1、123一、垂体病变v重点v第一部分:垂体解剖及其与邻近组织的关系v第二部分:垂体微腺瘤的影像学特点v第三部分:垂体大腺瘤的影像学特点第一部分:蝶鞍垂体窝内,卵圆形小体,重量不到蝶鞍垂体窝内,卵圆形小体,重量不到1g,女性较大,外包坚韧的硬脑膜。女性较大,外包坚韧的硬脑膜。蝶鞍:深径蝶鞍:深径7-14mm 前后前后8-16mm 个头小,作用大:代谢、生长、发育和生殖个头小,作用大:代谢、生长、发育和生殖等等 垂体及鞍区的解剖 腺垂体(生长激素、催乳素、促甲状腺 激素、促肾上腺皮质激素、促性腺激素)垂体 神经垂体(催产素、抗利尿激素)v血供丰富明显均匀强化v腺垂体主要由大脑基底动脉发出的垂体上动脉
2、供应v神经部的血管主要来自左右颈内动脉发出的垂体下动脉结构及邻近组织关系3-III,4-IV,5-V,6-VI16-V2the optic chiasm(OC)垂体检查方式-MRvMR矢状位及冠状位 薄层扫描(最佳最佳)v增强扫描 动态增强腺垂体高度v婴幼儿:6mmv男性及绝经女性:8mmv青春期:10mmv孕产期:12mm正常T1FlairT2Flair青春期垂体垂体瘤垂体瘤 pituitary adenomav垂体腺瘤:源于垂体前叶垂体腺瘤:源于垂体前叶 系脑外肿瘤系脑外肿瘤 约占颅内肿瘤的约占颅内肿瘤的10%v垂体腺瘤:微腺瘤(垂体腺瘤:微腺瘤(10mm););大腺瘤(大腺瘤(10mm)
3、;);功能性腺瘤;功能性腺瘤;非功能性腺瘤;非功能性腺瘤;侵袭和非侵袭性侵袭和非侵袭性垂体腺瘤的临床表现垂体微腺瘤Microadenomav直径10mmv泌乳细胞腺瘤 PRLv生长激素细胞腺瘤 GHv促皮质腺瘤 ACTHv促性腺激素腺瘤 FSH and LHv促甲状腺素腺瘤 TSHv多激素腺瘤混合生长激素和泌乳细胞腺瘤MR征象MRI 直接征象:首选薄层冠扫CvT1低信号vT2信号不定,低信号-等信号v+C弱强化,极少为多发小灶微腺瘤,增强晚期微腺瘤呈高信号 MRI 间接征象:v垂体柄移位v垂体高度增加、垂体外形上缘局部隆起v垂体外缘局部隆起-压迫、推移海绵窦或颈动脉v鞍底局限下陷或局限骨质吸收
4、垂体微腺瘤的影像学表现低信号垂体微腺瘤的影像学表现垂体高度增加,上缘膨隆垂体微腺瘤的影像学表现鞍底局限性下陷或骨质吸收垂体微腺瘤的影像学表现垂体柄移位 F 27Y 闭经溢乳PRL增高小结:直接征象:小 低 弱 间接征象:中 上 下 外macroadenoma大腺瘤的临床表大腺瘤的临床表现现1.占位病变的扩张作用占位病变的扩张作用v鞍膈 头痛v视神经交叉 视力减退 视野缺损v下丘脑 尿崩症 睡眠 食欲 性格改变v脑神经 睑下垂 复视临临 床床 表表 现现2.激素的异常分泌激素的异常分泌v 或分泌过多v 或肿瘤增大压迫正常垂体组织而使 激素分泌减少垂体大腺瘤的影像学表现X线表现:蝶鞍扩大,前后床突
5、骨质吸收破坏,鞍底下陷前后径:8-16mm深径:7-14mmMacroadenoma垂体大腺瘤MRI直接征象:Mass-圆形/类圆形/不规则形,可出血坏死,密度信号不均匀;雪人征 增强均匀或不均匀强化MRI间接征象:v占位效应:突向鞍上池,视交叉、垂体柄移位v垂体向两侧生长-压迫、推移/包绕海绵窦或颈动脉v鞍底局限下陷或局限骨质吸收、破坏。直径10mm 垂体大腺瘤的影像学表现肿瘤侵犯破坏周围结构通过鞍隔 雪人征视交叉、鞍上池受压海绵窦闭塞包绕颈内动脉鞍底下陷侵犯蝶窦垂体大腺瘤的影像学表现垂体大腺瘤的影像学表现肿瘤侵犯破坏周围结构MR雪人征 MRT1WIT2WI+CT1WIT2WIv +CMRA
6、卒中+c诊断与鉴别诊断小结v直接征象:鞍区大的结节肿块;雪人征;坏死出血;多不均匀强化v间接征象:向上-鞍上池、视交叉、垂体柄 向下-鞍底 蝶鞍 向外-海绵窦、颈内动脉、脑神经v鉴别诊断:颅咽管瘤甲状腺病变的影像表现the thyroid superior glandsinferior glandsparathyroid glandsthyroid gland本节学习要点:本节学习要点:熟悉甲状腺正常影像解剖熟悉甲状腺正常影像解剖掌握甲状腺腺瘤、甲状腺癌影像诊断掌握甲状腺腺瘤、甲状腺癌影像诊断 (CT&MRI)解剖v2个侧叶+峡部v甲状软骨下方,气管旁,下级平第5-6气管软骨v侧叶2CMX4C
7、Mv有纤维囊包裹vCT 值可达值可达140 HU,注射造影剂后显著增强注射造影剂后显著增强贵阳医学院附属医院贵阳医学院附属医院CT室室正正常常甲甲状状腺腺CT解剖甲状腺基本病变的影像学改变弥漫性甲状腺增大 单纯甲状腺肿(非毒性甲状腺肿)毒性甲状腺肿 是具有甲状腺毒症的甲状腺肿 甲状腺炎:急性、亚急性、慢性 桥本氏病局限性增大 单发结节性:甲状腺肿瘤(腺瘤、腺癌)多发结节性甲状腺囊肿 单纯性囊肿 甲状舌管囊肿 异位甲状腺弥漫性甲状腺增大-桥本病Hashimoto Thyroiditisv1912年日本的桥本(Hashimoto)首先介绍慢性淋巴细胞性甲状腺炎,因而得名桥本病。v占甲状腺疾病的22
8、.5%,常发生于30-50岁的中年妇女;有明显的种族差异性。v常伴甲减桥本氏病CT/MRv甲状腺弥漫性对称性肿大,边清锐利v密度/信号较均匀,比正常甲状腺密度明显减低v不均匀强化,腺体边缘完整清晰vT1为等信号/低信号,T2为高信号,其间有粗低信号,可有/无扩张的血管v桥本甲状腺炎Hashimotos thyroiditis桥本甲状腺炎又慢性淋巴细胞性甲状腺炎小结:v对称弥漫肿大v均匀明显低密度v不均匀轻度强化v轮廓锐利单纯性甲状腺肿单纯性甲状腺肿临床:临床:女性多见,约女性多见,约 1:4 6,起病,起病缓慢。高代谢症群、甲状腺肿和缓慢。高代谢症群、甲状腺肿和突眼为典型表现。碘摄入不足。突眼
9、为典型表现。碘摄入不足。贵阳医学院附属医院贵阳医学院附属医院CT室室 单纯性甲状腺肿是由于甲状腺激素合成单纯性甲状腺肿是由于甲状腺激素合成障碍而引起的甲状腺组织代偿性增生肿大,障碍而引起的甲状腺组织代偿性增生肿大,在未出现结节时称为弥漫性增生性甲状腺在未出现结节时称为弥漫性增生性甲状腺肿肿(单纯性甲状腺肿单纯性甲状腺肿);当出现两个以上结节时称为多发性结节性当出现两个以上结节时称为多发性结节性甲状腺肿。甲状腺肿。甲状腺肿影像学表现 CT/MRv单纯甲状腺肿(少见):对称弥漫/肿大 密度减低且较均匀 包膜连续完整 增强后呈轻中度强化v多结节性甲状腺肿:非对称性增大,边清呈波浪状,轮廓完整 内见多
10、个散在的边清的低密度结节,结节无包膜 增强后有不同形式强化,有囊性结节、实性结节及囊实性混合结节,实性部分强化,囊性部分不强化。内可见斑片、斑点状粗钙化 不侵犯周围结构,颈部淋巴结肿大少见 1/3的肿物可向下延伸至上纵膈结节性甲状腺肿结节性甲状腺肿vthe diffuse enlargement of the thyroid结节性甲肿goiter extending to into the superior mediastinal 结节性甲肿goiter extending to into the superior mediastinal 格氏眼病(Graves diease)CT:眼外肌肌腹
11、增大、粗,多为双侧;顺序:内、下、外、上眼球突出MRI:眼外肌增粗眼球突(3)肌锥内脂肪间隙水肿甲状腺腺瘤adenomav是最常见的甲状腺良性肿瘤v有完整的包膜v青年女性多见甲状腺腺瘤-CTv圆/类圆形、界清、均匀低密度影v部分可坏死、囊变或钙化而呈混杂密度v增强:实性部分明显均匀强化,但程度低于周围正常的甲状腺组织,病灶边缘更加清晰,囊变或坏死区不强化。MRIv甲状腺内见边界清楚、轮廓规则的结节v其信号强度在T1加权像(T1WI)上与正常甲状腺组织相比呈中、低信号v在T2 加权像(T2WI)上为高信号v可见到完整的低信号晕环(包膜)v若有出血、囊变则信号不均匀甲状腺腺瘤甲状腺腺瘤贵阳医学院附
12、属医院贵阳医学院附属医院CT室室甲甲状状腺腺腺腺瘤瘤甲状腺腺瘤腺瘤恶性肿瘤malignantv甲状腺癌v甲状腺癌(thyroid carcinoma)是最常见的甲状腺恶性肿瘤,占全身恶性肿瘤的1%.甲状腺癌-恶性征象v1.US-微钙化.2.增强扫描,病灶呈浸润性生长,使受侵腺体边缘不规则,边缘连线中断,呈“节段缺损征”;增强环不完整,呈“强化残圈征”,为癌细胞侵及或穿透甲状腺包膜或肿瘤包膜所致。v3.结节/肿块边界不清v4.突出包膜,包膜分界不清v5.颈部淋巴结增多,肿大或钙化转移v6.累及周围结构v7.远处转移右侧甲状腺乳头状CA右侧甲状腺乳头状CA转移甲状腺乳头状CA思考题v腺瘤与甲癌的D
13、Dv甲癌与结节样增生的DD甲状旁腺superior glandsinferior glandsparathyroid glandsthyroid gland甲状旁腺功能亢进-自学甲状旁腺亢进 甲状旁腺瘤 甲状旁腺增生肥大v大小 5 x 3 x 1 mm;重约 40 and 50 mg.甲旁腺异位甲状旁腺瘤v adenoma-Parathyroid Adenomas v骨质疏松 病理性骨折骨膜下骨质吸收subperiosteum 棕色瘤v甲旁亢/减颅内表现v对称基底节钙化-DDX见对称基底节钙化Adrenal Disease肾上腺病变肾上腺的解剖v腹膜后 肾上方 肾筋膜内v分皮质和髓质 肾上腺的
14、形态:人,倒Y,倒 V正常肾上腺CT、MRI表现大小,形态、变异v右侧肾上腺呈线状,或倒Y形v左侧肾上腺呈三角形,或倒Y形v正常肾上腺2-6mm厚,2-4 cm长肾上腺的大小:1、粗细5cm 可7-10cm、分叶状、不规则v密度不均、常有坏死出血囊变偶有钙化v肾上腺肿块T1呈低信号或等信号、T2呈高信号,少数坏死、出血、囊变、钙化而信号不均v增强后明显不均匀强化v肿块粘连、包埋主动脉、下腔静脉v腹膜后淋巴结大v远处转移v皮质腺癌生长较快,可伴有发热、血沉快等vCT of a large inhomogeneous ACC of the left adrenal gland with multi
15、ple pulmonary and hepatic metastases v1A Left adrenocortical carcinoma in 54-year-old woman.Axial contrast-enhanced CT images show attenuation value measured with region of interest(oval)over uniformly enhanced solid component of lesion to avoid lateral necrotic low-attenuation component.Dev=deviati
16、on.Portal venous phase.vB.Axial delayed contrast-enhanced CT image at same level as A.Uniformly enhancing solid component shows minimal washout consistent with malignancy.adrenocortical carcinomathe relative percentage of enhancement loss is 15%.v(a)Nonenhanced scan obtained at level of middle porti
17、on of right adrenal gland shows well-defined mass(arrows)with isoattenuation relative to kidney parenchyma.(b,c)Contrast-enhanced scans obtained at same level as in a.The tumor(arrows)has heterogeneous enhancement on both(b)the 1-minute scan and(c)the 10-minute scan.Tumor attenuation is 41 HU in a,8
18、8 HU in b,and 75 HU in c.Thus,the absolute percentage of enhancement loss in this tumor is 28%,and the relative percentage of enhancement loss is 15%.vFigure 8a vPrimary adrenocortical carcinoma in a 55-year-old woman.Coronal volume-rendered images from contrast-enhanced CT show a nearly 15-cm right
19、 adrenal mass that displaces the right kidney inferolaterally and invades the inferior vena cava(IVC)medially(arrowheads in a).Tumor thrombus extends into the intrahepatic IVC(arrows in b).adrenocortical carcinomavFigure 14b.(a,b)Sagittal T1-weighted three-dimensional contrast-enhanced GRE MR image
20、obtained with VIBE(a)and coronal T2-weighted MR image obtained with half-Fourier RARE(b)show a large mass involving the right adrenal gland.The mass exhibits heterogeneous low signal intensity on the T1-weighted image and high signal intensity with a heterogeneous pattern of contrast enhancement and
21、 areas of necrosis(arrow in b)on the T2-weighted image.(c)Photograph of the specimen shows a yellow and red tumor with large areas of necrosis,findings typical of adrenocortical carcinoma.Malignant pheochromocytoma vMalignant pheochromocytoma in a 62-year-old man.(a)Contrast-enhanced CT scan shows a
22、 complex left adrenal mass(solid arrows)representing a malignant pheochromocytoma with hepatic metastases(open arrow)and portocaval adenopathy.(b)Pelvic CT scan shows sacral and left iliac bone metastases(arrow).Metastatic spread is the only reliable criterion for differentiating a benign from a mal
23、ignant pheochromocytoma.小结:良恶性肾上腺肿瘤鉴别恶性-肿块肿块呈分叶形,形态不规则;边缘模糊,与周围器官粘连;肿块直径5cm;增长快 转移良性-smooth margins D5CM homogeneous density肾上腺TB-自学v肾上腺TB多双肾上腺累及v肺TB,或全身TBv功能减退CT/MR findingsv无特异性v双侧肿块 v囊变v环形强化vMR 干酪样坏死 短T2 v钙化vFigure 24.Addison disease in a 51-year-old man.Contrast-enhanced CT scan shows both adren
24、al glands,which appear small and with dense calcification.The cause of the calcification was not known but may have been due to remote hemorrhage or tuberculosis.TBSimple CystsvCT-水样密度,壁薄边清vMR-长T1长T2,界清,无强化,少有出血vFigure 7b.(a,b)Coronal T1-weighted in-phase(a)and T2-weighted half-Fourier RARE(b)MR ima
25、ges show an oval,well-circumscribed,right adrenal cyst(arrow in b)with a thin wall(arrowhead in b).The cyst has a typical appearance,showing low signal intensity at T1-weighted imaging and high signal intensity at T2-weighted imaging.(c)Photomicrograph(original magnification,100;H-E stain)shows a cystic lesion with a simple cuboidal mesothelial lining.