[Laser-Doppler technique in diseases of peripheral blood vessels].
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Diabetic Angiopathies↗
Biomedical subjects
A Bollinger
Publications and source records attributed to A Bollinger.
[Livedo racemosa, skin necrosis at the basal toe joint].
An 81 year old male patient treated by sulfonylurea and diet was known to have type II diabetes for three years. Because of pulmonary embolism phenprocoumon had been administered for four months. Painful livedo racemosa developed acutely on both lateral sides of the feet and the left knee. A necrosis of the skin over the base of the left small toe developed within a few days. On the basis of the clinical picture cholesterol-embolism was diagnosed. Since anticoagulation is known to promote cholesterol-embolism it was discontinued. Prostaglandin E1 infusions into both legs were administered. Within 3 months the cutaneous lesions healed completely.
Aged↗
Cutaneous and coronary flow reserve in patients with microvascular angina.
Microvascular angina is characterized by exercise-induced angina in patients with normal coronary arteries and reduced coronary flow reserve. Recently, a generalized disorder of abnormal vascular reactivity in microvascular angina has been postulated. Therefore, coronary flow reserve was determined by the coronary sinus thermodilution technique and compared with the cutaneous flux ratio in 6 control subjects (group 1) and 12 patients with microvascular angina (group 2). Coronary flow reserve was calculated from maximal coronary flow after 0.5 mg/kg of dipyridamole divided by flow at rest. Cutaneous flow ratio was estimated by laser Doppler fluxmetry (right forearm) before and after 4 min of suprasystolic blood pressure occlusion. Coronary flow at rest was identical in the two groups, but after maximal vasodilation with dipyridamole, coronary flow was higher in group 1 than in group 2 (p less than 0.05). Coronary flow reserve differed significantly between the two groups (2.9 in group 1 and 1.3 in group 2; p less than 0.001). Cutaneous Doppler flux at rest was higher in group 1 than in group 2 (p less than 0.05). However, the hyperemic response was identical in both groups. It is concluded that the cutaneous flux ratio in patients with microvascular angina is not impaired. Local peripheral vasomotor tone appears to be increased in patients with microvascular angina because cutaneous flow at rest is reduced. Thus, a generalized disorder of abnormal vascular reactivity cannot be confirmed in patients with microvascular angina.
Adult↗
Swollen lower extremity: role of MR imaging.
The authors assessed the use of magnetic resonance imaging in differentiating lymphedema, phlebedema, and lipedema of the lower limb. They examined 14 patients: five with lipedema, five with lymphedema, and four with phlebedema. T1- and T2-weighted transaxial sequences were performed before administration of gadolinium tetraazacyclododecane-tetraacetic acid (DOTA) and T1-weighted spin-echo sequences were performed after administration of Gd-DOTA in each patient. Images of patients with lipedema showed homogeneously enlarged subcutaneous layers, with no increase in signal intensity at T2-weighted imaging or after Gd-DOTA administration. Patients with phlebedema had areas containing increased amounts of fluid within muscle and subcutaneous fat. In lymphedema, a honeycomb pattern above the fascia between muscle and subcutis was observed, with a marked increase in signal intensity at T2-weighted imaging. After Gd-DOTA administration, there was only a slight increase in signal intensity in the subcutis in lymphedema and phlebedema and a moderate increase in signal intensity in muscle in phlebedema.
Adolescent↗
Pressure of lymphatic capillaries in human skin.
The network of lymphatic capillaries of the human skin was depicted at the distal part of the tibial plateau by fluorescence microlymphography (fluorescein isothiocyanate-dextran 150,000). Intralymphatic pressure was determined in 28 lymphatic capillaries of 21 healthy volunteers (mean diameter 56.0 +/- 10.0 microns) by a servo-nulling pressure system. It averaged 4.0 +/- 4.5 mmHg (range: -6.8 to +10.7 mmHg). These are the first measurements of pressure in the initial lymphatics of human skin and form a basis with which to compare measurements made in patients with different forms of edema.
Adult↗
[Double-blind study of the effect of dipyridamole in patients with intermittent claudication].
32 patients (mean age 65 years, range 51-75 years) were included in this controlled, double blind study to evaluate the effect of dipyridamole in patients with intermittent claudication. Following a run-in phase of one month, 15 patients received 400 mg dipyridamole per day and 17 patients placebo. Patient characteristics (risk factors, age, clinical and apparative tests) of both groups did not differ significantly before and during the study period. Mean pain free und absolute walking distance on the treadmill (3.2 km/h, 12.5 degrees gradient) increased significantly in both groups during study period (p < 0.001 and p < 0.01). Explanations are more intensive physical activity and increasing adaptation to treadmill exercise. However, dipyridamole did not induce a significantly longer walking distance in comparison with placebo. The working hypothesis that the drug with inhibiting properties of thrombocyte function prolongs walking distance in intermittent claudication, could not be confirmed.
Aged↗
Microangiopathy in Ehlers-Danlos syndrome type IV.
In two patients with Ehlers-Danlos syndrome type IV, an autosomal dominant disorder characterized by fragility of large vessels, excessive bruising, and deficiency in type III collagen, capillary microscopy was performed at the nailfold. Indocyanine green and Na-fluorescein were used as fluorescent tracers. Both patients exhibited microangiopathy of the skin capillaries with microbleedings, presence of microaneurysms and increased transcapillary diffusion. Microvascular involvement appears to be an additional manifestation of the syndrome.
Adult↗
Laser Doppler technique for the measurement of digital and segmental systolic blood pressure.
A technique is described for measuring digital and segmental systolic blood pressure by laser Doppler fluxmetry. A transparent plastic capsule contains the small sphygmomanometer cuff connected to a Statham manometer. It has a hole for positioning the probe at the very tips of fingers or toes. An advantage of this method over the conventional strain-gauge technique is that it is better suited for determinations at short digits where it is difficult to fix a strain-gauge. Moreover, it allows consecutive pressure and flux measurements at almost identical distal sites without moving the probe. The correlation between the values obtained by the conventional and laser Doppler procedures are excellent. Systolic pressures were determined on 14 extremities of 7 healthy controls and on 20 extremities of 14 patients with intermittent claudication due to peripheral arterial occlusive disease. Measuring sites were the upper arm, forearm, index finger, ankle and big toe. The values agree well with those obtained earlier by the strain-gauge technique.
Aged↗
Percutaneous transluminal angioplasty (PTA) of the deep femoral artery.
Between 1979 and 1988 43 percutaneous transluminal angioplasties (PTA) of the deep femoral artery were performed for treatment of severe claudication (n = 15) or for limb salvage (n = 28). Ateriographically, all patients had a long occlusion of the superficial femoral artery. Additional PTA of significant obstructions in the iliac and common femoral artery were performed in 6 patients of each group. Technical success was achieved in 41 of the 43 procedures (95%). Early clinical success was 60% for claudicants and 68% for patients with limb threatening ischemia. Success rates tended to be higher if additional PTA of the inflow tract was performed (75% versus 61%, n.s.). Patient with a good distal outflow benefited more frequently from PTA if they were treated for limb salvage (p less than 0.05). Within a follow-up period up to 24 months (mean 18.0 months) 5 patients died and one late failure occurred. Life table analysis lasting success in patients dilated for limb salvage, whereas success rate decreased to 48% in claudicants. PTA of the deep femoral artery is a less invasive and efficient treatment particularly for patients with limb threatening ischemia, an appropriate obstruction morphology provided.
Aged↗
[The status of thrombolysis in treatment of peripheral arterial occlusive diseases].
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Angiography↗
[Aneurysm of the abdominal aorta. Diagnosis and indications for therapy].
Atherosclerotic abdominal aortic aneurysms are found in about 4% of all men aged over 65 years. The most severe complication of the abdominal aortic aneurysm is rupture. The probability of rupture depends upon the diameter of the aneurysm. The chance of rupture is 30% within 2 years in aneurysms with a maximum diameter of more than 5 cm. Preoperative evaluation includes clinical examination and abdominal ultrasonography. Depending on the results, aortography and/or computed tomography are required. When the diameter is less than 5 cm in an asymptomatic patient, conservative management is indicated provided that clinical tests and ultrasonography are performed on a regular basis. The mean increase of diameter varies between 0.2 and 0.4 cm/year. All aneurysms with a diameter of more than 5 cm should be treated by implantation of a dacron graft. Symptomatic aneurysms should, independently of the diameter, be considered an emergency situation and resected immediately. Patients with ruptured aneurysms have a poor prognosis; only 40-60% of these patients reach the hospital and approximately 50% of them die despite immediate surgery. A special subgroup is the so called inflammatory abdominal aortic aneurysm. Characteristic findings of this entity are increased wall thickness and retroperitoneal fibrosis. The indications for resection are the same as for the atherosclerotic aneurysm. If management is conservative, treatment with corticosteroids is useful.
Adrenal Cortex Hormones↗
[Microangiopathy in chronic venous insufficiency].
Skin in the medial malleolar region was examined in 15 patients with moderately severe venous insufficiency (9 women, 6 men; mean age 57 [35-76] years), using intravital fluorescence microscopy, transcutaneous pO2 measurement and laser Doppler flowmetry. The findings were compared with those in a healthy control group (8 women, 7 men; mean age 53 [35-73] years). The arteriolar vasoconstriction response was tested by comparing laser Doppler flowmetry readings in the recumbent and sitting positions. Transcutaneous pO2 was likewise measured in both positions. Capillary morphology and microangiodynamics were investigated before and after injection of Na-fluorescein. The microangiopathy of moderately severe venous insufficiency was characterised fluorescence microscopically by greatly dilated, elongated and winding (glomerulus-like) capillaries, and by an increase in the pericapillary leakage diameter (halo). However, the vasoconstrictive response to change in posture remained largely intact, and there was little alteration in the spontaneous rhythmic flow waves. In contrast, flow in the recumbent position was significantly increased (P less than 0.001), since laser Doppler flowmetry also measures the flow in deeper (1-6 mm), non-nutrient skin vessels. In spite of a normal capillary count, the mean transcutaneous pO2 was reduced, in keeping with the microangiopathy observed in the superficial nutrient capillaries. These pronounced morphological and dynamic changes explain the development of trophic lesions.
Adult↗
[Dermatomyositis--diagnostic value of capillary microscopy].
The results of conventional capillary microscopy and fluorescence videomicroscopy are described in 7 patients with well established dermatomyositis (mean age 34.3 +/- 19 years, mean duration of the illness 25.7 +/- 26.9 months). All patients showed marked microangiopathy characterized by avascular fields, increased capillary tortuosity and enlargement, and enhanced transcapillary diffusion. The capillary microscopy pattern was not specific for dermatomyositis. Nevertheless, capillary microscopy plays an important role in the differential diagnosis of this condition. It remains unclear how sensitive this method is in the early detection of dermatomyositis.
Adult↗
Evaluation of flux motion in man by the laser Doppler technique.
Analysis of flux motion by the laser Doppler technique in the forefoot of healthy controls and patients with peripheral arterial occlusive disease was performed by establishing computerized frequency histograms. It was found that the low frequency components (1-10 cycles/min) are caused by local vasomotion. The prevalence of high frequency flux waves (15-25 cycles/min) is significantly increased in peripheral ischemia compared to normal conditions. After successful reopening of large arteries by angioplasty the prevalence decreases (p less than 0.001). Preliminary results indicate that these high frequency rhythmic fluctuations might by induced by respiration.
Arterial Occlusive Diseases↗
Intravital detection of skin capillary aneurysms by videomicroscopy with indocyanine green in patients with progressive systemic sclerosis and related disorders.
Conventional capillaroscopy and infrared fluorescence videomicroscopy with indocyanine green were performed at the nailfold in 12 healthy controls and 38 patients with microangiopathy due to systemic sclerosis or related disorders. Saccular aneurysms featuring head and neck (type 1) and aneurysmatic enlargements (type 2) were defined. Microaneurysms were located at the apex or near the apex of capillary loops and were significantly more common in patients than in controls (p less than 0.02 for type 1 and p less than 0.001 for type 2). Combination of the two lesions was found only in patients and appears to be a valuable new diagnostic sign for the presence of microangiopathy. In comparison with conventional capillaroscopy, about twice as many microaneurysms were detected by videomicroscopy with indocyanine green coupling almost completely to plasma proteins. The new technique allows visualization of capillary aneurysms even when filled only by plasma.
Adult↗
[Intermittent venous claudication].
Intermittent venous claudication develops mostly in young patients after iliac vein thrombosis and subsides promptly in the recumbent position. Plethysmographic assessment of calf volume during treadmill work permits objective diagnosis of the phenomenon remaining frequently unrecognized.
Adult↗
[Microangiopathies in chronic venous insufficiency (CVI)].
The degree of cutaneous microangiopathy at the medial ankle correlates with the severity of chronic venous insufficiency, most probably it is the trigger factor for development of trophic skin lesions. Using intravital fluorescence videomicroscopy, microlymphography, transcutaneous oxygen tension measurement and laser Doppler flowmetry, the microangiopathy is characterized by morphological alterations of blood and lymph capillaries and by dynamic changes (decreased transcutaneous oxygen tension reflecting microvascular ischemia, increased skin perfusion). Microangiopathy in patients with chronic venous insufficiency is recognized by the presence of dilated, elongated and tortuous (glomerulus-like) capillaries and by an increase in diameter of the pericapillary space (halo) filled by Na-fluorescein. In severe CVI a reduction of the capillary number can be observed, probably as a result of previous capillary thrombosis. Lymphatic drainage is disturbed and lymph capillaries are obliterated in part. Laser Doppler flowmetry, which detects flux in deeper, non-nutrient skin vessels, shows increased blood flow. However, the postural vasoconstrictive response remains intact and there is little alteration in the spontaneous rhythmic flux waves. In contrast to deeper skin flux transcutaneous oxygen tension is reduced, in keeping with the microangiopathy observed in the superficial nutrient capillaries. These pronounced morphological and dynamic changes explain the development of trophic skin lesions.
Blood Gas Monitoring, Transcutaneous↗