Open-Y technique for the internal mammary vein in the free abdominal flap of unilateral breast reconstruction.

BACKGROUND: In microvascular breast reconstruction, the internal mammary vein (IMV) has emerged as the most common recipient vein. The open-Y technique can increase the vessel diameter via the bifurcation site. This study aimed to investigate the open-Y technique for IMV. METHODS: The characteristics and details of the operative procedure in patients who had undergone unilateral breast reconstruction with and without the open-Y approach for the free abdominal flap were compared. Differences in IMV anastomosis site (the bifurcation of the main duct or that of the perforator branch) were also compared in patients with the open-Y technique. The open-Y technique was performed on the IMV side. RESULTS: The open-Y and conventional groups included 127 and 62 patients, respectively. The main duct diameter of IMV was significantly smaller (median 2.5 vs. 3.0 mm, P < 0.001), and the rate of right-sided anastomosis (47.2 vs. 82.3%, P < 0.001) was significantly lower in the open-Y group. When comparing the main duct and perforator groups, the branch diameter (1.8 vs. 1.0 mm, P < 0.001) and the diameter after the open-Y technique (5.0 vs. 3.9 mm, P < 0.001) were significantly higher, and the angle of bifurcation (45° vs. 60°, P = 0.007) was significantly lower in the main duct group. CONCLUSIONS: Given a small venous diameter, the open-Y technique is superior, especially for left-sided breast reconstruction. Owing to the lower angle of bifurcation and large diameter, the open-Y technique at the main duct bifurcation of IMV causes less turbulence in the blood flow. TAKE HOME MESSAGE: The open-Y technique is especially effective for left-sided breast reconstruction. Considering the lower angle of bifurcation and large diameter, the open-Y technique at the main duct bifurcation of the internal mammary vein causes less turbulence in the blood flow.

Do the Histological Differences of Soft Tissue Sarcomas Affect the Rate of Skin Defect Reconstruction?

BACKGROUND: In soft tissue sarcoma (STS) resection, flap reconstruction and/or skin grafting is frequently required. However, it is not clear whether the histological difference affects the rate of reconstruction. The present study aimed to investigate it. METHODS: This study compared in 5 classifications (105 adipocytic tumors, 102 fibroblastic tumors, 39 muscle tumors, 31 peripheral nerve sheath tumors, and 178 tumors of uncertain differentiation). In addition, the reconstruction rates of detailed tumor sites were compared. The median and case number (percentage) were calculated. RESULTS: Tumor size (adipocytic 112 mm vs fibroblastic 79 mm, muscle 72 mm, nerve 90 mm, uncertain 74 mm, P < 0.0001 in all comparisons), histological low-grade rates (adipocytic 43.8% vs uncertain 3.9%, P < 0.0001; fibroblastic 46.1% vs muscle 15.4%, P = 0.003; fibroblastic vs uncertain, P < 0.0001; nerve 19.4% vs uncertain, P = 0.003) and reconstruction rates (adipocytic 5.7% vs fibroblastic 42.2%, muscle 33.3%, nerve 32.3%, uncertain 25.8%, P < 0.0001 in all comparisons) were significantly different. In the region of lower extremity, the regions of thigh [adipocytic 1/62 (1.6%) vs fibroblastic 7/32 (21.9%), P = 0.002], and lower leg [adipocytic 1/16 (6.3%) vs fibroblastic 11/19 (57.9%), P = 0.002] were significantly different. CONCLUSIONS: In adipocytic tumors, the tumor size was significantly large; however, the skin defect reconstruction rate was significantly lower than that of the other STS. Histologically, the reconstruction rate of STS derived from superficial tissue increases, whereas the reconstruction rate derived from deep tissue such as adipocytic tumor decreases.

Fascia turnover procedure at breast reconstruction using free TRAM flap for decreasing umbilical migration.

BACKGROUND: The ideal umbilical position is midway between the two iliac crests. Some patients complained that the umbilicus position shifted from the midline after the breast reconstruction with a free muscle-sparing transverse rectus abdominis musculocutaneous (MS-TRAM) flap. We considered that the fascia of the external oblique muscle could be applied to the rectus abdominis fascia defect. This study aimed to introduce this "fascia turnover procedure" and compare the umbilical position in this procedure with that in primary fascial closure for the MS-TRAM flap of breast reconstruction. METHODS: A total of 152 patients were enrolled (80 patients with fascia turnover (+) vs. 72 patients (-)). The patients' demographics were compared. Horizontal distances (right side: a; left side: b) were measured bilaterally from the lateral abdominal wall to the center of the umbilicus. Frontal abdominal photographs were taken preoperatively (a1, b1) and postoperatively (a2, b2). The rate of umbilical migration (= | (a1 - b1) / (a1 + b1) - (a2 - b2) / (a2 + b2) | × 100%) was calculated. Because the aponeurosis of the external oblique muscle is confirmed in front of the lateral side of the anterior rectus sheath, this procedure could be performed in cases with a medial defect. RESULTS: No significant differences in the patients' demographics, including abdominal bulging rates and abdominal wall defect widths were observed between the two groups. The rate of umbilical migration showed a significant difference (median 1.78% vs. 3.70%, P < 0.001). CONCLUSIONS: This procedure could decrease the rate of umbilical migration.

Differences in Transient Fluid Retention and Lymphedema With Breast Cancer Treatment for Lymphatic Microsurgery.

BACKGROUND: Breast cancer-related lymphedema (BCRL) is a common complication. Repeated taxane-based chemotherapy has been shown to induce endothelial inflammation, leading to fluid retention. Patients with transient fluid retention only have upper limb edema without lymphatic dysfunction. Therefore, indocyanine green lymphography revealed linear findings, and lymphatic microsurgery is not required. This study aimed to investigate the difference between BCRL and fluid retention and present the indication for lymphatic microsurgery for these patients. METHODS: The study population was divided into BCRL and fluid retention groups. Age, body mass index, laterality, surgery type (lymph node, breast, or no surgery), disease stage, regional lymph node irradiation, hormone therapy, chemotherapy type (taxane- or non-taxane-based group), and treatment with trastuzumab were compared. RESULTS: The BCRL and fluid retention groups consisted of 168 and 73 patients, respectively. The BCRL group had significantly higher rates of axillary lymph node dissection (96.4%) and lymph node irradiation (51.8%) than the fluid retention group (53.4% and 24.7%, respectively; P < 0.001 for both). The fluid retention group had a significantly higher rate of taxane-based chemotherapy (100%) than the BCRL group (92.9%; P = 0.02). No significant differences in other characteristics, including treatments with hormone and trastuzumab, were observed. CONCLUSIONS: Lymphatic microsurgery should be performed after confirming the diagnosis by indocyanine green lymphography, particularly for patients with fluid retention induced by taxane-based chemotherapy. Because the generalized swelling induced by taxane-based chemotherapy is resolved 6 months after chemotherapy, we should wait at least 6 months to perform lymphatic microsurgery.

Utility of the intraflap perfusion procedure for abdominal free flap in unilateral breast reconstruction.

BACKGROUND: Heparin prophylaxis for venous thromboembolism can be used in microsurgery. If vein anastomosis is performed before the artery, heparin irrigation into the artery can be performed locally without systematic effect. This study aimed to introduce this "intraflap perfusion procedure" in autologous breast reconstruction. METHODS: Among the 220 patients with unilateral breast cancer who had received the free abdominal flap, we retrospectively compared those that had undergone the intraflap perfusion procedure (n = 108) and those who did not (n = 112). A 10 mL injection of heparinized physiological saline solution (100 units/mL) was administered into the deep inferior epigastric artery. Intraflap perfusion was performed before, during, and after vein anastomosis, without the vessel clip of the vein. Artery anastomosis was performed without the use of a vein clamp. Further, vein anastomosis was performed tightly to prevent leakage from the vein anastomosis site during artery anastomosis. RESULTS: The rates of superficial inferior epigastric vein (SIEV) superdrainage (18.5% vs. 42.0%, P < 0.001), and intraoperative flap congestion (0.9% vs. 8.0%, P = 0.01) were significantly lower in patients undergoing this procedure. There were no significant differences regarding other factors (age, BMI, laterality, comorbidities, and other operative details). CONCLUSIONS: Intraflap perfusion prevented long-term stasis at the venous anastomosis site and capillary level. It could reduce flap congestion. SIEV superdrainage was performed to manage flap congestion, particularly in patients who did not undergo this procedure. Consequently, it can be inferred that this procedure reduces the rate of superdrainage.

Correlation between abdominal visceral volume measured by a simple procedure and bulging at the abdominal free flap donor site for breast reconstruction.

BACKGROUND: Breast reconstructions using autologous abdominal tissue result in breasts with a natural shape and consistency. One of the major complications is abdominal bulging. Because of the increased abdominal wall tension, high visceral volume (not visceral fat alone) may increase the occurrence rate of abdominal bulging. A simple procedure involving CT imaging was used to assess this relationship in patients undergoing an abdominal free flap for unilateral breast reconstruction. METHODS: A total of 278 patients were enrolled in this study. The patients' demographics, the thicknesses of visceral volume were compared (Bulging (+) vs. Bulging (-)). Visceral volume was investigated based on the horizontal thickness, which was measured at the thickest part at the level of the umbilical fossa between both sides under the transverse abdominis muscles. RESULTS: Bulging (+) consisted of 39 patients (14.0%), whereas Bulging (-) included 239 patients. Patients with Bulging (+) were significantly older, had higher gestational history rate, and had thin rectus abdominis muscle. In terms of visceral volume, the Bulging (+) group had significantly higher horizontal thicknesses (median 233 mm vs. 219 mm, P < 0.001). No significant differences were observed with respect to other factors (age, BMI, history of laparotomy, and operative details). The multivariate logistic regression analysis revealed that the thickness of the rectus abdominis muscle, horizontal visceral volume, and gestational history were independently significant predictors. CONCLUSIONS: Not only the patients with thin rectus abdominis muscle but also patients with a thick horizontal visceral volume may have a higher risk of abdominal bulging.

Scarless Donor Site for Breast Reconstruction by Endoscopy-assisted Extended Latissimus Dorsi Flap plus Lipofilling.

BACKGROUND: Breast reconstruction using endoscopy-assisted latissimus dorsi (LD) flap leaves no scar on the back; however, the small amount of tissue obtained makes this procedure less practical. This study aimed to propose a new technique of endoscopy-assisted extended LD (eeLD) flap plus lipofilling, which could secure a large breast volume. METHODS: Lateral thoracic adipose tissues supplied by the thoracodorsal artery branches and the LD muscle were elevated as a single unit only through the mastectomy scar and three ports through the lateral chest. Further, fat was simultaneously injected to support the volume and shape of the breast. Changes in the volume of the reconstructed breast over time were measured using three-dimensional stereophotogrammetry. RESULTS: Overall, 15 breasts of 14 patients who underwent breast reconstruction using an eeLD flap exhibited no serious complications. On average, 281.9 ± 32.4 g of flap and 74.7 ± 19.4 ml of lipofilling were used. Within 8 weeks after the procedure, the volume of the reconstructed breast decreased to 69.5% ± 7.5% and then plateaued. Seven patients needed a subsequent session of lipofilling to acquire adequate breast volume and projection. Notably, according to the BREAST-Q back scores, patients who underwent eeLD flap were significantly more satisfied than those who underwent conventional LD musculocutaneous flap using a skin paddle on the back at the same institution (82.8 ± 9.2 vs. 62.6 ± 6.3, P < 0.0001). CONCLUSION: Despite the limitations in volume, eeLD flap plus lipofilling is advantageous because it does not leave a noticeable donor site scar.

Utilization of a partial rib-sparing procedure in microvascular breast reconstruction for preserving intercostal nerve and nipple reconstruction.

BACKGROUND: In microvascular breast reconstruction, internal mammary vessel (IMV) exposure has been performed. The preservation of intercostal nerve (ICN) is effective for preserving sensibility and decreasing postoperative pain. In nipple reconstruction, cartilage grafting is performed to provide additional support and projection. We considered that ICN preservation and costal cartilage banking could be performed simultaneously. This method was described as the "partial rib-sparing procedure." The purpose of this study was to introduce this procedure. METHODS: Surgical technique of this procedure was as follows. The second intercostal space was used. The width of the trimmed cartilage was kept within the superior half of the third costal cartilage. Soft tissue within 5 mm of the inferior border of the second rib edge was preserved to save the second ICN. The length of IMVs in the partial rib-sparing procedure and that in the total rib-sparing procedure was compared. RESULTS: The number of patients in the partial rib-sparing and total rib-sparing groups was 137 procedures and 57 procedures, respectively. The length of IMVs was significantly longer in the partial rib-sparing procedure (median 20.5 mm vs. 17.6 mm, P < 0.001). In the partial rib-sparing group, no patient complained of prolonged local pain, and chest wall contour abnormalities were absent in all cases. CONCLUSIONS: The partial rib-sparing procedure is superior, especially for patients with narrow intercostal spaces and/or patients who decide to undergo nipple reconstruction with costal cartilage. This procedure could be performed to preserve the soft tissues around the ICN and decrease the postoperative pain.

The correlation of flap blood glucose with fat necrosis of free abdominal flap for unilateral breast reconstruction.

BACKGROUND: Flap blood glucose (FBG) measurement is proposed as a monitoring technique. A cause of long-lasting fever could be derived from fat necrosis. If the findings of low FBG correlated with fat necrosis, it could predict the poor cosmetic result and a source of fever. However, this correlation remained unsolved. The purpose of this study was to clarify this correlation in breast reconstruction. METHODS: In the 180 unilateral breast cancer patients (mean age = 49.8 years) performed free abdominal flap, we retrospectively compared the group where fat necrosis occurred with the group where it did not occur (45 patients with fat necrosis vs. 135 patients without). We compared the average of FBG in each postoperative day. RESULTS: The average FBG was significantly lower in patients with fat necrosis in the second postoperative day (115.3 ± 27.3 vs. 126.3 ± 13.7 mg/dl, p = .026) and the third postoperative day (111.1 ± 22.1 vs. 118.8 ± 13.8 mg/dl, p = .036). Mean BMI and inserted total flap weight were significantly higher in patients with the fat necrosis group (24.8 vs. 22.9 kg/m2 , p = .005) (617 vs. 478 g, p = .006). The multivariate analysis revealed early FBG (OR = 0.96, p = .0002) and laterality (right side) (OR = 0.46, p = .043) were independently significant predictors. There were no significant between-group differences regarding other factors (age, systemic blood glucose, comorbidities and operative details). CONCLUSIONS: The possibility of fat necrosis was high for patients with low FBG in the early postoperative day.

Comparison of Vectra three-dimensional stereophotogrammetry measurement and tape measurement in the evaluation of perioperative volume change of the lower abdomen in association with lymphatic microsurgery.

BACKGROUND: Although microsurgical treatment for lower extremity lymphedema (LEL) can improve lower abdominal morphology, methods to evaluate the volume change of the lower abdomen have yet to be established. This study aimed to determine the accuracy and reproducibility of three-dimensional stereophotogrammetry (3DSM) in measuring the volume change in the lower abdomen. METHODS: The perioperative volume changes in the lower abdomen were estimated using tape measurement (TM) and 3DSM in 26 patients with LEL. Thirteen patients with suprapubic lymphedema underwent abdominoplasty simultaneously. Each of them underwent multiple lymphaticovenular anastomoses (LVAs), and five of them underwent vascularized lymph node transfer, simultaneously. Thirteen patients with pelvic lymphatic fluid underwent multiple LVAs. Two patients underwent this surgery twice. When assessed on the Internal Society of Lymphology scale, eight patients were Stage I, 10 patients were Stage II, four patients were late Stage II, and four patients were Stage III. The difference between the two measurement methods and reproducibility of each method were analyzed. RESULTS: During a mean follow-up period of 6 months, all patients had no postoperative complications and their chief complaint improved. The calculated reduction volume between TM and 3DSM showed a high correlation (p < .0001, r = .84). The reduction volume based on TM was significantly larger than 3DSM (991.1 ± 460.3 ml vs. 862.3 ± 333.5 ml, p = .02). The interrater ICC was 0.94 and 0.98 based on TM and 3DSM, respectively. CONCLUSION: 3DSM may be a useful method for assessment of the lower abdominal morphology due to its high accuracy and reproducibility.

Eyelid Crease Height Affects the Evaluation of Age-related Changes in the Eyelids.

Although the functional and anatomical differences between the left and right eyelids are important in the evaluation of age-related changes in the eyelids, they have not been described clearly as indications for surgical treatments. This study aimed to investigate how laterality of the eyelids affects evaluation of age-related changes. METHODS: Photographs of either one or both eyelids of 100 people were evaluated in four stages by 10 plastic surgeons. To investigate the consistency of the results between evaluations, surgeons evaluated the single-eyelid photographs (group U) or two-eyelid photographs (group B). It was investigated whether the difference in margin reflex distance 1, height of the upper eyelid crease, height of eyebrow, and levator contractile function were associated with mismatched evaluations. RESULTS: The weighted kappa coefficient for groups B and U was 0.77 (substantial agreement). One-point difference in scores was observed in 23 cases. In the multiple logistic regression analysis, only the laterality the height of the eyelid crease was significantly different between patients whose evaluations were matched and those whose evaluations were mismatched (0.9 ± 0.1 mm versus 1.7 ± 0.2 mm; OR = 1.06, 95%CI: 1.01-1.10; P = 0.01). CONCLUSIONS: Besides the structure and function of each eyelid, the laterality of the height of the eyelid crease was important in the evaluation of the age-related changes in the eyelids. This factor may be important in evaluating the aesthetic and visual impressions of age-related changes in the eyelids.

Epigenetic modifications underlie the differential adipogenic potential of preadipocytes derived from human subcutaneous fat tissue.

Ceiling culture-derived preadipocytes (ccdPAs) and adipose-derived stem cells (ASCs) can be harvested from human subcutaneous fat tissue using the specific gravity method. Both cell types possess a similar spindle shape without lipid droplets. We previously reported that ccdPAs have a higher adipogenic potential than ASCs, even after a 7-wk culture. We performed a genome-wide epigenetic analysis to examine the mechanisms contributing to the adipogenic potential differences between ccdPAs and ASCs. Methylation analysis of cytosines followed by guanine (CpG) using a 450-K BeadChip was performed on human ccdPAs and ASCs isolated from three metabolically healthy females. Chromatin immunoprecipitation sequencing was performed to evaluate trimethylation at lysine 4 of histone 3 (H3K4me3). Unsupervised machine learning using t-distributed stochastic neighbor embedding to interpret 450,000-dimensional methylation assay data showed that the cells were divided into ASC and ccdPA groups. In Kyoto Encyclopedia of Genes and Genomes pathway analysis of 1,543 genes with differential promoter CpG methylation, the peroxisome proliferator-activated receptor (PPAR) and adipocytokine signaling pathways ranked in the top 10 pathways. In the PPARγ gene, H3K4me3 peak levels were higher in ccdPAs than in ASCs, whereas promoter CpG methylation levels were significantly lower in ccdPAs than in ASCs. Similar differences in promoter CpG methylation were also seen in the fatty acid-binding protein 4 and leptin genes. In conclusion, we analyzed the epigenetic status of adipogenesis-related genes as a potential mechanism underlying the differences in adipogenic differentiation capability between ASCs and ccdPAs.

The Effect of Megakaryocytes and Platelets Derived from Human-Induced Pluripotent Stem Cells on Bone Formation.

INTRODUCTION: Platelet-rich plasma (PRP) is drawing attention as a substance that can promote bone formation. The growth factors present in PRP are stable for a long time after freeze-drying. However, the effects of PRP are inconsistent, and its effects on bone union in spinal surgery remain controversial. The immortalized megakaryocyte cell lines (imMKCLs) derived from human-induced pluripotent stem cells (hiPSCs) have been developed to produce numerous stable and clinically functional platelets. In this study, growth factors present in freeze-dried hiPSC-derived imMKCLs and platelets (iPS-MK/Plts) were evaluated, and their ability to promote bone formation was examined using a rat lumbar artificial bone grafting model. METHODS: We prepared freeze-dried iPS-MK/Plts and quantified their growth factors by enzyme-linked immunosorbent assays. Surgical grafting of artificial bone to the lumbar transverse processes was performed in 8-week-old female rats, which were divided into two groups: artificial bone graft (control) and artificial bone graft plus freeze-dried iPS-MK/Plts (iPS group). Transplantation was performed only on the left side. Eight weeks after the surgery, we captured computed tomography images and compared bilateral differences in the bone volume of the graft site in each rat. We also compared the left side/right side bone volume ratio between the two groups. RESULTS: The freeze-dried iPS-MK/Plts contained numerous growth factors. While there was no significant increase in bone volume on the transplanted side than that on the non-grafted side in the control group, bone volume significantly increased on the transplanted side in the iPS group, as evidenced by augmented mean left/right bone volume ratio of the iPS group compared with that of the control group. But the new bone observed in the iPS group was histologically normal. CONCLUSIONS: Freeze-dried hiPSC-derived MKCLs and platelets contain several stable growth factors and have the potential for promoting new bone formation.

Where does subcutaneous lymph from the chest wall flow into after mastectomy?

BACKGROUND: Changes of the lymph flow from the chest wall after mastectomy and sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (Ax) has yet to be understood. This study aimed to investigate the effect of axillary surgery on lymphatic flow from the chest wall in patients who have undergone mastectomy, including those have undergone breast reconstruction and vascularized lymph node transfer (VLNT). METHODS: Following mastectomy in 100 breasts, the directions of lymph flow from the chest wall was compared between the SLNB omission, SLNB, Ax, and Ax followed by VLNT groups using indocyanine green (ICG) lymphography in cross-sectional study. Lymph flow on the deep epigastric artery perforator (DIEP) flap was also investigated. RESULTS: Lymph flow directing to the ipsilateral axilla was observed more frequently after SLNB than Ax (48% vs. 12.5%; p = 0.005); however, no significant difference was observed in the frequency of contralateral axillary route adoption between them (8% vs. 15%; p = 0.65). In the VLNT group, lymph flow to the ipsilateral axilla was not observed at a significantly higher frequency than in the Ax group (12.5% vs. 12.5%, p = 1.00). On the transferred DIEP flap, the lymph flowed anterograde or retrograde parallel to the anatomic course of the lymphatic vessels. CONCLUSION: To visualize the direction of lymph flow of the chest following mastectomy, ICG lymphography may be useful to discern the direction in which malignant neoplasms, including lymphoma, are transported and to plan for lymph flow restoration.

Correlation of the changes in physical activity and clinical results following lymphatic microsurgery.

BACKGROUND: The physical activity (PA) of patients may change after microsurgical treatment for lower extremity lymphedema (LEL). We investigated whether PA changes perioperatively and whether it influences the treatment result. PATIENTS AND METHODS: Sixty patients with unilateral LEL (56 secondary and 4 primary) underwent lymphatic microsurgeries. Patients were divided into two groups based on improvement in International Physical Activity Questionnaire Short Form (IPAQ-SF) categories; the outcomes were compared. RESULTS: Fifty-three patients in whom linear pattern could be partially observed in indocyanine green lymphography or lymphoscintigraphy underwent lymphaticovenular anastomosis (LVA); seven patients in whom no linear pattern was observed underwent simultaneous LVA and vascularized lymph node transfer. No surgical complication was observed. The median IPAQ-SF score significantly improved from 990 (interquartile range: 231-2,376) to 1,386 (interquartile range: 940.5-4,158; p < .0001). The IPAQ-SF category improved in 22 patients (33.7%), who were categorized into the IPAQ-improved group. Improvement in excess limb volume was significantly larger in the IPAQ-improved group than that in the unimproved group (8.0 ± 4.2 vs. 3.5 ± 2.4%; p < .0001). CONCLUSION: The PA of patients may change after surgical treatment for unilateral LEL. Perioperative improvement in PA significantly correlated with the perioperative change in the excess limb volume. The change in PA is an important factor that might affect the outcome of surgical treatment for LEL. In evaluating the results of microsurgery for lymphedema, it may be necessary to consider changes in PA to avoid bias.

Internal Mammary Vein Valves: A Histological Study.

It is widely accepted that the internal mammary vein (IMV) is valveless. However, few anatomical studies are available on the presence or absence of IMV valves. To test the hypothesis that the IMV is valveless, we performed microscopic histological examination of the IMV. IMV samples were collected from 10 human fresh frozen cadavers. For a control, the small saphenous vein (SSV) was obtained. Histological stains were performed. Microscopic examination showed that a venous valve was found in 8 of 20 IMVs. The structure of the valve leaflet consisted of two parts. There was a "thick part" located near the wall of the vein that consisted of smooth muscle cells and fibers. There was also a "thin part" located near the center of the venous lumen that lacked smooth muscle cells. The size of the thick part of the IMV valve was smaller than the SSV valve, whereas there was no difference in the size of the thin part between the IMV and SSV. IMV valves exist. Our results that an IMV valve was present in less than half of IMVs and there was a small-sized valve leaflet suggest that the IMV valve may be rudimentary.

Prevention of venous reflux with full utilization of venoplasty in lymphaticovenular anastomosis.

BACKGROUND: Intraoperative retrograde blood flow from the vein to the lymphatic vessels in lymphaticovenular anastomosis (LVA) for lower extremity lymphedema (LEL) leads to poor results. This study aimed to establish a treatment strategy to control venous reflux in LVA. METHODS: A unified strategy to prevent venous reflux was used in 95 limbs (study group). Dilated perforating veins were ligated, and LVA at the small branch of the ligated vein was considered. External valvuloplasty in the small vein was performed to eliminate venous reflux pre- and post-LVA. A Y-shaped venoplasty for the relatively large vein was considered in cases without adequate-sized vein stump with a functional valve. The results were compared with the 34 limbs undergoing conventional multiple LVAs (control group). RESULTS: Intraoperative venous reflux and postoperative ecchymosis significantly decreased in the study group (0/462 anastomosis vs. 15/148 anastomosis, p < 0.0001 and 0/81 patients vs. 3/25 patients, p = 0.01, respectively). The average frequency of cellulitis during a year following LVA was significantly smaller in the study group than in the control group (0.05 ±â€¯0.03 vs 0.20 ±â€¯0.06, p = 0.04).The amount of improvement in the LEL index a year after LVA was significantly larger in the study group than in the control group (22.2 ±â€¯9.6 vs. 18.3 ±â€¯9.8, p = 0.04). CONCLUSION: Using the new strategy developed in this study, venous reflux could be completely prevented, and stable clinical results were obtained in patients with LEL. Prevention of venous reflux with full utilization of venoplasty might improve the LVA result.

Adipose-Derived Stem Cells and Ceiling Culture-Derived Preadipocytes Cultured from Subcutaneous Fat Tissue Differ in Their Epigenetic Characteristics and Osteogenic Potential.

BACKGROUND: Adipose-derived stem cells and ceiling culture-derived preadipocytes can be harvested from subcutaneous adipose tissue. Little is known about the epigenetic differences, which may contribute to differences in osteogenic potential, between these cell types. The purpose of this study was to address the osteogenic potential and underlying epigenetic status of adipose-derived stem cells and ceiling culture-derived preadipocytes. METHODS: Adipose-derived stem cells and ceiling culture-derived preadipocytes were cultured from abdominal subcutaneous fat tissues of four metabolically healthy, lean female patients. After 7 weeks of culture, cellular responses to osteogenic differentiation media were examined. To evaluate the osteogenic potentials of undifferentiated adipose-derived stem cells and ceiling culture-derived preadipocytes, two types of epigenetic assessment were performed using next-generation sequencing: DNA methylation assays with the Human Methylation 450K BeadChip, and chromatin immunoprecipitation assays for trimethylation of histone H3 at lysine 4. RESULTS: Human ceiling culture-derived preadipocytes showed greater osteogenic differentiation ability than did adipose-derived stem cells. In an epigenetic survey of the promoters of four osteogenic regulator genes (RUNX2, SP7, ATF4, and BGLAP), the authors found a general trend toward decreased CpG methylation and increased trimethylation of histone H3 at lysine 4 levels in ceiling culture-derived preadipocytes as compared to adipose-derived stem cells, indicating that these genes were more likely to be highly expressed in ceiling culture-derived preadipocytes. CONCLUSIONS: The surveyed epigenetic differences between adipose-derived stem cells and ceiling culture-derived preadipocytes were consistent with the observed differences in osteogenic potential. These results enhance the authors' understanding of these cells and will facilitate their further application in regenerative medicine.