主动脉壁内血肿的64层螺旋CT诊断价值

目的：评价64层螺旋CT对主动脉壁内血肿的价值及优势。方法：采用64层螺旋CT,连续容积增强扫描,对32例主诉急性胸背痛患者行CT检查并诊断为壁内血肿。结果：32例按Stanford分型：A型8例,B型24例。其直接征象：沿主动脉壁的环形或新月形低密度影,无撕裂的内膜片。间接征象：钙化的动脉壁内移10例,溃疡18例,主动脉粥样硬化改变8例。并发胸腔积液3例。结论：螺旋CT血管成像技术可以在无创或微创的情况下清晰地显示壁内血肿,为临床诊断和治疗提供有价值的依据。     

多层螺旋CT血管成像在主动脉壁间血肿的临床应用

目的探讨主动脉壁间血肿（IMH）MSCT表现和诊断价值。方法10例经多层螺旋CT诊断及临床证实的IMH,男6例,女4例。使用16层螺旋CT检查,应用多平面重建、最大密度投影和容积成像等后处理方法显示壁间血肿及穿透性溃疡。结果10例IMH中,A型2例,B型8例,其中2例局限于胸主动脉,6例累及胸腹主动脉（止于肾动脉上方2例,髂总动脉分叉上方2例,2例累及双侧髂总动脉）。MSCT表现为主动脉腔内新月形或环形充盈缺损,内壁较光整,钙化内膜片内移及局灶性尖角样穿透溃疡形成,主动脉腔内无明确内膜片显示。结论多层螺旋CT能为主动脉壁间血肿的诊断、鉴别诊断和治疗提供准确的信息。     

主动脉壁内血肿的影像学诊断及鉴别诊断

目的：探讨主动脉壁内血肿的影像学诊断和鉴别诊断。方法：回顾性分析16例经临床及CT和MRI诊断的主动脉壁内血肿及5例可疑壁内血肿患者的病例资料。12例因胸痛或腹痛入院、经CT或MRI扫描时发现,4例为外伤或内科疾病行胸部或腹部检查时意外发现;另外搜集18例主动脉夹层及11例主动脉瘤患者的影像学资料。结果：16例主动脉壁内血肿,表现为主动脉壁环形增厚7例,新月形增厚5例,环形和新月形增厚同时存在或不规则增厚4例,腔内无内膜片及真假两腔形成,增厚的血管壁内无对比剂进入。5例可疑主动脉壁内血肿表现为管壁轻度环形增厚。18例主动脉夹层均可见真假两腔及内膜片,其中14例其真假腔在横轴面图像上表现为＂D＂字形或反＂D＂字形,真假两腔内均有对比剂进入;11例主动脉瘤表现为血管瘤样扩张或梭形扩张,无真假两腔和内膜片,其中8例可见附壁血栓。结论：CT平扫及增强扫描结合图像后处理技术及MRI多方位成像能够诊断较为典型的主动脉壁内血肿,并与主动脉其它常见疾病相鉴别。     

Acute spontaneous aortic pathologies associated with intramural hematoma: can a differential diagnosis be made by imaging techniques?

Acute intramural aortic hematoma may result from ruptured vasa vasorum without intimal disruption (IMH hereafter) but can also be found in association with processes in which an intimal lesion is present, such as aortic dissections (AD), where the hematoma represents the acute thrombosis of the false lumen, or in penetrating atherosclerotic ulcers (PAU), where blood collects beyond the disrupted internal elastic lamina. As the clinical presentation of these conditions is very similar, imaging techniques should aim both to diagnose the hematoma and to characterize the underlying pathology. This review critically analyzes the diagnostic potential of several imaging methods based on personal experience and literature reports. Although intramural hematoma can be easily diagnosed unrespective of the tomographic imaging modality, it is usually difficult to distinguish between IMH and hematomas associated either to AD or to PAU. Indeed, only PAU related hematomas can be consistently diagnosed due to the high probability of unveiling the causative wall ulceration; conversely, the differential diagnosis between IMH and AD - associated hematomas is still matter of controversy. According to the literature, the two conditions cannot be differentiated by transesophageal echocardiography, though some reports state that a distinction might be made by MR imaging. As regards CT, only a small percentage of AD - associated hematomas exhibit clear evidence of a typical intimal flap, allowing for a safe diagnosis to be made: often, unfortunately, the intimal lesion subsequently found at surgery cannot be detected, yielding a picture of IMH. Therefore, the radiological report should give the same diagnostic probability to both conditions.     

MR imaging of intracranial carotid occlusion

The MR scans of seven patients with intracranial carotid occlusion (five proved, two presumed) were reviewed to evaluate the MR signal characteristics seen in this disorder. Five patients had clinical signs of cerebral infarction. Of the remaining two patients, one was asymptomatic and the other had a long-standing occlusion and headaches. We correlated the MR findings with cerebral angiography in five patients and with CT scans in six patients. All occluded vessels demonstrated MR signal predominantly isointense to brain on proton-density- T1- and T2-weighted images. Since there is an absence of flow, the MR signal is based on the intrinsic properties of the arterial thrombus and possibly on the chronicity of the occlusion. The pathogenesis and histopathology of intravascular thrombus differ significantly from extravascular hematoma, which accounts for the differences in their MR signal characteristics. The demonstration of occluded intracranial vessels may solidify the diagnosis of stroke in cases in which clinical and/or CT findings are equivocal. In patients presenting with infarction, an occluded carotid artery by MR may obviate the need for angiography; however, the demonstration of a patent carotid in conjunction with infarction suggests the possibility of an embolus, which may require angiography. We believe that MR is a valuable adjunct to CT in evaluating patients with cerebrovascular infarction.     

Endovascular repair of thoracic aortic aneurysm and intramural hematoma in giant cell arteritis

An 80-year-old woman with established giant cell arteritis presented at the authors' institution with a 6.5-cm false aneurysm of the descending thoracic aorta complicated by focal dissection and intramural hematoma after a 1-week history of acute-onset chest pain. The patient underwent uncomplicated endovascular aortic repair with a 32-mm x 15-cm TagExcluder stent-graft. After the procedure, the intramural hematoma resolved and the patient's corticosteroid and immunosuppressive therapy was repeatedly adjusted. However, the giant cell arteritis activity relapsed after 8 months with development of a similar 1.5-cm false aneurysm below the thoracic stent-graft, complicated by focal intramural hematoma. Repeat uncomplicated thoracic stent-graft implantation was performed and CT follow-up displayed resorption of the intramural hematomas with no evidence of endoleak or any new aortic pathology. This report discusses the difficult management of patients with relapsing active aortic giant cell arteritis and the potential role for endovascular thoracic aortic repair.     

Aortic intramural hematoma: aspects with spiral computerized tomography

PURPOSE: To evaluate the signs of aortic intramural hematoma with helical CT and the diagnostic role of this technique in patients with this condition. MATERIAL AND METHODS: We reviewed the CT findings of 396 patients submitted to emergency examinations for suspected aortic dissection from 1995 to 1999. Only 18 patients (6 women and 12 men) had CT signs of aortic intramural hematoma. Helical CT studies were carried out with the following parameters: slice thickness 10 mm, reconstruction index 10, feed 1.5 mm, conventional algorithm with minimum values of 130 kV and 125 mA. All patients were examined with dynamic contrast-enhanced CT, before and after a power injection of 130 mL ionic contrast material. We studied: hematoma localization and longitudinal extension; thickness and density of aortic wall; presence and location of intimal calcifications; integrity of intimal wall; hemomediastinum and/or hemothorax. RESULTS: Aortic wall thickening appeared as a high density crescent-shaped area at baseline CT and had low density on enhanced images in all patients. Thickening was eccentric in 14/18 patients and concentric in 4/18 only; it always exceeded 4 mm. We found some intimal calcifications in 8 patients and hemothorax and/or hemomediastinum in 9 patients. A patient with type A hematoma died of cardiac tamponade a few hours after CT diagnosis. Six patients (5 type B and 1 type A) underwent anti-hypertensive treatment and radiological follow-up. Eleven patients (6 type A and 5 type B) underwent prosthesis replacement and 5 of them (3 type A and 2 type B) died of postoperative complications. In the 5 type B patients surgery was performed because of treatment-resistant pain and of the onset of ischemic complications to abdominal organs caused by involvement of the main collateral branches of the aorta. One patient with type A hematoma was submitted to drug treatment because it was judged unresectable. DISCUSSION AND CONCLUSIONS: Intramural hematoma of the aorta is a distinct pathological entity, which should not be confused with aortic dissection. The imaging techniques (TEE, CT, MRI) have an important role in the final diagnosis of aortic hematoma. Presently Helical CT and MR angiography are the main tools in the early diagnosis of this condition before the development of complications. In our experience helical CT, before and after the administration of contrast material, was accurate in identifying the hematoma localization and extension.     

MRI和螺旋CT对主动脉夹层的对比研究及其临床应用

目的对比分析磁共振成像(MR I)和螺旋CT诊断主动脉夹层(AD)的影像特征,评价2种技术对临床的应用价值。方法回顾性分析经手术或临床证实的18例AD的MR I和螺旋CT表现。结果2种先进检查技术诊断AD的敏感性和特异性均较高,能不同程度地显示AD的范围及其分型、真假腔、内膜片和内膜破口、附壁血栓和壁内血肿、主动脉的扩张和狭窄及其分支血管受累情况。结论对疑有AD者应行MR I或螺旋CT检查,MR I与CT对病变范围及分型、真假腔及主动脉的狭窄和扩张的显示相似;而内膜片、内膜破口、附壁血栓和壁内血肿、主动脉整体及分支受累的显示MR I明显优于螺旋CT;对内膜及主动脉壁钙化、急危重者的检查螺旋CT优于MR I。     

Penetrating atherosclerotic ulcers of the descending thoracic aorta: evaluation with CT and distinction from aortic dissection.

Penetrating atherosclerotic ulceration of the aorta is a poorly understood entity that clinically mimics classic aortic dissection but has imaging features that are distinctly different. In a review of 16 patients with penetrating atherosclerotic ulceration, patients were typically hypertensive (n = 14), and they experienced chest or back pain (n = 13). All patients had an abnormal chest radiograph, with diffuse (n = 14) or focal (n = 2) enlargement of the descending thoracic aorta. Features at contrast material-enhanced computed tomography (CT) included intramural hematoma (n = 16), focal ulcer (n = 15), displaced intimal calcification (n = 13), pleural and/or extrapleural fluid (n = 7), mediastinal fluid (n = 4), and a thick or enhancing aortic wall (n = 6). The chest radiograph and CT findings were compared in patients treated conservatively (n = 9) and surgically (n = 7). These findings did not correlate with the need for surgery. Eight of nine conservatively treated patients were asymptomatic after treatment with antihypertensive medication. Contiguous dynamic contrast-enhanced CT of the aorta enables distinction of ulceration from dissection, which is particularly important in the hemodynamically unstable patient because the surgical management of ulceration is more extensive than that for aortic dissection.     

Ulcerlike lesions of the aorta: imaging features and natural history

PURPOSE: To document the natural history of ulcerlike aortic lesions and determine whether any computed tomographic (CT) features predict outcome. MATERIALS AND METHODS: CT scans from 1994 to 1998 that depicted an ulcerlike aortic lesion were retrospectively evaluated. Features evaluated included lesion and aortic size and intramural hematoma. Initial CT findings were correlated with clinical data and subsequent CT findings. RESULTS: There were 56 lesions in 38 patients. Follow-up (mean, 18.4 months) CT scans were available for 33 lesions. Stability of the lesion and adjacent aorta was noted in 21 lesions. Two lesions were unchanged, although associated intramural hematoma regressed over 1-2 months. Ten lesions showed mild to moderate increase in aortic diameter (mean follow-up, 19.8 months) either with (seven lesions) or without (one lesion) increase in size of the lesion or with incorporation of the lesion into the aortic wall contour (two lesions). Of all 56 lesions, 37 were clinically stable, two were associated with recurrent chest and/or back pain, eight underwent surgical resection or stent placement, and two were in patients who died. Seven lesions were in patients lost to follow-up. No initial CT feature was predictive of CT outcome, although lack of pleural effusion correlated with clinical stability. CONCLUSION: Most ulcerlike aortic lesions are asymptomatic and do not enlarge. About one-third of lesions progress, generally resulting in mild interval aortic enlargement.     

Helical CT: a useful technique in the evaluation of aortic intramural hematoma

Purpose: To investigate the diagnostic role of helical CT in aortic intramural hematoma. Material and methods: We retrospectively evaluated CT images obtained during a 6-year period, between 1994 and 2000, in 427 patients who underwent helical CT. Only 21 patients had typical findings of aortic intramural hematoma. All studies were performed with helical technique before and after a power injection of nonionic contrast material. Results: Twenty-one patients had aortic wall thickening (9 type A and 12 type B in Stanford's classification). Wall thickening was more than 4 mm in all cases, it was irregular in shape in 16/21 patients (76 %) and had a regular concentric shape in the remaining 5/21 patients (24 %). One patient with type A hematoma died soon after CT diagnosis because of arrhythmia caused by hemopericardium. Five patients (4 type B and one type A) underwent pharmacological therapy and radiological follow-up. Fifteen patients (7 type A and 8 type B) underwent prosthetic surgery and six of these died of postoperative complications. Conclusion: Helical CT represents the first step in the early diagnosis of aortic intramural hematoma before complications develop. In our experience, which agrees with the reports of other authors, helical CT is an accurate and valuable investigation for identifying the location and extent of an aortic intramural hematoma.     

1.5-T MR imaging of pituitary microadenomas: technical considerations and CT correlation

Thirty-seven patients with suspected pituitary tumors were evaluated prospectively with MR imaging at 1.5 T. MR detected a microadenoma at its correct location in all eight patients who underwent transsphenoidal surgery, while CT showed a focal abnormality in the correct location in only four of the eight patients. In patients who were clinically and endocrinologically considered to harbor a microadenoma, MR detected a focal pituitary signal abnormality in 83% and CT demonstrated a focal density abnormality in 42%. Infundibular displacement, focal gland convexity, and sellar-floor abnormality were seen equally well with CT and MR. MR imaging protocol included sagittal T1-weighted spin-echo, coronal inversion-recovery, and coronal spin-echo or cardiac-gated spin-echo images. Although inversion-recovery images were superior in detecting focal pituitary lesions, some microadenomas were better seen on T2-weighted images. Cardiac-gated spin-echo images showed focal pituitary lesions better than ungated images did. Our technique demonstrates MR's superior sensitivity to CT in detecting a pituitary microadenoma.     

128层螺旋CT血管成像在主动脉粥样硬化性溃疡中的应用

目的：通过128层螺旋CT血管成像探讨主动脉粥样硬化性溃疡的影像学特点,提高对该病的认识及诊断水平。方法：回顾性分析52例128层螺旋CT血管成像诊断的主动脉粥样硬化性溃疡,均经介入、手术或保守治疗证实,其中47例以急性主动脉综合征就诊,5例以胸闷、其他部位不适或体检就诊。观察溃疡的部位、形态、大小、深度、数量及周围结构关系。结果：52例患者中单发溃疡48例,多发溃疡4例。52例患者中并发主动脉壁内血肿35例,并发假性动脉瘤2例,并发主动脉夹层2例;30例伴有心包积液或（和）胸腔积液,其中2例为中等量血性胸腔积液。结论：128层螺旋CT血管成像能够对主动脉粥样硬化性溃疡作出准确诊断,可作为该病的首选检查方法。     

主动脉壁内血肿的多层面螺旋CT诊断

目的:评价多层面螺旋CT诊断主动脉壁内血肿的价值.材料和方法:对23例怀疑主动脉病变的患者进行多层面螺旋CT扫描并诊断为主动脉壁内血肿.两名有经验的心血管放射医师按照CT标准做出诊断.使用16排多层面螺旋CT获得1.25mm层厚(1mm重建间隔)图像,应用多平面重建、曲面重建、最大密度投影和容积重建等方法显示壁内血肿及穿透溃疡.结果:23例主动脉壁内血肿中,1例A型,22例B型;B型壁内血肿中,仅累及降主动脉的8例,胸腹主动脉受累11例,局限于腹主动脉3例;11壁内血肿伴主动脉穿透溃疡,其中2例行带膜内支架治疗.结论:多层面螺旋CT能为主动脉壁内血肿的诊断、鉴别诊断和治疗提供重要信息.     

Aortic intramural hematoma: Review of high-risk imaging features

Aortic intramural hematoma is among the spectrum of pathologies that comprises acute aortic syndrome and carries a risk of progression to aortic dissection, aneurysm, rupture, and other complications. Evaluation by CT can identify imaging features associated with higher risk of complications. Ulcer-like projections, enlarged aortic diameter, increased hematoma thickness, and Stanford type A classification are associated with progression to complications. The significance of intramural blood pools within the hematoma and associated pleural/pericardial effusions is less certain. Detailed evaluation of intramural hematoma with CT can provide critical prognostic information with implications for patient management.     

主动脉壁内血肿的64层螺旋CT诊断

目的：探讨64层螺旋CT诊断主动脉壁内血肿（AIH）的价值。方法：对25例主诉急性胸背痛患者进行64层螺旋CT检查（连续容积扫描）,均经临床及影像学检查诊断为主动脉壁内血肿。结果：25例AIH患者按Stanford分型,A型2例,B型23例。MSCT征象：25例均见主动脉壁呈新月形或环形增厚,厚度≥5mm,无内膜破裂形成的双腔主动脉征象。平扫呈高密度11例,高密度为主的混杂密度8例,等密度6例。21例见钙化内移征象,5例可见穿透性溃疡征,动脉粥样硬化性改变18例,内膜渗透3例,血肿分层征象2例。并发心包积液4例,胸腔积液16例,主动脉夹层3例,主动脉瘤2例。结论：MSCT能为主动脉壁内血肿的诊断和治疗提供重要信息,且便于治疗后随访观察,可以作为AIH的首选诊断及随访检查方法。     

Predictive value of small ulcers in the evolution of acute type B intramural hematoma

Objective

To assess the long-term evolution and predictive factors of type B intramural hematoma (IMH).

Material and methods

34 patients (33 men), mean age: 67 years (47–87) diagnosed with type B IMH by computed tomography (CT) and followed up clinically and by CT yearly. Mean follow-up was 5.9 years (2–13 years). Two evolution patterns were considered: (a) regression and (b) progression. Clinical and imaging variables were analyzed for assessing their predictor values.

Results

Evolution at one year was to regression in 56% and to progression in 44% of cases. There were no association among age, sex, other aortic abnormalities, presence of atherosclerotic disease or blood pressure, initial maximum aortic diameter, indexed maximum aortic diameter, IMH thickness or length, presence or absence of mediastinal hematoma and the evolution of type B IMH. Ten patients had small aortic ulcers in the acute phase. The presence of ulcers was related with progression of IMH. No differences were observed in evolution between the control at first year and the last control.

Conclusions

The presence of small ulcers is a strong predictor of evolution in acute type B IMH. In addition, the regression group remains completely stable after the first year of evolution.     

Vascular diseases of the thorax: evaluation with multidetector CT

The list of vascular diseases in the thorax has been narrowed to three, which are considered essential information for radiologists interpreting CT scans of the thorax: (1) aortic dissection and its variants, intramural hematoma and penetrating atherosclerotic ulcer; (2) acute pulmonary embolism; and (3) coronary artery disease. The spatial resolution of multidetector CT is such that CT has become the imaging modality of choice for aortic dissection and pulmonary embolism. This move away from angiography has transpired over the last decade; perhaps the next decade will see the same occur for evaluation of coronary artery disease.     

颅内静脉窦血栓形成的早期MRI诊断及病理基础

目的:研究颅内静脉窦血栓形成(CVST)的MR表现及其病理基础,旨在提高早期诊断水平.方法:回顾分析经临床和影像学方法确诊的11例CVST患者.MR检查技术包括平扫、增强扫描及MRV;其中4例行CT平扫检查;3例行DSA检查.结果:11例CVST累及上矢状窦5例,横窦1例,乙状窦1例,直窦1例,上矢状窦及横窦及乙状窦联合受累2例,横窦及乙状窦联合受累1例.CVST的直接征象:急性期血栓3例,T1 WI呈等信号或等高混杂信号,T2 WI呈低信号,周围可见稍高信号的环,为增厚的硬膜;亚急性期血栓8例,T1 WI及T2 WI均以高信号为主.增强扫描受累静脉窦可见空"三角"征或"充盈缺损"征.MRV可显示受累静脉窦不显影或者充盈缺损形成.CVST的继发脑损害包括脑肿胀、出血及梗死等.结论:磁共振检查对CVST的早期诊断具有重要价值.对于T2 WI呈低信号的急性期血栓,应仔细观察围是否有较高信号的环形改变,进一步行增强扫描结合MRV检查可作出早期准确的诊断.     

Useful CT findings for predicting the progression of aortic intramural hematoma to overt aortic dissection

PURPOSE: The purpose of this work was to assess useful CT findings for predicting the progression of aortic intramural hematoma to aortic dissection. METHOD: We analyzed the CT findings of 29 patients with aortic intramural hematoma with regard to the following: involved site, maximum thickness of hematoma, presence or absence of compression of true lumen, and pericardial and pleural effusion. CT findings were compared with those of the patients who progressed to aortic dissection (Group I) and those who did not (Group II). Each CT finding was evaluated with independent t test and Mann-Whitney U test (p < 0.05). RESULTS: Seven of 8 cases of Type A aortic intramural hematoma and 3 of 21 cases of Type B aortic intramural hematoma progressed to aortic dissection. The type of aortic intramural hematoma, maximum thickness of hematoma, compression of true lumen, and pericardial or pleural effusion were significantly different in Groups I and II. CONCLUSION: Type A aortic intramural hematoma, maximum thickness of hematoma, compression of true lumen, and pericardial or pleural effusion are the useful CT findings for predicting the progression of aortic intramural hematoma to aortic dissection.