64层螺旋CT多向调整多平面重组对周围型肺癌征象的检出

目的 探讨64层CT多向调整多平面重组(MPR)对周围型肺癌征象的检出.方法 收集病理证实的周围型肺癌45例,64层CT胸部各向同性扫描后行肿瘤靶重建及多向调整MPR重组,并与横断薄层重建图像对比分析.结果 (1)MPR对CT支气管征、血管集束征、深分叶征、叶间胸膜凹陷征及破坏征的检出率高于薄层横断面重建图像;对细短毛刺征、叶间裂以外胸膜凹陷征的检出与横断薄层重建图像无差别.(2)MPR对空泡征和CT支气管征的判别有优势.(3)MPR对3种及以上CT征象的显示率高于横断薄层重建图像.结论 64层CT多向调整MPR有利于提高周围型肺癌征象的检出.     

16层螺旋CT重建技术诊断周围型小肺癌临床价值分析

目的 探讨16层螺旋CT重建技术在周围型小肺癌（small peripheral lung cancer,SPLC）临床诊断中的应用价值.方法 收集2010年8月～2012年12月在我院经手术及病理证实的周围型小肺癌患者进行16层螺旋CT检查及MPR、SSD、SVR重建图像并进行分析,旨在提高对其CT征像的认识与诊断正确率.结果 采用MPR重建后对分叶征、细短毛刺征、血管集束征、胸膜凹陷、空泡征等征象检出率均高于薄层扫描,但是其中MPR重建后对分叶征、细短毛刺征、血管集束征等征象检出率则明显高于薄层扫描,且差异具有统计学意义（x2 =8.05、8.25、4.61,P%0.05）.采用SVR重建后无空泡征检出,而对分叶征、细短毛刺征、血管集束征、胸膜凹陷等征象检出率均高于薄层扫描,但是其中SVR重建后血管集束征检出率则明显高于薄层扫描,且差异具有统计学意义（x2=7.01,P＜0.05）.采用SSD重建后无空泡征检出,而在显示周围型小肺癌分叶征、细短毛刺征、血管集束征、胸膜凹陷四项主要征象上敏感性均高于横断面薄层扫描,但是其中SSD重建后对胸膜凹陷检出率则明显高于薄层扫描,且差异具有统计学意义（x2=5.07,P＜0.05）.结论对SPLC进行MPR、SSD、SVR等三种不同的图像后处理,对分叶征、血管集束征及胸膜凹陷征的显示敏感性显著提高.     

64层螺旋CT多向调整多平面重组在周围型肺癌诊断中的应用

目的探讨64层CT多向调整多平面重组（MPR）在周围型肺癌诊断中的应用。方法病理证实的周围型肺癌32例,胸部扫描后行肿瘤靶重建及多向调整MPR重组与横断薄层重建图像对比。结果MPR对空泡征,深分叶征,血管集柬征的检出高于薄层重建图像。对毛刺征,胸膜凹陷征的检出与薄层重建图像无明显差别。叶间胸膜破坏征和充气支气管征的检出有明显优势。结论64层CT多向调整MPR有利于提高周围型肺癌征象的检出。     

多层螺旋CT多平面重建在周围型小肺癌诊断中的应用价值

目的探讨多层螺旋CT多平面重建在周围型小肺癌诊断中的应用价值。方法采用多层螺旋CT多平面重建（multi-plan reconstruction,MPR）技术对经手术及病理证实的周围型小肺癌患者重建图像并进行分析。结果采用MPR重建后对分叶征、细短毛刺征、血管集束征、胸膜凹陷、空泡征等征象检出率均高于薄层扫描,但是其中MPR重建后对分叶征、细短毛刺征、血管集束征等征象检出率则明显高于薄层扫描,且差异具有统计学意义（x2=9.14、10.52、3.85,P〈0.05）。采用SSD重建后无空泡征检出,而在显示周围型小肺癌分叶征、细短毛刺征、血管集束征、胸膜凹陷四项主要征象上敏感性均高于横断面薄层扫描,但是其中SSD重建后对分叶征和胸膜凹陷检出率则明显高于薄层扫描,且差异具有统计学意义（x^2=4.51、6.01,P〈0.05）。结论多层螺旋技术达到各向同性成像获得高分辨率图像,对周围型小肺癌的诊断有着重要的临床价值。     

肺内恶性结节多层螺旋CT扫描形态学的诊断价值

目的评价多层螺旋CT(MSCT)扫描形态学对肺内恶性结节的诊断价值。资料与方法69例肺内恶性结节患者行MSCT扫描,应用多种后处理技术全面了解病灶形态学特征,运用Spearman相关分析探讨病灶形态学特征与病理特征的关系。筛选出有意义的形态学征象后,与同期86例经手术证实的非恶性结节形态学数据行χ2检验,比较两组形态学征象构成比的差别。结果恶性病变中胸膜凹陷征、支气管截断征与血管聚集征出现率分别为81.8%、85.5%和95.7%;分化程度与空泡征呈显著正相关(r值为0.631),P-TNM分期与毛刺征呈显著正相关(r值为0.652),结节大小与衰减密度呈显著负相关(r值为-0.714),P值均为0.000。空泡征、短毛刺、非实性结节、胸膜凹陷征、支气管截断征与血管聚集征在恶性结节中的出现率均明显高于非恶性结节。结论多种后处理技术应用于MSCT中能全面了解病灶特征,空泡征、短毛刺、非实性结节、胸膜凹陷征、支气管截断征与血管聚集征是提示恶性结节的征象。     

周围型肺腺癌的CT表现(附36例分析)

目的 研究周围型肺腺癌的CT表现。方法 回顾性分析36例经手术病理证实的周围型肺腺癌CT表现。结果 CT扫描直接显示，36例周围型肺腺癌主要CT征象是空气支气管征、空泡征、深分叶征、血管切迹征、胸膜凹陷征、纵隔淋巴结肿大，以及远处器官转移。结论 只要对周围型肺腺癌的CT征象进行全面分析，通常可以做出正确诊断。     

多平面重建对支气管血管连接引起肿瘤切迹的检出

目的　从病理角度认识支气管血管切迹征 ,探讨多平面重建 (MPR)对该征检出的作用。方法　①观察病理证实的周围型小肺癌 91例 ,良性结节 5 5例。以及 9例周围型小肺癌 ,2例良性结节术后改良Heitzman法充气固定肺叶制成病理大切片 ,对良恶性支气管血管连接进行对比分析。②对恶性支气管血管连接 2 0例 ,良性 13例行MPR ,考察MPR显示切迹征的作用。结果　①支气管血管切迹征对恶性者特异性为 95 .2 %。②恶性支气管血管连接在MPR的切迹征检出率为 70 % ,与横断扫描之间有显著差异。结论　切迹征对于恶性支气管血管连接有高特异性诊断价值。MPR配合多层螺旋CT能提高此征检出率     

肺良恶性结节的CT表现分析

目的：探讨肺结节的CT征象与其良恶性的关系。方法：回顾性分析122例肺结节的CT表现及其手术切除后的病理类型,比较分析良恶性肺结节之间各CT征象（毛刺征、分叶征、空泡征、支气管充气征、血管集束征、胸膜牵拉征）的检出率,并用Sperman秩相关分析4种不同浸润程度的早期肺腺癌（不典型腺瘤样增生、原位腺癌、微浸润腺癌、浸润性腺癌）与3种不同密度结节（纯磨玻璃密度结节、部分实性结节、实性结节）之间的关系。结果：良性结节的毛刺征、分叶征、空泡征、血管集束征、胸膜牵拉征检出率均明显低于恶性结节（均P<0.05）,而气管充气征检出率差异无统计学意义（P>0.05）。早期肺癌的侵袭性与结节的实体成分检出率存在正相关（Sperman相关系数=0.533,P=0.000）。结论：毛刺征、分叶征、空泡征、血管集束征、胸膜牵拉征及随访过程中结节实性成分的出现及增加可作为恶性肺结节的特异性CT征象。     

螺旋CT薄层扫描对肺内孤立小结节的诊断价值

目的:评价螺旋CT薄层扫描诊断肺内孤立小结节(sSPN)的价值。材料和方法:收集80例经手术病理证实的直径≤2cmsSPN,其中恶性肿瘤31例,炎性结节及结核结节各20例,良性肿瘤9例,所有病例均行常规及薄层平扫加增强扫描,分析sSPN的CT征象。结果:螺旋CT薄层扫描能显示常规扫描不能显示的部分细小钙化、毛刺征、空泡征、棘状突起及脂肪等,对sSPN有较大鉴别诊断价值的CT征象是毛刺征、分叶征、空泡征、钙化及胸膜凹陷征。增强扫描,恶性sSPN强化明显,多呈均匀强化,增强前后CT净增值大于20Hu;良性sSPN多数强化不明显,增强前后CT净增值小于20Hu(除炎性假瘤及血管瘤外),结核结节及肺囊肿呈环状强化,其余良性结节多呈均匀强化。结论:对于sSPN,螺旋CT薄层扫描比常规扫描能显示更多细微CT征象,是目前最有效的检查方法,有助于sSPN定性诊断。     

多层螺旋CT征象诊断周围型非小细胞肺癌的临床研究

目的探讨多层螺旋CT征象在周围型非小细胞肺癌（non-small cell lung cancer,NSCLC）临床诊断中的应用价值。方法选择在我院经手术及病理证实的周围型非小细胞肺癌患者进行多层螺旋CT检查、多平面重建（multi-plan reconstruction,MPR）、表面遮盖显示（shaded surfaee display,SSD）、遮盖容积再现（shaded volume rendering,SVR）重建图像并进行分析,旨在提高对其CT征像的认识与诊断正确率。结果采用MPR重建后对分叶征、毛刺征、血管集束征、胸膜凹陷征、空洞征、胸膜受侵征等征象检出率均高于薄层扫描,但是其中MPR重建后对分叶征、毛刺征、血管集束征等征象检出率则明显高于薄层扫描,且差异具有统计学意义（X^2=4．05、4．66、4．61,Pd0．05）。采用SVR重建后无空洞征检出,而对分叶征、毛刺征、血管集束征、胸膜凹陷征、胸膜受侵征等征象检出率均高于薄层扫描,但是其中SVR重建后血管集束征检出率则明显高于薄层扫描,且差异具有统计学意义（X^2=7．O1,Pd0．05）。采用SSD重建后无空洞征检出,而在显示周围型非小细胞肺癌分叶征、毛刺征、血管集束征、胸膜凹陷征、胸膜受侵征等主要征象上敏感性均高于横断面薄层扫描,但是其中SSD重建后对胸膜凹陷征检出率则明显高于薄层扫描,且差异具有统计学意义（X^2=5．07,P〈O．05）。结论对周围型非小细胞肺癌患者进行MPR、SSD、SVR等三种不同的图像后处理,对分叶征、血管集束征及胸膜凹陷征征的显示敏感性显著提高。     

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.     

Controversies in cervical spine imaging in trauma patients

No area of emergency radiology has generated as much discussion in recent years as the subject of cervical spine imaging for trauma patients. This review will be in three parts. The first will examine the indications for cervical imaging and will focus on those factors that make patients at high risk or low risk for cervical injury. The second part will discuss the merits of radiography and computed tomography as the main screening diagnostic examination. In addition to the roles of each modality in the evaluation process, such factors as efficacy of diagnosis, time (duration) of study, and cost will be discussed. Finally, the third part will explore the methods currently employed to clear the cervical spine in comatose patients.Presented at the Annual Meeting of the American Society of Emergency Radiology, Las Vegas, Nevada, 22–25 October, 2003     

Uterine contractions: Possible diagnostic pitfall at MR imaging

A total of 206 nongravid patients with various gynecologic problems underwent pelvic magnetic resonance (MR) examinations that included both sagittal T2-weighted and contrast agent–enhanced T1-weighted images. MR images were retrospectively reviewed to identify changes in endometrial configuration on serial images obtained during the same MR examination. In 20 MR examinations (all in women of reproductive age), endometrial distortion due to myometrial bulging was noted on T2-weighted or contrast-enhanced T1-weighted images. It was absent on other MR images obtained at different times. Myometrial bulging exhibited low signal intensity in 18 examinations. The finding resembled adenomyosis or leiomyoma on T2-weighted or contrast-enhanced T1-weighted images. These results evidence the presence of transient myometrial bulging and transient low-intensity myometrium in the nongravid uterus. This phenomenon is thought to represent uterine contraction. Clinicians should be aware of the potential presence of transient low-signal-intensity myometrial bulging that could present diagnostic problems in the normal uterus.     

Brodie Abscess: MR imaging appearance in 10 patients

The magnetic resonance (MR) imaging features of Brodie abscess have not yet been fully evaluated. Ten patients with Brodie abscess, eight of long bone and two of vertebra, were studied with MR imaging. Long bone abscess had a characteristic “target” appearance with four layers: (a) a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR (short-inversion-time inversion recovery) images, (b) an inner ring isointense to muscle on T1-weighted images and with high signal intensity on T2-weighted and STIR images, (c) an outer ring hypoin-tense on all images, and (d) a peripheral halo hypointense on T1-weighted images. In six of eight cases, a soft-tissue mass was found. The two vertebral abscesses had a less specific appearance, with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR images. Only the peripheral halo was clearly identified in both cases.     

Right-side aortic arch with aneurysm of aberrant left subclavian artery: MR imaging appearance.

Reports of aneurysms of the subclavian artery in both normal and anomalous aortic arches have been rare. The authors describe a patient with a right-side aortic arch and an aneurysm of the aberrant left subclavian artery, which, to the authors' knowledge, is a previously unreported association. At presentation, the aneurysm appeared as a calcified left superior mediastinal mass. Magnetic resonance imaging enabled preoperative diagnosis and guided surgical planning.     

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.     

Adrenal tissue characterization with 0.5-T MR imaging: Value of T2*-weighted images

The authors investigated the value of magnetic resonance (MR) imaging at 0.5 T for distinguishing adrenal adenomas from adrenal metastases. The series included 23 adrenal adenomas (18 nonhyperfunctioning, five hyperfunctioning) and 23 adrenal metastases from various organs. Adrenal tumor–liver signal intensity ratios on T1-, T2-, and T2*-weighted images were calculated for adrenal tissue characterization. Adrenal adenomas were more precisely distinguished from adrenal metastases on T2*-weighted images (21 of 23, 91%) than on T2-weighted images (15 of 23, 65%). T1-weighted images were not useful for this distinction. In conclusion, T2*-weighted images were better than routine T2-weighted images for distinguishing adrenal adenomas from adrenal metastases. It can be postulated that the total signal intensity of adrenal adenomas, which contain some fat components, decreased on T2*-weighted images because of an out-of-phase effect.     

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.