毛细血管扩张型骨肉瘤的影像表现及其与病理的关系

目的:分析毛细血管扩张型骨肉瘤影像学表现与病理的关系,以提高诊断准确性.方法:回顾性分析经手术病理证实的毛细血管扩张型骨肉瘤9例,术前分别经X线平片、CT平扫、MR SE T1WI、T2WI和T1WI增强扫描,仔细复习影像征象并和手术病理作对照.结果:9例毛细血管扩张型骨肉瘤中,位于股骨5例,胫骨3例和髂骨1例.位于长管状骨者,5例位于干骺端,2例位于骨干,1例接近骨端.肿瘤直径6.3～11.8 cm.所有肿瘤均为溶骨性骨质破坏,破坏区呈椭圆形5例,不规则地图形4例.病灶呈囊状9例,7例病灶境界不清,7例病变见骨膜增生,伴软组织肿块8例,所有病例软组织肿块境界清楚.5例行CT检查,病灶密度低于肌肉或与肌肉相仿,CT显示骨膜增生及软组织肿块较平片清楚,增强扫描软组织明显强化.4例行MR检查,T1WI为混杂信号3例,低信号1例;T2WI为低、等和高信号混杂4例.T2WI 4例均可见明显囊状改变和液-液平面,均可见软组织成分,软组织构成囊壁和分隔,部分呈不规则肿块结节,T2WI软组织信号高于肌肉.结论:毛细血管扩张型骨肉瘤好发于长管状骨干骺端,呈卵圆形或地图样溶骨性破坏,容易呈多囊状坏死,但肿瘤内常见软组织成分,常伴骨膜增生和骨外软组织肿块,CT增强扫描和MR有助于显示病灶的软组织成分.     

髓内高分化骨肉瘤的影像学诊断

目的:探讨髓内高分化骨肉瘤的影像表现及其诊断价值.方法:分析经穿刺或手术病理证实的22例髓内高分化骨肉瘤的X线、CT及MR影像资料特点.其中,19例行X线平片检查,14例行CT检查,19例行MR检查(增强16例).结果:男13例,女9例,平均年龄40.1岁.11例位于股骨骨端,8例位于胫骨骨端,1例位于肱骨近端,1例位于桡骨中段,1例位于腓骨上段;其中,1例转移至肩胛骨关节盂,1例转移至肱骨近端、肩峰及胸椎.X线示混合型骨破坏19例,伴有局部骨皮质突破17例;9例见软组织肿块;5例伴骨膜反应.14例CT扫描中,边界不清的混合型骨破坏13例,1例病灶周缘有明显硬化边.19例MR扫描中,病灶呈T1WI等低、T2WI STIR等高信号,强化明显,其中9例见到骨外软组织肿块形成,其余均见到程度不等的软组织肿胀表现.结论:髓内高分化骨肉瘤以长骨骨端边界不清的混合型骨破坏、瘤骨形成量多少不一为典型表现,有助于诊断与鉴别诊断.     

结节性筋膜炎的影像表现

目的 分析结节性筋膜炎(NF)的CT及MRI表现,以提高影像诊断水平.方法 回顾性分析经手术病理证实的9例NF的影像表现,其中4例行CT检查,5例行MR检查.结果 9例NF中,5例位于下肢,2例位于腹壁,2例位于外耳道.病灶最大直径为1.1～9.5 cm,平均(3.7±0.3)cm.所有病灶均表现为单发实性软组织肿块,CT平扫显示肿块密度与肌肉密度相仿;病灶在MR T_1WI呈等低信号,在T_2WI呈混杂高信号,增强扫描肿块呈均匀或不均匀中、重度强化.结论 CT及MR检查能为临床诊断及鉴别诊断NF提供有价值的信息.     

原发性骨骼恶性纤维组织细胞瘤影像表现与病理对照研究

目的 分析原发性骨骼恶性纤维组织细胞瘤(MFH)影像表现与病理的关系,以提高诊断准确性.方法 回顾性分析经手术病理证实的原发性骨骼MFH 13例,术前分别经X线平片、CT平扫、MR SE T1 WI、T2 WI和增强T1 WI检查,复习影像表现并与手术病理作对照.结果 13例原发骨骼MFH中,11例位于骨端,2例位于骨干,位于骨端者与骨性关节面的距离为1～5 cm.肿瘤呈溶骨性骨质破坏,直径5.3～12.7 cm.其中,破坏区偏心10例,破坏区内见少许分隔7例,周边不连续硬化11例,伪足样突起7例,骨膜增生2例,软组织肿块9例,所有患者软组织肿块体积较小.CT扫描显示肿瘤密度与肌肉密度相仿.在MR T1 WI肿瘤为等低信号,在T2 WI为混杂信号,T2 WI常见片状等低信号,病灶周围常见不完整的低信号环,环外见伪足样突起.动态增强呈进行性延迟强化,强化显著,且较均匀.大体病理显示病灶偏心,膨胀不明显,肿瘤多突破皮质形成范围较小的软组织肿块,呈结节状或假性包裹样,肿瘤内见纺锤形成纤维细胞和胞体较小的组织细胞样细胞,伴有数量不等的胶原纤维,细胞密集呈席纹状或放射状排列.肿瘤微血管丰富.结论 原发骨骼MFH好发于中年患者长骨骨端,T2 WI常见等低信号成分,增强扫描强化显著;MRI表现与病理关系密切.     

骨良性纤维组织细胞瘤的影像诊断分析

目的探讨骨良性纤维组织细胞瘤(BFH)的影像学表现及诊断价值。方法回顾性分析经病理证实的16例(男9例,女7例)BFH患者,其中股骨7例,胫骨4例,肱骨1例,桡骨1例,髂骨2例,腰椎1例。X线平片检查16例,CT平扫8例,MRI平扫及增强检查13例。结果影像学表现为膨胀性骨质破坏,病灶边界清楚,所有病灶均未见骨膜反应及周围软组织肿块形成。X线示灶周硬化12例,病灶内呈磨玻璃样改变9例。CT示病变密度不均匀,呈与肌肉密度相仿的软组织密度影,灶内见骨性分隔及骨嵴5例,骨皮质中断2例。MRI示病灶T1WI呈等低信号,T2WI呈不均匀高信号或等低信号,增强后不均匀强化。MRI表现各异由病理组织成分不同所决定。结论 BFH的影像学表现具有一定特征,有助于该病的正确诊断及鉴别诊断。     

原发性骨淋巴瘤的影像学表现

目的探讨原发性骨淋巴瘤（PLB）的MRI、CT表现特点。资料与方法回顾性分析经病理学证实的6例PLB患者的MRI、CT表现资料。结果MR检查病灶信号强度在T1WI上与肌肉类似;2例行T2WI,信号强度高于肌肉低于脂肪;在脂肪抑制T2WI上呈高信号,其中信号较均匀4例;2例行扩散加权成像（DWI）,呈明显高信号。MRI上4例可见软组织肿块,其中2例未见骨皮质破坏,CT检查1例,未见骨质破坏;另2例骨皮质明显破坏,均行CT检查,1例骨皮质部分性中断,1例骨皮质明显破坏。骨皮质内条状高信号1例。结论PLB信号较均匀,软组织肿块明显而骨皮质破坏较轻,较具有特征性。     

原发性侵袭性骨母细胞瘤的影像学表现(附3例并文献回顾)

目的 探讨骨原发性侵袭性骨母细胞瘤的影像学表现.方法 对3例经病理证实的原发性侵袭性骨母细胞瘤的临床资料回顾性分析,结合文献报道,对其影像表现进行探讨.3例均摄取X线平片,其中2例同时行CT平扫,1例同时行CT平扫及MR平扫.结果 胫骨2例,肱骨1例.平片及CT均表现为骨端膨胀性骨质破坏,病灶内有钙化或骨化,周围薄壳样硬化带,骨皮质变薄,2例出现局部皮质中断、消失.1例MR平扫表现为与肌肉呈较均匀等T1长T2膨胀性骨质破坏,局部与周围肌肉分界不清,病变周围出现软组织肿块,无骨膜反应.结论 X线平片可作为侵袭性骨母细胞瘤基础性检查手段,结合CT及MR可提高诊断的符合率.     

骨良性纤维组织细胞瘤的影像学分析

目的 :探讨骨良性纤维组织细胞瘤(BHF)的影像学特点,以提高该病影像学诊断水平。方法 :回顾性分析19例经手术病理证实为BFH的影像学表现并进行分析。结果:19例均为单发,病灶发生在长管状骨14例,不规则骨4例(椎骨2例,骶骨1例,下颌骨1例),扁骨(肋骨)1例。X线及CT表现为膨胀性、溶骨性骨质破坏,呈偏心性或中心性生长,病灶内见残留骨棘,周边见硬化边,骨皮质可部分断裂,未见明显骨膜反应,未见软组织肿块。MRI检查示病灶T1WI呈较均匀等信号,T2WI呈较均匀稍高信号影,也可呈等高混杂信号,病灶内及病灶周边可见条索状低信号;增强扫描呈较明显、持续强化。3例合并动脉瘤样骨囊肿。结论:BFH影像学表现具有一定特征,结合临床、病理表现,可提高其诊断准确率。     

原发性骨淋巴瘤综合影像学分析

目的：探讨原发性骨淋巴瘤的影像表现的诊断价值.材料和方法：回顾性分析经病理证实的15例原发性骨淋巴瘤的X线、CT及MR影像资料.结果：15例中骨盆受累7例、脊柱受累6例、肩胛骨及股骨受累各2例,肋骨受累1例.X线平片或CT检查的病例中,骨质破坏主要为溶骨型和浸润型12例,囊状膨胀型及混合型各1例,12例骨质破坏的周边可见不同程度的软组织肿块.MR T1WI信号类似或稍高于肌肉9例（9/11）,T2WI信号高于肌肉低于脂肪10例（10/11）,MR信号不均匀6例.结论：轻微的骨质破坏伴明显软组织肿块表现可提示原发性骨淋巴瘤的诊断,但需结合临床和病理确诊.     

骨良性纤维组织细胞瘤临床影像分析(附8例报告)

目的:探讨骨良性纤维组织细胞瘤的影像及临床特点,提高对该病影像表现的认识.方法:回顾性分析8例经手术证实骨良性纤维组织细胞瘤患者的临床资料及影像表现,并结合近年来国内外相关文献进行分析与综合.结果:病变7例为单发病灶,其中6例发生在长管状骨,X线及CT检查表现为溶骨性骨质破坏,偏心或中心生长,可见骨皮质中断及部分硬化边,周围未见软组织肿块.2例行MR检查,病灶表现为T1WI呈等低信号,T2WI呈等高信号,病灶周围见低信号带,病灶增强后明显强化.结论:骨良性纤维组织细胞瘤临床及影像表现有一定特点,综合发病部位及影像表现,有助于该病的诊断及鉴别诊断.     

Stress MR imaging for evaluation of popliteal artery entrapment

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young healthy volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.     

MR imaging of muscle and tender points in fibromyalgia

Fibromyalgia is a syndrome manifested by chronic, diffuse muscu-loskeletal aching and soreness, palpable muscle tender points, and other symptoms. Standardized clinical diagnostic criteria have recently been developed. Skeletal muscle has been postulated as the end organ in this disease. Biochemical, histologic, electromyographic, and conventional radiographic studies have demonstrated no definitive abnormality. This study sought to establish whether magnetic resonance (MR) imaging could demonstrate any abnormality in these patients. Eighteen patients were entered in the study, 14 of whom were able to complete their examinations. T1 -weighted, T2-weighted, gradient-echo, and STIR (short-tau inversion-recovery) sequences were performed in all patients, with selected patients examined with T1weighted, gadopentetate dimeglu-mine-enhanced sequences. The trapezius and suboccipital regions were imaged in patients who, clinically, had active fibro-myalgia. No abnormalities could be detected. The authors conclude that the conventional MR imaging used in this study was unable to depict any primary skeletal muscle abnormality in fibromyalgia.     

MR angiography of congenital heart disease: Value of segmented two-dimensional inflow technique and maximum-intensity-projection display

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40–50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65° and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.     

MR imaging of disorders of the brachial plexus

The authors evaluated 64 consecutive patients with suspected brachial plexus (BP) abnormalities of diverse cause with magnetic resonance (MR) imaging, using the body coil and a standardized protocol. Of the 43 patients for whom follow-up was available, 25 were suspected of having neoplastic involvement of the BP, nine had sustained injuries, and nine presented with BP symptoms of uncertain cause. MR imaging was 63% sensitive, 100% specific, and 77% accurate in demonstrating the abnormality in this diverse patient population. When patients with neoplastic and traumatic disorders were considered separately, sensitivity increased to 81%, accuracy to 88%, and specificity remained unchanged. In the patients with a clinical diagnosis of idiopathic or viral plexitis, the MR imaging findings were normal, serving to exclude other structural abnormalities. It is concluded that MR imaging is valuable in the assessment of a wide range of BP disorders.     

MR imaging characteristics of noncancerous lesions of the prostate.

Radical prostatectomy specimens from 53 men with clinical stage A or B prostate cancer were retrospectively reviewed and compared with correlative axial T2-weighted magnetic resonance (MR) images obtained just before surgery. Non-cancerous lesions were evaluated for signal intensity and location. Focal high-signal-intensity areas (n = 72) were present in 81% of patients. The 26% of lesions seen in the central gland all correlated with cystic atrophy. Of the 53 lesions seen in the peripheral prostate, 47 (89%) were cystic atrophy without associated cancer, four (7.5%) cystic atrophy with cancer, and two (3.8%) focal inflammation. Focal low-signal-intensity areas (n = 42) were present in 60% of patients. Of the 31% of lesions in the central prostate, one-fifth correlated with benign prostatic hyperplasia (BPH) and four-fifths with fibrous tissue. Of the 69% of peripheral lesions, 83% corresponded to fibrous tissue, 10% to BPH, and 7% to normal tissue. Mixed lesions (n = 42) were present in 64% of patients; 86% of these were located centrally and 14% peripherally. All mixed central lesions were BPH; the peripheral lesions were areas of combined cystic atrophy and fibrosis. BPH of low or mixed signal intensity can extend into the peripheral prostate and mimic cancer. High-intensity cystic atrophy associated with cancer can mimic normal tissue.     

肾细胞癌的MRI研究进展

肾细胞癌是最常见的成人肾脏恶性肿瘤。近年来，多种功能MRI成像技术（如扩散加权成像、灌注加权成像等）、多参数MRI联合分析以及影像组学等新兴影像处理技术被证实在肾细胞癌的诊断中具有较大的价值。目前，研究热点多集中于良恶性肿瘤的鉴别、组织学亚型的区分、肿瘤分期、预测核分级及判断预后。就MRI新技术及图像处理技术在肾细胞癌中的研究进展予以综述。     

Dynamic contrast-enhanced MR imaging assessment of vascularized free fibular grafts

Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.     

Influence of in vivo copper on MR images of the liver in rats

To investigate the effects of in vivo copper on magnetic resonance (MR) images, the authors studied Long-Evans cinnamon rats, which develop hepatitis and hepatocellular carcinoma as a result of abnormal copper metabolism. The livers of the rats were imaged before hepatitis developed; the absence of hepatic disease was confirmed histopathologically. The copper that accumulated in the liver of the rats was thought to exist in the form of divalent ions, which were suspected of reducing the T1 and T2 of neighboring protons. However, the signal intensities of the liver on T1- and T2*-weighted images did not change, suggesting that in vivo copper, even when accumulated abnormally, does not influence the signal intensity of MR images.     

Techniques for high-resolution MR imaging of atherosclerotic plaque

Atherosclerotic cardiovascular disease is the most common cause of death in the United States. Investigation of atherosclerotic plaque morphology and composition is important because the findings may be useful in predicting prognosis or response to therapy. This study presents high-resolution magnetic resonance (MR) imaging techniques developed on a 1.5-T whole-body imager with a custom-built surface coil, for characterizing the composition and morphology of plaque removed at carotid endarterectomy. The initial comparison of MR imaging and histologic results showed good correlation. In conjunction with MR angiography, these techniques could be used in in vivo imaging to define the size, location, and contents of atherosclerotic plaque at the carotid bifurcation.     

Dynamic MRI of the gallbladder lesions: Differentiation of benign from malignant

Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions.