

Index Words : Cavernous sinus Cavernous carotid artery Cavernous sinus lesion, CTand MR Pituitary macroadenoma

other anatomical structures. The sensitivity of MR in INTRODUCTION the detection of cavernous or pericavernous lesions

exceeds that of CT. Coronal sections are the most in-High - resolution CT(HRCT) enables direct visuali- formative in the evaluation of cavernous sinus and

zation of the cavernous sinus and its neurovascular cranial nerves because their long axis lies in the axial contents. The changes in size, density , and configur- plane(3 -4) ation of the cavernous sinus are useful signs in The purposes of this study are to classify the cavern-detecting cavernous sinus diseases(1 -2). MR superbly ous sinus lesions, to describe their radiological depticts cranial nerves , internal carotid arteries , and findings , and to assess the usefulness of MR compared

with that of CT. 1 이논문은 1 993년도인제연구장학재단의 연구보조비로이루어졌음 2 Departm ent ofD iagnostic Radiology, College 01 Medicine, lnje University Received January 18, AcceptedJune1 6, 1993 Address reprinted requestto : Mee Young Cho, M. D., DepartmentofD iagnostic Radilogy, College 01 Medicine, Inje University, 633-15 Gaekum-dong, Pusanjin-Ku , Pusan 614-735, Korea

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MATERIALS and METHODS

We reviewed the findings of CT, MR and angio-

Journal of the Korean Radiological Society, 1994 : 30( 1) : 19 - 26

graphy in 45 patients with lesions involving the cavern­ous sinus(19 males and 26 females , 16 to 78 years old , mean age of 38) which were collected during a 4 -year period(July , 1988-June, 1992). AII patiens un- derwent more than two of those three studies within 2 weeks 。ne after another. The diagnoses were confirmed by pathology in 37 patients and by both clinical manifes­tation and imaging stadies in 8 patients (CCF, septic cavernous sinus thrombophlebitis , Tolosa - Hunt syn­drome). The cavernous sinus diseases were classified into neoplastic , vascular , and inflammatory lesions. The radiological findings by these 3 imaging techniques were classified into 4 categories ; bulging 。f the lateral wall of cavernous sinus(convex or straight) , invasion of the cavernous carotid artery (encasement or displacement) , obliteration of Mec­kel ’s cave (complete or partial) and change of the sur­rounding bones(remodelling , destruction , or hyperos­tosis). 80th CT and MR findings were compared in 21 patients according to these 4 categories.

CT was performed at a TCT -80A or TCT -300S (Toshiba , Japan) in 39 patients. lodinated contrast ma­terial was administrated by intravenous drip infusion. Axial and coronal CT images of brain were obtained with a 10- mm thickness and the cavernous sinus was scanned with a3 -5 • mm thickness.

Twenty -seven patients were scanned at a 0.5T MRT-50A superconducting scanner(Toshiba , Japan) , and

Table 1. Classification of Cavernous Sinus Lesions(n =45)

A. Tumors(33)(73 %)

1. Ben ign(27) (1) Pituitary macroadenoma (2) Meningioma (3) Trigeminal neuroma (4) Chondrochordoma (5) NF2

19(42%) 4( 9%) 2

2. Malignant(6) (1) Nasopharyngeal Ca (2) Palate liposarcoma

4( 9%)

(3) Metastasis from hepatom a B. Vasc미 ar Lesions(8)(18 %)

(1) C. C. F. 5(11 %) (2) Intracavernous ICA giant aneurysm 3

C. Inflammatory Lesions(4)(9%) (1) Cavernous sinus thrombophlebiti s 2 (2) Tolosa-Hunt syndrome (3) Sphenoid sinus mucocele

Total 45(100 %)

NF2 : neurofibromatosis type 11 C. C. F. : carotid-cavernous fistula ICA : internal carotid artery Ca. : carcinoma

axial and coronal short TRITE images were obtained with the parameters of 400/15/2 (TRITE/ exc itations) and double echo long TR coronal or aixal scans were performed with the parameters of 2500 -3000/30 , 120/1 -2. The slice thickness was 3 -5mm , the field of view was 25cm , and the matrix number was 256x256. Used contrast material was 0.1 mmol/kg of Gd - DTPA.

RESULTS

The diseases involving the cavernous sinus con­sisted of benign tumor(60 % , pituitary macroaden­。ma ， meningioma, trigemeinal neuroma, chondro­chordoma, neurofibromatosis) , malignant tumors (13%, nasopharyngeal carcinoma, palate liposarco­ma, metastatic hepatoma) , vascular lesions (18 % , CCF, giant aneurysm of cavernous carotid artery) , and inflammatory lesions (9% , septic cavernous sinus thrombophlebitis , Tolosa - Hunt syndrome , sphenoid sinus mucocele). Among these , pituitary marcroa­denoma was the most common disease representing 42 % of all cavernous sinus lesions(Table 1)‘

Of the radiological findings , diffuse convex bulging of the lateral wall of cavernous sinus(Fig. 1, 4) was the most common radi이 ogical finding (84%) and the others were encasement of the cavernous carotid ar­tery(49 %)(Fig. 1, 3, 5) , remodelling of the surrounding bones(44 %)(Fig. 1, 4). , and complete obliteration of Meckel ’s cave(38 %)(Fig. 3, 4). Ninty - five percent of all cases showed diffuse bulging of the lateral wall of the cavernous sinus when straight bulging(Fig. 3) was in­cluded. One of 4 meningiomas showed localized lat­eral bulging of the lateral wall of cavernous sinus(Fig. 2)‘ The lesion extended from the palatal liposarcoma showed localized , irregular convex bulging. Sixty­three percent of the benign tumors , 50 % of the malig­nant tumors , and 50 % of the inflammatory lesions revealed the cavernous carotid artery encasement,

which was diagnosed by MR and /or angiography. The cavernous carotid artery was surrounded and dis­placed by lesions in 4 of 33 tumors without changing its luminal diameter( Fig. 2) . It was classified as ‘ displace­ment’ ratherthan ‘ encasement' in our study(Table 2).

When the findings of CT were compared with those of MR in 21 patients , bulging of the lateral wall of caverous sinus was equally well demonstrated on both modalities(20: 21)(Fig. 1, 3, 4, 5) , but encasement(Fig 1, 3, 5) or displacement of the cavernous carotid artery and complete or partial obliteration of Meckel 's cave (Fig. 1) were much better delineated on MR than on CT with the ratios of 3.8: 1 and 4.6 : 1 , respectively. Only bone changes such as remodelling , destruction , and hyperostosis were much better demonstrated on CT than on MR with the ratio of3.8: 1 (Fig. 1, 4)(Table 3)

m

ω

Mee Young Cho, et 81: CT and MR Findings of Cavernous Sinus Lesions

a b

c d

DISCUSSION

MR could demonstrate the durallateral borders and the contents of the cavernous sinuses more effectively than CT could. The anatomic landmarks in MR studies , including cranial nerves 111 , V1 , and V2 , the venous space between V1 and V2 , and the carotid artery , can be used in the detection ofthe masses encroaching the cavernous sinuses. It is important to demonstrate the vascular encasement, that is , whether a blood vessel is surrounded by a lesion or not because it can alter the management plan. But, in the definition of bone erosion and destruction , or hyperostosis , MR is inferior to CT. However , when surgical intervention is considered ,

Fig. 1 . Pituitary macroadenoma. Post­contrast coronal CT(a) shows diffuse con­vex bulging 01 the right cavernous sinus by a large mi xed-density mass in the pitu­itary lossa with extension into all directions and remodelling 01 the sellar Iloor. On Gd-DTPA-enhanced coronal T1 WI(b) , obl iteration 01 the cavernous ICA and Meckel’s cave and the relationship between the mass and optic chiasm and inlundibulum , which are not demonst­rated on CT, are well seen. ICA encase­ment in addition to opening 01 the carotid siphon on sagittal T1WI (c) corresponds t。the angiographic lindings(d)

angiography still provides valuable anatomic infor­mations , such as , the vascularity of a tumor, the mor­phologic characteristics of aneurysm , and the nature of a caroti d -cavernous fistul a(CCF)(5 - 9)

The diseases involving cavernous sinus can be classified into inflammatory(e.g. , cavernous sinus thrombophlenitis , Tolosa - Hunt syndrome) , vascular( e. g. , aneurysm , CCF) , and ne。이 astic (e.g. , neuroma, meningioma, metastatic tumor) lesions (1 ， 1 이 Tolosa­Hunt syndrome is the most fr equently encountered in­flammatory disorder(11). Of the malignant cavernous sinus lesions, the majority is the lesions extended from nasopharyngeal carcinomas. As a result of our study , most of the cavernous sinus lesions were neoplastic (73 % ), followed by vascular(18 %) and inflammatory

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Journal of the Korean Radiological Society, 1994; 30( 1) ‘ 19 -26

Table 2. Radiological Findings 01 Cavernous Sinus Lesion(n =45)

~Fln~dlngs Lat wa|| bu|glng Cavernous ICA Obli t. Meckel ’s BoneChange Lesion ~ Convex Straight Encase Displace Complete Partial Remd Destruc Hyperos

Tumor(33)

Benign(27) 22 3 17 3 10 3 16 5 Malig. (6) 6 0 3 4 0 0 4 0

Vascular(8) 8 0 0 3 3 0 3 0 o Inflamm. (4) 2 2 2 o 0 0 0 o

TotaI(45)( %) 38(84) 5 22(49) 7 17(38) 3 20(44) 9

Lat. : lateral. ICA : internal carotid artery. Obl it. : obliteration. Remd. : remodelling . Destruc. : destruction Hyperos. : hyperostosis. Malig ‘ malignant. Inflamm. : ’nflammatory

a b c

Fig . 2. Meningioma. Axial T1WI(a) reveals a lobular, isointense mass arising Irom the right cavernous sinus with localized convex bulging and medial displacement 01 the cavernous ICA. Low signal intensities within the mass represent calcilications. On Gd-DTPA-enhanced axial(b) and coronal(c) T1 Wls , the mass is intensely and homogenously enhanced and displacement 01 the ICA by the mass is well seen ‘

lesions(9 %). Pituitary macroadenoma(Fig. 1) was the most common disease representing 42 % of all cavern­ous sinus lesions , followed by CCF(11 %), meningioma (9%)(Fig. 2) and nasopharyngeal carcinoma(9%)(Fig. 3). Nasopharyngeal carcinoma was the most common mal ignant tumor(4/6)

According to Kline et al. (2) who evaluated over 255 patients with sellar and parasellar lesions, CT criteria suggesting an abnormal cavernous sinus are: (a) asymmetry of size, (b) asymmetry of shape , particu­larly the lateral wall , (c) focal areas of abnormal density within the sinus. Ahmadi et al. (4) reported that CT findings of cavernous sinus invasion by pituitary aden­oma were the expansion of cavernus sinus and visible encasement of cavernous carotid artery. Among these , bulging of the lateral wall is the most sensitive indi­cator of pathologic involvement because , no matter

what the cause is, it leads to volume expansion of the involved cavernous sinus on CT(1 0).

Daniels et a l. (3 -4) reported MR signs of cavernous sinus lesions including obliteration of cavernous ca­rotid artery , bulging of the lateral wall of the cavernous sinus , and obscuration of cranial nerves on coronal images. Scotti et a l. (7) reported that the most sensitive MR sign of cavernous sinus invasion was an asym­metry in signal intensity between the two sides , and the most specific sign was carotid artery encasement, which , although not often present, was seen only in those patients with cavernous sinus invasion. Young et al. (6) observed the lateral displacement of the carotid artery may occur before encasement. They als。

reported that MR was superior to angiography when the tumor surrounded the carotid artery without chang­ing the diameter of its lumen , whereas , MR was equal

- 22 -

Mee Youn g Cho, et al : CT and MR Findings of Cavernous Sinus Lesion s

to angiography in the cases with luminal narrowing of

the artery after reviewing 11 patients with parasellar

masses. Coronal scanning appears to be the best

plane of MR imaging for the evaluation of encasement

and well correlated with the anteroposterior angio-

a b

gram. CT is ineffective in demonstrating the displace­

ment or encasement of the carotid artery because of

the concomitant enhancement of the carotid artery , the

cavernous sinus , and the mass itself(3 , 6) . In the evalu­

ation of the neighboring cranial nerves, we simply

c

Fig. 3. Nasopharyngeal carcinoma with intracranial extension. Postcontrast axial CT(a) reveals diffuse straight bulging of the right

cavernous sinus. On axial(b) and coronal(c) Gd-DTPA-enhanced T1 Wls diffuse encasement of the cavernous ICA and intracranial ex­

tension from the nasopharyngeal carcinoma are well demonstrated

a b c

Fig. 4. Giant aneurysm of cavernous IC A. Postcontrast axial CT( a) shows a uniformly enhancing mass in the right cavernous sinus with

remodelling of the sphenoid sinus. On axial T1 WI(b) , the mass shows an area of signal void containing hyperintense interior and per­

iphery, associated with phase-encoding artifacts. Follow-up axial T1 WI(c) reveals hyperintense aneurysm suggestive of thrombosis in

it after ligation of the cervicallCA

• 23 -

Fig. 5. Septic cavernous sinus thro­mbophlebitis. Postcontrast axial CT(a) reveals diffuse bulging of the right cavern­ous sinus containing a filling defect and exophthalmos. Superior ophthalmic vein was dilated on the upper section(not shown). Diffuse encasement of the cavernous ICA, brain abscess and menin­geal enhancement in the right temporal lobe are well demonstrated on Gd-DTPA enhanced coronal T1 WI (b). Peptostrepto­coccus was cultured in the peripheral blood ofthis patient

19 - 26 Journal of the Korean Radiol ogica l Society, 1994 ; 3D( 1)

Table 3. Compariosn ofCT & MRI Findings of Cavernous Sinus Lesion(n=21)

_________ Fi ndings

Lesion -------Tumor(16)

Benign(13) 13 13 4

Malig. (3) 2 3

Vascular(3) 3 |nflamm. (2) 2

Total(21) 20 21

Lat. ; latera/. Obli t. : obl iteration. Malig. : malignan t. Inflamm. : inflammatory

e

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때-야 -

m -

B

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야

Obli t. Meckel 's

CT MR

Cavernous ICA

CT MR

b

때-뻐

ns-미

-ku -뻐

-하

-T

L •

C

a

。α

‘l

nu

nU「Aa7

m 2

3

0

-며

9

2

3

0

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nι nu

--nu

-qu

1

3

3

2 -9

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can be demonstrated by CT or MR. Therefore, the true size of a giant aneurysm can usually be better assessed by CT or MR than by angiography. Angio­gram may underestimate the true size of a partially thrombosed giant aneurysm. With MR , the lumen of a giant aneurysm may appear as an area of signal vOid , or hypointense, or heterogeneous signal intensities, depending on the velocity and turbulence of the blood flow or the presence of thrombus. It is often associa­ted with phase-encoding artifacts. Meningiomas are isointense relative to brain parenchyme on T1-and T2-weighted images and show homogeneous en­hancement on Gd-DTPA T1-weighted images. Pituitary adenomas tend to have signal characteristics that are similar to those of normal pituitary gland itself, but many are partially cystic or hemorrhagic. Parasellar neoplasms other than meningiomas and pituitary adenomas are hypointense on T1- and hyperintense on T2-weighted images(2 , 5 , 12-14). In our cases, there was no diffic비 ty in differentiating the giant aneurysms from meningiomas and neuromas because of the sig­nal intensities of the former on MR , although all were

- 24

analysed whether the Meckel ’s cave , which contains the cranial nerve V1 and sometimes V2 , was obliterated or not instead of differentiating each cranial nerve(l ll , IV, VI) encroachment. The reasons why the gasserian ganglion lV1-V2 complex is consistently demonstrated on both CT and MR as a relatively sym­metric , oblong , intracavernous structure was not always possible to identify the cranial nerves in our series due to the effacement by the adjacent lesions. Complete obliteration of the Meckel ’s cave was observed in the benign and malignant tumors(Fig. 3) , giant aneurysms(Fig. 4) and CCFs. Remodelling of the surrounding bones was demonstrated in 60% ofthe be­nign tumors(Fig. 1) and in all giant aneurysms of cavernous carotid artery(Fig. 4) , but destruction was seen in 67 % of the malignant tumors and 21 % of the pit비tary macroadenoumas. Hyperostosis was demon­strated only in one of 4 meningiomas(Table 2).

Giant aneurysms show uniform enhancement on CT and are indistinguishable from neoplasms such as meningiomas or nerve sheath tumors. In giant aneurysms, there may be a sizable thrombus , which

homogeneous enhancing lesions on CT. According to

Yousem et a l. (15) the MR features of Tolosa - Hunt syn ­

drome are abnormal signals and/or mass lesions in the

cavernous sinus , enlarged cavernous sinus with or without convex outer margin and extension into the or­

bital apex. In our case , diffuse convex bulging ofthe lat­

eral wall of cavernous sinus and encasement of the

cavernous carotid artery without orbital extension

were seen on the initial MR , which were improved in accordance with clinical symptom on the follow-up MR

one month after steroid therapy. Reported CT findings

of septic cavernous sinus thrombosis are m비tiple ir­

regular filling defects in the enhancing cavernous

sinus , inflammatory changes in the orbital soft tissue, and enlargement of ophthalmic vein due to the exten­

sion of thrombophlebitis , which seem to be specific although there are many causes that show filling defects within enhancing cavernous sinus(10 , 16). Ad­

ditionally, air in the cavernous sinus can be a sign of septic cavernous sinus thrombosis(17) , but was not

seen in our cases. In one of 2 cases with septic cavern­

ous sinus thrombophlebitis(Fig. 5) , MR showed ad­

ditionally brain abscesses and meningeal thickening in

the ipsilateral temporal lobe , which were improved

rapidly on follow-up MR after treatment with antibiotics.

A CCF may result from trauma or surgery , or may occur spontaneously. On CT, al l of our cases showed

homogenously intense enhancement of the bulged

cavernous sinus with complete obliteration of Meckel ’s

cave and orbital changes including proptosis , enlarge­

ment of the ophthalmic ve in , and thickening of the extraocular muscles.

In summary, pit비tary marcroadenoma was the most

com'mon cavernous sinus lesion in our 45 cases(42 % )

Of the radiological findings , diffuse convex bulging of

the lateral wall of cavernous sinus was the most fre­

quent finding(84 %), and the others were encasement of

the cavernous carotid artery(49 % ), remodelling of the surrounding bones(44 % ), and complete obliteration of

Meckel ’s cave(38 % ). Although the number of the cases

was small , we might conclude MR was superior to CT in

demonstrating the cavernous carotid artery encase­ment and obliteration of Meckel 's cave

Mee Youn g Cho, et al: CT and MR Findings of Cavernous Sinus Lesions

REFERENCES

1. Hasso AN , Pop PM, Thomson JR, et al. High resolution thin sec­tion computed tomography 01 the cavernous sinus Radiographics 1982 ; 2 : 83-100

2. Kl ine LB, Acker JD, Post MJD, et al. The cavernous sinus; a computed tomographic study. 1981 ; 2 : 299-305

3. Daniels DL, Pech P, Ma rk L, et al. Magneti c resonance imaging 01 the cavernous sinus. AJNR 1985; 6: 187-1 92

4. Daniels DL, Czervionke LF, Bonneville JF, et al. MR imag ing 01 the cavernous sinus; va lue 01 spin echo and gradient recalled echo images. AJNR 1988 ; 9 : 947 -952

5. Hirsch WL, Hryshko FR, Sekhar LN, et al. Comparison 01 MR imaging, CT, and angiography in the evaluation 01 the enlarged cavernous sinus. AJNR 1988 ‘ 9 907-915

6. Young SC, Grossman RI , Goldberg HI, et al. MR 01 vascu lar encasement in parasellar masses: comparison with angio­graphy and CT. AJNR 1988 ; 9 : 35-38

7. Scotti G, Yu CY, Dillon WP , et al. MR im ag ing 01 cavernous sinus involvement by pitu itary adenomas. AJNR 1988 ; 9 657-664

8. Ahmadi J, No rth CM, Segall HD, et al. Cavernous sinus invasion by pituitary adenomas. AJNR 1986 ; 6: 893-898

9. Moore T, Ganti SR, Mowad M, et al. CT and ang iography 01 pri­mary extradu ral juxtasel lar tumors. AJ NR 1985; 145 ‘ 491-496

10 정진욱!장기련，한문희등 ôH언정맥동질환에서의전산화단증촬영술 대한방사선의학회지 1988; 24(2) : 201 -212

11. Post MJD, Mendex DR, Kline LB, et al. Metastat ic disease to the cavernous sinus; clinical syndrome and CT diagnosis. J comput Assist Tomogr 1985 ; 9( 1) : 11 5-120

12. Tan WS, Wilbur AC, Malee MF. The role 01 the neurorad iologist in vascular disorders involving the orbit. Radiol Clin North Ameri 1987; 25( 4) : 849-861

13. Chakeres DW, Curtin A, Ford G. Magnetic resonance imaging 。 1 pituitary and parasellar abnormalit ies. Radio l Cli n North Ameri 1989; 27(2): 265-281

14. Lee CBP, Deck, MDF. Sellar and juxtasellar lesion. Detection with MR. Radiology 1985 ; 157: 143-147

15. Yousem DM , Atlas SW, Grossman RI, et al. MR imaging 01 T olosa-H unt synd rome. AJR 1990 ; 154: 167-170

16. Ahmad i J, Keane JR, Segal HD, et al. CT observations pertinent to septic cavern ous sinus thrombosis. AJNR 1985; 6: 735-758

17. Curnes JT‘ Creasy JL, Whaley RL, et al. Air in the cavernous sinus: a new sign 01 septic cavernous sinus th rombosis. AJNR 1987 ; 8 : 1 76-1 77

건

Journal of the Korean Radiological Society, 1994; 30( 1) : 19-26

대 한 방 사 선 의 학 회 지 1994; 30( 1) : 19- 26

해면정맥동 병변의 뇌 전산화단층촬영과 뇌 자기공명 영상 소견

조미영·박선회·윤상홈·김종덕

인제대학교 의과대학 진 단방사선과학교실

목 적:해면정맥돔 병변의 종류와 빈도를 알아보고 이들의 밤사선학적소견을 분석하여 CT와 MR의 유용성을 비교하고자

하였다.

대상 및 방법:조직병리학적 또는입상적 소견으로 확진된 해면정맥돔 병변 45예를후향적으로분석하여 질환별로분류하

고， 이 중 CT와 MR을 동시에 시행한 21예에서 방사선학적 소견들을 각각 서로 비교하여 이 두 영상의 유용성을 비교하였다.

결 과:뇌하수체거대선종이 가장 흔한 질환이었고(42% ) ， 방사선학적 소견으로는 해면정맥동 측벽의 미만성 볼록팽창

(84% ) , 해면정맥동부위 내경돔맥의 미만성 협착(49%) ， 주위골의 재형성(44%) 및 Meckel동 폐색(38%)의 순이었다. 해면

정맥동 측벽의 미만성 볼록 팽창은 CT와 MR 둘다에서 같은 정도로 잘 볼 수 있었지만 내경동맥의 협착이나 전위， 그리고

Meckel돔의 폐색은 MR에서 CT보다 각각 3.8: 1 과 4.6; 1의 비율로 더 잘 보였다. 그러나 주위 골변화의 발견은 CT가 훨씬 더

좋았다.(3.8 : 1).

결 론:해면정맥동 병변에서 내경동맥의 협착과 Meckel동 폐색의 관찰에는 MR이 CT보다 좋으나， 주위 글변화를 보는 데

에는 CT가 MR보다 좋다.

- 26-