Venous and arterial anomalies of the lower extremities diagnosed by duplex scanning.

The complex embryologic development of the vascular system often results in a myriad of clinically relevant anomalies. It has been stated that the classic anatomic venous pattern in the lower extremity is found in only 16 percent of patients. Previous studies on this topic are limited to isolated venous dissections or phlebography that lack complete anatomic detail. The recent introduction of high resolution duplex scanners for the assessment of veins of the lower extremity provides a unique opportunity to determine the incidence of anatomic variation. The current prospective study was done to identify venous or arterial anomalies apparent during routine duplex scanning of the lower extremity performed to rule out deep venous thrombosis (DVT). Limbs that had evidence of acute or chronic extensive DVT were excluded. Of 1,600 consecutive extremity scans, 946 extremities (59 percent) had no evidence of DVT. Of these, there were 43 patients with 64 anomalies in 57 extremities. The mean age of the group was 53.4 years. There were 24 women (55.8 percent) and 19 men (44.2 percent). There were 59 (92.2 percent) venous and five (7.8 percent) arterial anomalies. Duplication of the superficial femoral vein was the most common anomaly noted. Duplication of the deep femoral and popliteal vein was also noted. Unilateral anomalies were more common than bilateral anomalies, namely 67.4 versus 32.6 percent, respectively. Pain and swelling, common complaints in the patients with an anomaly, were noted in 71.4 and 45.7 percent, respectively. The frequency of deep venous anomalies of the lower extremities may be less than previously reported. Knowledge concerning the incidence and distribution of venous anomalies may lead to improved assessment and treatment of venous disease.

Operative management of greater saphenous thrombophlebitis involving the saphenofemoral junction.

Forty-three consecutive patients with greater saphenous vein (GSV) thrombosis extending to the saphenofemoral junction (SFJ) were treated. Twenty-three patients had extension of thrombus into the common femoral vein (CFV). Twenty patients had thrombus extending to but not within the CFV. Symptoms, risk factors, and physical examination were not predictive of CFV thrombus extension. When compared with the operative record, duplex scans accurately located the extent of the thrombosis 100% of the time. Forty-one surgical procedures were performed. No patients had pulmonary emboli during the procedures. Thirty-seven patients were treated as outpatients or were discharged within 3 days of their surgical procedures. The two patients who did not undergo operative procedures in this series had complete occlusion of the CFV with extension into the external iliac vein. Thrombus within 3 cm of the SFJ is an indication for surgical intervention. Disconnection of the GSV from the CFV prevents extension of the thrombus, and a limited CFV thrombectomy can be performed when necessary. This is considerably more cost-effective than treatment with anticoagulation.

Experience with physiologic amputation using the CryoCare Extremity Stabilization System (CESS).

Five years of experience gained with the CryoCare Extremity Stabilization System (CESS) were evaluated in this study. Twenty-one patients underwent freezing amputation. Five patients died before undergoing surgical amputation. Symptomatic relief, control of odor, decreased demand on nursing staff, and appreciation of the family make this approach valuable even when long-term survival is not anticipated. Ten patients who underwent freezing amputation subsequently underwent surgical amputation and were discharged. Six patients underwent freezing and surgical amputation but died prior to discharge. The patients selected for the freezer application were deemed to be prohibitive operative risks because they were experiencing systemic toxicity from their ischemic limb and underlying diseases. Six patients demonstrated myoglobinuria prior to freezing which cleared with CESS. The physiologic amputation allowed stabilization of medical problems including cardiac arrhythmias, congestive heart failure, sepsis, renal failure, diabetes, and respiratory failure. Freezing of an ischemic extremity allows delay in amputation enabling physicians to achieve maximal medical stabilization. It permits symptomatic relief in patients whose long-term survival is not anticipated. Physiologic freezing amputation should be included in the repertoire of all surgeons.

Upper extremity venous duplex imaging.

Over 500 upper extremities have been imaged with the Duplex Scanner at the John J. Cranley Vascular laboratory. Venous anatomy and imaging techniques are presented. Reference points and zones for localizing abnormal findings are demonstrated. Abnormal venous pathology including case presentations of acute radial, basilic, cephalic, and axillary vein thrombosis are presented. Complications of subclavian and internal jugular vein catheterization are demonstrated. Soft tissue pathology including edema, lymphadenopathy, hematomas, cysts, and abscesses are visualized and differentiated. Duplex use for evaluation of aneurysm, pseudo aneurysm and graft surveillance has been increasing in frequency. Examples are demonstrated.

Lower extremity calf thrombosis: to treat or not to treat?

Seventy-five patients with isolated calf vein thrombi were prospectively monitored with sequential duplex scans at 3- to 4-day intervals. Twenty-four patients (32%) propagated and 11 of these 24 (46%) into the popliteal or larger veins of the thigh. Sex, age, obesity, trauma, estrogen use, malignancy, varicose veins, smoking, surgery, and activity level were not predictive for proximal propagation. Proximal soleal vein thrombi had the highest incidence in both propagating and non-propagating groups. Thrombus extent and bilateral involvement were not predictive of propagation. Five percent (4 of 75 patients) had highly probable ventilation perfusion scans as their initial indication for duplex scanning. Deep vein thrombosis isolated to the calf is not a benign problem. If anticoagulant therapy is contraindicated, the progress of the thrombus can be followed by duplex scanning.

Measurement of blood flow rates in the lower extremities with use of a nuclear magnetic resonance based instrument.

Direct, noninvasive measurement of pulsatile blood flow to the human extremity is now possible by means of a flow measurement instrument that is based on the principles of nuclear magnetic resonance. The instrument uses a physically independent calibration module as a primary calibration standard. Volumetric calibration of this module indicates that it is precise and accurate over the range of 0 to 100 ml/min. The calibration module is used, in turn, to calibrate an electromagnetic flow sensor that is incorporated into the instrumentation. The calibration module and the electromagnetic sensor were found to be linearly related over the range of 5 to 100 ml/min, with a regression correlation coefficient of 0.996. The calibrated electromagnetic flow sensor is used as a secondary standard for calibration of the nuclear magnetic resonance sensor. Blood flow measurements, obtained by use of this method, agree closely with those obtained by plethysmographic methods. They differ from the plethysmographic results in that magnetic resonance flows will distinguish between the at-rest blood flow in the normal extremity and the flows seen in the extremity (also at rest) with claudication. Based on the results obtained from studying a limited number of limbs with a high degree of ischemia, the method will not distinguish the limb with ischemia from the limb with claudication. Limitations of the method and refinements required to make the method clinically useful are discussed.

Superficial thrombophlebitis diagnosed by duplex scanning.

Since July 1982, this noninvasive vascular laboratory has performed 12,856 lower extermity venous duplex examinations. All cases of acute venous thrombosis have been categorized and entered into a computer data base. One thousand four hundred twelve examinations were positive for acute venous thrombosis. This report analyzes the laboratory's entire experience with superficial thrombophlebitis (SVT). One hundred eighty-six patients were diagnosed by duplex scanning to have SVT. Women outnumbered men 99 to 87. They were slightly older (average age 58.4 +/- 16.2 years) compared with the men (53.8 +/- 14.2 years). Men were more likely to have a complicated course of SVT (40% vs 22%; p less than 0.01). Complications included either radiographically documented pulmonary embolism or deep venous involvement. Fifty-seven (31%) patients had at least one complication of SVT. A series of predisposing factors was analyzed and six factors were associated with an increased risk of complications. They are bilateral SVT (p less than 0.01), age greater than 60 years (p less than 0.01), male sex (p less than 0.01), history of deep venous thrombosis (p less than 0.01), bed rest (p less than 0.02), and presence of infection (p less than 0.02). Location of thrombus within the greater saphenous vein (35%) was most likely to be associated with complications. Isolated varicosities (8%) were least likely to be associated with complications. Duplex scanning identifies a significant number of complications of patients with SVT and should be obtained in cases of saphenous vein involvement or in the presence of associated risk factors.

Analysis of 1084 consecutive lower extremities involved with acute venous thrombosis diagnosed by duplex scanning.

A retrospective analysis of 8658 consecutive lower extremity venous duplex scans performed between the years 1982 to 1988 revealed 953 patients with involvement of 1084 extremities with acute deep or superficial thrombi. Records of patients with acute thrombi were then evaluated for the incidence, location, and patterns of distribution. There were 485 women (50.9%) and 468 men (49.1%), with a mean age of 62.9 +/- 16.7 years and 58.8 +/- 15.2 years, respectively. There were 371 right-sided thrombi (180 women and 191 men), 451 left-sided thrombi (235 women and 216 men), and 131 (70 women and 61 men) patients with thrombi in both lower extremities. Women were found to be uniformly older, and the left leg was found to be involved more frequently (p less than 0.05). The overall distribution of the 3169 veins involved with acute thrombi in decreasing order were: popliteal, 16.1%; superficial femoral, 15.0%; posterior tibial, 13.4%; common femoral, 13.2%; greater saphenous, 9.9%; soleal, 9.1%; peroneal, 7.2%; deep femoral, 6.6%; lesser saphenous, 5.7%; anterior tibial, 2.0%; varicosities, 1.6%; and perforating, 0.3%. A different rank order was found in analysis of single thrombus patterns as follows: greater saphenous, 27.5%; soleal, 20.1%; lesser saphenous, 13.4%; varicosities, 8.8%; popliteal, 8.1%; posterior tibial, 9.1%; common femoral, 3.5%; superficial femoral, 4.9%; peroneal, 2.8%; deep femoral, 1.0%; anterior tibial, 0.3%; and perforating, 0.3%. In patients with multiple and bilateral thrombi there was a large number of unique patterns of thrombosis. Locations, patterns, and frequency of acute venous thrombi vary with age, sex, and leg involved. Patterns and statistical analyses of pertinent observations were performed.

Upper extremity venous thrombosis diagnosed by duplex scanning.

The incidence of axillary-subclavian venous thrombosis continues to rise, while reports of noninvasive methods to diagnose this condition have been sparse. A review of the records of 693 consecutive upper extremity duplex scans was performed, and a diagnosis of acute venous thrombosis was made in 123 of these patients. Of these, 85 involved the axillary or subclavian vein. Use of a central venous catheter was the most common risk factor for axillary-subclavian venous thrombosis. Within this group, 8% had a pulmonary embolism, of which 25% were fatal. Follow-up of patients with axillary-subclavian venous thrombosis at a mean of 2 years revealed that 49% of these patients had died. Of the remaining patients, more than one third had evidence of the post-thrombotic syndrome. Duplex scanning of the venous system provides a safe, reliable, and repeatable method of evaluating and following patients with suspected venous thrombosis of the upper extremity.