结节性甲状腺肿的MR表现与病理对照

目的 探讨MR对结节性甲状腺肿(NG)的诊断价值.方法 回顾性分析55例NG患者的MR表现,观察结节的大小、数量、形态、边缘、信号类型、强化方式,结果与手术病理对照.结果 55例NG共见110个结节,其中单个结节19例(34.5%),多个结节36例(占65.5%);边界清晰、规则101个(91.8%),边缘模糊、不规则9个(8.2%);实性结节64个(58.2%),囊性结节46个(41.8%);结节 有4种信号类型:(1)T1WI等或稍高信号、T2WI高信号58个(52.7%);(2)T1WI和T2WI均高信 号37个(33.6%);(3)T1WI稍低、等或高信号、T2WI低信号9个(8.2%);(4)T1WI和T2WI均等信号6个(4.5%);绝大多数实性结节强化明显,幅度高于背景甲状腺;囊性结节呈周围环形强化、壁结节明显强化和囊内不强化.结论 NG在MR像上具有一定的形态学和信号特征,了解其MR表现有助于明确诊断.     

肝硬化结节与小肝癌的MRI研究

目的:回顾性分析肝硬化合并小肝癌、再生结节(RN)及肝不典型增生结节(DN)的MR表现,探讨其MR诊断与鉴别诊断。方法:收集50例结节性肝硬化病例MR检查资料,患者行正反相位T1WI、脂肪抑制T2WI、动态增强扫描和弥散加权(DWI)扫描,总结肝内结节的信号特点。结果:RN在T1WI脂肪抑制上多为等信号或稍高信号,T2WI多为低信号,增强后与周围正常肝组织强化相似或信号稍低;DN在T1WI多为较高信号,T2WI多为稍低或等信号,增强后强化不明显;癌结节T1WI多为稍低或等信号,偶有稍高信号,T2WI多为较高信号,DWI为高信号,强化多为动脉中晚期强化,门静脉期以后强化减退。结论:磁共振平扫加动态增强能对大多数RN、DN和小肝癌结节做出明确诊断和鉴别。     

结节性硬化症脑部CT和MRI表现(附12例报告)

目的:分析结节性硬化症脑部CT和MRI表现,以提高对本病的认识。方法:回顾性分析12例经临床证买为结节性硬化症患者的CT和MRI脑部影像学表现。结果:TSC脑部主要影像学改变包括:①室管膜下结节(12例),CT 上表现为多发高密度钙化结节,MRI上表现为T1WI高信号、T2WI低信号7例,T1WI和T2WI上均为低信号1例,T1WI 上呈等信号、T2WI上呈低信号4例;②皮层及皮层下结节(9例),其CT表现为高密度钙化灶3例、低密度灶6例,MRI上呈T1WI低信号、T2WI高信号9例;③脑白质异常(6例),CT上表现为多发低密度灶4例,MRI上表现为T1WI低信号、 T2WI高信号6例。5例行MRI增强扫描,示室管膜下结节呈中等强化,皮层及皮层下结节和脑白质异常信号均未见强化。结论:CT和MRI能较好显示结节性硬化脑部改变,CT对显示钙化结节较敏感,MRI对显示皮层及皮层下结节和脑白质改变较敏感。     

甲状腺结节的磁共振灌注成像诊断

目的:探讨MR灌注加权成像(PWI)在甲状腺结节定性诊断中的价值.方法:62例经病理证实的甲状腺结节病变患者纳入研究,年龄26～76岁,平均52岁,其中良性结节52例,恶性结节10例.在完成常规扫描(SE序列,横断面T1WI和T2WI平扫)后,进行PWI扫描,团注Gd-DTPA(浓度0.5mmol/ml,用量0.2mm...     

结节性硬化的MRI诊断

目的：报导11例脑结节性硬化并总结本病MRI特点。材料和方法：11例儿童结节性硬化患者。年5个月～14岁.均以癫痫为主要症状就诊，8例合并皮肤病变．2例胸部和肾脏分别受累，4例智力低下。采用Toshiba 0.35T超导型MRI系统以自旋回波T3加权T1 WI)500／25及T2加权(T2 WI)2000／80．横断面及矢状面平扫，层厚5-10mm.结果：MRI特点：(1)室管膜下结节11例，共55个结节．以侧脑室外侧壁分布最多51个，第三脑室旁1个，第四脑室旁3个，T1 WI上结节与脑实质呈等信号．与脑脊液形成对比，是发现室管膜下结节的最好办法。(2)皮层与皮层下结节10例，9例分布于额顶叶，1例以脑干小脑为主。在T1WI及T2Wl上结节均呈等信号．但在T2WI上结节周围有高信号环围绕（7例70%)具诊断特征性。结论：脑结节性硬化MRI检查中有典型征象，在本病协断中起重要作用。     

ADC直方图分析法鉴别中央带前列腺癌与T2WI低信号增生结节的研究

目的:探讨表现扩散系数(ADC)直方图分析法鉴别诊断中央带前列腺癌和T2 WI低信号增生结节的效能.方法:回顾性分析29例中央腺体(CG)前列腺癌患者(前列腺癌组)和24例T2WI低信号增生结节患者(增生结节组)的MRI图像,所有患者行磁共振DWI检查,b值为0、1000 s/mm2.在MR上确定前列腺癌和增生结节病灶,并与病理结果对照.计算并比较两类病变的平均ADC(ADCmean)值和第10百分位数ADC值(10％ ADC).用受试者工作特性曲线(ROC)分析10％ ADC和ADCmean鉴别CG前列腺癌与T2 WI低信号增生结节的效能.结果:共计32处前列腺癌病灶和28处增生结节纳入研究,增生结节的10％ ADC和ADCmean值分别为(0.81±0.14)×101、(1.03±0.17)×10-3mm2/s,前列腺癌10％ ADC和ADCmean值为0.64±0.12和0.83±0.15,均明显低于增生病变(P＜0.05).10％ADC值鉴别前列腺癌和增生结节的ROC曲线下面积(AUC)为0.87,明显高于ADCmean(0.81) (P＜0.05).结论:表观扩散系数直方图有助于提高中央带前列腺癌与T2 WI低信号增生结节的鉴别诊断.     

结节性硬化症的CT和MRI特点

目的:分析结节性硬化症颅内结节分布特征;比较磁共振T2WI与FLAIR序列对颅内结节的显示能力.方法:计数40例患者各个脑叶结节数量,用SPSS 11.5软件比较颅内结节在各脑叶的数量差异;Siemens Trio 3.0T核磁共振仪扫描其中16例, 测量T2WI和FLAIR未钙化结节总体积,比较二者差异.结果:CT和MRI显示本组患者均存在室管膜下结节,MRI显示85%患者存在皮层及皮层下结节;χ2检验P(双侧)=0.49,表明结节在各脑叶数量无差异;配对T检验P(双侧)=0.001,表明T2WI与FLAIR测得结节总体积具有显著差异.结论:结节在各脑叶的数量无差异;FLAIR比T2WI更能敏感检出结节.     

卵巢甲状腺肿的MDCT和MRI表现

目的分析卵巢甲状腺肿(struma ovarii,SO)的多排螺旋CT(MDCT)和MRI表现,总结具有诊断价值的征象。方法回顾性分析经手术病理证实的10例SO患者的临床资料及MDCT和MRI表现,其中2例同时行CT和MRI检查,图像分析包括病灶数目、位置、大小、形态、边界、密度、囊实性比例、强化幅度等。结果10例SO均为单发附件区囊实性肿块,9例为多房囊实性肿块,3例伴高密度囊腔,MRI显示大部分囊性成分T1WI为低信号,T2WI为高信号,其中1例含高密度的囊液在T2WI呈极低信号;6例病灶实性为主,平扫肿瘤边缘显示欠清,增强后轮廓清晰伴实性病灶明显强化(CT增强幅度平均87.5HU)。此外,9例伴有盆腔积液;3例伴钙化,表现为实性区及囊壁簇状、蛋壳样钙化;4例合并同侧成熟畸胎瘤。结论SO的MDCT及MRI表现具有一定的特征,当病灶内高密度囊液在T2WI呈极低信号、实性成分明显强化同时合并成熟畸胎瘤时,应考虑到SO可能。     

代偿期肝硬化MRI常规序列形态学分析和信号测量研究

目的 :探讨MRI常规序列形态学分析和信号测量对代偿期肝硬化的诊断价值。方法 :回顾性分析184例代偿期肝硬化患者(实验组)的上腹部MRI常规T1WI、FS-T1WI、T2WI和FS-T2WI图像,测量其信号强度,并与125例正常人(对照组)进行比较。结果:代偿期肝硬化T1WI及FS-T1WI示肝实质有稍高或高信号小或细小结节139例(75.54%);T2WI、FS-T2WI示肝实质有低信号小或细小结节78例(42.39%);肝脏表面不光滑,呈大小不等结节状或波浪状改变105例(57.07%);肝裂增宽58例(31.52%);肝叶比例失调86例(46.74%);肝脏缩小43例(23.37%);脾大156例(84.78%);门静脉高压征象15例(8.15%),包括门静脉、脾静脉增粗以及食管下段、胃底等静脉曲张。肝脏信号强度T1WI及FS-T1WI实验组显著低于对照组(P<0.05),T2WI及FS-T2WI显著高于对照组(P<0.05)。结论 :MRI常规序列形态学分析对代偿期肝硬化的诊断敏感且操作简便;肝脏信号强度在某种程度上可反映代偿期肝硬化肝脏的病理变化。     

磁共振增强扫描应用菲立磁在诊断肝硬化大结节及其癌变中的价值初探

目的　探讨菲立磁肝脏增强扫描在诊断肝硬化大结节及其早期癌变中的诊断价值。方法　肝硬化大结节患者 9例 ,共11个结节 ,行菲立磁肝脏增强扫描 ,其中 4例 1d前注射Gd -DTPA行动态门静脉脉造影 (DCE -MRP)。结果　 6例 8个再生大结节平扫T1WI表现为高信号 ,T2 WI表现为低信号 ,菲立磁增强后肝脏实质T2 WI明显下降 ,再生大结节信号随肝脏实质同步下降表现为等信号。其中 2例行动态门脉造影均未见结节动脉期强化。 2例 2个结节平扫T1WI表现为高信号 ,T2 WI也表现为高信号 ,菲立磁增强后结节信号仍表现为高信号。该 2例均行动态门静脉造影 ,1例可见结节动脉期强化 ,实质期强化减低 ,另 1例未见动脉期强化。 1例 1个结节平扫T2 WI低信号中可见小的结节样高信号 ,呈“结中结”表现 ,菲立磁增强可见病灶中心的T2 WI高信号部分信号无降低 ,而周围的T1WI低信号部分信号降低。结论　菲立磁增强肝脏扫描在诊断肝硬化大结节及其有无早期癌变有其独特的优势     

Computed tomography pulmonary angiogram diagnosis of pulmonary embolism

Over the last decade, contrast-enhanced spiral CT has been established as a non-invasive alternative to catheter angiography and is now regarded as the first-line imaging investigation for the diagnosis of pulmonary embolism (PE). The reported sensitivities for the diagnosis of PE of spiral CT vary from 45 to 100% and the specificities vary from 78 to 100%. Prospective outcome studies have shown a high negative predictive value for a single-detector spiral CT for PE. Patients' outcomes were not adversely affected in these studies when anticoagulation was withheld after a negative CT pulmonary angiogram. The main limitation of single-detector spiral CT has been its limited ability to detect isolated subsegmental PE. However, multidetector spiral CT allows evaluation of pulmonary vessels down to sixth-order branches and significantly increases the rate of detection of PE in segmental and subsegmental levels. The interobserver correlations for diagnosis of subsegmental PE with multidetector spiral CT exceed the reproducibility of selective pulmonary angiography. If appropriate equipment is available (multidetector CT), then CT pulmonary angiogram is safe to be used as the first-line imaging investigation for the diagnosis of PE.     

MR imaging of pulmonary arterial hypertension and pulmonary emboli

Intraluminal signal in the pulmonary arteries on spin-echo, ECG-gated MR images is limited to the diastolic phase of the cardiac cycle in normal subjects. Initial experience has indicated that signal persisting during systole may be characteristic of slow blood flow associated with pulmonary arterial hypertension (PAH) or of thrombotic material secondary to pulmonary embolism. This study analyzes our cumulative experience (31 patients) with multiphasic, double spin-echo MR for assessing PAH and/or suspected pulmonary embolism. In PAH, the abnormal systolic signal showed an intensity increase from first to second echo. This pattern was observed in 92% of PAH patients, including 100% of patients with pulmonary systolic pressures greater than or equal to 80 mm Hg and 60% of patients with pressures less than 80 mm Hg. At any focus in the pulmonary arteries, such signal disappeared at some phase of the cardiac cycle. In patients with pulmonary embolism, signal from thrombus was fixed throughout the cardiac cycle and showed little or no increase in relative intensity change from first- to second-echo image. Using this guideline, MR made six confirmed positive and four confirmed negative diagnoses of proximal pulmonary embolism, while it failed to identify thrombus in the one patient with a peripheral pulmonary embolism. Intraluminal signal in the pulmonary arteries caused by PAH or pulmonary embolism can be differentiated in most instances using multiphasic, double spin-echo, ECG-gated MR. However, at its current stage of development, the procedure does not appear to be useful for the evaluation of peripheral pulmonary embolism.     

肺灌注/通气显像与肺动脉造影诊断肺动脉栓塞的对比研究

目的评价核素肺通气/灌注(V/Q)显像在肺动脉栓塞(PE)诊断中的价值。方法临床疑有PE患者30例,男女各15例,平均年龄(38.2±13.9)岁。均行胸部X线片检查、核素V/Q显像和肺动脉造影。11例患者在行肺灌注显像时,选择双侧足背静脉注射肺灌注显像剂,同时完成双下肢静脉显像。结果30例患者中22例V/Q显像示不相匹配的肺叶、肺段或多发亚肺段的放射性分布稀疏或缺损,提示为PE;但肺动脉造影证实22例中20例为PE。8例患者的V/Q显像为相匹配的肺叶、肺段或多发亚肺段的稀疏或缺损,提示不是PE,与肺动脉造影结果一致。核素V/Q显像诊断PE的灵敏度为100%（20/20例）,特异性为80.0%（8/10例）,准确性为93.3%（28/30例）。X线胸片和核素下肢静脉显像有助于PE的正确诊断。结论多数PE患者通过核素肺V/Q显像结合X线胸片可以作出明确诊断,少数肺V/Q显像与临床表现不符的患者需行肺动脉造影。     

胸腔镜肺叶切除术治疗肺良性疾病的临床分析

目的探讨胸腔镜肺叶切除术治疗肺部良性疾病的可行性和临床应用价值。方法回顾我院2010年3月～2012年7月采用胸腔镜肺叶切除术治疗的37例肺良性疾病的临床资料,对手术方式和围术期相关临床指标进行分析。结果37例患者中,全胸腔镜手术28例,胸腔镜辅助小切口手术9例。平均手术时间178(55～275)min;术中出血平均420(30～1300)ml;术后总引流量平均1420(160～4800)ml;术后住院时间平均9.5(4～27)d。全组无围术期死亡,术后并发呼吸衰竭1例,肺持续漏气1例,其余无严重并发症。结论胸腔镜肺叶切除术治疗肺部良性疾病是安全可行的,对于有肺叶切除适应证的肺部良性疾病患者,可以作为主要的手术方式。     

Follow-up pulmonary perfusion scintigraphy pulmonary arterial embolization in two cases of familial pulmonary arteriovenous fistula

Follow-up pulmonary perfusion scintigraphy in evaluating pulmonary arterial embolization were assessed by two cases of pulmonary familial arteriovenous fistula. Pulmonary arteriovenous fistula was found for brain abscess in the older brother, and for dyspnea on effort in the younger brother. Pulmonary arterial embolizations were performed. (older brother: 4 times, younger brother: 5 times) Before embolization, pulmonary perfusion scintigram showed pale defect, clear asymmetric perfusion between right and left lung, and clear renal visualization. On the other hand, after the embolization, clear multiple defects agreed with the sites of embolization, and asymmetric pulmonary perfusion and renal visualization disappeared. We conclude that follow-up pulmonary perfusion scintigraphy is useful to evaluate in pulmonary arteriovenous fistula after embolization.     

Virtual pulmonary arterioscopy in pulmonary embolic disease

16 slice multidetector CT provides virtual endoscopic views of the inside of arteries, or any other hollow structures. This is performed non-invasively using post-processing of three-dimensional isotropic image data sets, acquired during standard CT examinations. These virtual endoscopic views are simultaneously correlated with the standard multiplanar reconstructions, with the ability to navigate a virtual camera through the hollow structure under study. Normal and abnormal volume rendered images of the pulmonary arteries are presented in correlation with the multiplanar reformats. The abnormal images show the volume rendered appearances of acute and chronic pulmonary embolic disease. It is also postulated that this technique has a problem solving role in the differential diagnosis of chronic mural emboli from extravascular structures such as adjacent lymph nodes or bronchiolar impaction. This technique may also have a role in medical education, providing clinicians and medical students with interactive three-dimensional representations of disease processes.