肋骨（及胸壁）的影像诊断课件

肋骨(及胸壁)的病变较少见，文献以个例报 道较多。俺这种老骨头有时也不知从何下口 ! 鉴于大家对马哥系列疑难病例不太感兴趣, 俺只有给弟兄们换换口味了! 本帖病例及图片来源于国内外专业杂志、书 籍及相关网站，俺就不一一注明。谨在此致 谢！ 欢迎大家跟帖丰富内容！ Rib Lesions 肋骨病变分类（俺已翻译成中文） - Rib tumor Primary Malignancy: chondrosarcoma, plasmacytoma, lymphoma, osteosarcoma, MFH Benign: osteochondroma, enchondroma, osteoblastoma, osteoid osteoma, chondroblastoma, hemangioma Metastasis, direct invasion - Infectious disease Osteomyelitis fungal, tuberculosis, actinomycosis, other bacteria - Others Fibrous dysplasia, Langerhans cell histiocytosis, Paget disease, renal osteodystrophy, hemoglobinopathies- 肋骨病变分类： 肋骨肿瘤 原发性 恶性：软骨肉瘤、浆细胞瘤、 淋巴瘤、骨肉瘤、MFH 良性：骨软骨瘤、软骨瘤、骨 母细胞瘤、骨样骨瘤、软骨母细 胞瘤、血管瘤 转移瘤，直接侵犯 感染性疾病 骨髓炎或脓肿、真菌性、结核 、放线菌（actinomycosis）、 其他细菌 其他 纤维结构不良、嗜酸性肉芽肿 、Pagets disease、肾性骨营 养不良、血红蛋白病 肋骨正常解剖和变异： 肋骨正常解剖： a：胸骨角水平 Rib counting at CT with the sternal angle as an anatomic landmark. Sequential axial chest CT scans of the ribs and sternum show identification of the sternal angle with the second costal cartilage and rib (2) followed by the counting of the third, fourth, and fifth ribs (35) in numeric order . The fifth rib is traced as the reference rib in sequential planes (bd). Note that the rib moves slightly anterior in the caudal planes. The target rib with the metastatic lesion (arrowhead in d) is identified by counting ribs in numeric order from fifth (5) to fourth (4) in the same axial plane. 肋骨正常解剖： b：剑突水平 Rib counting at CT with the xiphoid process as an anatomic landmark. Axial CT scan shows the xiphoid process , the seventh rib (7), and the relative position of the lower ribs (69). It is important to identify the transverse portion of the costal cartilage (arrows), at which point one stops counting down and starts counting up (ie, moves from medial to lateral). 5 = fifth rib. 肋骨正常解剖： c：肋骨伴随影 Rib companion shadows. Posteroanterior chest radiograph (magnified view) shows rib companion shadows projecting adjacent to the inferior and inferolateral margins of the second rib (arrows). Sagittal reformatted CT scan of the thorax shows the posterior or posterolateral portion of the second rib (2) located at the superoposterior aspect of the lung. Note the slightly protruding soft tissues in the second intercostal space (arrow), which may cause the rib companion shadow below the second rib. 1 = first rib, 3 = third rib, 4 = fourth rib. 肋骨正常解剖 d：血管沟 图1：Costal groove. Photograph of a right rib shows the normal anatomy of the costal groove (arrows). Radiograph of the same rib shows a thin, sharp hairline caused by the cortex of the costal groove (arrows).图2：Sharp lines along the lower costal margin. Posteroanterior chest radiograph shows sharp, thin lines along the lower margin of the ribs (arrows). 肋骨正常解剖 e。肋骨重叠影 图1：Rib overlying shadows. Posteroanterior chest radiograph shows two types of short, linear opacities projecting over the lateral portion of the ribs. White arrows indicate anterior overlying opacity, black arrow indicates posterior overlying opacity. 图2：Rib overlying shadows. Photograph of a right eighth rib shows a blue catheter along the superior margin and a guide wire along the inferomedial margin. Radiograph of the same rib shows the catheter (thick line) and the guide wire (thin line) crossing between the external and internal margins at the lateral portion of the rib. The course of the guide wire at the lateral portion of the rib is very similar to the medial border of the anterior overlying opacity. The course of the catheter corresponds to the posterior overlying opacity. Schematic demonstrates the relationship between the rib margins and the overlying opacities. The gray area corresponds to the overlying shadow, which results from overlap of the bone structure; the blue line indicates the superior margin of the rib; and the red line indicates the inferomedial margin of the rib. 肋骨变异 a.叉状肋： 图1：Forked rib with isolated cartilaginous segment in an asymptomatic 21-year- old man. Frontal chest radiograph shows a widened interspace between the right anterior fourth and fifth ribs with linear intercostal calcifications (arrow). 图2：Bifid (forked) rib. Posteroanterior chest radiograph (magnified view) shows a bifid or forked deformity of the anterior end of the fifth rib (* and white arrows). An associated spurlike process or incomplete fusion of the ribs (black arrow) is seen. 肋骨变异 b.颈肋 Cervical ribs in an asymptomatic patient. Frontal chest radiograph shows bilateral cervical ribs (arrowheads); the left one fuses anteriorly to the first rib (arrow). 肋骨变异 c：肋骨骨桥形成或融合 图1：Bone bridging in a 34-year-old woman with no history of fracture or trauma. Frontal chest radiograph shows a bone bridge joining the right anterior first and second ribs. Pseudoarticulation is also present (arrows). 图2：Fusion of the left third and fourth ribs in a 45-year-old man. Frontal chest radiograph shows close apposition of the posterior ribs (white arrow) and broad fusion of the anterior segments (black arrows). These findings represent a failure of normal segmentation. Vertebral anomalies may be found at the same level in some cases. 肋骨正常解剖和变异： 肋骨正常解剖和变异： 又找到1例肋骨变异(作为开胃菜送给 91616lyt兄及各位弟兄!) Anomalous articulation of the rib is almost always asymptomatic and found parenthetically on routine plain chest films. In 1944 Etter reviewed 40,000 consecutive roentgenograms and found 31 cases(1 in 1290, 0.078%) of anomalous first ribs that simulated an isolated fracture(1). In 1945 Bowie and Jacobson reviewed 62,782 roentgenographic chest examinations and found 17 cases(1 in 3692, 0.027%) of anomalous articulation of the first rib(2). Anomalous articulation forms a calluslike change and pseudoarthrosis, which is often mistaken for an old, unhealed fracture. Pseudoarthrosis not caused by fracture is believed to develop from one center of ossification that progressed into two centers. A permanent gap between the ribs may remain. This may sometimes be palpated as hard, fixed mass in supraclavicular fossa and thus mistaken for supraclavicular neoplasia. The most commonly encountered tumors of the ribs are metastatic lesions. Primary tumors of the ribs are less common and about two-thirds of the primary tumors are malignant. The primary tumors of the ribs occur in descending order of frequency as follows: Chondrosarcoma 30%, Lymphoma, Myeloma (multiple or solitary) 17%, Fibrous dysplasia 12%, Osteosarcoma 10%, Osteochondroma 8%, Ewings sarcoma 6%, Eosinophilic granuloma 3%, and numerous rare tumors (Hemangioma, Mesenchymal chondrosarcoma, Primitive neuroectodermal tumor in infancy, Parosteal chondroma, Chondroblastoma, Chondromyxoid fibroma, Giant cell tumor, Giant cell tumor of Pagets disease, Giant cell tumor of hyperparathyroidism, Nonossifying fibroma, Fibrous histiocytoma, Osteoid osteoma, Osteoblastoma, Aneurysmal bone cyst, fibrosarcoma, and angiosarcoma). 肋骨最常见的肿瘤是转移瘤 ，原发肿瘤较少见，约2/3的 原发肿瘤为恶性。其发病率 如下：软骨肉瘤30%、淋巴瘤 及骨髓瘤（多发或单发）各 17%、纤维结构不良12%、骨 肉瘤10%、骨软骨瘤8%、 Ewings瘤6%、嗜酸性肉芽 肿3%、其他少见肿瘤（血管 瘤、间质软骨肉瘤、婴幼儿 的原始神经上皮细胞瘤、骨 旁软骨瘤、软骨母细胞瘤、 软骨黏液样纤维瘤、巨细胞 瘤、Pagets disease的巨 细胞瘤样改变、甲旁亢的棕 色瘤、非骨化性纤维瘤、纤 维组织细胞瘤、骨样骨瘤、 骨母细胞瘤、动脉瘤样骨囊 肿、纤维肉瘤、血管肉瘤等 ） 以下俺基本按这个顺序开讲 ： 1.肋骨转移瘤 肋骨是转移瘤的好发部位之一，x线检查 骨转移敏感性低，ECT检测骨转移敏感性 高，但特异性低。MRI显示早期骨髓浸润 优于CT，但肋骨转移瘤MR信号缺乏特异性 。CT可显示骨小梁和骨皮质破坏及周围软 组织、肺组织受侵等，在显示骨皮质破坏 、成骨和混合型转移方面优于MRI。 全身各部位恶性肿瘤均可转移到肋骨。以 肺癌、乳腺癌、肝癌多见，尤其肺癌占46 。转移灶通过破骨和成骨活动进行骨的 重建，由于二者的相对程度不同，形成骨 转移类型的差异。肋骨转移瘤的CT表现可 分为溶骨型、成骨型和混合型。溶骨型肋 骨转移瘤多见，混合型、成骨型少见，后 者多系生长缓慢的肿瘤所引起，如肺癌、 乳腺癌、前列腺癌、膀胱癌等。 除常见的与转移瘤有关的解剖和病理生理 特点外，肺癌细胞还可直接蔓延到肋骨， 故肋骨是肺癌骨转移的好发部位。各型肺 癌肋骨转移均以溶骨型为多，成骨型转移 以腺癌多见，混合型可见于鳞癌。肺癌的 肋骨转移可能与其组织类型、分化程度、 癌灶大小、病灶部位和病程等多因素有关 。 肋骨转移瘤应与骨肉瘤进行鉴别，前者多 见于老年人，软组织肿块较小、不明显或 无软组织肿块(成骨性转移瘤)，无骨膜反 应。 肋骨溶骨型转移瘤 肋骨成骨型转移瘤 2.肋骨软骨肉瘤 肋骨软骨肉瘤好发于年龄较 大的患者，CT表现为肋骨局 限性骨质破坏，可伴有特征 性的圆形、弧形或结节状软 骨钙化，软组织肿块常较小 ，较大者可见低密度的坏死 、囊变区。无钙化灶的软骨 肉瘤应与转移瘤、淋巴瘤和 骨髓瘤鉴别，后三者通常为 多骨、多灶性浸润，单发病 灶的鉴别诊断依赖于病理活 检。 3.肋骨淋巴瘤 Skeletal Involvement of Hodgkins Disease - 10-25% of cases of HD - infrequent at the time of clinical presentation - more common in adultchild - Pain is the most common symptom - hematogenous or direct spread from LN - Prognosis : depends on histologic type - common site: spine, pelvis, rib, femur, sternum, scapula - multiple lesion (2/3) solitary form - Osteolytic (75%), Osteosclerotic (15%), mixed (10%) * diffuse sclerosis of vertebral body ( ivory vertebra ) : similar skeletal metastasis, Pagets disease Hodgkins Disease的骨骼改变 10-25%的Hodgkins Disease侵犯骨骼 临床上呈散发病例。 成人比儿童常见 疼痛是最常见的症状 预后与组织学类型有关 好发部位：脊柱、骨盆、肋骨、股骨、胸骨 、肩胛骨 多发病灶（占2/3）多于单发病灶 溶骨型（75%）、成骨型（15%）、混合型（ 10%） *椎体弥散性硬化（象牙椎）与转移瘤、Pagets disease相似 肋骨淋巴瘤文摘：溶骨、膨胀、局部骨硬化、软组织肿块范围较 骨破坏范围大 4.肋骨骨髓瘤（多发或单发） Thoracic involvement in multiple myeloma is common. Skeletal or pleuropulmonary abnormalities were 46% in one review of 958 patients and radiologic abnormalities were in 25% at the time of diagnosis. The most common manifestation of thoracic disease is neoplastic infiltration of the skeleton. The most frequently affected site is the ribs showing focal expansion with extension and proliferation of tumor in the adjacent chest wall, although involvement of the vertebrae and sternum. The radiographic findings usually consist of one or more well-defined osteolytic lesions, osteoporosis, fractures, or a combination of lesions. In the involved rib, a smooth homogenous soft issue mass protruding into thorax and compressing the lung is a typical radiologic appearance. The tumor masses can grow to a larger size, sometimes almost completely opacifying a hemithorax. However, a similar appearance can be seen in association with a primary pulmonary disease such as pulmonary carcinoma or fungal infection that invade the chest wall, with primary or metastatic chest wall neoplasm, and with other primary chest wall disease such as osteomyelitis. Pleuropulmonary involvement is much less common. Rarely, malignant pleural effusion has been reported, sometimes combined with pleural thickening and nodularity. Pulmonary parenchymal or airway involvement is also umcommon, showing one or more localized masses with lobulated contour and homogenous density, relatively diffuse parenchymal infiltration or endobronchial or endotracheal tumor with atelectasis and obstructive pneumonitis. Other intrathoracic abnormalities include multiple pulmonary nodules and mediastinal lymph node enlargement. In older patients, particularly men, the association of a destructive lesion of one or more ribs with a soft tissue mass protruding into the thorax and indenting the lung is highly suggestive of myeloma 5.肋骨纤维结构不良 Well-circumscribed margin of the tumor with overlying cortical expansion favors benig rather than malignant bone tumor. However, there are multifocal areas of cortical disruption along the tumoral margin. This finding may suggest an aggressive nature of the tumor or malignancy. Fibrous dysplasia is usually a slowly progressive, benign disease that develops over several years and presents with deformity or mild symptoms. It is a benign disorder of bone that can cause cortical thinning as well as bony expansion. On conventional radiography, aggressive fibrous dysplasia may produce opacification and expansion of the underlying bone and apparent disruption of its wall with an associated soft tissue mass. According to Shapeero et al , computed tomography (CT) demonstrated voluminous heterogeneous masses with “ground glass appearance“, calcifications, areas of enhancement, low attenuation, cystic areas, and a thinned, sometimes interrupted, cortical wall. Despite the aggressive clinical course, the CT findings of a “ground glass“ mass with calcifications surrounded by cortical wall, even if incomplete, can suggest the diagnosis of aggressive fibrous dysplasia. There has been also a report of three cases of fibrous dysplasia with aggressive and potentially confusing feature . According to Yao et al , well- defined cortical perforations without associated periosteal reaction were clearly seen on CT. Full-thickness cortical bony destruction can be seen in fibrous dysplasia. This finding, which may only be evident on cross-sectional imaging studies, should not by itself alter a diagnostic impression of fibrous dysplasia supported by other radiographic and clinical features. 5.肋骨纤维结构不良 6.肋骨骨肉瘤 Osteosarcoma(osteogenic sarcoma) constitute 40% of all primary malignant neoplasm of bone. Most patients are between the ages of 10 and 25 years and male to female ratio is 2 : 1. The proliferating tumor cells produce osteoid or immature bone. The most typical sites of involvement are metaphyses of the tubular bones in the appendicular skeleton (80%), particularly the femur (40%), the tibia (16%), and the humerus (15%). Osteosarcomas are relatively infrequent in the fibula, innominate bone, mandible, maxilla in the remainder, they are of soft-tissue attenuation. Variable enhancement of the tumor may be seen following contrast infusion; peripheral enhancement is common. Small areas of calcifications are seen in 5% to 10%. On MR imaging, neurogenic tumors usually have low to intermediate signal intensity on T1- weighted images and inhomogeneously high signal intensity on T2-weighted images. Schwannomas often have peripheral higher signal intensity on T2-weighted images, maybe due to myxoid degeneration. 14、胸骨软骨肉瘤: Chondrosarcomas are the most common malignant tumors of the sternum and are usually seen in patients in the third and fourth decades of life . Usual or conventional chondrosarcoma may be histologically graded as 1 to 3, with grade 1 lesions having the best prognosis . Chondrosarcoma frequently appears as a large, lobulated, excrescent mass with scattered flocculent calcifications characteristic of its cartilaginous matrix, regardless of pathologic types. This tumor usually exhibits intermediate signal intensity similar to that of adjacent muscle on T1WI and high signal intensity on T2WI . Althogh analysis of signal intensity noted on routine MR images does not predict the histologic type or grade of chondrosarcoma, low grade chondrosarcoma usually shows septal and peripheral rimlike enhancement on Gd-enhanced T1WI, corresponding to fibrovascular septation between lobules of hyaline cartilage . 15、侵袭性纤维瘤 侵袭性纤维瘤又称韧带样瘤，是来源于纤维组织的瘤样病变，组织学上主要由成束状交织的 梭形纤维细胞和不等量的致密胶原组织构成，多见于年轻女性，以腹壁发病率最高，胸壁侵 袭性纤维瘤极少见。肿物呈浸润性生长，但很少发生转移。本例侵袭性纤维瘤体积巨大，且 同时累及胸壁、心包、腹腔，属罕见病例，需与纤维肉瘤、间皮瘤鉴别。纤维肉瘤生长迅速 常有包膜，质软，并有坏死液化及囊变，周边可见水肿区；良性胸膜间皮瘤包膜完整，境 界清晰。本病的影像学诊断主要依靠CT和MRI检查。CT能准确地显示出病灶的部位、范围和形 态及与毗邻结构的关系，平扫病灶呈软组织密度，增强扫描病灶强化；MRI检查病灶在TlWI上 呈低信号或等信号，T2WI呈高信号信号强度略低于皮下脂肪，增强扫描病灶明显强化。MRI 和CT对胸壁侵袭性纤维瘤均有较高的诊断价值。 16、胸壁神经内分泌癌 神经内分泌癌是由神经内分泌细胞形成的肿瘤，常见的有嗜铬细胞瘤， 神经节瘤和神经母细胞瘤。胃肠道及其他部位的类癌，胰岛细胞瘤，垂 体腺瘤，甲状腺髓样癌，胃泌素瘤，血管活性肠肽瘤等均属此类。其他 一些少见部位内分泌癌是神经生成激素的功能不一致，统称为神经内分 泌癌(或瘤)或小细胞神经内分泌癌，胸壁神经内分泌癌属此类。本例患 者CT检查能清楚显示该肿瘤的部位、大小、形态、密度以及对周围组织 的侵犯情况，可判定良恶性，但定性诊断有赖于病理组织学及免疫组化 检查。 胸壁肿块及肿瘤的影像诊断 _转自 第2版 Imaging diagnosis of chest wall masses and neoplasms * Chest wall neoplasms are uncommon and include both benign (more likely in an adult) and malignant forms(more likely in a child). These tumors share many imaging features, and both benign and malignant counterparts should be placed in perspective in their evaluation. * If a biopsy is indicated with a suspected malignant chest wall neoplasm, an open surgical biopsy as opposed to a percutaneous image guided needle biopsy is preferred, except when a nonsurgical malignant neoplasm such as Ewings sarcoma is suggested. * Symptoms, usually pain, herald the onset of malignant chest wall neoplasms, whereas benign lesions are usually found incidentally on imaging studies in asymptomatic patients. * Malignant, small, round cell tumors include both Ewings sarcoma and Askin tumors. Magnetic resonance imaging(MRI) is essential in both to assess “skip“ areas of involvement with Ewing sarcoma and sympathetic chain extension with Askin tumors. A large pleural effusion and chest wall mass characterize both of these tumors on imaging. * Malignant fibrous histiocytoma (MFH) tends to arise in areas previously irradiated or within bone infarcts. The imaging features of MFH resemble those of chondrosarcoma. * Chondrosarcomas of the chest wall tend to recur at the local operative site after inadequate resection, directing post-treatment imaging surveillance to the initial tumor site. Chest wall neoplasms are a diverse group of uncommon lesions that include a spectrum of congenital, benign, and malignant soft tissue and bone abnormalities that share many features. An understanding and appreciation of the benign and congenital lesions is implicit in the approach to this topic, which requires discussing the nonmalignant chest wall abnormalities before the aggressive lesions. Although pediatric chest wall tumors are covered in Chapter 36, a brief review of these lesions in this section can help to place the spectrum of these abnormalities in perspective. Chest wall abnormalities discovered in the adult are more likely to be benign than those found in children, biased in part by the frequency of rib fractures in the adult population. This fact should help guide the workup of patients by obtaining rib detail films and defining the nature of the abnormality within the spectrum of the benign lesions reviewed subsequently. Plain films complemented by cross-sectional imaging, primarily with computed tomography (CT), should narrow the list of diagnostic possibilities; however, the examiner should appreciate the behavioral and imaging similarities that may occur within this spectrum of abnormalities. Benign chest wall masses and neoplasms Benign lesions of the chest wall are predominantly of bone origin and are encountered incidentally and most frequently on a chest radiograph being obtained for unrelated reasons. The most common abnormality is a rib fracture, even in patients with a known primary tumor capable of metastasizing to bone. Because the appearance can mimic a more aggressive process, rib fractures should always be considered when evaluating a chest wall abnormality. Benign lesions include