[Significance of digital subtraction angiography in evaluating peripheral arteriovenous shunts in dialysis patients]. / Die Bedeutung der digitalen Subtraktionsangiographie zur Beurteilung peripherer arteriovenöser Shunts bei Dialyse-Patienten.

Direct and indirect examination of arteriovenous shunts was performed in 50 patients undergoing haemodialysis. The various methods of puncture of the vessels, the indications and the limitations of DSA are considered. The advantages of direct puncture of the arteriovenous shunt are emphasised. Puncture of the venous branch is almost without risk and allows immediate diagnosis. Only in a very few cases it will be necessary to perform the risky puncture of the arterial branch or the time-consuming central venous injection of a bolus of the contrast medium.

[Digital subtraction angiography and other non-invasive procedures for evaluating renal circulation and hypertension]. / Die digitale Subtraktionsangiographie (DSA) und andere nicht-invasive Verfahren zur Beurteilung der renalen Zirkulation und Hypertonie.

Nuclear medical techniques (such as isotope nephrograms, renal scintigrams) which are suitable as screening methods, have been unable to improve the diagnosis of reno-vascular hypertension. Amongst conventional procedures, the excretion urogram following a bolus injection was the most informative, particularly if performed together with nephro-tomography. Although ultrasound is of some use in evaluating the kidneys, the excretion urogram remains essential for the diagnosis of reno-vascular hypertension. Additional exposures and modifications (e.g. early phase urogram only add unnecessary radiation and cost without providing additional information. On the other hand, it would be useful to obtain digital subtraction angiograms of the renal arteries during the contrast injection. In this way, reliable information can be obtained on the cause of reno-vascular hypertension in more than 90% of patients. Similar results can be obtained by photographic subtraction (ISA). This should be used where DSA apparatus is not available. Angio-CT and sequential CT is not reliable for the diagnosis of renal artery stenosis. On the other hand, these methods provide density measurements or time-density curves of selected areas in the cortex or medulla of the kidney, which indicated abnormalities of the circulation and provide a comparison of the two sides.

[Digital intravenous subtraction angiography in the diagnosis of renal hypertension]. / Digitale intravenöse Subtraktionsangiographie in der Diagnostik des renalen Hochdrucks.

Indirect aortographies conducted in 123 patients via intravenous digital subtraction angiography (DSA) enabled satisfactory assessment of the renal arteries in 93% of the cases. The present state of the art, therefore, permits us to claim that DSA is of satisfactory diagnostic value in screening diagnosis of renal hypertension. It is well suited for confirming or excluding renal arterial stenosis and does not place any additional burden on the patient over and above the strain already exercised by excretion urography.

Comparison of nephroangiotomography, intravenous subtraction angiography and digital subtraction angiography in the diagnosis of renal hypertension.

Nephroangiotomography (NATG), intravenous subtraction angiography (ISA) and digital subtraction angiography (DSA) were compared with regard to their specificity and diagnostic value, their expenditure of time, equipment and staff as well as to their risk for the patients. The interpretation of NATG is inferior to ISA. The hitting quota of ISA and DSA is equal. The expenditure of time and staff for ISA is important, whereas the equipment for DSA is considerable; however, it has a wider use. In case of a low patient number, ISA delivers sufficient results in the diagnosis of renal hypertension with the advantage that it can also be performed in smaller radiological institutes.