海綿狀血管瘤

1、顱內(nèi)海綿狀血管瘤顱內(nèi)海綿狀血管瘤(intracranialcavernousangiomas,ICA)2005-8-26 起源與病變部位：起源與病變部位：研究證明海綿狀血管瘤是一種不完全外顯性的常染色體顯性遺傳性疾病，基因位于第7條染色體上 發(fā)病率：發(fā)病率：占腦血管畸形的25.1% ；人群發(fā)生率約為0.4%0.8% 分類：分類：腦內(nèi)型與腦外型 腦內(nèi)型發(fā)生在大腦半球占77%90%，病灶主要位于皮質(zhì)下區(qū) 腦外型海綿狀血管瘤較少見,常見于中顱窩底、鞍旁等部位,尤其海綿竇區(qū)。由于與硬膜關(guān)系密切,又稱為硬膜型海綿狀血管瘤海綿狀血管瘤是一種較常見的先天性血管畸海綿狀血管瘤是一種較常見的先天性血管畸形形Za

2、bramskiZabramski的分型標(biāo)準(zhǔn)的分型標(biāo)準(zhǔn) I型為亞急性出血者 II型為病灶反復(fù)出血及血栓形成者 III型為慢性出血者 IV型可能為微小ICA或毛細(xì)血管擴(kuò)張癥臨床特點(diǎn)臨床特點(diǎn) 見于各年齡組,然以3050歲居多,男女比例大致相等 臨床上常表現(xiàn)為反復(fù)出血和癲癇,進(jìn)而可引起神經(jīng)功能缺失,甚至危及生命 該瘤通常單發(fā)，單發(fā)病灶無癥狀患者占11%44 多發(fā)者僅6%13.4%,且多見于女性或有家族史者。多發(fā)性ICA臨床上往往出現(xiàn)神經(jīng)系統(tǒng)多個(gè)部位受損的癥狀和體征，而病程較單發(fā)ICA者短,而癲癇、顱高壓及神經(jīng)系統(tǒng)局灶癥狀體征多見,并可出現(xiàn)皮質(zhì)功能減退的表現(xiàn) 可伴發(fā)血管皮膚和其它臟器血管畸形及顱內(nèi)和椎管

3、內(nèi)其它腫瘤影像表現(xiàn)影像表現(xiàn) 腦內(nèi)CA直徑多較小，在23cm左右，腦外病灶直徑相對(duì)較大 CTCT平掃平掃表現(xiàn)為高密度,病灶中心常可見斑點(diǎn)狀鈣化，增強(qiáng)掃描病灶多呈輕至中度強(qiáng)化,如有血栓形成也可以不強(qiáng)化 MRIMRI表現(xiàn)表現(xiàn)具有一定的特異性，邊界清晰,病灶周圍無或輕度水腫,無或有輕微占位效應(yīng)。T1WI以等信號(hào)為主，T2WI以高信號(hào)為主的混雜信號(hào)，周邊有環(huán)形或弧形低信號(hào)帶環(huán)繞，混雜信號(hào)與病變內(nèi)鈣化、含鐵血黃素沉積及不同時(shí)期出血有關(guān) （與動(dòng)靜脈畸形的鑒別:后者病灶多較邊界不清，形態(tài)不規(guī)則，密度或信號(hào)不均勻，MRI示灶內(nèi)常見流空的血管）病理表現(xiàn)病理表現(xiàn) 海綿狀血管瘤為紅色圓形或分葉狀血管團(tuán),形似草莓或桑葚

4、,切面如海綿狀。與AVM不同,海綿狀血管瘤血流速度不快,缺乏明顯的供血?jiǎng)用}及引流靜脈 光鏡下,病灶由竇狀擴(kuò)張的畸形靜脈血管組成,血管壁薄,有單層的內(nèi)皮細(xì)胞和較薄的外膜,缺乏肌層和彈力纖維,管腔內(nèi)充滿血液，病灶內(nèi)見不同時(shí)期的出血、血栓、鈣化,出血腔的再上皮化，血管的增生和肉芽組織的增生可以使海綿狀血管瘤增大。病灶周邊也?？梢姾F血黃素沉著及反應(yīng)性膠質(zhì)增生，病灶內(nèi)不含神經(jīng)組織且分界清晰而有別于其它血管畸形。它可發(fā)生于中樞神經(jīng)系統(tǒng)的任何部位,以顱內(nèi)幕上多見 治療治療 理想的治療方法尚未確定。有認(rèn)為對(duì)無癥狀的較小CA可在臨床及CT或MR監(jiān)護(hù)下行保守治療，而多數(shù)認(rèn)為手術(shù)切除是治療CA的主要手段。手術(shù)死亡

5、率為2.7%7.5%，手術(shù)方法及效果取決于病灶位置。 Figure 1. Type 1 cavernous angioma in a symptomatic 8-year-old girl. (a) Transverse T1-weighted SE MR image shows a large lesion that includes a high-signal-intensity area (arrow) and a low-signal-intensity area (arrowhead) suggestive of recent bleeding in the left centrum

6、 ovale. (b) Transverse intermediate-weighted SE MR image confirms the presence of a large hemorrhagic lesion (arrow) in the left centrum ovale. The lesion is surrounded by edema (arrowhead). The diagnosis of acute hemorrhage related to a type 1 cavernous angioma was confirmed at surgery and patholog

7、ic analysis. Figure 2. Type 2 cavernous angioma in an asymptomatic 24-year-old man. (a) Transverse T1-weighted SE MR image shows a cavernous angioma in the right cingulate gyrus. The lesion includes a central reticulated core (arrow) and a peripheral low-signal-intensity rim (arrowhead). (b) Transve

8、rse T2-weighted fast SE MR image helps confirm the presence of a type 2 cavernous angioma in the right cingulate gyrus. The lesion has a core of heterogeneously high signal intensity (straight arrow) and a peripheral rim of low signal intensity (arrowhead) related to hemosiderin deposition. A second

9、 cavernous angioma (curved arrow) with the same MR imaging features is clearly demonstrated in the left frontal ascending gyrus. The surrounding rim is better demonstrated with a T2-weighted sequence, as in b, than with a T1-weighted sequence, Figure 3. Type 3 cavernous angioma in an asymptomatic 43

10、-year-old man. Transverse T2-weighted SE MR image (3,000/98) shows a small cavernous angioma (arrow) in the right cerebral hemisphere, close to the third ventricle and characterized by homogeneously low signal intensity.Figure 4. Type 4 cavernous angioma in an asymptomatic 40-year-old woman. Transve

11、rse T2-weighted GRE MR image shows a small low-signal-intensity lesion (arrow) in the right cerebellar hemisphere. .Imaging:The spin echo images demonstrate a well circumscribed berrylike lesion in the posterior midpons, which is characterized by mixed signal intensity, rim of hemosiderin, inhomogen

12、ous gadolinium enhancement, and absence of surrounding edemaHistory: This 53-year-old male truck driver presented with disabling rotatory nystagmus, which had gradually progressed over a 6-year period.大腦半球海綿狀血管瘤腦干海綿狀血管瘤脊髓海綿狀血管瘤治療治療 理想的治療方法尚未確定。有認(rèn)為對(duì)無癥狀的較小CA可在臨床及CT或MR監(jiān)護(hù)下行保守治療，而多數(shù)認(rèn)為手術(shù)切除是治療CA的主要手段。手術(shù)死亡率

13、為2.7%7.5%，手術(shù)方法及效果取決于病灶位置。 Figure 1. Type 1 cavernous angioma in a symptomatic 8-year-old girl. (a) Transverse T1-weighted SE MR image shows a large lesion that includes a high-signal-intensity area (arrow) and a low-signal-intensity area (arrowhead) suggestive of recent bleeding in the left centrum ovale. (b) Transverse intermediate-weighted SE MR image confirms the presence of a large hemorrhagic