• Archives of Reconstructive Microsurgery
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• v.9 no.1
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• pp.27-36
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• 2000

February 1995 to September 1999, authors have experienced seven cases of infected nonunion of tibial fractures with associated soft tissue injury and skin defect, and have accomplished union in all cases by free vascularized fibular graft. All grafts healed with no radiographic evidence of bone necrosis or resorption and have been able to treat large bony defect and skin defect simultaneously. In this study, five cases of vascularized free fibular osteocutaneous flap transfer and two cases of free fibular graft are reported. All of seven cases were infected nonunion of tibia. The results were obtained as follows 1) The mean duration of the radiologic bone union was average 5.3months. 2) Grafted fibular has been hypertrophied, average 10.6 months. 3) In five cases of preservation of posterior cortex of tibia, bony union and hypertrophy of grafted bone were earlier than that two cases of complete segmental resection of tibia. 4) In two cases which only free vascularized fibular graft were performed because achievement of cutaneous flap was failed, authors found that soft tissue defect was filled with granulation tissue and split-thickness skin graft was possible over the granulation tissue after 3 weeks postoperatively.

• Journal of Chest Surgery
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• v.25 no.12
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• pp.1508-1515
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• 1992

Between 1975 and 1992, forty five patients with trachea stenosis received tracheoplasty for relief of obstruction. The causes of airway problem are brain contusion[19 cases, 40%], cerebrovascular disease[3 cases, 7%], drug intoxication[8 cases, 18%], psychotic problem[2 cases, 4%], trachea tumor[3 cases, 7%], adult respiratory distress syndrome[9 cases, 20%] and direct trauma[1 case, 2%]. Direct causes of trachea stenosis were complications of tracheostomy[36 cases, 80%], complications of nasotracheal intubation[5 cases, 11%], tumor[3 cases, 6%] and trauma[1 case, 2%]. Thirty one patients underwent the sleeve resection and end-to-end anastomosis. Five patients performed a wedge resection and end-to-end anastomosis. Forteen patients received the Montgomery T-tube for relief of airway obstruction. Four patients have done simple excision of granulation tissue. Two, subglottic stenosis patients were received Rethi procedure[anterior division of cricoid cartilage, wedge partial resection of lower thyroid cartilage and Montgomery T-tube molding] and the other subglottic stenosis patient underwent permanent trachea fenestration. Including cervical flexion in all patients postoperatively, additional surgical techniques for obtain tension-free anastomosis were hyoid bone release technique in two cases, and hilar mobilization, division of inferior pulmonary ligament and mobilization of pulmonary vessel at the pericardium were performed in one case. Cervical approach was used in 39 cases, cervicomediastinal in 12 cases and transthoracic in one case. Complications of tracheoplasty were formation of granulation tissue at the anastomosis site[3 cases], restenosis[9 cases], trachea-innominate artery fistula[2 cases], wound infection[2 cases], separation of anastomosis[2 cases], air leakage[3 cases], injury to a recurrent laryngeal nerve[temporary 8 cases, permanent 2 cases] and hypoxemia[1 case]. Surgical mortality for resection with primary reconstruction was 6.7%, with one death due to postoperative respiratory failure and two deaths due to tracheo-innominate artery fistula.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.20 no.1
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• pp.36-41
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• 2009

Background and Objectives: Topical administration of mitomycin-C (MMC) has been reported to reduce or delay scar formation in airway surgery. However, it is not infrequent to experience recurrent stenosis or adhesion of operative wound even after a meticulous MMC application during the laryngeal surgery. Therefore we aimed to evaluate the effectiveness of repeated postoperative MMC applications and the technical feasibility of MMC applications to the laryngeal wound at an outpatient clinic. Methods: We reviewed medical records of 13 consecutive patients who received office-based MMC applications after laryngeal airway surgery at Samsung Medical Center, Seoul, Korea. The patients were grouped into 3 categories according to the site of surgical wound and the purpose of MMC application; group I : supraglottic stenosis (n=5), group II : cordectomy and arytenoidectomy site granulation prevention (n=3), Group III : laryngeal web prevention (n=5). Outcomes in each group and adverse effects of repeated MMC applications were evaluated. Results: Office-based MMC application was successfully performed one to four times with a week interval for each patient. No significant complications were observed except slightly decreased mucosal wave in one female patient who received 4 times of MMC application at the anterior commissure of vocal fold. Repeated MMC applications at the outpatient clinic resulted in wide or acceptable supraglottic airway in group I, clean wound healing without granulation formation in group II, and negligible or no web formation at the anterior commissure in group III. Conclusion : Office-based topical administration of MMC to the larynx was technically feasible. Postoperative repeated MMC applications were effective to reduce recurrent stenosis or adhesion of supraglottic structures, to prevent granuloma formation after laser arytenoidectomy and glottic web formation after anterior commissure resection.

• Archives of Plastic Surgery
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• v.35 no.4
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• pp.393-399
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• 2008

Purpose: Chronic infected wounds sustained over 4 weeks with exposed tendon or bone are difficult challenges to plastic surgeons. Vacuum assisted closure (VAC) device has been well used for the management of chronic wounds diminishing wound edema, reducing bacterial colonization, promoting formation of granulation tissue and local blood flow by negative pressure to wounds. But Commercial ready-made VAC device might have some difficulties to use because of its high expenses and heavy weight. So we modified traditional VAC device with silver dressing materials as topical therapeutic agents for control of superimposed bacterial wound infection such as MRSA, MRSE and peudomonas. Methods: We designed the modified VAC device using wall suction, 400 cc Hemovac and combined slow release silver dressing materials. We compared 5 consecutive patients' data treated by commercial ready-made VAC device(Group A) with 11 consecutive patients' data treated by modified VAC device combined with silver dressing materials(group B) from September 2004 to June 2007. Granulation tissue growth, wound discharge, wound culture and wound dressing expenses were compared between the two groups. Results: In comparison of results, no statistical differences were identified in reducing rate of wound size between group A and B. Wound discharge was significantly decreased in both groups. Modified VAC device with silver dressing materials showed advantages of convenience, cost effectiveness and bacterial reversion. Conclusion: In combination of modified VAC device and silver dressing materials, our results demonstrated the usefulness of managing chronic open wounds superimposed bacterial infection, cost effectiveness compared with traditional VAC device and improvement of patient mobility.

• Archives of Plastic Surgery
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• v.39 no.4
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• pp.317-321
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• 2012

Background Many topical hemostatics are widely applied for bleeding control. They can be classified into two categories according to their mechanism of action on the clotting cascade in a biologically active or passive manner. Passive hemostatics include cellulose and gelatin. We performed an experimental study to compare the effect of passive hemostatics in wound healing by applying them to a rectus abdominis muscle defect of white mice. Methods Surgicel is a sterile absorbable knitted fabric prepared by the controlled oxidation of regenerated cellulose. Spongostan is an absorbable hemostatic gelatin sponge. In 30 mice, a $1{\times}1$ cm defect was created on the rectus abdominis muscle and the materials were applied in three ways: control group, cellulose (Surgicel) group, gelatin (Spongostan) group. For the histologic analysis, biopsies were performed at 3 and 28 days. Results After 3 days, the cellulose group showed limited granulation formation with acute inflammatory reactions similar to the control group. At the 28th day, moderate amounts of granulation tissue formation was observed with milder inflammatory reactions than the control group. In the gelatin group, after 3 days, gelatin remnants were observed surrounded by severe inflammatory changes. After 28 days, the same quantity of gelatin remnants could be still observed. Conclusions This study suggests that cellulose is associated with minimal morbidity in wound healing, while the use of gelatin shows severe adverse tissue reactions with delayed wound healing. Consequently, cellulose is better than gelatin when considering wound healing.

• Applied Chemistry for Engineering
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• v.10 no.2
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• pp.183-189
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• 1999

Zinc-based sorbents for $H_2S$ removal were prepared. The reactivity of sorbents was investigated by the successive cycles of sulfidation-regeneration at $650^{\circ}C$ in a fixed bed reactor. The desulfurization sorbents were prepared with granulation method to produce a spherical pellet with good attrition resistance. The fresh and reacted sorbents were characterized by X-Ray Diffraction (XRD) and X-Ray Photoelectron Spectroscopy (XPS) and the characteristics of sorbents on calcination conditons were analysed by Mercury Porosimetery and BET. The reactivity of sorbents decreased as the number of sulfidation-regeneration cycle increased. It is due to the zinc loss and the increase of the diffusion resistance by sintering, cracking and spalling of sorbents at the high temperature.

• Restorative Dentistry and Endodontics
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• v.14 no.2
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• pp.49-64
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• 1989

The purpose of this study was to evaluate the effect of several materials on the healing process of apical wound. Sixteen mandibular premolars obtained from 4 healthy dogs were used for this study. Under general anesthesia, the pulpal chamber of each tooth was opened and the pulps were extirpated. The root canals were then instrumented with H-file and irrigated with physiologic saline solution ; the apices were purposely perforated and enlarged with the engine K-reamer. In the experimental groups, apical wounds were filled with one of calcium hydroxide, hydroxylapatite, and tricalcium phosphate materials, mixture of each materials and physiologic saline solution, with a lentulo spiral. In the control group, apical wounds were not filled with any material. All the root canals were filled by the lateral condensation technique with gutta-percha cone and ZOE sealer. The access opening of all the teeth were closed with amalgam. On the 10, 20, 40 and 60th day after experiment, experimental animals were sacrificed. Segments of jaws, each containing one tooth, were fixed in 10% formalin solution and decalcified in Plank-Rychlo solution. The specimens were embedded in paraffin and serially sectioned to an average thickness of $6{\mu}m$. The sections were stained by hematoxylin-eosin and Masson's trichrome stain method and examined under light microscope. The results were as follows : 1. In the experimental groups, the new bone formations were observed in apical wounds. 2. Fourty days later, apical wounds were healed by granulation tissue in the experimental groups, but were not healed by granulation tissue in the control group, and the healing process of experimental groups were more rapid than that of control group. 3. Sixty days later, chronic inflammation disappeared in the experimental groups, and the materials used showed biologic affinity to the periapical tissue. 4. In all the groups, the resorption of cementum appeared on the 10th and 20th day after experiment, and the deposition of cementum appeared on the 40th and 60th day after experiment, especially showing narrowness of apical foramen due to newly formed cementum in calcium hydroxide group. 5. Calcum hydroxide and tricalcium phosphate particles were gradually resolved, but hydroxylapatite particles were not resolved through the experimental period.

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.461-474
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• 1993

This study was performed to estimate the effect of plaque control on the progress of the repair pattern of the alveolar bone surface after bone surgery. In this experiment six mongrel dogs were used, four of them were as experimental group and others were as control. In the case of experimental group, dental floss ligature was tied over the neck of crown for permiting of plaque accumulation during one week before surgery and oral hygiene procedures were not performed. In control group, all the surgical intervention was done as same procedure with experimental except oral hygiene program. After surgery plaque was controlled during one week with using the chlorhexidine brushing. Animals were sacrificed at 1,2,4,6 weeks after osseous surgery. The results were as follows : 1. The alveolar bone defects were covered with regenerated epithelium at one week, matrix change of granulation tissue on subcutaneous area was observed, and new bone formation was initiated from the surface of the bone defects. 2. The connective tissue arrangement revealed more dense, new bone formation by osteoblasts was active at 2 weeks and proliferation of gingival epithelium and alveolar bone tissue were evident at 4 weeks, and almostly recovered to normal condition at 6 weeks. 3. In experimental group, inflammatory reaction was persistent in early stage and bone repair was delayed compared to control group. 4. In control group, matrix change of granulation tissue was initiated from one week, regeneration of gingival epithelium and maturation of subcutaneous conective tissue and new bone formation were evident at 2 weeks, so almost normal bone regeneration was observed at 4,6 weeks.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.4
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• pp.862-870
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• 2011

In this paper, we introduce a new topology of Radial Basis Function-based Polynomial Neural Networks (RPNN) that is based on a genetically optimized multi-layer perceptron with Radial Polynomial Neurons (RPNs). This study offers a comprehensive design methodology involving mechanisms of optimization algorithms, especially Fuzzy C-Means (FCM) clustering method and Particle Swarm Optimization (PSO) algorithms. In contrast to the typical architectures encountered in Polynomial Neural Networks (PNNs), our main objective is to develop a design strategy of RPNNs as follows : (a) The architecture of the proposed network consists of Radial Polynomial Neurons (RPNs). In here, the RPN is fully reflective of the structure encountered in numeric data which are granulated with the aid of Fuzzy C-Means (FCM) clustering method. The RPN dwells on the concepts of a collection of radial basis function and the function-based nonlinear (polynomial) processing. (b) The PSO-based design procedure being applied at each layer of RPNN leads to the selection of preferred nodes of the network (RPNs) whose local characteristics (such as the number of input variables, a collection of the specific subset of input variables, the order of the polynomial, and the number of clusters as well as a fuzzification coefficient in the FCM clustering) can be easily adjusted. The performance of the RPNN is quantified through the experimentation where we use a number of modeling benchmarks - NOx emission process data of gas turbine power plant and learning machine data(Automobile Miles Per Gallon Data) already experimented with in fuzzy or neurofuzzy modeling. A comparative analysis reveals that the proposed RPNN exhibits higher accuracy and superb predictive capability in comparison to some previous models available in the literature.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.276-279
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• 2007

A 2-year-old male, 3 kg body weight Japanese Chin was injured in the automobile accident three months ago. The dog became antebrachiocarpal joint instability, and performed pancarpal arthrodesis using 3 K-wires in localanimal hospital. But, the result was failure. Therefore the dog was referred to Chonbuk Animal Medical Center, Chonbuk National University. In physical examination, right carpal joint instability, knuckling sign and pain were evident. In radiography, sclerosis was observed on the 4th carpal bone. Complete blood count (CBC), serum chemistry and urinalysis finding were within reference ranges. Pancarpal arthrodesis was re-performed using 7-hole plate. However, mild skin and muscle defects was appeared by skin tension of extremity. We expected that granulation would fill the defect, but inflammation was continued on the lesions for 3 days. So, operation which is filling it was done by using the muscle flap and tubed skin flap. The donor muscles were flexor carpi radialis and superficial digital flexor muscles. After 7 days, the muscle flap was survived, but tubed skin flap was necrosed. After 20 days, the skin defect was substituted with granulation tissues. The flexor carpi radialis muscle and superficial digital flexor muscle transposition can be a useful procedure for reconstructing soft tissue defects in the carpal and metacarpal areas.