64层MSCTA对急性自发性蛛网膜下腔出血病因诊断价值分析

目的：探讨64层螺旋CT血管成像在急性自发性蛛网膜下腔出血病因的诊断价值和临床应用。方法：收集临床拟诊急性自发性蛛网膜下腔出血患者进行64层螺旋CT血管造影检查,并将检查结果与DSA或手术结果进行对照研究。结果：本组69例患者中CTA诊断动脉瘤53例59个,其中5例为多发,DSA发现53例动脉瘤共59个,CTA漏诊、误诊动脉瘤各1例;诊断动静脉畸形5例,DSA和手术均证实为5例,另外还有3例烟雾病得到DSA证实。其中8例为阴性。MSCTA蛛网膜下腔出血病因诊断敏感性、特异性、阳性预测值和阴性预测值分别为98.6%,88.9%,98.6%,88.9%;MSCTA和DSA对动脉瘤长径、囊颈比（瘤体短轴/瘤颈）的评价方面无统计学差异（P〉0.05）,但对囊颈比整体存在评价过低情况,易把窄颈动脉瘤评价为宽颈动脉瘤。结论：64层CTA能准确、迅速地评价急性自发性SAH,为临床诊治提供科学的依据和指导,降低患者的致残率和死亡率。     

64层螺旋CT分别减影脑动脉混合脑动静脉和脑静脉血管成像在颅内自发性出血术前评估的价值

目的：探讨64层螺旋CT分别减影脑动脉、混合脑动静脉、脑静脉血管成像在自发性颅内出血术前评估价值。方法回顾分析同时行CT血管造影（CTA）和数字减影血管造影（DSA）检查的自发性颅内出血患者共215例。 CTA检查全部行64层螺旋CT平扫、增强动脉早期和静脉早期扫描,将动、静脉早期数据减去平扫数据分别重建动脉及混合动静脉,静脉早期数据减去动脉早期数据重建静脉。结果减影脑动脉、脑静脉血管图像去除了颅骨并且动脉、静脉无相互干扰,分别清晰显示动脉或静脉病变,混合脑动静脉则去除颅骨干扰且同时显示脑动静脉病变。215例颅内出血患者中14例CTA和DSA检查颅内均未见畸形血管,2例动脉瘤DSA发现而CTA未显示,3例动脉瘤CTA发现而DSA未显示。 CTA和DSA共同显示畸形血管196例,敏感性为99．9％,特异性为82．4％,其中动脉瘤179例,动静脉畸形9例,静脉瘤3例,烟雾病5例。结论64层螺旋CT分别减影脑动脉、混合脑动静脉、脑静脉血管成像在颅内出血检查,病变及周围结构显示清楚,对临床术前评估有较大意义,值得推广应用。     

MSCT血管造影在颅内血管性疾病中的诊断价值

目的探讨16层螺旋CT血管造影(MSCTA)在颅内血管性疾病中的诊断价值。方法对339例患者行16排螺旋CT血管造影,同时采用容积重建(VR)、多平面重建(MPR)、最大密度投影(MIP)显示血管,其中45例动脉瘤、22例动静脉畸形、4例烟雾病和18例脑动脉狭窄随后进行了DSA检查或手术治疗。结果CTA诊断为动脉瘤的患者83例,动静脉畸形22例,静脉瘤2例,海绵状血管瘤3例,海绵窦动静脉瘘3例,单纯烟雾病3例,烟雾病合并动脉瘤1例,缺血性脑血管病22例,先天性变异等32例,正常病例186例,其中CTA诊断的45例动脉瘤、22例动静脉畸形、4例烟雾病和18例脑动脉狭窄与DSA检测结果及手术结果基本一致。结论MSCTA对头部血管性疾病的诊断,具有微创、快速、安全、准确性高的特点,可作为头部血管性疾病的首选影像学筛查。     

多层螺旋CT血管造影在急性自发性颅内出血中的应用价值

目的探讨多层螺旋CT血管造影(MSCTA)在急性自发性颅内出血中的应用价值。方法CT诊断急性自发性颅内出血41例,其中蛛网膜下腔出血29例、脑内血肿12例,采用容积重建(VR)和最大密度投影(MIP)方法进行MSCTA检查,并对7例颅内动脉瘤钛夹夹闭术病例和2例脑动静脉畸形、1例脑动静脉畸形伴巢内动脉瘤手术切除病例进行术后MSCTA评价。结果41例急性自发性颅内出血中,MSCTA检查出颅内动脉瘤11例、脑动静脉畸形4例、脑动静脉畸形伴巢内动脉瘤1例;MSCTA对动脉瘤的瘤体大小、瘤颈、载瘤动脉和脑动静脉畸形的部位、大小、瘤巢的形态、供血动脉和引流静脉的显示均较清楚。7例动脉瘤行钛夹夹闭术和2例脑动静脉畸形、1例脑动静脉畸形伴巢内动脉瘤行手术切除,手术所见与术前MSCTA表现相符;术后行MSCTA复查,显示夹闭动脉瘤之钛夹位置正常,载瘤动脉、颅内大血管通畅,脑动静脉畸形之瘤巢已切除。结论MSCTA是急性自发性颅内出血病因诊断的一种无创伤、快捷有效的影像学方法,并且在颅内动脉瘤、脑动静脉畸形术后评价方面也具有临床应用价值。     

64层MSCTA对蛛网膜下腔出血病因的诊断

目的：探讨64层螺旋CT血管成像（MSCTA）在自发性蛛网膜下腔出血的临床应用价值。方法：搜集临床拟诊为蛛网膜下腔出血患者76例,行64层螺旋CT血管成像检查,并将结果与DSA结果、手术结果相对照。结果：本组76例患者中CTA诊断动脉瘤28例,DSA发现29例,手术证实29例;诊断为动静脉畸形3倒,DSA发现3例,手术证实3例。有45例CTA检查未见异常发现,其中1例动脉瘤CTA漏诊。结论：64层螺旋CT血管成像可作为自发性蛛网膜下腔出血病因诊断方法之一。     

双能量CT头颅血管成像的影像质量、辐射剂量及初步临床应用

目的 探讨双源CT(DSCT)双能量技术头颅血管成像的初步临床应用价值.方法 选择41例临床怀疑有脑血管病变患者行双能量CTA(DECTA),另选择对照组41例患者行常规减影CTA.2名医师共同进行分析协商,评价两种方法颅底及颅内血管影像质量,计算辐射剂量,分析DECTA对41例患者的检查情况,选取经DSA证实的9例12个动脉瘤,测量动脉瘤的大小、瘤颈,并与DSA进行比较.DECTA和常规减影CTA血管影像质量的比较采用独立样本的非参数等级检验,辐射剂量的比较采用两个独立样本的t检验,DECTA和DSA显示动脉瘤的大小、瘤颈的比较采用配对t检验,DECTA和DSA测量动脉瘤颈、瘤长轴及瘤短轴的相关性采用Spearman相关分析.结果 颅内血管DECTA和常规减影CTA影像质量5分的病例分别占70.7%(29/41)、75.6%(31/41),差异无统计学意义(Z=-0.455,P=0.650),而颅底血管常规减影CTA总的影像质量优于DECTA(Z=-4.087,P=0.000),主要是岩段和虹吸段的影像质量较差;DECTA和常规CTA总辐射剂量分别为(396.54±17.43)、(1090.95±114.29)mGy·cm;DECTA所用总辐射剂量较常规减影CTA总辐射剂量降低了64%,差异有统计学意义(t=-38.52,P=0.000).41例临床怀疑有脑血管病变患者,DECTA检出19例患者有动脉瘤,2例动静脉畸形,3例烟雾病,17例阴性患者.9例动脉瘤患者(12个动脉瘤)、2例脑动静脉畸形、3例烟雾病和2例阴性患者行DSA或手术证实,诊断符合率达100%.DECTA检测动脉瘤颈、瘤长轴及瘤短轴分别为(2.90±1.61)、(5.23±1.68)及(3.83±1.69)mm,DSA检测动脉瘤颈、瘤长轴及瘤短轴分别为(2.95±1.71)、(5.10±1.60)及(3.83±1.65)mm.两者在动脉瘤大小、瘤径测量方面的差别无统计学意义(瘤颈、瘤长轴及短轴所对应的t值分别为-0.734、1.936及0.125,P值分别0.482、0.085及0.903);且两者测量之间有很好的相关性(瘤颈、瘤长轴及短轴的r值分别为0.964、0.976、0.973,P值均为0.000).结论 相对于常规减影CTA,颅内血管DECTA的图像质量没有明显下降,而颅底血管,尤其是岩段和虹吸段的影像质量较差.双源CT双能量CTA明显减少患者辐射剂量,有很高的诊断准确性,是一种较好的影像学检查手段.     

CTA与MRA诊断动脉瘤及评估动脉瘤破裂风险的比较

 目的 比较CT血管造影术(CT angiography,CTA)与磁共振血管造影(magnetic resonance angiography,MRA)诊断动脉瘤与动脉瘤破裂的风险评估价值。方法 48例高度怀疑为颅内动脉瘤患者随机分为两组,每组24例,记为Ⅰ组和Ⅱ组,其中Ⅰ组行CTA+DSA检查,Ⅱ组行MRA+DSA检查。比较CTA及MRA对颅内动脉瘤的诊断灵敏度、诊断特异性、阳性预测值、阴性预测值及准确率。比较CTA及MRA对5 mm以上动脉瘤的诊断价值。结果 MRA诊断颅内动脉瘤的诊断灵敏度、诊断特异性、阳性预测值、阴性预测值、准确率较CTA稍低,但二者差异无统计学意义。CTA与三维增强MR血管成像(3D CE-MRA)对5 mm以上动脉瘤的诊断能力相当,但与三维时间飞跃法MR血管成像(3D TOF MRA)相比,CTA与CE-MRA的诊断灵敏度、诊断特异性、阳性预测值、阴性预测值、准确率明显较高,差异有统计学意义(P<0.05);CTA能更清楚地显示瘤颈。结论 CTA和MRA可作为诊断动脉瘤与动脉瘤破裂的风险评估的首要手段,CTA诊断的准确率及三维形态高于MRA。     

脑血管病变115例CT血管成像分析

目的：探讨64层螺旋CT脑血管成像（MSCTA）对脑血管病变的诊断价值。方法：经64层螺旋CT脑血管成像检查的病例,使用减影方法进行后处理,得到VR、MIP图像,原始图像重建得到MPR、CPR图像,综合四种图像诊断脑血管病变,并与DSA诊断进行对照分析。结果：115例脑血管病变中,动脉瘤62例（53.91%）、动静脉畸形（AVM）6例（5.21%）、脑静脉畸形（CVM）3例（2.61%）,脑动脉狭窄或闭塞38例（33.04%）、烟雾病3例（2.61%）、海绵窦动静脉瘘2例（1.74%）、海绵状血管瘤1例（0.87%）。其中46例DSA检查结果均与MSCTA一致。结论：64层螺旋CT脑血管成像是一种安全、快速、无创的检查方法,可作为颅内血管性病变筛查和术前评估的首选检查技术。     

64排CT血管成像对自发性蛛网膜下腔出血病因的诊断价值

目的 :探讨64排CT血管成像在自发性蛛网膜下腔出血(subarachnoid hemorrhage,SAH)病因诊断中的价值。方法 :对81例临床怀疑SAH患者行CTA检查,所得原始图像由2位资深CT医师行VR、MIP、MPR等后处理,以明确病因。结果:CTA证实正常5例,动脉瘤69例,动静脉畸形7例。单个动脉瘤65例,2个动脉瘤4例。动脉瘤分布情况:前交通动脉13个,后交通动脉8个,椎-基底动脉9个,大脑前动脉9个,大脑中动脉21个,大脑后动脉4个,颈内动脉9个。囊状动脉瘤66个,梭形动脉瘤7个。大动脉瘤20个,中等动脉瘤24个,小动脉瘤29个。本组检出动脉瘤及动静脉畸形的敏感度为93.8%,特异度为98.8%。69例动脉瘤中,21例行栓塞术,48例行外科夹闭手术;7例动静脉畸形行手术切除。结论 :64排CT血管成像技术对SAH病因的诊断具有重要的应用价值。     

颅内动脉瘤320排CTA与DSA对照分析

目的 探讨320排CTA对颅内动脉瘤诊断的临床应用价值.方法 收集2010-04-2011-03期间行320排CTA和DSA检查的颅内动脉瘤患者33例.将CTA图像质量按颅底骨质残留及血管显示情况分为4个等级,再以DSA所见为对照,分析320排CTA诊断颅内动脉瘤的敏感性及粗符合率.结果 33例经320排CTA检出颅内动脉瘤30例33个、动静脉畸形(AVM)2例、颅内动脉瘤合并AVM 1例;经DSA证实有颅内动脉瘤30例33个、AVM 3例,其中动脉瘤"假阳性"1例;有22例行手术治疗.320排CTA诊断颅内动脉瘤敏感性为100%,粗符合率为97.0%.结论 与DSA比较,320排CTA诊断颅内动脉瘤有较高的敏感性及粗符合率,在术前筛查方面具有广泛的临床应用前景.     

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.     

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.     

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.     

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.