Yuan-Cheng Chiang

Free anterolateral thigh flap for extremity reconstruction: clinical experience and functional assessment of donor site

From August of 1995 through July of 1998, 38 free anterolateral thigh flaps were transferred to reconstruct soft‐tissue defects. The overall success rate was 97 percent. Among 38 anterolateral thigh flaps, four were elevated as cutaneous flaps based on the septocutaneous perforators. The other 34 were harvested as myocutaneous flaps including a cuff of vastus lateralis muscle (15 to 40 cm3), either because of bulk requirements (33 cases) or because of the absence of a septocutaneous perforator (one case). However, vastus lateralis muscle is the largest compartment of the quadriceps, which is the prime extensor of the knee. Losing a portion of the vastus lateralis muscle may affect knee stability. Objective functional assessments of the donor sites were performed at least 6 months postoperatively in 20 patients who had a cuff of vastus lateralis muscle incorporated as part of the myocutaneous flap; assessments were made using a kinetic communicator machine. The isometric power test of the ratios of quadriceps muscle at 30 and 60 degrees of flexion between donor and normal thighs revealed no significant difference (p > 0.05). The isokinetic peak torque ratio of the quadriceps and hamstring muscles, including concentric and eccentric contraction tests, showed no significant difference (p > 0.05), except the concentric contraction test of the quadriceps muscle, which revealed mild weakness of the donor thigh (p < 0.05). In summary, the functional impairment of the donor thighs was minimal after free anterolateral thigh myocutaneous flap transfer. (Plast. Reconstr. Surg. 107: 1766, 2001.)

Extracorporeal shock-wave therapy enhanced wound healing via increasing topical blood perfusion and tissue regeneration in a rat model of STZ-induced diabetes

Extracorporeal shock‐wave therapy (ESWT) has a significant positive effect in accelerating chronic wound healing. However, the bio‐mechanisms operating during ESWT of wounds remain unclear. This study investigated the effectiveness of ESWT in the enhancement of diabetic wound healing. A dorsal skin defect (area, 6 × 5 cm) in a streptozotocin‐induced diabetes rodent model was used. Fifty male Wistar rats were divided into five groups. Group I consisted of nondiabetic control; group II included diabetic control receiving no ESWT; group III included rats that underwent one session of ESWT (ESW‐1) on day 3 (800 impulses at 0.09 mJ/mm2) postwounding; group IV included rats that underwent two sessions of ESWT (ESW‐2) on days 3 and 7; and group V included rats that underwent three sessions of ESWT (ESW‐3) on days 3, 7, and 10. The wound healing was assessed clinically. Blood perfusion scan was performed with laser Doppler. The VEGF, eNOS, and PCNA were analyzed with immunohistochemical stain. The results revealed that the wound size was significantly reduced in the ESWT‐treated rats, especially in the ESW‐2 and ESW‐3 groups, as compared with the control (p<0.01). Blood perfusion was significantly increased after ESWT compared with the controls. Histological findings revealed a significant reduction in the topical pro‐inflammatory reaction in the ESWT group as compared with the control. In immunohistochemical stain, significant increases in VEGF, eNOS, and PCNA expressions were observed in the ESWT group, especially in the ESW‐2 and ESW‐3 groups, as compared with the control. In conclusion, treatment with an optimal session of ESWT significantly enhanced diabetic wound healing associated with increased neo‐angiogenesis and tissue regeneration, and topical anti‐inflammatory response.

Extracorporeal shock wave treatment modulates skin fibroblast recruitment and leukocyte infiltration for enhancing extended skin-flap survival

Extracorporeal shock wave (ESW) treatment has a positive effect of rescuing ischemic skin flaps. This study assessed whether ESW treatment rescues the compromised flap tissue by suppressing the apoptosis of ischemic tissue and recruiting tissue remodeling. We used a random‐pattern extended dorsal–skin‐flap (10 × 3 cm) rodent model. Thirty‐six male Sprague–Dawley rats were divided into three groups. Group I, the control group, received no treatment. Group II received one session of ESW treatment (500 impulses at 0.15 mJ/mm2) immediately after surgery. Group III received two sessions of ESW treatment, immediately and the day after the surgery. Results indicated that the necrotic area in the flaps in group II was significantly smaller than that of the flaps in group I (p<0.01). Transferase dUTP‐nick end labeling (TUNEL) analysis revealed a significant decrease in the number of apoptotic cells in group II. Hydrogen peroxide (H2O2) expression in circulation blood was significantly decreased in group II on the day after ESW treatment. Immunohistochemical staining indicated that compared with no treatment, ESW treatment could substantially increase proliferating cell nuclear antigen (PCNA), endothelial nitric oxide synthase, and prolyl 4‐hydroxylase (rPH) expression, reduce CD45 expression, and suppress 8‐hydroxyguanosine (8‐OG) expression in the ischemic zone of the flap tissue. In conclusion, ESW treatment administered at an optimal dosage exerts a positive effect of rescuing ischemic extended skin flaps. The mechanisms of action of ESWs involve modulation of oxygen radicals, attenuation of leukocyte infiltration, decrease in tissue apoptosis, and recruitment of skin fibroblasts, which results in increased flap tissue survival.

Bone marrow-derived mesenchymal stem cells enhanced diabetic wound healing through recruitment of tissue regeneration in a rat model of streptozotocin-induced diabetes.

Background: This study investigated whether bone marrow–derived mesenchymal stem cell therapy has effectiveness in the enhancement of diabetic wound healing through tissue regeneration. Methods: The authors used a dorsal skin defect (6 × 5 cm) in a streptozotocin-induced diabetes rodent model. Forty male Wistar rats were divided into four groups: group I, nondiabetic rats (controls); group II, diabetic controls receiving no mesenchymal stem cells; group III, rats receiving 1 × 107 stem cells per dose (subcutaneously administered in eight areas surrounding wound margin) on day 7; and group IV, rats receiving stem cells on days 7 and 10. Wound healing was assessed clinically. Histologic examination was performed with hematoxylin and eosin staining. CD45, Ki-67, prolyl 4-hydroxylase, epidermal growth factor, and vascular endothelial growth factor were evaluated with immunohistochemical analysis. Results: Overall clinical results showed that wound size was significantly reduced in mesenchymal stem cell–treated rats as compared with controls. Complete wound-healing time was statistically shorter in rats treated once as compared with controls (6.6 ± 1.13 weeks versus 9.8 ± 0.75 weeks; p < 0.001). It was significantly shorter in rats treated with mesenchymal stem cells twice as compared with rats treated once (5.2 ± 0.75 weeks versus 6.6 ± 1.13 weeks; p = 0.026). Histologic analysis revealed significant reduction in topical proinflammatory reaction and suppression of CD45 expression in the mesenchymal stem cell group as compared with the control group. On immunohistochemistry analysis, significant increases in epidermal growth factor, vascular endothelial growth factor, prolyl 4-hydroxylase, and Ki-67 expression were noted in the treated group as compared with the control group. Conclusions: Mesenchymal stem cells significantly enhanced diabetic wound healing. Treatment with them is associated with increases of biomarkers in tissue regeneration.

Adipose-Derived Stem Cells Accelerate Diabetic Wound Healing Through the Induction of Autocrine and Paracrine Effects.

Cell-based therapy is an attractive approach for the treatment of chronic nonhealing wounds. This study investigated whether adipose-derived stem cells (ASCs) can accelerate diabetic wound healing and traffic in the engraftment of ASCs. Dorsal full-thickness skin wound defects (6 × 5 cm) were created in a streptozotocin (STZ)-induced diabetes rodent model. Group I served as a nondiabetic normal control, group II served as a diabetic control without ASCs, and group III included rats that were injected subcutaneously in the wound margin twice with nondiabetic ASCs (1 × 107 ASCs/dose). The wound healing was assessed clinically. Histological examination and immunohistochemical analyses of periwound tissue were performed. Green fluorescence protein (GFP)+-ASCs were used to examine the engraftment of these cells after injection. XenoLight DiR-labeled ASCs were implanted to detect migration ability using an IVIS imaging system. Results revealed that complete wound healing time statistically decreased in the ASC-treated group compared to the controls (p < 0.001). Histological examination revealed the ASC-treated group showed a significant reduction in the proinflammatory reaction, with significantly increased levels of EGF, VEGF, rPH, and Ki-67 expression compared to the controls. The populations of GFP+-ASCs in circulating blood significantly increased after ASC injection compared to those of controls. Immunofluorescence staining showed GFP+-ASCs significantly accumulated in the subdermal layer of the wound margin and increased angiogenesis via vWF and VEGF expression after injection. IVIS analysis revealed ASCs could exist and home into the periwound area up to 8 weeks postimplantation. In conclusion, ASCs significantly enhanced diabetic wound healing, engrafted into the local wound tissue, and implanted into circulating blood. ASC treatment stimulated neoangiogenesis and increased tissue regeneration through paracrine and autocrine mechanisms.

Dermatofibrosarcoma protuberans in children and adolescents: Clinical presentation, histology, treatment, and review of the literature

PURPOSE Dermatofibrosarcoma protuberans (DFSP) is a rare, low-grade malignant tumor. It is characterized by aggressive local infiltration, leading to a propensity for recurrence. In children, DFSP is even less common and likely misdiagnosed or underdiagnosed. This study is a review of DFSP in the pediatric population and aims to identify factors for successful treatment. MATERIALS AND METHODS From July of 1986 to 2011, a total of 159 patients were diagnosed with dermatofibrosarcoma protuberans at Kaohsiung Chang Gung Memorial Hospital, Taiwan. Subject to the age classification of our institution, patients under the age of 18 are defined in the pediatric category, of which159 cases were identified as our research subjects. Detailed data, including demographic data, imaging studies, pathology, treatment methods, and outcomes, of these identified patients were collected, reviewed, and analyzed. RESULTS A total of 13 patients, consisting of six male and seven female patients, were identified based on our criteria. Two had the lesions noticed at birth. Most patients experienced a variable period of quiescence, followed by a rapid growth phase. All 13 patients underwent wide excisions. Post-excision reconstruction included direct closure in three cases, skin grafting in three cases, and local or free flap reconstruction in seven cases. Of 13 patients, four received postoperative radiotherapy. All patients survived without recurrence up to July 2011, with follow-up periods ranging from 20 months to 19 years. CONCLUSION Clinicians should be aware that DFSP is known to occur among children. Owing to its relatively low incidence, its presence may be confused with commoner lesions such as hemangioma, fibroma, or atrophic plaques without nodule. The confusing situation, as a result, frequently leads to delayed diagnosis. Vigilance in its diagnosis allows for treatment at manageable sizes as well as ensures complete excision. Reconstructive options, such as skin grafting, and modalities, such as adjuvant postoperative radiotherapy, are suggested to best complement each other. The former minimizes disfigurement while the latter minimizes recurrences.

Influence of neck dissection and preoperative irradiation on microvascular head and neck reconstruction-Analysis of 853 cases.

Previous neck dissection and irradiation is believed to affect the success of free tissue transfers in head and neck reconstruction, but evidence is scarce and conflicting. This study seeks to evaluate flap success rates in the presence of these two factors.

Epidemiology of Pediatric Burn Injuries in Southern Taiwan

This study comprised of 468 pediatric burn-injury cases. The patients were collected from October 1986 to December 1993 in the Burn Center at Kaohsiung Chang Gung Memorial Hospital. The population of burned children accounted for 31.3% of all 1495 patients admitted during the period. We are interested in backgrounds, causes of burn, extent of injury, place of burn, and activities during the events. The most common causes of injury were scalds (76.5%) in children under the age of 5 years (67.1%). Male was affected predominantly (61.8%). Most of the burn injuries ocurred in the winter months between October and January, and the accidents majorly happened at home (73.9%). The overall mortality was low (1.9%).

Surgical site infections among high-risk patients in clean-contaminated head and neck reconstructive surgery: concordance with preoperative oral flora.

BackgroundSalivary contamination of surgical wounds in clean-contaminated head and neck surgery with free flap reconstruction remains a major cause of infection and leads to significant morbidity. This study investigates the correlation between intraoral flora and surgical site infections (SSIs) among high-risk head and neck cancer patients undergoing resection and free flap reconstruction. MethodsOne hundred twenty-nine patients were identified as being at high risk for infective complications based on cancer stage, tumor size, comorbid factors, and extent of reconstruction. All patients had intraoral swab cultures before surgery. Patients with culture-confirmed SSI after surgery were chosen for analysis, using the &kgr; index and its 95% confidence interval for concordance analysis. All patients received clindamycin and gentamicin for antibiotic prophylaxis for 5 days. Antibiotic susceptibility testing of all isolates was obtained and analyzed. ResultsThirty-seven patients experienced SSI, or an infection rate of 28.3%, occurring at a mean of 9.3 postoperative days. The overall concordance between oral flora and SSI was fair to moderate (&kgr; index of 0.25), but detailed analysis shows a higher concordance for known and opportunistic pathogens, such as Pseudomonas aeruginosa and Enterococcus faecalis, compared to typical oral commensals. Antibiotic susceptibility tests show rapid and significant increases in resistance to clindamycin, indicating a need for a more effective alternative. ConclusionsPredicting pathogens in SSI using preoperative oral swabs did not demonstrate a good concordance in general for patients undergoing clean-contaminated head and neck surgery, although concordance for certain pathogenic species seem to be higher than for typical intraoral commensals. The rapid development of resistance to clindamycin precludes its use as a prophylactic agent.

The First Hand Allotransplantation in Taiwan: A Report at 9 Months

PurposeHand transplantations have been initiated and have been encouraged by promising results for more than 1 decade. The aim of this study was to present the first case of hand transplantation performed in Taiwan. Materials and MethodsOn September 3, 2014, we transplanted the left distal forearm and hand of a brain-dead managed 37 years to a man aged 45 years who had traumatic amputation of the distal third of his right forearm 30 years ago. The total ischemic time during the transplantation was 6 hours and 45 minutes. Immunosuppression included anti-thymocyte globulins, and methylprednisolone (Solumedrol) was used for the induction. Maintenance therapy included systemic tacrolimus, mycophenolic acid [mycophenolate mofetil (MMF)], and prednisone. A combination of systemic (tacrolimus/MMF/prednisolone) and topical immunosuppressant cream (clobetasol and tacrolimus) was applied if acute rejection occurred. Follow-up included routine posttransplant laboratory tests, skin biopsies, intensive physiotherapy, and psychological support. ResultsThe initial postoperative course was uneventful. No surgical complications were observed. Immunosuppression was well tolerated using tacrolimus, MMF, and prednisone, except for some immune-related complications. One episode of mild clinical and histological signs of cutaneous rejection was seen at 105 days after surgery. These signs disappeared after pulse therapy with Solumedrol and the topical application of immunosuppressive creams (tacrolimus and clobetasol). One infection episode occurred due to local cellulitis and axillary lymphadenopathy on day 140 and was successfully treated with antibiotics. The patient developed cytomegalovirus infection at 7 months that responded to medication. Intensive physiotherapy led to satisfactory progress in motor functioning. Sensory progress (Tinel sign) was good and reached the wrist by 3 months for the median and ulnar nerves, and could be felt in the finger tip by 9 months in response to deep pressure and light touch sensations. The patient has a lateral pinch that allows him to pick up and grip objects during daily living, although his muscle power is still insufficient. ConclusionsHand allotransplantation is technically feasible. Currently available immunosuppression methods seem to control vascularized composite tissue allotransplantation rejection. A combination of topical and systemic immunosuppressants is a useful method to prevent acute hand allotransplant rejection.