Lymphatic transport in patients with chronic venous insufficiency and venous leg ulcers following sequential pneumatic compression

Case Report: The effect of automated manual lymphatic drainage therapy on lymphatic contractility in 4 distinct cases

Introduction

Automated manual lymphatic drainage therapy (AMLDT) is available for home use in the form of a pneumatic mat of 16 pressurized air channels that inflate and deflate to mimic the stretch and release action of manual lymphatic drainage therapy. Four cases (a patient with complex regional pain syndrome and lymphedema, a healthy patient, a breast cancer survivor with chronic pain, and a patient with a history of abdominal surgery) underwent near-infrared fluorescence lymphatic imaging (NIRFLI) with AMLDT to evaluate the effect of AMLDT on lymphatic pumping and pain.

Methods

Each patient received 32-36 injections of 25 μg indocyanine green (ICG) on the anterior and posterior sides of their body and underwent 1 h of NIRFLI to assess the drainage of ICG laden lymph toward regional nodal basins at baseline. Each patient lay supine on the mat for 1 h of AMLDT with NIRFLI to assess lymphatic flow during treatment. A final NIFRFLI assessment was done 30-60 min posttreatment with the patient in the supine and prone position. Patients reported baseline and posttreatment pain using the Visual Analogue Scale. An imager analyzed NIRFLI images using ImageJ (US National Institutes of Health). Using time stamps of the first and last images to determine time lapsed and the number of pulses observed in a timeframe, pulsing frequency (pulses/min) was obtained to assess lymphatic function.

Results

All 4 cases completed the NIRFLI and AMLDT without complications; all 3 patients with baseline pain reported reduced pain posttreatment. AMLDT appeared to alter lymphatic contractility, with both increased and decreased pulsing frequencies observed, including in nonaffected limbs. Pulsing frequencies were very heterogeneous among patients and varied within anatomic regions of the same patient.

Discussion

This proof-of-concept study suggests that AMLDT may impact lymphatic contractility. Further research on its effect on lymphatic function is warranted.

Impact of lymphedema in the management of venous leg ulcers

INTRODUCTION

Lymphedema (LED) in patients with venous leg ulcers (VLU) [VLU+LED] can impair ulcer healing and predispose to cellulitis. There is little data, however, demonstrating how lymphatic dysfunction may impact the clinical course, treatment, and healthcare expenditures for VLU+LED versus VLU-LED patients.

OBJECTIVE

To determine how lymphatic dysfunction might influence treatment and expenditures among VLU patients in a large deidentified healthcare claims database.

METHODS

A retrospective cohort design and data from the IBM MarketScan Database (April 2013 to March 2019) were employed. Study population comprised VLU patients, and was stratified into two subgroups: VLU+LED (index date = date of first LED diagnosis) and VLU-LED (index dates randomly assigned to match distribution of index dates for VLU+LED). Within each subgroup, patients with <1 year of healthcare claims information before and after their index dates were excluded. Demographics, comorbidities, procedures/treatments, as well as all-cause post-index medical resource utilization and expenditures ($/patient/year) of the two groups were compared. Stabilized inverse probability treatment weights (IPTWs) were employed to adjust for differences between groups in baseline characteristics.

RESULTS

A total of 5466 VLU patients were identified (VLU+LED: N = 299; VLU-LED: N = 5167). Overall ambulatory encounters (AMB ENC) and their components were higher in VLU+LED, which were reflected in increased expenditures for this group (Table 1). Treatment with endovenous ablation (EVA) or stenting for venous hypertension as well as for specific measures for LED were higher in the 1-year post-index period for VLU+LED. The use of LED specific therapy was low for both groups, but a greater percentage of VLU+LED patients received therapy, which was predominantly manual lymphatic drainage (17.4%) rather than pneumatic compression (10.7%).

CONCLUSIONS

The clinical presence of LED in patients with VLU is a marker for a more complex disease process with more episodes of cellulitis and expenditures, but a surprisingly low specific treatment for LED.

Compression therapy in peripheral artery disease: a literature review

OBJECTIVE

Our objective is to examine the pathophysiology of oedema in the ischaemic and post-revascularised limb, compare compression stockings to pneumatic compression devices, and summarise compression regimens in patients with severe peripheral artery disease (PAD) without revascularisation, after revascularisation, and in mixed arterial and venous disease.

METHOD

A scoping literature review of the aforementioned topics was carried out using PubMed.

RESULTS

Compression therapy has been shown to increase blood flow and aid in wound healing through a variety of mechanisms. Several studies suggest that intermittent pneumatic compression (IPC) devices can be used to treat critical limb ischaemia in patients without surgical options. Additionally, compression stockings may have a role in preventing oedema after peripheral artery bypass surgery, thereby diminishing pain and reducing the risk of surgical wound dehiscence.

CONCLUSION

Oedema may occur in the ischaemic limb after revascularisation surgery, as well as in combination with venous disease. Clinicians should not fear using compression therapy in PAD.

Imaging peripheral lymphatic dysfunction in chronic conditions

The lymphatics play important roles in chronic diseases/conditions that comprise the bulk of healthcare worldwide. Yet the ability to routinely image and diagnose lymphatic dysfunction, using commonly available clinical imaging modalities, has been lacking and as a result, the development of effective treatment strategies suffers. Nearly two decades ago, investigational near-infrared fluorescence lymphatic imaging and ICG lymphography were developed as routine diagnostic for clinically evaluating, quantifying, and treating lymphatic dysfunction in cancer-related and primary lymphedema, chronic venous disease, and more recently, autoimmune and neurodegenerative disorders. In this review, we provide an overview of what these non-invasive technologies have taught us about lymphatic (dys) function and anatomy in human studies and in corollary animal studies of human disease. We summarize by commenting on new impactful clinical frontiers in lymphatic science that remain to be facilitated by imaging.

A new compression system for treatment of venous leg ulcers: a prospective, single-arm, clinical trial (FREEDOM)

OBJECTIVE

To evaluate the efficacy, tolerability and acceptability of a new multicomponent compression system in one bandage for the local treatment of patients with venous leg ulcers (VLUs).

METHOD

This was an international, prospective, non-comparative, clinical trial, conducted in France and Germany. Eligible participants had a VLU with a wound area of 2-20cm², lasting for a maximum of 24 months. For a period of 6 weeks, patients were treated with a new multicomponent compression system in one bandage which was worn day and night, providing high working pressure and moderate resting pressure (UrgoK1). Clinical assessments, wound measurement and photographs were planned at weeks 1, 2, 4 and 6. The primary endpoint was the relative wound area reduction (RWAR) after 6 weeks of treatment. Secondary endpoints included wound closure rate, oedema resolution, change in patient's health-related quality of life (HRQoL), acceptability, adherence to the compression therapy, local tolerance, and physician's overall satisfaction with the evaluated compression system.

RESULTS

A cohort of 52 patients (52% female, mean age 75.4±13.0 years) with VLUs, including oedema in 58% of cases, were recruited from 22 centres. At baseline, 42 patients had already been treated with a different compression system. VLUs had been present for 5.6±4.9 months and had a mean area of 5.7±4.3cm². After 6 weeks of treatment, a median RWAR of 91% (interquartile range: 39.4; 100.0) was achieved. Wound closure was reported in 35% of patients. A RWAR ≥40% at week 4, predictive of wound healing at 12 weeks, was achieved in 62% of patients. At the final visit, oedema present at baseline was resolved in 57% of patients. Substantial improvements in the HRQoL of the patients were reported with a decrease of the pain/discomfort and anxiety/depression dimensions. Comfort in wearing the evaluated system was reported as 'very good' or 'good' by 79% of patients, resulting in a high patient adherence to compression therapy. Compared to previous compression systems, half of the patients reported more ease in wearing shoes, and greater satisfaction and comfort with this new system. Nine non-serious adverse events related to the device or its procedure occurred in seven patients. At the final visit, the majority of the physicians were 'very satisfied' or 'satisfied' with the new compression system overall.

CONCLUSION

The new multicomponent compression system in one bandage has been shown to promote rapid healing of VLUs, reduce oedema, improve HRQoL and to be well tolerated and accepted. It appears to be a viable alternative to existing compression systems.

Lymphatic function and anatomy in early stages of lipedema

OBJECTIVE

Lipedema is an inflammatory subcutaneous adipose tissue disease that develops in women and may progress to lipolymphedema, a condition similar to lymphedema, in which lymphatic dysfunction results in irresolvable edema. Because it has been shown that dilated lymphatic vessels, impaired pumping, and dermal backflow are associated with presymptomatic, cancer-acquired lymphedema, this study sought to understand whether these abnormal lymphatic characteristics also characterize early stages of lipedema prior to lipolymphedema development.

METHODS

In a pilot study of 20 individuals with Stage I or II lipedema who had not progressed to lipolymphedema, lymphatic vessel anatomy and function in upper and lower extremities were assessed by near-infrared fluorescence lymphatic imaging and compared with that of a control population of similar age and BMI.

RESULTS

These studies showed that, although lower extremity lymphatic vessels were dilated and showed intravascular pooling, the propulsion rates significantly exceeded those of control individuals. Upper extremity lymphatics of individuals with lipedema were unremarkable. In contrast to individuals with lymphedema, individuals with Stage I and II lipedema did not exhibit dermal backflow.

CONCLUSIONS

These results suggest that, despite the confusion in the diagnoses between lymphedema and lipedema, their etiologies differ, with lipedema associated with lymphatic vessel dilation but not lymphatic dysfunction.

Host-guest interactions of indocyanine green with β-cyclodextrin permit real-time characterization of the rat lymphatic system

Objective

Fluorescence contrast technology using indocyanine green (ICG) could be useful for the rapid, dynamic, and objective assessment of blood vessels and the surrounding tissues when combined with near-infrared (NIR) imaging. Although ICG is a clinically available NIR fluorescence imaging probe, it can easily aggregate and is, thus, unstable. In the present study, we examined the efficacy of a host–guest ICG–β-cyclodextrin (CD) complex, which is used in pharmaceutics to improve the water solubility, stability, and bioavailability of hydrophobic molecules, for NIR imaging after hind footpad administration in a rat model.

Methods

To verify the performance of the ICG-β-CD complex with the host–guest self-assembly method in vivo, we performed simultaneous small animal (IVIS Spectrum system; PerkinElmer, Waltham, MA) and clinical (DIGI-MIH-001 near-infrared fluorescence imaging system; Beijing Digital Precision Medical Technology Co, Ltd, Beijing, China) imaging and evaluated the fluorescent properties of the ICG-β-CD complex in the hind footpad model of Sprague-Dawley male rats.

Results

We successfully prepared the ICG-β-CD complex. Compared with ICG, in vivo experiments showed that this complex had reduced absorbance at 710 nm and increased absorbance at 780 nm, indicating that it could prevent the dimeric aggregation of ICG, and a significantly higher fluorescence intensity at 730 nm excitation. After injection of 1.25 mg/mL of ICG or ICG-β-CD complex solutions into the rat hind footpad, fluorescent NIR lymphatic images were observed with both imaging systems. During the 12-hour observation period, the signal background ratio of ICG-β-CD showed a greater acute increase and a higher signal background ratio compared with ICG. The signal background ratio of ICG-β-CD was 125 to 100 from 260 to 540 minutes. These in vivo data suggest that ICG-β-CD has greater diffusion from the injection site and faster transport to the lymphatic system compared with ICG.

Conclusions

ICG-β-CD showed faster lymphatic transport than ICG, allowing for more rapid lymphatic NIR imaging. Thus, the ICG-β-CD complex might be a promising fluorescent agent for clinical lymphatic NIR imaging.

The lymphatic system plays a crucial role in maintaining tissue fluid homeostasis by draining protein-rich fluid from the perivascular interstitial spaces back into the circulation. The lymphatic system also plays a variety of roles in the progression of some peripheral vascular diseases, including venous leg ulcers, atherosclerotic vascular disease, and severe foot infection. Understanding the dynamic changes of the lymphatic fluid is indispensable for a variety of clinical situations and research areas. We investigated the potential feasibility of the indocyanine green–β-cyclodextrin complex in clinical applications using clinically available near-infrared fluorescence imaging equipment.

The American Venous Forum, American Vein and Lymphatic Society and the Society for Vascular Medicine expert opinion consensus on lymphedema diagnosis and treatment

BACKGROUND

Lymphedema imposes a significant economic and social burden in modern societies. Controversies about its risk factors, diagnosis, and treatment permeate the literature. The goal of this study was to assess experts' opinions on the available literature on lymphedema while following the Delphi methodology.

METHODS

In December of 2019, the American Venous Forum created a working group tasked to develop a consensus statement regarding current practices for the diagnosis and treatment of lymphedema. A panel of experts was identified by the working group. The working group then compiled a list of clinical questions, risk factors, diagnosis and evaluation, and treatment of lymphedema. Fifteen questions that met the criteria for consensus were included in the list. Using a modified Delphi methodology, six questions that received between 60% and 80% of the votes were included in the list for the second round of analysis. Consensus was reached whenever >70% agreement was achieved.

RESULTS

The panel of experts reached consensus that cancer, infection, chronic venous disease, and surgery are risk factors for secondary lymphedema. Consensus was also reached that clinical examination is adequate for diagnosing lymphedema and that all patients with chronic venous insufficiency (C3-C6) should be treated as lymphedema patients. No consensus was reached regarding routine clinical practice use of radionuclide lymphoscintigraphy as a mandatory diagnostic tool. However, the panel came to consensus regarding the importance of quantifying edema in all patients (93.6% in favor). In terms of treatment, consensus was reached favoring the regular use of compression garments to reduce lymphedema progression (89.4% in favor, 10.6% against; mean score of 79), but the use of Velcro devices as the first line of compression therapy did not reach consensus (59.6% in favor vs 40.4% against; total score of 15). There was agreement that sequential pneumatic compression should be considered as adjuvant therapy in the maintenance phase of treatment (91.5% in favor vs. 8.5% against; mean score of 85), but less so in its initial phases (61.7% in favor vs. 38.3% against; mean score of 27). Most of the panel agreed that manual lymphatic drainage should be a mandatory treatment modality (70.2% in favor), but the panel was split in half regarding the proposal that reductive surgery should be considered for patients with failed conservative treatment.

CONCLUSION

This consensus process demonstrated that lymphedema experts agree on the majority of the statements related to risk factors for lymphedema, and the diagnostic workup for lymphedema patients. Less agreement was demonstrated on statements related to treatment of lymphedema. This consensus suggests that variability in lymphedema care is high even among the experts. Developers of future practice guidelines for lymphedema should consider this information, especially in cases of low-level evidence that supports practice patterns with which the majority of experts disagree.

Exploring disease interrelationships in patients with lymphatic disorders: A single center retrospective experience

BACKGROUND

The lymphatic contribution to the circulation is of paramount importance in regulating fluid homeostasis, immune cell trafficking/activation and lipid metabolism. In comparison to the blood vasculature, the impact of the lymphatics has been underappreciated, both in health and disease, likely due to a less well-delineated anatomy and function. Emerging data suggest that lymphatic dysfunction can be pivotal in the initiation and development of a variety of diseases across broad organ systems. Understanding the clinical associations between lymphatic dysfunction and non-lymphatic morbidity provides valuable evidence for future investigations and may foster the discovery of novel biomarkers and therapies.

METHODS

We retrospectively analysed the electronic medical records of 724 patients referred to the Stanford Center for Lymphatic and Venous Disorders. Patients with an established lymphatic diagnosis were assigned to groups of secondary lymphoedema, lipoedema or primary lymphovascular disease. Individuals found to have no lymphatic disorder were served as the non-lymphatic controls. The prevalence of comorbid conditions was enumerated. Pairwise co-occurrence pattern analyses, validated by Jaccard similarity tests, was utilised to investigate disease-disease interrelationships.

RESULTS

Comorbidity analyses underscored the expected relationship between the presence of secondary lymphoedema and those diseases that damage the lymphatics. Cardiovascular conditions were common in all lymphatic subgroups. Additionally, statistically significant alteration of disease-disease interrelationships was noted in all three lymphatic categories when compared to the control population.

CONCLUSIONS

The presence or absence of a lymphatic disease significantly influences disease interrelationships in the study cohorts. As a physiologic substrate, the lymphatic circulation may be an underappreciated participant in disease pathogenesis. These relationships warrant further, prospective scrutiny and study.

Imaging biomarkers for diagnosis and treatment response in patients with lymphedema

Lymphedema is defined as a dysfunction of the lymphatic system producing an accumulation of lymphatic fluid in the surrounding tissue, as well as edema and fibrosis. A total of 250 million people worldwide are affected by this condition. Greater than 99% of these cases are related to a secondary cause. As there is a lack of curative therapy, the goal involves early diagnosis, in order to prevent the progression of the disease. Additionally, early diagnosis can aid in decreasing the demand for more complex surgical procedures. Currently, there is an impressive breadth of diagnostic tests available for these patients. We aimed to review the available literature in relation to the utilization of imaging biomarkers for the early diagnosis and treatment response in lymphedema.

Chronic venous disease and diabetic microangiopathy: pathophysiology and commonalities

Chronic venous disease and diabetes mellitus are highly prevalent and debilitating conditions affecting millions of individuals globally. Although these conditions are typically considered as separate entities, they often co-exist which may be important in both understanding their pathophysiology and determining the best treatment strategy. Diabetes mellitus is twice as common in patients with chronic venous disease compared with the general population. Notably, a large proportion of patients with diabetes mellitus present with venous disorders, although this is often overlooked. The etiology of chronic venous disease is multifactorial, involving hemodynamic, genetic, and environmental factors which result in changes to the venous endothelium and structural wall as well as inflammation. Inflammation, endothelial dysfunction and hyperfiltration or leakage, are commonly observed in diabetes mellitus and cause various diabetic microvascular complications. Both diseases are also influenced by the increased expression of adhesion molecules, chemokines, and cytokines, and are characterized by the presence of vessel hypertension. Consequently, despite differences in etiology, the pathophysiology of both chronic venous disease and diabetic microangiopathy appears to be driven by endothelial dysfunction and inflammation. Treatment strategies should take the co-existence of chronic venous disease and diabetic microangiopathy into account. Compression therapy is recommended in inflammatory conditions that have an edema component as seen in both chronic venous disease and diabetes mellitus. Lifestyle changes like weight loss and exercise, will improve metabolic state and lower inflammation and should be promoted in these patients. Additionally, both patient populations may benefit from venoactive drugs.

Lymphatic Contractile Function: A Comprehensive Review of Drug Effects and Potential Clinical Application

BACKGROUND

The lymphatic system and the cardiovascular system work together to maintain body fluid homeostasis. Despite that, the lymphatic system has been relatively neglected as a potential drug target and a source of adverse effects from cardiovascular drugs. Like the heart, the lymphatic vessels undergo phasic contractions to promote lymph flow against a pressure gradient. Dysfunction or failure of the lymphatic pump results in fluid imbalance and tissue oedema. While this can due to drug effects, it is also a feature of breast cancer-associated lymphoedema, chronic venous insufficiency, congestive heart failure and acute systemic inflammation. There are currently no specific drug treatments for lymphatic pump dysfunction in clinical use despite the wealth of data from pre-clinical studies.

AIM

To identify (1) drugs with direct effects on lymphatic tonic and phasic contractions with potential for clinical application, and (2) drugs in current clinical use that have a positive or negative side effect on lymphatic function.

METHODS

We comprehensively reviewed all studies that tested the direct effect of a drug on the contractile function of lymphatic vessels.

RESULTS

Of the 208 drugs identified from 193 studies, about a quarter had only stimulatory effects on lymphatic tone, contraction frequency and/or contraction amplitude. Of FDA-approved drugs, there were 14 that increased lymphatic phasic contractile function. The most frequently used class of drug with inhibitory effects on lymphatic pump function were the calcium channels blockers.

CONCLUSION

This review highlights the opportunity for specific drug treatments of lymphatic dysfunction in various disease states and for avoiding adverse drug effects on lymphatic contractile function.

The economic impact of infection requiring hospitalization on venous leg ulcers

OBJECTIVE

To determine the impact of infection (INF) on medical resource utilization (MRU) and cost of care in patients with venous leg ulcers (VLU).

METHODS

We performed a retrospective case-control study of 78 patients followed for a minimum of 12 months with C₆ VLUs treated by vascular surgeons, at our wound center. To eliminate minor episodes of INF or incorrectly diagnosed episodes, only patients who had an inpatient admission specifically for INF comprised the INF group, whereas all other admissions were excluded for this group. MRU was defined as the number of clinic visits, Visiting Nurse Association (VNA) visits, and inpatient admissions. The actual cost for treatment was determined using financial data provided by both the hospital and physician organization billing units. The total cost over the 1-year follow-up period comprised individual cost centers: inpatient and outpatient facility fees, physician fees, and visiting nurse services. Mean MRU and cost data were compared using the two-sample t-test between INF and NON-INF.

RESULTS

Of the 78 patients with C₆ VLU, 9 (11.5%) had at least one inpatient admission for INF related to their VLU in the 1-year treatment period, with an additional five recurrent admissions for a total of 14 admissions, whereas 69 NON-INF had three NON-INF-related admissions. There was no difference between INF and NON-INF for usual risk factors, but INF had a greater proportion of congestive heart failure (44%; 13%, P < .02). Regarding MRU, both the number of outpatient wound center visits (INF 16.89 ± 6.41; NON-INF 9.46 ± 7.7, P = .008) and VNA blocks (INF 3.89 ± 2.93; NON-INF 1.94 ± 2.24, P < .02) were greater for INF. Total costs for INF ($27,408 ± $10,859) were threefold higher than those for NON-INF ($11,088 ± $9343, P < .0001) and subsequent VNA costs were doubled for INF ($9956 ± $4657) vs NON-INF ($4657 ± $5486, P = .01).

CONCLUSIONS

INFs in patients with VLU led to an overall increase in MRU and cost of care, with the INF cohort requiring more inpatient admissions, outpatient visits, and VNA services than NON-INF. Given the major impact INF has on cost and MRU, better treatment modalities that prevent INF as well as identifying risk factors for INF in patients with VLU are needed.

Degradation of lymphatic anatomy and function in early venous insufficiency

OBJECTIVE

We used near-infrared fluorescence lymphatic imaging in a pilot study to assess the lymphatics in preulcerative (C2-C4) venous insufficiency and determine whether involvement and/or degradation of lymphatic anatomy or function could play a role in the progression of chronic venous insufficiency. We also explored the role of lymphatics in early peripheral arterial disease.

METHODS

After informed consent and intradermal injections of indocyanine green for rapid lymphatic uptake, near-infrared fluorescence lymphatic imaging was used to assess the lymphatic anatomic structure and quantify the lymphatic propulsion rates in subjects with early venous insufficiency. The anatomic observations included interstitial backflow, characterized by the abnormal spreading of indocyanine green from the injection site primarily into the surrounding interstitial tissues; dermal backflow, characterized by the retrograde movement of dye-laden lymph from collecting lymphatics into the lymphatic capillaries; and lymphatic vessel segmentation and dilation.

RESULTS

Ten subjects with venous insufficiency were enrolled, resulting in two legs with C2 disease, nine legs with C3 disease, eight legs with C4 disease, and one leg with C5 disease. Interstitial and/or dermal backflow were observed in 25%, 33%, and 41% of the injection sites in each limb with C2, C3, and C4 disease, respectively. Distinct vessel segmentation and dilation were observed in limbs with a C3 and higher classification, and dermal backflow proximal to the injection sites was observed in two legs with C4 disease and in the inguinal region of the C5 study subject. The overall average lymph propulsion rates were 1.3 ± 0.4, 1.2 ± 0.7, and 0.8 ± 0.5 contractile events/min for limbs with C2, C3, and C4 disease, respectively. One subject with peripheral arterial disease, who had previously undergone bypass surgery, presented with extensive dermal backflow and lymphatic reflux.

CONCLUSIONS

Near-infrared fluorescence lymphatic imaging demonstrated that, compared with normal health subjects, the lymphatic anatomy and contractile function generally degrade with the severity of venous insufficiency. Lymphatic abnormalities mimic those in early cancer-acquired lymphedema subjects, as previously observed by us and others. Additional studies are needed to decipher the relationship, including any causality, between lymphatic dysfunction and peripheral vascular disease and venous insufficiency.

A dual compression system: preliminary clinical insights from the US

There is growing evidence on an interconnection between the venous and lymphatic systems in venous leg ulceration, and the possible effects of prolonged oedema and lymphatic impairment in delayed wound healing. Compression therapy is a widely accepted treatment for venous and lymphatic disorders, as it decreases recurrence rates and prolongs the interval between recurrences. Compression bandages improve venous return, increase the volume and rate of venous flow, reduce oedema and stimulate anti-inflammatory processes. The pressure at the interface (IP) of the bandage and the skin is related to the elastic recoil of the product used and its resistance to expansion. The pressure difference between the IP in the supine and standing positions is called the static stiffness index (SSI). Elastic materials provide little resistance to muscle expansion during physical activity, resulting in small pressure differences between resting and activity, with an SSI <10mmHg. Stiff, inelastic materials with a stretch of <100% resist the increase of muscle volume during physical activity, producing higher peak pressures, an SSI of >10mmHg and a greater haemodynamic benefit than elastic systems. UrgoK2 is a novel dual-layer high-compression system consisting of an inelastic (short stretch) and elastic (long stretch) bandage, resulting in sustained tolerable resting pressure and elevated working pressures over extended wear times. It is indicated for the treatment of active venous leg ulcers and the reduction of chronic venous oedema. Each bandage layer has a visual aid to enable application at the correct pressure level. Published European studies have assessed this compression system, exploring its consistency of application, tolerability and efficacy. This article presents the first reports of health professionals' clinical experience of using the compression system in the US, where it has been recently launched. Initial feedback is promising.

The Development and Treatment of Lymphatic Dysfunction in Cancer Patients and Survivors

Breast-cancer-acquired lymphedema is routinely diagnosed from the appearance of irreversible swelling that occurs as a result of lymphatic dysfunction. Yet in head and neck cancer survivors, lymphatic dysfunction may not always result in clinically overt swelling, but instead contribute to debilitating functional outcomes. In this review, we describe how cancer metastasis, lymph node dissection, and radiation therapy alter lymphatic function, as visualized by near-infrared fluorescence lymphatic imaging. Using custom gallium arsenide (GaAs)-intensified systems capable of detecting trace amounts of indocyanine green administered repeatedly as lymphatic contrast for longitudinal clinical imaging, we show that lymphatic dysfunction occurs with cancer progression and treatment and is an early, sub-clinical indicator of cancer-acquired lymphedema. We show that early treatment of lymphedema can restore lymphatic function in breast cancer and head and neck cancer patients and survivors. The compilation of these studies provides insights to the critical role that the lymphatics and the immune system play in the etiology of lymphedema and associated co-morbidities.

Correlation of disease comorbidity with prescribed treatment among insured U.S. lymphedema patients

OBJECTIVE

The objective of this study was to define the current forms of treatment in a contemporary population of lymphedema (LED) patients for LED related to breast cancer, the most prevalently diagnosed LED comorbidity in Western countries, and phlebolymphedema with venous leg ulcer (PLEDU), a sequela of chronic venous disease. The goals of LED therapy are to reduce edema, thereby improving function and related symptoms, and to improve skin integrity to prevent development of infection. Treatment is generally nonsurgical: conservative care, including complex physical therapy, manual lymphatic drainage, and compression bandaging; or pneumatic compression device (PCD) therapy by a simple nonprogrammable device or an advanced programmable device.

METHODS

To determine the frequency of individual types of treatment for LED and their relationship to breast cancer-related lymphedema (BCRL) and PLEDU, we queried claims from a deidentified Health Insurance Portability and Accountability Act-compliant commercial administrative insurance database with >165 million members. A total of 26,902 patients identified with LED who had been enrolled with continuous medical benefits for 12 months before and after the index date for the complete years 2012 through 2016 were separated into four treatment categories: no treatment, conservative care, simple PCD (SPCD), and advanced PCD. LED treatment was related to the BCRL and PLEDU comorbidities.

RESULTS

BCRL patients, who represented 32.1% of all study patients, made up 41% of all patients receiving conservative care and 24% of patients receiving PCD therapy. By contrast, PLEDU patients (9.6% of study patients) were proportionally under-represented in the conservative care group (7.8%) but composed a disproportionately high share of the PCD therapy group (17.7%). PLEDU patients represented 23.5% of all LED patients prescribed SPCD therapy, whereas BCRL patients composed 10.3% of total LED patient SPCD prescriptions (P < .001).

CONCLUSIONS

Our analysis of a large health care administrative database showed clear differences between the way BCRL and PLEDU patients are treated. Compared with BCRL patients, PLEDU patients were less likely to receive conservative care and more likely to be prescribed SPCDs for pneumatic compression therapy. These differences suggest that lymphatic therapy may be undervalued for treatment of chronic venous swelling and prevention and treatment of PLEDU.

Review of adjustable velcro wrap devices for venous ulceration

Compression therapy is the mainstay of treatment for patients with venous leg ulcers. Current gold standard is 4 layer bandaging, which has a significant impact on patients comfort, ability to wear their own shoes, and quality of life, as well as taking significant time to apply, and losing compression over time. This systematic review aims to evaluate the use of Velcro wrap devices for the treatment of venous ulceration. Preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were used to identify articles reporting the use of Velcro wrap devices in patients with venous ulceration. Sixteen articles were identified (14 case series, 1 randomised trial, and 1 audit) reporting on 192 patients. There were reports of improved time to healing, reduced cost by >50%, reduced number and duration of nursing appointments, and improved quality of life in patients in Velcro wrap devices. Although the evidence remains poor, Velcro devices have potential to improve outcomes for patients with venous ulceration and further good quality studies should be undertaken to evaluate these further.

Head and Neck Lymphedema: Treatment Response to Single and Multiple Sessions of Advanced Pneumatic Compression Therapy

Ten head and neck cancer survivors diagnosed with head and neck lymphedema (HNL) were imaged using near-infrared fluorescence lymphatic imaging (NIRFLI) prior to and immediately after an initial advance pneumatic compression device treatment and again after 2 weeks of daily at-home use. Images assessed the impact of pneumatic compression therapy on lymphatic drainage. Facial composite measurement scores assessed reduction/increase in external swelling, and survey results were obtained. After a single pneumatic compression treatment, NIRFLI showed enhanced lymphatic uptake and drainage in all subjects. After 2 weeks of daily treatment, areas of dermal backflow disappeared or were reduced in 6 of 8 subjects presenting with backflow. In general, reductions in facial composite measurement scores tracked with reductions in backflow and subject-reported improvements; however, studies are needed to determine whether longer treatment durations can be impactful and whether advanced pneumatic compression can be used to ameliorate backflow characteristic of HNL.

Near-infrared fluorescence lymphatic imaging of Klippel-Trénaunay syndrome

The relationship between lymphatic and venous malformations in Klippel-Trénaunay syndrome is difficult to assess. Herein the authors describe near-infrared fluorescence lymphatic imaging to assess the lymphatics of a subject with a large port-wine stain and right leg edema. Although lymphatic vessels in the medial, affected knee appeared dilated and perhaps tortuous, no definitive abnormal lymphatic pooling or propulsion was observed. The lymphatics in the affected limb were well defined but less numerous than in the contralateral limb, and active, contractile function was observed in all vessels. As demonstrated, near-infrared fluorescence lymphatic imaging enables the clinical assessment of lymphatics in lymphovenous malformations.

Targeting lymphatic function as a novel therapeutic intervention for rheumatoid arthritis

Although clinical outcomes for patients with rheumatoid arthritis (RA) have greatly improved with the use of biologic and conventional DMARDs, approximately 40% of patients do not achieve primary clinical outcomes in randomized trials, and only a small proportion achieve lasting remission. Over the past decade, studies in murine models point to the critical role of the lymphatic system in the pathogenesis and therapy of inflammatory-erosive arthritis, presumably by the removal of catabolic factors, cytokines and inflammatory cells from the inflamed synovium. Murine studies demonstrate that lymphatic drainage increases at the onset of inflammatory-erosive arthritis but, as inflammation progresses to a more chronic phase, lymphatic clearance declines and both structural and cellular changes are observed in the draining lymph node. Specifically, chronic damage to the lymphatic vessel from persistent inflammation results in loss of lymphatic vessel contraction followed by lymph node collapse, reduced lymphatic drainage, and ultimately severe synovitis and joint erosion. Notably, clinical pilot studies in patients with RA report lymph node changes following treatment, and thus draining lymphatic vessels and nodes could represent a potential biomarker of arthritis activity and response to therapy. Most importantly, targeting lymphatics represents an innovative strategy for therapeutic intervention for RA.

Lymphatic delivery of etanercept via nanotopography improves response to collagen-induced arthritis

Background

Evidence suggests lymphatic function mediates local rheumatoid arthritis (RA) flares. Yet biologics that target the immune system are dosed systemically via the subcutaneous (SC) administration route, thereby inefficiently reaching local lymphatic compartments. Nanotopography has previously been shown to disrupt tight cellular junctions, potentially enhancing local lymphatic delivery and potentially improving overall therapeutic efficacy.

Method

We first characterized nanotopography (SOFUSA™) delivery of an anti-TNF drug, etanercept, by comparing pharmacokinetic profiles to those obtained by conventional SC, intravenous (IV), and intradermal (ID) routes of administration, and assessed uptake of radiolabeled etanercept in draining lymph nodes (LNs) in single dosing studies. We then compared etanercept efficacy in a progressive rat model of collagen-induced arthritis (CIA), administered systemically via SC route of administration; via the regional lymphatics through ID delivery; or through a nanotopography (SOFUSA™) device at 10, 12, and 14 days post CIA induction. Measurements of hind limb swelling and near-infrared fluorescence (NIRF) imaging of afferent lymph pumping function and reflux were conducted on days 11, 13, and 18 post CIA induction and compared to untreated CIA animals. Univariate and multivariate analysis of variance were used to compare the group differences for percentage swelling and lymphatic contractile activity.

Results

Even though all three modes of administration delivered an equal amount of etanercept, SOFUSA™ delivery resulted in increased lymphatic pumping and significantly reduced swelling as compared to untreated, ID, and SC groups. Pharmacokinetic profiles in serum and LN uptake studies showed that using the nanotopography device resulted in the greatest uptake and retention in draining LNs.

Conclusions

Locoregional lymphatic delivery of biologics that target the immune system may have more favorable pharmacodynamics than SC or IV administration. Nanotopography may provide a more efficient method for delivery of anti-TNF drugs to reverse impairment of lymphatic function and reduce swelling associated with RA flares.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1323-z) contains supplementary material, which is available to authorized users.

Factors Associated with Lower Extremity Dysmorphia Caused by Lower Extremity Lymphoedema

OBJECTIVES

Indocyanine green (ICG) lymphography has been reported to be useful for the early diagnosis of lymphoedema. However, no study has reported the usefulness of ICG lymphography for evaluation of lymphoedema with lower extremity dysmorphia (LED). This study aimed to elucidate independent factors associated with LED in secondary lower extremity lymphoedema (LEL) patients.

METHODS

This was a retrospective observational study of 268 legs of 134 secondary LEL patients. The medical charts were reviewed to obtain data of clinical demographics and ICG lymphography based severity stage (leg dermal backflow [LDB] stage). LED was defined as a leg with a LEL index of 250 or higher. Logistic regression analysis was used to identify independent factors associated with LED.

RESULTS

LED was observed in 106 legs (39.6%). Multivariate analysis revealed that independent factors associated with LED were higher LDB stages compared with LDB stage 0 (LDB stage III; OR 17.586; 95% CI 2.055-150.482; p = .009) (LDB stage IV; OR 76.794; 95% CI 8.132-725.199; p < .001) (LDB stage V; OR 47.423; 95% CI 3.704-607.192; p = .003). On the other hand, inverse associations were observed in higher age (65 years or older; OR 0.409; 95% CI 0.190-0.881; p = .022) and higher body mass index (25 kg/m² or higher; OR 0.408; 95% CI 0.176-0.946; p = .037).

CONCLUSIONS

Independent factors associated with LED were elucidated. ICG lymphography based severity stage showed the strongest association with LED, and was useful for evaluation of progressed LEL with LED.

New diagnostic modalities in the evaluation of lymphedema

OBJECTIVE

Currently, lymphedema (LED) is typically diagnosed clinically on the basis of a patient's history and characteristic physical findings. Whereas the diagnosis of LED is sometimes confirmed by lymphoscintigraphy (LSG), the technique is limited in both its ability to identify disease and to guide therapy. Recent advancements provide opportunities for new imaging techniques not only to assist in the diagnosis of LED, based on anatomic changes, but also to assess contractile function and to guide therapeutic intervention. The purpose of this contribution was to review these imaging techniques.

METHODS

Literature for each technique is reviewed and discussed, and the evidence for each of these new diagnostic techniques was assessed on several criteria to determine if each could (1) establish whether disease is present, (2) determine the severity of the disease process, (3) define the pathophysiologic mechanism of the disease process, (4) demonstrate whether intervention is possible as well as what type, and (5) objectively grade the response to therapy.

RESULTS

LSG is currently the standard test to confirm LED. Duplex ultrasound (DUS) is a simple, readily available noninvasive test that can identify LED by specific tissue characteristics as well as the response to therapy. Magnetic resonance imaging and computed tomography scans similarly demonstrate the alterations in epidermal and subcutaneous tissue, but the latter can also detect obstructing neoplasms as a cause of secondary LED. Moreover, magnetic resonance lymphangiography details lymphatic vessels and nodes and their function. Newer fluorescence imaging techniques provide opportunities to image lymphatic anatomy and function. Visible microlymphangiography by fluorescein sodium is limited by tissue light absorption to imaging depths of 200 μm. Near-infrared fluorescence lymphatic imaging, a newer test using intradermal injection of indocyanine green, can penetrate several centimeters of tissue and can visualize the initial and conducting lymphatics, the lymph node basins, and the active function of lymphangions (the key module) in exquisite detail.

CONCLUSIONS

The availability and the noninvasive nature of DUS should make this modality the first choice for establishing the diagnosis of LED based on tissue changes. Further studies comparing DUS with LSG, however, are needed. The costs of magnetic resonance imaging and computed tomography limit their adoption as a means to regularly assess the lymphatics. Whereas lymphatic truncal anatomy and transit times can be delineated by the older technique of LSG, near-infrared fluorescence lymphatic imaging is rapid, highly sensitive, and repeatable and provides exquisite detail for lymphatic vessel anatomy and function of the lymphangions as well as the response to therapy.