Mobilization of fluids in large volumetric reductions during intensive treatment of leg lymphedema.

AIM: The aim of the current study was to evaluate fluid mobilization during the intensive treatment of leg lymphedema. METHODS: The mobilization of intracellular and extracellular fluids in the lower and upper extremities and trunk was evaluated with the intensive treatment of leg lymphedema in a prospective study. Mobilization of fluids was assessed by bioelectrical impedance using the InBody S10 device in ten patients with leg lymphedema, regardless of the cause. Treatment consisted of six to eight hours per day of Manual Lymphatic Therapy (Godoy & Godoy technique), Mechanical Lymphatic Therapy (RAGodoy device®) and a non-elastic cotton-polyester stocking. RESULTS AND CONCLUSION: A significant reduction in total water was observed for the lymphedematous limb, but with an increase in intracellular water of from 59% to 61%. Additionally, total water increases were observed in the limbs without lymphedema and in the trunk. There was an increase in total intracellular water of the extremities and trunk, but without any change in the extracellular water. In high-volume reductions during lymphedema treatment, fluids are displaced from the lymphedematous limb to extremities without lymphedema and to the trunk.

Progression of reflux patterns in saphenous veins of women with chronic venous valvular insufficiency.

BACKGROUND: Venous ultrasonography identifies reflux patterns of the great and small saphenous veins (GSV, SSV), allowing evaluation of lower extremities for treatment planning and patient follow-up. OBJECTIVE: To determine progression of saphenous vein reflux patterns in women with primary venous valvular insufficiency. METHODS: Venous ultrasonography was performed in the extremities of 92 women, 43 ± 12 (23-77) years old, CEAP (clinical, aetiological, anatomical and pathological elements) clinical classes C1-C2. Two examinations were performed 33 ± 19 (8-89) months apart in patients without saphenous vein treatment. GSV and SSV reflux patterns were classified as segmental, multisegmental, distal, proximal, diffuse and normal. Prevalence was determined for each examination, separately for right and left extremities, and jointly. Prevalence was compared using χ2 statistics. RESULTS: Reflux prevalence was higher for the GSV, 89% (164/184) and 88% (n = 162), than for the SSV, 24% (n = 45) and 30% (n = 56), respectively for first and second examinations (P < 0.001). Reflux pattern prevalence was not significantly different in the right and left extremities (1.0 > P > 0.14). Most prevalent patterns were (a) GSV segmental reflux initially, 41% (76/184), decreasing to 28% (52/184) (P = 0.009), and (b) GSV multisegmental reflux at the second examination, increasing from 26% (48/184) to 40% (73/184) (P = 0.006). Prevalence of other GSV or SSV reflux patterns did not change significantly (0.88 > P > 0.19). CONCLUSIONS: We documented early findings and venous reflux progression in a specific population of women with varicose veins, reticular veins and telangiectasias. GSV segmental reflux was most prevalent initially, progressing to GSV multisegmental reflux.

Assessment of venous thrombus time of progression by gray-scale median analysis.

AIM: To determine if gray-scale median (GSM) analysis could differentiate acute and recent deep venous thrombosis (DVT). METHODS: Patients submitted to vascular ultrasound examination of lower extremities due to suspected DVT were evaluated. Patients with acute or recent femoropopliteal DVT were included, whereas those without DVT, with chronic or isolated calf DVT were excluded. Time of onset of DVT symptoms was recorded. A transverse image of the thrombosed vein and adjacent artery was obtained. Two sonographers determined a subjective impression of thrombus time of progression and classified it as acute or recent. Thrombus GSM was calculated with a software. ROC curve was used to determine GSM cut-off points. Fischer's exact and Student´s t tests were also used. P<0.05 indicated statistical significance. RESULTS: 128 veins of 63 extremities were studied. Thrombus GSM correlated with time of onset of DVT symptoms (P=0.005) and with subjective evaluation of thrombus time of progression (P<0.001). When DVT symptoms had begun up to two weeks before and thrombus was classified as acute, GSM was lower. Area under ROC curve for thrombus GSM was 0.76 (P<0.001). GSM 17.90, 23.03, and 40.02 cut-off points differentiated between acute and recent thrombi with 35.59% sensitivity and 91.30% specificity, 59.32% sensitivity and 84.06% specificity, 91.53% sensitivity and 31.88% specificity, respectively. CONCLUSION: GSM was a reliable tool for objectively differentiating acute and recent DVT in most thrombus images. GSM 17.90 and 40.02 cut-off points showed high specificity and high sensitivity, respectively, for acute and recent DVT differentiation. In 17.90 to 40.02 interval, GSM cut-off point that best distinguished acute from recent DVT was 23.03.

Does the number of pregnancies affect patterns of great saphenous vein reflux in women with varicose veins?

OBJECTIVES: Impact of pregnancies on great saphenous vein (GSV) reflux patterns deserves clarification. Which GSV segment is most affected? Is the saphenofemoral junction (SFJ) involved? METHODS: Colour-flow duplex ultrasonography was performed in 583 women extremities with primary varicose veins (clinical, aetiological, anatomical and pathological elements [CEAP C2]), without oedema, skin changes or ulcer. Women with previous thrombosis or varicose surgery were excluded. GSV reflux sources and drainage points were located at SFJ, thigh, knee and calf. Prevalence of most proximal reflux source was noted as a function of 0, 1, 2, 3 and 4 or more pregnancies. chi(2) statistics was employed. RESULTS: Prevalence of GSV reflux was not dependent on 0, 1, 2, 3 or >or=4 pregnancies: 75%, 69%, 79%, 70% and 76% for right leg (P = 0.79) and 78%, 81%, 82%, 79% and 73% for left leg (P = 0.87), respectively. Prevalence of SFJ reflux and GSV reflux, starting at the thigh, knee or calf, was similar and showed no tendencies to increase with number of pregnancies. CONCLUSIONS: Number of pregnancies did not influence GSV reflux patterns in women with primary varicose veins.

Incidence of side effects using carbon dioxide-oxygen foam for chemical ablation of superficial veins of the lower extremity.

OBJECTIVES: To determine the incidence of side effects following treatment of varicose veins with carbon dioxide-oxygen (CO(2)/O(2)) foam sclerotherapy, and to compare results with historical controls using CO(2)- or air-based foams. DESIGN: Cohort study with prospective data collection, private clinic setting. PATIENTS: The patient population consisted of one hundred patients, 95% women, age 52 SD 13 years-old, CEAP class C(2)EpAsPr. METHODS: Patients underwent ultrasound-guided foam sclerotherapy following thermal ablation of saphenous trunks; 1-3% polidocanol and 70%CO(2)-30%O(2) gas were mixed in a 1:4 proportion. Volume injected averaged 22 SD 11 (range: 2-46) mL. Vital signs were monitored for 1 h; side effects were recorded up to 24 h post treatment. Incidence of side effects was compared to CO(2)- and air-based foam data. RESULTS: Heart rate decreased from 73 SD 11 at the start to 68 SD 9 bpm (p < 0.001, paired t-test) following the procedure. Systolic and diastolic pressures, 127/75 SD 18/14 mmHg, respiratory rate, 15 SD 4 rpm and pO(2), 98 SD 2%, did not change significantly. Itching (7) or leg pain (24) reporting was similar to that for air-based foam (p = NS). Lack of reported chest tightness and/or dry cough was superior to our previous data with CO(2) or air foam (p < 0.05). Reporting of dizziness (1) was less than that for air-based foam (p = 0.002). The incidence of visual disturbance (2%), was comparable with that for CO(2) (3%) or air (8%) foam, but too few cases were available for meaningful statistical analysis. CONCLUSIONS: Foam sclerotherapy using CO(2)/O(2) foam was well tolerated by patients and resulted in fewer side effects than similar treatment using air foams.

Does repeat duplex ultrasound for lower extremity deep vein thrombosis influence patient management?

The clinical significance of lower extremity deep vein thrombus (DVT) propagation in the setting of anticoagulation therapy remains unclear. The purpose of this study is to compare results of thrombus outcome found with repeat duplex ultrasonography to the incidence of pulmonary embolism and mortality. During a recent 18-month period, 457 patients were diagnosed with lower extremity DVT with duplex ultrasonography and their data were retrospectively analyzed. Repeat examinations were available for review in 118 patients (51 men, 67 women). Results of repeat duplex exams were divided into 4 groups: resolved, improved, unchanged, or extended proximally. All patients received heparin and warfarin therapy. Ventilation-perfusion (V/ Q) scans were obtained only for signs and symptoms of pulmonary embolism (n=30). Mortality, the prevalence of high-probability V/ Q scans, frequency of intracaval filter insertion, gender, mean age, mean prothrombin time (PT), mean partial thromboplastin time (PTT), mean number of repeat ultrasounds per patient, and mean time over which the repeat ultrasounds took place were compared among the 4 groups. Patients who had proximal extension of DVT (19%) on repeat duplex ultrasound had an increased prevalence of pulmonary embolism (p<0.05). Also, patients whose DVT resolved were younger (p<0.05). There was no difference among the 4 groups in mortality, placement of Greenfield filters, mean PT, mean PTT, mean number of ultrasound exams per patient, or mean follow-up time over which the exams took place. Proximal extension of DVT documented by repeat duplex ultrasound is a significant risk factor for pulmonary embolism. Repeat duplex ultrasound can identify a group of patients who may benefit from insertion of an intracaval filter device.

Hemodynamics of infrapopliteal PTFE bypasses and adjunctive arteriovenous fistulas.

PURPOSE: Blood flow, pressure and peripheral resistance in patients with established polytetrafluoroethylene (PTFE) grafts and adjunctive arteriovenous fistulas (AVF) have rarely been investigated. To better elucidate the effects of this AVF, we obtained noninvasive measurements of hemodynamic variables in patients with infrapopliteal PTFE grafts and an AVF. METHODS: . Systolic, mean and diastolic arm and toe pressures were measured with an oscillometric technique employed in automatic blood pressure monitors. Peak-systolic velocity, end-diastolic velocity and flow rates at the graft and recipient distal artery were measured with duplex ultrasound. Resistance for the leg and foot in peripheral resistance units ( PRU ) was estimated as mean arm pressure divided by graft flow rate and as mean toe pressure divided by distal artery flow rate respectively. We analyzed data from 21 patients. Toe pressures were measurable in 13 patients. Bypass graft inflow was at the external iliac artery in 11 patients, common femoral in six, common iliac in two and superficial femoral in two. The distal anastomosis was at the anterior tibial artery in 10 patients, peroneal in seven and posterior tibial in four patients. RESULTS: . Graft systolic and diastolic velocities were 91+/-46 (mean+/-sd) and 38+/-31 (mean+/-sd) cm/s respectively. Toe systolic pressure averaged 81+/-28 (mean+/-SD) mmHg with a corresponding toe/brachial index (TBI) of 0.53+/-0.18 (mean+/-SD). The ratio between arm mean pressure, 104+/-20 (mean+/-SD) mmHg, and graft flow rate, 413+/-290 (mean+/-sd) ml/min, yielded an estimated leg resistance of 0.32+/-0.20 peripheral resistance units (PRU) (mean+/-sd). The ratio between mean toe pressure, 51+/-21 (mean+/-SD) mmHg, and distal artery flow rate, 37+/-26 (mean+/-SD) ml/min, produced an estimated foot resistance averaging 1.66+/-1.18 PRU (mean+/-sd). CONCLUSIONS: Average graft flow rate was five times greater than flow reported for standard tibial bypasses. Although distal artery flow rate and graft peak systolic velocity were within reported normal ranges, mean toe pressure and toe-brachial index were below normal. Leg and foot resistances were decreased. These data suggest that bypasses with arteriovenous fistulas have increased flow, desirable for graft patency, but may affect distal perfusion pressure.

Noninvasive ultrasound measurement of shear rate in leg bypass grafts.

Shear has been implicated in the etiology of atherosclerosis, thrombosis and graft stenosis. We measured shear rate noninvasively in infrainguinal bypasses. Velocity profiles were recorded from 35 femoropopliteal and 40 tibial grafts. Flow rate (Q), systolic shear rate (SSR), diameter, and bluntness factor (BF) were measured at midgraft using ultrasound (US). Mean shear rate (MSR) was calculated from flow and diameter. SSR, 671 +/- 260 (SD) vs. 659 +/- 304 s(-1) (p = 0.85), and MSR, 168 +/- 84 vs. 193 +/- 110 s(-1) (p = 0.26), were similar for popliteal and tibial bypasses, but differences in Q, 126 +/- 57 vs. 104 +/- 38 mL/min, were borderline significant (p = 0.058). Popliteal grafts had larger diameters, 5.2 +/- 1.1 mm vs. 4.7 +/- 0.8 mm (p = 0.048), and BF, 3.4 +/- 0.9 vs. 2.8 +/- 0.7 (p = 0.0014). Shear rates were obtained noninvasively in humans. Larger diameters in popliteal vs. tibial bypasses did not result in lower shear rates and were compensated for by larger bluntness factors. Velocity profile bluntness cannot be ignored in shear rate analysis.

Femoral pseudoaneurysm thrombinjection.

BACKGROUND: The risk of pseudoaneurysm (PSA) increases with the number of catheterizations performed for cardiovascular diagnosis and therapy. Thrombin injection, or "thrombinjection," is an alternative to ultrasound-guided compression or surgical repair. Thrombinjection is effective and economical, but the specter of systemic arterial thrombosis hinders its wide application. We report cautionary steps taken prior to injection and lessons learned during our first 20 cases. METHODS AND RESULTS: Thrombinjection was performed under ultrasound (US) guidance in 12 women and 8 men with PSA after femoral catheterization. PSA varied in size from 17 to 39 mm with neck openings from 1.5 to 3.9 mm. Under local anesthesia and US longitudinal view, a 20-gauge US needle tip was placed in the PSA away from the neck. With 12 cases under 600 units, 100 to 2,300 units of thrombin (1,000 U/mL) were injected slowly. Slow injection, positioning of the ball of thrombus formed at the needle tip, probe compression, and combined or interchangeable use of US color flow and B-mode were the essential techniques utilized. All PSA thrombosed successfully on the first treatment. One patient had fever and another returned for compression treatment of a second, not recurrent, PSA. CONCLUSIONS: Successful thrombinjection was accomplished by focusing on common femoral artery PSA with small neck openings, avoiding arteriovenous fistulas, and using standard thrombin concentration, US needle, state of the art ultrasonography, slow injection, thrombus ball positioning, and adjunctive probe compression.

Posterior transverse plication technique for treatment of redundant internal carotid artery during endarterectomy.

PURPOSE: Posterior transverse plication (PTP) has gained popularity as a technique to correct redundancy of the internal carotid artery during endarterectomy. The safety of this technique in large series of patients has not been extensively studied. We investigated 876 primary carotid endarterectomies (CEAs) performed at our institution over the last six years to determine the safety of this technique. METHODS: Indication for surgery was carotid stenosis >/=70% in 341 (39%) symptomatic and 535 (61%) asymptomatic cases. Preoperative imaging consisted of duplex ultrasound alone or combined with magnetic resonance angiography. Patients were divided into four groups related to surgical technique: CEA+PTP+8mm patch (group Ia), CEA+PTP+10mm patch (group Ib), CEA+patch (group II) and CEA+primary closure (group III). There were 43, 39, 581 and 213 patients in groups Ia, Ib, II and III, respectively. No statistical differences in age, sex or risk factors for atherosclerotic disease were noted among the groups. Postoperative duplex ultrasonography was used at 2weeks and every 6months thereafter to evaluate the adequacy of the repair and presence of complications such as pseudoaneurysm formation and extrinsic compression by the excluded carotid segment. RESULTS: The 30-day mortality was 1.2%, 0.6% and 0.3% for groups I, II and III, respectively. Stroke rates for the same period were 0%, 0.6% and 0.8% for groups I, II and III, respectively. Duplex ultrasonography demonstrated significant stenosis (>/=50%) in two (5%) patients in group Ia at 12months. No restenosis was observed in group Ib. For groups II and III the rates of restenosis were 1.5% and 0.8%. One patient in group II developed a pseudoaneurysm after 7months. CONCLUSION: Posterior transverse plication safely corrects redundancy of the internal carotid artery during endarterectomy without causing early significant restenosis. Continued follow-up in a larger group of patients to determine long-term efficacy and correlation between patch size and restenosis rate is warranted.

Diameter comparison of saphenous vein bypasses for popliteal aneurysm versus peripheral arterial occlusive disease in matched subjects.

Previous research has suggested that arterial aneurysm might result from a systemic tendency to dilatation. This systemic effect would involve both arterial and venous dilatation. The authors investigated whether venous grafts implanted to bypass popliteal artery aneurysms (PAA) had larger diameters than those implanted to treat peripheral arterial occlusive disease (PAOD). They compared representative diameters of 20 vein grafts implanted for PAA with matched bypass grafts implanted for PAOD. Graft diameters were obtained by means of CVI-Q M-mode ultrasound imaging. Each PAA patient/graft was matched to an equivalent PAOD patient/graft based on the patient's gender and age and the vein graft type and distal anastomosis. Secondarily, graft proximal anastomosis was matched in 60% (12/20) of the cases. Age was matched if the difference was < or = 4 years. Average age at the time of surgery was 68 +/-12 years for PAA and 68 +/-13 for PAOD groups. There were 11 reversed greater saphenous vein (GSV), 2 nonreversed GSV, and 7 in situ GSV in each group. Distal anastomoses were at the popliteal (15), peroneal (3), posterior (1), and anterior tibial (1) arteries in each group. Matching was not possible for lesser saphenous and cephalic vein grafts or bypasses to the tibial-peroneal trunk. Graft diameters were significantly larger for the PAA group, 6.24 +/-0.66 mm (standard deviation), than for the PAOD group, 5.73 +/-0.69 mm (p < 0.02, Mann-Whitney U test). Of 10 bypasses with diameter >6.5 mm, 8 were implanted for PAA. If these 10 largest bypasses were eliminated from the calculations, the mean graft diameters were 5.82 +/-0.51 mm and 5.57 +/-0.52 mm for the PAA and PAOD groups, respectively (p = 0.28). Bypass grafts implanted in PAA patients had significantly greater diameters than grafts implanted in PAOD patients. This finding, however, was due to a subgroup of grafts with diameters >6.5 mm. Perhaps systemic abnormalities associated with PAA should be first studied in patients with large vein grafts or large original veins.

Routine preoperative carotid duplex scanning in patients undergoing open heart surgery: is it worthwhile?

It has been reported that carotid screening may be cost-effective in patient populations in which the prevalence of severe carotid stenosis exceeds 4.5%. In order to identify potential patient populations who might benefit from carotid screening, we examined the results of preoperative duplex scanning in patients undergoing open heart surgery. Between January 1995 and July 1998, 3708 patients (59% male, 41% female) underwent open heart surgery at our institution. Of these, 3081 underwent coronary artery bypass grafting (CABG), 364 underwent valve replacement (VR), and 263 underwent CABG and VR. The ages of these patients ranged from 40 years to 98 years (mean 68 +/- 11 years). The risk factors analyzed included hypertension (HTN), 59%; smoking (Smk), 53%; and diabetes (DM), 33%. Patients were divided into three groups according to their age. Group A consisted of the 835 patients who were < or = 60 years old, group B consisted of 2474 patients ranging from 61 years to 80 years old, and group C consisted of 399 patients who were > or = 81 years old. All patients underwent bilateral preoperative carotid duplex scans at an Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL)-accredited vascular laboratory. Statistical analyses were performed using chi-squared, Fisher's exact test, linear regression, and multivariate analysis. From our results we concluded that carotid screening is not recommended for patients under 60 years of age who are undergoing CABG unless they present with a minimum of two of the following major risk factors: hypertension, diabetes, or smoking. However, carotid screening is recommended for all patients undergoing open heart operations who are over the age of 60 years old, regardless of the absence of associated risk factors.

Upper extremity deep venous thrombosis: an underrecognized manifestation of a hypercoagulable state.

Although lower extremity deep venous thrombosis (LEDVT) has been associated with a hypercoagulable state, there are scant data available for patients presenting with upper extremity deep venous thrombosis (UEDVT). Therefore, we conducted a prospective study to determine whether such an association exists for UEDVT. Fifty-two patients who presented with UEDVT at our institution from August 1996 to June 1997 underwent a hematological profile consisting of activated protein C (APC) resistance, antithrombin III (ATIII) level and activity, factor V mutation (arginine 506 to glycine), protein C level and activity, protein S level and activity, factors II and X activity, lupus anticoagulant, and cardiolipin antibody. This represented 68% (52/76) of the total number of patients in whom the diagnosis of UEDVT was made by duplex ultrasonography during this time period. The ages ranged from 9 to 97 (mean 63 +/- 23 years). There were 22 males and 30 females. Twenty-five patients (48%) had a central venous line in place, 4 patients (8%) had a pacemaker, 14 patients (27%) had a history of neoplasm, and 7 patients (13%) had concomitant LEDVT. The results of our study showed that a hypercoagulable state may be an underappreciated contributing factor in the development of UEDVT. Contrary to prior belief that three sets of tests are needed to confirm the presence of a hypercoagulable state, these data also suggest that only two tests may be needed.

Lower-extremity revascularisation without preoperative contrast arteriography in 185 cases: lessons learned with duplex ultrasound arterial mapping.

PURPOSE: we have previously reported our experience with lower-extremity duplex-ultrasound arterial mapping (DUAM) compared to contrast arteriography (CA) to predict lower-extremity bypass sites. The present study evaluates arterial revascularisation procedures for chronic limb ischaemia based on DUAM. MATERIALS AND METHODS: from January 1998 to July 1999, 195 patients (128 men, 67 women) underwent 211 lower-extremity revascularisation procedures based on DUAM. Indications for surgery were tissue loss, severe claudication, rest pain and popliteal aneurysm in 57%, 25%, 14% and 4% of the limbs, respectively. The mean age was 72+/-12 years and risk factors such as diabetes, hypertension, tobacco use, coronary artery and end-stage renal disease were present in 53%, 58%, 53%, 50% and 12% of the patients, respectively. Previous revascularisation procedures had been performed in 23% of the limbs. Preoperative evaluation consisted of DUAM alone (185) or of a combination of DUAM and CA (29 limbs). CA was deemed necessary due to a combination of technical difficulties that jeopardized adequate sonographic imaging and presence of disadvantaged run-off for medico-legal reasons. DUAM consisted of direct imaging of all major arteries from the distal aorta to the pedal circulation. Optimal inflow and outflow bypass anastomotic sites were selected according to a diagram based on DUAM. Adequacy of the inflow was additionally assessed by common-femoral-artery waveform and confirmed by intraoperative pressure measurements. Post-bypass CA was obtained to verify patency of the run-off. RESULTS: DUAM procedure time averaged 75+/-26 min. For patients who underwent only DUAM, the distal anastomosis was to the popliteal artery in 91 cases and to tibial or pedal arteries in 58 cases. Distal anastomosis was proximal to a significant lesion in two cases that required jump grafts. Cumulative patency rates at 1 and 3 months for popliteal bypasses were 96% and 90%, and for infrapopliteal bypasses 90% and 83%, respectively. Inflow procedures to the femoral artery, patch and balloon angioplasties accounted for the remaining 40 cases. Four primary amputations were performed after CA confirmed DUAM findings. CONCLUSIONS: contrary to general belief, these data show that high-quality arterial ultrasonography represents a safe alternative to preoperative CA, even for infrapopliteal bypasses. This non-invasive approach may be especially useful for patients with contrast allergy or impaired renal function.

Diameter-reflux relationship in perforating veins of patients with varicose veins.

PURPOSE: Treatment of chronic venous valvular insufficiency requires understanding of the hemodynamics of perforating veins. To preserve normal veins or veins that can function normally once primary sources of valvular insufficiency are removed, a better understanding of the diameter-reflux relationship is desirable. We measured reflux and diameters in 500 perforating veins of patients with varicose veins (C(2)E(P)A(SP)P(R)). METHODS: Color flow duplex ultrasonography scanning was performed with the patient standing. Perforating veins were mapped medially in the thigh and medially, laterally, and posteriorly in the calf. Reflux was defined as reverse flow that lasted longer than 0.5 seconds. Diameters were measured on B-mode transverse projections at the crossing of the fascia. Competent versus incompetent vein diameters were compared by means of Student t test, one-way analysis of variance, and Bonferroni t test. RESULTS: Diameters of competent and incompetent perforators averaged 2.5 +/- 0.9 mm (n = 17) and 4.7 +/- 1.9 mm (n = 17) at the medial thigh (P <.0002), 2.2 +/- 0.8 mm (n = 179) and 3.7 +/- 1.0 mm (n = 210) at the medial calf (P <.0001), 2.2 +/- 0.6 mm (n = 13) and 3.5 +/- 0.8 mm (n = 37) at the posterior calf (P <. 0001), and 2.1 +/- 0.8 mm (n = 9) and 3.3 +/- 0.7 mm (n = 18) at the lateral calf (P <.003), respectively. Perforating vein diameters of 3.5 mm or larger in the calf and thigh were associated with reflux in more than 90% of the cases. CONCLUSION: An enlargement in the diameter of the perforating veins of 1 to 1.5 mm in the calf or 2 mm in the thigh of patients with varicose veins could be the difference between normal flow and reflux. Further studies are needed to confirm if elimination of reflux in patients with primary varicosity will transform incompetent perforators to competent ones.

The use of duplex ultrasound arterial mapping as an alternative to conventional arteriography for primary and secondary infrapopliteal bypasses.

BACKGROUND: For more than 1 decade, duplex ultrasonography has been investigated as a potential replacement for invasive contrast arteriography (CA) prior to lower extremity revascularization. While some authors advocate the reliability of this methodology for infrainguinal imaging, revascularizations based on duplex ultrasonography alone are seldom reported. Our initial experience with duplex ultrasound arterial mapping (DUAM) for primary and secondary infrapopliteal bypasses performed without preoperative CA is reported in this series. METHODS: Twenty-eight infrapopliteal bypasses based on DUAM alone (26) and combined DUAM and CA (2) were performed. Indications for surgery were tissue loss in 22 cases and rest pain in 6. Eight patients (29%) had at least 1 previous ipsilateral revascularization. A schematic anatomical drawing based on DUAM helped the selection of optimal inflow and outflow bypass sites. Bypasses originated from the femoral arteries in 17 cases, external iliac in 3, and popliteal in 4, and from a previous graft in 4. The distal anastomosis was to the dorsalis pedis in 12 cases, posterior tibial in 7, anterior tibial in 6, and peroneal in 3. RESULTS: DUAM revealed unobstructed inflow in 24 cases, significant iliac stenosis in 1, and in 3 cases imaging was not possible owing to obesity. A pressure gradient of 15 mm Hg between donor and radial artery confirmed the stenosis diagnosed by DUAM, and was successfully treated with balloon angioplasty and stent placement. A single infrapopliteal runoff artery was identified by DUAM in 22 cases, 2 in 4 cases, and 3 in 2 cases. Preoperative CA was performed in 2 instances because of severe arterial calcification. Completion arteriography matched the run-off status predicted by DUAM in 25 out of 26 cases (96%). DUAM missed a significant anterior tibial artery stenosis that required a distal graft extension. One-, 3-, and 6-month patency rates were 96%, 85%, and 62%, respectively. Limb salvage rate was 86%. CONCLUSIONS: This early experience shows that DUAM may be a safe alternative to invasive conventional arteriography for the majority of patients (89%) presenting with critical ischemia and in need of infrapopliteal bypasses.

Carotid arterial ultrasound scan imaging: A direct approach to stenosis measurement.

PURPOSE: Management decisions regarding carotid artery disease are critically dependent on stenosis but have been made difficult because of conflicting methods used to determine such stenosis. The increasing use of duplex ultrasound scanning has conventionally depended on Doppler velocity measurement, an indirect method for calculating carotid stenosis. Recent technical advances have improved the quality of B-mode/color-flow ultrasound scan imaging (USI). We tested prospectively whether USI was clinically effective as the primary criterion for estimating carotid stenosis. METHODS: Transverse and longitudinal USI, Doppler velocity, and arteriography data were obtained sequentially and independently for 713 carotid bifurcations. The internal carotid artery (ICA) residual lumen, the local outer diameter at the stenotic site, and the diameter distal to the bulb were measured in a representative USI longitudinal section. The peak systolic velocity and the end diastolic velocity (EDV) were measured at the stenosis. Local stenosis as determined with USI was compared with the x-ray arteriographic clinical radiology interpretation (XRI). As the primary method, radiologists compared the residual lumen with the distal ICA diameter, as recommended by the North American Symptomatic Carotid Endarterectomy Trial and the Asymptomatic Carotid Atherosclerosis Study. Analysis was by means of the USI positive predictive value (PPV) and negative predictive value (NPV) of the XRI findings, with the assumption that 80%, 70%, and 60% local stenosis with USI related to 70%, 60%, and 50% stenosis with XRI, respectively. RESULTS: All 56 ICA occlusions as determined with USI were confirmed with XRI. When the USI showed 80% to 99% stenosis, the PPV of the XRI showing 70% to 99% stenosis was 94% (116/123). Two ICAs that were shown to be severely diseased with USI appeared to be occluded with XRI. For <50% stenosis shown with USI, the prediction of <50% stenosis shown with XRI was 94% (253/269). For borderline stenosis in the 50% to 79% range with USI, the addition of velocity criteria to USI data improved both the PPV and the NPV. In the range of 70% to 79% stenosis with USI, the PPV improved from 82% (76/93) to 91% (53/58) for the subgroup with an EDV of more than 80 cm/s. For the range of 60% to 69% stenosis with USI, the PPV improved from 75% (71/95) to 95% (21/22) for the subgroup with an EDV of more than 80 cm/s. In the range of 50% to 59% stenosis with USI, the NPV improved from 69% (53/77) to 93% (14/15) for the subset with a peak systolic velocity of less than 100 cm/s. CONCLUSION: On the basis of the USI data alone, a prediction of arteriographic findings was possible at the 95% level for occlusion and severe stenosis and for ruling out hemodynamically significant stenosis. The addition of velocity data improved prediction in borderline degrees of stenosis. USI was effective for quantifying clinically significant degrees of stenosis.

Carotid screening with duplex ultrasound in elderly asymptomatic patients referred to a vascular surgeon: is it worthwhile?

The purpose of this study is to prospectively determine the outcome of carotid duplex ultrasound screening in patients referred to a vascular surgeon for problems other than carotid disease. During a recent 12-month period, 307 patients age 65 years and older (mean 76 +/- 8 years) were referred to one vascular surgeon for problems other than cerebrovascular disease. Fifty-one percent of the patients were male, 49% were female, 32% were diabetic, 32% were hypertensive, 31% smoked, 20% had coronary artery disease, and 64% had peripheral arterial occlusive disease. All patients underwent a screening duplex ultrasound exam of the carotid arteries as approved by our Institutional Review Board. The results of our study showed that the prevalence of asymptomatic carotid artery stenosis >70% among patients seen by a vascular surgeon for problems other than cerebrovascular disease is high (21%) and is associated with male gender, advanced age, diabetes mellitus and having quit smoking. Continued carotid artery duplex screening is warranted in this patient population greater than age 65 years.

Values and limitations of duplex ultrasonography as the sole imaging method of preoperative evaluation for popliteal and infrapopliteal bypasses.

The purpose of this study was to evaluate whether duplex ultrasound arterial mapping (DAM) can reliably replace standard arteriography (SA) in the preoperative assessment of candidates for popliteal and infrapopliteal bypasses. This is the report of a two-phase study undertaken at our institution from July 1997 to May 1998. Carefully performed DAM averted the need for preoperative SA (51 of 58 procedures). The results of this study can be used as an impetus to initiate larger, multicenter protocols to further evaluate this newer noninvasive approach for patients presenting with severe lower-limb ischemia.

Ultrasound echogenicity in experimental venous thrombosis.

This study characterizes the echogenicity of experimentally induced venous thrombosis. Venous duplex imaging (Diasonics Spectra) was performed of the rat (n 12) and primate (n 3) inferior vena cava (IVC). Thrombosis was induced by IVC ligation at the level of the renal veins (rat, baboon) or balloon occlusion (baboon) of the IVC at the renal vein and iliac vein bifurcation level. Sham-treated rats served as controls. B-mode images were stored for off-line computer analysis. Fixed depth gain control curves allowed for measuring gain-corrected echogenicity units over the IVC in both a longitudinal and transverse orientation. In rat studies, thrombus was removed at time of euthanasia and dissolved, allowing for fibrin monomer determination using a chromogenic assay. Echogenicity values generally increased over time in both rat and primate studies. Significant differences between ligated and sham-treated rats were noted at each time point measured (6 h, 2 days, and 6 days after IVC ligation) and fibrin monomer values correlated (p < 0.05) with echogenicity units. In primate studies, echogenicity values significantly were different from baseline values at all time points measured (6 h, 2 days, 6 days, and 13 days after thrombus induction). Duplex ultrasound can be used to quantitate thrombus echogenicity, which correlates to fibrin content. Such measurement may potentially allow for improved thrombus age determination and the noninvasive quantitation of thrombus progression/resolution.