Joon Pio Hong

Singapore General Hospital, Tumasik, Singapore

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Publications (86)165.73 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Reconstruction of three-dimensional lower extremity defects is challenging because the dead space should be filled and the surface defect should be covered to prevent complications. We present our experience using the vastus lateralis muscle-chimeric anterolateral thigh (ALT) free flap for reconstructing three-dimensional lower extremity defects. Methods: This report describes 12 cases of three-dimensional lower extremity defects that were treated via reconstruction using a chimeric ALT free flap between October 2010 and January 2015. The defects involved the foot (10 patients), distal lower leg (1 patient), and proximal lower leg (1 patient). The sizes of the surface defects ranged from 7.5 × 3 cm(2) to 16 × 7 cm(2) , and the sizes of the estimated dead spaces ranged from 2 × 3 cm(2) to 8 × 5 cm(2) . The skin and muscle segment sizes were also evaluated. Results: The sizes of the skin flaps ranged from 8 × 4 cm(2) to 17.5 × 8 cm(2) , and the sizes of the muscle segments ranged from 2 × 3 cm(2) to 9 × 5 cm(2) . Eleven cases exhibited full flap survival and one case exhibited partial necrosis. The follow-up periods ranged from 2 months to 38 months. We did not observe any ranges of motion limitations in the hip and knee joints of the operated leg, or any secondary complications (e.g., abscess or prolonged drainage). Conclusions: The vastus lateralis muscle-chimeric ALT free flap is a useful option for reconstructing three-dimensional lower extremity defects. © 2015 Wiley Periodicals, Inc. Microsurgery, 2015.
    Microsurgery 09/2015; DOI:10.1002/micr.22494 · 2.42 Impact Factor
  • Kyu Nam Kim · Joon Pio Hong · Chae Ri Park · Chi Sun Yoon ·
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    ABSTRACT: Background Perforator flaps have been used extensively in the field of reconstruction, and the thoracodorsal artery perforator (TDAP) flap is very popular. However, the perforator flap can be relatively bulky in some cases, depending on the defect's location. Thus, several methods have been developed to address this bulkiness, including modification of the flap elevation, application of an ultrathin flap using microdissection, and the defatting technique. However, these methods have various disadvantages, so we developed an adjustable thin TDAP flap using modification of the flap elevation and defatting technique. Methods Between January 2012 and February 2015, 13 patients underwent reconstruction of defects of their upper and lower extremities using TDAP flaps. We measured all the flap dimensions, except for thickness, because it was adjusted for the target defect. Results The mean flap size was 94 cm(2) (range: 48-210 cm(2)), and all flaps were ≤10 cm wide to facilitate primary donor-site closure. Two subjects with a history of diabetes exhibited partial flap loss, so we performed secondary skin graft surgery. Conclusions The TDAP flap elevation was modified at the superficial fascia plane, and the defatting technique was used to adjust the flap volume. This technique provided more natural contours and minimized the need for secondary debulking. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
    Journal of Reconstructive Microsurgery 08/2015; DOI:10.1055/s-0035-1563398 · 1.31 Impact Factor
  • Min Young Jang · Joon Pio Hong · Anca Bordianu · Hyun Suk Suh ·
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    ABSTRACT: A 48-year-old woman with antiphospholipid syndrome (APS) had multiple skin necrosis caused by massive bleeding and hematoma collection at the right lower leg, left thigh, and abdomen. During the first month, we did surgical debridement every 2 to 3 days with meticulous coagulation and applied negative pressure wound therapy (NPWT). Then as the base showed initial granulation, we changed the NPWT every 4 days. NPWT was used with lower pressure and cyclic mode (-40 to -75 mm Hg) to minimize trauma and to reduce the possibility of bleeding from the wounds. After 2 months of NPWT treatment, all the wounds eventually healed with secondary intension despite the patient's condition with diabetes, hemodialysis, anticoagulant use, and corticosteroid therapy. This report supports the idea that if accompanied by conservative debridement with meticulous bleeding control, application of NPWT in low pressures and close monitoring of the patient, NPWT is possible to use even in wounds of patients with risk for bleeding. © The Author(s) 2015.
    The International Journal of Lower Extremity Wounds 08/2015; 14(3). DOI:10.1177/1534734615598421 · 0.93 Impact Factor
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    ABSTRACT: Major peripheral arterial graft infection is a potentially devastating complication of vascular surgery, associated with significant mortality and high amputation rates. Autologous saphenous veins are considered optimal arterial conduits for lower extremity revascularization in infected fields, but they are often unavailable or unsuitable in these patients. This study describes two patients with major peripheral graft infection, but without available autologous veins, who underwent graft excision and cryopreserved cadaveric arterial allograft reconstruction. Although long-term graft durability is unclear because of gradual deterioration and degeneration, these findings suggest that cadaveric allografts may be good options for patients with major peripheral graft infection.
    Annals of Surgical Treatment and Research 07/2015; 89(1):51-4. DOI:10.4174/astr.2015.89.1.51
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    ABSTRACT: Although adventitial stripping has been routinely recommended and practiced during vessel preparation for microsurgical anastomoses, detailed descriptions vary regarding the adequate extent of such maneuver. We aimed to histologically clarify which components of the vessel are removed during adventitial stripping, using arterial samples harvested during microsurgical breast reconstruction. Thirteen deep inferior epigastric arteries, nine internal mammary arteries, and four thoracodorsal arteries were evaluated in each step of vessel preparation, which were (1) grossly as a vascular bundle, (2) before vessel preparation, and (3) after vessel preparation under the operative microscope. Histologic components of each sample were evaluated under light microscopy. The combined thickness of the intima and the media and the thickness of the adventitia were measured and compared. Two distinctive layers of connective tissue were observed outside the media before vessel preparation. Outer loose areolar tissue with coarse fibers was mostly removed during vessel preparation. However, the inner adventitial layer with dense, fine collagen fibers consistently remained after vessel preparation and ostensible adventitial stripping. The average thickness of this layer was comparable with that of the media. Although there was no definitive demarcation between the two differential connective tissue layers, a vasa vasorum layer was distinctly seen between the two layers. The tissue removed during standard microsurgical vessel preparation or vessel stripping is not the entire layer of the adventitia, and the inner adherent layer of adventitia with fine collagen fibers should be preserved and included in the microsuture with the intima and media during anastomosis. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
    Journal of Plastic Reconstructive & Aesthetic Surgery 06/2015; DOI:10.1016/j.bjps.2015.06.019 · 1.42 Impact Factor
  • Joon Pio Hong · Terence Goh · Sung Woo Park ·

    Plastic and Reconstructive Surgery 06/2015; DOI:10.1097/PRS.0000000000001594 · 2.99 Impact Factor
  • Kyu Nam Kim · Joon Pio Hong · Sung Woo Park · Sang Woo Kim · Chi Sun Yoon ·
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    ABSTRACT: Background When patients using the Ilizarov device need a free-flap procedure for their thigh and leg, it is difficult to isolate the major vessels as the recipient vessel due to the limited working space around the Ilizarov rings and pins. The usefulness of a perforator as the recipient vessel to allow minimally invasive surgery was investigated in this study. Methods Between October 2011 and December 2013, 77 patients using the Ilizarov device needed free flap reconstruction using an anterolateral thigh perforator flap or superficial circumflex iliac artery perforator flap. The perforator was used as a recipient vessel in 50 cases, with which end-to-end anastomosis was performed using a perforator-to-perforator approach, and major vessels were used as a recipient vessel in 27 cases (n = 20, anterior tibial vessel; n = 7, posterior vessel). Results When the perforator was used as the recipient vessel, total loss developed in one case and marginal necrosis in four cases. When the major vessel was used as the recipient vessel, whole necrosis developed in one case and marginal necrosis in two cases. The procedure increased the freedom of hand movement, decreased the recipient vessel dissection time, and reduced the recipient dissection scar. Conclusions The use of perforators as recipients overcomes the obstacles associated with the Ilizarov device and allows convenient and rapid reconstruction, with similar success as microsurgery using major vessels. Further studies are needed to address the limitations of this approach, which include perfusion physiology and the viable limit of the flap dimension. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
    Journal of Reconstructive Microsurgery 03/2015; 31(06). DOI:10.1055/s-0035-1548549 · 1.31 Impact Factor
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    ABSTRACT: Background The reconstruction of the posterior trunk remains to be a challenge as defects can be extensive, with deep dead space, and fixation devices exposed. Our goal was to achieve a tension-free closure for complex defects on the posterior trunk. Patients and Methods From August 2006 to May 2013, 18 cases were reconstructed with multiple flaps combining perforator(s) and local skin flaps. The reconstructions were performed using freestyle approach. Starting with propeller flap(s) in single or multilobed design and sequentially in conjunction with adjacent random pattern flaps such as fitting puzzle. All defects achieved tensionless primary closure. The final appearance resembled a jigsaw puzzle-like appearance. Results The average size of defect was 139.6 cm(2) (range, 36-345 cm(2)). A total of 26 perforator flaps were used in addition to 19 random pattern flaps for 18 cases. In all cases, a single perforator was used for each propeller flap. The defect and the donor site all achieved tension-free closure. The reconstruction was 100% successful without flap loss. One case of late infection was noted at 12 months after surgery. Conclusion Using multiple lobe designed propeller flaps in conjunction with random pattern flaps in a freestyle approach, resembling putting a jigsaw puzzle together, we can achieve a tension-free closure by distributing the tension to multiple flaps, supplying sufficient volume to obliterate dead space, and have reliable vascularity as the flaps do not need to be oversized. This can be a viable approach to reconstruct extensive defects on the posterior trunk. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
    Journal of Reconstructive Microsurgery 03/2015; 31(04). DOI:10.1055/s-0034-1395994 · 1.31 Impact Factor
  • Joon Pio Hong · Sung Woo Park · Dong Hoon Choi ·

    Plastic &amp Reconstructive Surgery 02/2015; 135(4). DOI:10.1097/PRS.0000000000001072 · 2.99 Impact Factor
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    ABSTRACT: Topical anesthetics, such as eutectic mixture of local anesthetics (EMLA) cream, can be applied to reduce pain before minor procedure. This trial evaluated EMLA as pretreatment for facial lacerations and compared pain, discomfort and overall satisfaction. This trial included consecutive emergency department patients ≥16 years of age who presented with simple facial lacerations. At triage, lacerations were allotted to either the routine processing group or EMLA pretreatment group according to date of admission. Initially, the emergency department doctors inspected each laceration, which were dressed with saline-soaked gauze. In the pretreatment group, EMLA cream was applied during wound inspection. The plastic surgeon then completed primary closure following the local injection of an anesthetic. After the procedure, all patients were given a questionnaire assessing pain using the 10-point visual analog scale (VAS) ("no pain" to "worst pain"). All questionnaires were collected by the emergency department nurse before discharge. Fifty patients were included in the routine processing group, and fifty patients were included in the EMLA pretreatment group. Median age was 39.9 years, 66% were male, and the average laceration was 2.67 cm in length. The EMLA pretreatment group reported lower pain scores in comparison with the routine processing group (2.4 vs. 4.5 on VAS, P<0.05), and lower discomfort scores during the procedure (2.0 vs. 3.3, P=0.60). Overall satisfaction was significantly higher in the EMLA pretreatment group (7.8 vs. 6.1, P<0.05). Pretreating facial lacerations with EMLA topical cream aids patients by reducing pain and further enhancing overall satisfaction during laceration treatment.
    Archives of Plastic Surgery 01/2015; 42(1):28-33. DOI:10.5999/aps.2015.42.1.28
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    ABSTRACT: Background: The superficial circumflex iliac artery perforator flap is a thin skin flap that can be harvested reliably and quickly from the groin. It is ideal for single-stage resurfacing of cutaneous defects. The donor site heals well and is easily concealed. The authors clarify the anatomy, simplify the flap harvest technique, and outline the modifications to expand the applications of this flap. Methods: Between January of 2011 and January of 2014, 210 superficial circumflex iliac artery perforator flaps were performed at Asan Medical Center. The flaps were used for head and neck reconstruction (n = 13), upper extremity reconstruction (n = 19), lower limb reconstruction (n = 176), and reconstruction in the trunk region (n = 2). All flaps were raised suprafascially using a free-style approach. The anatomy of the flap, the elevation technique, and the results of the reconstruction were assessed. Results: The average flap size was 86 cm2, ranging from 17.5 to 216 cm2 (mean vertical width, 6.3 cm; mean transverse length, 13.5 cm). Total flap loss occurred in 10 flaps (4.8 percent). Two patients developed complications at the donor site. Debulking surgery was performed in five patients (2.4 percent). The average follow-up period was 400 days (range, 30 to 1690 days). Conclusions: The superficial circumflex iliac artery perforator flap enables accurate resurfacing of moderate-size cutaneous defects. It is vascularly robust and versatile for use in different sites. This is the thinnest skin flap presently available and has the potential to become the new workhorse flap for resurfacing moderate-size skin defects. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.
    Plastic &amp Reconstructive Surgery 10/2014; 135(2). DOI:10.1097/PRS.0000000000000951 · 2.99 Impact Factor
  • Dong Hoon Choi · Terence Goh · Jae Young Cho · Joon Pio Hong ·
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    ABSTRACT: Distant free flaps have become a routine option for reconstruction of large, complicated facial soft tissue defects. The challenge is to find a flap that is pliable to provide good contour and function. The purpose of this paper was to evaluate the use of superficial circumflex iliac artery perforator (SCIP) flaps for facial defects.From November 2010 to June 2013, facial reconstruction was performed on 6 patients (age range, 15-79 years). The harvesting technique was modified to elevate above the deep fat, and the pedicles were taken above or just below the deep fascia. The mean size of the flap was 75.6 cm, with a thickness of 7 mm; the mean pedicle length was 4.9 cm; and the mean artery caliber was 0.7 mm. The supermicrosurgery technique was used successfully in all 6 cases. Donor sites were all closed primarily. The mean follow-up was 16.7 months.All flaps survived without flap loss, and the donor sites healed without complications including lymphorrhea. The patients were satisfied with contour and function after reconstruction.The result of these 6 cases suggested that the SCIP flap can be a reliable flap for moderate-sized to large defects in the face. The use of new instrumentation and supermicrosurgical techniques allows use of the SCIP flap reliably while providing patients with a good contour, function, and minimal donor site morbidity.
    Journal of Craniofacial Surgery 10/2014; 25(6). DOI:10.1097/SCS.0000000000001093 · 0.68 Impact Factor
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    ABSTRACT: A novel botulinum neurotoxin type A (DWP450; Daewoong Pharmaceutical, Seoul, Korea) has recently been introduced for the treatment of facial wrinkles. The efficacy of this agent has previously been demonstrated in an in vivo study using an electrophysiological protocol in a rat model. To compare the efficacy and safety of DWP450 with onabotulinumtoxinA (OBoNT) for use in the treatment of glabellar lines, we performed a multicenter, double-blind, randomized, active-controlled trial comparing DWP450 and OBoNT (Allergan Inc., Irvine, CA, USA). A total of 268 subjects with moderate to severe glabellar lines were randomized at a 1 : 1 ratio. Each patient received treatment with 20 U of study medication. Maximum frown responder rates at week 4 were measured to analyze the primary efficacy endpoint. To evaluate secondary efficacy endpoints, response rates were measured at weeks 8, 12, and 16, at maximum frown and rest. Specifically, responder rates at both maximum frown and at rest were assessed based on clinical photography. Subject degree of satisfaction and self-assessed rate of response were also measured. Adverse events (AEs) were documented to evaluate safety. Responder rate by physician-rating severity at maximal contraction at week 4 was 93.89% in the DWP450 group and 88.64% in OBoNT group. As the lower limit of the 97.5% one-sided confidence interval (– 1.53%) surpassed the – 15% threshold, we determined that DWP450 was not inferior to OBoNT. For the secondary efficacy endpoint analyses, no significant differences were observed between the two groups for any variable at any point in time. The incidences of AEs were similar for the two groups. Most of AEs were considered mild. DWP450 and OBoNT were comparable in efficacy and safety in the treatment of glabellar lines.
    International journal of dermatology 10/2014; 54(2). DOI:10.1111/ijd.12627 · 1.31 Impact Factor
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    Sangshin Lee · Inwook Jung · Seongcheol Yu · Joon Pio Hong ·
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    ABSTRACT: Background Bleeding can be a problem in wound debridement. In search for an effective hemostatic agent, we experimented with a chitosan film combined with the recombinant human epidermal growth factor (rh-EGF), hypothesizing that it would achieve effective hemostasis and simultaneously enhance arterial healing. Methods Forty-eight Sprague-Dawley rats were used, and 96 puncture wounds were made. The wounds were divided into the following four groups: treated with sterile gauze, treated with gelatin sponge, treated with chitosan, and treated with chitosan combined with rh-EGF. Immediate hemostasis was evaluated, and arterial healing was observed histologically. Results Groups B, C, and D showed a significant rate of immediate hemostasis as compared to group A (P<0.05), but there were no significant differences among groups B, C, and D. Histologically, only group D showed good continuity of the vessel wall after 1 week. It was the only group to show smooth muscle cell nuclei of the vessel wall. Conclusions We observed that chitosan has an effective hemostatic potential and the mix of rh-EGF and chitosan does not interfere with chitosan's hemostatic capabilities. We also identified enhanced healing of vessel walls when rh-EGF was added to chitosan. Further research based on these positive findings is needed to evaluate the potential use of this combination on difficult wounds like chronic diabetic ulcerations.
    Archives of Plastic Surgery 09/2014; 41(5):466-471. DOI:10.5999/aps.2014.41.5.466
  • Seong June Moon · Joon Pio Hong · So Ra Kang · Hyun Suk Suh ·
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    ABSTRACT: Background: Microsurgical technique in reconstructive surgery is important. Despite recognizing this fact, there are no systematized microsurgery training programs in Korea. The purpose of this study was to diagnose the current training programs and discuss the direction that is needed to improve them. Methods: The authors conducted a survey of graduates of a plastic surgery residency program. The questionnaire included the volume of microsurgery, training environment, area of microsurgery, department(s) performing microsurgery, and the frequency with which flaps were used. Results: Many specialties other than plastic surgery involved microsurgical procedures. The volume of microsurgery cases was disproportionate between large and small hospitals, creating an imbalance of residents' experience with microsurgical procedures. The increase in microsurgical procedures being performed has increased the number of surgeons who want to train in microsurgery. Conclusion: Increasing the number of microsurgery training programs will create more microsurgeons in Korea.
    Journal of Reconstructive Microsurgery 07/2014; 31(01). DOI:10.1055/s-0034-1383820 · 1.31 Impact Factor
  • Hyunsuk Suh · A-Young Lee · Eun Jung Park · Joon Pio Hong ·
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    ABSTRACT: Background: Closed incisional wound surgery frequently leaves dead space under the repaired skin, which results in delayed healing. The purpose of this study was to evaluate the effect of negative pressure wound therapy (NPWT) on incisional wounds with dead space after primary closure by evaluating the fluid volume through the suction drain, blood flow of the skin, tensile strength, and histology of the wounds. Methods: Bilateral 25-cm-long incisional wounds with dead space were created on the back of 6 pigs by partially removing the back muscle and then suturing the skin with nylon sutures. NPWT (experimental group) or gauze dressing (control group) was applied over the closed incision for 7 days. Analysis of the wound included monitoring the amount of closed suction drain, blood perfusion unit, tensile strength of the repaired skin, and histology of the incision site. Results: The drainage amount was significantly reduced in the experimental group (49.8 mL) compared to the control group (86.2 mL) (P = 0.046). Skin perfusion was increased in the experimental group with statistical significance compared to the control group (P = 0.0175). Collagen staining was increased in the experimental group. The tensile strength of the incision site was significantly higher in the experimental group (24.6 N at 7 days, 61.67 N at 21 days) compared to the control group (18.26 N at 7 days, 50.05 N at 21 days) (P = 0.02). Conclusion: This study explains some of the mechanism for using NPWT in closed incision wounds with dead space. It demonstrates that NPWT significantly reduces drainage amount, increases skin perfusion, increases tensile strength, and has the tendency to promote collagen synthesis for closed wound with dead space indicating enhanced healing.This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License, where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially.
    Annals of Plastic Surgery 07/2014; Publish Ahead of Print. DOI:10.1097/SAP.0000000000000231 · 1.49 Impact Factor
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    ABSTRACT: This study was conducted to evaluate the effects of foam dressing with human recombinant human epidermal growth factor (rhEGF) on the healing process in head and neck cancer patients who experience radiation-induced dermatitis (RID). Seven patients, including three with oropharyngeal, two with nasopharyngeal and one each with hypopharyngeal and laryngeal carcinoma, who underwent radiotherapy (RT) for head and neck cancer at the Asan Medical Center from March to December 2008 were prospectively included in this study. Patients who showed severe RID (more than wet desquamation) on the supraclavicular fossa or neck areas were treated by wound cleaning and debridement of granulation tissue, followed by daily rhEGF spray and foam dressing. Median time to stop exudates and reepithelialisation was 4 days. Within 14 days (median 8 days), all patients showed complete healing of RID and no longer required dressings. This new method of treatment with dressing containing rhEGF may have the potential to accelerate the healing process in patients with RID. A case-control study is needed to confirm this finding.
    International Wound Journal 06/2014; DOI:10.1111/iwj.12317 · 2.15 Impact Factor
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    ABSTRACT: Ambiguous defects on the hand and foot, especially on the fingers and toes, are still challenging to treat despite achievements in reconstruction. The purpose of this study was to evaluate the use of the posterior interosseous artery perforator flap for resurfacing intermediate-sized defects and provide adequate coverage over tendons and bones. Between October 2008 and March 2013, a total of 19 patients with soft-tissue defects on the hand or foot were treated. Flap elevation, anatomy, and clinical progress were evaluated. All flaps survived and covered the defects, which ranged in area from 12 to 45 cm2. The freestyle approach was used to harvest the flaps. The average length of the pedicle was 2.5 cm, and the pedicle was harvested without affecting the source vessel. The average diameter of the artery was 0.8 mm, and the average thickness of the flap was 3.5 mm. Anastomosis was performed either end-to-end on the perforator, or end-to-side on deep vessels. No subsequent thinning or surgical flap correction was necessary. Ambulation was allowed at 3 days postsurgery. The donor site was closed primarily to leave an acceptable donor site. A posterior interosseous artery perforator-free flap is a suitable choice for intermediate-size defects that are too large to cover using a local flap or too small for a first-line perforator flap. Up to 45 cm2 of adequate coverage can be provided using a thin posterior interosseous artery perforator-free flap that does not require additional debulking. The disadvantages of a short pedicle can be overcome using perforator-to-perforator supermicrosurgery.
    Journal of Plastic Reconstructive & Aesthetic Surgery 06/2014; 67(6). DOI:10.1016/j.bjps.2014.03.007 · 1.42 Impact Factor
  • Joon Pio Hong ·

    Journal of Reconstructive Microsurgery 05/2014; 30(7). DOI:10.1055/s-0034-1378132 · 1.31 Impact Factor
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    ABSTRACT: Objectives: IL-34 is a recently identified alternative ligand for colony-stimulating factor-1 (CSF-1) receptor. IL-34 and CSF-1 are regulators of differentiation, proliferation, and survival in mononuclear phagocytes. Here, we investigated the IL-34 serum concentration and expression in human adipose tissues and any associations with insulin resistance. Methods: We recruited 19 nondiabetic obese women, 9 type 2 diabetic women, and 27 normal-weight women. Metabolic parameters, abdominal fat distribution, serum IL-34 concentration, and IL-34 mRNA expression were measured in abdominal sc adipose tissue (SAT) and visceral adipose tissue (VAT). In addition, the expression/secretion and putative effects of IL-34 were assessed in human differentiated adipocytes. Serum IL-34 concentration was measured before and 5 to 9 months after laparoscopic Roux-en-Y gastric bypass surgery was performed on the 20 obese patients. Results: Regardless of diabetes status, obese patients demonstrated significantly higher serum IL-34 concentrations than controls. Serum IL-34 was significantly and positively correlated with insulin resistance-related metabolic parameters. IL-34 mRNA was significantly higher in VAT than SAT. IL-34 was expressed in adipocytes as well as nonadipocytes, and expression was significantly higher during adipogenesis. In differentiated adipocytes, the expression/secretion of IL-34 was enhanced by TNFα and IL-1β. In addition, IL-34 augmented fat accumulation and inhibited the stimulatory effects of insulin on glucose transport. Moreover, serum IL-34 was significantly decreased after Roux-en-Y gastric bypass-induced weight loss. Conclusion: The present study demonstrates, for the first time, that IL-34 is expressed in human adipose tissues and the circulating concentration is significantly elevated in obese patients. This suggests that IL-34 is associated with insulin resistance.
    The Journal of Clinical Endocrinology and Metabolism 04/2014; 99(7):jc20134409. DOI:10.1210/jc.2013-4409 · 6.21 Impact Factor

Publication Stats

841 Citations
165.73 Total Impact Points


  • 2015
    • Singapore General Hospital
      Tumasik, Singapore
  • 2005-2015
    • Ulsan University Hospital
      Urusan, Ulsan, South Korea
  • 2003-2015
    • University of Ulsan
      • • Asan Medical Center
      • • College of Medicine
      Ulsan, Ulsan, South Korea
  • 2006-2010
    • Asan Medical Center
      • Department of Plastic Surgery
      Sŏul, Seoul, South Korea
  • 2001-2003
    • Yonsei University
      Sŏul, Seoul, South Korea
    • Wonju Severance Christian Hospital
      Genshū, Gangwon-do, South Korea
  • 2000
    • Yonsei University Hospital
      • Department of Internal Medicine
      Sŏul, Seoul, South Korea