204.CASE：5-year-old boy with thigh pain, swelling
每天朗读一段医学影像学英语文章
History: A 5-year-old boy presents to the emergency department with worsening right thigh pain and swelling.
病史：患者男，5岁，因右侧大腿疼痛肿胀收入急诊室。股骨正侧位片如下。
Frontal and lateral radiographs of the femur were obtained.
股骨正侧位片如下。
Findings
Radiographs: There is a permeative lesion with cortical disruption, wide zone of transition, soft-tissue component, and periosteal reaction involving the right distal femur. This lesions is centered in the distal femur and extends from the metadiaphysis to the level of the distal physis. There is radiographic sparing of the epiphysis. This lesion is highly suspicious for a primary osteosarcoma. The joint spaces are maintained. No skip lesions or soft-tissue lesions are identified.
影像表现：
平片：右侧股骨远端可见一弥漫性病变，伴骨皮质破坏，移行区增宽，有软组织成分，可见骨膜反应。该病变位于股骨远端中央，从干骺端蔓延至远端生长端。骨骺在平片上显示未受累。高度怀疑原发性骨肉瘤，关节间隙正常，未见其他转移或软组织病变。
MRI: There is a large, destructive, heterogeneously enhancing marrow-replacing expansile lesion with a large osseous soft-tissue component centered within the distal right femoral metadiaphysis. This lesion extends proximally into the midfemoral marrow cavity and the distal femoral physis posteriorly but does not appear to involve it, and it does not involve the right knee joint. This aggressive-appearing lesion expands and displaces the periosteum around the distal femur and is associated with perilesional edema, as well as causes mild posterior mass effect on the adjacent popliteal vasculature. This mass effect results in narrowing of the popliteal vein; however, the vein remains patent. There is no evidence of encasement of the neurovascular bundle within the posterior right leg. There are no additional skip lesions within the right femur and no lymphadenopathy within the pelvis or imaged right lower extremity. These findings, in conjunction with recent radiographs, are highly suspicious for a primary osteosarcoma.
MRI：右侧股骨干骺端中央可见一巨大、有破坏性的、不均匀强化的膨大病变，代替了骨髓组织，伴骨性软组织成分。该病变范围从近端股骨中段的骨髓腔，蔓延至远端股骨骨骺，但并未累及骨骺，也未累及右侧膝关节。该病变有侵袭性行为，使股骨远端骨膜不断膨胀并更换，形成病变周围水肿。还导致附近腘窝血管结构轻度后方占位效应。占位效应使腘静脉受压狭窄，但仍未闭合。未见右腿后方神经血管束包绕。右侧股骨无其他转移性病变。图中盆腔和右下肢淋巴结为见肿大。以上表现，结合平片表现，高度提示原发性骨肉瘤。
Diagnosis: High-grade osteosarcoma of the right distal femur, primary origin
诊断：右侧股骨远端高级别骨肉瘤（原发性）
Notes：
1. femur [ˈfimɚ] n. 股骨
2. permeative ['pɜːrmieɪt] 渗透，弥漫
3. periosteal [pɪəri:oʊs'tel] 骨膜的
4. epiphysis [ɪ'pɪfɪsɪs] n. 骨骺
5. osteosarcoma [ˌɒsti:oʊsɑ:'koʊmə] n. 骨肉瘤
6. periosteum [ˌperɪ'ɒstɪrm] n. 骨膜
7. popliteal [pɒp'lɪtɪrl] adj.
来源：每天朗读一段医学影像学英语文章
圈主
深圳市人民医院放射科副主任医师杨敏洁