脑血管CTA预测高血压脑出血患者血肿扩大的临床分析

 目的 分析脑血管CTA检查中造影剂外渗与急性期高血压脑出血血肿扩大的关系。 方法 63例急性期高血压脑出血患者入院后行头颅CT及脑血管CTA检查,24 h后复查头颅CT,观察造影剂外渗情况,分析脑 血管CTA检查过程中造影剂外渗与血肿扩大的关系。 结果 血肿扩大组11例(17.46%),血肿无扩大组52例 (82.54%)。血肿扩大11例患者中造影剂外渗者9例,CTA阳性预测血肿扩大准确率81.82%,造影剂外渗患者血肿量增加（27.63 ±11.52）ml,造影剂无外渗患者血肿量增加（3.12±1.48）ml（ P =0.006）,血肿扩大组血肿量增加（20.18±12.27） ml,血肿无扩大组出血量增加（1.59±1.05） ml（ P =0.027）。 结论 在脑血管CTA检查中,造影剂外 渗与急性期高血压脑出血血肿扩大有明显相关性,可预测高血压脑出血血肿扩大情况。     

Extravasation of intracranial aneurysm during computed tomography angiography: mimicking a blood vessel

Two cases of contrast media extravasation of a ruptured aneurysm during computed tomography angiography (CTA) are described. The contrast media extravasation appeared as a highly attenuated twisted ribbon-like structure originating from the aneurysmal dome, and this mimicked a vascular structure. Because rebleeding of an aneurysm is accompanied by disastrous consequences, it is important to understand the imaging feature of active bleeding on CTA.     

Improved diagnosis of actively bleeding aneurysm on CT angiography using delayed CT images

Computed tomographic angiography (CTA) is being increasingly utilized in the non-invasive diagnosis of aneurysmal subarachnoid hemorrhage (SAH). There are emerging reports of diagnosis of active aneurysmal bleeding on CTA, furthering our understanding of imaging features of active extravasation on cross-sectional studies. We demonstrate imaging characteristics of two such cases of active contrast extravasation from intracranial aneurysms. Additionally, we demonstrate that delayed CT images greatly improve the confidence of this diagnosis by demonstrating pooling of contrast in the subarachnoid space. Prompt recognition and management can improve prognosis of this potentially lethal condition.     

Extravasation on three-dimensional CT angiography in patients with acute subarachnoid hemorrhage and ruptured aneurysm

Three-dimensional computed tomographic angiography (CTA) is a noninvasive technique for detecting lesions after acute subarachnoid hemorrhage. We encountered extravasation on CTA, a finding that has not been reported previously. Three patients with saccular aneurysms showed extravasation on CTA performed within 3 h of the onset of hemorrhage, and all three patients died within 2 weeks. At autopsy, the site of rupture of the aneurysm was confirmed in all three cases. There were two patterns of extravasation shown by CTA, which seemed to depend on the direction of rupture. Extravasation on CTA might represent the natural progression of ruptured aneurysm and may indicate a poor prognosis.     

Contrast extravasation on CT predicts mortality in primary intracerebral hemorrhage

BACKGROUND AND PURPOSE: Recent studies of intracerebral hemorrhage (ICH) treatments have highlighted the need to identify reliable predictors of hematoma expansion. The goal of this study was to determine whether contrast extravasation on multisection CT angiography (CTA) and/or contrast-enhanced CT (CECT) of the brain is associated with hematoma expansion and increased mortality in patients with primary ICH.MATERIALS AND METHODS: All patients with primary ICH who underwent CTA and CECT, as well as follow-up noncontrast CT (NCCT) before discharge/death from January 1, 2003, to September 30, 2005, were retrospectively identified. One neuroradiologist reviewed admission and follow-up NCCT for hematoma size and growth. A second neuroradiologist independently reviewed CTA and CECT for active contrast extravasation. Univariate and multivariate logistic regression analyses were performed to evaluate the significance of clinical and radiologic variables in predicting 30-day mortality, designated as the primary outcome. Hematoma growth was considered as a secondary outcome.RESULTS: Of 56 patients, contrast extravasation was seen in 17.9% of patients on initial CTA and in 23.2% of patients on initial CECT following CTA. Univariate analysis showed that the presence of extravasation on CT, large initial hematoma size (>30 mL), the presence of “swirl sign” on NCCT, the Glasgow Coma Scale and ICH scores, and international normalized ratio were associated with increased mortality. On multivariate analysis, only contrast extravasation on CT (P = .017) independently predicted mortality. Contrast extravasation on CT (P < .001) was also an independent predictor of hematoma growth on multivariate analysis.CONCLUSION: Active contrast extravasation on CT in patients with primary ICH independently predicts mortality and hematoma growth.

Primary intracerebral hemorrhage (ICH) is one of the most devastating forms of stroke, with 30-day mortality rates ranging from 35% to 44%.^1–3 Recent studies of hemostatic treatments such as recombinant activated factor VII as a means to reduce hematoma growth and impact clinical outcome in patients with primary ICH have highlighted the need to identify reliable predictors of hematoma expansion.^4–6 A number of clinical and radiologic variables have been associated with poor outcome following ICH, including age; blood glucose level; Glasgow Coma Scale (GCS) score; and hemorrhage location, size, and intraventricular extension.^7–12 Several prognostic models for ICH have been developed incorporating both clinical and radiologic variables, among them the ICH score, which includes the GCS score, advanced age, hematoma location, ICH volume, and the presence of intraventricular hemorrhage, to predict 30-day mortality.¹³Nearly all studies of prognostic variables with respect to imaging have focused exclusively on noncontrast CT (NCCT). One study by Becker et al from 1999¹⁴ examined the role of iodinated contrast administration in primary ICH, concluding that contrast extravasation was independently associated with increased mortality. However, CT technology has evolved considerably since 1999, primarily due to the introduction of multisection CT scanners. High-quality CT angiography (CTA) and contrast-enhanced CT (CECT) studies of the brain are now routinely performed following contrast administration. The respective roles of CTA and CECT were not separately defined in Becker''s study, in which single-section CT scanner technology was used.¹⁴ A recent study by Goldstein et al¹⁵ demonstrated an independent association between contrast extravasation and hematoma expansion but did not explore the relationship with mortality.The goal of this study was to determine whether contrast extravasation as visualized on multisection CTA and/or CECT is associated with hematoma expansion and increased mortality in patients with primary ICH.     

脑出血患者早期造影剂外渗率的临床意义简

目的：脑出血患者CT造影外渗率可提示血肿扩大,本研究评价脑灌注CT（PCT）推导表面渗透性（PS）是否可检测早期CT造影剂外渗率差异及其意义。方法20例脑出血患者入院时及入院24 h后进行CT检查,入院时进行PCT-PS扫描。采用Wilcoxon秩和检验比较下列兴趣区的PS值：①斑点征病灶;②造影剂渗漏（PCCT-L）病灶;③排除外渗的血肿;④外渗至对侧区域;⑤无外渗患者的血肿;⑥无外渗患者血肿的对侧面积。此外,比较24 h后的血肿扩展情况。结果上述6项参数的PS分别为（6．5±1．6）、（1．0±0．4）、（0．12±0．39）、（0．26±0．09）、（0．4±0．3）、（0．09±0．32）ml×min-1×（100 g）-1。斑点征病灶的PS值和PCCT-L病灶的PS与其他几项参数比较差异有统计学意义（P＜0．05）。外渗阳性患者的血肿体积由（34±41）ml增加至（40±46）ml,外渗阴性患者则由（20±32）ml降至（17±27）ml。结论与PCCT-L病灶和血肿比较,PCT-PS参数检测显示CTA斑点征病灶造影剂较高外渗率,早期外渗与血肿扩展相关。     

An investigation into current protocols and radiographer opinions on contrast extravasation in Irish CT departments

BackgroundIodinated contrast extravasation is a serious complication associated with intravenous administration in radiology. Departmental protocols and the radiographer's approach on both prevention techniques and treatment will affect the prevalence of extravasation, and the eventual outcome for the patient when it does occur.AimsTo examine contrast extravasation protocols in place in Irish CT departments for alignment with European Society of Urogenital Radiology (ESUR) Guidelines (2014); to establish radiographer's opinions on contrast extravasation; and to examine radiographer adherence to protocols.MethodsContrast extravasation protocols from a purposively selected sample of CT departments across Ireland (n = 6) were compared to ESUR guidelines, followed by an online survey of CT radiographers practicing in the participating centres.ResultsAll participating CT departments (n = 5) had written protocols in place. High risk patients, such as elderly or unconscious, were identified in most protocols, however, children were mentioned in just one protocol and obese patients were not specified in any. The response rate of CT radiographers was 23% (n = 24). 58% (n = 14) of respondents indicated that contrast extravasation was more likely during CTA examinations. While high levels of confidence in managing extravasation were reported, suggested treatment approaches, and confidence in same, was more variable. Clinical workload in CT departments was also identified as a factor impacting on patient care and management.ConclusionWhile contrast extravasation protocols were generally in line with ESUR Guidelines, high risk patients may not be getting sufficient attention. More radiographer awareness of patient monitoring needs, particularly in busy departments with a heavy workload may also reduce extravasation risk, and improve management of same.     

Negative spot sign in primary intracerebral hemorrhage: potential impact in reducing imaging

Intracerebral hemorrhage (ICH) is one of the most devastating and costly diagnoses in the USA. ICH is a common diagnosis, accounting for 10–15 % of all strokes and affecting 20 out of 100,000 people. The CT angiography (CTA) spot sign, or contrast extravasation into the hematoma, is a reliable predictor of hematoma expansion, clinical deterioration, and increased mortality. Multiple studies have demonstrated a high negative predictive value (NPV) for ICH expansion in patients without spot sign. Our aim is to determine the absolute NPV of the spot sign and clinical characteristics of patients who had ICH expansion despite the absence of a spot sign. This information may be helpful in the development of a cost effective imaging protocol of patients with ICH. During a 3-year period, 204 patients with a CTA with primary intracerebral hemorrhage were evaluated for subsequent hematoma expansion during their hospitalization. Patients with intraventricular hemorrhage were excluded. Clinical characteristics and antithrombotic treatment on admission were noted. The number of follow-up NCCT was recorded. Of the resulting 123 patients, 108 had a negative spot sign and 7 of those patients subsequently had significant hematoma expansion, 6 of which were on antithrombotic therapy. The NPV of the CTA spot sign was calculated at 0.93. In patients without antithrombotic therapy, the NPV was 0.98. In summary, the negative predictive value of the CTA spot sign for expansion of ICH, in the absence of antithrombotic therapy and intraventricular hemorrhage (IVH) on admission, is very high. These results have the potential to redirect follow-up imaging protocols and reduce cost.     

Inferior vena cava diameter on CT angiography predicts mesenteric angiography positive for extravasation in colonic diverticular bleeding

Purpose

Transcatheter arterial embolization (TAE) for colonic diverticular bleeding (CDB), an established procedure for hemostasis, is sometimes complicated by spontaneous hemostasis and unclear bleeding site on angiography despite active arterial bleeding on preoperative computed tomography angiography (CTA). Therefore, to investigate and increase the feasibility of TAE, this retrospective study evaluates the clinical and radiological features related to positive extravasation on angiography.

Material and methods

Sixty CDB patients with extravasation on CTA underwent TAE between January 2011 and February 2021 and were divided into extravasation-positive (P-group; n?=?25) and -negative groups (N-group; n?=?35) based on the superior or inferior mesenteric angiography. Patient characteristics, laboratory findings, the diameter of the inferior vena cava (IVCD), the diameter of superior and inferior mesenteric veins, and technical outcomes were evaluated.

Results

TAE was successful in 24 patients in the P-group (96%) and 14 in the N-group (40%) (p?<?0.001). Univariate analysis revealed “usage of anticoagulant” (p?<?0.05) and “larger IVCD (p?<?0.05) on preoperative CTA” to be significant predictors of positive extravasation. In the multivariate analysis, IVCD remained significant with an adjusted odds ratio of 1.17. The IVCD cutoff value was 13.6 mm (area under the curve?=?0.72, sensitivity?=?84.0%, specificity?=?54.3%). There were no significant differences in other parameters.

Conclusion

Measurement of IVCD in CDB with the cutoff value of 13.6 mm can be a simple and useful indicator to predict the detectability of extravasation following TAE procedures.

     

Fellows' Journal Club: Contrast Extravasation on CT Angiography Predicts Hematoma Expansion and Mortality in Acute Traumatic Subdural Hemorrhage

BACKGROUND AND PURPOSE:The presence of active contrast extravasation at CTA predicts hematoma expansion and in-hospital mortality in patients with nontraumatic intracerebral hemorrhage. This study aims to determine the frequency and predictive value of the contrast extravasation in patients with aSDH.MATERIALS AND METHODS:We retrospectively reviewed 157 consecutive patients who presented to our emergency department over a 9-year period with aSDH and underwent CTA at admission and a follow-up NCCT within 48 hours. Two experienced readers, blinded to clinical data, reviewed the CTAs to assess for the presence of contrast extravasation. Medical records were reviewed for baseline clinical characteristics and in-hospital mortality. aSDH maximum width in the axial plane was measured on both baseline and follow-up NCCTs, with hematoma expansion defined as >20% increase from baseline.RESULTS:Active contrast extravasation was identified in 30 of 199 discrete aSDHs (15.1%), with excellent interobserver agreement (κ = 0.80; 95% CI, 0.7–0.9). The presence of contrast extravasation indicated a significantly increased risk of hematoma expansion (odds ratio, 4.5; 95% CI, 2.0–10.1; P = .0001) and in-hospital mortality (odds ratio, 7.6; 95% CI, 2.6–22.3; P = 0.0004). In a multivariate analysis controlled for standard risk factors, the presence of contrast extravasation was an independent predictor of aSDH expansion (P = .001) and in-hospital mortality (P = .0003).CONCLUSIONS:Contrast extravasation stratifies patients with aSDH into those at high risk and those at low risk of hematoma expansion and in-hospital mortality. This distinction could affect patient treatment, clinical trial selection, and possible surgical intervention.

Acute traumatic subdural hemorrhage carries a mortality rate of 68% in patients who are in a coma at the time of presentation.^1–4 The incidence of aSDH is approximately 21% in patients with severe TBI⁴ and decreases to 11% in patients with mild and moderate TBI.⁵ Mortality secondary to aSDH has been related to initial hematoma size, the presence of additional brain injury, midline shift, comatose state, and delay in hematoma evacuation >2 hours after arrival to the emergency department.^6,7 The decision to undertake surgical intervention versus expectant management of aSDH is based on hematoma size, the presence of midline shift, admission GCS score, and hematoma growth.⁸ Early hematoma evacuation (<4 hours) has been shown to improve intracranial pressure and therefore brain perfusion, with a decrease in mortality compared with delayed surgical intervention in comatose patients with severe TBI.⁴ Although a significant proportion of patients are treated nonoperatively (noncomatose patients and comatose patients with aSDH <10 mm in width and/or <5 mm of midline shift), a subset of these aSDHs will expand, necessitating delayed operative intervention. The strong relationship between mass effect and mortality suggests that hematoma expansion is probably deleterious for brain perfusion and clinical outcome.⁹ However, to date, no reliable predictors of aSDHs expansion in the initial 48 hours have been identified. Identifying such a predictor may be helpful in the clinical decision to triage patients to early surgical intervention versus expectant management.Prior studies have found that the presence of active contrast extravasation at CTA, defined as the spot sign, is a powerful predictor of hematoma expansion and in-hospital mortality in patients with primary intracerebral hemorrhage.^9–15 However, to date, no studies have assessed the frequency and predictive value of this important finding in patients with aSDH.In our emergency department, CTA of the head and neck is frequently performed in patients who present with craniocervical trauma to detect vascular injury.^15,16 Subsets of these patients also have an associated aSDH. This study aims to determine the frequency and predictive value for hematoma expansion and in-hospital mortality of the CTA contrast extravasation in patients with aSDH.     

监视器在CT增强检查中的应用价值

目的:评估监视器在监测增强CT扫描时对比剂外渗中的价值。方法:患者随机分采用监视器组(A组)和未用监视器组(B组),A组8603例,B组7985例,设定对比剂渗出>50ml为重度外渗,对比剂渗出<10ml为轻度外渗,观察A、B两组皮下对比剂外渗程度。结果:A组发生轻度外渗45例,重度外渗1例,B组发生轻度外渗33例,重度外渗18例。两组比较,其差异具统计学意义(P<0.05)。结论:应用监视器可早期发现穿刺、注射处的异常现象,从而防止重度对比剂外渗的发生。     

Gastric ulcer bleeding: diagnosis by computed tomography

A case of CT demonstration of a bleeding gastric ulcer is presented, in a patient with confusing clinical manifestations. Abdominal CT was performed without oral contrast medium administration, and showed extravasation of intravenous contrast into a gastric lumen distended with material of mixed attenuation. It is postulated that if radiopaque oral contrast had been given, peptic ulcer bleeding would probably have been masked. CT demonstration of gastric ulcer bleeding, may be of value in cases of differential diagnostic dilemmas.     

Central line pump infusion and large volume mediastinal contrast extravasation in CT

The use of multidetector CT scanners for CT angiography requires rapid injection of radiographic contrast media. Central venous catheters are now widely used for this purpose. Several complications may occur while using central venous access for rapid, large volume contrast injection such as catheter rupture and contrast extravasation. We describe a case in which inadvertent malposition of a central venous catheter led to a high volume extravasation of contrast in the mediastinum in a trauma patient.     

Intercostal artery injury manifested by a sentinel pleural clot

We present the imaging findings in a case of penetrating injury to an intercostal artery. The presence of the “sentinel clot sign” within the hemothorax and the extravasation of contrast material were the clues to the site of active bleeding. Active extravasation of contrast agent identified in CT scans may represent a life-threatening hemorrhage that usually requires emergency treatment.     

CTU在妇科手术后输尿管损伤中的诊断价值

目的:探讨CTU在妇科手术后输尿管损伤中的诊断价值。方法:回顾性分析10例经临床及影像检查确诊为妇科手术后输尿管损伤患者的影像学表现,8例行CT平扫、增强及延迟扫描,2例静脉尿路造影后行CT平扫,延迟时间6min～17h,平均3.41h。结果:10例均见输尿管下段损伤(左右各5例)、对比剂外渗;1例可见肾盂输尿管交界处对比剂外溢。阴道内积液、盆腹腔积液及盆腹腔积液并阴道内对比剂积聚各3例;1例肾周、腹膜后积液及对比剂外溢。5例尿性腹膜炎,4例伤侧输尿管扩张,3例(5个肾)肾轻度积水,1例尿性囊肿,1例腹膜后积尿伴炎症。结论:CTU能够清楚显示输尿管损伤的部位、程度、范围及其与周围组织的关系。     

Clinical and laboratory parameters in blunt pelvic trauma not associated with subsequent positive conventional angiography in patients with positive CTA

Emergency Radiology - This study evaluates clinical and laboratory parameters, as well as extravasation and hematoma size on CTA as potential predictors of conventional angiogram (CA) results. This...     

下消化道出血的诊断与介入治疗

目的：探讨介入方法在下消化道出血的诊断和治疗中的价值。方法：对11例经过内及钡剂检查来明确出血原因和部位的消化道出血患者，进行选择性动脉造影，通过显示对比例外溢、病理血管和肿瘤染色来确定出血原因及部位。同时对出血处用胶海棉栓塞或用保留导管灌注血管加压素止血。结果：全组11例，其中10例见对比剂外溢1例同时见肿瘤染色，7例显示病理血管。1例未能明确诊断。3例用明胶海棉栓塞治疗，8例采用保留导管灌汪血管加压素治疗，均达到止血效果。结论：介入治疗下消化道出血，可以快速作出定位诊断，且止血效果好，见效快，并发症少，既安全又可靠。     

Compartment syndrome of the forearm caused by contrast medium extravasation: A case report and review of the literature

Compartment syndrome is a rare but serious complication of contrast medium extravasation. To avoid permanent damage, it is important to recognize the symptoms quickly and immediately initiate treatment. We report a patient, who developed compartment syndrome of the forearm after extravasation of contrast medium and review the available literature on this subject. To our knowledge this is the first reported case of compartment syndrome of the forearm due to contrast medium application for a trauma CT in a patient that had no direct trauma to the affected limb.     

An In Vivo,MRI-Integrated Real-Time Model of Active Contrast Extravasation in Acute Intracerebral Hemorrhage

BACKGROUND AND PURPOSE:The “spot sign” or contrast extravasation is strongly associated with hematoma formation and growth. An animal model of contrast extravasation is important to test existing and novel therapeutic interventions to inform present and future clinical studies. The purpose of this study was to create an animal model of contrast extravasation in acute intracerebral hemorrhage.MATERIALS AND METHODS:Twenty-eight hemispheres of Yorkshire male swine were insonated with an MR imaging–guided focused sonography system following lipid microsphere infusion and mean arterial pressure elevation. The rate of contrast leakage was quantified by using dynamic contrast-enhanced MR imaging and was classified as contrast extravasation or postcontrast leakage by using postcontrast T1. Hematoma volume was measured on gradient recalled-echo MR imaging performed 2 hours postprocedure. Following this procedure, sacrificed brain was subjected to histopathologic examination. Power level, burst length, and blood pressure elevation were correlated with leakage rate, hematoma size, and vessel abnormality extent.RESULTS:Median (intracerebral hemorrhage) contrast extravasation leakage was higher than postcontrast leakage (11.3; 6.3–23.2 versus 2.4; 1.1–3.1 mL/min/100 g; P < .001). Increasing burst length, gradient recalled-echo hematoma (ρ = 0.54; 95% CI, 0.2–0.8; P = .007), and permeability were correlated (ρ = 0.55; 95% CI, 0.1–0.8; P = .02). Median permeability (P = .02), gradient recalled-echo hematoma (P = .02), and dynamic contrast-enhanced volumes (P = .02) were greater at 1000 ms than at 10 ms. Within each burst-length subgroup, incremental contrast leakage was seen with mean arterial pressure elevation (ρ = 0.2–0.8).CONCLUSIONS:We describe a novel MR imaging–integrated real-time swine intracerebral hemorrhage model of acute hematoma growth and contrast extravasation.

Intracerebral hemorrhage (ICH) accounts for 10%–30% of strokes and is the most deadly and disabling stroke type with little improvement in mortality seen during the past 20 years.¹ These characteristics underscore the importance of developing a better understanding of the pathophysiology of ICH formation and growth to facilitate the development of improved therapeutic agents or interventions.² The causative lesion in primary ICH is yet to be elucidated, though pathologic studies demonstrate focal vessel integrity loss in association with blood extravasation into the brain parenchyma.³ Following initial ICH formation, continuous^4,5 or delayed⁶ extravasation results in hematoma expansion,⁷ which is associated with early neurologic deterioration and significant mortality.⁸Several recent studies have shown an association between contrast extravasation (CE) detected on CTA, coined the CTA “spot sign,” and hematoma growth.^9–14 Prospective studies have demonstrated that contrast extravasation independently predicts a larger hematoma size and a poorer clinical outcome.^13,14 These are the first clinical studies to suggest a robust “real-time” imaging marker of hematoma expansion. Three clinical studies are presently enrolling patients dichotomized by the CTA spot sign to validate the prior study findings and to determine the therapeutic efficacy of recombinant factor VIIa or tranexamic acid.^15–17 A more recent study using dynamic spot sign imaging with a biphasic CT perfusion protocol¹⁸ has confirmed 2 patterns of contrast extravasation associated with significantly different rates of leakage. These patterns, comprising a brisker active extravasation (spot sign) and slower postcontrast leakage (PCL),¹⁹ are also demonstrated with early and late structural imaging,^10,19 dynamic CTA/CTP,¹⁸ and biphasic or repeat delayed CTA acquisitions.¹²Morphologic patterns and more recent studies illustrate that the spot sign is not an all-or-none phenomenon but constitutes a spectrum of extravasation.^18,19 The extravasation rate likely significantly impacts timely and clinically meaningful hemostasis.²⁰ A bleeding threshold likely exists beyond which prothrombotic treatment is futile, exposing patients to harmful adverse effects without hope of therapeutic benefit.²¹ Increasingly, new innovative surgical techniques are being developed to address contrast extravasation.²² Knowledge of the impact of the extravasation rate on therapeutic response is critical to stratify patients to the most appropriate therapies. An animal model of acute contrast extravasation in ICH could potentially inform the patient-selection process. We describe a novel MR imaging–integrated real-time swine model of acute hematoma growth and contrast extravasation.     

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。