Journal of the Korean Radiological Society 1995: 32(6) : 859-864

MR Angiography in the Diagnosis of Cerebral Venous Angiomas: 3D TO F Versus Phase Contrast1

Hye-Young Choi , M.D. , Myung-Hyen Kim, M.D., Hyung-Chun Park, M.D2,

Min Hee Lee, M.D. , Yoo-Kyung Kim, M.D ., Sun-Wha Lee, M.D.

Purpose: To seek adequate sequence of MR angiography (MRA) on develop­mental venous anomaly in the brain.

Material and Methods: We collected ten cases who demonstrated developmen­tal venous anomaly on MR image. Eight patients among them, both 3D time­of-flight (TOF) with or without Gadolinium-DTPA enhancement and phase con­trast(PC) were performed: TOF without enhancement in five, TOFwith enhance­ment in six, and PCwith10cm/sec in five, PCwith 30cm/sec in three, and PCwith 5 cm/secvelocityencoding (VNEC) in two cases.

Results: On enhanced 3D TOF, both dilated collecting veins and medullary veins were well depicted in five of six cases, however, the signal intensity of the collecting and medullary veins are less than arteries. Dilated hyperintense collecting veins were well demonstrated on 3D PC with below the 10 cm/sec VNEC in all seven cases, but the medullary veins were poorly defined. Unen­hanced 3D TOF MRA could not reveal any dilated collecting and med비lary veins in all five cases.

Conclusion: Enhanced 3D TOF could demonstrate the collecting and medullary veins of developmental venous anomaly, however, 3D PC with below the 10 cm/sec VNEC could showthedilated collecting and largerdraining veins . We con­sidered that combined enhanced 3D TOF MRA and PC with VENC 10cm/sec can substitute for conventional angiogram in the diagnosis of developmental venous anomaly.

Index Words: Magnetic resonance (MR) , vascular studies Brain neoplasms, MR Angioma, central nervous system

INTRODUCTIOI\l

Venous angioma of the brain consists of multiple, radially oriented dilated medullary veins that drain into transcerebral collecting veins. Like the epidemiology and clinical signs and symptoms, the embryologic de­velopment of venous angioma is not well understood Recently, these lesions are not considered as a type of true vascular malformations but in an extreme anato­mic variant or developmental venous anomalies (DV­As). A prevailing developmental concept suggests that

' Oepartment이Radiology College 01 Medicine. Ewha Womans University 20epartment 01 Neurosurgery College 01 Medicine, Ewha Womans Un iversity Received October 12, 1995; Accepted May 8,1995 Address reprint requests to : Hye-Young Choi , Oepartment 01 Oiagnostic Radi­。logy ， College olMedicine, Ewha Womans University, Mokdong Hospital , # 911-1 , Mok-dong , Yangcheon-ku, Seoul , Korea 158- 056

these lesions represent an arrest of venous develop­ment, after arterial development is nearly complete. Such an arrest presumably results in the retention of primitive , embryologic medullary veins that drain into a single , large collecting vein (1). Today, most investi­gators(2 -7) consider that venous angioma of the brain is an incidental finding of little clinical relevance, and it rarely is associated with complications , such as he­morrhage. Venous angioma is a benign variety of intra­cranial vascular lesions(8) that is frequently disco­vered on contrast enhanced computed tomographic (CT) scans (9 , 1 이 or magnetic resonance(MR) studies (11 -16).

The MR angiography (MRI) findings of venous angi­oma were described on a few previous reports(1 , 17) We reported our experience of various MRA techni­ques in venous angioma. The main purpose of this study was to obtain adequate sequences of MRA in the

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Journ al of the Korean Radiological Society 1995: 32(6 ) ; 859- 864

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diagnosis of venous angioma in the brain. The MRA techn iques that we performed were three - dimensi­onal(30) ti me -of fl ight(TOF)(18 , 19) and phase -contrast (PC)(20, 21) MR angiography.

PATIENTS and METHODS

We experienced ten patients who demonstrated ve­nous angioma on conventional MR and/or CT images , which were examinedwith high resolution CT scanner (Hilight , GE Medical system , Milwaukee, USA) and 1.5 T superconducting MR (Signa, GE Medical Systems , Milwaukee, USA). Eight of them underwent both of 3D TOF and PC MRA with the Multisequence Vascular Pa­ckage(GE Medical Systems). Contrast enhanced 30 -TOF was also performed in six patients. 3D PC was done with variable velocity encodings , such as , 30cm /sec in two , 25cm/sec in one , 10cm/sec in five , 7 cm /sec in one and 5cm /sec in two patients. A 60-64 section 3D TOF and PC sequences required appro­x imately 9 minutes 28 seconds and 14 minutes 45 seconds respectively. The parameters of 3D TOF were as follows: 46/5.5-6.4/fr; one excitation ; 512 X 192 matrices ; fl ip angle , 250

; FOV, 16 -19 cm ; 1.0 mm thic­kness with magnetization transfer and ramped flip angle excitation saturations. 3D PC was performed as follows : 24 -35/8.5 -12.8; one excitation ; 256 X 128 matrices;flip angle , 15 - 20o ;FOV, 16 - 20cm ; 1.0mm

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Fig. 1. Forty three-year-old woman with in­cidental venous angioma a, b. Pre(a)- and post(b)-enhanced T1-weig­hted MR images show hypointense and en­hancing curvilinear draining and fine mottl ed medullary veins c. PC (10 cm /sec) MRA coronal(lVI : -90/0/0) image demonstrates hyperintense undu­lated draining vein into the internal cerebral vein (arrows) d‘ Enhancing TOF MRA coronal(lVI ; -90/0/0) image well depicts draining and “closed umbrella pattern" 이 medullary veins(arro­ws) in contrastto PC MRA

thickness with maximal velocity encoding of 5-30 cm/sec. For contrast enhancement, gadopentetate di ­meglum ine(Magnevist, ‘ SChering , Berlin) was admi­nistrated with 0.1 mmol/kg. We also used maximum in­tensity pr이ection (MIP) and interaxial vascular image (I VI) techn iques for better defined obl i que images of ve­nous angloma.

Our evaluation of MRA focused on two points ; the first was the capability to visualize the draining and medullary veins of venous angioma, and the second was to compare the intensities of draining and medul­lary veins between 30 -TOF and PC MRA techniques

RESULTS

Venous angioma was demonstrated by MR and/or CT images in 10 patients, five men and five women ranging in age from 7 to 48 years. Of our cases, seven were in supratentor ial and three in cerebellar hemi ­sphere. Venous angioma was mostly an incidental finding but was associated with nonspecific headache in four and cavernous hemangioma in two patients. There was one patient with a right orbital hemangioma

On T1 • weighted images, the main draining vein was hyp이 ntense in eight and is이 ntense in two patients. On T2 • weighted images the lesion was hyp이 ntense in five , hyperintense in two , mixed in two and isointense in one patien t. AII our cases revealed enhancing med-

Hye-Young Choi, et al: MR Angiography in the Diagnosis of Cerebral Venous Angiomas

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ullary and draining veins on enhanced T1 -weighted and/or CT images(Fig. 1 a, b, 2a , b, 3a)

On MRA, 3D PC image below the 10 cm /sec velocity encoding clearly showed the hyperintense dilated dra­ining veins in all eight ‘cases(Fig. 1 c, 2c, 3b). On the other hand, enhanced 3D TOF images were well de­picted the dilated draining as well as medullary veins in six patients except one whose medullary veins were faintly outlines. In this technique , the signal intensities of those veins were slightly less intense than those of arteries(Fig. 1 d, 2d , 3c). Enhanced 3D -TOF MRA find­ings were well correlated with conventional angiogra­phic finding(Fig. 3d). However , MR angiography with unenhanced 3D TOF could not demonstrate any dilated draining and medullary veins in five cases

DISCUSSION

Venous angioma in the brain is usually encountered as incidental findings in patients with nonspecific com­plaints. Neuropathologically they are composed of di­lated medullary veins , located in the white matter that converge towards a central dilated draining vein(8 - 10, 12). Saito and Kobayashi(22) suggested that venous angiomas occur when an accident in embryogenesis results in an occlusion or maldeveloment of the normal venous drainage of part of the brain. This assumption regarding the congenital nature of venous angiomas is also supported by the complete absence of normal draining veins in the region of the malformation and by venous infarction of the adjacent brain occurs following

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Fig. 2. Ten-year-old boy with headache for four years a. Enhanced CT reveals tubulardraining and medullary veins at the left deep cor­tico-medullary junction b. Proton-weighted MR image at the corre­sponding site of CT shows variable signal intensities which reflect variable velocities ofthe venous angioma(arrows) c. PC(10 cm/sec) MRA coronal(l VI ; -301010)

image reveals hyperintense dilated dra­ining vein that is connected with some fine medull ary veins(arrows)‘

d. Enhanced TOF MRA axial (IVI ; 01010) view nicely demonstrates “caput medusae" 이 medullary veins and draining vein (arrows)

removal of the venous angioma(2). Lasjaunias et al(4) suggested that the name “ venous angioma" should be changed to “ developmental venous anomaly" to reflect this characteristic more precisely. Therefore the lesion is purely venous , without increase in number or size of the arteries in or around the body of the venous angi­oma. Histopathologically, neuroglial tissue is found be­tween the abnormal vessels(15).

On magnetic resonance images, the venous angi­oma usually appeared as a hypointense tubular lesion with a “caput medusae" configuration on both T1 - and T2 - weighted images(11 -15). Coronal and sagittal im­ages could occasionally demonstrate the convergence of medullary veins to the transcerebral draining veins However, angiography is generally accepted as the di­agnostic standard for venous angiomas. The typical conventional angiographic image is that of radiating medullary veins , collecting centrally into a large dra­ining vein and terminating in a superficial cortical vein or a dural sinus (9 , 1 0, 22 , 23)

Previous reports have explored the efficacy of MRA in depicting intracranial vascular structures. However, the MRA findings of venous angioma have rarely been reported. Truwit(1) described briefly about the MRA sequences and its role in the diagnosis of intracranial venous angioma. Hustone et al(17) also reported the MRA findings in one patient with venous angioma. Our studies have used 3D -TOF(24, 25) and/or PC(26, 27) techniques for MRA of venous angioma in ten patients and we compared the MRA findings of venous angioma between those two different techniques.

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Journal of the Korean Radiological Society 1995 : 32(6) : 859-864

As we know, 3D TOF techniques clearly depict high velocity proximal arteries and the use of gadopentetate dimeglumine have optimized the visualization of ve­nous structures(28). These TOF principle could be ap­plied to demonstrate the medullary and draining veins of venous angioma. Six of our cases whose MRA was pertormed after contrast enhancement nicely demon­strated the medullary and draining veins together. Those MRA images by using MIP and IVI were compar­able to the images of conventional angiographic im­ages.

In contrast to TOF technique , the 3D PC technique permits flexible imaging of fast or slow flow by varying the amount of velocity encoding. With a maximum vel­ocity encoding of 5 cm/sec, motions as slow as cerebral spinal fluid flow can be demonstrated. In such se­quence , venous and arterial flow are aliased and not well seen. With a maximum velocity encoding of10-20 cm/sec, slow venous flow is well depicted. As the vel­ocity encoding is increased above 30 cm/sec , arterial flow is resolved and progressively less venous flow is demonstrated(19). So, PC MRA of venous angioma in our eight patients usually showed the draining veins of venous angioma with the low flow - encoding velocities of 5-10cm/sec.

In our study , the images by 3D PC with 10 cm/sec vel­ocity encoding and enhanced 3D -TOF directly depicted the medullary and draining veins because venous

a b

c

structures were of interest. Therefore , if the findings of venous angioma were typical on contrast enhanced MR images and MR angiography, we think that further in­vasive conventional angiographic examination could be avoided. We concluded that the most appropriate sequence of MRA in the diagnosis of venous angioma was the enhanced 3D TOF. Because the enhanced 3D TOF can demonstrate both the medullary and draining veins while 3D PC with velocity encoding of 10 cm/sec usually showed the draining veins only

REFERENCES

1. Truwit CL. Venous angi oma 01 the brain : history, signilicance ,

and imaging lindings, AJR 1992 ; 159 : 1299-1 307 2. Garn er T8 , Curling 00 Jr, Kelly OL Jr, Laster Ow. The natural

history 01 intracranial venous an gi omas. J Neurosurg 1991 ‘ 75 715-722

3. Kondziol ka 0, Oempsey PK , Lunslord LO. The case lor conserva­tive management 01 venous angiomas. Can J Neurol Sci 1991 ; 18 :295-299

Fig . 3. Twelve-year-이 d boy with hemorrhagic cavernous hemangioma a. Enhanced T1-weighted MR image shows enhancing I in ear draining and medu’lary veins near the Irontal horn 01 right lateral ventricl e(arrows) b. PC(1 0 cm/sec) MRA axial view represents hyperintense draining veins (arrows).

c. Enhanced TOF MRA oblique lateral (IVI ; 0/-30/0) view well demonstrates both “。pen­ed umbrella conliguration " 이 medullary ve­ins and dilated draining veins (arrows) Lobulated high signal intensity mass-like lesi on is an methemoglobin state 01 hemo­rrhagic cavernous hemangioma d. Lateral view ol carotid angiogram reveals typical radiating collection 01 medullary veins that are collected into large draining veins and terminating superlicial middle cerebral vei n(arrows)‘

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Hye- Young Choi, et al: MR Angiography in the Diagnosis of Cerebral Venous Angiomas

4. Lasjaunias P, Burrows P, Planet C. Developmental venous

anomalies(DVA) : the so-called venous angiomas. Neurosur Rev

1986 ; 9 : 233-244

5. Toro VE, GeyerCA, Sherman JL , Parisi JE, Brantley MJ. Cerebral

venous angiomas : MR lindings. J Comput Assist Tomogr 1988 ;

12 :935-940

6. Uchino A, Imada H, Ohno M. Magnetic resonance imaging 01 in­

tracranial venous angiomas. Clin Imaging 1990 ; 14: 309-314

7. Wilms G, Demaerel P, Marchl G, Baert AL, Plets C. Gadolinium­

enhanced MR imaging 01 cerebral venous angiomas with em­

phasis on their drainage. J Comput Assist Tomogr 1991 ; 15

199-206

8. McCormick WF. The pathology 01 vascular (arteriovenous) mal­

lormations. J Neurosurg 1966 ; 24: 807-816

9. Olson E, Gilmor RL , Richmond B. Cerebral venous angiomas

Radiology 1984; 151 : 97-1 04

10. Valavanis A , Wellauer J, Yasargil MG. The radilogical diagnosis

。1 cerebral venous angioma: cerebral angiography and com­

puted tomography. Neuroradiology 1983 ; 24 : 193-199

11 ‘ Augustyn GT, Scott JA, Olson E, Gilmor RL, Edwards MK. Cer­

ebral venous angiomas : MR imaging. Radiology 1985 ; 156

391-395

12. Cammarata C‘ Han JS, Haaga JR, Allidi RJ , Kaulman B. Cerebral

venous angiomas imaging by MR. Radiology 1985; 155: 639-643

13. Lee BCP, Herzberg L , Zimmerman RD , DeckMDF. MR imaging 01

cerebral vascular mallormations. AJNR 1985 ; 6 : 863-870

14. Scott JA , Augustyn GT, Gilmor RL , Mealey J Jr , Olson EW. Mag­

netic resonance imaging 01 a venous angioma. AJNR 1985;6

284-286

15. Wilms G, Marchal G, Hecke P, Fraeyenhoven L, Decrop E, Baert

AL. Cerebral venous angiomas: MR imaging at 1.5 tesla. Ne­

uroradiology 1990 ; 32 : 81-85

16. Kim MS, Park HJ, Joo AY. Gd- DTPA Enhanced MRI 01 the Cer­

ebral Venous Angiomas: Comparision with Cerebral Angio­

graphy. JKorean Radiol Sci1994 ; 30: 207-211

17. Hustone J 川 ， Rulenacht DA, Ehman RL, Wiebers DO. Intracranial

aneurysms and vascular mallormations: comparison 01 time-ol

Ilight and phase-contrast MR angiography. Radiology 1991 ; 181

721-730

18. Ruggier PM, Gerhard AL, Masaryk T J, Modic MT. Intracrainal cir­

culation: p비 se-sequence considerations in three-dimensional

(volume)MR angiography. Radiology 1989; 171 : 785-791

19. Keller PJ , Drayer BP , Fram EK , et al. MR angiography with

two-dimensional acquisition and three-dimensional display

Radiology 1989 ; 173: 527-532

20. Dumoulin CL , Hart HR. Magnetic resonance angiography. Radi­

ology 1986 ; 161 : 717-720

21. Dumoulin CL , Souza SP , Walker MF, Wagle W. Three-dimen­

sional phase contrast angiography. Magn Reson Med 1989 ; 9

139-149

22. Saito Y, Kobayashi N. Cerebral venous angiomas. Clinical evalu­

ation and possible etiology. Radiology 1981 ; 139 : 87-94

23. Ferstien SB , Pribram HW, Hieshima G. Angiography and com­

puted tomography in the evaluation 01 cerebral venous mal­

lormations. Neuroradiology 1979 ; 171 : 137-148

24. Masaryk T J, Modic MT, Ross JS, et al. Intracran ial circulation :

preliminary clinical results with three-dimensional(volume) MR

angiography. Radiology 1989 ; 171 ‘ 739-799

25. Edelman RR , Wentx KV‘ Mattle HP , 0 ’ Reilly GV. Intracerebral

arteriovenous mallormations ‘ evaluation with sel ective MR

angiography and venography. Radiology 1989 ; 173: 831-837

26. Spritzer CE, Pelc NJ, Lee LN , et a l. Rapid MR imaging 01 blood

Ilow with a phase-sensititive, limited-Ilip-angle, gradient reca­

lI ed p비se sequence: preliminary experience. Radiology 1990;

176: 255-262

27. Pernicone JR , Siebert JE, Potchen EJ , et al. Three-dimensional

phase-contrast MR angiography in the head and neck: prelimi ­

nary report. AJNR 1990 ; 11 : 457-466

28. Chakeres DW, Schmalbrock P, Brogan M , Yuan C , Cohen C. Nor­

mal venous anatomy 01 the brain: demonstration with gadopen­

tetate dimeglumine in enhanced 3D MR angiography. AJNR

1990 ; 11 : 11 07 -1 118

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Journal of the Korean Radiological Society 1995: 32(6) : 859- 864

대 한 방사선 의 학회 지 1995: 32(6) : 859-864

자기공명 혈관조영술을 이용한 정맥 혈관종의 진단: 3 Dimensional Time-of -Flight와 Phase Contrast의 비교1

1 이화여자대학교 의과대학 진 단방사선과학교실

201화여자대학교 의과대학 신경외과학교실

최혜열 · 김명현2 • 박형천2 • 이민흐1. 김유경 · 이선화

목 적:정맥혈관종 (뇌 정맥기형)의 진단을 위한자기공명혈관초영술(MRA)에서 적절한 pulse sequence를 찾아내고 3D

time-of-flight ( TOF)와 phase contrast (pc)에서 정맥기형의 소견과 그 차이점을 알아보고자 하였다.

대상 및 방법 :자기공명영상에서 정맥 혈관종으로 진단된 10여|중 3D TOF와 PC 기법으로 자기공명혈관조영술을 시행한 8

예를 대상으로 하였다. 3D TOF을 행한 환자중 6예는 조영증감을 하였고， 5예는 조영증강을 하지 않았다. 3D PC 혈관조영의

velocity encoding은 2예는 30cm/ seé, 1예는 25cm/sec, 5예는 lO cm/ sec, 그리고 7 cm/sec와 5cm/sec를 각각 1예씩 시행하

였다.

결 과:조영증강을 하고 시행한 3D TOF에서 6여| 모두 유입정맥과 수질정맥을 다 보여주었으나 이러한 정맥들의 신호강

도는 동맥보다 낮았다. 다앙한 velocity encoding을 얻은 3D PC 중 lO cm/ sec 이하의 velocity encoding에서는 수질정맥들은

잘 보이지 않았으나 유입정맥들은 고신호강도로 뚜렷이 나타났었다. 조영증강을 하지 않은 3D TOF에서늠 전 5여|에서 유입

및 수실정맥이 전혀 보이지 않았다.

결 론:조영증강을 한 3D TOF MRA는 정맥 혈관종의 진단에 있어서 고식적인 혈관조영술을 대치할 수 있을 것으로 사료

되었다.

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