Biomedical subjects
Publications and source records attributed to C Ranke.
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14 femoral arteries of twelve patients with peripheral arterial occlusive disease (Fontaine stage II: n = 4, stage III/IV: n = 10) were investigated before, immediately after a series of 26 (ten to 52) intraarterial infusions with prostaglandin E1, and 30 weeks later. Using combined B-mode and pulsed Doppler (duplex) ultrasound blood flow measurements were performed in the common femoral, the superficial femoral, and the deep femoral artery. There was a significant decrease of resting blood flow volume in the common femoral artery after therapy (418.5----362.2 [p less than 0.01]----324.5 ml/min [p less than 0.05]) in the group of patients treated successfully. The peak flow (maximum value of blood flow volume during reactive hyperaemia) in the common femoral artery increased significantly after therapy (597.3----779.1 [p less than 0.05]----843.7 ml/min). The increase of peak flow correlated well with clinical improvement. Other parameters (blood flow velocities, pulse rise time, pulse decrease time, pulsatility index) changed without correlation to clinical outcome. The increase of peak flow after therapy might be caused by an improved collateral circulation, and the decrease of resting blood flow might be due to metabolic effects of prostaglandin E1 (improved oxygen utilization).
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Ultrasound Doppler sonography is the most important tool in the assessment of peripheral arterial occlusive disease. The determination of systolic ankle pressure gives an useful overview of the degree of the disease. In a normotensive patient with a systolic blood pressure of 140 mm Hg systolic ankle pressures between 100 and 140 mm Hg are present when the occlusive disease is in the stage of good compensation. Severe claudication will appear with ankle pressures between 70 and 95 mm Hg, lower values are indicating a critical limb ischaemia. Treadmill exercise is helpful for documentation of painfree and maximal walking distances. When a patient is suggested to be treated by percutaneous transluminal angioplasty or bypass surgery a duplex sonography or angiography is mandatory. In evaluating the Raynaud's phenomenon under the noninvasive techniques capillaroscopy of the nailfold is a useful tool. The diagnosis of thromboangiitis obliterans is usually established by clinical criterias. The radiographic findings may give important hints. In many cases of acute arterial occlusions angiography is necessary for finding the optimal therapy. The aneurysm of the abdominal aorta will be evaluated by ultrasound and computer tomography.
Using a pulsatile model of tubes, duplex-sonographic measurements of flow were compared with actual flow. The correlation coefficient between actual and duplex-sonographically obtained flow was 0.975, mean percentage deviation being -18.1% (P less than 0.0001). The obvious scatter (margin of error -69.2 to +50%) is to be explained by the simulation closely imitating a real situation: the transducer was hand-held and tubes were placed in muscle or fat tissue. Accuracy was increased by multiple measurements, especially when taking into account only the maximal value of any series of measurements. Vessel diameter was easy to measure accurately (mean error less than 0.01% [-18.7 to +9.4%]). Repeated measurements of flow velocity had only a small scatter (coefficient of variance 0.064). In muscle or fat the Doppler signal was attenuated and the error the greater the deeper the level at which measurements were made. Low flow (common in patients with obstructive vascular disease) can also cause faulty results.
A new practically orientated phantom for evaluating Doppler Duplex equipment was developed and used to determine the possibilities and limits of color coded Doppler Sonography (Angiodynography) in the diagnosis of arterial occlusive disease of the lower extremity. The problems that may occur in quantifying flow in these arteries are analyzed. The influence of superimposed slices of various soft-tissues on flow quantification, on the spectral waves and on color coded visualisation of the arteries and the possibility to compensate those changes by the use of sonographic contrast agents are discussed.
In order to estimate morphologic changes of the femoral artery after an intermittent intraarterial infusion therapy duplex scanning was performed before therapy, immediately after a series of 26 (10 to 52) infusions, and 30 weeks after hospital discharge. Minimum and maximum values of internal and external vessel diameter and thickness of wall were estimated in the common femoral artery, superficial femoral artery, and deep femoral artery. The external diameter values and the thickness of wall increased significantly after therapy. After 30 weeks these values decreased but did not reach the initial values.
We are reporting on a 62 year old female patient with portal hypertension (splenomegaly, esophageal varicosis) without signs of liver cirrhosis, who was hospitalized for sclerotherapy of her esophageal varices. Physical examination showed up palmar- and plantar hyperkeratosis and Morbus Bowen or basalioma-like skin lesions++. Anamnestic evaluation revealed, that the patient's psoriasis had been treated with arsenic for many years. This kind of treatment may have induced intraluminal proliferation and obliteration of the portal vein's endothelium, thus being the etiologic factor responsible for noncirrhotic portal hypertension in this patient.
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