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Seung-Kyu Han

Publications and source records attributed to Seung-Kyu Han.

16 recordsLinked to original sources
PubMed2006

The effect of human bone marrow stromal cells and dermal fibroblasts on angiogenesis.

BACKGROUND: A cell therapy methodology for angiogenesis using fibroblasts has already been developed. Bone marrow stromal cells, which contain mesenchymal stem cells, have a low rate of immunity-assisted rejection and are capable of expanding profoundly in culture. Therefore, these cells offer several advantages for transplantation over mature cells. The aim of this study was to compare the angiogenic activity of bone marrow stromal cells with that of fibroblasts. METHODS: For in vitro study, cultured human bone marrow stromal cells and dermal fibroblasts were seeded onto 96-well culture plates. After 1, 3, and 5 days, the levels of the basic fibroblast growth factor and vascular endothelial growth factor were compared. For in vivo study, porous polyethylene disks were loaded with bone marrow stromal cells, fibroblasts, or no cells and then implanted in the backs of rats. At three time intervals ranging from 1 to 3 weeks, the microvascular density was measured. RESULTS: In the in vitro study, the basic fibroblast growth factor levels in the bone marrow stromal cell group were 47, 89, and 68 percent higher than in the fibroblast group at each time interval (p < 0.05). The vascular endothelial growth factor levels of the bone marrow stromal cell group were seven, 12, and 12 times higher than those of the fibroblast group (p < 0.05). In the in vivo study, there was little difference in the microvascular density among the three groups by the second week. However, the 3-week specimens showed a significantly greater difference. The microvascular density averaged 52.88, 26.12, and 17.50 for the bone marrow stromal cell, fibroblast, and no-cell groups, respectively. CONCLUSION: These results suggest that bone marrow stromal cells may possibly be used as a replacement for fibroblasts for angiogenesis.

Adult↗
PubMed2006

Factors affecting nostril shape in Asian noses.

BACKGROUND: Because few studies have been performed regarding the factors affecting nostril shape in Asian noses, this study was undertaken to determine them. METHODS: A total of 20 fresh cadaver noses were classified into horizontal and vertical types and dissected. The authors investigated the presence, volume, and insertions of muscles surrounding the ala; alar cartilage shape; footplate segment ratio of the medial crus; and the characteristics of tip supporting structures. RESULTS: Horizontal nostril types had larger dilator naris anterior and posterior muscular components. In particular, the insertion of the dilator naris posterior muscle extended to the midpoint between the alar base and the nasal tip, whereas that of the vertical type was limited to the alar base. Insertion of the depressor septi nasi muscle was also more extensive in horizontally oriented nostrils. In terms of the shape of the lower lateral cartilage, the horizontal nostril type had a predominantly concave configuration of the lateral crus, whereas the vertical nostril type had the opposite concave configuration. A significant difference was also noted in the footplate segment ratio of the medial crus. However, no differences were observed in terms of the shape of the medial crus and the characteristics of the tip supporting structures. CONCLUSIONS: Nostril shape is mainly affected by the volume of the dilator naris anterior and posterior muscle, the insertions of the dilator naris posterior and the depressor septi nasi muscle, the shape of the lateral crus, and the footplate segment ratio.

Adult↗
PubMed2006

Augmentation rhinoplasty using injectable tissue-engineered soft tissue: a pilot study.

In a previous animal study, the authors reported that cultured human fibroblasts suspended in Restylane, which is a modified hyaluronic acid, can produce human dermal matrices with extended in vivo stability. This study was undertaken to evaluate the clinical efficacy of this method, particularly for augmentation rhinoplasty cases. Between January 2002 and June 2003, 11 patients were treated with subcutaneous implants of Restylane mixed with autologous fibroblasts for augmentation rhinoplasty. Of these 11 patients, a long-term follow-up for more than 1 year was possible in 6 patients. Appearance of reconstructed noses, degree and time of resorption, occurrence of complications, and patients' satisfaction were investigated. The injected implants remained in situ without evidence of significant resorption or loss of correction. All patients were satisfied with the achieved long-term results, and no complication occurred. The results obtained indicate that this method is well tolerated and may have a potential to be an effective means of performing augmentation rhinoplasty.

Adult↗
PubMed2005

The fate of microanastomosed digital arteries after successful replantation.

BACKGROUND: Some replanted fingers show occlusion of the anastomosed arteries, although they are successfully replanted and ultimately survive. They seem to be perfused by the soft-tissue vasculature and not by the anastomosed arteries. Therefore, this study was designed to investigate the fate of microanastomosed digital arteries after successful replantation. METHODS: The authors performed a prospective study of 75 fingers of 62 cooperative patients who had undergone successful replantation from June of 2000 to December of 2001 at Korea University Guro Hospital. We used Dopplex to screen anastomosed artery patency; thereafter, angiographic studies were also performed to confirm the Dopplex results in 18 patients. The patency of vascular pedicles was analyzed according to several parameters, namely, the cause, type, and level of injury; the number of repaired veins; and the use of an interpositional vein graft for arterial repair. RESULTS: The pulsation was not heard by Dopplex in 37 percent of anastomosed arteries after an average of 15 postoperative days. Angiographic results coincided with Dopplex results in all cases. Guillotine injuries had a pedicle occlusion rate of 8 percent, whereas crush injuries had a pedicle occlusion rate of 43 percent (p < 0.05). Regarding the level of injury, a statistically significant difference was only found between groups with a distal phalanx level of injury and those with a proximal phalanx level of injury (p < 0.05). Other parameters showed no significant differences in patency. CONCLUSIONS: We conclude that 37 percent of microanastomosed digital arteries of replanted fingers are occluded after replantation. Distinctively, amputation at the distal phalanx by crush injury increases the possibility of occlusion of microanastomosed digital arteries.

Adult↗
PubMed2005

The effect of releasing tip-supporting structures in short-nose correction.

Correction of a short nose has been regarded as one of the most challenging and at times vexing procedures in rhinoplasty. One surgical option used to prolong nasal length is the freeing of the alar cartilages from adjacent structures by dividing the nasal tip supporting tissues. Five fibrous connections are known to be important in maintaining the nasal tip shape: fibrous tissues between the upper lateral and lower lateral cartilages; the lateral border of the lower lateral cartilages at the pyriform aperture; the interdormal ligament and anterior septal angle; the footplate of the medial crus and septal cartilage; and the dermocartilaginous ligament. This study was designed to determine which of the fibrous connections providing nasal tip support offer the most effect of lengthening when these structures are divided. We performed 10 open rhinoplasties on fresh cadavers, and we sequentially divided the previously mentioned tip-supporting structures, except the dermocartilaginous ligament. The mucoperichondrium of the upper lateral and septal cartilages was also elevated, in accordance with the usual order of being released in a short-nose correction procedure. We measured the distance between the anterior septal angle and tip-defining points by using calipers while the middle crura of the lower lateral cartilages were stretched with a skin hook. We found that the most effective length was gained by severing the lateral crus from the upper lateral cartilages, and moderate gain was noted from the release at the pyriform aperture and mucoperichondrium of the upper lateral cartilage. Release of other tip-defining structures was not statistically effective.

Aged↗
PubMed2005

Potential of human bone marrow stromal cells to accelerate wound healing in vitro.

The purpose of this pilot study was to compare proliferation, collagen synthesis, and growth factor production, which are important contributing factors for wound healing, of the bone marrow stromal cells (BSCs) with those of dermal fibroblasts in vitro. Cultured human BSCs and dermal fibroblasts from the same patients were seeded in 96-well culture plates. At 1, 3, and 5 days postincubating, cell proliferation, collagen synthesis, and secretion of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), and transforming growth factor beta (TFG-beta) were compared. We did not observe great differences in cell proliferation and TFG-beta secretion. In contrast, the amount of collagen synthesis and the levels of the bFGF and the VEGF were much higher in the BSC group than the fibroblast group at each time interval (P < 0.05). Our results suggest that the BSCs may have superior potential to accelerate wound healing than the fibroblasts.

Adult↗
PubMed2004

Anatomy of the external nasal nerve.

After rhinoplasty, many patients report numbness of the nasal tip. This is primarily because of injury to the external nasal nerve. It is imperative that surgeons performing rhinoplasty be familiar with the anatomy and the common variations of this nerve. Therefore, the purpose of this study was to present an anatomical study of the external nasal nerve. Twenty external nasal nerves were examined by dissecting 10 fresh cadaver noses within 48 hours of death. On dissection, the exit of the nerve between the nasal bone and upper lateral cartilage was identified. The distance from the point of exit to the midline of the nose and the size of the nerve were measured. The course and the running plane of the nerve were investigated. The nerve branchings were also classified into three types: type I, only one nerve without any branch; type II, one nerve proximally and then splitting into two main branches at the intercartilaginous junction; and type III, two main branches from the point of exit. The point of exit of the external nasal nerve from the distal nasal bone was located 6.5 to 8.5 mm (7.3 +/- 0.6 mm) lateral to the nasal midline. The average diameter of the nerve at the point of exit was 0.35 +/- 0.036 mm. Most of the nerves (95 percent) passed through the deep fatty layer directly under the nasal superficial musculoaponeurotic layer, all the way down to the alar cartilages. In terms of the branching type, type I was observed in 10 of 20 nerves (50 percent), type II was observed in six of 20 (30 percent), and type III was seen in four of 20 (20 percent). On the basis of the results of this study, the following precautions are suggested during a rhinoplasty to minimize the chance of injury to this nerve. First, it is best to avoid deep intercartilaginous or intracartilaginous incisions so that the deep fatty layer is not invaded and the dissection is maintained directly on the surface of the cartilage (deep to the nasal superficial musculoaponeurotic layer). Second, dissection at the junction of the nasal bone and upper lateral cartilage area of one side should be limited to within 6.5 mm from the midline. Lastly, when the nasal dorsum is augmented by an onlay graft, implants or grafts less than 13 mm wide at the rhinion level should be used.

Aged↗
PubMed2004

Clinical application of fresh fibroblast allografts for the treatment of diabetic foot ulcers: a pilot study.

Diabetic foot ulcers often pose a difficult problem for health care professionals because of the defects associated with fibroblast functioning. Although there has been much interest recently in the use of topical growth factors for the treatment of diabetic foot ulcers, the effects are generally not very dramatic. Cryopreserved fibroblast implants, which are able to adjust to a wound's environment and provide the desired growth factors and other substances that may be lacking in a chronic wound, represent an exciting development and a major advance. These products may well provide growth factors in the right concentration and in the right sequence, something that has proved difficult to achieve with the topical application of recombinant growth factors. However, cell activities are impaired by cryopreservation. The purpose of this study was to assess the effects of fresh human allogeneic fibroblast grafting for the treatment of diabetic foot ulcers. Eight patients with diabetic foot ulcers ranging from 6 to 17 weeks in duration were treated. The size of the wounds ranged from 2.0 to 6.0 cm2, with three patients exhibiting exposed bones. A history of diabetic foot ulcers was present in five patients. Human dermal fibroblasts from healthy teenagers were cultured in Dulbecco's modified Eagle medium/Ham's F-12 supplemented with 10% autologous serum. The cultured cells were applied over the wounds immediately after debridement; fibrin was used as a cell carrier. A dressing was then applied with Tegaderm and kept moist until healing was complete. The progress and time for complete wound closure and patient satisfaction were assessed, with follow-up time ranging from 6 to 18 months. Complete wound healing occurred in all patients. Eleven to 21 days were needed for complete reepithelization of the wound, and no clinical or laboratory abnormalities were noted. Patient satisfaction was also very positive. In this study, the use of fresh human fibroblast allografts was found to be a safe and effective treatment for diabetic foot ulcers.

Cicatrix↗
PubMed2004

An anatomic study of nasal tip supporting structures.

Successful rhinoplasty depends on nasal tip support and its influence on nasal tip projection. It is generally agreed that the components of nasal tip support include the attachment between the upper and lower lateral cartilages, the attachment between the lateral crus of the lower lateral cartilage and the pyriform aperture, the attachment between the paired domes of the lower lateral cartilages, and the medial crural attachment to the caudal septum. However, these structures are still not clearly determined, and there was no anatomic study of nasal tip supporting structures in Asia. The purpose of this study was to determine the nasal tip supporting structures and find out the differences in these structures between white and Asian people. Ten noses of fresh cadavers were investigated. Dissection was performed and the previously mentioned nasal tip supporting structures were observed and excised. Histologic examination was done with hematoxylin and eosin stain and Van Gieson elastin stain. Macroscopic study showed that there were dense fibrous tissue between the upper and lower lateral cartilages, dense fibrous tissue and sesamoid cartilages between the lateral crus and the pyriform aperture, loose connective tissue between the paired domes of lower lateral cartilages, and no identified specific tissue between the medial crus and the caudal septum. Microscopic investigation allowed a more detailed analysis of these structures. Between the upper and lower lateral cartilages, dense collagen fibers were running in one direction and anchoring firmly to each cartilage, which meets the histologic criteria of a ligament. Between the lateral crus and the pyriform aperture, there were intermingled collagen fibers and muscular fibers, which meets the histologic criteria of fibromuscular tissue. Between the paired domes of lower lateral cartilages, there were few fibers with abundant amorphous ground substances, which meets the histologic criteria of loose connective tissue. Based on our results, we recommend that the previously mentioned nasal tip supporting structures should be named intercartilaginous ligament, sesamoid fibromuscular tissue, and interdomal loose connective tissue, respectively. In addition, we consider that the loose connection between the domes of middle crura and the absence of an attachment of the medial crura to the caudal septum can be one of the reasons why the nasal tip of Asian people is broad and unprojected and the base is wide.

Aged↗
PubMed2004

Advantages of adding a footplate incision in Asian rhinoplasty.

The dimension, shape, and projection of the nasal tip are significantly determined by the position of the footplates of the medial crura. The length of the footplate segment in Asians is much longer than that in Caucasians. A surgeon may be able to use a longer footplate segment when operating on an Asian to recreate the lower vault of the nose more effectively. The purpose of this study is to introduce the advantages of addition of a footplate incision to obtain greater satisfaction in esthetic rhinoplasty for Asians. This incision is extended along the caudal border of the footplate of the medial crura onto the floor of the nasal vestibule bilaterally, in endonasal or open approach rhinoplasty. By approximating the lateral curves of the medial crural footplates, the width and the length of the columella could be narrowed and lengthened. The columella can also be advanced caudally and thus elongate the shape of the nostrils. In addition, a cartilage graft or an implant insertion for alar base augmentation could be performed through this footplate incision, eliminating the need for an additional incision. Another advantage is that, during the correction of caudal septal deviation, displaced septal cartilage can be repositioned by suturing to the periosteum or soft tissue around the anterior nasal spine without drilling into it through an intraoral incision. One hundred ten consecutive patients who underwent esthetic rhinoplasty using our footplate incision technique between August of 1999 and May of 2002 were included in this study. A total of 66 patients had an adequate follow-up time of over 6 months. Patient satisfaction and postoperative complications were recorded. The majority of the patients (57/66 cases) were satisfied with the results of the procedure. The authors believe that the addition of the footplate incision in esthetic rhinoplasty is safe and reliable for effecting better results for Asians.

Adolescent↗
PubMed2003

Advantages of the presence of living dermal fibroblasts within restylane for soft tissue augmentation.

For the elimination of facial wrinkles and skin contour defects, injectable filler substances composed of commercially prepared nonanimal stabilized hyaluronic acid (Restylane) are now widely used. Although this method of suspension has been shown to be relatively safe and convenient, varying degrees of resorption have required repeated percutaneous injections. This study was undertaken to evaluate the feasibility of Restylane, which is a modified hyaluronic acid, combined with cultured human dermal fibroblasts, to enhance the longevity of injected implants. The histologic changes of the injected implants were also evaluated. For the test group, fibroblasts from the dermis of healthy adults were isolated and cultivated. The cultured fibroblasts were measured with a hemocytometer. Five x 105 fibroblasts suspended in 200 microl of Dulbecco phosphate-buffered saline (DPBS) were then dispersed in 200 microl of Restylane to form a 400-microl human fibroblast-Restylane mix. For the control group, 200 microl of DPBS without fibroblasts were mixed with 200 microl of Restylane. These implants were subcutaneously injected into the back of an athymic nude mouse at 6 sites, the 3 left sites composing the control group and the 3 right sites composing the test group. Twelve nude mice were injected for a total of 36 injections per group. The nodular swellings that resulted from the injections were excised to include skin beyond the swelling points down to the panniculus carnosus layer using 5-mm punches, and the weights were measured at 1, 2, 4, 8, 12, and 16 weeks after the injections. Histologic comparisons were also performed to confirm the presence of human collagen in the fibroblast-mixed Restylane group using immunohistochemical study with antihuman collagen type I polyclonal antibody. The mean weight of the control group nodules decreased throughout the examination period. The mean weight at the 16th week was 60% of the weight at the first week. On the other hand, the mean weight of the test-group nodules decreased only over the first 2 weeks. Beyond 2 weeks, there was no further significant weight change. The mean weight at the 16th week was 91% of the weight measured at the first week. Histologic examinations of the control group exhibited negative immunohistochemical staining for human collagen at each examination period. The test group exhibited positive staining after 2 weeks, indicating the presence of human collagen. These results indicate that Restylane mixed with cultured human dermal fibroblasts may be successfully injected as living grafts for long-term retention of implants.

Animals↗
PubMed2002

The timing of neovascularization in fingertip replantation by external bleeding.

To overcome venous congestion in fingertip replantation with no venous anastomosis, the authors have used a salvage procedure that consists of continuous external bleeding through a stab incision on the paraungual area and dripping a heparinized saline solution at the incision site to maintain external bleeding. Because this method requires continuous bleeding for a certain period of time, it may be a great burden on the patient; therefore, it is most important to minimize the duration of bleeding. Many authors have studied the timing of the new venous channel formation of the flap. However, to our knowledge, a study on fingertip replantations has not yet been performed. From June of 1985 to November of 1999, the authors performed fingertip replantations on 144 fingers of 137 patients using our salvage procedure at Korea University Guro Hospital. Among the 144 fingers, 101 fingers of 96 patients were successfully transplanted, including those with partial necrosis. The authors reviewed the medical records of these 101 fingers retrospectively; they compared and analyzed the necessary duration of external bleeding according to sex, age, level of injury, cause of amputation, and the type of injury. The average period of the salvage procedure was 7.6 days. Regarding age, the shortest period (5.5 days) was required for patients younger than 10 years. On the basis of the types of injuries, the duration of bleeding was shortest for the guillotine injury group (5.9 days) compared with crush (8.2 days) or avulsion (8.0 days) injuries. Sex and level of injury did not make much difference in the duration of the procedure.

Adolescent↗
PubMed2002

Anthropometric study of alar cartilage in Asians.

Measurements of 52 alar cartilages in 26 Koreans were obtained for an anthropometric study during primary open-approach rhinoplasties. The lateral crura were found most commonly to be concave, exhibited in 40% of the male patients and in 50% of the female patients. The medial crura were most often straight, found in 56% of the male patients and in 46% of the female patients. The average length, width, and thickness of the lateral crura were 19.7 mm, 10.5 mm, and 0.55 mm, respectively, in men; and 16.8 mm, 9.8 mm, and 0.54 mm, respectively, in women. The lengths of the columellar and footplate segments of the medial crura were 10.0 mm and 7.8 mm in men, and were 8.0 mm and 6.3 mm in women. These data suggest that the alar cartilage in Asians, contrary to popular myth, is not markedly smaller than that of whites. However, differences were found in the configuration of the cartilage and the length of the footplate of the medial crus.

Adult↗
PubMed2002

Low-dose propofol infusion for sedation during local anesthesia.

The safety and efficacy of lose-dose propofol for sedation were investigated on 90 consenting patients who had undergone surgical procedures with local anesthesia. After being premedicated with intravenous midazolam 0.05 mg.kg(-1), all patients were randomly divided into two groups and received intravenously either a loading dose of propofol 0.8 mg.kg(-1) followed by a continuous infusion of propofol 30 microg.kg(-1)min(-1) (propofol group) or an equivalent volume of saline (placebo group) during operation. Study groups were compared with respect to the level of sedation, hemodynamic variables, oxygen saturation, and the incidence of intraoperative side effects. In addition, the discharge time and the satisfaction of both patients and surgeons with this sedative technique were assessed. Propofol reduced patients' discomfort and lowered their arterial pressure and heart rate during the infiltration of local anesthetics. It also promoted an adequate level of sedation without clinically significant oxygen desaturation in the intraoperative period. Surgeons and patients in the propofol group showed a higher level of satisfaction than those in the placebo group. There was no significant difference between the two groups with regard to the incidence of adverse effects and the discharge time. In conclusion, it was found that the use of low-dose propofol infusion was a safe and effective sedative technique for local anesthesia.

Adult↗
PubMed2002

Extended incision in open-approach rhinoplasty for asians.

The purpose of this study was to introduce an extended incision in open-approach rhinoplasty for obtaining greater satisfaction in aesthetic rhinoplasty for Asians. This incision is the same as for the usual open rhinoplasty incision, but it is extended along the caudal border of the footplates of the medial crura onto the floor of the nasal vestibule to access the footplates of the medial crura more easily. This simple extended incision enabled the authors to achieve further tip projection because the pressure of the skin flap on the tip was reduced. By approximating the lateral curves of the medial crural footplates, the width and the length of the columella were narrowed and lengthened, respectively. The columella was also advanced caudally; thus, the shape of the nostrils could also be elongated. In addition, a cartilage graft or an implant insertion for alar base augmentation could be performed through this extended incision without an additional incision. Another advantage was that in correction of caudal septal deviation, displaced septal cartilage could be repositioned by suturing to the periosteum or soft tissue around the anterior nasal spine without drilling into it through an intraoral incision. Fifty-one consecutive patients who underwent this extended open-approach rhinoplasty between August of 1999 and September of 2000 were included in this study. A total of 40 patients had an adequate follow-up time of over 6 months. Patient satisfaction and postoperative complications were recorded. The majority of the patients (35 of 40) were satisfied with the results of the procedure. Two patients had complications of nostril-scar contracture requiring close follow-up. There were no cases of implant extrusion, displacement, or infection. No patients experienced transcolumellar or extended-incision scarring. Although further studies and longer follow-up are needed to determine the value of this incision, the authors believe that the addition of the extended incision in open-approach rhinoplasty is safe and reliable for effecting better results for Asians.

Cicatrix↗