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S M Schellong

Publications and source records attributed to S M Schellong.

29 records · Page 2Linked to original sources
PubMed1999

Popliteal entrapment syndrome: non-invasive diagnosis and complete recovery after surgery in an 11-year-old boy.

We present an unusual case of popliteal entrapment syndrome type I in an 11-year-old boy. Presenting symptoms were exercise-related pain and pallor in his left lower leg. The diagnosis of popliteal entrapment syndrome was established by acral plethysmography, colour-coded Doppler sonography and MRI. After myotomy of the gastrocnemius muscle the symptoms resolved completely. Post-operative duplex scan showed normal blood flow, even in plantar flexion of the foot.

Arterial Occlusive Diseases↗
PubMed1999

[Special aspects of therapy of non-atherosclerotic vascular diseases].

The long term course of thromboangiitis obliterans as well as frequency and extent of major or minor limb amputations depend almost exclusively on the smoking behaviour of the patients. Superficial phlebitis accompanying an acute relapse responds well to high-dose aspirin or NSAIDs. Critical limb ischemia is treated by intra-arterial or intravenous prostaglandins (Alprostadil, Iloprost). Lokal measures for finger, toe, or foot gangrene do not differ from comparable sequelae of atherosclerotic vascular disease. Revascularisation procedures (angioplasty, surgery) have a high rate of technical failure and are indicated only in rare atypical situations. Corticosteroids are the therapy of choice for both vasculitides of large muscular arteries, i.e. temporal arteritis (M. Horton) and Takayasu arteritis. Combination therapy is restricted to steroid refractory disease; while this is the exception in temporal arteritis, it occurs in up to 50% of patients with Takayasu arteritis. Critical limb ischemia due to giant cell arteritis may persist even if the inflammatory activity of the disease is well controlled. Revascularisation procedures in Takayasu arteritis may have good results; as with all other therapeutic measures in this disease, they should be provided by specialized centers. Treatment of Raynaud's phenomenon requires patient evaluation for signs or symptoms of an underlying disease, i.e. some kind of connective tissue disease. Strength and frequency of attacks depend on a number of different factors (triggers) which in a given patient may not be completely understood. Exposition prophylaxis for known triggers and vasodilator drugs are the main therapeutic measures in Raynaud's phenomenon. Careful documentation of disease activity provided, non-classical remedies (behavioural psychotherapy, acupuncture) may be attempted.

Arterial Occlusive Diseases↗
PubMed1999

Bed rest in deep vein thrombosis and the incidence of scintigraphic pulmonary embolism.

In several countries of central Europe, patients with acute proximal deep vein thrombosis (DVT) are treated not only by anticoagulation and compression therapy but additionally by strict bed rest for 6-8 days. Until now the theoretical assumption that bed rest substantially reduces the incidence of pulmonary embolism has not been subjected to empirical verification. Patients with acute proximal DVT proven by ultrasonography were randomly assigned to strict bed rest for 8 days (treatment group) or to stay mobilised (control group). In both groups, basic treatment consisted in anticoagulation by subcutaneous low molecular weight heparin/vitamin-K-antagonist and compression therapy. The incidence of pulmonary embolism was assessed by serial ventilation/perfusion SPECT on day 1 and days 8-10. Of the 309 patients with proximal DVT considered for inclusion, 180 were excluded according to the study protocol, and 3 did not give informed consent. One hundred and twenty-six patients were randomly assigned to observe bed rest (n = 62) or to keep mobilised (n = 64). Four patients refused follow-up lung scan. A new lung perfusion defect was detected in 10/59 patients in the treatment group compared to 14/63 patients in the control group (one-sided p-value = 0.25; power 0.8). Bed rest as an additional measure in the treatment of DVT is not able to substantially reduce the incidence of scintigraphically detectable pulmonary embolism. The discomfort and costs associated with the prescription of bed rest in DVT are obviously inappropriate.

Adult↗
PubMed1998

[Value of color-coded duplex ultrasound in interstitial laser therapy of hemangiomas and vascular malformations].

BACKGROUND: The diagnosis of hemangiomas and vascular malformations prior to interstitial laser therapy is principally based on clinical and B-mode ultrasonographic examination. Color-coded duplex ultrasonography provides additional information about the vascularization of these tumors. The aim of this study is to evaluate the benefit of this information for the diagnosis and treatment of hemangiomas. PATIENTS AND METHODS: We examined 30 patients suffering from hemangiomas of various sizes and locations. A preliminary treatment plan was developed on the basis of B-mode ultrasonographic examination. This preliminary plan was either verified or changed after obtaining color-coded duplex ultrasonographic studies. RESULTS: In comparison to B-mode ultrasonography, color-coded duplex ultrasonography allows clinically relevant classification of hemangiomas on the basis of their vascularization (no flow, palpation-induced flow, predominantly venous flow, predominantly arterial flow). In 53% of the cases, the preliminary therapeutic plan was modified partially or wholly on the basis of this additional information (new diagnosis, change in the planned surgical approach, and favoring other initial diagnostic and therapeutic options over laser therapy). CONCLUSION: Color-coded duplex ultrasonography provides important additional information compared to B-mode ultrasonography and decisively influences hemangioma therapy. This imaging technique should be recommended for routine preoperative application in hemangiomas.

Adolescent↗
PubMed1998

Prostaglandin E1 in peripheral vascular disease: a PET study of muscular blood flow.

BACKGROUND: Increase of blood flow in the ischaemic leg is believed to represent the main action of prostaglandin E1 (PGE1) in the therapy of peripheral vascular disease (PVD). There is no reliable data in man concerning the amount of increase in muscular blood flow (MBF) of the calf, and the difference between intra-arterial and intravenous application. PATIENTS AND METHODS: We conducted a positron emission tomography (PET) study of MBF with 15O-water as flow tracer. Fifteen patients with PVD and three healthy volunteers were given 5 micrograms PGE1 intra-arterially over 50 min; PET scans were taken at 0, 25 and 50 min. Additionally, eight of the patients were investigated during an intravenous infusion of 40 micrograms PGE1 over 120 min; PET scans were taken at 0, 30, 60 and 120 min. RESULTS: Increase of muscular blood flow by intra-arterial PGE1 averaged 80%. A steal phenomenon was not observed. The amount of flow enhancement depended on whether or not the femoral artery was patent. During intravenous PGE1, muscular blood flow remained unchanged. CONCLUSIONS: In man, the pharmacodynamic profile of intra-arterial PGE1 differs clearly from intravenous PGE1. The flow-enhancing property is lost during metabolization in the lung. Since no difference exists between the therapeutic efficacy of intraarterial and intravenous PGE1, the impact on muscular blood flow is not as important as suggested previously.

Adult↗
PubMed1998

[Pathophysiology and clinical aspects of ischemia-reperfusion damage to skeletal muscles].

Ischemia/reperfusion-injury of skeletal muscle--pathophysiology and clinical implications. Ischemia and reperfusion of skeletal muscle occurs in acute vascular occlusion and revascularisation, in elective vascular surgery, in orthopedic surgery by means of a tourniquet, and in transplantation of muscle-containing cutaneous flaps. The ischemia sets up a cascade of events, which fully develops not prior to the moment of reperfusion. The ischemia-reperfusion-cascade is comparable to an overwhelming inflammatory reaction out of control. Depending on the duration of ischemia it prompts an injury for the muscle itself, and in some cases for the whole body. The present review discusses the main mechanisms of ischemia/reperfusion-injury in terms of cellular metabolism, endothelial function, cytokine release, and leucocyte function. Release of toxic oxygen radicals by activated leucocytes plays the pivotal role in this reaction. In addition, the clinical manifestations of ischemia/reperfusion will be reviewed as well as some of the means proposed to control this harmful reaction.

Animals↗
PubMed1997

Dose-related effect of intravenous L-arginine on muscular blood flow of the calf in patients with peripheral vascular disease: a H215O positron emission tomography study.

1. Endothelium-derived nitric oxide (NO) contributes to the regulation of vascular tone and blood pressure. Infusion of L-arginine produces systemic vasodilatation via stimulation of endogenous NO formation. Vasodilatation is accompanied by an increase in peripheral arterial blood flow. However, it is not known whether capillary nutritive blood flow increases as well. The time course and dose-response pattern of this effect remain to be elucidated. 2. Two groups of ten patients with peripheral vascular disease (PVD) received an intravenous infusion of 8 g or 30 g of L-arginine over a period of 40 min. Blood pressure and heart rate were monitored non-invasively. Muscular blood flow (MBF) of the calf was determined at 0, 20, 40, 60, 80 min by positron emission tomography with H215O as flow tracer. Plasma L-arginine and cyclic GMP (cGMP) levels were determined at the same time points. 3. L-arginine induced a dose-related decrease in blood pressure during the infusion period. MBF and plasma cGMP levels during and after the infusion of 8 g of L-arginine did not change significantly. In the patients receiving 30 g of L-arginine, MBF was enhanced significantly from 1.56 +/- 0.14 to 2.09 +/- 0.21 ml min-1 100 ml-1 at 40 min and 2.23 +/- 0.15 ml min-1 100 ml-1 after 80 min (+43.0%). The increase in MBF was paralleled by an increase in plasma cGMP from 4789.8 +/- 392.2 nmol/l at baseline to 9223.2 +/- 1233.6 nmol/l at 40 min. 4. We conclude that intravenous L-arginine enhances nutritive capillary MBF in patients with PVD via the NO-cGMP pathway in a dose-related manner. This effect might be therapeutically beneficial in patients with PVD.

Aged↗
PubMed1997

Classification of Sneddon's syndrome.

BACKGROUND: The combination of generalized broken ("racemose") livedo and cerebrovascular accidents is referred to as "Sneddon's syndrome". Although several pathogenetic factors have been suggested the aetiology of Sneddon's syndrome is unknown. Furthermore, considerable variability of patient characteristics gives rise to the question whether "Sneddon's syndrome" denotes a homogeneous disease entity at all. We hypothesized that the diagnosis "Sneddon's syndrome" can be broken down into different subgroups according to possible aetiologic factors. PATIENTS AND METHODS: Thirty-two patients with the combination of generalized broken livedo and cerebrovascular accidents were evaluated by clinical examination, routine diagnostic procedures, MRI of the brain, echocardiography, vascular ultrasound, immunologic and haemostaseologic testing. Patient groups were formed, depending on (1) whether or not an additional feature with a possibly aetiologic role for Sneddon's syndrome was present, and (2) which kind of feature it was. RESULTS: In 16 out of 32 patients, diagnostic features with an implication for the pathogenesis of Sneddon's syndrome could be identified. An autoimmune disorder was diagnosed in six patients. A thrombophilic state was detected in six patients. Three patients had preexisting atherosclerosis. One patient suffered from an embolizing atrial myxoma. Extent and kind of cerebral pathology differed between patient groups as did the kind of cardiac involvement. CONCLUSION: Sneddon's syndrome is not a homogeneous disease entity. Patients should be classified as "primary Sneddon's syndrome" if no aetiologic factor can be detected. On clinical grounds, this from differs from several varieties of "secondary Sneddon's syndrome" which occurs mainly as part of an autoimmune disorder or in a thrombophilic state.

Adult↗
PubMed1994

Intestinal type of thromboangiitis obliterans (Buerger's disease).

Thromboangiitis obliterans (TAO) is a recurrent, inflammatory, segmental occlusive disease of distal limb arteries which may involve veins as well. Young smokers are predisposed to TAO. The intestinal vessels are rarely affected. We report the clinical, angiographic and histologic findings of a 23-year-old smoker with extended thrombophlebitis who developed severe abdominal angina and liver hypoxia due to occlusion of the coeliac artery and subtotal occlusion of the superior mesenteric artery. Two surgical bypassing procedures were followed by early graft occlusion. Subsequently, a plastic patch of the superior mesenteric artery and an aortohepatic bypass were performed. The literature since 1945 pertinent to intestinal TAO is reviewed.

Adult↗