Doppler ultrasound venous mapping of the lower limbs

A snapshot of venous ultrasound examinations in Australia and New Zealand: Implications for diagnosis and management of chronic venous disease interventions

OBJECTIVE

Chronic venous disease is a common vascular condition, affecting up to 60% of the population worldwide. In Australia and New Zealand, chronic venous insufficiency ultrasound examinations are primarily performed by sonographers. This research aimed to explore how ultrasound examinations are being performed, providing insights into current practices and recommendations for quality improvement.

METHOD

A questionnaire was distributed to capture demographics, practices of ultrasound, examination techniques, the use of nomenclature and experience of the respondents.

RESULTS

The analysis of 97 responses showed a heterogeneity in the clinical application of ultrasound. Most sonographers performed less than two scans per day within 30-45 minutes. Deep venous incompetence was routinely excluded by all respondents. The majority used standing, sitting and reverse Trendelenburg position except for a few using supine position. Manual augmentation was the preferred provocation manoeuvre. Anatomical variations at the junctional level were not adequately evaluated. Although Giacomini's vein was assessed by 80%, 57% of those did not evaluate paradoxical reflux. Seventy-five per cent routinely assessed non-saphenous reflux; however, over 50% were unfamiliar with lymph node venous networks. A significant number of out-dated venous terms were still being used. A low participation rate in continuing professional development was identified, which might be attributable to limited education and training programs.

CONCLUSION

The study is a multi-faceted exploration that identified a need for standardized diagnostic and reporting guidelines. Our results could explain discrepancies in diagnostic findings and inconsistencies in the use of medical terminology, with implications for clinical decision making and assessment of surgical outcome.

The Application of MEVEC 3D Doppler Ultrasound Technique for a New Classification of Morpho-Functional Phenotypes in Lower Limbs Venous Diseases

Introduction

MEVEC 2.1 is a novel 3D mapping software dedicated to the evaluation of the venous vascular three of the lower limbs. It has already proven as a sensitive, specific, and accurate technique able to provide better morphologic and functional details of the lower limb venous system than standard reports. The aim of this study was to identify specific morpho-functional graphic phenotypes in lower limb venous diseases by means of MEVEC 2.1.

Materials

Three-hundred eleven consecutive outpatients underwent lower limb Doppler ultrasound examination by means of the MEVEC 2.1 technique. All of them showed at least one among these pathological findings: venous insufficiency, thrombosis, incompressibility, and/or incompetent.

Results

We tried to evaluate possible clusters among the different morpho-functional findings from the venous maps in order to outline reproducible phenotypes. Correlation indexes allowed us to provide a classification in morpho-functional phenotypes in order to standardize the data from examinations performed by different physicians. Twelve phenotypes had been proposed.

Conclusion

The study showed that the MEVEC 2.1 technique provides a standardized classification that allows physicians identifying phenotypes yielded by 3D mapping of the veins of the lower limbs.

Effect of a Soft Robotic Sock Device on Lower Extremity Rehabilitation Following Stroke: A Preliminary Clinical Study With Focus on Deep Vein Thrombosis Prevention

BACKGROUND AND OBJECTIVE

Immobility of the lower extremity due to medical conditions such as stroke can lead to medical complications such as deep vein thrombosis or ankle contracture, and thereafter prolonged recovery process of the patients. In this preliminary clinical study, we aimed to examine the effect of a novel soft robotic sock device, capable of providing assisted ankle exercise, in improving blood flow in the lower limb to prevent the complication of strokes such as deep vein thrombosis and joint contracture.

METHODS

Stroke patients were recruited (n = 17) to compare patients using the conventional pneumatic compression device with our robotic sock device on separate days. The primary outcome was to compare the venous flow profile of the superficial femoral vein in terms of the time average mean velocity and volumetric flow. The secondary outcome was to identify the ankle joint range of motion with the assistance of the device.

RESULTS

We noted improvements in the venous profile at the early phase of the device use, though its efficacy seemed to drop with time, as compared to the IPC device, where there was a significant improvement in the venous profile. The ankle joint dorsiflexion-plantarflexion range of motion assisted by the device was 11.5±6.3°. Conclusion and clinical impact: The current version of our sock device appears to be capable of improving venous blood flow in the early phase of device use and assisting with ankle joint exercise. The insights from this preliminary clinical study will serve as the basis for further improvement of the device and subsequent conduct of a longitudinal clinical trial.

FUNDING

National Health Innovation Centre Singapore (NHIC) grant, R-172-000-391-511, MOE AcRF Tier 1 R-397-000-301-114.

Efficacy of Preoperative Color Doppler Sonography of Lower Extremity Veins on Postoperative Outcomes in Candidates of Saphenectomy: A Randomized Clinical Trial

BACKGROUND

Doppler sonography is a type of sonography used for imaging the blood flow in the vessels and heart. This technique uses ultrasound waves with high frequency. In some patient candidates for venous graft, the identification of the suitable vein is not possible with clinical examination.

OBJECTIVE

This study compared the effects of preoperative color Doppler sonography of lower extremity veins on the postoperative outcomes of saphenectomy.

METHODS

This randomized clinical trial was conducted on 100 candidates of an off-pump coronary artery bypass graft (CABG) hospitalized in Afshar Hospital in Yazd in 2015. Patients were divided into two groups: 50 patients in the study group and 50 patients in the control group. Patients in the study group underwent color Doppler sonography of lower extremity veins using the Medison 8000 Live device. Patients in the control group were assessed preoperatively by routine venous examination without undergoing color Doppler sonography. The prepping and draping methods and also the preoperative antibiotics were the same for both groups. The patients were assessed for wound infection, edema, hematoma, and DVT 2 days, 1 week, and 1 month after surgery. Data were analyzed by SPSS version 16 using t-test, Chi-square, and Fisher's exact test.

RESULTS

The length of incision for saphenectomy was 29.20 ± 3.71 cm in the Doppler group and 28.98 ± 3.72 cm in the non-Doppler group with no significant difference between the two groups (p=0.768). The two groups were not significantly different with respect to age, gender, diabetes, hypertension, hyperlipidemia, smoking, and history of peripheral vessels disease, postoperative infection, postoperative organ edema, postoperative hematoma, and postoperative DVT.

CONCLUSION

Preoperative color Doppler sonography of the saphenous vein before saphenectomy has no effect on reducing the postoperative complications, and saphenectomy on the basis of intraoperative examination of the vein course by the surgeon has acceptable consequences.

CLINICAL TRIAL REGISTRATION

The trial was registered at the Thai Clinical Trials Registry (TCTR) (http://www.clinicaltrials.in.th) with the TCTR ID: TCTR20160708001.

FUNDING

The authors received no financial support for the research, authorship, and/or publication of this article.

A System for Simple Real-Time Anastomotic Failure Detection and Wireless Blood Flow Monitoring in the Lower Limbs

Current totally implantable wireless blood flow monitors are large and cannot operate alongside nearby monitors. To alleviate the problems with the current monitors, we developed a system to monitor blood flow wirelessly, with a simple and easily interpretable real-time output. To the best of our knowledge, the implanted electronics are the smallest in reported literature, which reduces bio-burden. Calibration was performed across realistic physiological flow ranges using a syringe pump. The device's sensors connected directly to the bilateral femoral veins of swine. For each 1 min, blood flow was monitored, then, an occlusion was introduced, and then, the occlusion was removed to resume flow. Each vein of four pigs was monitored four times, totaling 32 data collections. The implant measured 1.70 cm3 without battery/encapsulation. Across its calibrated range, including equipment tolerances, the relative error is less than ±5% above 8 mL/min and between -0.8% and +1.2% at its largest calibrated flow rate, which to the best of our knowledge is the lowest reported in the literature across the measured calibration range. The average standard deviation of the flow waveform amplitude was three times greater than that of no-flow. Establishing the relative amplitude for the flow and no-flow waveforms was found necessary, particularly for noise modulated Doppler signals. Its size and accuracy, compared with other microcontroller-equipped totally implantable monitors, make it a good candidate for future tether-free free flap monitoring studies.

Review of the cost of venous thromboembolism

Background

Venous thromboembolism (VTE) is the second most common medical complication and a cause of excess length of hospital stay. Its incidence and economic burden are expected to increase as the population ages. We reviewed the recent literature to provide updated cost estimates on VTE management.

Methods

Literature search strategies were performed in PubMed, Embase, Cochrane Collaboration, Health Economic Evaluations Database, EconLit, and International Pharmaceutical Abstracts from 2003–2014. Additional studies were identified through searching bibliographies of related publications.

Results

Eighteen studies were identified and are summarized in this review; of these, 13 reported data from the USA, four from Europe, and one from Canada. Three main cost estimations were identified: cost per VTE hospitalization or per VTE readmission; cost for VTE management, usually reported annually or during a specific period; and annual all-cause costs in patients with VTE, which included the treatment of complications and comorbidities. Cost estimates per VTE hospitalization were generally similar across the US studies, with a trend toward an increase over time. Cost per pulmonary embolism hospitalization increased from $5,198–$6,928 in 2000 to $8,764 in 2010. Readmission for recurrent VTE was generally more costly than the initial index event admission. Annual health plan payments for services related to VTE also increased from $10,804–$16,644 during the 1998–2004 period to an estimated average of $15,123 for a VTE event from 2008 to 2011. Lower costs for VTE hospitalizations and annualized all-cause costs were estimated in European countries and Canada.

Conclusion

Costs for VTE treatment are considerable and increasing faster than general inflation for medical care services, with hospitalization costs being the primary cost driver. Readmissions for VTE are generally more costly than the initial VTE admission. Further studies evaluating the economic impact of new treatment options such as the non-vitamin K antagonist oral anticoagulants on VTE treatment are warranted.

A comparison of the efficacy and cost of different venous leg ulcer dressings: a retrospective cohort study

Objective. To compare the efficacy and cost-effectiveness of simple nonadherent dressings with other more expensive dressing types in the treatment of venous leg ulcers. Study Design. Retrospective cohort study. Location. The leg ulcer clinic at the University Hospital of South Manchester. Subjects and Methods. The healing rates of twelve leg ulcer patients treated with simple nonadherent dressings (e.g., NA Ultra) were compared with an equal number of patients treated with modern dressings to determine differences in healing rates and cost. Main Outcome Measures. Rate of healing as determined by reduction in ulcer area over a specified period of time and total cost of dressing per patient. Results. Simple nonadherent dressings had a mean healing rate of 0.353 cm(2)/week (standard deviation ± 0.319) compared with a mean of 0.415 cm(2)/week (standard deviation ± 0.383) for more expensive dressings. This resulted in a one-tailed p value of 0.251 and a two-tailed p value of 0.508. Multiple regression analysis gave a significance F of 0.8134. Conclusion. The results indicate that the difference in healing rate between simple and modern dressings is not statistically significant. Therefore, the cost of dressing type should be an important factor influencing dressing selection.

A three-dimensional electronic report of a venous echo color Doppler of the lower limbs: MEVeC®

BACKGROUND

The reports of ultrasound evaluation of lower limb veins are difficult to understand by general practitioners (GPs) and physicians who are not specialized. We developed software for a three-dimensional (3D) electronic report of venous hemodynamic mapping (MEVeC(®)) in order to represent lower limb venous vasculature in a 3D way. The aim of the study is to compare the novel 3D report with the standard report.

METHODS

Thirty subjects (medical students and GPs) evaluated a standard report and a novel 3D report of the lower limb veins of a prespecified patient. The cases were randomly and blindly taken from an archive of 100 cases. GPs and students answered a questionnaire made up of 13 questions that were structured in order to investigate the readability and comprehension of the two reports. A score ranging from 0 to 10 (0= not understandable; 10= full comprehension) was attributed to each report for each question according to the readability of the venous scheme proposed.

RESULTS

The scores from each question of the questionnaire were compared. The 3D report (MEVeC(®)) obtained higher scores than those from the evaluation of the standard report (P<0.0001). Each question revealed the superiority of the 3D report (MEVeC(®)) as compared with the standard report of the ultrasound evaluation of lower limbs. When dividing the scores according to percentiles, the 3D report (MEVeC(®)) still continued to show more readability than the standard report in a statistically significant way (P<0.0001).

CONCLUSION

The new 3D report (MEVeC(®)) concerning ultrasound evaluation of lower limb veins is more reproducible than the standard report when evaluated by medical physicians not specialized in the evaluation of the vein tree of lower limbs.