Cherng-Kang Perng

In Vivo Angiogenesis Effect of Porous Collagen Scaffold with Hyaluronic Acid Oligosaccharides

BACKGROUND Tissue engineering is a promising solution for tissue defect repair. A key problem, however, is how to keep the engineered tissue alive after implantation. The ideal scaffold for tissue engineering would be biocompatible and biodegradable and, more importantly, would exhibit good interaction with endothelial cells to promote angiogenesis. MATERIALS AND METHODS Three different scaffolds were synthesized: collagen/hyaluronic acid (HA) (MW 6.5K), collagen/HA (MW 220K), and collagen only. The synthesized collagen/HA scaffold was analyzed for water content, pore size, and HA content. An animal model for in vivo tissue construct angiogenesis was developed using the inferior epigastric skin flap of mice and perfusion of quantum dots; the average fluorescence intensity per unit area was calculated and correlated with vessel density from histologic examination. RESULTS The pore size is not statistically different among the three groups and the HA content is not statistically different between the two collagen/HA groups. The fluorescence intensity of the collagen/HA (MW 6.5K) group is increased at day 14, 21, and 28, and is significantly higher than in the other groups. Similar results were also obtained from histologic immunohistochemistry studies. CD31-stained vessels were found co-localized with QD fluorescence and these newly formed vessels were identified at day 14 in the collagen/HA (MW 6.5K) group and increased significantly at day 21 and 28. CONCLUSION This study showed that collagen scaffolds with short-chain HA (MW 6.5K) revascularize faster than those with long-chain HA (MW 220K) and collagen only. The results of the new animal model for studying scaffold angiogenesis are compatible with the conventional methods of immunostaining and histological examination.

Vascular Complications and Free Flap Salvage in Head and Neck Reconstructive Surgery: Analysis of 150 Cases of Reexploration.

Introduction Despite the excellent reliability of free tissue transfer, flap failure is devastating, and in addition to patient morbidity, it may increase hospital stay and associated costs. Previous studies have evaluated factors related to flap salvage, regarding the operative strategy for flap salvage surgery. The present study aimed to share our experience of reexploration and describe operative standards dealing with vascular thrombosis. Methods We retrospectively reviewed 150 (of 1258) free flaps for head and neck reconstruction that showed signs of vascular compromise at our institution during a 13-year period between 2002 and 2015. Patient demographics, including sex, age, premorbid health status, personal history, indication for reexploration, flap type, and number of recipient vessels, were analyzed. Days between the end of initial surgery and salvage surgery were also recorded. The incidence of postsalvage complications (hematoma formation, wound dehiscence, and infection requiring surgical intervention) and the overall flap survival were recorded. Results Of the 150 flaps, 87 flaps had evident arterial or venous thrombosis; 34 of these failed and required a second free flap or pedicle flap reconstruction. The remaining 53 were successfully salvaged. Although vascular thrombosis was found to be a major contributing factor in flap loss, no significant differences in any factor were found between patients with salvageable flaps and those with unsalvageable flaps. Conclusions Vascular thrombosis is a major contributing factor in flap loss. The incidence of venous thrombosis is higher, but arterial thrombosis may be more severe. Improvements in the surgical technique and perioperative management are highly reliable. We believe that strict models of flap monitoring; well-trained, dedicated staff; and immediate reexploration will potentially further improve flap survival and optimize the quality of life.

Experience With the Use of Free Fasciocutaneous Flap in Through-and-Through Cheek-Buccal Defect Reconstruction: Surgical Outcome and Quality of Life Analysis.

BackgroundThrough-and-through cheek-buccal soft tissue defects usually require fasciocutaneous flaps for reconstruction. However, no ideal flap has been established for reconstruction. MethodsA retrospective chart review of head and neck reconstruction performed at Taipei Veterans General Hospital between 2003 and 2012 was conducted. Surgical outcomes and quality-of-life assessments between different fasciocutaneous flaps were collected and compared. ResultsEighty-five patients received a free anterolateral thigh flap, and 25 patients received a free forearm flap. The flap success rates were 96.4% for the free anterolateral thigh flap and 96% for the free forearm flap. Appearance, swallowing, and speech were less satisfactory in long-term follow-up; and recurrent tumor, flap size (>100 cm2), oral commissure involvement, and long hospital stay (>40 days) were associated with unsatisfactory quality of life. ConclusionsFree fasciocutaneous flap can result in acceptable success rates, but patient satisfaction with appearing, swallowing, and speech function was relatively low after reconstruction. Tumor status (primary or recurrent), flap size, oral commissure involvement, and length of hospital stay are the main factors that affect quality of life.

Risk Factors of Surgical Intervention in the Management of Venomous Snakebite in Northern Taiwan

Venomous snakebites are not uncommon in Taiwan, and the snake venom causes both systemic and local effects. Petechiae, edema, swelling, ecchymosis, necrosis of the skin and subcutaneous tissue, and necrotizing fasciitis could be seen locally, and surgical intervention may be needed to deal with these problems. However, functional impairment and limb loss were still sometimes inevitable. We retrospectively reviewed medical records of 118 patients bitten by venomous snakes from Jan. 1999 to Dec. 2004, and risk factors of surgical intervention were studied. The relationship of the need of surgical intervention and snake species, clinical grading, symptoms, and other associating factors were analyzed. Surgery was needed in 16 of 118 patients(13.5%)bitten by venomous snakes, 7 by Taiwan cobra, 5 by Taiwan habu, 1 by green habu, 1 by hundred pacer, and 2 by unknown snake. Risk factors of surgical intervention were Taiwan cobra snakebite(7/14)and delayed given of antivenom. Taiwan cobra snakebite was found with higher risk of local necrosis and infection. Therefore, more surgical interventions were needed in this group of patients, and early antivenom given and broad spectrum antibiotics coverage were recommended

Extracorporeal membrane oxygenation support may be a lifesaving modality in patients with burn and severe acute respiratory distress syndrome: Experience of Formosa Water Park dust explosion disaster in Taiwan

BACKGROUND Extracorporeal membrane oxygenation (ECMO) has been reported to improve outcomes in patients with refractory respiratory failure. These successful experiences have stimulated interest in using ECMO as a potential therapy for patients with acute pulmonary failure resulting from burn and inhalation lung injury. Current literature has supported the use of ECMO in critically-ill, pediatric burn patients. On the other hand, it is controversial to apply ECMO in adult burn patients, and the evidence is limited by the shortcomings of small sample size. We share our successful experience of ECMO treatment in the casualties of the Formosa Water Park Dust Explosion Disaster. METHODS We investigated the data from the dust explosion event, which happened on June 27, 2015, in New Taipei, Taiwan. The medical records of five patients with severe acute respiratory distress syndrome receiving ECMO were evaluated. RESULTS The mean study subject age was 21.8 years, with a mean total body surface area burned of 82.9%. The average time to ECMO setup was 48.6 days. Survivors and non-survivors averaged four days and 77.7 days, respectively. The overall mortality rate was 40%. Three survivors were discharged without any ECMO-related complications or pulmonary sequelae after one year of follow up. CONCLUSIONS ECMO may be a lifesaving modality for burn patients with severe lung injury who are nonresponsive to maximal medical management, especially for young patients with early ECMO intervention.

Fractional CO 2 laser contributes to the treatment of non-segmental vitiligo as an adjunct therapy: a systemic review and meta-analysis

The treatment of stable non-segmental vitiligo is often challenging, which new therapies are being searched. Multiple clinical trials have proposed the benefits and safety of using fractional carbon dioxide (CO2) laser as an adjunct therapy to conventional treatments. This study aimed to evaluate the safety and efficacy of fractional carbon dioxide laser as a combination therapy to conventional treatments in patients with stable non-segmental vitiligo. A literature search using PubMed, EMBASE, and the Cochrane Library was performed for comparative studies among vitiligo patients treated with additional fractional CO2 laser. Clinical outcomes in the selected studies were compared, and a meta-analysis was performed via Review Manager version 5.3, according to the PRISMA guidelines. Six studies with a total of 184 patches/patients were included in the present meta-analysis. The combination therapy group had significantly superior results than that of the control group (≥ 75% re-pigmentation, risk ratio [RR] 2.80, 95% confidence interval [CI] 1.29–6.07; ≥ 50% re-pigmentation, RR 2.26, 95% CI 1.23–5.9; < 25% re-pigmentation, RR 0.57, 95% CI 0.43–0.75). Limitations of the study included the small number of studies and sample size, inadequate blinding of participants, and variation between therapy protocols. Meta-analysis revealed that using fractional CO2 laser in combination with conventional treatments is efficient and safe, and may be considered as an adjunct therapeutic option for patients with refractive non-segmental vitiligo.

Intraoperative Mapping of the Subfascial Plexus Using the Transillumination Method for Head and Neck Reconstruction with Free Style Anterolateral Thigh Flaps

Abstract Without well recognizing the vascular territories of the perforator, surgery might damage the pedicle and diminish flap survival. This study described a transillumination method for intraoperative mapping of the subfascial plexus of the perforator in the head and neck reconstruction with an anterolateral thigh (ALT) flap and also compared the perioperative outcomes and complications of the method with those of the conventional two‐pedicle ALT flap. Between January 2011 and December 2017, 26 patients who underwent head and neck reconstruction with ALT flaps were evaluated as follows: 13 underwent the transillumination method (case group), and 13 (age‐ and sex‐matched) underwent standard two‐pedicle flap procedures (control group). Demographic factors, diagnosis, flap size, recipient site, perioperative data, and postoperative complications were compared between the two groups. There was no significant difference in age, sex, diagnosis, recipient sites, and flap size between the case and control groups. Regarding the perioperative outcomes, the harvesting time was significantly shorter in the case group than in the control group (60 vs. 100 minutes, p < 0.001). The operative time was shorter in the case group than in the control group, but this difference was not statistically significant (300 vs. 420 minutes, p = 0.058). The transillumination method can allow plastic surgeons to easily identify the perforator vascular plexus of the ALT flap, which facilitates intraoperative flap design in head and neck reconstruction.

Chronic Radiodermatitis over Left Elbow and Left Chest Wall after Cadiac Angiography-A Case Report

Background:Cardiac angiography is one of the most common diagnostic and therapeutic procedures for heart diseases. It produces high dose of radiation exposure. The subsequent skin injury might result in radiodermatitis.Aim and Objectives:Radiodermatitis after cardiac angiography has been reported over axilla or upper back areas. In this paper, we present a rare case of radiodermatitis with relenting pain over both left elbow and left lateral chest wall after 3 repeated and prolonged cardiac angiography.Materials and Methods:A 64-year-old man received 3 times of cardiac angiography in 3 years for his coronary arterial disease. Percutaneous coronary angioplasty was intended during the third cardiac angiography which resulted in prolonged procedure for more than 4 hours. A skin lesion, measured 10 X 8 cm2, was noted with a central ulcer for one year after the last cardiac angiography. Despite various local wound treatments, the wound healed poorly, and the pain persisted. Total excision of the skin lesion and reconstruction with a pedicled radial forearm flap was performed with favorable result. A separative chronic ulceration developed over left chest wall half a year later. Successful treatment was achieved with total excision of the ulcerative lesion and local flap coverage. For both lesions, histopathological findings revealed dermal and epidermal necrosis with fibrosis, which was compatible with chronic radiation injury and secondary ulceration.Results:The painful sensation relieved after the surgery, and the patient had full recovery after the reconstruction in two years follow-up.Conclusion:Chronic radiodermatitis after cardiac angiography with interventions is uncommon, but the incidence is rising with the increasing number and complexity of these procedures. In this case report, excision of ulcerative lesions with flap coverage provided symptom relief and good wound healing. (J Taiwan Soc of Plast Surg 2011; 20: 309∼315)

Outcome Evaluation of Skin-Grafted Free Muscle Flap versus Reverse Sural Fasciocutaneous Flap in Soft Tissue Reconstruction of Weight-Bearing Heel

There were eighteen patients received soft tissue reconstruction of weight-bearing heel at our institution in past 10 years. Eleven patients received skin-grafted free muscle flaps and seven received reverse sural fasciocutaneous flaps. The etiology of the wounds were osteomyelitis (55.6%), necrotizing fasciitis (11.1%), trauma (11.1%) and tumor resection (11.1%). The patients who received free muscle flap surgery were younger (average 45.2 y/o), had much larger wound size (12.4x 6.6cm^2) longer operative time, and less hospital days. The complication rate was comparable between these two modalities. They all achieved a considerable successful rate and limb salvage rate. The muscle flap group presented as higher percentage in resuming walking and working. It also had better functional score but higher chance of chronic ulcer. In consideration of weight-bearing heel reconstruction, the skin-grafted muscle flap seems to be the first choice. In elder patient or patient who is not suitable for long operative time, reverse sural fasciocutaneous flap is probably an alternative with acceptable successful rate but less functional result is expected.

Malignant Salivary Gland Tumors-Ten Years Clinicopathological Experience at VGH-Taipei

Malignant salivary gland tumors are uncommon and demonstrate wide diversity of histopathological types and biological behaviors. We report the experience in the management of patients with malignant salivary gland tumors and review the outcome of treatment in an effort to identify significant factors of survival, local recurrence and distant metastases. The age (p=0.002), stage (p＜0.001), histological grade (p=0.020), resection margin (p=0.036) and the presence of neck metastases, local recurrences and distant metastases (p＜0.001) were significantly associated with poorer survival. Local recurrences was correlated with stage (p＜0.001), histology grade (p=0.042), and resection margin (p=0.026). Distant metastases depended on stage (p=0.006), especially tumor size, and facial palsy (p=0.030). The treatment of salivary gland malignancies remains primarily surgical. However, the benefits of combined modality therapy with regard to overall survival await prospective clinical trials.