Indocyanine Green Lymphography Findings in Primary Leg Lymphedema

Concordance between preoperative imaging methods in patients with limb lymphedema undergoing supermicrosurgical lymphaticovenular anastomosis

OBJECTIVE

Supermicrosurgical lymphaticovenular anastomosis (LVA) is increasingly being recognized as a first-line treatment of limb lymphedema because it is minimally invasive and highly effective. Lymphoscintigraphy and indocyanine green (ICG) lymphography are the two most commonly performed diagnostic imaging examinations to establish the indication and plan the procedure for patients affected by limb lymphedema. In a small group of patients, the information between these two imaging tools can be discordant, showing different anatomical drainage pathways or the absence of drainage and dermal backflow in one examination and valid drainage pathways in the other. The purpose of this study is to examine the types of possible discrepancies between lymphoscintigraphy of the superficial system and ICG lymphography and to describe the surgical outcomes after LVA for patients presenting with such discrepancies.

METHODS

We retrospectively reviewed the data of all patients who underwent LVA for upper or lower limb lymphedema between July 2015 and July 2023. From this series, we identified a group of patients with nonconcordant imaging results from lymphoscintigraphy and ICG lymphography before lymphatic surgery. Nonconcordant findings were described in terms of "pattern discordance" and "pathway discordance." The surgical outcome was measured by the change in the mean circumference of the limb after surgery. The changes between the preoperative and postoperative limb measures were analyzed using the Student t test. P values < .05 were considered significant.

RESULTS

A total of 28 patients with limb lymphedema exhibited inconsistencies between preoperative lymphoscintigraphy of the superficial system and ICG lymphography. Among these patients, 14 experienced pattern discordance, 13 had pathway discordance, and 1 patient had both. After LVA, we observed a significant reduction in the average circumference of the affected limb in the analyzed group.

CONCLUSIONS

The discrepancy in the information between lymphoscintigraphy and ICG lymphography in the preoperative study of patients affected by limb lymphedema is rare but possible. This phenomenon is still not fully explained; however, our results suggest that it does not correlate with the outcome of supermicrosurgical LVAs.

Lymphatic Vascular Insufficiency and Focal Edema in Early Stages of Noncancer-Related Lymphedema

Introduction: Lymph flows along the lymphatics due to spontaneous contraction. However, injury and inflammation may deteriorate lymphatic' s endothelial and muscle cells and valves. In consequence, lymphatic vessels (LVs) become insufficient. Their contraction strength and rate slow down, and then lymph flow stops. Our study aimed to investigate the changes in lymph flow in early lymphedema cases. Methods and Results: In 36 patients with unilateral lymphedema stages 0 and I, we performed indocyanine green (ICG) lymphography, lymphoscintigraphy, skin water concentration, and stiffness measurement. We compared lymph flow velocity, LVs' appearance, contraction pattern, and rate between swollen and healthy limbs. ICG lymphography revealed (1) slower lymph flow after 3 minutes of foot movement; in lower calf level, lymphatics are seen in 22 (61.1%) swollen limbs compared with 36 (100%) healthy limbs (p < 0.0001); (2) dye spots in the foot (47.1%) and calves (13.9%) in swollen limbs; (3) dilated foot (41.7%) and calves' lymphatics (52.8%); (4) different patterns of lymphatics contractility with slower contractions rate and (5) higher fluorescent intensity in edema limbs. There was higher skin water concentration at foot and ankle level and higher skin stiffness in the foot. Conclusions: Our studies have shown the distortion in lymphatic function as dilatation, slower lymph flow, slower contraction rate, presence of areas with occluded lymphatics (dermal backflow in foot and calves-focal edema), and higher skin water concentration in these regions in limbs with early lymphedema. ICG lymphography can be used for the early detection of LV insufficiency, which allows early prophylactic implementation.

Current Concepts in the Management of Primary Lymphedema

Primary lymphedema is a heterogeneous group of conditions encompassing all lymphatic anomalies that result in lymphatic swelling. Primary lymphedema can be difficult to diagnose, and diagnosis is often delayed. As opposed to secondary lymphedema, primary lymphedema has an unpredictable disease course, often progressing more slowly. Primary lymphedema can be associated with various genetic syndromes or can be idiopathic. Diagnosis is often clinical, although imaging can be a helpful adjunct. The literature on treating primary lymphedema is limited, and treatment algorithms are largely based on practice patterns for secondary lymphedema. The mainstay of treatment focuses on complete decongestive therapy, including manual lymphatic drainage and compression therapy. For those who fail conservative treatment, surgical treatment can be an option. Microsurgical techniques have shown promise in primary lymphedema, with both lymphovenous bypass and vascularized lymph node transfers demonstrating improved clinical outcomes in a few studies.

Structural and functional analysis of the newt lymphatic system

Regeneration competent vertebrates such as newts and salamanders possess a weakened adaptive immune system characterized by multiple connections between the lymphatic system and the blood vascular system called lymphatic hearts. The role of lymphatic vasculature and these lymphaticovenous connections in regeneration is unknown. We used in-vivo near-infrared lymphangiography, ultra-high frequency ultrasonography, micro-CT lymphangiography, and histological serial section 3-dimentional computer reconstruction to evaluate the lymphatic territories of Cynops pyrrhogaster. We used our model and supermicrosurgery to show that lymphatic hearts are not essential for lymphatic circulation and limb regeneration. Instead, newts possess a novel intraosseous network of lymphatics inside the bone expressing VEGFR-3, LYVE-1 and CD-31. However, we were unable to show Prox-1 expression by these vessels. We demonstrate that adult newt bone marrow functions as both a lymphatic drainage organ and fat reservoir. This study reveals the fundamental anatomical differences between the immune system of urodeles and mammals and provides a model for investigating lymphatics and regeneration.

Lymphatic Intervention, the Frontline of Modern Lymphatic Medicine: Part II. Classification and Treatment of the Lymphatic Disorders

Lymphatic disorders encompass a broad spectrum of diseases involving the lymphatic system, ranging from traumatic lymphatic leaks to lymphatic malformations. Lymphatic disorders can be categorized into traumatic and non-traumatic disorders according to their etiology. These two categories may be further divided into subgroups depending on the anatomical location of the lymphatic pathology and their association with clinical syndromes. Thoracic duct embolization was a milestone in the field of lymphatic intervention that encouraged the application of percutaneous embolization techniques to treat leaks and reflux disorders in the lymphatic system. Additional access routes for embolization, including retrograde thoracic duct and transhepatic lymphatic access, have also been developed. This article comprehensively reviews a variety of options for the treatment of lymphatic disorders, from conservative management to the most recent embolization techniques.

Office-Based Lymphatic Supermicrosurgery: Supermicrosurgical Lymphaticovenular Anastomosis at an Outpatient Clinic

BACKGROUND

 Supermicrosurgical lymphaticovenular anastomosis (LVA) has become popular for the treatment of compression-refractory lymphedema. With advancement of navigation tools, LVA can be performed with more ease and safety, allowing office-based LVA at an outpatient clinic.

METHODS

 Office-based LVA was performed on patients with compression-refractory secondary extremity lymphedema by a well-experienced supermicrosurgeon (T.Y.) under local infiltration anesthesia. Indocyanine green (ICG) lymphography and vein visualizer were used to localize vessels preoperatively. A stereoscopic microscope (Leica S6E, Leica Microsystems, Germany) or a relatively small operative microscope (OPMI pico, Carl Zeiss, Germany) was used for LVA. Operative records and postoperative results were reviewed to evaluate feasibility of office-based LVA.

RESULTS

 LVAs were performed on 27 arms and 42 legs, which resulted in 131 anastomoses via 117 incisions. ICG lymphography stage included stage II in 47 limbs, and stage III in 22 limbs. Time required for one LVA procedure (from skin incision to skin closure in one surgical field) ranged from 13 to 37 minutes (average, 24.9 minutes). One year after LVA, all cases showed significant volume reduction (lymphedematous volume reduction; 0.5-23.6%, average 13.23%). No postoperative complication was observed.

CONCLUSION

 LVA can be performed with safety and effectiveness outside an operation theater. Patient selection, precise preoperative mapping, and experience of a surgeon are key to successful office-based LVA.

Lymphatic endothelial cell RXRα is critical for 9-cis-retinoic acid-mediated lymphangiogenesis and prevention of secondary lymphedema

Secondary lymphedema is a debilitating disease characterized by abnormal soft tissue swelling and caused by lymphatic system dysfunction. Despite a high prevalence of secondary lymphedema after cancer treatments, current management is supportive and there are no approved therapeutic agents that can thwart disease progression. We have previously demonstrated that 9-cis-retinoic acid (9-cisRA) has the potential to be repurposed for lymphedema as it mitigates disease by promoting lymphangiogenesis at the site of lymphatic injury. Although the efficacy of 9-cisRA has been demonstrated in previous studies, the mechanism of action is not completely understood. In this study, we demonstrate that when RXRα is specifically deleted in lymphatic endothelial cells, 9-cisRA fails to induce lymphangiogenesis in vitro and prevent pathologic progression of postsurgical lymphedema in vivo. These findings demonstrate that downstream nuclear receptor RXRα plays a critical role in the therapeutic efficacy of 9-cisRA in postsurgical lymphedema.

Spontaneous Lymph Flow Restoration in Free Flaps: A Pilot Study

BACKGROUND

Oncologic excision and trauma can be responsible for major defects and lymphedema. Free flaps are commonly used for reconstruction. We aimed to determine if lymphatic flow between flap and recipient site can be restored without lymphatic surgery.

METHODS

15 free flaps were performed in different patients in our center. Infrared-based lymphography was used to plan surgery. Indocyanine green (ICG) was injected in the flap's subdermal tissue and also at the edges of the skin defect. Circumferential lymphatic channels were marked 5 min after the ICG injection. Fluorescent images were recorded with an infrared camera system. The flap inset was obtained by putting side to side the flap markings and the recipient site markings. Infrared-based lymphography was performed on every patient one year after surgery. Spontaneous lymph flow restoration was judged positive if lymphatic connections were observed between the flap and the recipient site.

RESULTS

seven free ALT and eight DIEP flaps were performed. All ALT flaps were designed following the limb axis which is the lymphatic axiality. Spontaneous lymph flow restoration was observed for the seven ALT flaps. Eight DIEP flaps were designed upside down and one was designed following the lymph axiality. Spontaneous lymph flow restoration was only observed for the one designed following the lymph axiality.

CONCLUSIONS

designing reconstructive free flap regarding lymph axiality seems to improve spontaneous lymph flow restoration between flap and recipient site without any specific lymphatic surgery.

Lymphaticovenular Anastomosis: Superficial Venous Anatomical Approach

Background  Lymphaticovenular anastomosis (LVA) is an effective, functional treatment for limb lymphedema. This study reports an alternative surgical approach to lymphedema treatment without the use of indocyanine green mapping.

Methods  A retrospective analysis was performed on 29 consecutive lymphedema patients who underwent LVAs from January 2015 to December 2020, whereby incisions were made along the anatomy of the superficial venous systems in both upper and lower extremities around the joint areas. The evaluation included qualitative assessments and quantitative volumetric analyses.

Result  The mean number of anastomoses was 3.07, and the operative time was 159.55 minutes. Symptom improvement was recorded in 86.21% of the patients, with a mean volume reduction of 32.39%. The lymphangitis episodes decreased from 55.17% before surgery to 13.79% after surgery, and the median number of lymphangitis episodes per year decreased from 1 before surgery to 0 after surgery.

Conclusions  The superficial venous anatomical approach is an easy way to start a lymphedema practice using LVA without other advanced surgical equipment. With this reliable technique, microsurgeons can perform LVA procedures and achieve good results.

Anatomical Location of Lymphatic Pathways in the Posterior Thigh

BACKGROUND

It is necessary for treating lower extremity lymphedema to understand the lymphatic pathways in the extremities. This study aimed to clarify the anatomical locations of lymph vessels in the posterior thigh using indocyanine green (ICG) lymphography.

METHODS

Medical records of cancer survivors who underwent ICG lymphography for secondary lymphedema screening from February 2019 to November 2020 were reviewed. Nonlymphedematous limbs without dermal backflow pattern on ICG lymphography (ICG stage 0) were included. Indocyanine green (0.1 mL) was injected intradermally at 2 points in the midlateral thigh, at the levels of one third and two thirds from the popliteal fossa to the gluteal fold in a prone position. Locations of the posterior thigh collecting lymph vessels visualized by ICG lymphography were marked on the skin surface with a pen, and distances from the popliteal fossa to the collecting lymph vessels were measured at the posterior midline in percentage, with the popliteal fossa set as 0% and the gluteal fold as 100%. Based on ICG lymphography findings, the number of the collecting lymph vessels shown as linear pattern and anatomical locations at the posterior thigh midline were investigated.

RESULTS

Twenty limbs of 20 cancer survivors were included. Linear pattern was identified in all lower extremities; average number was 2.3 ± 0.7 (range, 1-3). Most collecting lymph vessels shown on ICG lymphography, 26.7% (12 of 45) lymph vessels, were located within 40% to 50% of the region, and 24.4% (11 of 45) lymph vessels within 30% to 40% of the region.

CONCLUSIONS

There are 1 or more collecting lymph vessels in the posterior thigh by midlateral thigh ICG injection, which can be addressed for posterior thigh lymphedema.

Additional Lymphaticovenular Anastomosis on the Posterior Side for Treatment of Primary Lower Extremity Lymphedema

The efficacy of lymphaticovenular anastomosis (LVA) for the treatment of primary lymphedema has been reported. Previous research suggested the efficacy of LVA on the anterior side of the lower limb, but no research has yet underlined the effectiveness of LVA on the posterior side. In the present study, we aimed to investigate the efficacy of LVA on the posterior side of the lower leg for treatment of primary lymphedema, i.e., whether further improvement of primary lower extremity lymphedema could be expected by performing LVA on the posterior side of the lower limb in addition to the LVA on the anterior side, which is usually performed. Forty-five patients with primary lower extremity lymphedema who underwent LVA twice between March 2018 and September 2020 were retrospectively investigated. Patients were classified into two groups: those who underwent LVA on the posterior side in the second operation (PoLVA group) and those who underwent LVA on the medial and anterior sides again in the second operation (MeLVA group). All patients underwent LVA on the medial and anterior sides in the first operation, but no sufficient improvement was observed. The following factors in the second operation were compared between the two groups: skin incision length, the number of anastomoses, the diameters of the lymphatic vessels, the time required for the dissection of the lymphatic vessels and veins and the reduction in volume. LVA resulted in 227 anastomoses (106 anastomoses in the PoLVA group and 121 anastomoses in the MeLVA group) in 26 patients with primary lymphedema of the lower extremities in two surgeries. The reduction in lower extremity lymphedema index was significantly greater in the PoLVA group than that in the MeLVA group (10.5 ± 4.5 vs. 5.5 ± 3.6; p = 0.008), and the number of anastomoses in the PoLVA group was significantly lower than that in the MeLVA group (3.5 ± 0.6 vs. 4.6 ± 1.0; p = 0.038). LVA on the posterior side subsequent to LVA on the medial and anterior sides resulted in the further improvement of primary lower extremity lymphedema with fewer numbers of anastomoses.

Efficacy of Microsurgical Treatment of Primary Lymphedema: A Systematic Review

INTRODUCTION

Treatment of lymphedema remains a challenging clinical problem. Lymphatic surgery has recently gained momentum as an effective method to treat both early- and late-stage disease. In particular, "physiologic" microsurgical techniques including vascularized lymph node transplant and lymphovenous bypass/anastomosis have been shown to be effective in treating even advanced lymphedema. Most published reports describe techniques and success in secondary lymphedema. Traditionally, physiologic surgery was not believed to be useful in the treatment of primary lymphedema where baseline lymphatic function is abnormal. However, recent studies have shown a benefit in these cases. The objective of this study is to evaluate outcomes and complications of physiologic microsurgical treatment for primary lymphedema.

METHODS

The electronic databases of PubMed, Scopus, and MEDLINE were searched using key words "primary lymphedema" and "surgery" (also vascularized lymph node transplant, lymphovenous bypass, microsurgery). Only human studies published between 2000 and 2021 were included. Studies that only included ablative or resection surgeries were excluded.

RESULTS

A total of 10 studies comprising 254 patients with primary lymphedema who underwent 357 physiologic microsurgical operations were included. Lymphovenous bypass comprised 88% of cases, and in the patients who underwent vascularized lymph node transplant, all but 1 flap survived. Regardless of type of operative intervention, all studies showed a statistically significant improvement in lymphedema, through either reduction in limb circumference or edema volume or improvement in quality of life.

DISCUSSION

Physiologic lymphatic surgery has shown success and improvement for patients with primary lymphedema. Based on current literature, physiologic surgical treatment of primary lymphedema should be considered when treating this patient population.

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.

Lymphaticovenous Anastomosis for Age-Related Lymphedema

INTRODUCTION

Primary lymphedema is usually caused by intrinsic disruption or genetic damage to the lymphatics but may also be the result of age-related deterioration of the lymphatics. The aims of this study were to determine the characteristics of age-related lymphedema and to assess the effectiveness of lymphaticovenous anastomosis (LVA) in its treatment.

METHODS

Eighty-six patients with primary lymphedema affecting 150 lower limbs were divided into three groups according to whether the age of onset was younger than 35 years, 35-64 years, or 65 years or older. Indocyanine green (ICG) lymphography was performed, followed by LVA surgery. ICG lymphography images were visually classified according to whether the pattern was linear, low enhancement (LE), distal dermal backflow (dDB), or extended dermal backflow (eDB). The lower extremity lymphedema (LEL) index score was calculated before and after LVA. Lymphatic vessel diameter and detection rates were also recorded.

RESULTS

In the ≥65 group, the lymphedema was bilateral in 54 patients and unilateral in 1 patient. There was statistically significant deterioration in the LEL index score with progression from the linear, LE, dDB through to the eDB pattern in the ≥65 group. The lymphatic vessel diameter was significantly greater in the ≥65 group. The rate of improvement was highest in the ≥65 group.

CONCLUSION

Age-related lymphedema was bilateral and deterioration started distally. The lymphatic vessels in patients with age-related lymphedema tended to be ectatic, which is advantageous for LVA and may increase the improvement rate.

Primary lymphoedema

Lymphoedema is the swelling of one or several parts of the body owing to lymph accumulation in the extracellular space. It is often chronic, worsens if untreated, predisposes to infections and causes an important reduction in quality of life. Primary lymphoedema (PLE) is thought to result from abnormal development and/or functioning of the lymphatic system, can present in isolation or as part of a syndrome, and can be present at birth or develop later in life. Mutations in numerous genes involved in the initial formation of lymphatic vessels (including valves) as well as in the growth and expansion of the lymphatic system and associated pathways have been identified in syndromic and non-syndromic forms of PLE. Thus, the current hypothesis is that most cases of PLE have a genetic origin, although a causative mutation is identified in only about one-third of affected individuals. Diagnosis relies on clinical presentation, imaging of the structure and functionality of the lymphatics, and in genetic analyses. Management aims at reducing or preventing swelling by compression therapy (with manual drainage, exercise and compressive garments) and, in carefully selected cases, by various surgical techniques. Individuals with PLE often have a reduced quality of life owing to the psychosocial and lifelong management burden associated with their chronic condition. Improved understanding of the underlying genetic origins of PLE will translate into more accurate diagnosis and prognosis and personalized treatment.

Magnetic resonance lymphangiography: with or without contrast?

Lymphedema is an important medical issue around the world, caused by an anomalous collection of fluid in soft tissue due to congenital malformations or stenosis or obstruction of lymphatic vessels. Magnetic resonance lymphangiography (MRL) is an emerging technique focused on noninvasive or minimally invasive imaging of lymphatics with the goal to diagnose and treat lymphedema. This review will briefly discuss lymphatic imaging starting with lymphography and radionuclide lymphoscintigraphy up to the newest methods, focusing on MRL, a rising technique, and highlighting the technical aspects fundamental for achieving high-resolution MRL.

Value of one additional injection at the root of the limb in the lymphoscintigraphic evaluation and management of primary and secondary lower-limb lymphedemas

Introduction

The classical lymphoscintigraphic investigations of lower-limb lymphatic edema [LLLE] sometimes reveal either no or few lymph nodes [LNs] at the root of the limb[s] and/or in the abdomen. The aim of the present paper is to report the results of performing one additional injection at the root of the edematous limb[s] to force the visualization of the LNs and/or to demonstrate the collateral lymphatic pathways in such patients.

Methods and findings

We retrospectively reviewed our database and found 99 patients [44 primary LLLE with 47 limbs injected and 55 with LLLE secondary to treatments for cancer with 64 limbs injected] where such an additional injection had been performed.

In the 43 LLLE patients where no LNs were seen at the end of the classical exam [15 primary LLLE and 28 secondary LLLE], the extra injection showed lymphatic drainage toward LN[s] in all except 3 and when at least one LN was seen, the injection showed lymphatic drainage in every case toward the same ipsilateral [inguinal and/or iliac] LNs [as shown by the classical injection] and/or toward additional LNs.

In 40.7% of patients, we observed one or more additional lymphatic pathways: prepubic superficial lymphatic vessels [LV] crossing the midline anteriorly toward contralateral inguinal LNs in 21 [18.9%], “posterior” LV [toward contralateral inguinal LNs and/or ipsi- or contralateral lumbo-aortic and/or para-renal LNs] in 14 [12.6%], but deep LV toward the ipsilateral common iliac LNs passing between the gluteal muscles in 32 [28.8%].

Conclusion

Our work pinpoints one limitation of classical bipedal radionuclide lymphangiography. In patients with primary and secondary LLLE where inguinal and/or iliac LNs cannot be seen on bipedal radionuclide lymphangiography, this additional injection reveals the true lympho-nodal status and shows unexpected collateral lymphatic pathways in 40% of cases. Such information is of the utmost importance in LLLE management and its acquisition is consequently recommended in these patients.

Lower limb lymphedema staging based on magnetic resonance lymphangiography

OBJECTIVE

Dermal backflow (DBF) and reduced lymphatic visualization are common findings of lymphedema on various imaging modalities. However, there is a lack of knowledge about how these findings vary with the anatomic location and severity of lymphedema, and previous reports using indocyanine green lymphography or lymphoscintigraphy show variable results. Magnetic resonance lymphangiography (MRL) is expected to clarify this clinical question due to its superior ability for lymphatic visualization. This retrospective study aimed to investigate the following: (1) Are there any characteristic patterns for DBF and lymphatics' visualization, depending on the anatomic location within lower limbs and severity of lymphedema? (2) Is it possible to classify the severity of lymphedema based on MRL findings?

METHODS

Two radiologists performed consensus readings of MRL of 56 patients (112 limbs) with lower-limb lymphedema. The frequency of visualized DBF and lymphatics was analyzed in six regions in each lower limb. The results were compared with the International Society of Lymphology clinical stages and etiology of lymphedema. Characteristic findings were categorized and compared with the clinical stage and duration of lymphedema.

RESULTS

DBF and lymphatics were observed more frequently in the distal regions than the proximal regions of lower limbs. DBF appeared more frequently as the clinical stage increased, reaching statistical significance (P < 10^-3) between stages 0 or I and II. DBF above the knee joint was rarely observed (0.48%) in early stages (0 and I) but appeared more frequently (13.5%, P < 10^-5) in stage II. Lymphatics appeared less frequently as the stage progressed, with significant differences (P < .05) between stages I and II and between II and III. The frequency of lymphatics above the knee joint decreased significantly (P < .05) between stages I and II and between II and III as the stage progressed, reaching 0% in stage III. An MRL staging was proposed and showed significant positive correlations with the clinical stage (r = 0.79, P < .01) and the duration of lymphedema (r = 0.57, P < .01).

CONCLUSIONS

MRL-specific patterns of DBF and lymphatics that depended on the site within the lower limb and clinical stage were shown. The DBF pattern differed from those observed in previous studies with other imaging techniques. The proposed MRL staging based on these characteristic findings allows new stratification of patients with lymphedema. Combined with its excellent ability to visualize lymphatic anatomy, MRL could enable a more detailed understanding of individual patient's pathology, useful for determining the most appropriate treatment.

Lymphedema secondary to melanoma treatments: diagnosis, evaluation, and treatments

Approximately 300,000 new cases of melanoma are annually diagnosed in the world. Advanced stage melanomas require sentinel lymph node biopsy (SLNB), sometimes lymph node dissections (LND). The development rate of lower extremity lymphedema ranges from 7.6% to 35.1% after inguinal SLNB, and from 48.8% to 82.5% after inguinal LND. Development rate of upper extremity lymphedema ranges from 4.4% to 14.6% after axillary LND. Lymphedema management has constantly improved but effective evaluation and surgical management such as supermicrosurgical lymphaticovenular anastomosis (LVA) are becoming common as minimally invasive lymphatic surgery. Diagnosis and new classification using indocyanine green lymphography allowing pre-clinical secondary lymphedema stage management are improving effectiveness of supermicrosurgical LVA and vascularized lymph node transfer. Lymphatic transfer with lymph-interpositional-flap can restore lymph flow after large oncologic excision even without performing lymphatic anastomosis. Since lymphatic reconstructive surgery may affect local to systemic dissemination of remnant tumor cells, careful consideration is required to evaluate indication of surgical treatments.

Simultaneous Ipsilateral Vascularized Lymph Node Transplantation and Contralateral Lymphovenous Anastomosis in Bilateral Extremity Lymphedema with Different Severities

Background

Extremity lymphedema can occur bilaterally with different severities on each side. The aim of this study is to investigate the treatment outcomes of such patients with bilateral extremity lymphedema of different severities.

Patients and Methods

Between 2013 and 2017, patients with bilateral extremity lymphedema of different severities according to the Taiwan Lymphoscintigraphy Staging (TLS) system were retrospectively reviewed. Ipsilateral vascularized lymph node transplantation (VLNT) was indicated in TLS total obstruction and contralateral lymphovenous anastomosis (LVA) in TLS partial obstruction with patent lymphatic vessels on indocyanine green lymphography. Outcomes were assessed using circumference improvement, frequency of cellulitis, and lymphedema-specific quality of life (LYMQoL) questionnaires.

Results

A total of 10 patients with bilateral extremity lymphedema with median age of 63 (range 12–75) years were included. The median symptom duration of the lymphedematous limb was 60 (range 36–168) months and 12 (range 1–60) months in the VLNT and LVA group, respectively (p < 0.05). At average follow-up of 37.5 (range 14–58) months, the average limb circumference improvement was 2.4 (range − 3.3 to 7.8) cm in the VLNT group and 2.3 (range 0.3–7) cm in the LVA group (p = 1). The median episodes of cellulitis decreased significantly from 4 to 0.5 and 1 to 0 times/year in the VLNT and LVA group, respectively (p = 0.02, p = 0.06). The overall LYMQoL score improved from 4.5 preoperatively to 7.5 postoperatively (p < 0.01).

Conclusions

Limb-specific VLNT and LVA selected by TLS effectively treated bilateral extremity lymphedema with different severities.

Lymphedema in survivors of breast cancer

The tremendous improvement of survival in patients with breast cancer can be attributed to several treatment strategies, but these strategies also lead to the occurrence of breast cancer-related lymphedema (BCRL). BRCL is regularly associated with factors such as axillary lymph node dissection and local lymph node radiotherapy and manifests as an increase of >10% in the volume of affected limbs. Being overweight or having obesity (body mass index ≥25 kg/m2), an excessive number of positive lymph nodes (>8) and capsular invasion by a tumor are additional risk factors for lymphedema. It is worth assessing the risk before surgery as this can prevent the occurrence of BCRL at the initial stage of breast cancer management. The clinical utility of many diagnostic tools and lymphedema surveillance allows early stage and even subclinical BCRL to be diagnosed, and allows real-time monitoring of the disease. The early diagnosis of BRCL allows treatment at an early stage, which is beneficial to the reduction of excess limb volume and the improvement of quality of life. At present, the major therapeutic methods of BCRL include complex decongestive therapy, pneumatic compression devices, participating in exercise, microsurgery and liposuction, each of which alleviates lymphedema effectively. No medications for treatment of BRCL have yet been developed. However, the recent findings on the success of molecular therapy in animal models may remedy this deficiency. Furthermore, the volume reduction of swollen limbs without swelling rebound by transplanting autologous stem cells has been successfully reported in some pilot studies, which may provide a new technique for treating BCRL. This review aimed to discuss the pathogenesis, clinical manifestation, risk factors, advantages and disadvantages of diagnostic tools, lymphedema surveillance and the characteristics of traditional and newly emerging BCRL treatments.

Technical pearls in lymphatic supermicrosurgery

Lymphedema is becoming a major public issue with improvement of cancer survival rate, as the disease is incurable and progressive in nature, and the number of cancer survivor with lymphedema is increasing over time. Surgical treatment is recommended for progressive lymphedema, especially when conservative therapies are ineffective. Among various lymphedema surgeries, supermicrosurgical lymphaticovenular anastomosis (LVA) is becoming popular with its effectiveness and least invasiveness. There are many technical knacks and pitfalls in LVA surgery. In preoperative evaluation, indocyanine green lymphography is recommended for considering indication and incision sites. Intraoperatively, intravascular stenting method, temporary lymphatic expansion maneuver, field-rotating retraction, and several navigation methods are useful. The most important postoperative care is immediate compression after LVA surgery. Compression is critical to keep lymphatic pressure higher than venous pressure, allowing continuous lymph-to-venous bypass flow. These technical pearls should be shared with lymphedema surgeons for better lymphedema management.

Supermicrosurgery for oncologic reconstructions

With advancement of microsurgical techniques, supermicrosurgery has been developed. Supermicrosurgery allows manipulation (dissection and anastomosis) of vessels and nerves with an external diameter of 0.5 mm or smaller. Because quality of life of cancer survivors is becoming a major issue, less invasive and functionally-better oncological reconstruction using supermicrosurgical techniques attracts attention. Conventional free flap reconstruction usually sacrifices major vessels and muscle functions, whereas supermicrosurgical free flaps can be transferred from anywhere using innominate vessels without sacrifice of major vessel/muscle. Since a 0.1-0.5 mm vessel can be anastomosed, patient-oriented least invasive reconstruction can be accomplished with supermicrosurgery. Another important technique is lymphatic anastomosis. Only with supermicrosurgery, lymph vessels can be securely anastomosed, because lymph vessel diameter is usually smaller than 0.5 mm. With clinical application of lymphatic supermicrosurgery, various least invasive lymphatic reconstruction has become possible. Lymphatic reconstruction plays an important role in prevention and treatment of lymphatic diseases following oncologic surgery such as lymphedema, lymphorrhea, and lymphocyst. With supermicrosurgery, various tissues such as skin/fat, fascia, bone, tendon, ligament, muscle, and nerves can be used in combination to reconstruct complicated defects; including 3-dimensional inset with multi-component tissue transfer.

Staging and clinical correlations of lymphoscintigraphy for unilateral gynecological cancer-related lymphedema

BACKGROUND

This study was to investigate the lymphoscintigraphy findings for the diagnosis and severity in unilateral gynecological cancer-related lymphedema (GCRL) and to correlate lymphoscintigraphy stages with the clinical findings.

METHODS

Patients with unilateral GCRL who underwent lymphoscintigraphy were staged using the presence of ileo-inguinal lymph nodes, distal-lymphatic ducts, and dermal backflow findings. Taiwan Lymphoscintigraphy Staging (TLS) was divided into three patterns and seven stages: normal drainage (L-0); partial obstruction (P-1, P-2, and P-3); and total obstruction (T4, T-5, and T-6). Correlations between clinical lymphedema severity and TLS were evaluated using analysis of variance and multivariable linear regression analyses.

RESULTS

A total of 141 patients with unilateral GCRL were divided as follows: 6 (4.3%) in normal drainage, 56 (39.7%) in partial-obstruction, and 79 (56%) in total obstruction. Cellulitis episodes, circumferential difference, and computed tomography (CT) volumetric difference were shown to be statistically different between TLS stages (P < .001 for all). Total obstruction stages were the most significant factors associated with the severity of circumferential difference (β = 19.72, 25.54, 32.42, respectively; P < .05) and CT volumetric difference (β = 36.04, 45.12, 52.78, respectively; P < .01).

CONCLUSIONS

Total lymphatic obstruction was present in 56% of unilateral GCGL. Lymphoscintigraphy stages were statistically correlated with episodes of cellulitis, circumferential difference and CT volumetric difference in unilateral GCRL.

[Application progress of indocyanine green angiography in lymphedema]

OBJECTIVE

To summarize the application progress of indocyanine green (ICG) angiography in diagnosis and treatment of lymphedema.

METHODS

The literature related to dynamic imaging tracing of lymphedema at home and abroad was reviewed extensively. And the research status and progress of ICG angiography in diagnosis and treatment of lymphedema were retrospectively analyzed.

RESULTS

ICG angiography can be used as the gold standard for the diagnosis of lymphedema at present and the classification of lymphedema severity, selection of surgical incisions and methods, and intraoperative operation. It can also be used to observe lymphatic drainage and regeneration within 1.5 cm of subcutaneous and determine the prognosis.

CONCLUSION

Compared with traditional methods, ICG angiography has more obvious advantages and value in diagnosis and treatment of lymphedema. However, it also has problems such as slow development speed and difficulty in developing deep lymphatic vessels (nodes).

Characteristics and outcomes of lymphaticovenular anastomosis in older patients with bilateral involvement versus younger patients with unilateral involvement in lower extremity lymphedema

OBJECTIVE

We have previously reported that patients with idiopathic primary lymphedema of adult onset can be classified into an older group with bilateral involvement and a younger group with unilateral involvement and that there are significant differences in the characteristics of these groups. The aims of this study were to investigate the features of these two groups further by evaluating the lymphatics while performing lymphaticovenular anastomosis (LVA) and to compare the effectiveness of LVA between the two groups.

METHODS

This study enrolled 74 patients (136 edematous legs) in whom indocyanine green (ICG) lymphography and LVA were performed. The rate of detection and the diameter of the lymphatic vessels were recorded. The lower extremity lymphedema index (the total sum of the squares of the circumference for five areas in each leg divided by the body mass index) was obtained before and 6 months after LVA. The rate of improvement in the affected lower limbs after LVA was also calculated.

RESULTS

The clinical lymphedema pattern was determined to be bilateral in 62 patients and unilateral in 12. Patients with bilateral lymphedema were significantly older than those with unilateral lymphedema (77.1 ± 7.8 years vs 55.5 ± 12.77 years; P < .01). A linear pattern was seen in 23 patients (46 legs), a low enhancement (LE) pattern in 12 patients (24 legs), a distal dermal backflow (dDB) pattern in 20 patients (40 legs), and an extended dermal backflow (eDB) pattern in 7 patients (14 legs). The lymphedema was unilateral in 12 patients (12 legs). There were significant between-group differences in lymphatic diameter in relation to lower leg area: linear (0.9 ± 0.1 mm) vs dDB (0.7 ± 0.2 mm), linear vs eDB (0.7 ± 0.2 mm), linear vs unilateral (0.5 ± 0.1 mm), LE (0.9 ± 0.2 mm) vs dDB, LE vs eDB, LE vs unilateral, and dDB vs unilateral, P < .01; and eDB vs unilateral, P < .05. There were also significant between-group differences in the rate of improvement in the lower extremity lymphedema index according to the ICG lymphography pattern and laterality: linear (10.5% ± 2.4%) vs unilateral (6.7% ± 0.6%), LE (10.4% ± 1.5%) vs unilateral, dDB (11.0% ± 1.3%) vs eDB (8.9% ± 1.5%), and dDB vs unilateral, P < .01; linear vs eDB, P < .05; and eDB vs unilateral, P < .05.

CONCLUSIONS

The lymphatic vessel diameter tended to be greater in older patients with bilateral lymphedema than in younger patients with unilateral lymphedema. The rate of detection and improvement tended to decrease with worsening of the ICG lymphography pattern. LVA is thought to be more effective in older patients with early-stage bilateral lower leg lymphedema than in their younger counterparts with late-stage unilateral lymphedema.

Flow-oriented Venous Anastomosis to Control Lymph Flow of Lymphatic Malformation

Less-invasive surgeries, such as lymphaticovenular anastomosis (LVA), are the widely accepted intervention for lymphedema. This study aimed to assess the outcomes of flow-oriented LVA modification on lymphatic malformation (LM).

METHODS

We included 19 patients diagnosed with LM mixed type or microcystic type, who came to our clinic from June 2015 to December 2017. Under general anesthesia, all patients were administered an indocyanine green lymphography injection subcutaneously. In the case of a strong inflow, the patient underwent afferent lymph vessel of LM to venous anastomosis (LMVA). Otherwise, the side wall of LMVA was performed to the cysts. Outcomes were classified into the following groups based on the size changes: treatment effect (TE) 4 = >80% reduction rate; TE 3 = 50%-80% reduction rate; TE 2 = 20%-50% reduction rate; and TE 1 = 0%-20% reduction rate.

RESULTS

All cases underwent surgery, with no case having an increased size. The results were as follows: TE 4 = 4 (21%) patients; TE 3 = 6 (32%) patients; TE 2 = 5 (26%) patients; and TE 1 = 4 (21%) patients. No case required study termination due to disease progression. Minor complication occurred in 3 cases. One vesicle increased at the labial mucosa and one wound dehiscence that epithelized within 1 month.

CONCLUSION

LMVA could be a novel, minimally invasive lymph flow-oriented surgical method for intractable LM.

Optimal Sites for Supermicrosurgical Lymphaticovenular Anastomosis: An Analysis of Lymphatic Vessel Detection Rates on 840 Surgical Fields in Lower Extremity Lymphedema Patients

BACKGROUND

Supermicrosurgical lymphaticovenular anastomosis is becoming a useful treatment option for progressive lower extremity lymphedema because of its minimal invasiveness. Finding a lymphatic vessel is a minimum requirement for lymphaticovenular anastomosis surgery, but no study has reported comprehensive analysis on factors associated with lymphatic vessel detection.

METHODS

One hundred thirty-four female secondary lower extremity lymphedema patients who underwent indocyanine green lymphography and lymphaticovenular anastomosis without a history of lymphedema surgery were included. Medical charts were reviewed to obtain clinical, indocyanine green lymphographic, and intraoperative findings. Lymphatic vessel detection was defined as positive when one or more lymphatic vessels were found in a surgical field of lymphaticovenular anastomosis. Logistic regression analysis was used to identify independent factors associated with lymphatic vessel detection.

RESULTS

Patient age ranged from 36 to 81 years, duration of edema ranged from 3 to 324 months, and body mass index ranged from 16.2 to 33.3 kg/m. Forty-eight patients (35.8 percent) had a history of radiation therapy, and 76 patients (56.7 percent) had a history of cellulitis. Lymphaticovenular anastomoses were performed in 840 surgical fields, among which lymphatic vessel detection was positive in 807 fields; the overall lymphatic vessel detection rate was 96.1 percent. Multivariate analysis revealed inverse associations in higher body mass index (OR, 0.323; p = 0.008) and the S-region/D-region on indocyanine green lymphography compared with the L-region (OR, 1.049 × 10(-8)/1.724 × 10(-9); p < 0.001/p < 0.001).

CONCLUSIONS

Independent factors associated with lymphatic vessel detection were clarified. Lower body mass index and L-region on indocyanine green lymphography are favorable conditions for finding lymphatic vessels in lower extremity lymphedema patients.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

The Relationship Between Clinical and Indocyanine Green Staging in Lymphedema

Background: Multiple staging systems for classifying the severity of lymphedema exist. The International Society of Lymphology (ISL) stage is considered standard for clinical reporting, but the relationship between clinical and functional/imaging stage remains poorly defined. Materials and Methods: We reviewed the prospectively collected data of all patients who underwent physiologic lymphedema surgery for a 3-year period by the senior author. Patients who underwent preoperative clinical staging with limb volume calculations and intraoperative indocyanine green (ICG) staging were included. Correlations were examined between ISL stage, ICG stage, and preoperative volume difference. Results: A total of 212 patients met inclusion criteria. ISL stage and preoperative volume difference had a Pearson correlation coefficient of 0.579 [p < 0.001, 95% confidence intervals, CIs (0.479-0.664)]; ICG stage and preoperative volume difference had a Pearson correlation coefficient of 0.338 [p < 0.001, 95% CIs (0.204-0.460)]; and ISL stage and ICG stage had a Pearson correlation coefficient of 0.254 [p < 0.001, 95% CIs (0.114-0.383)]. Conclusion: Clinical ISL stage does not correlate well with ICG stage in patients undergoing physiologic lymphedema surgery.

Diagnostic accuracy of bioimpedance spectroscopy in patients with lymphedema: A retrospective cohort analysis

BACKGROUND

Bioimpedance spectroscopy (BIS) is used by healthcare specialists to diagnose lymphedema. BIS measures limb fluid content by assessing tissue resistance to the flow of electric current. However, there is debate regarding the validity of BIS in diagnosing early lymphedema. Indocyanine green (ICG) lymphography has been established as the most accurate diagnostic modality to date for lymphedema diagnosis. In this retrospective study, we test the sensitivity, specificity, and diagnostic accuracy of BIS in diagnosing lymphedema by referencing its results with ICG lymphography.

METHODS

Patients presented to the University of Iowa Lymphedema Center from 2015 to 2017 were evaluated with a standardized protocol that included history and physical examination, a validated lymphedema-specific quality-of-life assessment (LYMQOL), circumference -measurement-based index, BIS, and ICG lymphography. Diagnostic accuracy of BIS was assessed using ICG lymphography as a reference test.

RESULTS

Fifty-eight patients had positive ICG lymphography results, which confirmed the diagnosis of lymphedema. ICG lymphographic findings consistently correlated with clinical examination, LYMQOL evaluation, and lymphedema indices. By contrast, BIS demonstrated a false-negative rate of 36% - 21 out of 58 patients had normal BIS readings, but a positive ICG lymphography result. The 21 false-negative results occurred in patients with early-stage disease. Sensitivity and specificity for BIS were 0.64 and 1, respectively.

CONCLUSION

BIS carries an excessively high rate of false-negative results to be dependably used as a diagnostic modality for lymphedema. ICG lymphography highly correlates with other tracking modalities, and it remains the most reliable tool for diagnosing lymphedema.

Factors Associated with Lymphosclerosis: An Analysis on 962 Lymphatic Vessels

BACKGROUND

Lymphaticovenular anastomosis is a useful treatment option for compression-refractory lower extremity lymphedema, but its efficacy depends largely on the severity of lymphosclerosis. To maximize lymphaticovenular anastomosis efficacy, it is important to elucidate factors associated with severe lymphosclerosis.

METHODS

Medical charts of 134 lower extremity lymphedema patients who underwent preoperative indocyanine green lymphography and lymphaticovenular anastomosis were reviewed to obtain data of clinical demographics, indocyanine green lymphography findings, and intraoperative findings. Based on intraoperative findings of lymphatic vessels, severity of lymphosclerosis was classified into s0, s1, s2, and s3. Severe lymphosclerosis was defined as lymphatic vessels with s3 sclerosis. Logistic regression analysis was used to identify independent factors associated with severe lymphosclerosis.

RESULTS

In total, 962 lymphatic vessels were analyzed, among which severe lymphosclerosis was observed in 97 (10.1 percent). Multivariate analysis revealed that independent factors associated with severe lymphosclerosis were higher body mass index (OR, 1.803; 95 percent CI, 1.041 to 3.123; p = 0.035), incision site in the thigh/foot compared with in the groin (OR, 2.355/4.471; 95 percent CI, 1.201 to 4.617/2.135 to 9.362; p = 0.013/p < 0.001), and S-region/D-region on indocyanine green lymphography compared with L-region (OR, 83.134/1441.126; 95 percent CI, 11.296 to 611.843/146.782 to 14149.195; p < 0.001/p < 0.001). Inverse associations were observed in positive history of radiation therapy (OR, 0.461; 95 percent CI, 0.269 to 0.788; p = 0.005).

CONCLUSIONS

Independent factors associated with severe lymphosclerosis were clarified. Indocyanine green lymphography pattern had the strongest association with severe lymphosclerosis. D-region on indocyanine green lymphography should be avoided for lymphaticovenular anastomosis.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.