马凡综合征升主动脉病变17例影像分析

本文对17例马凡综合征患者的血管造影、CT 和MR 进行了分析,并对马凡综合征升主动脉瘤同其他原因引起的升主动脉瘤进行了比较,分别测量马凡综合征患者和其他原因引起的升主动脉瘤的窦直径、升中径、弓前径、弓中径、降上径,发现马凡综合征患者的升主动脉瘤最大直径均位于主动脉窦部,窦横径与弓前径的比值均≥1.78;而非马凡综合征患者的这一比值均明显<1.78。本文马凡综合征患者中有82%(14/17)合并主动脉瓣关闭不全。     

Pencil excitation with interleaved fourier velocity encoding: NMR measurement of aortic distensibility

A technique is presented for rapidly and noninvasively determining aortic distensibiltty, by NMR measurement of pulse-wave velocrty in the aorta. A cylinder of magnetization is excited along the aorta, wtth Fourier-veloctty encoding and readout gradients applied along the cylinder axis. Cardiac gating and data interleaving improve the effective time resolution to as high as 3 ms. Wave velocities are determined from the position of the f oot of the flow wave in the velocity profiles. Evidence of helical flow distal to the aortic arch can be seen in normal subjects, while disturbed flow patterns are visible in patients with aneurysms and dissections.     

Hybrid endograft for one-step treatment of multisegment disease of the thoracic aorta

PURPOSE: At present, a two-step surgical approach is necessary to treat patients with coexistent pathologic conditions involving the proximal and descending thoracic aorta. A hybrid endograft is described here that enables such treatment during a single operation. MATERIALS AND METHODS: The Chavan-Haverich endograft consists of a Dacron vascular prosthesis with stainless-steel stents affixed at its distal end. After approval by the institutional review board, the endograft was prospectively implanted in 22 patients with multisegment thoracic aortic disease (13 men, nine women; median age, 64 years). Eleven patients had type A dissections (one acute, 10 chronic), four had a chronic type B dissection, and seven had atherosclerotic aneurysms of the ascending aorta or aortic arch as well as of the descending aorta. Of these patients, 11 additionally required aortic valve replacement or coronary artery bypass grafting. Via median sternotomy, the aortic arch was opened in circulatory arrest. After antegrade deployment of the stent-containing portion in the descending aorta, the proximal non-stent-containing endograft was used to reconstruct the aortic arch. Median follow-up was 14 months. RESULTS: Endograft implantation was successful in all but one patient. Complications included neurologic deficits that were transient in one case and lasting in two, two cases of vocal cord paralysis, and one death. In all patients with atherosclerotic aneurysms who received the endograft (six of seven), aneurysm thrombosis was noted at follow-up. In aortic dissections, partial or complete false-lumen thrombosis to the level of the stents occurred in all patients. None of the patients showed a progressive widening of the descending aorta. CONCLUSION: The Chavan-Haverich endograft enables one-step treatment of multisegment pathologic conditions affecting the thoracic aorta that otherwise would require two or more operations.     

The thoracic aorta studied by MR imaging

Thirty-three patients with a variety of disorders of the thoracic aorta (aneurysm, dissection, Marfan syndrome, coarctation/pseudocoarctation, L-transposition, and Takayasu disease) were evaluated with magnetic resonance (MR) imaging. MR imaging delineated the presence and extent of thoracic aortic aneurysms and showed the relationship of the aneurysm to arch vessels; it also demonstrated intimal flaps and individual lumina in types A and B aortic dissection. Dilation of the ascending aorta in Marfan syndrome and focal narrowing of the aorta in coarctation were well visualized. The anteroposterior and side-to-side relationships of the aorta and pulmonary artery in L-transposition were demonstrated, as were aortic wall thickening and branch vessel narrowing in Takayasu arteritis. Initial experience suggests that MR imaging may provide a noninvasive method for evaluating thoracic aortic disease. Limitations include inferior spatial resolution, occasional difficulty in imaging the entire region of interest in one section, lack of signal from calcifications, and inability to monitor critically ill patients.     

Dissecting aneurysm of thoracic aorta: reappraisal of radiologic diagnosis.

In a series of 24 cases of acute dissecting aneurysm of the aorta (not including Marfan's disease) the diagnosis was usually suspected on the basis of the clinical picture and plain chest roentgenograms. The most consistent clinical sign was severe pain. Absent pulses and a neurological deficit were each noted in only five patients. In many cases there was no correlation between the clinical picture and the type or the extent of the dissection. Widening of the aortic arch and obliteration of the aortic knob with displacement of the trachea to the right are the most common signs in plain chest roentgenograms. A barium swallow examination in these cases reveals an elongated compression and displacement of the esophagus by the aortic arch. Calcification in the area of the aortic arch is the exception rather than the rule in dissecting aneurysms. Angiography is essential for the definitive diagnosis of dissecting aneurysms. The diagnosis is based on the demonstration of two channels, either by the presence of a linear radiolucency separating the two lumens, or by differences in flow that present as delayed opacification or delayed washout. If only the true lumen is opacified, widening of the outer extraluminal border of the aorta or narrowing of the lumen indicates the presence of a dissection. Abnormal catheter recoil and position were helpful in only two cases, and are not informative when the false lumen is catheterized. Failure to visualize main aortic branches was not always due to involvement by the dissection. It can also be caused by reduced flow due to severe proximal compression of the main lumen. The exact location of the intimal tears is usually not demonstrated unless additional injections are made in the area assumed to contain the tear. If only the false lumen is opacified in the ascending aorta, this can be recognized by the demonstration of a blind end, by failure to visualize the sinuses of Valsalva, from flattening of the medial border of the opacified channel, and from delayed washout in the blind end.     

Aortic aneurysms: growth rates measured with CT.

Because of a lack of information about the rates of growth of aortic aneurysms, such rates in thoracic and abdominal aortic aneurysms were determined. One hundred seventy-one patients with atherosclerotic aortic aneurysm managed nonoperatively were followed up for more than 6 months with sequential computed tomography (CT). There were 211 aneurysms (thoracic aortic, 82; abdominal aortic, 129). The growth rates of thoracic and abdominal aortic aneurysms were 0.42 and 0.28 cm/y, respectively. Aneurysms at the aortic arch (n = 34) grew at a faster average rate (0.56 cm/y) than aneurysms arising at other levels, even when the rate was corrected for the initial diameter. It is recommended that thoracic aortic aneurysms, especially aortic arch aneurysms, be followed frequently with CT examination of size.     

Follow-up of patients with previous treatment for coarctation of the thoracic aorta: comparison between contrast-enhanced MR angiography and fast spin-echo MR imaging

Regular follow-up is required in patients with previous intervention for coarctation of the aorta to detect recoarctation or aneurysm formation. In this study we describe the findings encountered on routine follow-up exams and we compare the use of contrast-enhanced 3D MR angiography (CE MRA) with fast spin-echo MRI (FSE) to study the thoracic aorta after previous intervention. In 51 consecutive patients previously treated for aortic coarctation, 74 MR studies of the thoracic aorta were performed during a 2-year period using CE MRA and FSE MRI. The thoracic aorta was evaluated for abnormalities of course, caliber, shape, and pathology of side branches. The CE MRA and FSE MRI studies were evaluated side by side by consensus of two reviewers evaluating which MR technique depicted the abnormalities of the thoracic aorta the best. Of 74 exams, six clinically important abnormalities were found: four aneurysms and two restenoses. Two small pseudoaneurysms were missed on the FSE studies. Contrast-enhanced MRA was judged to visualize aortic abnormalities better than FSE (47 of 74 MR studies) especially for the transverse aortic arch, coarctation site, left subclavian artery, and aortic arch configuration. For the ascending aorta and distal descending aorta, CE MRA and FSE performed equally well. Aortic diameters measured at four levels in the first 18 MRI studies showed no significant differences in diameter when measured by FSE or CE MRA (p = not significant). Clinically important abnormalities, such as aneurysm formation and restenosis, can be present years after treatment for aortic coarctation. In the regular follow-up of these patients, CE MRA may provide additional diagnostic information compared with FSE and should be included as part of the routine exam. Received: 3 April 2000; Revised: 5 July 2000; Accepted: 7 July 2000     

Coil embolization of an anastomotic leak after ascending aorta replacement

Surgical treatment of diseases of the thoracic aorta (aneurysms, dissections, and ruptures) may be associated with serious postoperative complications. Endovascular repair of thoracic aorta pathology is less invasive and offers a therapeutic alternative in high-surgical-risk patients, particularly in the presence of previous surgical repair of the thoracic aorta. The endovascular procedure, however, is almost only possible in the descending thoracic aorta, although advances have also been made in the aortic arch as well as in the ascending aorta with branched stent grafts. We report a case of a surgically treated aneurysm in the ascending thoracic aorta complicated with an anastomotic leak. If a short prosthesis (6 cm) had been available, the anastomotic leak would have been treated with endovascular repair. In lack of this prosthesis, we were forced to treat the patient with a method not generally accepted--embolization with endovascular coils--successfully resulting in occlusion of the leakage.     

主动脉夹层动脉瘤的血管内支架治疗

目的评价血管内支架置入治疗主动脉夹层动脉瘤的安全性和临床疗效。方法48例Stanford B型主动脉夹层动脉瘤患者行腔内修复术。所有患者在DSA下行左肱动脉穿刺插管、造影,了解主动脉真、假腔,夹层裂口及其与重要血管分支位置关系。腹股沟区纵切口显露股动脉,送入人工血管输送器至病变处,准确定位后,释放人工血管进行腔内修复。术后复查造影,观察真、假腔血液动力学变化,内脏及下肢动脉供血的改变。结果48例患者一次性成功置入人工血管支架,2例支架未能完全封堵漏口,内漏明显,手术成功率95.8%。支架置入后假腔血压下降,机体脏器缺血状况改善,临床症状好转或消失。结论支架性人工血管腔内修复术治疗主动脉夹层动脉瘤安全可行、效果明显,值得临床进一步推广。     

平板旋转血管造影及三维重组在主动脉病变中的应用

目的:评价平板旋转血管造影及三维重组在主动脉病变临床应用的价值.方法:对比分析31例主动脉病变患者的CT或MR、二维血管造影、旋转血管造影及三维重组影像学资料,并对其结果对比分析.31例均为男性,年龄18～81岁,平均56.5岁.结果:行胸主动脉造影28例,发现主动脉夹层25例,动脉瘤1例,假性动脉瘤1例,主动脉弓畸形1例.行腹主动脉造影3例,发现动脉瘤2例,1例为腹主动脉动脉硬化性改变并主动脉钙化.所有主动脉夹层、真性及假性动脉瘤造影与CT或MRI对比,病变的形态、大小、位置均相符.其中有2例夹层的造影提示CT诊断破口位置错误.1例主动脉弓畸形,CT误诊为动脉瘤,而造影则可以清晰显示扩张纡曲的畸形主动脉弓.其中23例主动脉夹层和3例真性动脉瘤造影后进行支架主动脉腔内隔绝术的介入治疗,术后均行二维血管造影,支架位置准确,隔绝效果良好,没有出现并发症.结论:平板旋转血管造影及三维重组对主动脉病变的诊断和治疗有较高的临床应用价值,可以提高介入治疗的安全性和成功率.     

Pitfalls in the plain film evaluation of the thoracic aorta: The mimicry of aneurysms and adjacent masses and the value of aortography

In five instances, transverse aortic arch aneurysms were found that had initially, clinically and radiographically, mimicked thoracic neoplasms. Transverse aortic arch aneurysms display a wide spectrum of presentation: they may be asymptomatic, or they may cause symptoms secondary to esophageal, bronchial, vascular, or neural compression within the mediastinum and so mimic neoplasms. Conventional radiography in four projections and tomography are important components of the diagnostic evaluation of middle mediastinal masses. However, because plain film analysis is unable confidently to distinguish selected uncalcified aortic arch aneurysms from neoplasms, thoracic aortography is essential to the diagnosis. “There is no disease more conducive to clinical humility than aneurysm of the aorta” Osler [12] Partially supported by a grant from the National Institute of Health No. 1 TO 1 HL05966-03 CAR Presented at the 61st Annual Meeting of the Radiological Society of North America, Inc., Chicago, Illinois on Tuesday, December 2, 1975     

Right Cervical Aortic Arch and Pseudocoarctation of the Aorta Associated with Aneurysms and Steal Phenomena: US,CTA, and MRA Findings

A 55-year-old woman presented with right cervical aortic arch with pseudocoarctation of the aorta further complicated by the presence of multiple aneurysms and a high-grade stenosis at the origin of the left subclavian trunk from the aorta causing a discrepancy in blood pressure between the right and left arms. The branching pattern and the resulting complex steal syndromes involving the left carotid and the subclavian system are unique. The computed tomography angiography, magnetic resonance angiography, and Doppler ultrasound findings are described.     

MR imaging of age-related dimensional changes of thoracic aorta

Changes in the dimensions of the thoracic aorta with age were studied in 70 healthy volunteers between the ages of 10 and 83 years. Spin echo images were acquired at end-diastole in three oblique planes through the ascending aorta, aortic arch, and descending aorta. A double oblique image through the whole of the thoracic aorta was also acquired. Measurements of aortic cross-sectional area and length were corrected for body surface area, and normal magnetic resonance standards were established. The direct correlation that aortic dimensions have with age is likely to be due to loss of elasticity. The ratio between areas of the ascending aorta and the aortic arch is directly related to age whereas the ratio between the aortic arch and the descending aorta is inversely related to age.     

双桶注射器盐水冲洗在MSCT主动脉成像应用价值研究

目的:探讨团注低剂量对比剂后双桶生理盐水冲洗法对MSCT主动脉成像的临床应用价值.方法:对67例临床上怀疑主动脉瘤的患者行MSCT血管成像.其中38例(第一组)注入60 ml对比剂后用40 ml生理盐水冲洗,另外29例(第二组)注入80 ml对比剂,未用生理盐水冲洗.在升主动脉、降主动脉、腹腔干、肠系膜上动脉、髂总动脉五个兴趣区测得强化值,主动脉平均强化值、最大强化值和强化一致性(最大值与最小值差)分析比较,主动脉及其分支用二维或三维后处理方法进行显示分析.依据不同的给药部位(右侧肘正中静脉或左侧肘正中静脉)对两组图像是否存在主动脉伪影进行分析比较.结果:两组患者中主动脉各段测得的平均密度值第一组低于第二组,但二者无明显差异(P＞0.05),主动脉与远端分支(髂总动脉)强化一致程度差异有显著性意义(P＜0.05).第一组中,20例从右侧肘正中静脉给药的患者,19例(95%)主动脉及其分支无伪影;18例左侧肘正中静脉给药的患者中,3例(16%)在主动脉弓处存在少量伪影.第二组中,21例从右侧肘正中静脉给药的患者,16例(76%)升主动脉处存在不同程度的伪影;8例从左侧肘正中静脉给药的患者中100%不同程度存在升主动脉和主动脉弓处伪影.结论:双桶注射器生理盐水冲洗多层CT主动脉血管成像尽管可能存在主动脉与远端分支强化不一致的情况,但并不影响图像的诊断和视觉效果,它能有效地减少对比剂的用量并能降低上腔静脉带来的主动脉伪影.     

First Magnetic Resonance Imaging-Guided Aortic Stenting and Cava Filter Placement Using a Polyetheretherketone-Based Magnetic Resonance Imaging-Compatible Guidewire in Swine: Proof of Concept

The purpose of this study was to demonstrate feasibility of percutaneous transluminal aortic stenting and cava filter placement under magnetic resonance imaging (MRI) guidance exclusively using a polyetheretherketone (PEEK)-based MRI-compatible guidewire. Percutaneous transluminal aortic stenting and cava filter placement were performed in 3 domestic swine. Procedures were performed under MRI-guidance in an open-bore 1.5-T scanner. The applied 0.035-inch guidewire has a PEEK core reinforced by fibres, floppy tip, hydrophilic coating, and paramagnetic markings for passive visualization. Through an 11F sheath, the guidewire was advanced into the abdominal (swine 1) or thoracic aorta (swine 2), and the stents were deployed. The guidewire was advanced into the inferior vena cava (swine 3), and the cava filter was deployed. Postmortem autopsy was performed. Procedural success, guidewire visibility, pushability, and stent support were qualitatively assessed by consensus. Procedure times were documented. Guidewire guidance into the abdominal and thoracic aortas and the inferior vena cava was successful. Stent deployments were successful in the abdominal (swine 1) and thoracic (swine 2) segments of the descending aorta. Cava filter positioning and deployment was successful. Autopsy documented good stent and filter positioning. Guidewire visibility through applied markers was rated acceptable for aortic stenting and good for venous filter placement. Steerability, pushability, and device support were good. The PEEK-based guidewire allows either percutaneous MRI-guided aortic stenting in the thoracic and abdominal segments of the descending aorta and filter placement in the inferior vena cava with acceptable to good device visibility and offers good steerability, pushability, and device support.     

Aortic arch aneurysms: treatment with extraanatomical bypass and endovascular stent-grafting

Endovascular repair of thoracic aortic aneurysms is emerging as an attractive alternative to surgical graft replacement. However, patients with aortic arch aneurysms are often excluded from the target of endovascular repair because of lack of suitable landing zones, especially at the proximal ones. In this paper we describe our method for treating patients with aortic arch aneurysms using a combination of extraanatomical bypass surgery and endovascular stent-grafting.     

MSCT主动脉血流动力学分析及MSCTA的临床应用价值探讨

目的：探讨多层螺旋CT主动脉的血流动力学及MSCTA的临床应用价值。方法：采用多层螺旋CT对20例主动脉进行全程血管造影，测量主动脉5处CT值，即主动脉根部、主动脉弓部、平膈顶处、肾动脉起始处、髂总动脉分叉处。并对全程主动脉造影的MSCTA进行多平面重建(multi-planar reconstruction，MPR)、最大密度投影法(maximum intensity projection，MIP)、仿真内窥镜(virtual endoscopy，VE)、容积重建(volume rendering，VR)、表面阴影显示法(surface shadow display，SSD)重建。结果：20例主动脉全程MSCTA进行多种处理后显示主动脉夹层6例、腹主动脉瘤8例、主动脉粥样硬化症1例、右侧髂总动脉瘤1例及正常主动脉4例。主动脉各测量点平均CT值分别为主动脉根部208．05HU、主动脉弓部233．45HU、平膈顶处236．65HU、肾动脉起始处237．65HU、髂总动脉分叉处222．6HU。结论：利用MSCT可以对主动脉的血流动力学进行评价。主动脉全程的MSCTA有很大的临床应用价值。     

MR imaging of the thoracic aorta in Marfan patients

A characteristic shape of the ascending aorta has been reported in patients with Marfan syndrome. To evaluate the capability of magnetic resonance (MR) imaging to distinguish between marfanoid and other aortic aneurysms, 11 Marfan patients (group 1), eight patients with ascending aorta enlargement (group 2), and 20 normal subjects (group 3) had transverse and sagittal MR of the thoracic aorta. Aortic diameter was measured at the sinuses of Valsalva (SV), the caudal portion of the ascending aorta, the prearch region (PA), the middle arch, and the descending aorta. The ratio SV/PA was significantly greater (p less than 0.001) in group 1 compared with groups 2 and 3. The SV/PA in all Marfan patients exceeded 1.4 but was less than 1.3 in subjects of groups 2 and 3. Magnetic resonance imaging provides definitive measurements of aortic dimensions and is potentially the method of choice for establishing the diagnosis of aortic involvement in Marfan syndrome and monitoring the course of aortic enlargement.     

腹主动脉复合动脉瘤的腔内隔绝术治疗

目的：讨论复合腹主动脉病变进行腔内隔绝术（EVE）的可行性。方法：1例腹主动脉并存真性、假性和夹层动脉瘤患者，经双侧股动脉切开、肱动脉切开引入贯穿导丝，利用导丝导向技术和牵张技术成功置入模块式支架-人造血管移植物，以隔绝瘤体。结果：腔内隔绝操作技术完全成功，3个瘤体同时被隔绝，未加用任何延伸移植，未出现内漏、移位等并发症，重建血流通畅。结论：本例为EVE扩大适应证提供了经验。     

Preoperative Evaluation and Endovascular Procedure of Intraoperative Aneurysm Rupture During Thoracic Endovascular Aortic Repair

Thoracic aortic aneurysms are now routinely repaired with endovascular repair if anatomically feasible because of advantages in safety and recovery. However, intraoperative aneurysm rupture is a severe complication which may have an adverse effect on the outcome of treatment. Comprehensive preoperative assessment and considerate treatment are keys to success of endovascular aneurysm repair, especially during unexpected circumstances. Few cases have reported on intraoperative aortic rupture, which were successfully managed by endovascular treatment. Here, we present a rare case of an intraoperative aneurysm rupture during endovascular repair of thoracic aortic aneurysm with narrow neck and angulated aorta arch (coarctation-associated aneurysm), which was successfully treated using double access route approach and iliac limbs of infrarenal devices. Level 5.