长骨骨干骨肉瘤X线、CT及MRI表现

目的 分析长骨骨干骨肉瘤X线、CT和MRI表现,探讨有关的临床特点和鉴别诊断.方法 28例长骨骨干骨肉瘤患者,均经手术与病理证实,其中病变位于股骨干18例、腓骨干4例、肱骨干4例、胫骨干2例.所有患者均行X线、CT和MR检查,对其影像学表现与手术病理结果进行对照,并由双盲法分析确认.结果 28例中,X线和CT显示广泛骨质破坏16例,骨膜反应22例.X线显示软组织肿块18例,肿瘤骨和瘤样钙化12例.CT平扫显示软组织肿块22例,增强扫描显示软组织肿块24例,肿瘤骨和瘤样钙化16例.MRI显示骨质破坏和骨膜反应10例,软组织肿块26例,其周围可见软组织水肿及骨髓水肿.骨膜反应在SE T1WI上呈等低信号,T2WI呈等信号.软组织肿块在T1WI为等信号,T2WI及STIR呈等高信号.软组织水肿及骨髓水肿在T2WI及STIR呈高信号.MRI增强检查显示病灶均呈不均匀强化,骨髓水肿和软组织肿块均见强化.结论 X线、CT和MRI从不同方面反映长骨骨干骨肉瘤的影像病理特点,其发病率低,骨破坏范围大,无病理性骨折.成骨型骨干骨肉瘤较易诊断,溶骨型应与Ewing瘤、恶性巨细胞瘤等鉴别.

Abstract：

Objective To explore the findings of diaphysial osteosarcoma in long bone on X-ray,CT and MRI, and discuss their clinical features and manifestations for differential diagnosis. Methods Twenty-eight cases with diaphysial osteosarcoma in long bone proved by surgery and pathology were reviewed retrospectively. Eighteen tumors were located in the femur, 4 in fibula, 4 in humerus and 2 in tibia. All of the patients were examined by X-ray, CT and MRI. The imaging manifestations on X-ray, CT and MRI were analyzed, and the relationship of the imaging features with the pathological types was also observed. The imaging signs were correlated with the pathologic findings with a double blind method. Results Of the 28 cases, there were 16 cases with large bone destruction, 22 cases with periosteal reaction on X-ray and CT. On X-ray, 18 cases showed soft tissue mass and 12 cases with neoplastic bone and tumor calcification.While on CT, 22 cases showed soft tissue mass on plain scan and 2 more cases displayed soft tissue mass after the injection of contrast mediun. Sixteen cases showed neoplastic bone and tumor calcification on CT.On MRI, there were 10 cases with bone destruction and periosteal reaction with iso- and hypo-intense on T1WI and iso- signals on T2WI. Twenty-six cases showed soft tissue edema and bone marrow on MRI. The soft mass were iso-signals on T1 WI and iso-hyperintense signals on T2 WI or STIR. The soft tissue edema was found hyperintense signals on T2WI or STIR. The lesions had heterogeneous enhancement especially in bone marrow with edema and adjcent soft tissue. Conclusion The X-ray, CT and MRI can reflect the pathological changes of diaphysial osteosarcoma in long bone from different aspects. Lower incidence, large bone destruction and no pathological fracture were the features of diaphysial osteosarcoma. The osteogenic type is diagnosed easily, but the osteolytic lesion should be differentiated from Ewing sarcoma, malignant giant cell tumor of bone and so on.     

Case report 686

A 13-year-old female presented after repeated trauma with pain of the distal end of the thigh. The findings on plain films, bone scan, and CT were indeterminate. MRI accurately demonstrated a fracture line with bone marrow edema, suggesting the diagnosis of stress fracture. MRI patterns of stress fracture were considered and the importance of establishing the correct diagnosis was emphasized.     

Dynamic contrast-enhanced MR imaging in symptomatic bone stress of the pelvis and the lower extremity

Purpose: To assess the value of dynamic contrast-enhanced MR imaging in bone stress of the pelvis and the lower extremity.Material and Methods: Thirty patients (37 reactions; aged 17-25 years, mean 20.5 years) with MR findings of 37 bone stress reactions were examined using dynamic gadolinium contrast enhancement. The enhancement was evaluated with time-intensity curves. The highest slope and maximum enhancement values were calculated and compared with the different precontrast MR imaging signs of bone stress reactions.Results: There was a significant difference in the highest slope values between the site of the bone stress reaction and the reference points. In 24 of the 37 reactions the dynamic contrast enhancement was regarded as positive. A fracture line, callus, and muscle edema were the MR imaging signs which had a significant correlation to the dynamic contrast enhancement. Neither periosteal nor marrow changes showed any significant correlation. A new MR grading system for bone stress reactions could be assessed.Conclusion: Increased tissue perfusion could be seen if precontrast MR imaging revealed callus, fracture line or muscle edema surrounding the bone stress reaction.     

足踝部X线表现阴性痛风性关节炎的CT与MRI表现对比研究

目的:对足踝部X线平片表现阴性痛风患者的CT和MRI表现进行对比研究,评估其隐匿性骨质破坏及其他影像学表现。方法:收集于我院就诊的36例X线平片阴性痛风患者,于2周内均行CT与MRI平扫,分析骨质破坏、关节内和/(或)周围痛风石、软组织肿胀、关节腔积液、滑膜增厚和骨髓水肿等征象。结果:36例CT平扫可见骨质破坏23例,MRI可见13例,二者差异有统计学意义(P=0.002)。CT平扫可见关节内和/(或)周围痛风石23例,MRI可见27例,二者差异无统计学意义(P=0.289);其中21例CT、MRI均见痛风石表现,6例仅MRI可见,2例仅CT可见。CT与MRI平扫分别有11例和15例可见关节腔积液表现,二者差异无统计学意义(P=0.125)。2种检查均见软组织肿胀24例,差异无统计学意义(P=1.000)。另外,36例的MRI平扫中,4例可见滑膜增厚,30例见骨髓水肿表现。结论:CT与MRI平扫可显示X线平片无法显示的隐匿性骨质破坏及微小痛风石,CT平扫对于早期骨质破坏的显示优于MRI,但MRI可提供更多影像信息。对于足踝部X线表现阴性痛风性关节炎,CT与MRI相结合为最佳检查手段。     

The septic versus nonseptic inflamed joint: MRI characteristics

Objective. To differentiate the MR features of septic versus nonseptic inflamed joints. Design and patients. Thirty patients were referred for MRI with inflamed joints (19 were subsequently found to be septic and 11 nonseptic). At 1.5 T enhanced MRI five groups of signs related to joint space, synovium, cartilage, bone and peri-articular soft tissue respectively were assessed and compared between the septic and nonseptic groups. Results. The prevalence of MRI findings in septic versus nonseptic joints (respectively) was as follows: effusion (79% vs 82%), fluid outpouching (79% vs 73%), fluid heterogeneity (21% vs 27%), synovial thickening (68% vs 55%), synovial periedema (63% vs 55%), synovial enhancement (94% vs 88%), cartilage loss (53% vs 30%), bone erosions (79% vs 38%), bone erosions enhancement (77% vs 43%), bone marrow edema (74% vs 38%), bone marrow enhancement (67% vs 50%), soft tissue edema (63% vs 78%), soft tissue enhancement (67% vs 71%), periosteal edema (11% vs. 10%). The presence of bone erosions appeared to be an indicator for an infected joint (P=0.072); coexistence of bone marrow edema slightly improves the significance (0.068). A similar trend was obtained when combining bone erosions with either synovial thickening, synovial periedema, bone marrow enhancement or soft tissue edema (P=0.075). Conclusions. The combination of bone erosions with marrow edema is highly suggestive for a septic articulation; the additional coexistence of synovial thickening, synovial edema, soft tissue edema or bone marrow enhancement increases the above level of confidence. Similar to conventional radiography, the single sign that appeared to show a significant trend was the presence of bone erosions. However, no single sign or combination could either be considered pathognomonic or exclude the presence of a joint infection. Received: 18 February 1999 Revision requested: 6 April 1999 Revision received: 26 July 1999 Accepted: 26 July 1999     

股骨头缺血性坏死的CT/MRI特征性表现比较分析

目的:探讨CT/MRI特征表现在股骨头缺血坏死中的诊断价值.方法:分析和总结60例86髋经临床确诊为股骨头缺血性坏死的影像学资料.全部病例均同期行MRI、CT检查.结果:①18个早期病变中,CT示10个表现骨小梁结构模糊,16个表现单纯高密度硬化；MRI示15个出现骨髓水肿,13个有“线样征”；②68个中晚期病变中,股骨头骨小梁断裂及皮质塌陷,CT 45个,MRI 30个(P＜0.01)；髋臼病变并骨质疏松,CT 49个,MRI 35个(P＜0.01).MRI显示51个关节积液.其他影像学表现两者类似.结论:骨髓水肿,“线样征”是早期股骨头缺血性坏死MRI特征性表现.骨小梁结构模糊、中断、碎裂骨折、皮质塌陷及骨质疏松改变CT优于MRI.     

软骨母细胞瘤MRI及X线平片和CT的表现特征

目的 研究软骨母细胞瘤的影像表现,探讨其MRI与X线平片、CT征象的对应关系.方法 分析16例经手术、病理证实的良性软骨母细胞瘤的影像资料,总结其MRI表现与X线平片、CT征象的对应关系.结果 16例软骨母细胞瘤均位于骨骺,大小为0.9 cm×0.8 cm×1.0 cm～4.8 cm×4.3 cm×5.1 cm,呈不同程度的分叶状.在T1WI上以等、低信号为主,T2WI上呈混杂信号,CT上为软组织密度,内见钙化和更低密度区.边缘呈长T1、短T2信号,在CT上表现为硬化边.MRI可见病灶周围有骨髓水肿,在X线和CT上表现为骨质硬化区.病灶邻近软组织肿胀.MRI显示骨膜异常9例,8例与病灶不相邻;X线和(或)CT显示骨膜新生骨6例.MRI显示关节积液12例,CT显示6例.MRI上病灶均呈不均匀强化,骨髓水肿、骨膜反应和软组织肿胀均见强化.软骨母细胞瘤在扩散加权成像(DWI)上呈等、高信号,在MR平扫中的等T1、等T2成分和长T1、长T2成分,以及骨髓水肿、骨膜反应和软组织肿胀在DWI上均呈高信号.结论 MRI和X线平片、CT从不同方面反映软骨母细胞瘤的病理改变,联合应用不同检查手段可更全面显示软骨母细胞瘤的特点.     

Distinguishing stress fractures from pathologic fractures: a multimodality approach

Whereas stress fractures occur in normal or metabolically weakened bones, pathologic fractures occur at the site of a bone tumor. Unfortunately, stress fractures may share imaging features with pathologic fractures on plain radiography, and therefore other modalities are commonly utilized to distinguish these entities. Additional cross-sectional imaging with CT or MRI as well as scintigraphy and PET scanning is often performed for further evaluation. For the detailed assessment of a fracture site, CT offers a high-resolution view of the bone cortex and periosteum which aids the diagnosis of a pathologic fracture. The character of underlying bone marrow patterns of destruction can also be ascertained along with evidence of a soft tissue mass. MRI, however, is a more sensitive technique for the detection of underlying bone marrow lesions at a fracture site. In addition, the surrounding soft tissues, including possible involvement of adjacent muscle, can be well evaluated with MRI. While bone scintigraphy and FDG-PET are not specific, they offer a whole-body screen for metastases in the case of a suspected malignant pathologic fracture. In this review, we present select examples of fractures that underscore imaging features that help distinguish stress fractures from pathologic fractures, since accurate differentiation of these entities is paramount.     

Assessing radiographically occult upper extremity fractures with dedicated extremity MRI

Purpose: To examine the utility of low-field, dedicated extremity MRI for assessing acute upper extremity trauma in patients with radiographs that are negative for fracture. Secondly, to determine which sequences are most useful when screening for fractures. Methods: Forty-four of 46 patients with acute upper extremity trauma and initial radiographs negative for fracture were imaged with a 0.2-T MRI system. Findings were verified with follow-up clinical assessment and plain radiography. Results: In 21 patients, dedicated extremity MRI demonstrated 26 ultimately proven occult fractures, none of which were seen on the initial conventional radiographs. True fractures demonstrated marrow edema and a linear fracture line on low-field MRI. One bone contusion showed edema with no fracture line and was misdiagnosed as a fracture. Low-field MRI correctly identified 23 remaining patients with no fracture. Sensitivity and specificity for fracture in the 44 patients successfully imaged were 100 % and 96 %, respectively. Additionally, 21 soft-tissue injuries were found incidentally by MRI. However, these may not merely be incidental findings of an acute nature, but may very well be chronic, and therefore merit no specific treatment. T1-weighted gradient-echo and short-tau inversion recovery sequences demonstrated the fracture line and marrow edema to best advantage, and were thus the most useful sequences to assess fractures on low-field MRI. Conclusion: Extremity MRI is highly sensitive and specific for radiographically occult fractures of the upper extremity and can also identify associated soft-tissue injuries. In our study, the management was altered in 45 % of the patients following MRI. When adequate sequences are used this modality can direct appropriate therapy while obviating the added expense and morbidity of unnecessary immobilization and follow-up imaging of patients without fracture.     

双能量CT虚拟去钙化成像诊断下肢关节外伤性骨髓水肿

目的:探讨双能量CT虚拟去钙化(VNCa)成像在急性创伤性下肢关节骨髓水肿的诊断价值.方法:连续纳入2018年1月至2019年5月张家港澳洋医院30例急性下肢关节创伤患者.由两名放射科医师对所有病例VNCa图像进行评估,确定是否存在骨髓水肿.以磁共振图像作为参考标准,评估VNCa图像诊断下肢关节骨髓水肿敏感性、特异性、...     

Subchondral insufficiency fracture of the femoral head: magnetic resonance imaging findings correlated with micro-computed tomography and histopathology

We described magnetic resonance (MR) imaging findings of subchondral insufficiency fracture of the femoral head without collapse in which micro-computed tomography (CT) and histopathologic studies were performed. Magnetic resonance imaging showed a subchondral low-signal intensity band, which corresponded to the fracture callus. Diffuse bone marrow edema with contrast enhancement effect was seen in both the proximal and distal segments of the low-signal intensity band. These features are distinct from those of avascular necrosis.     

Osteoid osteoma: MR imaging revisited

To assess and compare with computed tomography (CT) the performance of magnetic resonance (MR) imaging in the detection of osteoid osteoma, and determine the features of this lesion on MR imaging. The prospective MR imaging and CT diagnosis of osteoid osteoma was determined from original radiology reports. MR images were assessed retrospectively with regard to the location and signal intensity of the nidus and surrounding bone marrow and soft tissue edema. These findings were correlated with the age of the patient, duration of symptoms, and drug therapy. Ten patients with histologically proven osteoid osteoma who underwent MR imaging were reviewed. All 10 lesions were correctly diagnosed at the time of MR imaging. None of the lesions was intracortical. Nine lesions were intra-articular. Two out of five patients with extracortical lesions had false negative CT preceding the MR study. Signal intensity of the nidus, marrow, and soft tissue edema on MR imaging were variable. Perinidal edema was most pronounced in younger patients and had no apparent relation to drug therapy. MR imaging reliably demonstrates the nidus of an osteoid osteoma, which has a variable appearance related to its position relative to the cortex of the bone. A predominance of cancellous osteoid osteomas are encountered in patients referred for MR imaging. Marrow edema in the vicinity of the lesion improves the conspicuity of the nidus. CT may fail to diagnose osteoid osteoma when the nidus is in a cancellous location, due to the lack of perinidal density alteration.     

骨良性肿瘤与肿瘤样病变的MR诊断

目的：探讨磁共振在骨良性肿瘤与肿瘤样病变诊断中的价值。材料和方法：搜集骨良性肿瘤与肿瘤样病变３４例，分析其磁共振表现。全部病例均做磁共振检查。采用常规ＳＥ序列，Ｔ１Ｗ及Ｔ２Ｗ成像。其中２０例同时做了脂肪抑制成像。结果：磁共振诊断正确率为９４．１％（３２／３４）。磁共振征象包括：骨质破坏（３０／３４）；软组织肿块（３／３４）；关节侵犯（１／３４）；骨壳（１０／３４）；硬化缘（１７／３４）；钙化（３／３４）；骨间隔（７／３４）；囊变坏死（８／３４）；出血（７／３４）；软组织水肿（３／３４）；髓腔水肿（３／３４）；关节积液（３／３４）。结论：磁共振是骨良性肿瘤与肿瘤样病变的有效辅助诊断方法。磁共振与平片、ＣＴ相结合有利于提高定性诊断正确率。     

骨样骨瘤的影像学诊断

目的 分析骨样骨瘤的X线、CT和MRI表现。方法 搜集经手术病理证实的骨样骨瘤48例，其中男33例，女15例。所有病例均行X线检查，其中同时行CT检查者32例，行MR检查者10例，3种检查方法都进行者8例。分析骨样骨瘤在X线、CT和MRI上的表现及其对瘤巢和瘤巢周围改变的显示能力。结果 48例病灶均表现为一圆形或卵圆形的透亮区，直径为0．4～1．7cm，平均9．7cm，其周围有不同程度的骨质硬化。10例行MR检查者均可见瘤巢周围的软组织、骨髓水肿或关节腔积液。48例X线平片仅37例显示瘤巢，32例行CT检查者均清楚显示瘤巢，X线和CT对瘤巢显示率分别为77％(37／48)和100％(32／32)。10例MR检查者均可作出正确诊断，其中8例能直接判断出瘤巢，另2例需对照平片或CT才能肯定。结论 瘤巢是确诊骨样骨瘤的关键，X线平片仍然是诊断骨样骨瘤的重要检查方法，CT是显示瘤巢的最佳方法，MRI能敏感地显示瘤巢周围骨髓内及软组织的炎性水肿，但可能造成误诊，结合平片或CT可作出准确诊断。     

成软骨细胞瘤影像学诊断

目的 探讨成软骨细胞瘤影像学表现特点。资料与方法 分析22例经手术病理或穿刺活检证实的成软骨细胞瘤资料,总结其X线平片、CT和MRI表现。结果 胫骨上端18例,股骨下端2例,肱骨上端2例。表现为骨骺区分叶状骨质破坏区,内见钙化和更低密度区;MR T1WI以低信号为主,T2WI上信号混杂,扩散加权成像（DWI）上呈等高信号。硬化边厚薄不一。病灶周围在X线和CT上见高密度骨质硬化区,MRI表现为骨髓水肿。骨膜反应常不与病灶相邻,MRI上为长T1、短T2信号,与皮质间见条状高信号。邻近软组织肿胀,部分患者见关节积液。MRI上病灶可呈环状或较均匀强化,骨髓水肿、骨膜反应和软组织肿胀均强化。结论 成软骨细胞瘤影像学表现较有特征性,结合X线平片、CT和MRI能做出正确诊断。     

Hyperplastic callus formation in osteogenesis imperfecta: CT and MRI findings

Hyperplastic callus formation is a noteworthy condition in patients with osteogenesis imperfecta because it often mimicks osteosarcoma on radiography. The findings of CT and MRI in hyperplastic callus formation have not been reported. In the presented case, MRI demonstrated contrast enhancement and edema of the surrounding soft tisssue, consistent with benign as well as malignant disease. Computed tomography showed a calcified rim of the lesion which may be a useful feature to rule out osteosarcoma in this condition. Received 7 August 1997; Revision received 17 November 1997; Accepted 24 December 1997     

暂时性骨质疏松症的MRI表现

目的:探讨暂时性骨质疏松症的MRI表现。方法:对经临床证实的10例暂时性骨质疏松症(TOH)患者的临床及影像学资料进行回顾性分析。10例患者均行MRI平扫,其中5例行MRI增强扫描,4例行CT扫描。10例中男7例,女3例,年龄为25～40岁。结果:10例TOH中,双侧髋关节同时受累2例,单侧受累8例,主要MRI表现为弥漫性骨髓水肿,累及股骨头、颈及转子间,股骨头形态完整,1例可见软骨下应力性骨折,所有病例均无股骨头软骨下骨质缺损;关节囊肿胀和关节积液8髋;MRI增强扫描示病变区呈明显均匀强化。主要CT表现为股骨头骨密度弥漫性减低,骨皮质变薄。治疗5～11个月后患者疼痛症状消失,股骨内MRI信号恢复正常。结论:CT上表现为弥漫性骨质疏松、MRI表现为弥漫性骨髓水肿、缺乏软骨下骨质病变以及均匀一致强化是TOH性特征的影像学表现。     

骨样骨瘤的X线、CT和MRI表现和诊断价值

目的分析骨样骨瘤的X线、CT和MRI表现,评价它们的诊断价值。方法经手术病理证实,同时有X线、CT和MRI检查的骨样骨瘤22例,其中男19例,女3例。分析X线、CT和MRI对瘤巢和瘤巢周围改变的显示能力。结果X线、CT和MRI分别有17、22和20例表现为有一圆形或卵圆形小于2cm的瘤巢,瘤巢周围可有程度不一的骨质硬化、骨膜反应、软组织及骨髓腔水肿或相邻关节的肿胀。X线诊断的准确率为77.3%（17/22）;CT诊断的准确率为100%（22/22）;MR诊断的准确率为90.9%（20/22）。结论大多数的骨样骨瘤具有较典型的影像学表现,易于诊断,其中以CT对瘤巢的定位最为准确,单凭X线或MR的表现可因未能显示瘤巢而误、漏诊。     

成软骨细胞瘤的MRI表现特点

目的 分析成软骨细胞瘤的MRI表现特点.方法 对经病理证实的20例成软骨细胞瘤的MRI信号特点、病灶形态和生长方式,以及周围骨髓和软组织有无水肿、有无骨膜反应、相邻关节有无积液等征象进行分析.结果 20例病灶在T1WI和T2WI上表现为不均质的混杂信号,病灶形态为分叶状;16例病灶呈膨胀性生长;18例病灶周围出现骨髓水肿;14例病灶周围软组织水肿;6例病灶周围有骨膜反廊;7例病灶突破骨皮质向周围突出;6例棚邻的关节有关节积液.结论 成软骨细胞瘤在MRI上多表现为分叶状和膨胀性生长,病变呈不均质混杂信号,病灶周围有明显的骨髓水肿和邻近软组织水肿.     

儿童神经母细胞瘤颅面骨转移的影像表现

目的 探讨儿童神经母细胞瘤颅面骨转移的影像表现.方法 回顾性分析12例经组织学证实的儿童神经母细胞瘤的影像表现.其中 10例患儿行CT平扫,6例行MRI,7例行全身SPECT骨扫描.结果 行CT检查的10例患儿中,9例表现为颅面骨溶骨性骨质破坏伴软组织肿块,其中8例可见骨膜反应,3例表现为特征性的针状骨膜反应;另l例cT未发现异常但骨扫描显示异常.行MR检查的6例患儿均表现为颅面骨骨髓腔信号异常伴周围软组织肿块,其中5例行增强扫描,骨髓腔异常信号影和软组织肿块呈明显不均匀强化.7例行全身骨扫描,均可见颅面部放射性浓聚区,其巾6例伴有全身其他部位的骨转移.结论神经母细胞瘤颅面骨转移有一定的影像特征,可提示诊断.