朗读老师：医院
翻译老师：医院放射科
审校老师：姜春医院
History:A43-year-oldmanwithnosignificantmedicalhistorywasreferredforthreeweeksofrightfacialweaknessthatprogressedtoincluderightarmandhandweakness,rightlegweakness,andword-findingdifficulty.Priortoreferral,aCTscanintheemergencydepartmentdemonstratedamass-likelesion.
MRbrainandMRspectroscopy(MRS)scanswithdiffusion-tensorimaging(DTI)werealsoperformed.Clickontheimagebelowtoenlarge.
病史：男性，43岁，主诉三个星期前无明显诱因出现右侧面肌无力，后进展为右侧上肢、下肢无力，唤词困难。急诊CT发现颅内肿瘤样病变。
头颅MR、MRS及DTI扫描图像如下
Findingsanddiagnosis·MRbrain:DiffuseexpansilelesionwithT2/FLAIRhyperintensitywithpatchymultifocalenhancementextendingfromtheleftcoronaradiatathroughtheposteriorlimboftheleftinternalcapsule,leftthalamus,leftcerebralpeduncle,thepons,andleftcerebellarpeduncle,andintothemedullaoblongata.
·MRS:Single-voxelMRspectroscopyofafocalabnormalareaintheleftcerebralpedunclewithechotime(TE)ofmsecdemonstrateselevatedcholinepeaks(3.2ppm)withdepressedNAA(2.0ppm)andcreatine(2.0ppm)peaks.
·DTI:Color-encodedstructuralorientationmapofthefibertractsshowssignificantlossofthenormaldirectionalencodedcoloroftheposteriorlimboftheleftinternalcapsule.Correspondingfractionalanisotropy(FA)mapshowsindistinctnessandreducedsignalintensityofthefibersoftheposteriorlimb.Findingsarehighlysuggestiveoftumoralinfiltrationandlikelydisruptionofthecorticalspinaltract.
影像与诊断
颅脑MR：左侧放射冠、内囊后肢、丘脑、大脑脚、桥脑、小脑脚及延髓见弥漫性膨胀性病变，T2/FLAIR呈高信号，增强呈不均匀多灶性斑片状强化。
MRS：选择左侧大脑脚病变中心位置，回波时间ms，显示胆碱峰升高（3.2ppm），NAA（2.0ppm）和Cr(2.0ppm）峰下降。
DTI（弥散张量成像）：彩色纤维束结构成像显示左侧内囊后肢正常的定向编码色显著消失。内囊后肢纤维束在相对应的各向异性分数图上显示模糊、信号强度减低。图像高度提示肿瘤浸润以及皮质脊髓束可能中断。
Differentialdiagnosis
·Glioma
·Cerebralmetastasis
·Tumefactivedemyelination
·Subacutecerebralinfarct
Diagnosis:Glioma-anaplasticastrocytoma
鉴别诊断
胶质瘤
脑内转移瘤
肿瘤样脱髓鞘病变
亚急性脑梗死
诊断：胶质瘤-间变型星形细胞瘤
Pathophysiology
Anaplasticastrocytoma(AA)isamalignant,diffuselyinfiltratingneuroepithelialtumororiginatingfromtheastrocytesofthecentralnervoussystem(CNS).AccordingtotheWorldHealthOrganization(WHO)classificationsystemforglialtumors,itisahigh-gradetumor(gradeIII/IV)characterizedbyhypercellularity,mitoticactivity,andnuclearatypiawithoutnecrosis.Twenty-fivepercentofAAsarisedenovo,while75%resultfromtransformationoflower-gradeastrocytoma.MalignantprogressionofAAmayresultinglioblastomamultiforme(WHOgradeIV/IV).Exposuretoionizingradiation,particularlyatayoungage,aswellasrareMendeliandisordersincludingneurofibromatosistypes1and2,tuberoussclerosis,andLi-Fraumenisyndromearetheonlywell-establishedriskfactorsforthedevelopmentofAA.
病理生理
间变型星形细胞瘤（AA）是一种来源于中枢神经系统星形细胞的神经上皮肿瘤，具有恶性、弥漫浸润特性。根据WHO胶质瘤分型，AA属于高级别肿瘤（III/IV级），具有细胞密集，核分裂活跃，核异型性无坏死的特点。25%的AA属于原发，75%由低级别星形细胞瘤演变而来。AA有恶变为多形性胶质母细胞瘤（IV/IV级）的可能。AA致病的危险因素，目前已经明确的有低龄电离辐射，罕见的遗传性疾病，例如神经纤维瘤病1,2型、结节性硬化、李-佛美尼综合症。
Epidemiology
AAisun
转载请注明地址:http://www.ihgqp.com/kfbl/17504.html
