Abdominal aortic aneurysm morphology in candidates for endovascular repair evaluated with spiral computed tomography and digital subtraction angiography.

PURPOSE: To analyze the morphology of abdominal aortic aneurysms (AAAs) and to study the usefulness of spiral computed tomography (CT) versus digital subtraction angiography (DSA) in the evaluation of patients for endovascular repair. METHODS: Of 133 AAA patients (120 men, mean age 67 years, range 52 to 84) evaluated preoperatively with CT imaging, 77 endograft candidates (68 men) were also assessed with intra-arterial DSA. Arterial parameters were measured on axial CT scans and angiographic films for comparison. RESULTS: Mean maximum AAA diameter was 58 +/- 11 mm (range 39 to 95). Aneurysmal neck diameter was consistently smaller on DSA than on CT (20.7 +/- 3.6 mm versus 23.0 +/ 3.5 mm, p < 0.0001). The distance from the most distal renal artery to the aortic bifurcation was longer on angiography than on CT (mean difference 10.0 mm, p < 0.0001). There was a positive correlation between the maximum AAA diameter and the AAA length (r = 0.49, p < 0.0001) and an inverse relationship between the neck length and the neck diameter (r = -0.36, p < 0.0001). No correlation was found between the maximum AAA diameter and maximum iliac diameter, angulation, or length. CONCLUSIONS: AAA anatomy varies widely and independently of the aneurysm size. Therefore, the maximum size of the aneurysm is a poor predictor of whether or not an aneurysm is suitable for endovascular repair. The discrepancy between angiographic and axial CT measurements suggests that neither alone is sufficient as a preoperative imaging technique when evaluating a patient for an endovascular graft procedure.     

Ambulatory follow-up of aortic dissection: comparison between computed tomography and biplane transesophageal echocardiography

Aim of the study was to assess the relative usefulness of transesophageal echocardiography (TEE) and X-ray computed tomography (CT) in the follow-up of patients who survived an aortic dissection. Materials and Methods. We evaluated 44 patients (age = 57±12 years) with treated aortic dissection: 14 had a De Bakey type I, 20 a type II and 1 patient a type III dissection treated surgically; 1 patient had a type I, 1 a type II and 7 a type III dissection treated medically. All entered an outpatient follow-up program with serial evaluations at 1, 6 and 12 months after initial diagnosis by dual noninvasive imaging protocol. A contrast-enhanced CT scan and a TEE with biplane probe were performed on the same day and in random order. Results. A total of 252 evaluations with both CT and TEE were considered. A completely normal study was found in 45 TEE and 48 CT evaluations. The following abnormal findings could be documented by one or both techniques: thrombus in the false lumen (TEE: n=48; CT: n=45 evaluations); intimal flap (TEE and CT: n=68); aortic dilatation (TEE and CT: n=15); pericardial effusion (TEE and CT: n=3); aortic pseudoaneurysm (TEE: n=2; CT: n=3); isthmic coarctation (TEE and CT: n=1). Regarding the presence or absence of these abnormalities, which are within the diagnostic domain of both imaging techniques, the results were fully concordant in 245 studies, and discordant in 7, with an overall agreement of 97%. In addition, some abnormal findings could be detected by TEE only: aortic insufficiency (n=36); intimal tear (n=25); spontaneous echocontrast effect in the false lumen (n=39 evaluations). Other abnormal findings could be detected by CT only: a pleural effusion in 4, a truncus anonymous dissection in 1, a pseudoaneurysm due to suture dehiscence of the distal anastomosis of the ascending aorta in 1 evaluation (which yielded ambiguous results by TEE, with turbulent flow departing from the graft). Conclusion. Both CT and TEE are atraumatic, safe and accurate techniques for serial follow-up imaging of patients treated for aortic dissection. Information provided by CT is largely redundant, rather than additive, to that provided by TEE. The latter should be probably preferred for shorter imaging time, accuracy and convenience, although CT might still play a role in selected cases of ambiguous TEE results.     

Transoesophageal echocardiography should be considered in patients with ischaemic stroke or transient ischaemic attack

BACKGROUND AND PURPOSE: In this present study, we tried to find out if there is a subgroup of patients that should not undergo transoesophageal echocardiography (TEE) after an ischaemic stroke or transient ischaemic attack (TIA). METHODS: A total of 441 consecutive unselected patients with ischaemic stroke or TIA suitable for anticoagulation were examined with TEE in the acute phase. The patients were divided into five subcategories according to their rhythm, age and the findings in carotid sonography, and into two groups according to the presence of clinical risk factors for ischaemic stroke or TIA. RESULTS: From the 441 studied patients, 60 (14%) had chronic or paroxysmal atrial fibrillation (AF) and 381 (86%) were in sinus rhythm (SR). Of the patients in SR, 46 (12%) were below 50 years old. The carotid sonography was conducted in 240 patients above 50 years old and in SR, and <50% internal carotid artery (ICA) stenosis was found in 194 (81%) patients and > or =50% ICA in 46 (19%) patients. Potential cardiac sources of embolism were found in patients both with AF or in SR (70% versus 46%), both below and above 50-year-old patients in SR (37% versus 47%), both in over 50-year-old patients in SR with <50% ICA stenosis and > or =50% ICA stenosis (41% versus 61%) and in patients in SR either without or with clinical risk factors for ischaemic stroke or TIA (43% versus 51%). On the basis of the TEE study, oral anticoagulation was started in 36 (9%) patients in SR. CONCLUSION: These results support TEE in patients with ischaemic stroke or TIA who are candidates for receiving oral anticoagulation.     

11例颈部动脉夹层致缺血性脑卒中支架治疗的护理

通过对12例颈部动脉夹层致缺血性脑卒中患者进行支架置入治疗,并对患者行术前、术后护理及术中配合。11例患者支架成功置入,术中、术后无并发症发生,1例患者由于血管因素未能完成。     

Brain atrophy evaluated by computed tomography in independent and institutionalized hip fracture patients

Purpose: To examine if there is an association between brain computed tomography (CT) findings and place of residence in a series of hip fracture patients.

Method: The CT scans taken immediately after hip fracture of 215 patients (mean age 81.6 years) living in their own homes or otherwise independently (home-dwelling group) and 95 patients (mean age 82.5 years) permanently institutionalized (institutionalized group) were analysed.

Results: The institutionalized patients had significantly more cortical cerebral (frontal, p?=?0.004; temporal, p?=?0.007; parietal, p?<?0.001) and central cerebral (third ventricle width, p?<?0.001; frontal horn width, p?<?0.001; midbody width, p?<?0.001) atrophy than the home-dwelling ones. This was also true of atrophy in the white-matter (WM) area (p?<?0.001). The institutionalized patients also had more atrophy of the cerebellar hemisphere (atrophy of the cerebellopontine angle cistern, p?=?0.002, greater fourth ventricle width, p?=?0.020). No significant difference was seen in the incidence of brain infarcts.

Conclusions: Hip fracture patients living in institutions have more brain atrophy than those living independently. The brain atrophy may be one factor in the multiple mechanism underlying their institutional admission.     

螺旋CT扫描下颈椎为下颈椎椎弓根螺钉的置入提供依据

目的通过测量颈椎椎弓根尺寸和进钉点进钉角度,为置入椎钉提供依据。方法选择2004年12月至2005年10月我院和惠州市中心人民医院骨科收治的怀疑颈椎损伤患者60例,其中男30例,平均年龄（43±19）岁,女30例,平均年龄（42±15）岁。均排除颈椎病理改变。60例患者行颈椎CT扫描,扫描范围第2颈椎～第1胸椎,扫描电压140kV,200—250mA。结果颈椎椎弓根平均内径为1．3—3．3mm,颈椎椎弓根平均外径为4．0～7．0mm,最小的椎弓根宽度在女性第3颈椎椎体,最小的椎弓根外径为3．2mm,最大椎弓根宽是第7颈椎,男性为11．1mm,女性为6．6mm。平均内壁皮质骨厚度为1．5—1．9mm,平均椎弓根轴长度29．3～33．7mm,平均椎弓根长轴与中线的夹角40．6°－49．6°,颈椎椎弓根钉进钉点到中线的垂直距离平均为20．2～23．7mm。结论颈椎椎弓根螺钉的置入应行CT测量,螺钉角度接近50°,进钉角度尽可能偏外侧。     

Patterns of myocardial perfusion in humans evaluated with contrast-enhanced 320 multidetector computed tomography

Left ventricular (LV) myocardial contrast enhancement can be recorded using 320 multi detector computed tomography (MDCT). We aimed to (1) assess patterns of regional myocardial perfusion at rest and compare them with NH(3) positron emission tomography (PET) (2) and to assess the effect of intravenous adenosine infusion on regional myocardial perfusion. To evaluate myocardial perfusion patterns at rest, we scanned 14 healthy subjects with PET and 14 age and gender matched subjects with 320 MDCT. To evaluate the effect of adenosine stress on relative perfusion patterns 14 subjects with near-normal epicardial coronary arteries were studied at rest and during adenosine stress. Relative perfusion was assessed as attenuation density (AD) in 16 segments of the LV, and each segment was divided into 3 layers: endo-, mid- and epi-cardial. During rest the relative AD by MDCT was lower in the lateral wall compared with the remainder of the LV (P?相似文献   

主动脉壁内血肿——一种不典型夹层的电子束CT诊断

目的:探讨主动脉壁内血肿(IMH)的电子束CT(EBCT)影像特征及对临床诊治的指导意义。方法:13例经EBCT连续容积增强扫描的主动脉IMH患者,综合分析其EBCT影像特征及临床特点。结果:EBCT所见IMH的直接征象:13例主动脉壁新月形或环形低密度增厚,无内膜片及真、假腔。7例血肿外缘轻度环状强化。血肿CT值60~108Hu。间接征象:穿透性溃疡征9例,钙化内移3例,主动脉壁粥样硬化8例,一侧或双侧胸腔积液7例(2例分别合并叶间裂或心包积液)。并发征象:动脉瘤2例,B型主动脉夹层1例。结论:EBCT是检出主动脉IMH的快速、无创检查方法,可清晰显示IMH的直接、间接征象及并发征象,对临床的诊治有重要的指导意义。     

Painless aortic dissection masquerading as brainstem stroke with catastrophic anticoagulant use

Painless aortic dissection with only focal neurological symptoms and signs can be a great challenge to the emergency physician. Inadvertently and erroneous treatment of stroke may threaten patient's life. We present a patient with painless aortic dissection (DeBakey I), which was initially misdiagnosed as brainstem stroke with catastrophic anticoagulant use. Finally, the patient died of multiorgan failure after surgical intervention.     

Arrhythmogenic right ventricular cardiomyopathy with left ventricular involvement and aortic dissection

Ten years ago, a 59-year-old patient presented with ventricular fibrillations. The resting ECG showed findings typical for ARVC. Echocardiography and ventriculography confirmed the diagnosis of ARVC showing a dilated right ventricle with aneurysms. MRI showed additional fatty replacement of the LV. Furthermore, the diagnosis of a chronic aortic dissection was established. Two years after ICD implantation, the patient died of progressive right heart failure. On autopsy, most of the RV and parts of the LV were replaced by fatty tissue, and the media of the aorta showed degenerative changes. A pathogenetic link between the two diseases remains speculative at this time.     

多排螺旋CT及数字减影血管造影对B型主动脉夹层评估的意义

目的探讨多排螺旋CT血管造影(CTA)和数字减影血管造影(DSA)诊断主动脉夹层(AD)的一致性及对主动脉夹层腔内修复术(TEVAR)的指导意义。方法回顾性分析资料完善的40例AD患者,比较两种方法显示的AD破口数、破口与左锁骨下动脉(LSA)的距离、左锁骨下动脉远端胸主动脉直径、主动脉夹层累及的范围及主动脉主要分支血管的累及情况、真假腔内血栓形成及钙化状况、行覆膜支架后内漏的发生率。结果两种检查方法在检测AD破口数、破口距LSA的距离、胸主动脉直径方面差异无统计学意义。CTA、DSA发现夹层累及左、右侧髂动脉平面的例数分别为16例(40.0%)、6例(15.0%)和15例(37.5%)、6例(15.0%),两种方法在检测夹层累及左、右侧髂动脉平面时的准确度差异均有统计学意义(P<0.05)。CTA可检测出夹层血栓、动脉壁钙化,而DSA无法显示。40例AD患者行TEVAR 34例,覆膜支架置入后DSA即刻检测发现内漏者11例(32.4%)。结论 CTA、DSA两者对诊断AD有较好的一致性,对TEVAR术前、后有指导价值。