Abdominal angiography with stereoscopic magnification

A new technique for stereoscopic magnification angiography has been developed and combined with routine abdominal angiography. The technique utilizes two divergent x-ray beams at a 34° angle, with a 3.5 cm focal spot separation at a 94 cm focalfilm distance, produced by a synchronous arc rotation of a microfocus x-ray tube. The synchronous motion of the tube is maintained by using an electromechanical device. A magnification factor of 2.0 to 3.0 is used, and 12 films are exposed in a series, the fastest sequence being 1.5 films per second. This technique provides the advantages of magnification and stereoscopic angiography, with excellent demonstration of small arterial branches and abnormal vascularity in three dimensions.     

A prospective,comparative study of ventilation-perfusion scintigraphy and clinical evaluation versus digital subtraction angiography in acute pulmonary thromboembolism

Patients with symptoms of acute pulmonary thromboembolism (APE) of short duration were investigated with digital subtraction angiography (DSA) and ventilation/perfusion lung scintigraphy (V/Q scan), and a standardised clinical evaluation was performed. Forty-six angiograms (96%) were diagnostic at the segmental level and were used as reference. In all V/Q scans classified as normal or of high probability for APE, a complete agreement with DSA was found. In scan categories with low or intermediate probability, where the incidence of APE was 32%, there was considerable inter-observer disagreement. Clinical assessment alone was of limited value, but in patients with low clinical suspicion no APE was found. The results indicate that normal and high probability V/Q scans are very reliable for excluding and identifying APE, respectively, but also that fairly large APE cannot be diagnosed with lung scanning. Subdivision of V/Q scans into more than three categories (normal, high probability and inconclusive) seems to be of no practical value. Using a pulsed sequence technique, high frame rate and central injection, DSA is a valuable clinical tool for diagnosing APE down to the segmental level. Correspondence to: B. Hedlund     

Digital subtraction angiography in abnormal perfusion scintigraphy of the lungs

A normal lung perfusion isotope scan can exclude pulmonary emboli. However, the demonstration of lung emboli presents problems, as an abnormal lung perfusion scan can have various causes. Some of these can be excluded if the perfusion scan is assessed in combination with a chest X-ray and a ventilation scan. In this study, 21 patients with an abnormal perfusion scan were also examined using digital subtraction angiography (DSA) of the lungs. With the help of DSA it was possible to differentiate between the various causes of a lung perfusion defect on the isotope scan by having a sufficiently reliable pulmonary angiogram. From experience it appears that the quality of the pulmonary angiogram confined to the first three divisions obtained with DSA, is comparable with that from a conventional pulmonary angiogram. A perfusion isotope scan is the initial screening modality for suspected lung emboli, if this shows an abnormality, DSA seems to be indicated as the next step.     

新生儿肺炎的DR影像表现

目的探讨新生儿肺炎的主要临床表现和DR胸部X线平片的影像表现,以及二者之间的特点和相互关系,并提高对该疾病的进一步认识。方法前瞻性分析60例新生儿肺炎的主要临床表现和DR胸部表现。结果本组患儿中支气管肺炎38例（63.3％）,大病灶肺炎3例（5％）,间质性肺炎8例（13.3％）,大叶或节段性肺炎3例（5％）,吸入性肺炎5例（8.3％）,气胸3例（5％）。绝大多数患儿表现为肺纹理增多和肺门阴影模糊。结论通过肺部症状与DR胸片表现之间关系的分析河提高本病诊断率。     

螺旋CT肺动脉造影诊断肺小动脉血栓的实验研究

目的：评价螺旋CT肺动脉造影（spiral CT pulmonary angiography，CTPA）诊断犬肺小动脉血栓栓子（直径2.5-3.5mm）的应用价值。方法：23条实验犬行CTPA空白对照后，制成犬自体血块肺动脉栓塞模型，先后行CTPA与X线肺动脉造影（X-ray pulmonary angiography，XPA）检查，由2名医生在工作站上分析所获图像，并与犬肺病理解剖结果对照，评价CTPA与XPA对肺动脉血栓栓塞的诊断价值。结果：22条犬完成实验全过程，病理解剖发现肺动脉内栓子110个，与人工注入栓子数目相符，均位于肺动脉的段或亚段水平，其中107个位于扫描野内。CTPA发现栓子90个，诊断肺动脉内小血栓栓子的敏感度为84.1％，阳性预测值为93.8％；XPA发现栓子82个，敏感度为76.6％，阳性预测值为94.3％。结论：CTPA对实验性肺小动脉血栓栓子有较高的诊断价值。     

Pulmonary arteriography: The importance of multiple projections

Pulmonary arteriography is a highly specific procedure for the diagnosis of vascular abnormalities within the lungs. However, no single projection canalways be diagnostic for abnormalities in any of the pulmonary arteries. We emphasize the anatomic basis for the initial projection on pulmonary arteriography, as well as the necessity for further studies in different projections if the first study demonstrates no abnormality.     

CT肺血管成像对急性大面积肺栓塞患者的动态分析价值

目的 探讨CT肺血管成像(CTPA)对大面积肺栓塞患者的动脉栓塞程度及右心功能的动态分析价值.方法 回顾性分析23例大面积肺栓塞患者的CTPA资料,分析治疗前、治疗后24 h及14 d时的CTPA肺动脉栓塞指数及右心功能参数,采用单因素方差分析、LSD检验和X2检验分析治疗前后的变化,并采用Pearson法分析肺动脉栓寨指数与右心功能参数之间的相关性.结果 CTPA肺动脉栓塞指数在溶栓治疗后逐渐减小,Qanadli和Mastora评分在治疗前(分别为50.0、46.5分)与治疗后24 h(分别为42.5、12.1分)比较差异有统计学意义(t值分别为2.830、6.493,P值均<0.01);治疗后24 h与治疗后14 d(分别为25.0、8.4分)比较差异有统计学意义(t值分别为4.640、4.299,P值均<0.01).治疗后24 h,右心室最大短轴直径(4.58 cm)及横截面积(23.10 cm2)明显减小,左心室最大短轴直径(4.41 cm)及横截面积(26.37 cm2)明显增大,双侧心室最大直径比(1.07)和面积比(0.94)明显减小,与上述各指标治疗前相比(分别为5.07 cm、25.42 cm2、3.57 cm、20.17 cm2、1.59,1.38)差异有统计学意义(t=2.081～4.959,P值均<0.05);治疗后24 h,肺动脉收缩压(40.92 mm Hg)明显变小,与治疗前(58.61 mm Hg)相比差异有统计学意义(t=2.824,P<0.01);治疗前与治疗后24 h,CTPA肺动脉栓塞指数与右心功能参数间均有不同程度的相关性(r=0.034～0.598,P值均<0.01).结论 CTPA可以动态观察急性肺栓塞的肺动脉阻塞程度及右心功能的变化,为临床治疗提供重要的信息.     

64层螺旋CT肺动脉造影在肺动脉栓塞诊断中的应用

目的 探讨64层螺旋CT肺动脉造影(CT pulmonary angiography,CTPA)对肺动脉栓塞(pulmonary embolism,PE)的诊断价值.方法 回顾分析24例肺动脉栓塞患者的64层螺旋CT增强图像,将原始图像复制到EBW4.0工作站,对肺动脉主干及分支进行多平面重建(MPR),最大密度投影(MIP)及容积重建(VR)分析.结果 24例患者中,共检出了76处肺动脉及其分支的栓子.其中,左、右肺动脉主干14处(右主干10处、左主干4处),肺叶动脉24处,肺段动脉26处,亚肺段动脉12处.CT表现为肺动脉主干或分支内混合性、附壁性、中心性充盈缺损,可分为完全性或部分性.结论 64层CTPA具有准确、高效、无创等优点,可直观、立体地观察到肺动脉血栓的大小、分布、范围及类型,是临床诊断及观察疗效的首选方法,有望成为肺动脉栓塞检查的“金标准”.     

肺动脉CT成像增强技术的优化研究

目的 推导CT肺动脉成像(CTPA)中精确计算对比剂用量公式,并评价其应用于小剂量对比剂预注射法CTPA影像的质量与临床应用的意义.方法 搜集经CTPA检查的连续27例患者小剂量对比剂实验注射形成的TDC数据,分析从注射对比剂开始至上腔静脉下端增强峰值所用时间占注射开始至肺动脉增强峰值时间的比值,测算上腔静脉下端在扫描范围中的水平,推导出计算对比剂使用总量预计算公式( DTs/3+ STs/2).将临床怀疑但CTPA未发现为肺动脉栓塞(PE)的68例患者纳入研究,按检查奇、偶周数分为2组:A组26例,传统增强跟踪自动触发扫描组;B组42例,小剂量对比剂预注射组.在CTPA影像中,2组分别测量右肺动脉主干(RMPA)和右上肺静脉(RUPV)、右肺下叶后基底段动脉(RLPA)和伴行右下肺静脉(RLPV)、RMPA与升主动脉(AA)的CT值,计算每对血管CT值差值,对影像进行评分,并计算对比剂用量、上腔静脉内对比剂硬化伪影分级.采用f检验、x2检验与秩和U检验,分析2组间各值差异的统计学意义.结果 对比剂开始至注射到上腔静脉增强时间与至肺动脉增强时间比为0.65±0.09.A、B2组间RMPA、RLPA的CT值分别为(301±117)、(329±122)与(283±95)、(277±98)HU,差异无统计学意义(t值分别为1.060、2.056,P值均＞0.05),但肺动静脉血管对之间的CT值差(中位数分别为22.5、58.0与170.5、166.5 HU),2组间差异有统计学意义(U=292,P=0.001与U=325,P=0.005);影像评分为5分与4分者B组为85.7％( 36/42)优于A组(46.1％,12/26),差异有统计学意义(x2=14.175,P＜0.01);上腔静脉内对比剂伪影分级(1～3级)B组(分别为34、7、1例)明显好于A组(分别为11、10、5例),差异有统计学意义(x2=10.714,P=0.002);对比剂实际注射总量A组为(87.6±7.3)ml,B组为(40.0±5.4) ml,差异有统计学意义(t=-2.152,P＜0.01).结论 采用小剂量对比剂预注射法与传统方法比较,CTPA影像质量与强化程度一致,但可明显降低肺静脉内对比剂的浓度,对肺动脉的辨识更容易,而且可明显减少上腔静脉内对比剂的硬化伪影对右肺动脉观察的干扰,降低对比剂的用量,有利于减轻患者对比剂肾病的危险.     

16层CT血管造影在肺动脉栓塞诊断中的应用价值

目的 探讨16层CT肺动脉造影对肺动脉栓塞(PE)的诊断价值.方法 对24例PE患者行16层CT血管造影检查,采用多平面重建(MPR)、最大密度投影(MIP)、容积再现(VR)多种图像后处理技术,并结合轴位图像进行综合分析.结果 24例均能显示肺动脉栓塞的部位、范围、局部管腔狭窄程度,19例急性肺动脉栓塞的直接征象为“截断征”、“双轨征”;5例慢性肺动脉栓塞主要表现为肺动脉管腔内偏心性、附壁性的充盈缺损.结论 16层CT血管造影是诊断肺动脉栓塞及其溶栓疗效评价和随访最有效的无创性检查方法之一.     

Non-traumatic thoracic emergencies: CT diagnosis of acute pulmonary embolism: the first 10 years

Over the past 10 years, spiral CT angiography of the pulmonary arteries has reached a high accuracy in the evaluation of pulmonary embolism. Major advantages of CT compared with ventilation/perfusion lung scintigraphy and pulmonary angiography is direct visualization of clots in the pulmonary arteries, and to provide alternative findings or diagnosis. The recent introduction of multislice CT has improved the evaluation of peripheral pulmonary arteries, enabling high-resolution CT examinations over the entire thorax in a short breathhold. The examination techniques, imaging findings, pitfalls, and results of CT in the diagnosis of pulmonary embolism are reviewed in comparison with other diagnostic tests.     

The value of bedside Lung Ultrasonography in diagnosis of neonatal pneumonia

Purpose

The aim of this prospective study was to assess lung ultrasonography as an alternative to bedside radiography for the diagnosis of neonatal pneumonia.

Patients & methods

The study was performed on 75 neonates admitted during the period from October 2011 to October 2012 in the NICU of Cairo University Pediatric Hospital presenting with clinical picture of pneumonia. Chest X-rays and lung US were done.

Results

Chest X-ray findings denoting lung infections were present in 64 cases (85.3%), and the remaining 11 cases (14.6%) had a free chest X-ray. Ultrasonography revealed pneumonic patches in 68 patients (90.6%), 7 (9.3%) had free US scans. US and chest X-rays detected pneumonic patches in 64 cases (85.3%), US detected pneumonic patches in 18 cases (24%) with chest X-rays having signs of chest infections other than pneumonic patches and in 4 cases (5.3%) with clear chest X-rays.

Conclusion

Bedside lung ultrasonography is highly sensitive, specific, and reproducible for ruling out underlying pneumonic process as well as in early detection and follow up of possible complications and can be considered an attractive alternative to bedside chest radiography and thoracic computed tomography with minimal radiation exposure.     

Peripheral pulmonary arteries: identification at multi-slice spiral CT with 3D reconstruction

Our objective was to analyze the peripheral pulmonary arteries using thin-collimation multi-slice spiral CT. Twenty consecutive patients underwent enhanced-spiral multi-slice CT using 1-mm collimation. Two observers analyzed the pulmonary arteries by consensus on a workstation. Each artery was identified on axial and 3D shaded-surface display reconstruction images. Each subsegmental artery was measured at a mediastinal window setting and compared with anatomical classifications. The location and branching of every subsegmental artery was recorded. The number of well-visualized sub-subsegmental arteries at a mediastinal window setting was compared with those visualized at a lung window setting. Of 800 subsegmental arteries, 769 (96%) were correctly visualized and 123 accessory subsegmental arteries were identified using the mediastinal window setting. One thousand ninety-two of 2019 sub-subsegmental arteries (54%) identified using the lung window setting were correctly visualized using the mediastinal window setting. Enhanced multi-slice spiral CT with thin collimation can be used to analyze precisely the subsegmental pulmonary arteries and may identify even more distal pulmonary arteries. Electronic Publication     

Pulmonary angiography: a safe procedure with modern contrast media and technique

Pulmonary angiography (PA) for decades has been accepted as the gold standard for the diagnosis of pulmonary embolism (PE). Apprehensions that the procedure is expensive, invasive and thus associated with both fatal and non-fatal complications has more or less limited its use to patients presenting a non-diagnostic lung scan. However, this opinion originates from earlier studies. Increasing clinical demands for faster and safer diagnostics, together with improved techniques and safer contrast media, has led to an increased use of PA. In order to evaluate the complication rate, we retrospectively studied the case records of 707 consecutive patients who had undergone PA. During 1990–1994, 728 patients underwent PA at Danderyd and Huddinge University Hospital. Selective pulmonary angiography (cine or digital subtraction angiography), non-ionic, low-osmolar contrast media and modern pigtail catheters were used. Standard volumes were 40 ml at 2 s for each injection. Pressure measurements were made in 376 patients. A test injection was made in all patients in order to assess the flow rate. Experienced radiologists as well as residents performed the examinations and a total of 707 angiography protocols and clinical records were available for review in search of complications associated with the procedure. No deaths occurred. One major non-fatal complication (bleeding in the groin requiring surgery) was reported in one case. Moderate/minor complications (i. e. transient angina and cardiac failure, minor haematomas, urticaria) occurred in 10 patients (1.4 %). With modern contrast media and technique, pulmonary angiography is a safe procedure. Received 16 December 1996; Revision received 5 May 1997; Accepted 26 May 1997     

支气管动脉和肺动脉多层螺旋CT血管造影对肺癌血供的研究

目的 用支气管动脉(BA)和肺动脉(PA)多层螺旋CT血管造影(BA—MSCTA和PA—MSCTA)的方法进一步研究肺癌血供。方法 对16例原发性肺癌患者分别行支气管动脉和肺动脉数字减影血管造影(BA—DSA和PA—DSA)后，留置导管行PA—MSCTA和BA—MSCTA，判定支气管动脉和肺动脉对肺癌的血供。结果 PA—MSCTA和PA-DSA上均未见明确的肺动脉供应肿瘤，也未见肿瘤内部和边缘有肿瘤血管和肿瘤染色。BA—DSA和BA—MSCTA上均可见肿瘤内部杂乱无章的肿瘤血管影，以及对比剂进入肿块内部。PA—MSCTA清晰显示肿块内部及其与肺动脉的关系。BA—MSCTA上5例可见肿瘤内血管和对比剂部分缺损，7例可见肺门和(或)纵隔淋巴结染色，其中BA-DSA上有肺门和(或)纵隔淋巴结染色的4例中，3例染色的淋巴结个数增多。结论 MSCTA是研究肺癌血供的较好方法，该研究再次证明肺动脉不参与原发性肺癌的血供，但应注意多支体循环供血的可能。     

多层螺旋CT对周围肺动脉显示能力的研究

目的比较多层螺旋CT肺动脉造影不同层厚重建对周围肺动脉的显示能力. 资料与方法 21例无肺部疾患和血栓病史的患者行CT肺动脉造影检查,均用0.75 mm准直扫描,分别用0.75 mm/0.5 mm（层厚/层间距）（A组）、1.0 mm/0.6 mm（B组）、1.5 mm/1.0 mm（C组）重建,记录每例患者3种不同重建层厚对段肺动脉、亚段肺动脉、5级和6级肺动脉的显示情况及血管不能显示的原因. 结果 3组人均肺段动脉的显示率均为96.45%（19.29/20）;人均亚段动脉显示率分别为94.42%、93.44%、91.13%,3组间均无显著性差异;A、B、C组对第5级肺动脉的人均显示率分别为80.44%、73.47%、59.02%,A组与C组有显著性差异（P＜0.01）,B组与C组间有显著性差异（P＜0.05）;6级肺动脉3组人均显示率分别为33.75%、31.69%、23.56%,A组与C组有显著性差异（P＜0.01）.段肺动脉不能分析的主要原因是解剖变异（53.33%）和心脏搏动伪影（40%）;A、B组亚段肺动脉不能分析的主要原因是解剖变异和心脏搏动伪影,C组的主要原因是部分容积效应（43.84%）与A组比较有显著性差异（10.87%）（P=0.015）;3组对5级和6级肺动脉不能分析的主要原因均为部分容积效应. 结论多层螺旋CT肺动脉造影0.75 mm、1.0 mm、1.5 mm重建层厚对段肺动脉和亚段肺动脉均有很好的显示率,A、B组对5级肺动脉的显示率也较好.影响亚段肺动脉显示的主要原因是解剖变异和心脏搏动伪影.1.0 mm重建层厚可满足肺动脉的观察和图像处理的需要.     

64层螺旋CT血管造影对肺动脉栓塞的临床诊断价值

目的探讨64层螺旋CT血管造影对肺动脉栓塞的临床诊断价值。方法 30例患者行肺动脉CTA检查,并采用多平面重建（MPR）对原始数据进行后处理。结果 30例均能显示肺栓塞的部位、范围及局部管腔狭窄程度,CT表现为肺动脉内不规则斑块状、附壁样缺损,周围有或无高密度对比剂包绕。结论 64层螺旋CT血管造影是临床诊断肺动脉栓塞最有效的无创性方法之一。     

The value of pulmonary angiography for the differential diagnosis of pulmonary embolism

The aim this study was to evaluate potential additional information of pulmonary angiography in patients with suspected pulmonary embolism and non-diagnostic lung scan findings. In a series of 150 patients who underwent pulmonary angiography for suspected venous thromboembolism, the images for potential alternative diagnoses other than pulmonary embolism were evaluated. All patients had non-diagnostic lung scan findings. Angiography was performed both by conventional and by digital subtraction angiography techniques. Images were evaluated by at least two experienced readers. Angiograms were scored for both presence or absence of pulmonary embolism, as well as other diagnoses. Pulmonary embolism was proven in 40 patients (27 %) and excluded in 105 patients (70 %), whereas non-interpretable images were obtained in 5 patients (3 %). A range of alternative diagnoses were detected by angiography: atelectasis (n = 24), pleural effusion (n = 15), pneumonia (n = 11), emphysematous bullae (n = 8), neoplasm (n = 3), atrial septum defect (n = 2), chronic thromboembolism (n = 1), and other diagnoses (n = 3). Overall, only 54 patients (36 %) had completely normal angiograms. Although pulmonary angiography remains the reference method for the diagnosis of pulmonary embolism, one has to be aware of other, often unexpected, but equally important findings which could influence the management of the patient. This aspect of pulmonary angiography has been insufficiently emphasized in the literature. Received: 2 April 1998; Revision received: 22 July 1998; Accepted: 4 November 1998     

Pulmonary magnetic resonance angiography

In the past few years magnetic resonance angiography (MRA) of the pulmonary vasculature has advanced from a research tool to a clinically relevant imaging modality. Early 2D phase-contrast and time-of-flight (TOF) sequences without the use of contrast agents were time-consuming and limited by considerable imaging and motion artifacts. Since the introduction of MR scanners with stronger gradients (> 20 mT/m) and contrast-enhanced techniques, imaging of the pulmonary vasculature with adequate spatial resolution within a single breathhold is now possible. In the detection of pulmonary embolism in the lobar or segmental arteries, contrast-enhanced MRA is now on the verge of being considered an established modality, possibly competing with conventional pulmonary angiography and contrast-enhanced helical CT. In the future, utilization of phased-array torso coils, the application of navigator pulse sequences, and 3D time-resolved ultrafast MRA will overcome the final limitations of current techniques. Blood-pool MR contrast agents may provide a “one-stop-shopping” approach to the investigation of lower extremity veins and pulmonary arteries in venous thromboembolism.     

肺灌注/通气显像与肺动脉造影诊断肺动脉栓塞的对比研究

目的评价核素肺通气/灌注(V/Q)显像在肺动脉栓塞(PE)诊断中的价值。方法临床疑有PE患者30例,男女各15例,平均年龄(38.2±13.9)岁。均行胸部X线片检查、核素V/Q显像和肺动脉造影。11例患者在行肺灌注显像时,选择双侧足背静脉注射肺灌注显像剂,同时完成双下肢静脉显像。结果30例患者中22例V/Q显像示不相匹配的肺叶、肺段或多发亚肺段的放射性分布稀疏或缺损,提示为PE;但肺动脉造影证实22例中20例为PE。8例患者的V/Q显像为相匹配的肺叶、肺段或多发亚肺段的稀疏或缺损,提示不是PE,与肺动脉造影结果一致。核素V/Q显像诊断PE的灵敏度为100%（20/20例）,特异性为80.0%（8/10例）,准确性为93.3%（28/30例）。X线胸片和核素下肢静脉显像有助于PE的正确诊断。结论多数PE患者通过核素肺V/Q显像结合X线胸片可以作出明确诊断,少数肺V/Q显像与临床表现不符的患者需行肺动脉造影。