Pathological Changes in the Lymphatic System of Patients with Secondary Lower Limb Lymphedema Based on Single Photon-Emission Computed Tomography/Computed Tomography/Lymphoscintigraphy Images.

Background: In patients with secondary upper limb lymphedema, positive correlations have been observed between the dermal back flow (DBF) type and visualization of lymph nodes around the clavicle, between the former and the lymph flow pathway type, and between the latter and the visualization of lymph nodes around the clavicle when using single photon-emission computed tomography/computed tomography/lymphoscintigraphy (SPECT-CT LSG). Methods and Results: We analyzed the associations between the visualization of inguinal lymph nodes, the lymph flow pathway type, and the DBF type using SPECT-CT LSG in 81 patients with unilateral secondary lower limb lymphedema by statistical analysis using Fisher's exact test. We revealed that the lymph flow pathways in the lower limb can be classified into nine types because the type in the lower leg is not always equal to the type in the thigh. Associations were observed between the visualization of inguinal lymph nodes and types of DBF (p < 0.01), between the types of lymph flow pathway in the thighs and visualization of the inguinal lymph nodes (p = 0.02), and between the lymph flow pathway types in the thighs and lower legs (p < 0.01). Conclusion: Detriment to the superficial lymph flow pathways in the lower limb appears to usually start from the proximal side, and deep pathways are considered to become dominant from a compensatory perspective as lymphedema severity increases.

A Novel Approach to Subcutaneous Collecting Lymph Ducts Using a Small Diameter Wire in Animal Experiments and Clinical Trials.

Background: While performing microsurgery, including lymphaticovenous anastomosis (LVA) for chronic limb lymphedema, it is a common procedure to identify the subcutaneous collecting lymph ducts with near-infrared fluorescence lymphangiography (NIR) using indocyanine green. However, due to limitations such as minimum observable depth, only a few lymphatic ducts can be identified with this procedure. Hence, we developed a new smaller-diameter "lymphatic wire" (LW) that could be inserted directly into lymphatic collecting ducts of the limbs, enabling accurate identification and localization. Methods and Results: First, used the LW on the hind limbs of 6 swine, and 36 porcine lymphatic collecting ducts were identified, the outer diameter of which varied from 0.3-0.7 mm (mean 0.41 ± 0.11 mm). We could insert the LW after creating a side opening in 30 of these ducts. We encountered no difficulties during the procedure. In the pathological examination, adverse events such as valve dysfunction and perforation were not identified. Based on the results, a clinical evaluation of the LW was performed in two patients with lower extremity lymphedema, and the LW helped us identify lymphatic ducts in the subcutaneous layer, even at the sites where the NIR had proved ineffective. Conclusion: Based on our results, we suggest that the procedure for identifying lymphatic vessels using the newly developed LW is a useful technique that can be utilized before performing a LVA for lymphedema. However, further clinical study is required to develop this device and technique, for wider clinical application in the future.

Nosological Consideration of Arterial Aneurysms Associated with Klippel-Trenaunay Syndrome.

Klippel-Trenaunay syndrome (KTS) is a rare slow-flow combined vascular malformation characterized by capillary-lymphatic-venous lesions with soft tissue overgrowth of the limbs. We report the case of a 37-year-old female KTS patient with a deep femoral arterial aneurysm. We finally diagnosed that the aneurysm had resulted from a fundamental defect in the arterial wall structure. We discuss whether the use of "aneurysm associated with KTS" is accurate and how to better classify this type of capillary-venous lesion in 17 reported KTS patients with arterial aneurysms. In this review, we describe nosological problems of arterial aneurysms associated with KTS.

Preliminary Report: The Relevance of Tumor Necrosis Factor-α in Acquired Primary Lymphedema-A Histopathological Investigation.

Background: Lymphedema includes primary lymphedema (P-LE) and secondary lymphedema (S-LE), which is a chronic progressive disease. The former group is further classified as congenital and acquired P-LE (AP-LE); its etiology is unclear, and only a few studies on its pathophysiology exist. We hypothesized that an autoimmune disease or self-inflammatory mechanism occurs in lymphatic vessels, leading to obstruction. Methods and Results: We enrolled 46 patients with lymphedema who underwent lymphaticovenous anastomosis (LVA) from January to October 2015. Collecting lymph ducts were obtained during LVA. We performed hematoxylin/eosin staining and immunostaining for LYVE-1, IL-1ß, IL-6, and TNF-α. There were no substantial histological differences between the two types of lymphedema, whereas some differences in expression of inflammatory cytokines, including interleukin (IL)-1ß and tumor necrosis factor (TNF)-α, were observed. Only a few inflammatory cells could be seen around the vessels. Although no significant differences in expression of IL-1ß were found between AP-LE and S-LE, TNF-α was more highly expressed in the smooth muscle layer in AP-LE patients than in S-LE patients. There were no significant morphological differences in the collecting ducts of lymphatic vessels between S-LE and P-LE. Nevertheless, higher levels of TNF-α accumulation were found in the thick smooth muscle layer of P-LE patients than in that of S-LE patients. Conclusion: TNF-α-related inflammation in collecting ducts of lymphatic vessels is an important characteristic of the pathology of P-LE. TNF-α inhibitors might improve symptoms of AP-LE.

Pathological changes in the lymphatic system of patients with secondary upper limb lymphoedema.

Secondary upper limb lymphoedema is usually caused by lymphatic system dysfunction. Diagnosis is primarily based on clinical features. However, there are no distinct diagnostic criteria for lymphoedema. Although conventional lymphoscintigraphy is a useful technique to diagnose the severity of lymphoedema, the resultant data are two-dimensional. In this study, we examined the pathology of lymphoedema using single photon emission computed tomography-computed tomography lymphoscintigraphy (SPECT-CT LSG), a new technique that provides 3-dimensional information on lymph flow. We observed lymph flow pathways in the subcutaneous and muscle layers of the upper limbs. A significant positive correlation was found between the dermal back flow (DBF) type and the visualization of lymph nodes around the clavicle (p = 0.000266), the type of lymph flow pathways and the visualization of lymph nodes around the clavicle (p = 0.00963), and the DBF type and the lymph flow pathway (p = 0.00766). As the severity of lymphoedema increased, the DBF appeared more distally in the upper limb and the flow into the lymph nodes around the clavicle decreased, whereas the lymph flow pathways in the muscle layer became dominant. These findings demonstrate the features of lymphoedema pathology and the functional anatomy and physiology of the lymphatic system without the need for cadaver dissection.

Clinical Course of Asymptomatic Isolated Distal Deep Vein Thrombosis of the Leg: A Single-Institution Study.

Background: The natural history of asymptomatic isolated distal deep vein thrombosis (DVT) of the leg is unclear. This study aimed to describe a 3-month and 1-year clinical course after diagnosis of asymptomatic isolated distal DVT of the leg. Methods: This study included 127 patients with asymptomatic, sonographically proven isolated distal DVT who did not receive anticoagulant therapy and were retrospectively evaluated at our hospital between May 2014 and September 2016. After 3 months and 1 year, the presence or absence of venous thromboembolism recurrence and extension of DVT toward proximal veins was sonographically confirmed. Results: At 3-month and 1-year follow-ups, 125 and 109 patients were observed, respectively. All patients showed no symptoms or findings suspecting venous thromboembolism recurrence during the observation period. However, 43 patients underwent repeat ultrasonic examination, and thrombus extension was confirmed in 2 patients. Conclusions: Asymptomatic isolated distal DVT of the leg showed good prognosis, and thus uniform anticoagulation therapy was considered unnecessary. (This is a translation of Jpn J Phlebol 2018; 29(3): 309-314.).

Real-Time Direct Evidence of the Superficial Lymphatic Drainage Effect of Intermittent Pneumatic Compression Treatment for Lower Limb Lymphedema.

BACKGROUND: Intermittent pneumatic compression (IPC) is a widely used lymph drainage therapy that can be performed at home. However, the effectiveness of IPC for lymph drainage remains unclear. The aim of this study is to investigate the real-time change in the lymph flow velocity during IPC and consider which mode and pressure are best for treating lower limb lymphedema. METHODS AND RESULTS: Eight lower left limbs of 8 healthy volunteers and 17 lower limbs of 15 secondary lymphedema patients were investigated. Indocyanine green lymphography was performed with the subject covered with a transparent six-chambered IPC garment. The IPC treatment was administered in several modes (sequential or nonsequential inflation mode, sequential or interrupted deflation mode, and under high or low pressure). Using a brightness intensity analysis software program, the real-time change in the fluorescence intensity during the treatment was recorded and graphed. The maximum inclination of the graph between 2 seconds in the inflation phase (SLOPE) and the mean SLOPE value of all subjects (average SLOPE) were calculated. The average SLOPEs of each mode of treatment were then compared. The average SLOPEs were also compared between patients with mild and moderate lymphedema. There were no significant differences among the SLOPEs in the healthy group. However, in the patient group, the average SLOPE was significantly higher in the sequential inflation mode as well as under high pressure than in the nonsequential inflation mode. On comparing the mild and moderate lymphedema groups, the average SLOPE tended to be higher in the mild group; however, the difference was not statistically significant. CONCLUSIONS: Sequential programs and high pressure resulted in a faster lymphatic flow than other modes. These results suggest that a greater treatment effect could be obtained by adjusting the mode of treatment and the pressure of IPC.

Long-term results of microscopic lymphatic vessel-isolated vein anastomosis for secondary lymphedema of the lower extremities.

PURPOSE: To evaluate the effectiveness of microscopic lymphatic vessel-isolated vein anastomosis in patients with secondary obstructive lymphedema of a lower extremity, refractory to nonoperative management. METHODS: Nine women suffered from nonpitting edema of one or both legs (11 limbs) after radical hysterectomy with postoperative irradiation for uterine cancer. The indications for this operation were repeated cellulitis and severe nonpitting edema impairing limb function. Under microscopy of 3.2 on average, the identified lymphatic vessels were anastomosed to an isolated saphenous vein using the pull-through technique with modifications. RESULTS: The follow-up period ranged from 21 to 87 months and the operation achieved excellent reduction, of more than 5 cm, in six limbs; good reduction, of 2-5 cm, in two limbs; and poor reduction, of less than 2 cm, in three limbs. The frequency of cellulitis decreased from 2.4 infections per patient per year to 0.2 infections per patient per year. CONCLUSION: These results show that microscopic lymphatic vessel-isolated vein anastomosis is a minimally invasive operation, with good long-term effects, making it the treatment of choice for intractable secondary lymphedema of the lower extremities refractory to physiotherapy.

Autologous peripheral blood mononuclear cell implantation for patients with peripheral arterial disease improves limb ischemia.

BACKGROUND: Implantation of bone marrow mononuclear cells, including endothelial progenitor cells, into ischemic limbs has been shown to improve collateral vessel formation. In the present study the safety and feasibility of autologous peripheral blood mononuclear cells (PBMNCs) implantation after granulocyte-colony stimulating factor (G-CSF)-induced mobilization was investigated in patients with severe peripheral arterial disease. METHODS AND RESULTS: Six cases were enrolled: 5 of thromboangitis obliterans and 1 of arteriosclerosis obliterans. Following administration of G-CSF (10 microg . kg(-1) . day(-1)), PBMNCs were harvested and injected intramuscularly (5 legs and 1 arm) for 2 days for the patients with ischemia of the legs. No serious adverse events related to G-CSF administration, harvest or implantation were observed during this study period. Improvement in the ankle - brachial pressure index (ABI: >0.1) was seen in 4 patients at 4 weeks and ischemic ulcers improved in 3 of 3 patients. The mean maximum walking distance significantly increased from 203 m to 559 m (p=0.031) at 4 weeks and was sustained for 24 weeks. Significant improvement was seen in physiological functioning subscale of Short Form-36. CONCLUSION: Implantation of PBMNCs collected after G-CSF administration could be an alternative to therapeutic angioplasty in patients with severe peripheral arterial disease.

Expression analyses of human endogenous retroviruses (HERVs): tissue-specific and developmental stage-dependent expression of HERVs.

The evolutional and biological roles of human endogenous retroviruses (HERVs) are less recognized compared to those of L1. In the present study, we focused on the transcriptional activity of HERVs in normal human tissues and found five HERV loci that are actively expressed in normal tissues. All but one showed tissue specificity of expression: one was expressed in stomach and small intestine and three were in placenta. We subsequently examined by TaqMan-based RT-PCR assays the temporal expression profiles of the three placenta-specific HERVs along with syncytin and syncytin 2 and observed three patterns. Syncytin and HERV-Fb showed almost constant expression through gestations. Syncytin 2 gradually decreased as pregnancy proceeded. In contrast, expression from the HERV-H/F and HERV-K(HML-6) loci increased remarkably in term placentas. Term placentas in general showed larger interindividual differences in HERV expression levels. Our results suggest that HERVs might have more diverse effects than currently thought.

Air plethysmographic assessment of external valvuloplasty in patients with valvular incompetence of the saphenous and deep veins.

PURPOSE: The indications for deep venous valvuloplasty remain controversial in patients with incompetent deep vein valves associated with primary varicose veins. The purpose of this study was to evaluate the usefulness of external femoral valvuloplasty performed simultaneously with varicose vein surgery from the standpoint of venous function determined with air plethysmography. PATIENTS AND METHODS: Thirty-one limbs of 25 patients (12 men, 13 women; mean age, 56.3 years; range, 33 to 80 years) with chronic venous insufficiency caused by valvular incompetence of both deep veins and saphenous veins were studied in a prospective, nonrandomized fashion. Descending phlebography showed moderate to severe reflux of grade 3 or 4 with Herman and Kistner classifications. Clinical severity of disease was CEAP classification 2S (in six limbs), classification 3 (in three limbs), classification 4 (in 16 limbs), classification 5 (in two limbs), and classification 6 (in four limbs). We performed superficial venous surgery alone in 14 limbs (control group), which consisted of stripping or ligation of incompetent saphenous veins and ligation of all incompetent perforators. In the remaining 17 limbs (study group), we performed superficial venous surgery simultaneously with external valvuloplasty of the femoral vein with intraoperative endoscopic observation. Venous reflux of the limbs was evaluated with air plethysmographic examination before surgery and at 1, 6, 12, and 24 months after surgery in both groups. RESULTS: Preoperative venous filling index (mean +/- standard deviation) in the control and study groups was 9.4 +/- 3.8 mL/min and 8.8 +/- 3.5 mL/min, respectively (not significant), and it decreased to 7.0 +/- 3.6 mL/min (P <.01) and 2.8 +/- 1.0 mL/min (P <.01), respectively, 1 month after surgery. Postoperative index values in the study group were significantly lower than values in the control group (P <.01), and this difference continued for more than 2 years after surgery (P <.05). After a follow-up period of 12 to 37 months (average, 25 months), the venous clinical severity score was higher in the control group (3.4 +/- 1.7) than in the study group (2.1 +/- 0.3; P <.05), and the venous disability score was higher in the control group (1.4 +/- 0.6) than in the study group (0.8 +/- 0.8; P <.05). CONCLUSION: Although further follow-up study is necessary, these results point to the functional and clinical usefulness of femoral valvuloplasty performed simultaneously with varicose vein surgery in patients with moderate to severe deep venous reflux. The venous filling index obtained with air plethysmography is an excellent predictor of the clinical severity of the disease and of postoperative clinical results.