胸腺瘤的CT和平片分析

目的　探讨胸腺瘤的X线与CT诊断价值。方法　分析 30例经手术病理证实的胸腺瘤X线和CT表现 ,并与病理对照。结果　 18例非侵袭性胸腺瘤 ,胸片仅发现 15例 ,CT扫描 10例 ,均为前纵隔软组织肿块 ,边界清楚 ,密度均匀。 12例侵袭性胸腺瘤 ,肿瘤侵犯邻近器官 ,CT显示纵隔胸膜受侵 3例 ,心包受侵 2例 ,大血管结构受侵 2例 ,胸膜种植 3例 ,胸腔积液 2例 ,腹腔受侵和纵隔淋巴结转移各 1例 ;胸片仅能显示 1例肿瘤侵犯纵隔胸膜和 1例胸膜种植。结论　CT扫描在胸腺瘤的发现和判别侵袭性方面明显优于X线平片并且是可靠预测胸腺瘤侵袭性的检查方法。     

侵袭性胸腺瘤与非侵袭性胸腺瘤的CT诊断与鉴别

目的：用多层螺旋CT扫描诊断胸腺瘤并评价其侵袭性。资料与方法：对CT诊断为胸腺瘤并经手术病理证实的23个病例进行对照分析。结果：胸腺瘤为前纵膈内类圆形或不规则的软组织肿块，其有否侵袭性主要取决于是否侵犯胸膜，是否累及邻近结构。结论：多层螺旋CT对胸腺瘤的诊断及对其侵袭性的评价有较高价值。     

恶性胸腺瘤的CT与MRI诊断

目的：分析侵袭性胸腺瘤及胸腺癌的CT及MRI表现，探讨其鉴别诊断要点。方法：复习经病理组织学证实的18例侵袭性胸腺瘤及9例胸腺癌的CT、MRI所见，重点观察肿瘤的大小、密度、边缘改变，对周围纵隔结构的侵犯。结果：18例侵袭性胸腺瘤、9例胸腺癌CT、MRI均表现为前纵隔不规则软组织肿块。前者肿瘤直径大于8cm者15例（83％），病灶内密度及信号不均匀12例。心血管受侵16例，后者肿块直径在8cm以上者7例（77.8％),肿块内密度及信号不均6例，心知管受累8例，纵隔肺门淋巴结转移1例，肺内转移3例，双侧肾上腺及肝脏转移1例。结论：虽然侵袭性胸腺瘤和胸腺癌的影像学表现相似，但胸腺癌更具有侵袭性，胸外转移常见，病理组织学检查有助于两者的鉴别。     

儿童胸腺区恶性肿瘤的CT表现及其鉴别

目的分析儿童胸腺区恶性肿瘤的CT表现。资料与方法对8例经病理证实的儿童胸腺区恶性肿瘤的CT表现进行研究。结果8例均表现为胸腺区不均匀软组织密度肿块。3例侵袭性胸腺瘤，其中2例伴有胸腔积液，l例伴有肝脏转移。3例淋巴瘤胸腺浸润，均伴有其他部位淋巴结增大，l例伴有胸腔积液，2例伴有胸壁浸润以及椎管内侵犯l例。2例恶性生殖细胞瘤，其中l例恶性畸胎瘤肿块内见斑点状钙化灶，l例卵黄囊瘤伴有胸膜不规则增厚。结论CT检查能准确地显示出胸腺区恶性肿瘤的内部特征及其对邻近脏器的侵犯，因而对儿童胸腺区恶性肿瘤的诊断及鉴别诊断有较大价值。     

纵隔胸腺瘤和淋巴瘤的影像特征及鉴别诊断(附65例分析)

目的探讨纵隔胸腺瘤和淋巴瘤的影像特征和鉴别诊断,以提高诊断正确率。方法回顾分析65例经手术、病理证实的纵隔胸腺瘤和淋巴瘤的CT和X线表现,其中胸腺瘤25例(非侵袭性胸腺瘤13例,侵袭性胸腺瘤12例),淋巴瘤40例(NHL 28例,HD 12例);均有X线和CT影像,2例做了MR I检查。结果胸腺瘤多局限于前纵隔或延伸至中纵隔,肿块多偏向纵隔一侧(14/25,56%),邻近血管结构多受推移(16/25,64%);本组均未见浅表淋巴结肿大;而侵袭性胸腺瘤(9/12,75%)较非侵袭性胸腺瘤(5/13,38%)有明显分叶,其中多数侵袭性胸腺瘤(8/12,67%)边缘见小结节样突起;侵袭性胸腺瘤坏死囊变率(9/12,75%)高于非侵袭性胸腺瘤(4/13,31%)。纵隔淋巴瘤大多数(32/40,80%)累及胸部多组淋巴结,其中合并腋窝淋巴结肿大(10/40,25%);肿块多向纵隔两侧生长(24/40,60%);病灶呈多发结节或HRCT可分辨的结节融合肿块(21/40,52.5%),淋巴瘤包埋周围血管结构(25/40,62.5%)多于胸腺瘤(2/25,8%),结节或肿块坏死率(10/40,25%)低于胸腺瘤(13/25,52%);淋巴瘤发病年龄轻(≤40岁28/40,75%),而胸腺瘤发病年龄多>40岁(16/25,64%)。结论纵隔胸腺瘤和淋巴瘤各自具有一定的影像特征,根据其影像表现并结合临床,能够做出正确的诊断。     

侵袭性胸腺瘤CT表现与诊断价值

目的 探讨侵袭性胸腺瘤CT表现特征.方法 经病理证实的15例侵袭性胸腺瘤均行CT平扫加增强检查,分别对病变的形态、密度、强化方式、周围结构侵犯及种植情况进行回顾性分析.结果 15例肿瘤均表现为边缘分叶、不规则,密度不均,平扫CT值40～50HU,其中坏死囊变11例,点状钙化4例;15例均有纵隔结构侵犯,周围脂肪间隙模糊、消失,其中大血管侵犯9例,心包侵犯（心包积液）5例,胸膜肺界面不清8例,胸腔积液6例;增强扫描见肿瘤实质部分呈轻至中度强化,CT值增加10～20HU,坏死囊变不强化.结论 侵袭性胸腺瘤CT表现具有一定特征,螺旋CT能显示肿瘤内部改变,又能显示周围组织受侵犯情况,具有较高诊断价值.     

侵袭性胸腺瘤的CT表现及病理对照

目的：分析侵袭性胸腺瘤的CT表现，评价CT对其临床分期的准确性。资料与方法：回顾分析32例经手术病理证实的侵袭性胸腺瘤的CT所见，通过对病变的密度、周围纵隔结构的侵犯、胸膜肿植以及纵隔外转移情况的观察进行分期，并和病理分期进行比较。结果：侵袭性胸腺瘤的CT表现主要有：分叶状或不规则肿块；密度不均匀；局灶性钙化；邻近结构的脂肪层消失；侵及心包、胸膜、肺及其他器官。CT对临床分期判断准确性为87．5％，特异性为90％，敏感性为83．3％。结论：CT对侵袭性胸腺瘤术前分期及病变范围的显示准确，对确定手术方案，评价治疗效果及判断复发具有重要意义。     

胸腺瘤的MSCT与MRI诊断

目的: 探讨MSCT、MRI联合诊断胸腺瘤的价值.材料和方法: 回顾性分析36例经手术及病理证实的胸腺瘤的MSCT和20例MRI表现.结果: 36例中,MSCT诊断侵袭性胸腺瘤9例,MRI诊断侵袭性胸腺瘤13例(13/20),手术病理证实侵袭性胸腺瘤17例.结论: CT是检出和诊断胸腺瘤的较佳方法之一,如怀疑侵袭性胸腺瘤,MRI检查能更准确地观察肿瘤边缘的改变与邻近组织间的关系,较明显地提高诊断准确率.     

侵袭性胸腺瘤的CT诊断及评价

目的分析侵袭性胸腺瘤的ＣＴ表现以便于分期和计划治疗。材料与方法分析２６例手术及病理证实的侵袭性胸腺瘤的ＣＴ所见，着重观察病变的密度，对周围纵隔结构的侵犯、胸膜种植以及纵隔外转移情况。结果２６例侵袭性胸腺瘤ＣＴ均显示为前纵隔软组织肿块，１６例密度不均，肿块不规则侵犯邻近器官２４例，主要表现在纵隔胸膜受侵７例，肺受侵９例，胸膜种植３例，心血管结构受侵２０例，以及心膈角区和腹腔受侵３例。结论ＣＴ在显示胸膜、心包和肺实质侵犯方面极其有效，对病变范围可进行可靠的评价，常规ＣＴ扫描可进行准确的分期和决定治疗方案。     

螺旋CT对胸腺瘤的诊断及其临床价值

目的：通过螺旋CT(spiral CT，SCT)分析胸腺瘤的影像学表现并判断其良恶性的临床价值。方法：搜集经手术病理证实的胸腺瘤30例。其中非侵袭性胸腺瘤(noninvasive thymoma，NIT)即良性胸腺瘤22例，侵袭性胸腺瘤(invasive thymorrm，IT)即恶性胸腺瘤8例。通过SCT分析胸腺瘤的瘤体形态、密度、强化特点、肿块与纵膈结构关系等影像学表现，并与病理结果相对照，研究胸腺瘤良恶性即有无侵袭性的对应关系。结果：1、SC丁诊断NIT20例，其主要表现为前上纵膈内密度均匀的圆形或类圆形轻度强化的软组织肿块，与纵膈心脏大血管分界清晰。2、SCT诊断IT7例，主要表现为前中上纵膈内分叶状、不规则形软组织肿块，密度不均，强化不一且或伴有囊变坏死区，肿瘤与心脏大血管脂肪环破坏，心包积液、纵膈胸膜浸润以及上腔静脉受压变形等。结论：SCT对胸腺瘤的良恶性(即侵袭性)判断具有较高的准确性，为临床术前治疗方案的确定以及判断其预后具有较高的指导价值。     

侵袭性和非侵袭性胸腺瘤的CT鉴别诊断

目的 :评价CT对侵袭性和非侵袭性胸腺瘤的鉴别诊断价值。方法 :由两位放射科医师采用双盲法对 2 9例侵袭性胸腺瘤和 2 4例非侵袭性胸腺瘤进行单独评价 ,分析CT诊断侵袭性或非侵袭性胸腺瘤的可靠性 ,并与手术病理结果对照。结果 :侵袭性胸腺瘤 ( 2 1例 ,占 72 %)较非侵袭性胸腺瘤 ( 7例 ,占 2 9%)有明显的分叶 (P <0 .0 5 )。侵袭性胸腺瘤囊变率 ( 2 3例 ,占 79%)较非侵袭性胸腺瘤 ( 6例 ,占 2 3 %)高 (P <0 .0 1) ;侵袭性胸腺瘤增强后较非侵袭性胸腺瘤有明显强化。结论 :肿瘤边缘分叶或不规则、囊变或坏死、增强前后CT值相差 2 0HU、纵隔脂肪线消失等CT征象提示侵袭性胸腺瘤。     

MR imaging of thymoma--comparison with CT, operative, and pathological findings]

Twenty-six patients with thymoma, who had magnetic resonance (MR) imaging and computed tomography (CT) before surgery, were studied. Twenty-six thymomas were classified into 11 non-invasive thymomas (Masaoka's clinical stage I) and 15 invasive thymomas (stage II, III, and IV). On MR imaging compared with histological findings, low signal intensity rim of the tumor was corresponded to fibrous capsule of the tumor, and linear and/or reticular low signal intensity lines in the tumor were corresponded to the fibrous septae dividing thymoma into lobules. The detectability of these findings by MR imaging was superior to that by CT. Margin of the tumor was smooth in non-invasive thymoma rather than invasive thymoma. The diagnostic accuracy of invasion to vessel, and pleura or lung on MR imaging and CT was compared with operative and histological findings. MR imaging was same as CT in its ability to detect tumoral invasion to vessel, and slightly superior to pleura or lung. In conclusion MR images clearly show the findings corresponding to pathologic specimens, and MR imaging combining with CT is useful to differentiate non-invasive thymoma to invasive thymoma.     

Thymic lesions and myasthenia gravis. Diagnosis based on mediastinal imaging and pathological findings

Purpose:
To achieve a better understanding of the role of CT and MR imaging in the study of the mediastinum in patients with myasthenia gravis (MG). Material and Methods:
Mediastinal CT and MR findings were correlated with the histopathological results in 104 thymectomized MG patients. Results:
CT was performed in 104 patients; in 11 of them, MR was also carried out. 44 patients had hyperplasia at histology. On CT, thymic hyperplasia was confirmed in 16 cases, thymoma was diagnosed in 10 and a normal thymus in 18 (sensitivity 36%, specificity 95%). Of 52 patients with thymoma at histology, CT showed thymoma in 46, hyperplasia in 1, and normal thymus in 5. CT showed 88.5% sensitivity and 77% specificity for thymoma. In 10 patients with invasive thymoma, CT was indiscriminate, while invasiveness was detected in 7 cases at MR (70% sensitivity) and at CT in 1 case. Both CT and MR detected tumor recurrence in 5 cases, but the exact localization and degree of invasion were best defined by MR. Conclusion:
In MG patients CT is a sensitive, specific and efficient modality for detecting thymoma, but is less so for detecting thymic hyperplasia. MR was shown to be accurate in detecting invasive thymoma both preoperatively and in postoperative follow-up.     

胸腺瘤的螺旋CT诊断

目的：评价CT对胸腺瘤的诊断价值。方法：对43例经临床、手术、病理证实胸腺瘤的CT表现进行回顾性分析。结果：侵袭性胸腺瘤23例,形态不规则,边界欠清晰,有不同程度胸膜和／或心包膜增厚、受侵,其中15例内部密度不均匀,实质部分呈轻-中度强化。非侵袭性胸腺瘤20例,形态规则,边界清晰,内部密度均匀,实质部分呈轻度均匀强化。结论：CT检查对胸腺瘤有较高的诊断价值,对指导临床治疗有重要意义。     

胸腺瘤的X线平片、CT诊断(附23例分析)

目的:评价X线平片、CT对胸腺瘤的诊断价值。方法:回顾分析23例经手术病理证实的胸腺瘤的临床、X线、CT表现,将结果与病理进行对照分析。结果:非侵袭性胸腺瘤X线平片诊断符合率为66.7%,CT诊断符合率为86.7%。侵袭性胸腺瘤X线诊断符合率为25%,CT诊断符合率为87.5%。CT敏感性和特异性较胸片为高,尤其判断胸腺瘤是否具有“侵袭性”方面CT明显优于X线平片。结论:X线平片是诊断胸腺瘤的基本方法,CT是诊断胸腺瘤最有效的方法,二者可以互相结合。病理最终可确定组织来源和性质,CT是病理判断胸腺瘤是否具有“侵袭性”的重要补充。     

Imaging of an invasive malignant thymoma on PET Scan: CT and histopathologic correlation

Thymomas are common primary mediastinal neoplasms. They can be benign or malignant. The diagnosis of malignant thymomas is based on capsular invasion, cellular atypia and distant metastases. We present a case of invasive malignant thymoma as diagnosed on PET and CT scan with histologic correlation and review of literature. A seventy year old Asian man presented with cough and dyspnea. A CT scan showed an anterior mediastinal mass, and a PET scan showed a hypermetabolic mass in the corresponding location. Resection of the mass revealed a minimally invasive thymoma based on evidence of capsular invasion. PET scan proved invaluable in correctly diagnosing, staging the lesion, and excluding any extramediastinal involvement.