64排128层螺旋CT肺动脉造影在诊断肺栓塞的应用

目的:探讨64排128层螺旋cT肺动脉造影(CTPA)在诊断肺动脉栓塞中的应用价值及内科治疗肺栓塞疗效.方法:对18例肺栓塞回顾性分析CTPA的影像学表现,并进行统计学分析.结果:18例554支血管中223支发生肺动脉栓塞(46.2％).54.3％肺叶以上动脉、65.1％肺叶动脉及42.0％肺段动脉受累.肺栓塞的CTPA表现:直接征象:①腔内充盈缺损:包括中心型充盈缺损(8.5％)、锐角附壁型充盈缺损(18.3％)、钝角附壁型充盈缺损(46.6％)及完全闭塞(1 9.3％).其中中心型及锐角型充盈缺损提示急性肺栓塞,钝角型充盈缺损及完全闭塞则为慢性肺栓塞的征象;②管腔突然狭窄(9.0％).间接征象:主动脉和(或)右侧叶问肺动脉扩张、胸腔积液、“肺少血”征、肺梗死、“马赛克”等.治疗后CTPA上肺动脉血栓部分或基本消失,肺动脉显示率显著提高,急性PE变化更明显,以中心性肺栓塞效果显著.结论:64排128层螺旋CTPA能够清楚显示PE的征象及其演变过程及治疗后效果,是诊断PE的一种可靠技术.     

A case report: Pulmonary venous malformation complicated with pulmonary hemorrhage

Pulmonary venous malformation is extremely rare. We present imaging and clinical findings of a 17-year-old male with multifocal subcutaneous venous malformations and multiple cystic lesions in the liver and spleen, suggestive of slow flow vascular malformation. In the right lung, chest radiography followed by chest CT demonstrated large tortuous pulmonary veins and cystic emphysematous changes. Tc99m-MAA (pertechnetate-labeled macroaggregated albumin) lung perfusion scan demonstrated only 3% of normal perfusion to the right lung, with no evidence of arteriovenous shunting. The child had diffuse intraparenchymal hemorrhage throughout the right lower and middle lobes and underwent resection. Pathology confirmed the diagnosis of venous malformation complicated with bleeding.     

MDCT angiography of the pulmonary arteries: intravascular contrast enhancement does not depend on iodine concentration when injecting equal amounts of iodine at standardized iodine delivery rates

To compare the impact of iodine concentration using two different contrast materials (CM) at standardized iodine delivery rate (IDR) and overall iodine load in 16-multidetector-row-CT-angiography (MDCTA) of the pulmonary arteries of 192 patients with known or suspected pulmonary embolism. One hundred three patients (group A) received 148 ml of a CM containing 300 mg iodine/ml (Ultravist 300, BayerScheringPharma) at a flow rate of 4.9 ml/s. Eighty-nine patients (group B) received 120 ml of a CM with a concentration of 370 mg iodine/ml (Ultravist 370) at a flow rate of 4.0 ml/s, resulting in a standardized IDR (approximately 1.5 gI/s) and the same overall amount of iodine (44.4 g). Both CM injections were followed by a saline chaser. Mean density values were determined in the pulmonary trunk, the ascending and the descending aorta, respectively. Applying repeated-measures ANOVA, no statistically significant differences between both MDCTA protocols were found (p = 0.5790): the mean density in the pulmonary trunk was 355 +/- 116 Hounsfield Units (group A) and 358 +/- 115 (group B). The corresponding values for the ascending and descending aorta were 295 +/- 79 (group A) and 284 +/- 65 (group B) as well as 272 +/- 71 and 262 +/- 70. In conclusion, the use of standardized IDR and overall iodine load provides comparable intravascular CM density in pulmonary 16-MDCTA for delivering contrast materials with different iodine concentrations.     

Klippel-Trenaunay综合征血管内硬化治疗的临床探讨

目的探讨Klippel-Trenaunay(KT)综合征血管内硬化治疗的疗效及安全性。方法6例KT综合征患者行顺行静脉造影、多普勒超声后行患肢动脉造影,并经动脉主干注入碘油平阳霉素乳剂,随访观察疗效及术后并发症。结果顺行静脉造影和多普勒超声显示单纯异常扩张浅静脉6例,深静脉无异常;动脉造影显示动脉二、三级分支增多,软组织内见染色影。术后并发症主要有肢体肿胀和感觉异常。随访8～40个月,5例肢体症状明显好转,1例症状反复。结论碘油平阳霉素乳剂血管内硬化治疗KT综合征能有效改善患肢症状。     

Prevalence of left atrial appendage pseudothrombus filling defects in patients with atrial fibrillation undergoing coronary computed tomography angiography

Background

Previous reports have shown that computed tomography (CT) is a useful, noninvasive test for detecting atrial thrombi. However, blood stasis in the left atrial appendage (LAA) of patients with atrial fibrillation (AF) may be a common cause for false-positive results.

Objectives

We retrospectively evaluated the prevalence of filling defects that may simulate thrombus in the LAA of patients with AF during routine coronary CT angiography (CTA).

Methods

The LAA of 7 patients with AF was studied for the presence of filling defects and compared with 250 healthy persons. LAA volume in the patients with AF was measured at 10 different cardiac phases and compared with 30 healthy patients.

Results

Of the 7 patients with AF studied with CTA, 5 were positive for LAA filling defects. Follow-up imaging studies, including transesophageal echocardiogram, contrast-enhanced magnetic resonance angiography, or delayed-CT, were negative for LAA thrombus. Of 250 patients without AF, CTA showed no evidence of LAA filling defects. Patients with AF had significantly larger LAA volumes at all cardiac phases measured compared with patients without AF (15.2 ± 6.93 mL compared with 6.85 ± 3.01 mL at atrial contraction [P = 0.0187], 17.4 ± 7.76 mL compared with 9.46 ± 3.43 mL at ventricular systole [P = 0.0351], and 14.5 ± 5.87 mL compared with 8.48 ± 3.10 mL at mid-diastole [P = 0.0341]). Compared with the healthy persons, the patients with AF showed reduced percentages of change in LAA volume when the atrial contraction phase was compared with other phases: 44.0% ± 25.6% compared with 16.5% ± 12.2% compared with ventricular systole (P = 0.0004) and 29.5% ± 23.7% compared with −1.63% ± 8.84% at mid-diastole (P < 0.0001).

Conclusions

Pseudothrombus filling defects are common in the LAA of patients with AF undergoing coronary CTA and should not be mistaken for real thrombus.     

颈椎闭合性创伤继发椎动脉损伤的研究进展

近年来国内外有关颈椎闭合性创伤合并椎动脉损伤的报道逐渐增多。献报道其发生率从19.7％～46％不等，并发现椎动脉损伤与单侧小关节移位、横突孔内有骨折片(即横突孔粉碎性骨折)之间有显相关性，旋转暴力可能是引起椎动脉阻塞的重要因素。椎动脉损伤在临床上可表现为视物模糊、晕厥、吞咽困难以及Wallenberg综合征等。磁共振血管成像(MRA)是一种诊断椎动脉损伤的无创检查，且易于在患行磁共振检查时同时进行，对闭合性颈椎创伤患，应常规行颅外血循环MRA检查，只有当患出现脑缺血症状时才考虑传统的血管造影。溶栓治疗对减低神经并发症及促进预后有待进一步研究，只有当患出现严重活动性出血或动脉介入影像学失败时才行手术治疗，外科暴露复杂并需对局部解剖知识非常了解。     

Future of cardiac computed tomography

Coronary computed tomography angiography (CCTA) has become an integral tool in the noninvasive diagnostic workup of patients with suspected coronary artery disease in both elective and emergency settings. Today, it represents a mature technique providing accurate, non-invasive morphological assessment of the coronary arteries and atherosclerotic plaque burden. Iterative reconstruction algorithms, low kV imaging, and single-heart beat acquisitions hold promise to further reduce dose requirements and improve the safety and robustness of the technique in several circumstances including imaging of heavily calcified vessels, patients with morbid obesity or irregular heart rates, and assessment in the emergency setting. However, it has become clear over recent years that cardiac radiologists need to take further steps towards the development and integration of functional imaging with morphological CCTA assessment to truly provide a comprehensive evaluation of the heart. Computed tomography myocardial perfusion imaging, including both dynamic and static dual-energy approaches, has demonstrated the ability to directly assess and quantify myocardial ischemia with simultaneous CCTA acquisition with a reasonable contrast medium volume and radiation dose delivered to the patient. In order to promote CCTA in the clinical and research environments, radiologists should prepare to embrace the change from morphological to functional imaging, furnishing all the necessary resources and information to referring clinicians.     

骨髓来源细胞移植对实验性肾小球肾炎小鼠的作用

目的：利用骨髓移植的方法观察骨髓来源细胞在小鼠实验性肾小球肾炎中的作用。方法：以绿色荧光蛋白（GFP）标记的C57BL／6转基因小鼠为供体,同种无标记小鼠为受体鼠,受体鼠在接受供体骨髓细胞前经亚致死剂量^60Co照射。并于移植5周后以尾静脉注射的方式接受竹叶青蛇毒注射;蛇毒注射后7、14、28、56d利用免疫组织化学和免疫荧光双重染色方法观察受体鼠肾脏内的GFP阳性细胞及受体鼠肾脏病理变化,其中一组受体鼠在蛇毒注射后接受连续1周的粒巨系一集落刺激因子（GM-CSF）腹腔注射,观察GM-CSF对骨髓来源细胞及受体鼠的影响。结果：无论有无蛇毒损伤,荧光显微镜下受体鼠肾脏内均未见明亮的绿色荧光。GFP免疫组织化学可见所有受体鼠的肾小管上皮内均有少量细胞质棕褐色、细胞核大且紫蓝的GFP阳性细胞,包括那些骨髓移植后无蛇毒损伤的受体鼠;肾小球内也可见上述细胞,但在无蛇毒损伤的受体鼠内肾小球内未见上述细胞;激光共聚焦显微镜未见到明显双染色阳性的细胞,从形态上证实肾小球内的这些GFP阳性细胞大多为血细胞。那些接受GM-CSF注射的受体鼠肾脏内,GFP阳性细胞没有明显增加,而且肾脏损伤恶化,表现为蛇毒注射后1周出现了明显的局灶性节段性肾小球硬化。结论：骨髓来源细胞在蛇毒诱导的系膜增生型肾小球肾炎小鼠肾脏内向肾小管和肾小球细胞均可少量转化,但由于转化率低及肾小球结构的复杂性,向肾小球细胞的转化更加不易被识别;GM-CSF注射未能增加外源性骨髓细胞向肾脏实质细胞的转化而使受体鼠肾脏损伤恶化,于病程早期出现了局灶性节段性肾小球硬化。