Indocyanine green lymphography is superior to lymphoscintigraphy in imaging diagnosis of secondary lymphedema of the lower limbs

Progression of fluid infiltration on non-contrast magnetic resonance imaging in breast cancer-related lymphedema: A comparative analysis with indocyanine green lymphography

BACKGROUND

Non-contrast magnetic resonance imaging (NMRI) has been reported as valuable for the assessment of lymphedema. However, the correlation between NMRI findings and indocyanine green lymphography (ICG-L) findings remains elusive.

METHODS

This single-center retrospective study included 26 patients diagnosed with breast cancer-related lymphedema. We examined the prevalence of fluid infiltration in eight regions of the upper extremity, the type of fluid distribution, and the dominant segment of edema on NMRI in comparison to the ICG-L stage. Statistical analysis was performed using the Cochran-Armitage trend test, Spearman's rank correlation test, and Fisher's exact test.

RESULTS

The regional fluid infiltration significantly increased with the progression of the ICG-L stage (hand, forearm, elbow, and upper arm: p = 0.003, <0.001, <0.001, and <0.001, respectively). The fluid distribution significantly advanced with the progression of the ICG-L stage as follows (rs = 0.80; p < 0.001): no edema in ICG-L stage 0, edema in either the hand or elbow in ICG-L stage I, edemas in both the elbow and hand in ICG-L stage II, three segmental edemas centered on the forearm or elbow in ICG-L stage III, and edema encompassing the entire upper limb in ICG-L stage IV-V. Additionally, the dominant segment of edema tended to shift from the hand to the elbow and further to the forearm as the ICG-L stage progressed (p < 0.001).

CONCLUSIONS

Fluid infiltration observed on NMRI exhibited distinct patterns with the progression of the ICG-L stage. We believe that anatomical information regarding fluid distribution would potentially contribute to optimizing surgical efficacy.

Three-dimensional non-contrast magnetic resonance lymphography severity stage for upper extremity lymphedema

PURPOSES

Non-contrast magnetic resonance lymphography (NMRL) has recently shown the capability of evaluating anatomical fluid distribution in upper extremity lymphedema (UEL). However, there is still a lack of knowledge about the correlation between the characteristic three-dimensional (3D) NMRL findings and the indocyanine green lymphography (ICG-L) findings. Our goal was to clarify the relationship between the 3D NMRL findings and the ICG-L findings.

METHODS

Medical charts of patients with secondary UEL who underwent NMRL and ICG-L between January 2018 to October 2021 were reviewed. The upper extremities were divided into 6 regions; the hand, elbow, and the radial and ulnar aspects of the forearm and the upper arm. We investigated the prevalence of characteristic 3D NMRL patterns (Mist/Spray/Inky) in each region based on the ICG-L stage. We also examined the association between the 3D NMRL stage which we proposed and the ICG-L stage, and other clinical factors.

RESULTS

A total of 150 regions of 25 patients with upper extremities lymphedema were enrolled in the study. All of the characteristic patterns increased significantly as the ICG-L stage advanced (p < 0.001, < 0.001, and < 0.001, respectively). The predominant NMRL patterns changed significantly from the Early pattern (Mist pattern) to the Advanced pattern (Inky/Spray pattern) as the ICG-L stage progressed (p < 0.001). The higher Stage of 3D NMRL was significantly associated with the progression of the ICG-L stage (rs = 0.80, p < 0.001).

CONCLUSIONS

Characteristic 3D NMRL patterns and the 3D NMRL Stage had a significant relationship with the ICG-L stage and other clinical parameters. This information may be an efficient tool for a more precise and objective evaluation of various treatments for UEL patients.

Advances in lymphedema: An under-recognized disease with a hopeful future for patients

Lymphedema has traditionally been underappreciated by the healthcare community. Understanding of the underlying pathophysiology and treatments beyond compression have been limited until recently. Increased investigation has demonstrated the key role of inflammation and resultant fibrosis and adipose deposition leading to the clinical sequelae and associated reduction in quality of life with lymphedema. New imaging techniques including magnetic resonance imaging (MRI), indocyanine green lymphography, and high-frequency ultrasound offer improved resolution and understanding of lymphatic anatomy and flow. Nonsurgical therapy with compression, exercise, and weight loss remains the mainstay of therapy, but growing surgical options show promise. Physiologic procedures (lymphovenous anastomosis and vascularized lymph node transfers) improve lymphatic flow in the diseased limb and may reduce edema and the burden of compression. Debulking, primarily with liposuction to remove the adipose deposition that has accumulated, results in a dramatic decrease in limb girth in appropriately selected patients. Though early, there are also exciting developments of potential therapeutic targets tackling the underlying drivers of the disease. Multidisciplinary teams have developed to offer the full breadth of evaluation and current management, but the development of a greater understanding and availability of therapies is needed to ensure patients with lymphedema have greater opportunity for optimal care.

Optimizing Outcomes in Lymphedema Reconstruction

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Describe current surgical techniques for treating primary and secondary lymphedema. 2. Optimize the surgical care of patients with lymphedema.

SUMMARY

Over the past decade, significant advances have been made in the surgical treatment of lymphedema. The most notable changes have been the reintroduction and evolution of physiologic techniques, including lymphovenous bypass-sometimes referred to as lymphovenous anastomosis in the literature-and vascularized lymph node transplant. These surgical modalities are now often used as first-line surgical options or may be combined with nonphysiologic approaches, including direct excision and suction-assisted lipectomy. Surgeons continue to debate the most appropriate sequence and combination of surgical treatment, particularly for patients at both extremes of the severity spectrum. Furthermore, debate remains around the need to apply different treatment approaches for patients with upper versus lower extremity involvement and primary versus secondary cause. In this article, we provide a summary of the surgical techniques currently used for both primary and secondary lymphedema and provide our recommendations for optimizing the surgical care of patients with lymphedema.

In Vivo Dynamic and Static Analysis of Lymphatic Dysfunction in Lymphedema Using Near-Infrared Fluorescence Indocyanine Green Lymphangiography

BACKGROUND

Near-infrared fluorescence indocyanine green lymphangiography, a primary modality for detecting lymphedema, which is a disease due to lymphatic obstruction, enables real-time observations of lymphatics and reveals not only the spatial distribution of drainage (static analysis) but also information on the lymphatic contraction (dynamic analysis).

METHODS

We have produced total lymphatic obstruction in the upper limbs of 18 Sprague-Dawley rats through the dissection of proximal (brachial and axillary) lymph nodes and 20-Gy radiation (dissection limbs). After the model formation for 1 week, 9 animal models were observed for 6 weeks using near-infrared fluorescence indocyanine green lymphangiography by injecting 6-μL ICG-BSA (indocyanine green-bovine serum albumin) solution of 20-μg/mL concentration. The drainage pattern and leakage of lymph fluid were evaluated and time-domain signals of lymphatic contraction were observed in the distal lymphatic vessels. The obtained signals were converted to frequency-domain spectrums using signal processing.

RESULTS

The results of both static and dynamic analyses proved to be effective in accurately identifying the extent of lymphatic disruption in the dissection limbs. The static analysis showed abnormal drainage patterns and increased leakage of lymph fluid to the periphery of the vessels compared with the control (normal) limbs. Meanwhile, the waveforms were changed and the contractile signal frequency increased by 58% in the dynamic analysis. Specifically, our findings revealed that regular lymphatic contractions, observed at a frequency range of 0.08 to 0.13 Hz in the control limbs, were absent in the dissection limbs. The contractile regularity was not fully restored for the follow-up period, indicating a persistent lymphatic obstruction.

CONCLUSIONS

The dynamic analysis could detect the abnormalities of lymphatic circulation by observing the characteristics of signals, and it provided additional evaluation indicators that cannot be provided by the static analysis. Our findings may be useful for the early detection of the circulation problem as a functional evaluation indicator of the lymphatic system.

Investigation of optimizing indocyanine green solution for in vivo lymphatic research using near-infrared fluorescence indocyanine green lymphangiography

Despite the tireless efforts of many researchers in lymphatic research, indocyanine green (ICG) solution conditions suitable for lymphatic circulation tests have not been perfectly established yet. We aimed to investigate the optimal in vivo conditions of ICG solution to avoid photobleaching and quenching effects, which may affect the accuracy of lymphatic circulation evaluation. After ICG fluorescence intensity (or ICG intensity) was assessed under different in vitro conditions, the image quality of brachial lymph nodes (LNs) and collecting lymphatic vessels (LVs) in eight rats was investigated. The in vitro results showed that ICG intensity depends on concentration and time in various solvents; however, the brightest intensity was observed at a concentration of 8-30 μg/mL in all solvents. ICG concentration in the albumin (bovine serum albumin; BSA) solution and rat's plasma showed more than two times higher fluorescence intensity than in distilled water (DW) in the same range. However, saline reduced the intensity by almost half compared to DW. In the in vivo experiment, we obtained relatively high-quality images of the LNs and LVs using ICG in the BSA solution. Even at low concentrations, the result in the BSA solution was comparable to those obtained from high-concentration solutions commonly used in conventional circulation tests. This study provides valuable information about the conditions for optimal ICG intensity in near infrared fluorescence indocyanine green (NIRF-ICG) lymphangiography, which may be useful not only for the diagnosis of lymphatic circulation diseases such as lymphedema but also for preclinical research for the lymphatic system.

The relationship between the degree of subcutaneous fluid accumulation and the lymphatic diameter

BACKGROUND

The relationship between the fluid accumulation in the subcutaneous tissue and the lymphatic degeneration in the lymphedematous limbs has not been elucidated, and we have evaluated it in the current study.

METHODS

Twenty-five patients (50 limbs) were included in this retrospective study. We performed lymphatic ultrasound by separating the limbs into four lymphosomes: the saphenous (medial) thigh, saphenous (medial) calf, lateral thigh, and lateral calf. In each lymphosome, the lymphatic diameter, the degree of lymphatic degeneration, and the fluid accumulation in the subcutaneous tissue were evaluated. The lymphatic vessels were detected based on the index of D-CUPS (Doppler, Crossing, Uncollapsibe, Parallel, and Superficial fascia). Lymphatic degeneration was diagnosed based on the NECST (Normal, Ectasis, Contraction, and Sclerosis Type) classification.

RESULTS

All patients were women with a mean age of 62.7 years. Lymphatic vessels were detected using lymphatic ultrasonography in 50 saphenous (medial) thigh lymphosomes, 43 saphenous (medial) calf lymphosomes, 34 lateral thigh lymphosomes, and 22 lateral calf lymphosomes. The fluid accumulation tended to be more acute in the more severe stages of lymphedema. As for the NECST classification, the normal type was observed only in the areas without fluid accumulation. Among the other areas, the percentage of contraction type was the largest in the area with slight edema and decreased in the areas with severe edema.

CONCLUSION

The lymphatic vessels were dilated to a greater extent in legs with more severe fluid accumulation. Therefore, there is no hesitation needed to perform lymphaticovenous anastomosis because of severe lymphedema.

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.

Gluteal lymphoedema associated with lower extremity lymphoedema: A preliminary study with indocyanine green lymphography and magnetic resonance imaging

INTRODUCTION

Indocyanine green (ICG) lymphography studies have identified that one in three to five patients with cancer-related lower extremity lymphoedema (LEL) demonstrated dermal backflow extending to the gluteal region. This study aimed to further characterize gluteal lymphoedema using contemporaneous magnetic resonance imaging (MRI).

PATIENTS AND METHODS

Twenty-eight patients with unilateral advanced LEL who underwent both ICG lymphography and MRI prior to any surgical procedure were included in this study. The patients were divided into two groups with/without gluteal lymphoedema by the presence of dermal backflow on ICG lymphography. MRI was used to evaluate tissue changes.

RESULTS

Ten patients demonstrated gluteal lymphoedema on ICG lymphography and had a higher incidence of skin hypertrophy in the gluteal region. However, no difference in excess leg volume was found between the two groups. A trend of increasing gluteal subcutaneous tissue in the affected side was identified in patients with gluteal lymphoedema with a median increase of 20% compared with an 11% increase in the non-gluteal lymphoedema group. The excess gluteal subcutaneous tissue was positively correlated to ipsilateral excess leg volume.

CONCLUSION

The gluteal lymphoedema group on ICG lymphography had skin thickening in the gluteal region and was likely identified in the secondary cancer-related group. Surgical and conservative management options for gluteal lymphoedema need to be considered in advanced LEL.

Imaging of the Lymphatic Vessels for Surgical Planning: A Systematic Review

BACKGROUND

Secondary lymphedema is a common complication after surgical or radiotherapeutic cancer treatment. (Micro) surgical intervention such as lymphovenous bypass and vascularized lymph node transfer is a possible solution in patients who are refractory to conventional treatment. Adequate imaging is needed to identify functional lymphatic vessels and nearby veins for surgical planning.

METHODS

A systematic literature search of the Embase, MEDLINE ALL via Ovid, Web of Science Core Collection and Cochrane CENTRAL Register of Trials databases was conducted in February 2022. Studies reporting on lymphatic vessel detection in healthy subjects or secondary lymphedema of the limbs or head and neck were analyzed.

RESULTS

Overall, 129 lymphatic vessel imaging studies were included, and six imaging modalities were identified. The aim of the studies was diagnosis, severity staging, and/or surgical planning.

CONCLUSION

Due to its utility in surgical planning, near-infrared fluorescence lymphangiography (NIRF-L) has gained prominence in recent years relative to lymphoscintigraphy, the current gold standard for diagnosis and severity staging. Magnetic resonance lymphography (MRL) gives three-dimensional detailed information on the location of both lymphatic vessels and veins and the extent of fat hypertrophy; however, MRL is less practical for routine presurgical implementation due to its limited availability and high cost. High frequency ultrasound imaging can provide high resolution imaging of lymphatic vessels but is highly operator-dependent and accurate identification of lymphatic vessels is difficult. Finally, photoacoustic imaging (PAI) is a novel technique for visualization of functional lymphatic vessels and veins. More evidence is needed to evaluate the utility of PAI in surgical planning.

Real-time image-sharing to educate a patient with lymphoedema on self-care: a case study

INTRODUCTION

Compression therapy is important in oedema control in lymphoedema. However, some patients have difficulties starting compression therapy because standard self-care education does not enable them to fully understand lymphoedema and recognise it as their problem. To overcome this, real-time image-sharing education, using a combination of indocyanine green lymphography (ICG) and ultrasonography, may be used to educate patients. In this case study, real-time image-sharing education promoted decision-making and behaviour change in a patient with lower extremity lymphoedema so she would wear elastic stockings.

CASE

A 51-year-old woman with a BMI of 31.7 kg/m² and secondary lower extremity lymphoedema following cervical cancer surgery did not adhere to self-care instructions regarding wearing elastic stockings for 5 years. The oedema worsened, her limb circumference increased and she had two episodes of cellulitis within a year. Because the patient had a negative attitude towards elastic stockings, real-time image-sharing education was used to promote recognition of illness using ICG and an understanding of the condition of lymphoedema using ultrasonography. After the images were shared and explained, the patient discussed her recognition and understanding of lymphoedema, then decided to use compression stockings. She continued to wear them for 4 months, and her limb circumference decreased.

CONCLUSION

Real-time image-sharing education using ICG and ultrasonography as self-care support for a lymphoedema patient who would not start compression therapy could result in behavioural changes and the patient starting and continuing to wear elastic stockings.

Indocyanine green lymphography as novel tool to assess lymphatics in patients with lipedema

OBJECTIVE

Lipedema is a chronic and progressive disease associated with lymphatic impairment at later stages. The aim of our study was to describe the functional status and anatomy of lower limb superficial lymphatic system using indocyanine green (ICG) lymphography in patients with lipedema.

METHODS

Following ICG injection at the dorsum of the foot, distance (cm) covered by the dye at 10 (T10') and 25 min (T25') was measured and normalized for limb length. If the dye did not reach the groin within 25 min, patients were classified as "drainage-needing" group (DNG). Values of fat and lean distribution assessed by dual-energy X-ray absorptiometry were extracted, and correlation analysis was performed. Furthermore, anatomical patterns of superficial lymphatics were assessed.

RESULTS

Overall, 45 women were included, 25 (56%) of whom were classified as DNG. Symptoms duration was significantly associated with DNG status at multivariate analysis (odds ratio 1.07; 95% CI 1.01-1.14; p = 0.047). Moreover, Spearman's analysis showed a negative correlation between symptoms duration and T25' dye migration (r = -0.469; p = 0.037). Overall, no major anatomical lymphatic changes were found.

CONCLUSIONS

Present study suggests that lymphatic functioning in patients with lipedema correlates with symptoms duration. Further research on larger cohorts should verify our findings and clarify their potential therapeutic implications. Overall, ICG lymphography may be promising technique to assess both lymphatic anatomy and functioning in patients with lipedema.

Photoacoustic lymphangiography exhibits advantages over near-infrared fluorescence lymphangiography as a diagnostic tool in patients with lymphedema

OBJECTIVE

Photoacoustic imaging (PAI) is a new technique that can evaluate the vascular system using photoacoustic effects. The present study compared the ability of the new photoacoustic lymphangiography (PAL) method and more standard near-infrared fluorescence (NIRF) to image the lymphatic system in patients with secondary lymphedema following gynecological cancer surgery.

METHODS

Patients with secondary lymphedema in the lower extremities following gynecologic cancer surgery, who were assessed using PAL between May 2018 and January 2019 were recruited. NIRF was performed first using 5.0 mg/mL of indocyanine green injected using a 0.2-cc 30-gauge needle. Correlations between NIRF and PAL findings on patient images were subsequently examined.

RESULTS

Seventeen patients with secondary lymphedema were enrolled. The mean age of the patients was 61 ± 11 years. The imaging sites were the medial lower leg in 15 patients, the posterior lower leg in nine patients, the lateral lower leg in seven patients, the medial knee in four patients, and other areas in three patients. A total of 38 pictures were obtained. Five distinct lymphatic patterns were observed over the entire sample using PAL: straight, winding, spiderweb, nebulous, and black-out pattern Eighteen of the 24 limbs (75%) that exhibited a linear pattern in NIRF exhibited a straight pattern in PAL, and 19 of the 20 limbs (95%) that exhibited a splash pattern in NIRF exhibited a winding or spider web pattern in PAL. Eight limbs exhibiting diffuse patterns without linear or splash patterns with NIRF were all nebulous or black-out patterns in PAL. This suggests that more severe lymphatic degeneration was associated with poorer visualization in PAL.

CONCLUSIONS

NIRF plays an important role in lymphedema treatment. In the present study, various PAL patterns were compared with those observed using NIRF. PAL provided clearer images including transectional views, which were not available using NIRF, and may promote further understanding of the changes in the lymphatic structure and function in patients with secondary lymphedema.

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.

Prospective Validation of Indocyanine Green Lymphangiography Staging of Breast Cancer-Related Lymphedema

Simple Summary

Indocyanine green lymphangiography (ICG-L) allows real-time investigation of lymphatics; however, the applicability in evaluating breast cancer-related lymphedema (BCRL) is sparse and not well established. In this prospective study, we aimed to validate ICG-L assessment of BCRL in a large patient group. We found that evaluation of BCRL with ICG-L was easy and safe to perform in the outpatient clinic and provided unique disease information unobtainable by clinical assessment alone. Future studies that evaluate the efficacy of therapeutic treatments on lymphatic function morphology should incorporate lymphatic imaging as an outcome.

Abstract

Indocyanine green lymphangiography (ICG-L) allows real-time investigation of lymphatics. Plastic surgeons performing lymphatic reconstruction use the ICG-L for patient selection and stratification using the MD Anderson (MDA) and the Arm Dermal Backflow (ADB) grading systems. However, the applicability of ICG-L in evaluating breast cancer-related lymphedema (BCRL) is sparse and not well established. This study comprehensively examines the usability of ICG-L in the assessment of BCRL. We prospectively performed ICG-L in 237 BCRL patients between January 2019 and February 2020. The aim of this study was to assess the interrater and intrarater agreement and interscale consensus of ratings made using the MDA and ADB scales. Three independent raters performed a total of 2607 ICG-L assessments. The ICG-L stage for each grading system was correlated to the lymphedema volume to assess the agreement between the ICG-L stage and clinical severity. The interrater agreement was near perfect for the MDA scale (kappa 0.82–0.90) and the ADB scale (kappa 0.80–0.91). Similarly, we found a near-perfect intrarater agreement for the MDA scale (kappa 0.84–0.94) and the ADB scale (kappa 0.88–0.89). The agreement between the MDA and the ADB scales was substantial (kappa 0.65–0.68); however, the ADB scale systematically overestimated lower ICG-L stages compared to the MDA scale. The volume of lymphedema correlated slightly with MDA stage (Spearmans rho = 0.44, p < 0.001) and ADB stage (r_s = 0.35, p < 0.001). No serious adverse events occurred. The staging of BCRL with ICG-L is reliable, safe, and provides unique disease information unobtainable with clinical measurements alone. The MDA scale seems to provide better disease stratification compared to the ADB scale.

Diagnosis of Lymphatic Dysfunction by Evaluation of Lymphatic Degeneration with Lymphatic Ultrasound

Background: The standard examination for diagnosing lymphedema is lymphoscintigraphy, which has a disadvantage in versatility and radiation exposure. We have reported the usefulness of echography in observing the lymphatic degeneration. The purpose of this study was to investigate the usefulness of lymphatic ultrasound in diagnosing lymphedema. Methods and Results: The study included 14 patients (28 lower limbs) who underwent lymphaticovenous anastomosis for lower limb lymphedema. Preoperative echography with a common 18-MHz linear probe was used to detect lymphatic vessels. We evaluated abnormal expansion or sclerosis of lymphatic vessels in the medial legs, which indicated the presence of lymphedema. We proposed the method "D-CUPS" on how to detect and observe the lymphatic vessels. We then performed indocyanine green (ICG) lymphography to diagnose lymphedema. The results of examination were compared. Stage 1 lymphedema was diagnosed in 9 limbs, Stage 2a in 7, Stage 2b in 8, and Stage 3 in 4. Lymphatic vessel detection was possible in all 28 medial thighs and in 27 medial lower legs. The sensitivity and specificity for diagnosis of lymphedema based on echography of the medial leg were 95.0% and 100.0%, respectively. The accuracy rate was 94.6%. We could detect lymphatic vessels with echography in 39 of 54 areas that failed detection using lymphoscintigraphy or ICG lymphography (72.2%). Conclusion: The location and degeneration of lymphatic vessels in lymphedematous limbs can be evaluated with a commonly used ultrasound device. Although exclusion of comorbidities is still necessary, lymphatic ultrasound has potential for use in diagnosis of lymphedema or lymphatic dysfunction.

Lymphaticovenous anastomosis for advanced-stage lower limb lymphedema

BACKGROUND

Early-stage lymphedema patients are said to be candidates for lymphaticovenous anastomosis (LVA). The progressions in the preoperative examinations have made it possible to find the suitable lymphatic vessels even in advanced-stage lymphedema. The aim of this study was to elucidate the surgical effect of LVA in cases of advanced-stage lymphedema.

METHODS

We evaluated 42 limbs of 34 patients with lymphoscintigraphic type 4 or 5. A mean disease duration was 7.5 ± 6.5 years. We performed multi-lymphosome indocyanine green (ICG) lymphography preoperatively to detect the saphenous lymphatics, the lateral calf lymphatics, and the lateral thigh lymphatics. We also performed ultrasound to detect the subcutaneous veins and the dilated lymphatic vessels. The pre- and postoperative evaluation was made by the sum of circumference measurements at 6 points per limb.

RESULTS

The mean number of anastomosis per limb was 2.8 (range, 1-5). Of the 41 limbs for which we performed ICG lymphography, we found the saphenous lymphatics in 29 limbs (70.7%), lateral calf lymphatics in 28 limbs (68.3%), and lateral thigh lymphatics in 21 limbs (51.2%). We found at least 1 linear pattern in ICG lymphography for 39 limbs (95.1%). The mean pre- and postoperative circumference (sum of 6 points) were 221.7 ± 4.9 cm and 215.9 ± 4.9 cm, which was significantly reduced (p < .01).

CONCLUSIONS

LVA was effective for advanced-stage lymphedema patients. An adequate preoperative examination with plural imaging methods seems helpful for achieving a successful surgical result.

Compression Pressure Variability in Upper Limb Multilayer Bandaging Applied by Lymphedema Therapists

Background: Multilayer bandaging (MLB) is often used for lymphedema treatment. Even experienced lymphedema therapists have difficulty applying bandages correctly. The aim of this study was to demonstrate upper limb MLB pressure variability applied by lymphedema therapists. Methods and Results: Twenty-four lymphedema therapists were asked to apply MLB to the healthy volunteer's upper limb. The participants consisted of 20 females and 4 males with a mean age of 43.4 (range: 24-62) years. They included licensed massage therapists, nurses, a judo therapist, an occupational therapist, and a medical doctor. Twenty therapists (83.3%) had clinical experience applying MLB. Compression pressure was measured with PicoPress at 5 cm proximal to the wrist, immediately after the application (phase 1) and after exercise (phase 2). The mean MLB pressure was 67.7 ± 5.0 mmHg in phase 1 and 55.3 ± 4.1 mmHg in phase 2, which were significantly different (p = 1.2 × 10^-10). There was a weak negative correlation between how long the therapist had been practicing MLB and MLB pressure (R = 0.29). Seventeen participants (70.8%) expressed that they had a target pressure in mind when performing MLB. Among the 17 participants, there was no correlation between the target and actual pressures (R = -0.055). Only three participants (17.6%) had an actual MLB pressure within 5 mmHg of their target. Conclusions: The mean MLB pressure was 55.3 ± 4.1 mmHg, which was thought to be too high for the upper limb. Education about applying appropriate MLB pressures to the limbs is necessary.

Major Changes in Lymphatic Microsurgery and Microvascular Surgery in Past 20 Years

This article summarizes the major changes seen in lymphatic microsurgery and microvascular surgery in first 20 years of the 21st century. Lymphatic microsurgery is discussed first, as more advances have been seen in imaging of the lymphatic system, lymphatico-venous anastomosis, and vascularized lymph node transfers. During the past 2 decades, there have been more patient population changes than major technical evolutions in microvascular surgery, although new techniques and modifications emerged and became clinical routines, with the landscape of microvascular surgery evolving in this time period.

Relationship between perimetric increase and fluoroscopic pattern type in secondary upper limb lymphedema observed by Indocyanine green lymphography

To ascertain the relationship between the perimetric differences obtained between the limbs and the type of fluoroscopic pattern observed by Indocyanine green (ICG) lymphography in patients with upper limb lymphedema.A correlational descriptive study was carried out in 19 patients with upper limb lymphedema secondary to breast cancer. The perimetric increase was recorded in 11 anatomical regions after ICG injection, fluoroscopic patterns were identified using an infrared camera. The ICG patterns were categorized into worse (stardust, diffuse) or better (linear, splash) patterns.The pattern coincidence between the anterior and posterior regions of the edematous extremities was 45%. At the wrist level, a difference of 2 cm was associated with the presence of a worse fluoroscopic pattern, whereas perimeter differences of 4.25 cm in the elbow and 2.25 cm in the arm (12 cm from the epicondyle) were associated with the presence of a better fluoroscopic pattern.The perimetric differences observed between the healthy and affected upper limbs in 4 specific anatomical areas allowed us to predict the type of fluoroscopic pattern. ICG lymphography has facilitated the study of the posterior regions of edema, which are difficult to visualize using other imaging techniques.

Changes in Indocyanine Green Lymphography Patterns after Physical Treatment in Secondary Upper Limb Lymphedema

Indocyanine green (ICG) lymphography is used to evaluate the lymphatic function before and after pneumatic compression or post-manual lymphatic drainage. The aim of this study was to ascertain the changes in the fluoroscopic pattern produced by the provision of complex physical therapy. This prospective analytic (pretest-posttest) study was conducted in 19 patients with upper lymphedema secondary to breast cancer. Nine patients were excluded due to ICG found after 3 weeks. The ICG patterns were analyzed under basal conditions and after three weeks of treatment. After the treatment, 45% of the patients presented tracer remains in the affected limb, and this finding was significantly related to time of the lymphedema development. In one subject, the patterns remain unchanged or cannot be defined. Three of the ten patients observed present the worsening of at least 1 of the patterns and in the rest of the subjects, six cases, the improvement of the patterns is observed. In 60% of the cases, the most severe pattern reversed towards slight (splash) cases, and moderate cases reversed towards a slight case in 70% of cases. Therefore, after treatment with complex physical therapy, the pathological patterns observed in the pretest, which evolved positively, reverted their severity toward milder disease patterns or towards normality.

Multilymphosome injection indocyanine green lymphography can detect more lymphatic vessels than lymphoscintigraphy in lymphedematous limbs

BACKGROUND

Sometimes, injecting indocyanine green (ICG) or isotope at distal limbs is insufficient especially in cases with low lymphatic function. The purpose of this study was to elucidate the usefulness of multi-lymphosome injection ICG lymphography.

METHODS

Two hundred and six lower limbs of 103 patients were included. ICG lymphography was performed by injecting ICG in three lymphosomes per limb: dorsum of foot (saphenous lymphatics), the proximal side of the lateral condyle (lateral calf lymphatics), and the lateral side of the superior edge of the knee (lateral thigh lymphatics). We observed the presence or absence of a linear pattern at each injection site with a near-infrared camera. Lymphoscintigraphy was performed by injecting an isotope in the first web space, conventionally. Whole body scintigrams were taken 60 min after injection.

RESULTS

In multi-lymphosome ICG lymphography, the lateral thigh lymphatics were observed as a linear pattern in 75.2% of patients, the lateral calf lymphatics in 72.8%, and the saphenous lymphatics in 84.5% of patients. There was not a significant difference between secondary and primary lymphedema (p = 0.57, 0.77, and 0.56 in the lateral thigh, the lateral calf, and the saphenous lymphatics, respectively). Among the 12 limbs classified as Type 5, at least one linear pattern was found in 10 limbs (83.3%).

CONCLUSIONS

We observed a linear pattern in 83.3% of the limbs that were lymphoscintigraphic Type 5 by using multi-lymphosome ICG lymphography. There is a possibility that the results of this study can increase the number of patients eligible for lymphatico-venous anastomosis (LVA) and increase the success rate of LVA.

Lymphedema Liposuction with Immediate Limb Contouring

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Liposuction is the treatment of choice for solid predominant extremity lymphedema. The classic lymphedema liposuction technique does not remove skin excess created following bulk removal. The skin excess is presumed to resolve with spontaneous skin contracture. We investigated the technique of simultaneously performing liposuction with immediate skin excision in patients with solid predominant lymphedema and compared the outcome with that from the classic technique.

Visualization of Accessory Lymphatic Pathways, before and after Manual Drainage, in Secondary Upper Limb Lymphedema Using Indocyanine Green Lymphography

Manual Lymphatic Drainage (MLD) appears to stimulate lymphatic contraction, aid in the development of secondary derivation pathways, and stimulate the appearance of collateral pathways that could function as the main drainage routes of the limb in case of lymphedema. Through stretching, call up maneuvers are used to stimulate lymphangion reflex contraction and, therefore, lymphatic function. The aim was to describe the presence of areas and pathways of collateral lymphatic drainage under basal conditions and to determine, using Indocyanine Green (ICG) lymphography, whether an increase in these pathways occurs after 30 min of manual lymphatic stimulation with only call up maneuvers according to the Leduc Method^®®. In this prospective analytical study (pretest–posttest), the frequency of presentation of areas and collateral lymphatic pathways was analyzed in 19 patients with secondary lymphedema of the upper limb after breast cancer using an infrared camera. Analyses were completed at three time points: after ICG injection, at baseline (pretest), and after the application of MLD (post-test). The Leduc Method maneuvers were applied to the supraclavicular and axillary nodes, chest, back, Mascagni, and Caplan pathways. The areas visualized in the pretest continued to be visible in the posttest. Additional pathways and fluorescent areas were observed after the maneuvers. The McNemar test showed statistical significance (p = 0.008), the odds ratio was infinite, and the Cohen’s g value was equal to 0.5. Manual stimulation by call up maneuvers increased the observation frequency of areas and collateral lymphatic pathways. Therefore, ICG lymphography appears to be a useful tool for bringing out the routes of collateral bypass in secondary lymphoedema after cancer treatment.

Supermicrosurgical Lymphaticovenous Anastomosis as Alternative Treatment Option for Moderate-to-Severe Lower Limb Lymphedema

BACKGROUND

Supermicrosurgical lymphaticovenous anastomosis (LVA) alleviates lymphedema by draining stagnant lymph from the lymphatic vessels into the venous system. Nevertheless, LVA is believed to be unsuitable for treating moderate-to-severe lymphedema presenting diffuse-pattern dermal backflow (DB). Dermal backflow is considered to be the sign of superficial lymphatic functional failure that renders LVA ineffective. Based on a current algorithm, a more invasive vascularized lymph node flap transfer is recommended instead of LVA. This retrospective study aimed to further investigate and possibly challenge this concept.

STUDY DESIGN

One-hundred patients with unilateral lymphedematous lower limbs who underwent LVA were included. Patients were divided into Group I (10 patients with mild lymphedema) and Group II (90 patients with moderate-to-severe lymphedema). Demographic data and intraoperative findings were recorded. The post-LVA volume reductions by magnetic resonance volumetry were recorded and analyzed.

RESULTS

Preoperatively, significant differences were found in BMI (20.6 vs 26.0 kg/m², p = 0.004) and the volume gained in the lymphedematous limb (396.8 mL vs 1,056.8 mL, p = 0.005) between Groups I and II. Postoperatively, a significant median post-LVA volume reduction (-282.0 mL vs -763.5 mL, p = 0.022) was found in Group II. However, there were no differences in the percentages of post-LVA volume reduction (-43.8% vs -36.4%, p = 0.793) in Groups I and II.

CONCLUSIONS

The use of supermicrosurgical LVA is as effective at treating moderate-to-severe lymphedema as milder lymphedema. The indication for LVA should be broadened to include such cases.

Baseline Lymphatic Dysfunction Amplifies the Negative Effects of Lymphatic Injury

BACKGROUND

Genetic mutations and obesity increase the risk of secondary lymphedema, suggesting that impaired lymphatic function before surgical injury may contribute to disease pathophysiology. Previous studies show that obesity not only decreases lymphatic function, but also markedly increases pathologic changes, such as swelling, fibroadipose deposition, and inflammation. However, although these reports provide circumstantial evidence supporting the hypothesis that baseline lymphatic defects amplify the effect of lymphatic injury, the mechanisms regulating this association remain unknown.

METHODS

Baseline lymphatic morphology, leakiness, pumping, immune cell trafficking, and local inflammation and fibroadipose deposition were assessed in wild-type and Prox1-haploinsufficient (Prox1) mice, which have previously been shown to have abnormal vasculature without overt evidence of lymphedema. In subsequent experiments, wild-type and Prox1 mice underwent popliteal lymph node dissection to evaluate the effect of lymphatic injury. Repeated testing of all variables was conducted 4 weeks postoperatively.

RESULTS

At baseline, Prox1 mice had dilated, leaky lymphatic vessels corresponding to low-grade inflammation and decreased pumping and transport function, compared with wild-type mice. Popliteal lymph node dissection resulted in evidence of lymphedema in both Prox1 and wild-type mice, but popliteal lymph node dissection-treated Prox1 mice had increased inflammation and decreased lymphatic pumping.

CONCLUSIONS

Subclinical lymphatic dysfunction exacerbates the pathologic changes of lymphatic injury, an effect that is multifactorial and related to increased lymphatic leakiness, perilymphatic accumulation of inflammatory cells, and impaired pumping and transport capacity. These findings suggest that preoperative testing of lymphatic function may enable clinicians to more accurately risk-stratify patients and design targeted preventative strategies.

Usefulness of preoperative echography for detection of lymphatic vessels for lymphaticovenous anastomosis

Case 1: A 63-year-old woman with secondary lower limb lymphedema. As it was difficult to detect the lymphatic vessels in the right thigh in indocyanine green lymphography because of thick fat, we tried echography and observed circular structures beneath the superficial fascia. Intraoperatively, we found a dilated lymphatic vessel just as observed on echography. Case 2: A 45-year-old woman with primary lower limb lymphedema. As she was allergic to iodinated contrast medium, we could not use indocyanine green lymphography preoperatively. In echography, we found vascular architectures and found the dilated lymphatic vessels intraoperatively just as observed on echography. In conclusion, application of echography in detecting the lymphatic vessels was useful as a preoperative examination of lymphaticovenous anastomosis.

A vicious circle in chronic lymphoedema pathophysiology? An adipocentric view

Chronic lymphoedema is a disease caused by a congenital or acquired damage to the lymphatic system and characterized by complex chains of pathophysiologic events such as lymphatic fluid stasis, chronic inflammation, lymphatic vessels impairment, adipose tissue deposition and fibrosis. These events seem to maintain and reinforce themselves through a positive feedback loop: regardless of the initial cause of lymphatic stasis, the dysfunctional adipose tissue and its secretion products can worsen lymphatic vessels' function, aggravating lymph leakage and stagnation, which can promote further adipose tissue deposition and fibrosis, similar to what may happen in obesity. In addition to the current knowledge about the tight and ancestral interrelation between immunity system and metabolism, there is evidence for similarities between obesity-related and lymphatic damage-induced lymphoedema. Together, these observations indicate strong reciprocal relationship between lymphatics and adipose tissue and suggest a possible key role of the adipocyte in the pathophysiology of chronic lymphoedema's vicious circle.

Advances in fluorescent-image guided surgery

Fluorescence imaging is increasingly gaining intraoperative applications. Here, we highlight a few recent advances in the surgical use of fluorescent probes.

Current status of optical imaging for evaluating lymph nodes and lymphatic system

Optical imaging techniques use visual and near infrared rays. Despite their considerably poor penetration depth, they are widely used due to their safe and intuitive properties and potential for intraoperative usage. Optical imaging techniques have been actively investigated for clinical imaging of lymph nodes and lymphatic system. This article summarizes a variety of optical tracers and techniques used for lymph node and lymphatic imaging, and reviews their clinical applications. Emerging new optical imaging techniques and their potential are also described.