腦腫瘤的病理和影像學(xué)特征

1、腦腫瘤的病理和影像學(xué)特征,華山醫(yī)院放射科 姚振威,腦外腫瘤的MR征象,提示征象周邊、廣基緊貼顱骨鄰近顱骨改變鄰近腦膜強(qiáng)化鄰近腦組織受推移遠(yuǎn)離顱骨,肯定征象腦組織和病灶間存在腦脊液間隙腦組織和病灶間可見血管間隔腫塊和白質(zhì)（水腫）間可見皮層結(jié)構(gòu) 硬（腦）膜外腫塊與腦組織間可見硬膜結(jié)構(gòu),低級(jí)星形細(xì)胞瘤,大體病理受侵腦組織腫脹，扭曲變形；浸潤(rùn)腫塊灰白質(zhì)面模糊；大體上可以為局限性的，也可彌漫地浸潤(rùn)?quán)徑X組織；偶爾呈囊性，可

2、見鈣化鏡下病理新生的分化較好的纖維型星形細(xì)胞和肥胖型星形細(xì)胞；組織結(jié)構(gòu)疏松，常有微囊變的腫瘤基質(zhì)；中度增生的腫瘤細(xì)胞實(shí)質(zhì)；偶爾出現(xiàn)核不典型變；缺乏有絲分裂或罕有；沒有微血管的增生及壞死組織分型：纖維型、肥胖型、原漿型分期及分級(jí)標(biāo)準(zhǔn)：WHOⅡ級(jí),CT表現(xiàn)平掃：境界不清的均勻的低/等密度腫塊；20%有鈣化；囊變罕見增強(qiáng)：無強(qiáng)化（若有強(qiáng)化則提示局部惡性變)MRI表現(xiàn)信號(hào)強(qiáng)度：T1WI低信號(hào)，T2WI及FLAIR高信號(hào)。

3、鈣化、囊變少見。出血、瘤周水腫罕見。可擴(kuò)散到鄰近腦組織可表現(xiàn)為局限性的，但可浸潤(rùn)?quán)徑X組織。通常無強(qiáng)化；強(qiáng)化則提示向高度惡性進(jìn)展 。DWI：通常缺乏限制性彌散 MRS：高Cho，低NAA，高M(jìn)I/Cr(0.85±0.25）,間變型星形細(xì)胞瘤,大體病理浸潤(rùn)性腫塊，邊界不清。結(jié)構(gòu)可以比較稀疏但侵襲鄰近組織。囊變，出血不常見鏡下病理結(jié)構(gòu)更密實(shí)。顯著的有絲分裂，核不典型變核漿比升高, 壞死及微血管增生?？沙?/p>

4、現(xiàn)肥胖細(xì)胞的變異WHO Ⅲ級(jí),CT表現(xiàn)平掃：低密度腫塊；鈣化罕見增強(qiáng)：大多數(shù)不強(qiáng)化MRI表現(xiàn)信號(hào)強(qiáng)度：T1WI為混雜等、低信號(hào)，T2WI、FLAIR為混雜的高信號(hào)。鈣化、出血、囊變罕見。增強(qiáng)掃描：通常無強(qiáng)化，可有局灶性、結(jié)節(jié)狀、均一、斑片狀強(qiáng)化。任何強(qiáng)化都應(yīng)提示膠質(zhì)母細(xì)胞瘤的可能。MRS：Cho/Cr升高，NAA降低,多形性膠質(zhì)母細(xì)胞瘤,大體病理絕大多數(shù)多形性膠質(zhì)母細(xì)胞瘤血供豐富。大體上可見出血；壞死核心周圍環(huán)繞

5、著灰紅色的腫瘤組織鏡下病理壞死，微血管增生星形細(xì)胞形態(tài)多樣顯著的核不典型變大量的有絲分裂分期與分級(jí)：WHO Ⅳ級(jí),CT表現(xiàn)平掃：周圍等密度，中心低密度，出血±，鈣化罕見。增強(qiáng)：顯著，不均勻，不規(guī)則強(qiáng)化MRI表現(xiàn)信號(hào)強(qiáng)度（通常為混雜性）：T1WI：等、低信號(hào)（可能有亞急性出血）；T2WI/FLAIR：高信號(hào)伴瘤周水腫，腫瘤的邊界超過異常信號(hào)之外動(dòng)態(tài)對(duì)比增強(qiáng)MRI能反映微血管的通透性，有助于腫瘤的分級(jí)診斷

6、,DSA：血供豐富，顯著的腫瘤染色，動(dòng)靜脈分流MRS：NAA、MI降低，Cho/Cr、乳酸/水升高DWI：比低度惡性的星型細(xì)胞瘤的ADC測(cè)量值低PWI：可鑒別GBM與低度惡性星型細(xì)胞瘤（GBM的rCBV高）,大腦膠質(zhì)瘤病,大體病理分兩種類型：1、腫瘤在腦組織上過度生長(zhǎng)或擴(kuò)展，但沒有明確的腫塊；2、彌漫性病灶＋局限性腫塊鏡下病理膠質(zhì)細(xì)胞拉長(zhǎng)，核深染，有絲分裂變異；膠質(zhì)細(xì)胞通常平行排列；沿有髓鞘的神經(jīng)纖維彌漫性浸潤(rùn)；微血管增生，

7、缺乏壞死；GFAP＋；細(xì)胞成分為主型的偶爾是少突膠質(zhì)細(xì)胞瘤分期與分級(jí)：通常WHO Ⅲ級(jí),CT表現(xiàn) 平掃：邊界不清，非對(duì)稱，低密度增強(qiáng)：通常不強(qiáng)化MRI表現(xiàn)T1WI：等/低信號(hào)T2WI/FLAIR：高信號(hào)輕度強(qiáng)化，局灶性強(qiáng)化可代表惡性膠質(zhì)瘤MRS：Cho/Cr、Cho/NAA升高，乳酸±，出現(xiàn)脂質(zhì)峰,大體病理境界清楚，質(zhì)軟、囊性、灰色腫塊。無包膜，質(zhì)地較硬，常伴囊變，有時(shí)囊變部分可大大超過瘤體本身，而將瘤體推向

8、一側(cè)形成壁結(jié)節(jié)鏡下病理腫瘤細(xì)胞多細(xì)長(zhǎng)，自細(xì)胞一端或兩端發(fā)出毛發(fā)絲狀纖維突起和嗜酸小體分期與分級(jí)：WHO Ⅰ級(jí),毛細(xì)胞型星形細(xì)胞瘤,CT表現(xiàn)平掃：小腦蚓部或小腦半球稀疏的囊/實(shí)性腫塊；無瘤周水腫；低/等密度；20％有鈣化增強(qiáng)：>95％強(qiáng)化（強(qiáng)化形式各異）MRI表現(xiàn)實(shí)性或結(jié)節(jié)在T1WI上低/等信號(hào)，T2WI上高信號(hào)。囊性成分在T2WI上高信號(hào)，F(xiàn)LAIR上不被抑制。不均勻強(qiáng)化。MRS：高Cho，低NAA，高

9、乳酸,ADULT PATIENTS WITH SUPRATENTORIAL PILOCYTIC ASTROCYTOMAS:A PROSPECTIVE MULTICENTER CLINICAL TRIAL. PAUL D. BROWN et al.Int. J. Radiation Oncology Biol. Phys., Vol. 58, No. 4, 1153–1160, 2004,PAUL D. BROWN et al. AD

10、ULT PATIENTS WITH SUPRATENTORIAL PILOCYTIC ASTROCYTOMAS:A PROSPECTIVE MULTICENTER CLINICAL TRIAL. I. J. Radiation Oncology ● Biology ● Physics Volume 58, Number 4, 2004,In adult:The temporal lobe was the most commonly in

11、volved site Malignant transformation is rare Favorable prognosis of adults with pilocytic astrocytomas with regard to survival and neurologic function. With an estimated 10-year survival rate of 95% Radiologic t

12、herapy need not be offered to adults with supra- tentorial pilocytic astrocytomas who have undergone gross or subtotal resection,室管膜下巨細(xì)胞型星形細(xì)胞瘤,多為結(jié)節(jié)性硬化伴發(fā)錯(cuò)構(gòu)瘤惡變大體病理邊界清楚的分葉狀腫塊。常見鈣化、囊變、豐富的血管鏡下病理典型者呈雙核或多核星形細(xì)胞，常見囊變、壞死

13、，可見大的腫脹星形細(xì)胞胞質(zhì)呈玻璃樣嗜酸性，分化良好，有絲分裂罕見分期與分級(jí)：WHO將其歸為Ⅰ級(jí),CT表現(xiàn)平掃：常見一側(cè)側(cè)腦室或二側(cè)側(cè)腦室擴(kuò)大, 腫瘤多呈低等混合密度，可見鈣化和囊變也可見沿紋狀體丘腦溝的室管膜下錯(cuò)構(gòu)結(jié)節(jié)，該結(jié)節(jié)呈等密度，伴鈣化或不伴鈣化增強(qiáng)：可見明顯不均勻強(qiáng)化動(dòng)態(tài)掃描顯示達(dá)峰值時(shí)間縮短，密度下降期延長(zhǎng)MRI表現(xiàn)平掃T1WI為低等混合信號(hào)，T2WI為等或高信號(hào)增強(qiáng)后常有明顯不均勻強(qiáng)化,Shunji Ni

14、shio et al. Subependymal giant cell astrocytoma: clinicaland neuroimaging features of four cases. Journal of Clinical Neuroscience(2001) 8(1), 31–34,There may be some academic debate as to whether subependymal nodules an

15、d SEGAs are two distinct lesions in respect of their growth potential, or are a continuum, in which small subependymal nodules without any growth potential are at one end and SEGAs without growth potential are at the oth

16、er end. Several authors have claimed that the ‘sube-pendymal nodules’, which are located near the foramen of Monro, are not or are only partially calcified and are enhanced after gadolinium, have a higher probability

17、 of evolving into a tumour, particularly in familial cases of TS.,subependymalnodules,Nabbout R, et al. Early diagnosis of subependymal giant cell astrocytoma in children with tuberous sclerosis. J Neurol Neurosurg Psych

18、iartry 1999; 66: 370–375.,多形黃色星形細(xì)胞瘤,大體病理鄰近腦膜的皮質(zhì)囊性腫塊伴壁結(jié)節(jié)鏡下病理腫瘤很明顯的位于皮質(zhì)區(qū)。多形性的表現(xiàn)：纖維性和巨大多核新生的星形細(xì)胞；大黃色瘤細(xì)胞（含脂肪成分）；密實(shí)的網(wǎng)狀結(jié)構(gòu)；淋巴細(xì)胞浸潤(rùn)。缺少壞死，有絲分裂；可伴皮質(zhì)發(fā)育不良分期與分級(jí)：WHO Ⅱ級(jí),CT表現(xiàn)平掃：囊性呈低密度伴混雜密度結(jié)節(jié)。實(shí)性呈低密度、高密度或混雜密度鈣化、出血、顱骨侵蝕罕見增強(qiáng)：有時(shí)顯著不均勻

19、強(qiáng)化MRI表現(xiàn)T1WI：低或混雜信號(hào); T2WI/FLAIR：高或混雜信號(hào)。 有些病例伴皮質(zhì)發(fā)育不良增強(qiáng)：通常中度或顯著強(qiáng)化，邊界清，偶見腦膜尾征,Pleomorphic xanthoastrocytoma: clinical, imaging and pathological features of four cases. Alfredo Bucciero et al.Clinical Neurology and Neuros

20、urgery 99 (1997) 40-45,少枝少突神經(jīng)膠質(zhì)瘤,一般病理情況：起源于皮質(zhì)，向皮質(zhì)下白質(zhì)生長(zhǎng)大體病理邊界清晰，粉灰色，柔軟的腫塊。位于皮質(zhì)，皮質(zhì)下白質(zhì)。鈣化常見。出血、囊變可見。鏡下病理中度增生的腫瘤細(xì)胞，偶爾伴有絲分裂。核圓、均質(zhì)，胞質(zhì)清晰。微小鈣化可見，囊變或黏液樣變?？捎胸S富的毛細(xì)血管網(wǎng)分期與分級(jí)：WHO Ⅱ級(jí)間變型少枝膠質(zhì)瘤：WHO Ⅲ級(jí),Engelhard HH, Stelea A, Cochran

21、 EJ. Oligodendroglioma: pathologyand molecular biology. Surg Neurol 2002;58:111–7.,CT表現(xiàn)平掃：低、等密度，大部分鈣化，出血少見，20％可見囊變?cè)鰪?qiáng)：程度不同MRI表現(xiàn)信號(hào)不均：T1WI上低、等信號(hào)，T2WI上高信號(hào)，出血，壞死罕見局限性，有輕度的瘤周水腫50％強(qiáng)化,室管膜瘤,大體病理邊界清。柔軟，分葉，灰粉色的腫塊。可見囊變，壞死，

22、出血。可越過第四腦室各孔，偶爾侵犯鄰近室管膜的腦組織鏡下病理腫瘤細(xì)胞圍繞血管排列形成假菊形團(tuán)，細(xì)胞成分中度。有絲分裂少，偶爾有核不典型變間變型室管膜瘤：細(xì)胞成分增多。核不典型變，染色過深。微血管增生。腫瘤細(xì)胞呈假柵欄樣排列伴多樣的壞死分期與分級(jí)：WHO Ⅱ級(jí)。WHO Ⅲ級(jí)（間變型）,CT表現(xiàn)平掃：大多數(shù)為等密度。可有出血，囊變，50％伴鈣化。常見腦積水增強(qiáng)：形式多樣的不均勻強(qiáng)化MRI表現(xiàn)信號(hào)混雜：T1WI上略低信號(hào)，T

23、2WI上等或低信號(hào)。常見鈣化，出血，囊變，血管流空多達(dá)90％伴腦積水增強(qiáng)：中度不均勻強(qiáng)化MRS：NAA/Cho，Cr/Cho較星形細(xì)胞瘤，髓母細(xì)胞瘤高,They are common tumors in children, comprising about 10% of paediatric CNS, while intraspinal ependymomas are more often in adults2/3 of the

24、 intracranial ependymomas are located in the infratentorial compartmentWhen in the fourth ventricle, they tend to conform to the ventricular cavity and extrude through the foramina of the fourth ventricle into the ciste

25、rnsCalcifications are not infrequent,while haemorrhage is rare,Holger Pettersson, et al. The encyclopaedia of medicle imaging(VI):neuroradiology and head and neck imaging.2000,脈絡(luò)叢腫瘤,大體病理局限性，乳頭狀腦室內(nèi)腫塊。囊變出血常見。兒童好發(fā)于側(cè)腦室三角區(qū)，

26、成人好發(fā)于第四腦室、橋小腦角池鏡下病理CPP：立方形上皮細(xì)胞伴纖維血管核心CPCa：細(xì)胞成分增多，核質(zhì)比例升高。核形態(tài)多樣，有絲分裂多見 分期與分級(jí)：CPP：WHO Ⅰ級(jí)；CPCa: WHO Ⅲ級(jí),CT表現(xiàn)平掃：75％等或低密度。腦積水。25％出現(xiàn)點(diǎn)狀鈣化。偶爾有出血，囊性增強(qiáng)：顯著均勻強(qiáng)化MRI表現(xiàn)T1WI上等低混雜信號(hào)增強(qiáng)：顯著強(qiáng)化CPP可出現(xiàn)局限性侵犯室管膜旁腦組織，但

27、范圍擴(kuò)大則提示CPCa?？梢娏骺宅F(xiàn)象，出血DSA：脈絡(luò)叢動(dòng)脈增粗，血管染色濃密，延遲，動(dòng)靜脈分流常見,Ji Hoon Shin et al. Choroid plexus papilloma in the posterior cranial fossaMR, CT, and angiographic findings.Journal of Clinical Imaging. 2001; 25: 154– 162Chitra

28、Sarkar et al. Choroid Plexus Papilloma:A Clinicopathological Study of 23 CasesSurg Neurol 1999;52:37–9,Propensity to arise at the foramen of Luschka with extraventricular extension Occasional peritumoral signal v

29、oids/cysts or calcification Weaker enhancement on MR or CT Less strong tumor staining by the anterior or posterior inferior cerebellar artery on angiography The lack of hydrocephalus of the extraventricular CP

30、Ps to overproduce CSF due to their having less blood supply than the intraventricular CPPs Tumoral calcification has been reported to be present in 24% of the CT cases of CPPs,Adult choroid plexus papill

31、oma in the posterior cranial fossa,節(jié)細(xì)胞膠質(zhì)瘤,病因－病理機(jī)制－病理生理：從膠質(zhì)錯(cuò)構(gòu)瘤或軟腦膜下顆粒細(xì)胞轉(zhuǎn)變而來；從胚胎性神經(jīng)母細(xì)胞瘤或PNET分化而來大體病理實(shí)性或囊性腫塊伴壁結(jié)節(jié)。常擴(kuò)展到腦皮質(zhì)鏡下病理神經(jīng)元變形，偶爾出現(xiàn)雙核。新生的膠質(zhì)細(xì)胞通常為星型細(xì)胞，GFAP+，有絲分裂罕見分期與分級(jí)：WHOⅠ級(jí)或Ⅱ級(jí)間變型節(jié)細(xì)胞膠質(zhì)瘤WHO Ⅲ級(jí)惡性伴膠質(zhì)母細(xì)胞瘤樣膠質(zhì)細(xì)胞罕見，WHO Ⅳ

32、級(jí),CT表現(xiàn)平掃：密度多樣：60％低密度，40％低等混雜密度，35％~40％有鈣化。表淺的病灶可擴(kuò)展到顱骨增強(qiáng)：約50％強(qiáng)化，中度不均勻強(qiáng)化MRI表現(xiàn)信號(hào)多樣：T1WI 上與灰質(zhì)信號(hào)相當(dāng)或略低，T2WI上稍高信號(hào)；FLAIR上不被抑制50％強(qiáng)化：中度不均勻強(qiáng)化50％伴皮質(zhì)發(fā)育不良MRS：Cho/Cr升高,15例神經(jīng)節(jié)細(xì)胞膠質(zhì)瘤實(shí)性與囊實(shí)性腫瘤 1 2例 ,實(shí)性部分呈長(zhǎng)或等Ｔ1長(zhǎng)Ｔ2信號(hào) ,信號(hào)不均勻 ,邊緣欠清或清。注

33、藥后腫瘤可有不規(guī)則增強(qiáng)或均勻增強(qiáng)。實(shí)性部分內(nèi)可有囊腔 ,鈣化或伴有出血。囊性腫瘤 3例 ,囊性部分呈等腦脊液信號(hào)顳葉的腫瘤伴有鈣化及腦內(nèi)囊性腫瘤應(yīng)與神經(jīng)節(jié)細(xì)胞膠質(zhì)瘤相鑒別,楊建華 ,高培毅 ,陸榮慶。中樞神經(jīng)系統(tǒng)神經(jīng)節(jié)細(xì)胞膠質(zhì)瘤的影像診斷。中國(guó)醫(yī)學(xué)影像技術(shù)　 2 0 0 2年　第 1 8卷　第 3期223-,They are circumscribed tumors that tend to have a cystic

34、 component and frequently calcify On CT they have different densities, but more frequently are iso- or hyperdense, and very often enhance with contrast,節(jié)細(xì)胞膠質(zhì)瘤 Ganglioglioma,Lagares A et al. Ganglioglioma

35、of the brainstem: report of three cases and review of the literature. Surg Neurol 2001;56:315–24.,Hypointense or isointense on T1-weighted imaging MRI Hyperintense on T2-weighted imaging, and has been shown to be e

36、ven more hyperintense on proton density imaging The tumor tends to be solid or at least have solid components, and the solid elements will usually, but not always, enhance with gadolinium Gangliogliomas demon

37、strate higher cerebral blood volume compared with other low-grade gliomas but the degree of vascular permeability in gangliogliomas is similar to other low-grade gliomas,節(jié)細(xì)胞膠質(zhì)瘤 Ganglioglioma,Zentner Jet al. G

38、angliogliomas clinical radiological, and histopathological findings in 51 patients. J Neurol Neurosurg Psychiatry 1994;57:1497–502M. Law et al. Conventional MR imaging with simultaneous measurements of cerebral blood vo

39、lume and vascular permeability in ganglioglioma. Magnetic Resonance Imaging 22 (2004) 599–606,M. Law et al.,胚胎發(fā)育不良性神經(jīng)上皮瘤,起源于發(fā)育不良的原始神經(jīng)外胚層細(xì)胞大體病理顳葉好發(fā)，腦回變厚鏡下病理多結(jié)節(jié)結(jié)構(gòu)。顯著特征：特異性的膠質(zhì)神經(jīng)元成分。與皮質(zhì)垂直的不同質(zhì)細(xì)胞呈柱狀排列。少枝突樣細(xì)胞圍繞血管排列。其他細(xì)胞可向星形

40、細(xì)胞，神經(jīng)元分化。微囊性變。鄰近皮質(zhì)發(fā)育不良分期與分級(jí)：WHO Ⅰ級(jí),CT表現(xiàn)平掃：楔性低密度灶。皮質(zhì)或皮質(zhì)下。30％延伸到腦室。20％有鈣化增強(qiáng)：80％不強(qiáng)化。20％結(jié)節(jié)或斑片樣強(qiáng)化MRI表現(xiàn)T1WI上低信號(hào)T2WI上高信號(hào)FLAIR低等混雜信號(hào)無瘤周水腫增強(qiáng)： 1/3表現(xiàn)為點(diǎn)狀或環(huán)形強(qiáng)化,Due to the slow growth, the cortical location(usually in the t

41、emporal lobe) and the frequent presence of cysts, skull remodeling with erosion of the inner and middle table is frequently found in associationAt CT or MR, enhancement is usually absent,Holger Pettersson, et al. The en

42、cyclopaedia of medicle imaging(VI):neuroradiology and head and neck imaging.2000,中央性神經(jīng)細(xì)胞瘤,大體病理色灰，質(zhì)脆，局限性的腦室內(nèi)腫塊。血供中等，可出血，鈣化鏡下病理類似少枝膠質(zhì)瘤。不規(guī)則的圓形細(xì)胞向神經(jīng)元分化可有不同的結(jié)構(gòu)形式：血管周圍假菊形團(tuán)（類似室管膜瘤）。蜂窩表現(xiàn)（類似少枝膠質(zhì)瘤）。大的纖維區(qū)（類似松果體瘤）良性，間變壞死罕見。偶爾出現(xiàn)

43、少量的有絲分裂，微血管增生分期與分級(jí)：WHO Ⅱ級(jí),CT表現(xiàn)平掃：通常實(shí)性和囊性低等密度。50％有鈣化。腦積水常見增強(qiáng)：中度不均勻強(qiáng)化MRI表現(xiàn)信號(hào)不均：T1WI上大多數(shù)與皮質(zhì)信號(hào)相等，T2WI上高信號(hào)部分病例可見流空效應(yīng)中度至顯著強(qiáng)化,Spiros Sgouros, F.R.C.S,et al. CENTRAL NEUROCYTOMA:A CORRELATIVE CLINICOPATHOLOGIC AND RADIO

44、LOGIC ANALYSIS.Surg Neurol 1998;49:197-204.von Deimling A, Janzer R, Kleihues P, Wiestler OD.Patterns of differentiation in central neurocytoma.Acta Neuropathol 1990;79:473-9,It affects mainly young patients in the se

45、condand third decade of life and is believed to arisefrom the neuronal cells of the septum pellucidurnand the subependymal plate of the lateral ventricles An entirely benign nature for this tumor is questioned and

46、 it appears that there may be malignant variants.Surgery should aim for maximum possible excision, as the location of the tumor allows. The role of postoperative radiotherapy remains controversial and may be considered i

47、n cases of subtotal excision of tumors with anaplastic histologic features. Chemotherapy may be of benefit in cases recurring despite,腦膜瘤,病因：起源于蛛網(wǎng)膜的帽狀細(xì)胞。大體病理邊界清晰，圓形或分葉狀，廣基底與硬腦膜相連骨質(zhì)增生硬化常見。非腫瘤性的硬膜增厚常見明顯的腦組織侵犯罕見鏡下病理亞型：

48、上皮型，纖維型，過渡型其他：血管瘤型，微囊型，分泌型，脊索樣型，不典型腦膜瘤，間變型腦膜瘤分期與分級(jí)：90％WHO Ⅰ級(jí)。 5％~7％WHO Ⅱ級(jí)（不典型，透明細(xì)胞型，脊索樣型）。1％~3％WHO Ⅲ級(jí)（間變型，乳頭型，桿狀型）,CT表現(xiàn)平掃：骨質(zhì)增生硬化，骨皮質(zhì)不規(guī)則，內(nèi)生骨疣常見。70％~75％低密度，20％~25％伴鈣化，2％~3％伴瘤內(nèi)或瘤旁囊變?cè)鰪?qiáng)：90％以上顯著強(qiáng)化MRI表現(xiàn)所有序列上的信號(hào)通常都與腦皮質(zhì)信號(hào)

49、相等50％~65％伴水腫25％不典型變（壞死，囊變，出血）90％以上顯著強(qiáng)化，常不均勻硬膜尾征：35％~80％出現(xiàn)，增厚的硬腦膜隨著遠(yuǎn)離腫瘤而逐漸變細(xì),其他表現(xiàn)DWI，ADC：多樣MRS：Cho/Cr與增生潛能相關(guān)，在1.5ppm出現(xiàn)丙氨酸峰提示腦膜瘤DSA：腫瘤周邊由軟腦膜血管供血，中心由硬腦膜血管供血,Nauta 分型：1型：囊腔或壞死腔位于腫瘤深部或中央，2型：囊腔或壞死腔位于腫瘤邊緣 (遠(yuǎn)顱內(nèi)側(cè))，3型：囊腔

50、位于腫瘤周圍腦組織內(nèi)，4型：囊腔位于腫瘤腦組織之間（擴(kuò)大的蛛網(wǎng)膜下腔），5型:與上述2型相仿，唯囊壁為纖維組織和腫瘤細(xì)胞島所組成（Worthington）。但Feliciani等認(rèn)為屬Nauta2型的亞型,囊性腦膜瘤,蛛 網(wǎng) 膜 下 腔,腦 組 織,囊 性 區(qū),腦 膜 瘤,NAUTA 4 型：囊性區(qū)位于腫瘤和腦組織之間，為擴(kuò)的蛛網(wǎng)膜下腔,NAUTA 2 型：囊性區(qū)位于腫瘤邊沿,NAUTA 1 型：囊性區(qū)位于腫瘤中央,NAUTA

51、 3 型：囊性區(qū)位于腫瘤鄰近腦組織內(nèi),惡性腦膜瘤,大體病理腫瘤較大，呈膨脹性或浸潤(rùn)性生長(zhǎng)，切面上多見出血、壞死、囊變鏡下病理有明顯的惡性腫瘤細(xì)胞表現(xiàn)；可見部分瘤組織保持典型的腦膜瘤結(jié)構(gòu)外，有惡性表現(xiàn)例如指狀浸潤(rùn)或彌漫浸潤(rùn)腦組織；瘤細(xì)胞豐富，細(xì)胞生長(zhǎng)活躍，核異型明顯，核大深染，可出現(xiàn)巨核細(xì)胞，核分裂相多見；常見壞死灶分期與分級(jí)：WHO歸為Ⅲ~Ⅳ級(jí),CT表現(xiàn)具有腦膜瘤的一般特征腫瘤邊緣不規(guī)則或呈鋸齒狀，邊界不清腫瘤平掃或

52、增強(qiáng)掃描顯示密度不均，斑片狀強(qiáng)化囊變，出血可見腫瘤周圍出現(xiàn)明顯水腫而本身無或僅輕微鈣化腫瘤附近明顯的骨質(zhì)破壞并可向顱外蔓延腫瘤侵犯半球呈蘑傘狀，又稱蘑菇征,MRI表現(xiàn)腫瘤信號(hào)不均勻較良性腦膜瘤多見增強(qiáng)后掃描病灶呈斑片狀或環(huán)狀強(qiáng)化腫瘤形態(tài)多不規(guī)則，輪廓呈分葉狀、結(jié)節(jié)狀或鋸齒狀腫瘤包膜不完整，厚薄不一，不完整處鏡下可見腫瘤組織侵犯并穿破包膜向腦內(nèi)浸潤(rùn)粗短不規(guī)則形硬膜尾征向顱內(nèi)外浸潤(rùn)生長(zhǎng)顱外遠(yuǎn)處轉(zhuǎn)移術(shù)后易復(fù)發(fā)MRS分析

53、，惡性腦膜瘤表現(xiàn)為NAA成分無或少，Cho/Cr比例升高，可見脂肪酸族代謝,腦浸潤(rùn)可發(fā)生于組織學(xué)上為良性、非典型性或間變性（惡性）腦膜瘤，有腦浸潤(rùn)的腦膜瘤較易復(fù)發(fā)，伴有組織學(xué)上腦浸潤(rùn)的良性腦膜瘤的臨床過程與非典型性腦膜瘤相似，但不出現(xiàn)非典型性和間變性（惡性）腦膜瘤的遺傳學(xué)（基因）改變。言外之義，腦浸潤(rùn)=非典型性腦膜瘤,陳星榮。 腦膜瘤。中國(guó)醫(yī)學(xué)計(jì)算機(jī)成像雜志。2002,腦浸潤(rùn)的確定性征象：腫瘤邊緣毛糙模糊，蘑菇征，偽足征（

54、腫瘤邊緣指狀突出），毛刷征，為腦浸潤(rùn)的確定性征象。腦浸潤(rùn)的提示性征象:腫瘤輪廓呈節(jié)結(jié)狀或分葉狀。,陳星榮。 腦膜瘤。中國(guó)醫(yī)學(xué)計(jì)算機(jī)成像雜志。2002,,,蘑菇征為腦浸潤(rùn)的確定性征象,,蛛網(wǎng)膜浸潤(rùn):擴(kuò)大蛛網(wǎng)膜下腔內(nèi)毛刺狀增強(qiáng),,血管外皮細(xì)胞瘤,大體病理許多血管外皮細(xì)胞瘤類似腦膜瘤。3／4為邊界清楚、質(zhì)硬、有包膜的分葉狀腫決?？捎袑捇蛘着c硬腦膜聯(lián)系。血管外皮細(xì)胞瘤為含有許多穿支血管的富血供腫瘤鏡下病理可見豐富的細(xì)胞和血管形

55、成致密的彌漫的網(wǎng)絡(luò)結(jié)構(gòu)，呈小葉狀排列的腫瘤細(xì)胞周圍繞以鹿角血管為其特征?？梢娪薪z分裂分期與分級(jí)：WHO將血管外皮細(xì)胞瘤歸為起源不明腫瘤類,CT表現(xiàn)平掃：多呈低等混合密度。其內(nèi)常見囊變或壞死。骨窗顯示病灶局部侵蝕性骨質(zhì)破壞增強(qiáng)：病灶呈不均勻強(qiáng)化MRI表現(xiàn)T1WI呈等信號(hào)， PDWI、 T2WI呈略高信號(hào)信號(hào)不均勻，與腫瘤壞死、囊變及腫瘤血管流空有關(guān)增強(qiáng)后掃描明顯不均勻強(qiáng)化,血管母細(xì)胞瘤,大體病理局限性邊界清晰，可見血管豐

56、富的結(jié)節(jié)，囊變鏡下病理通常囊壁壓迫腦組織而不是腫瘤實(shí)質(zhì)。結(jié)節(jié)成分為大的空泡樣的基質(zhì)細(xì)胞和豐富的毛細(xì)血管網(wǎng)分期與分級(jí)：WHO Ⅰ級(jí),CT表現(xiàn)平掃：低密度囊＋等密度結(jié)節(jié)增強(qiáng)：常見：結(jié)節(jié)顯著均勻強(qiáng)化，囊不強(qiáng)化 少見：實(shí)性腫塊 罕見：環(huán)狀強(qiáng)化的腫塊MRI表現(xiàn)T1WI：囊腫低信號(hào)，結(jié)節(jié)等信號(hào)T2WI：高信號(hào)部分病例出現(xiàn)明顯的流空效應(yīng);結(jié)節(jié)顯著強(qiáng)化DSA：大的乏血管腫塊

57、（囊腫）＋血管豐富的結(jié)節(jié)（有時(shí)見動(dòng)靜脈分流）,髓母細(xì)胞瘤,大體病理質(zhì)硬，邊界清或質(zhì)軟，邊界不清鏡下病理細(xì)胞密集，核圓或橢圓，胞質(zhì)稀少。分化不好的神經(jīng)外胚層細(xì)胞瘤細(xì)胞圍繞一神經(jīng)纖維作放射狀排列形成典型的菊型團(tuán)有絲分裂和細(xì)胞凋亡常見四種亞型：促纖維增生型，MB伴廣泛結(jié)節(jié)，大細(xì)胞型，黑色素型分期與分級(jí)：WHO Ⅳ級(jí)。,促纖維增生型MB,CT表現(xiàn)平掃：后顱凹中線的低密度實(shí)性腫塊。10％~20％伴鈣化。第四腦室向前移位增強(qiáng)：90

58、％以上強(qiáng)化。強(qiáng)化程度由輕度到中度,強(qiáng)化形式由斑片狀到均勻一致的強(qiáng)化MRI表現(xiàn)第四腦室中線處信號(hào)均勻的腫塊T1WI上等/低信號(hào)，T2WI等信號(hào)或低高混雜信號(hào)可見囊變，出血，壞死90％出現(xiàn)程度不同的強(qiáng)化50％可見腦脊液播散MRS ：NAA/Cho降低，Cr/Cho降低,Frost et al. medulloblastomas have a lateral location in 30% of cases inadults

59、 and 7% in children.Sarkar et al. lateral location was more common in adults (46.4%) as compared to childhood cases(10.7%),Frost JP, et al. Medulloblastoma in adults. Int J Radiat Oncol Biol Phys 1995;32:951–7.Sarkar

60、 C, et al. Are childhood and adult medulloblastoma different? A comparative study of clinicopathological features, proliferation index and apoptotic index. J Neuroncol 2002;59:49–61.,The classic well-defined homogeneous

61、vermian tumour with intense contrast enhancement seems to be rare in adults, whose tumours are predominantly in the cerebellar hemisphere, poorly defined and enhance less,Malheiros SM, Carrete Jr H, Stavale JN, et al. MR

62、I of medulloblastoma in adults. Neuroradiology 2003;45:463–7.,CPA medulloblastomas are rare and only 19 cases have been reported thus far. Most of the reported cases were adults, ranging between 19 and 46 yearsTherefore

63、, from the viewpoint of a differential diagnosis, the most important factor is to bear in mind the possibility of a CPA medulloblastoma,Awadhesh K, et al.Cerebellopointine angle medulloblastoma. Journal of Clinical Neuro

64、science (2004) 11(1), 42–45,原發(fā)腦淋巴瘤,98％是B細(xì)胞淋巴瘤，T細(xì)胞罕見；90％在幕上，局限性多于浸潤(rùn)性。20％~25％為多發(fā)病變大體病理大腦半球的單發(fā)或多發(fā)病變。中心有壞死，HIV陽性病人伴出血鏡下病理以血管為中心，環(huán)繞、浸潤(rùn)血管及血管周圍間隙。有幾種亞型，其中大細(xì)胞型占近50％，核漿質(zhì)比例升高,CT表現(xiàn)平掃：低密度，偶爾等密度?？沙鲅瑝乃涝鰪?qiáng)：常見中度均勻強(qiáng)化；少見環(huán)狀強(qiáng)化

65、 罕見：不強(qiáng)化（浸潤(rùn)性，與白質(zhì)腦病相仿）MRI表現(xiàn)T1WI及T2WI均為與皮質(zhì)等或低信號(hào)FLAIR上為高信號(hào)顯著均勻強(qiáng)化DWI：彌散受限MRS：NAA降低，Cho升高，可出現(xiàn)脂峰或乳酸峰,Deep location explains that seizures are less frequent than in other brain tumoursCT scans and MRI typically show i

66、n a third of cases unique or multiple periventricular, homogeneously enhancing lesions Ring-like enhancement is rare in immunocompetent patients, but atypical features can simulate inflammatory or infectious diseases

67、or other brain tumours (meningiomas) Spontaneous (or steroid-induced) disappearance of lesions is classic, hence the term ghost tumours,Anthony Behin,et al. Primary brain tumours in adultsTHE LANCET ? Vol 361 ? January

68、 25, 2003,CT usually reveals single or multiple isodense or hypodense lesions with intense contrast enhancement in more than 90% of the cases, indicating either unifocal or multifocal disease with perifocal edema which i

69、s less prominent than edema in malignant glioma or metastases Neuroradiological gold standard of both diagnosis as well as monitoring therapy is MRI, which shows hypointense, frequently multiple enhancing lesions in T1w