大腦淺靜脈系的磁共振成像觀察及其意義

1、大腦淺靜脈系的磁共振成像觀察及其意義        【中文摘要】目的觀察大腦淺靜脈系在磁共振靜脈成像(MRV)上的形態(tài)學特征,分析比較二維時間奔騰法磁共振靜脈成像(two-dimensional time of flight MRV,2D-TOF-MRV)與三維對比增強法磁共振靜脈成像(three-dimensional contrastenhancement MRV,3D-CE-MRV)間的差異,為顯微神經(jīng)外科術前手術進路方案的制定、腦靜脈系統(tǒng)疾病正確及時的診斷提供影像學依據(jù)。方法選擇16例經(jīng)臨床證實無腦靜脈血管

2、病變或損傷病人的全腦磁共振靜脈血管成像,每位受檢者首先進行非增強的2D-TOF-MRV成像方法,然后進行增強的3D-CE-MRV成像。將16例(32側)人腦淺靜脈系分為橋靜脈區(qū)和竇匯區(qū),橋靜脈又分為上矢狀竇組、小腦幕上組和蝶骨組3組進行影像觀測;竇匯區(qū)觀察上矢狀竇、直竇、竇匯及雙側橫竇的吻合關系,以及橫竇的引流上風。比較兩種核磁共振靜脈成像方法對上述各結構的顯示情況及有無統(tǒng)計學差異。結果1.上矢狀竇組橋靜脈:上矢狀竇前部有一缺乏橋靜脈注進段,CE-MRV和TOF-MRV觀測此段長度分別為52.02±11.23mm和52.16±9.18 mm,此組橋靜脈分布于缺乏段的前方和后

3、方;CE-MRV和TOF-MRV觀測此組橋靜脈大部分以銳角方式逆上矢狀竇血流方向注進,其比例分別為60.6%和52.9%;2.小腦幕上組橋靜脈分為橫竇組和巖部組2組;橋靜脈注進處的形態(tài)分為單干型、多干型和燭臺型;CE-MRV和TOF-MRV發(fā)現(xiàn)橋靜脈均來自顳枕葉的底面和外側面;CE-MRV和TOF-MRV觀察橫竇組橋靜脈的顯示率為90%;巖部組橋靜脈的顯示率分別為40%和47%。Labbe靜脈在CE-MRV和TOF-MRV的顯示率分別為78%和81%,CE-MRV和TOF-MRV觀察分別有53.6%和50%的LV屬于橫竇組。3.蝶骨組橋靜脈大腦中淺靜脈(SMCV)表現(xiàn)為缺如、單干、雙干或三干,

4、CE-MRV和TOF-MRV發(fā)現(xiàn)缺如SMCV的分別為12.5%和28.1%;CE-MRV和TOF-MRV均發(fā)現(xiàn)SMCV注進海綿竇和蝶頂竇;CE-MRV和TOF-MRV均可見來自額葉底面和外側面、基底靜脈及其屬支、顳葉的橋靜脈注進;CE-MRV和TOF-MRV觀察SMCV均勻數(shù)目分別為1.4支和1.3支,均勻直徑分別為3.7mm和3.9mm,兩者較接近。4.竇匯區(qū)竇匯分5型:型:即竇匯型,型:雙分支型,型:上矢狀竇分支直竇偏側型,型:直竇分支上矢狀竇偏側型,型:上矢狀竇和直竇均偏側型。兩種成像方法對型(6%,6%)和型(38%,44%)的顯示無明顯差別;對型及型的顯示有差別(56%,0;25%,

5、19%),P0.05。直竇分支上矢狀竇偏側型(型)以橫竇右側上風為主,雙分支型(型)以左右均衡為主,兩者無區(qū)別。結論CE-MRV和TOF-MRV兩種成像方法對橋靜脈的觀察無統(tǒng)計學差異;對竇匯區(qū)分型的觀察有統(tǒng)計學差異,但對橫竇上風的觀察上無差別;對大腦各組橋靜脈深進系統(tǒng)的觀察,可以豐富影像解剖學資料;熟悉橋靜脈及竇匯區(qū)的磁共振成像形態(tài)特征,有助于神經(jīng)外科手術進路的選擇和手術過程中更好地保護腦靜脈,避免術后并發(fā)癥的發(fā)生,也有助于臨床對腦靜脈系統(tǒng)疾病及時正確地診斷;MRV是腦靜脈系統(tǒng)疾病診斷和神經(jīng)外科手術術前檢查的有效手段,對神經(jīng)外科術前了解橋靜脈的情況,只需采用TOF-MRV成像方法:對竇匯區(qū)結構

6、及腦靜脈系統(tǒng)疾病的早期診斷,CE-MRV比TOF-MRV正確。');【Abstract】 Objectives To study the related microneurosurgical planning and morphological basis for the genesis of cerebral venous diseases and provide timely angiographic diagnosis for cerebral venous diseases accurately,the difference of CE-MRV and TOF-MRV of t

7、he superficial cerebrovenous system were analyzed.MethodsThis study involved 16 patients without cerebral venous diseases and damaged veins.Images of the superficial cerebrovenous system were obtained with TOF-MRV and CE-MRV.To investigate the imaging appearance,the superficial cerebrovenous system

8、was divided into two parts:the cerebral bridging veins and the region of the torcular Herophili.The cerebral bridging veins were divided into three groups:superior saggital group,supratentorial group and sphenoidal group.The region of the torcular Herophili is the anastomosis of superior saggital si

9、nus,strait sinus,sinus and transverse sinus.To compare the two ways of MRV and find out the difference between them.Results 1.Superior sagittal groupAnterior to the coronal suture was a segment of superior sagital sinus(SSS) void of bridging vein draining into.The length was 27.00±11.36mm and 2

10、7.00±11.09mm on the venogram obtained by CE-MRV and TOF-MRV respectively.Most of the bridging veins entered SSS from the posterior to the anterior at acute angle,the bridging veins on the venograms obtained by CE-MRV and TOF-MRV were 60.6%and 52.9%respectively.2.Supratentorial groupBased on the

11、 location of entering point,the bridging veins were divided into two subgroups: transverse sinus group and petrosal group.The configuration of the location of termination yields three types:single vein type,separated type,candelabra type.MRV dissection showed the bridging veins drained the lateral a

12、nd basal su*ce of the temporal and occipital lobe.The bridging veins entering transverse sinus were found both in 90%venograms obtained by CE-MRV and TOF-MRV.The bridging veins entering petrosal group were found in 40%and 47%venograms obtained by CE-MRV and TOF-MRV respectively.The sensitivity of de

13、picting Labbe veins(LV) on the venograms obtained by CE-MRV and TOF-MRV were 78%and 81%respectively. More than half of vein of Labbe entering points(53.6%and 50%) were transverse group. 3 Sphenoidal groupThe superficial middle cerebral veins(SMCV) were classified into four types according to the num

14、ber of stems draining into the dural sinus: hypoplastic,single stem,double stems and three stems.The percent of the hypoplastic observed in CE-MRV and TOF-MRV was 12.5%and 28.1%respectively.Both of the MRV reavealed the SMCVs drained into cavernous sinus or sphnoparietal sinus.Aside from SMCV,the br

15、idging veins draining the lateral and basal su*ce of frontal lobe and temporal lobe,basal vein of Rosenthal and its tributaries were found on the venograms obtained by CE-MRV and TOF-MRV.The number of SMCV was 1.4 and 1.3 respectively,the diameter of SMCV was 3.7mm and 3.9mm respectively.There are n

16、o difference about SMCV on the venograms obtained by CE-MRV and TOF-MRV. 4.The torcular HerophiliAccording to the relation among the sinus in the region of the torcular Herophili,all subjects in this study could be grouped into 5 types:Type, a confluence of sinuses existed;Type,the superior sagittal

17、 sinus and the straight sinus forked,and the forking of both sinuses joined to form the lateral sinuses;Type, the superior sagittal sinus equally drained into two lateral trasverse sinus,the straight sinus drained into one side.Type,he straight sinus drained into two lateral trasverse sinus,the supe

18、rior sagittal sinus drained into one side.Type,the sagittal sinus drained into one side and the straight sinus drained into the other.There were no difference to find Type(6%,6%)and Type(38%,44%) with CE-MRV and TOF-MRV.There were difference to find Type(56%,0%)and Type(25%,19%) with CE-MRV and TOF-MRV.Trasverse sinuse of the right side drainage was mostly found in Type, equal drainage was mostly found in Type.Conclusionthere were no difference about the study of the cerebral bridging veins on the venograms obtained by CE-MRV and TOF-MRV;there were different about the types of the orc