Digital Subtraction Angiography Technique Research Articles

Neurologic complications of cerebral angiography. A retrospective study of complication rate and patient risk factors.

To evaluate the neurologic complication rate and individual patient risk factors in cerebral angiographies using the digital subtraction angiography (DSA) technique and non-ionic contrast media in a department with many radiologists in training. A retrospective study of 483 cerebral angiographic examinations in 454 patients was carried out. The following parameters were registered: sex and age of the patient, indication for the angiography, cerebral CT diagnosis, laboratory data, type of anesthesia, type of angiographic procedure, level of training of the angiographer, number of participating angiographers, type of catheters, number of vessels catheterized, number of exposures, use of compression series, total amount of contrast media, diagnosis of the angiogram, complications and duration of complications. The frequency of all neurologic complications was 2.3%, the frequency of persistent neurologic deficits was 0.4%. Non-neurologic complications were observed in 14.7% of the examinations. Of all the parameters studied, the only factor that significantly increased neurologic risk was a normal angiogram, a finding we are inclined to ascribe to chance. Performance of a compression series showed a trend towards increasing the neurologic risk. This study showed a complication rate of persistent neurologic deficits of 0.4% which is in accordance with other recent reports. A compression series should not be performed routinely, but only on special indication. This study confirms the low risk of cerebral angiography when performed in a neuroradiological department using the DSA technique and non-ionic contrast media.

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.

Screening for unruptured familial intracranial aneurysms. A decision analysis.

Decision analysis is used to assess the decision to screen for unruptured intracranial aneurysms (IAs) in two affected families, and to formulate guide-lines for similar decisions. Four strategies are compared: "no screening", "screening directly", "screening twice", and "screening later". Intravenous and intra-arterial digital subtraction angiography techniques (iv-DSA, ia-DSA) are considered. Life years lived with and without disability are computed for each strategy. Loss of life expectancy with and without discounting and quality correction is used as an outcome measure. "No screening" is the preferred strategy when population based estimates of the prevalence of IAs are used. Thus, the results of this analysis provide no justification for screening patients without a familial history. But a physician who thinks that the risk of an IA is increased may rightly decide for screening, especially when the patient is aged 40 to 60. Ia-DSA is preferable over iv-DSA. A scenario analysis suggests that screening with magnetic resonance angiography is only slightly better than with ia-DSA, because the complication rate of screening plays a minor role in the analysis.

Digital subtraction angiography in preoperative examination of congenital hand malformations

Since 1971, we have carried out in our department systematic angiographic research on cases of congenital hand deformities to determine how the vascular pattern takes part in the global anatomic deformity of the malformed hand.” 2 From our point of view, proper evaluation of the blood supply is important to classify the congenital malformation, complete the patient’s documentation, and select the correct surgical planning when treating a malformed hand. Since 1981, we have performed a digital subtraction angiography technique that has well-known advantages over traditional techniques: it allows better visualization, provides a real-time hemodynamic evaluation, uses lower doses of contrast medium, and gives the possibility to register the entire examination on a magnetic tape.3-9 Technique. In children under 14 years of age, we prefer to perform the examination under general anesthesia; in older patients a brachial plexus block, if indicated, can be performed. To prevent allergic reactions, 4 mg of betamethasone sodium phosphate is given intravenously the evening before the test; the day of the examination 1.5 mg of betamethasone sodium phosphate and 10 mg of chlorpheniramine maleate are given intravenously. The contrast medium used is iodated or noniodated (iopamidol or iohexol). The humeral artery is exposed at the elbow to avoid problems relating to percutaneous injections such as hematomas, intimal damage, infiltration of contrast medium in the forearm’s soft tissues, and damage to the median nerve. If ex-

Use of digital subtraction angiography for evaluation of vascular access for hemodialysis.

We used digital subtraction angiography (DSA) with conventional methods of contrast injection to evaluate 13 failing vascular accesses in 12 patients undergoing hemodialysis. DSA results were confirmed in all cases by surgical findings and/or clinical follow-up. The DSA technique is extremely flexible and rapid and requires the injection of only small amounts of dilute contrast with much less patient discomfort. DSA is an excellent alternative to film screen angiography for the evaluation of vascular access complications.

Outpatient DSA in cerebrovascular disease using transbrachial arch injections.

Experience with intravenous digital subtraction angiography (DSA) has proven disappointing in the outpatient evaluation of cerebrovascular disease. Vessel superimposition, patient motion, and poor vascular opacification all prevent definitive studies in a significant percentage of patients. These problems were addressed by turning to an intraarterial outpatient DSA technique composed of several elements: (1) right transbrachial catheterization of the ascending aorta using a thin, multiple side-hole, straight catheter; (2) arch injections of relatively small volumes of contrast material; (3) pulsed digital image acquisition with multiple projections; and (4) a limited period of postprocedure observation. A total of 43 outpatients and 16 inpatients was studied in this manner with only two complications, both local. Images of definitive quality and completeness were obtained in 82%-98% of cases, and included the major intracranial as well as the extracranial vessels and their circulatory dynamics. Because the iodine load per injection was relatively low, up to 10 angiograms per case were available for delineating superimposed anatomy and motion degradation. Variations in cardiac output had little impact on image quality, and the average case required less than 60% of the contrast load routinely used for intravenous DSA. The transbrachial approach proved as safe and convenient as intravenous DSA but was more thorough and dependable.

Demonstration of pancreatic parenchyma by digital subtraction techniques during endoscopic retrograde cholangiopancreatography

This paper reports the feasibility of using digital subtraction angiography techniques during endoscopic retrograde cholangiopancreatography to obtain greater detail of pancreatic structure. The pancreatic duct was filled in 23 of 27 cases attempted and in 17 cases parenchymal detail was obtained. Filling defects due to neoplasm were clearly defined and the changes of chronic pancreatitis visualised. The technique seems valuable for small lesions but may carry a higher risk of producing pancreatitis.

Hybrid intravenous digital subtraction angiography of the carotid bifurcation.

A hybrid digital subtraction angiography technique and noise-reduction algorithm were used to evaluate the carotid bifurcation. Temporal, hybrid, and reduced-noise hybrid images were obtained in right and left anterior oblique projections, and both single- and multiple-frame images were created with each method. The resulting images were graded on a scale of 1 to 5 by three experienced neuroradiologists. Temporal images were preferred over hybrid images (average score = 3.2 and 2.4, respectively). The percentage of nondiagnostic examinations, as agreed upon by two readers, was higher for temporal alone than temporal + hybrid (4 and 1, respectively). In addition, also by agreement between two readers, temporal + hybrid images significantly increased the number of bifurcations seen in two views (87%) compared to temporal subtraction alone (64%).

Arterial Hypertension: Pathogenesis, Diagnosis, and Therapy

This is an excellent reference work suitable for all clinicians dealing with hypertension. In 35 chapters the pathogenesis, diagnosis, and treatment of the disease are discussed in detail by a group of distinguished experts, the majority from West Germany. There are areas that are of particular note in this book. These include chapters providing an overview of the entire subject, the role of the CNS in hypertension, the kallikrein-kinin and prostaglandin systems, and central hemodynamics and cardiac function in hypertension. In the section dealing with elevated blood pressure in pregnancy, a controversial and important subject, an expansion of the discussion on therapy would have been welcome. The discussion of childhood hypertension includes a full presentation of coarctation of the aorta, in addition to broader aspects of the entire topic. The chapter on radiological methods of diagnosis could have benefited from a portion dealing with the technique of digital subtraction angiography