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T F O'Donnell

Publications and source records attributed to T F O'Donnell.

At least 19 recordsLinked to original sources
PubMed2000

The Balanced Budget Act: potential implications for the practice of vascular surgery.

PURPOSE: Previous study results have shown a favorable impact on stroke rate with an increasing hospital volume of carotid endarterectomies (CEAs). This is not only the most frequently performed peripheral vascular procedure in the United States but also perhaps the most widely dispersed procedure relative to hospital type. Medical centers have adopted various strategies to lower the cost of hospitalization by reducing the length of stay (LOS), the major component of hospital cost. By 2002, the Balanced Budget Act is projected to reduce Medicare provider payments to academic medical centers (AMCs) by 15.5%, a reduction that is twice that for minor or nonteaching hospitals. We assessed the relationships between hospital costs, CEA volume, and stroke-mortality rates in AMCs and non-AMCs in Massachusetts. METHODS: With patient level data from the Massachusetts Division of Health Care Finance and Policy and with hospital cost and charge reports from the Health Care Financing Administration, HealthShare Technology provided data for all the patients discharged from a Massachusetts hospital who underwent CEA (n = 10,211) during the fiscal years 1995, 1996, and 1997, including cost, LOS, and disposition. The outcomes were further defined with in-hospital stroke and mortality rates. Five high volume AMCs (HVAMCs) were compared with all other nonacademic hospitals, which were further subdivided by annual volume into high volume non-AMCs (> or =50 cases), medium volume non-AMCs (24-49 cases), and low volume non-AMCs (12-23 cases). Statistical analysis was performed with analysis of variance to compare the means of all the cost and LOS data, and chi(2) test was used for comparison of incidence (significance assumed for P < or =. 05). RESULTS: Hospital costs were comparable among the four hospital types during individual years and averaged $6200, but HVAMCs were significantly more expensive overall, with a mean cost of $7882. The only centers to decrease their costs during the years evaluated were the HVAMCs, from $8706 to $6784. Length of stay did not differ among the groups in any year or overall, with a mean of 3.8 days, but did decrease between years at HVAMCs from 3.9 to 2.5 days. The combined stroke-mortality rates were significantly less at the HVAMCs (0.9%) than at either the high volume non-AMCs (1.9%) or the medium volume non-AMCs (2.5%). There was no significance in the analysis results of all the data within the low volume non-AMCs. CONCLUSION: Patients in HVAMCs have the best outcomes after CEA. Despite the achievement of significant efficiencies, AMCs have a small cushion to reduce further either LOS or resources to maintain a competitive cost position and to compensate for the fixed expenses of academic medicine. The Balanced Budget Act raises an equity concern for AMCs because it differentially affects the centers with the best outcomes. The financial implication of this may be a direct incentive for procedures to be done in centers with less optimal outcomes.

Academic Medical Centers↗
PubMed1999

Adjuvant techniques for the management of large carotid body tumors. A case report and review.

Although the first successful resection of a carotid body tumor was reported over 100 years ago this operation remains technically challenging with many potential pitfalls. The case of a man with a large (8 cm) carotid body tumor will be presented in order to identify key issues that pertain to effective diagnostic and therapeutic modalities. A multidisciplinary team (vascular surgeon, neurosurgeon, neuroradiologist, interventional radiologist and oromaxillofacial surgeon) provided specific expertise on each aspect of the patient's evaluation and treatment. Adjuvant techniques employed in this case included angiographic tumor embolization, jaw subluxation, strap muscle division, nasotracheal intubation, carotid resection and saphenous vein interposition grafting.

Aged↗
PubMed1998

Endoscopic in situ bypass. A gentler dissection.

We believe that this is the first report of a gasless endoscopic in situ bypass technique. We have pursued this minimally invasive procedure with the hope that wound complications and operative time might be improved without compromising graft patency. Having demonstrated the feasibility of minimally invasive lower-extremity bypass we would urge further study to assess the safety and efficacy of this promising approach.

Endoscopy↗
PubMed1998

Reduction of hospital resources utilization in vascular surgery: a four-year experience.

PURPOSE: Managed care whether through risk or through capitated contracts results in reduction in resources, reduced length of hospital stay, and reduced utilization of hospital resources (collectively referred to as resource reductions). These resource reductions will become even more noticeable as a greater proportion of Medicare patients who need vascular operations select a managed-care senior product. We examined the results of a 4-year experience with resource management in an academic vascular surgery practice during which best practice plans were developed and implemented. METHODS: We analyzed hospital cost data, which included both total hospital and intensive care unit length of stay, average units per operation for laboratory, pharmacy, and radiology services and operating room and direct hospital costs for 257 carotid endarterectomies performed over fiscal years (FY) 1994, 1995, 1996, and 1997 (6 month data) and 175 infrainguinal bypass procedures performed during the same period. RESULTS: For carotid endarterectomy, length of stay decreased 66% over the 4-year period to an average of 2.07 days in FY97. Both radiology and pharmacy utilization were reduced after the first year of institution of best practice plans (56% and 32% respectively) with 4-year total reductions of 86% and 55% by FY97. The most notable changes included elimination of routine postoperative laboratory testing, use of aspirin rather than low-molecular-weight dextran, emphasis on oral rather than intravenous vasoactive drugs, and routine use of duplex scanning alone rather than angiography for diagnosis after FY94-95. The length of operating room time for carotid endarterectomy remained relatively constant from FY94 to FY97. As a result of these multiple factors, our study showed a 30% decrease in total average direct hospital costs for carotid endarterectomy from $9974 to $7002 in this 4-year period. Infrainguinal bypass graft procedures showed a progressive decrease in total cost of 28% for patients without complications to $15,186 but remained unchanged for those with complications. Laboratory use, pharmacy use, and radiology use were not significantly different. CONCLUSIONS: Case management for patients undergoing carotid endarterectomy and infrainguinal bypass grafting involving an integrated team of vascular surgeons, surgical house staff, a dedicated vascular nurse, and a social work case manager resulted in dramatic reductions both in length of stay and hospital resource utilization. As these costs decreased, operating room expenses assumed increasing importance. Operating room costs account for 60% of the direct costs of carotid endarterectomy and a comparable percentage for uncomplicated infrainguinal bypass grafting. Further substantial reductions in direct hospital costs will depend primarily on reductions in operating room costs, particularly those related to length of time in the operating room.

Costs and Cost Analysis↗
PubMed1997

Subfascial endoscopic perforator ligation: an analysis of early clinical outcomes and cost.

PURPOSE: Early results of subfascial endoscopic perforator surgery (SEPS) were examined. Data on ulcer healing, complications, and costs are presented. METHODS: Data were prospectively collected for all patients who underwent SEPS at our institution. A concurrent control group was not available because primary open perforator ligation is no longer performed at our hospital. Preoperative assessment included duplex scanning (valve closure times and perforator mapping), plethysmography, and phlebography. Completeness of therapy was assessed with postoperative duplex mapping of perforating veins. Clinical status was monitored after surgery, and actual costs, including equipment, personnel, and facilities management, are reported. RESULTS: Eighteen procedures were performed in 15 patients (mean age, 52 years; range, 42 to 65 years). Two patients underwent bilateral SEPS, and one patient underwent a second procedure on the same leg. Active ulceration (class 6) was present in 14 of 18 limbs (78%), recently healed ulcers (class 5) in two of 18 (11%), and lipodermatosclerosis with edema (class 4) in two. Deep venous insufficiency was present in 14 of 18 (78%). The number of perforating veins ligated per leg ranged from 0 to 12 (mean, 4.3). Follow-up ranged from 3 to 64 weeks (mean, 22 weeks). Complete ulcer healing occurred in eight of 14 limbs (57%) at a mean of 14 weeks. Reduction in ulcer size was noted in four of 14 (29%), and two limbs were not improved. There were no new ulcers. Residual perforating veins were noted in four of 18 limbs. None of the limbs with residual perforating veins had complete healing of ulceration. Operating room costs were higher than those associated with limited-incision open perforator ligation ($2570 vs $1883). CONCLUSION: These preliminary data suggest that when used as part of a treatment plan to correct deep and superficial venous insufficiency SEPS results in a high rate of wound healing, with no recurrent ulceration in this series. Increased operating room costs associated with longer operations and greater disposable expenses will likely be overcome by shortened length of stay and diminished wound complications. These findings emphasize the importance of ligating all incompetent perforating veins, as ulcer healing was never achieved when residual perforating veins were found at follow-up.

Case-Control Studies↗
PubMed1997

Safety, feasibility, and early efficacy of subfascial endoscopic perforator surgery: a preliminary report from the North American registry.

PURPOSE: The North American Subfascial Endoscopic Perforator Surgery (NASEPS) Registry was established to evaluate the safety, feasibility, and efficacy of minimally invasive endoscopic Linton operations for treatment of chronic venous insufficiency. METHODS: Retrospective analysis was performed on the clinical data of 151 patients who underwent attempt at 158 SEPS in 17 medical centers in the United States and Canada between June 1993 and February 1996. RESULTS: SEPS was completed on 155 limbs of 148 patients, 81 male and 67 female (mean age, 56 years; range, 27 to 87 years). Three procedures were aborted. Seven patients had bilateral procedures (data from one limb were analyzed). One hundred four limbs (70%) had active ulcers, and 22 (15%) had healed ulcers. A single endoscopic port without insufflation was used in 66 procedures (45%) and laparoscopic instrumentation, with two or three ports, in 82 (55%), with CO2 insufflation in 78 (53%). A tourniquet was used on 112 patients (76%). Concomitant venous procedures were performed in 106 patients (72%; saphenous stripping in 71, high ligation in 17, varicosity avulsion in 85). No early deaths or thromboembolism occurred. Complications included wound infections (9), superficial thrombophlebitis (5), cellulitis (4), and saphenous neuralgia (10). Seven patients with wound infection had open ulcers; nine of 10 with neuralgia had concomitant procedures. A roll-on tourniquet caused skin necrosis in one patient. The clinical score improved from 9.4 to 2.9 after surgery (p < 0.0001). Mean follow-up was 5.4 months; 31 patients had > or = 6 months follow-up. Ulcers healed in 88% (75 of 85); recurrence or new ulcer was reported in 3% (4 of 120). CONCLUSIONS: The SEPS modified Linton operation appears safe, with no postoperative deaths or early thromboembolism. Wound infection after SEPS remains important. Early results indicate rapid ulcer healing. Prospective evaluation of long-term results is warranted.

Adult↗
PubMed1997

Estrogen inhibits the vascular injury response in estrogen receptor alpha-deficient mice.

The atheroprotective effects of estrogen in women are well recognized, but the underlying mechanisms responsible are not well understood. Blood vessel cells express the classic estrogen receptor, ER alpha (ref. 2-6), and are directly affected by estrogen, which inhibits the development of atherosclerotic and injury-induced vascular lesions. We have generated mice in which the ER alpha gene is disrupted and have used a mouse model of carotid arterial injury to compare the effects of estrogen on wild-type and estrogen receptor-deficient mice. Increases in vascular medial area and smooth muscle cell proliferation were quantified following vascular injury in ovariectomized mice treated with vehicle or with physiologic levels of 17 beta-estradiol. Surprisingly, in both wild-type and estrogen receptor-deficient mice, 17 beta-estradiol markedly inhibited to the same degree all measures of vascular injury. These data demonstrate that estrogen inhibits vascular by a novel mechanism that is independent of the classic estrogen receptor, ER alpha.

Animals↗
PubMed1997

Surgical reconstruction for deep venous insufficiency.

All patients with significant venous stasis disease should undergo noninvasive evaluation to determine the magnitude, precise location, and etiology of the problem (i.e. obstruction and/or reflux). Patients who fail aggressive medical therapy (compression and skin care) and who have significant symptoms should be considered candidates for surgical correction. The majority of patients screened will have a significant component of superficial venous insufficiency with or without the presence of incompetent perforating veins. In this case we address the superficial and perforating venous systems prior to consideration of deep venous reconstruction. When correction of superficial venous incompetence fails to improve the patient's symptoms, they are then considered for deep venous reconstruction. Patients with primary venous insufficiency are typically good candidates for direct valvuloplasty performed using the open or angioscopic techniques, while patients with damaged (post thrombotic) or absent valves are best managed by vein valve transplantation or segmental transposition. Results for both valvuloplasty and vein valve transplantation demonstrate good intermediate term valvular patency and ulcer healing. It appears that when used as part of a complete treatment protocol addressing superficial, deep, and perforating venous systems, as well as attention to skin care and appropriate compressive therapy that surgical reconstruction for deep venous reflux affords significant benefit to our patients.

Adult↗
PubMed1996

Who needs surveillance of the contralateral carotid artery?

BACKGROUND: Although the value of carotid endarterectomy has been proven, postoperative surveillance remains controversial. The purpose of this study was to determine the natural history of disease progression in the contralateral carotid artery by duplex surveillance, and to assess the cost of stroke prevention on this contralateral side. METHODS: Vascular laboratory records were reviewed to identify carotid endarterectomy patients who had two or more duplex studies between 1984 and 1995. Critical stenosis was defined as > or = 75% area reduction. RESULTS: In all, 324 patients were followed up with duplex scans for 1 month to 11 years (mean 30.3 months). The only factors that correlated with progression to critical stenosis were age and initial stenosis. Overall, 19.5% of patients progressed to critical stenosis within 5 years while the high-risk groups with age > 65 years or initial stenosis > or = 50% progressed to critical disease in 27% and 39%, respectively (P < or = 0.05). The cost per stroke prevented ranged from $143,500 to $418,200 when stratified by initial stenosis. CONCLUSION: Patients who have undergone a carotid endarterectomy demonstrate a propensity for progression of carotid stenosis in the unoperated (contralateral) artery. The cost/benefit ratio may be improved by varying the intensity of duplex surveillance of the contralateral carotid based on the patient's age and initial degree of stenosis.

Adult↗
PubMed1996

Duplex assessment of venous reflux and chronic venous insufficiency: the significance of deep venous reflux.

PURPOSE: This study was undertaken to examine the role of superficial and deep venous reflux, as defined by duplex-derived valve closure times (VCTs), in the pathogenesis of chronic venous insufficiency. METHODS: Between January 1992 and November 1995, 320 patients and 500 legs were evaluated with clinical examinations and duplex scans for potential venous reflux. VCTs were obtained with the cuff deflation technique with the patient in the upright position. Imaging was performed at the saphenofemoral junction, the middle segment of the greater saphenous vein, the lesser saphenous vein, the superficial femoral vein, the profunda femoris vein, and the popliteal vein. Not all patients had all segments examined because tests early in the series did not examine the profunda femoris or lesser saphenous vein and because some patients had previous ligation and stripping or venous thrombosis. VCTs were examined for individual segment reflux, grouped into superficial and deep systems, and then correlated with the clinical stage as defined by the SVS/ISCVS original reporting standards in venous disease. Segment reflux was considered present if the VCT was greater than 0.5 seconds, and system reflux was considered present if the sum of the segments was greater than 1.5 seconds. Between-group differences were analyzed with analysis of variance and post hoc tests where appropriate. RESULTS: Sixty-nine limbs studied were in class 0, 149 limbs were in class 1, 168 limbs were in class 2, and 114 limbs were in class 3. VCTs in the superficial veins were significantly lower in class 0 than in the other clinical classes. There was no difference in superficial reflux in the symptomatic limbs (classes 1 to 3). Reflux VCTs in the superficial femoral and popliteal veins increased as the clinical symptoms progressed, with a significant increase in class 3 ulcerated limbs when compared with nonuclerated limbs. The incidence of deep venous reflux was 60% in class 3 limbs, compared with 29% in class 2 limbs, whereas the incidence of superficial venous reflux did not differ among the symptomatic limbs. Isolated superficial femoral and popliteal vein reflux was uncommon, even in class 3 limbs, but combined superficial femoral and popliteal vein reflux was found in 53% of class 3 limbs, compared with 18.5% of class 2 limbs. CONCLUSIONS: Reflux in the deep venous system plays a significant role in the progression of chronic venous insufficiency. Deep system reflux increases as clinical changes become more severe, with significant axial reflux contributing to ulcer formation.

Analysis of Variance↗
PubMed1996

Clinical results of common strategies used to revise infrainguinal vein grafts.

PURPOSE: Patients who have failing infrainguinal bypass grafts or failed grafts reopened with lytic therapy represent a group at high risk of subsequent failure. Previous studies suggest that vein patch angioplasty and jump grafting may be less durable than interposition grafting as a method of correcting graft lesions. Our objective was to assess the value of various technical strategies for graft revision in a series of autogenous infrainguinal bypass grafts and to assess how these variables might affect cumulative graft patency (CGP) rates. METHODS: We retrospectively reviewed the clinical course, anatomic sites of revision, and type of revision performed on 67 grafts in 58 patients who underwent at least one revision from 1991 to 1995. Results were assessed with regression analysis and Kaplan-Meier estimates of CGP rates (p < 0.05 was considered significant). RESULTS: Sixty-seven vein grafts underwent revision of 112 anatomical sites in 95 operations. Forty-nine of 67 grafts were single-segment greater saphenous vein grafts and 18 were composite (> 1 segment) grafts, with an overall 5-year CGP rate of 72%. No difference was observed between the 4-year CGP rate in grafts with hemodynamically significant distal anastomotic stenoses repaired primarily with jump grafts (n = 20, 71% CGP rate) and those with stenoses found only in the graft body (n = 41, 89% CGP rate). Vein patch angioplasty was used primarily, but not exclusively, for focal graft body stenoses (n = 35), whereas interposition grafts (n = 11) were reserved for more diffuse strictures; no significant difference in 3-year CGP rates was observed (94% and 73%, respectively). CONCLUSION: Using an appropriate revision strategy that favors vein patch angioplasty for graft body lesions and jump grafts for distal anastomotic lesions, acceptable assisted patency rates can be achieved in grafts that are at risk for repeated failure.

Angioplasty↗
PubMed1996

Management of recurrent carotid stenosis: should asymptomatic lesions be treated surgically?

PURPOSE: The purpose of this study was to determine factors that may influence patient selection for surgery in recurrent carotid stenosis (RCS) and to contrast the results of primary and secondary carotid endarterectomy (CENDX) with regard to operative morbidity and stroke prevention. METHODS: Forty-eight patients who underwent CENDX for RCS (RCS-OP group) were compared with a contemporaneous group of 40 patients who on at least one post-CENDX duplex ultrasonography study had a greater than 50% stenosis but did not undergo operation (RCS-NO-OP group). This latter group was drawn from 1053 follow-up duplex studies in 348 patients who underwent primary CENDX between the years 1983 and 1993. Each of these two groups was compared with a metanalysis of six key series derived from the literature. RESULTS: No significant differences were seen in the demographics or the incidence of risk factors between the two groups except for a higher incidence of coronary artery disease (p < 0.03) and peripheral vascular disease (p < 0.001) in the RCS-OP group. The operation-specific stroke rate was 2.1%, and the 30-day mortality was also 2.1%. Symptomatic RCS was the indication in 56% of cases. Important anatomic differences were found between groups. The duplex/arteriographic degree of stenosis was greater than 90% in 75% of the patients in the RCS-OP group, whereas only 10% of the patients in the RCS-NO-OP group had greater than 80% stenosis, most being in the 50% to 80% range. An unexpected finding was the sudden progression to occlusion in 10 (25%) of 40 in the RCS-NO-OP group, with 2 (5%) of 10 of the occlusions presenting as unheralded strokes. Overall, a stroke without an antecedent transient ischemic attack occurred in 3 (7.5%) of 40 of patients in the RCS-NO-OP group, all in patients with greater than 75% stenosis on their last documented scan preceding the stroke. CONCLUSION: Given the relatively low stroke rate with surgery in the RCS-OP group (2.1%) and the higher incidence of unheralded strokes (7.5%) in the RCS-NO-OP group, a more aggressive approach may be warranted in patients with asymptomatic high-grade (> 75%) RCS, a strategy not unlike that adopted for primary CENDX.

Aged↗
PubMed1996

Evaluation of carotid artery stenosis: is duplex ultrasonography sufficient?

PURPOSE: The purpose of this study was to compare the results of duplex ultrasonography and magnetic resonance angiography in the evaluation of carotid artery stenosis to determine whether ultrasonography alone is sufficient for preoperative evaluation. METHODS: This study consisted of a retrospective review of 33 patients who underwent 35 carotid endarterectomies. A total of 66 vessels were studied by both duplex ultrasonography and magnetic resonance angiography, and an overall correlation between the two studies was determined. RESULTS: A high correlation was found between duplex and magnetic resonance angiography with an r coefficient equal to 0.87 (Pearson's correlation coefficient) and kappa = 0.75. Discrepancies between the two studies or the presence of intracranial disease did not alter surgical decision making. CONCLUSION: Duplex ultrasonography alone can accurately determine the degree of internal carotid artery stenosis and when paired with careful clinical evaluation is a reliable and cost-effective method for evaluating surgical carotid disease.

Aged↗
PubMed1996

Simultaneous carotid endarterectomy and coronary bypass: perioperative risk and long-term survival.

PURPOSE: The purpose of this article is to examine the outcome of simultaneous coronary bypass-carotid endarterectomy (CABG-CEA) and to compare it with the outcome of endarterectomy alone (CEA alone) in patients at high cardiac risk. METHODS: A retrospective review of the records and follow-up data for 100 consecutive patients who had undergone CABG-CEA and were at high risk and 114 patients who had undergone CEA, had overt coronary artery disease (angina, previous infarct, or ischemic electrocardiographic abnormalities), but had not undergone CABG was carried out. RESULTS: Our CABG-CEA group had a high incidence of symptomatic carotid disease (57%) and contralateral occlusion (28%) when compared with patients in other reports. Patients in the CABG-CEA group were older (67.9 +/- 8.3 years vs 63.6 +/- 15.7 years, p = 0.01) and more often smokers (81% vs 52.6%, p = 0.01) than patients in the CEA alone group. Perioperative mortality was 8% for the CEA-CABG group and for 1.8% for the CEA alone group (p = 0.035). Perioperative stroke morbidity was 9% for the CEA-CABG group and 2.6% for the CEA alone group (p = 0.05). Life table survival at 1,3, and 5 years was 90%, 82%, and 73% versus 96%, 84%, and 76% for the CABG-CEA and CEA alone groups, respectively (p = 0.30). CONCLUSIONS: Selection criteria for CABG-CEA greatly influence perioperative risk. Despite the greater age and more advanced coronary artery disease in the CABG-CEA group, long-term outcome differences are accounted for entirely by differences in perioperative morbidity and mortality. Prospective trials of strategies such as staged CEA and CABG to reduce perioperative risk are needed.

Age Factors↗
PubMed1996

Differential-display polymerase chain reaction identifies nucleophosmin as an estrogen-regulated gene in human vascular smooth muscle cells.

PURPOSE: Atheroprotective effects of estrogen (E2) are well documented and are due in part to direct effects of E2 on vascular cells. We recently demonstrated that human vascular smooth muscle cells (VSMCs) express a functional E2 receptor capable of activatine gene expression. This study was designed to identify E2-regulated genes in human VSMCs. METHODS: VSMC mRNA was screened by differential-display polymerase chain reaction (ddPCR) to identify E2-regulated genes. Quiescent human VSMCs were stimulated with 10% fetal bovine serum in the absence or presence of 10(-8) mol/L E2, and total cellular RNA was harvested. ddPCR was performed in triplicate on each RNA sample and differentially expressed candidate genes were isolated. Differential expression of candidate genes were confirmed by dot blotting and positive bands were identified by sequence analysis. E2-mediated regulation at the protein level was investigated by immunoblotting. RESULTS: ddPCR of RNA harvested from aortic VSMCs identified a 462 bp gene product, EAo8, as a candidate E2- regulated gene. Dot blotting with probes derived from four independent VSMC cultures demonstrated a 5.8 +/- 3.9-fold increase in EAo8 expression in response to E2 treatment (p < 0.05 vs control). Sequence analysis identified EAo8 as nucleophosmin, a nucleolar phosphprotein implicated in the regulation of cell growth and protein synthesis. E2-induced expression of nucleophosmin protein was demonstrated by immunoblotting in both saphenous vein and mammary artery VSMCs. CONCLUSIONS: E2 induces nucleophosmin expression in human VSMCs, and ddPCR is a useful approach for studying estrogen-regulated gene expression in VSMCs.

Cells, Cultured↗
PubMed1996

Duplex-derived valve closure times fail to correlate with reflux flow volumes in patients with chronic venous insufficiency.

The best way to quantitate venous reflux is still a matter of debate. Duplex-derived valve closure time (VCTs) have been used recently because they can be measured easily. We examined the relationships between VCT and duplex-obtained quantitation of venous volume and between VCT and air plethysmography (APG). Sixty-nine legs in 45 patients with varying clinical degrees of chronic venous insufficiency were studied by duplex scan and APG. VCTs were compared with duplex-derived flow calculations and with APG-derived venous filling index and residual volume fraction. The patient's mean age was 47.5 +/- 13.9 years; the mean duration of their symptoms was 13 +/- 4 years. Twenty percent had a history of deep venous thrombosis, and 29% had undergone venous surgery. No correlation was found between VCT and flow volume or between VCT and flow at peak reflux at any of the anatomic locations studied: saphenofemoral junction, greater saphenous vein, lesser saphenous vein, superficial femoral vein, profunda femoris vein, and popliteal vein. Likewise, no correlation was found between total VCT and APG-derived venous filling index or between total flow volumes and APG-derived residual volume fraction. Total VCT and total flow volumes did, however, have a moderate correlation (r = 0.65; p = 0.0003). Duplex-derived VCTs, although extremely useful in determining the presence of reflux, do not correlate with the magnitude of reflux, and should not be used to quantitate the degree of reflux.

Air↗