1.A FEM analysis for initial stress on the upper canine by orthodontic force of intrusion arch wire activation.
Jeong Weon KANG ; Kyung Suk CHA ; Jin Woo LEE
Korean Journal of Orthodontics 1998;28(3):391-398
The purpose of this study was to find the distribution and measurement of compressive and tensile stress when intrusi- on arch wire is forced engage with upper canine and to analysis stress at each section through FEM. And we compare compressive and tensile ratio at each section. The results were as follows. 1. At FA point and cemento-enamel junction of upper canine, compressive and tensile force ratio is about the same. 2. At apex, compressive force is the four times as tensile force. ; In intrusion, we show root resorption at apex. 3. At Cemento-enamel junction, the compressive and tensile force show the maximun value except FA point.
Root Resorption
2.Reconstruction of the soft tissue deffect of lower extremity in complicated case.
Jeong Soo LEE ; Taek Keun KWON ; Dong Jin LEE ; Jin Han CHA ; Yang Woo KIM
Journal of the Korean Society of Plastic and Reconstructive Surgeons 1998;25(4):686-696
This study includes 19 cases of complicated low extremity injury to whom underwent microvascular free-tissue transfer in cases of open comminuted fracture, osteomyelitis, and vascular compromise or extensive soft tissue defect from Nov. 1994 to July 1997. The average time after injury to coverage was 25 days. The nineteen patients underwent a total of nineteen free tissue transfers primarily, and eighteen (94.7 per cent) of the transfers survived. Major complications were encountered recurrent failure of the free tissue transfer in one patient and partial necrosis in the other flap, which were successfully treated by flow-through radial forearm free flap and distally based superficial sural artery flap respectively. Two patients were sustained below knee amputation, one above knee amputation, despite of survival of flaps. This reveals limb salvage in 84 percent. The microvascular reconstruction is a versatile and reliable methods in complicated cases after severe trauma. Free tissue transplantation should be considered as a primary treatment in such complicated cases.
Amputation
;
Arteries
;
Extremities
;
Forearm
;
Fractures, Comminuted
;
Free Tissue Flaps
;
Humans
;
Knee
;
Limb Salvage
;
Lower Extremity*
;
Necrosis
;
Osteomyelitis
;
Tissue Transplantation
;
Transplants
3.The Effect of Ginkgo Biloba Extract(EGb 761)on the Patency Rate after Microvascular Anastomosis on Severely Damaged Microvasculature in the Rats.
So Ra KANG ; Dong Jin LEE ; Jin Han CHA ; Yang Woo KIM
Journal of the Korean Society of Plastic and Reconstructive Surgeons 1999;26(3):448-452
Replantation after crush amputation has a relatively low success rate. Thrombus formation due to vessel and tissue trauma is considered as the principal cause of failure. In the laboratory and clinically, we have been tried to improve the post-anastomosis patency rate in crushed microvasculature. To accomplish this, we have usually used several anticoagulant drugs. Extracts from the leaves of Ginkgo biloba (EGb) have been used therapeutically for centuries. EGb exerts a number of pharmacologic actions. Eighty rats were control group and another 80 rats were treated with EGb 761. The femoral arteries underwent crush injury with an energy of 0.4J, and the vessles in each group were divided and anastomosed by a standard microsurgical technique. Each group was comprised as follows: (1) control group(A1,A2): group A1(n=40); intraluminal saline irrigation, group A2(n=40); intraluminal saline irrigation+heparin 40 u/ml(IV). (2) EGb 761 treated group(B1, B2): groupB1(n=40); intraluminal saline irrigation, group B2(n=40); intraluminal saline irrigation + heparin 40 u/ml(IV). At postoperative 14 days, the patency rates were; group A1 20%, group A2 77.5%, group B1 47.5%, group B2 92.5%. These results were interpreted as follows: the patency rate was significantly increased in the EGb 761-only treated group(p>0.01), the heparin-only treated group(p>0.01), and the EGb 761 and heparin-combined at crushed microvessel surgery. However the patency rate of the EGb-only treated group was significantly lower than that of the heparin-only treated group(p>0.01). And in the EGb 761 and heparin-combined treated group compared to the heparin-only treated group, there was some patency rate increase in the combined treated group, but there was no significant difference between them(p=0.060).
Amputation
;
Animals
;
Anticoagulants
;
Femoral Artery
;
Ginkgo biloba*
;
Heparin
;
Microvessels*
;
Pharmacologic Actions
;
Rats*
;
Replantation
;
Thrombosis
4.Management of Fournier's Gangrene with PGE1 and Bilateral Superomedial Thigh Flap.
Hye June PARK ; Dong Jin LEE ; Jin Han CHA ; Yang Woo KIM
Journal of the Korean Society of Plastic and Reconstructive Surgeons 1999;26(5):1077-1081
Fournier's gangrene is an infective necrotizing fasciitis of the perineal, genital or perianal regions. Management of this disease has involved prompt surgical debridement with initiation of broad spectrum antibiotics and intensive supportive care. Multiple debridements orchiectomy, urinary deversion, and fecal diversion should be performed as clinically indicated. Hyperbaric oxygen therapy and topical application of unprocessed honey may prove to be useful adjuncts as new therapies. After excision of all necrotic tissue, the tissue losses have been managed by primary repair. split-thickness skin grafts, rotational or free myocutaneous flaps and omental flaps. Skin graft did not take on bare testis lacking the tunica vaginalis, and gracilis myocutanous flap was too bulky to cover the scrotal area. The progress of necrosis ceased by using intravenous PGE1 injection in the aspect of characteristic obliterative endarteritis causing cutaneous and subcutaneous vascular thrombosis and necrosis of tissue in Fournier's gangrene. We have reconstructed large scrotal defects with bilateral superomedial thigh flap in three Fournier's gangrene patients after stopping tissue necrosis with PEG1 treatment and several surgical debridements of the wounds. The use of this flap ensures a virtually normal sensation, which is important for the erotic propensity of the scrotum. Easy flap design and dissection, as well as primary closure of the donor site, are another benefits of this method.
Alprostadil*
;
Anti-Bacterial Agents
;
Debridement
;
Endarteritis
;
Fasciitis, Necrotizing
;
Fournier Gangrene*
;
Honey
;
Humans
;
Hyperbaric Oxygenation
;
Myocutaneous Flap
;
Necrosis
;
Orchiectomy
;
Scrotum
;
Sensation
;
Skin
;
Testis
;
Thigh*
;
Thrombosis
;
Tissue Donors
;
Transplants
;
Wounds and Injuries
5.Nerve Regeneration After Autogenous Nerve Graft Using Perfabricated Adiponeural and Myoneural Flap: An Experimental Study.
Hong Kyu CHO ; Dong Jin LEE ; Jin Han CHA ; Yang Woo KIM ; Ki Duk PARK
Journal of the Korean Society of Plastic and Reconstructive Surgeons 2000;27(1):65-71
Most of the peripheral nerve injuries from crushing or compressive forces are accompanied by surrounding soft tissue injuries. As a result, poor vascularity due to fibrosis and sacr formation compromises regeneration of the grafted nerve. Vascularized nerve graft shows superior regeneration to that of a non-vascularized one. However, the human body provides few donor sites of vascularized nerve graft clinically. We presumed that the prefabricated myoneural or adiponeural flap, which include fabricated nerves wrapped with surrounding vascularized muscle or adipose tissue flap, influences superiorly on the regeneration of grafted nerve because that surrounding vasculatity indirectly enhances the vascularity of the grafted nerve itself. Thirty adult male Sprague-Dawley rats were divided into three groups: 1) conventional reversed autogenous graft of the femoral nerve alone(n=10); 2) nerve graft entubulated with abdominal adipose tissue flap with a pedicle of inferior epigastric artery(n=10); 3) nerve graft entubulated with adductor muscle flap with a pedicle of the first muscular branch of the femoral artery(n=10). At three months postoperatively, grafted nerves were examined by electrophysiologic study to check amplitudes and motor nerve conduction velocities, as well as histopathologic study for evaluation of regenerated nerve cells, fibrosis and neo-vascularization. Consquently, nerve regeneration was found in all three groups. Both the myoneural and adiponeural flap groups had better improved results of nerve regeneration compared to that of the conventional nerve graft group. The result of myoneural flap group was superior to that of the adiponeural flap group. The myoneural flap group showed minimal fibrosis and less prominent neovascularization around moderately regenerated nerves. The adiponeural flap group showed more severe perineural and endoneural fibrosis, as well as vascular proliferation around focal regenerated nerves. The results of myoneural flap group proved to be statistically significant. We concluded that it is possible to use nerve graft entubulated with a vascularized muscle flap (myoneural flap) as a substitute for vascularized nerve graft.
Abdominal Fat
;
Adipose Tissue
;
Adult
;
Femoral Nerve
;
Fibrosis
;
Human Body
;
Humans
;
Male
;
Nerve Regeneration*
;
Neural Conduction
;
Neurons
;
Peripheral Nerve Injuries
;
Rats, Sprague-Dawley
;
Regeneration
;
Soft Tissue Injuries
;
Tissue Donors
;
Transplants*
6.An experimental study on the effect of Ginkgo Biloba extract (EGb 761) on the healing process after weak crush injury.
So Ra KANG ; Dong Jin LEE ; Jin Han CHA ; Yang Woo KIM
Journal of the Korean Society of Plastic and Reconstructive Surgeons 2000;27(1):60-64
Late results of microvascular patency after crush or crush avulsion injury have been relatively poor. A key factor in the poor results may relate to the presence of damaged tissue, but the mechanism of this thrombus formation is still imcompletely understood. One current theory about the origin of thrombus after vessel trauma involves increased exposure of the subendothelial tissue to platelets that adhere and aggregate at the injury site, initiating thrombus formation. Most surgeons have usually used several anticoagulant drugs to prevent thrombosis for 2-3 weeks after trauma or microvascular repair. We thought that Ginkgo biloba extract (EGb 761), which has a number of pharmacologic actions, could promote microvasculature healing and prevent thrombosis. The femoral arteries of rats were dissected. Each group was as follows:-1. group A (n=10): intact group (not crushed vessel),2. group B (n=10); crushing injury (not EGb 761-treated group),3. group C (n=10); crushing injury (EGb 761-treated group). Group B and C underwent crush injury with the energy of 0.07J. We compared patency rate and histological examination. All arteries were patent at postoperative 14 days, and in histologic finding, group C (group with EGb 761 treatment among the crushed injury group) showed significant improvement of vascular endothelial and medial regeneration.
Animals
;
Anticoagulants
;
Arteries
;
Femoral Artery
;
Ginkgo biloba*
;
Microvessels
;
Pharmacologic Actions
;
Rats
;
Regeneration
;
Thrombosis
7.The Reliability of Ultrasonographic Fending of Silicone Breast Implant Rupture.
Won June YOON ; Dong Jin LEE ; Jin Han CHA ; Yang Woo KIM
Journal of the Korean Society of Aesthetic Plastic Surgery 1998;4(1):52-59
This retrospective study evaluated possible rupture of silicone gel breast implants in 92 patients. the series included patients undergone augmentation mammoplasty(n=59), and reconstructive mammoplasty(n=23) from Sep. 1993 to Aug. 1996. the age of implants ranged from 4 months to 8 years(mean:23.1months). of these, 19 cases displayed Ultrasonographic sings of rupture. of 13 implants removed, 7 were intact and 6 were ruptured. Implant contour deformities and radial folds are often seen in both ruptured and intact silicone implants and therefore cannot serve as reliable signs of rupture. A stepladder sign in intact implant is believed to be the result of reverberation artifacts within the interior of the implant. Due to these false-positive ultrasonographic findings, ultrasonographiy is not as absolutely reliable tool for the diagnosis of implant rupture. Alternative imaging methods(CT, MRI) are required to establish an accurate preoperative diagnosis.
Artifacts
;
Breast Implants*
;
Breast*
;
Congenital Abnormalities
;
Diagnosis
;
Humans
;
Retrospective Studies
;
Rupture*
;
Silicone Gels*
8.CT Finding of Ruptured Splenic Artery Aneurysm after Cesarean Section: A Case Report.
Journal of the Korean Radiological Society 2000;42(3):513-515
Spontaneous rupture of a splenic artery aneurysm during puerperium is rare and is due to the non-specific clinical apperance, diagnosis is difficult. We describe a case of spontaneous rupture of splenic artery aneurysm after a Cesarean section. CT showed high-density ascites localized in the lesser sac and left retroperitoneum.
Aneurysm*
;
Arteries
;
Ascites
;
Cesarean Section*
;
Diagnosis
;
Female
;
Hemorrhage
;
Peritoneal Cavity
;
Peritoneum
;
Postpartum Period
;
Pregnancy
;
Rupture, Spontaneous
;
Splenic Artery*
9.Gastric-cancer-related Inquiries and Questionnaires through an Internet Homepage.
Dae Ho AHN ; Dong Woo SHIN ; Jae Ho CHEONG ; Woo Jin HYUNG ; Seung Ho CHOI ; Sung Hoon NOH
Journal of the Korean Gastric Cancer Association 2004;4(4):219-224
PUPOSE: Through a survey on an Internet homepage, we conducted research concerning the need of patients and their families for information on gastric cancer. We also assessed their interest in gastric cancer. MATERIALS AND METHODS: We analyzed 619 inquiries presented from June 2002 to September 2003 and 524 replies submitted to a questionnaire survey delivered by the Internet homepage (www.gastriccancer.co.kr) from August to October 2003 to gastric cancer patients and their families. RESULTS: Analysis of Inquiries: The classified inquiries listed in order of frequency are as follows: treatment, prognosis, stages, symptoms, pathophysiology, diagnostic modalities, favorable food, etiology, follow-up, etc. Among the inquiries about treatment, the most frequent subgroup was about the scope of surgery or perioperative implications. Next came questions concerning chemotherapy. Among the questions from patients yet to be operated, on those about operability and the prognosis were most frequent. Among the patients who had undergone a resection, questions on complications and the corresponding prognosis were most frequent. The concern from patients with inoperable or recurrent cancers was related to terminal care and/or chemotherapy. Analysis of Questionnaires: The respondents acquired information on gastric cancer from the Internet (40%), doctors (32%), the mass media (15%) and acquaintances (13%). Only 6% of the respondents were sufficiently satisfied with the information provided by doctors. Among the respondents, 89.9% were interested in complementing treatment with folk remedies while only 5% were not. CONCLUSION: Patients and their families were eager to get information about gastric cancer. However, many of them found the doctors' information to be insufficient. Our suggestion is that the public health, academic societies, medical institutions, and public organizations should endeavor to provide through an activated Internet network correct information on gastric cancer.
Complement System Proteins
;
Surveys and Questionnaires
;
Drug Therapy
;
Follow-Up Studies
;
Friends
;
Humans
;
Internet*
;
Mass Media
;
Medicine, Traditional
;
Prognosis
;
Public Health
;
Surveys and Questionnaires*
;
Societies, Medical
;
Stomach Neoplasms
;
Terminal Care
10.Clinical Effects of Conjunctiva-Muller Muscle Resection in Anophthalmic Ptosis.
Sung Woo HA ; Jong Mi LEE ; Woo Jin JEUNG ; Hee Bae AHN
Korean Journal of Ophthalmology 2007;21(2):65-69
PURPOSE: To evaluate the clinical effects of conjunctiva-Muller muscle resection through conjunctival incision in anophthalmic patients with mild ptosis. METHODS: Conjunctiva-Muller muscle resection was performed by one surgeon in 8 patients (8 eyes) who had received evisceration or enucleation and responded to 10% phenylephrine solution to correct ptosis. The average age of the patients was 35.87+/-13.4 years. Ptosis was seen from 1 to 34 months after evisceration or enucleation. The preoperative MRD 1 was -2 to 0.5 mm (average: -0.25+/-1.10 mm) and the difference of MRD 1 between before and after 10% phenylephrine use was 2.56+/-0.98 mm. The Muller muscle was resected 7.5 to 9 mm through conjunctival incision during surgery to match the MRD 1 of sound eye. Mean follow-up period after the operation was 2 to 16 months (average: 8.1 months). RESULTS: Postoperatively, the MRD 1 increased by 1.81+/-0.88 mm on the average, corresponding to the improvement in lid elevation after the use of 10% phenylephrine performed before resection. Surgery was successful in most patients, and postoperative difference in MRD 1 was less than 1 mm from the sound eye. No special postoperative complication was observed. CONCLUSIONS: Conjunctiva-Muller muscle resection is one of the effective methods of correcting mild ptosis in anophthalmic patients.
Adult
;
Anophthalmos/*complications
;
Blepharoptosis/etiology/*surgery
;
Conjunctiva/*surgery
;
Eyelids/physiopathology
;
Facial Muscles/*surgery
;
Female
;
Follow-Up Studies
;
Humans
;
Male
;
Middle Aged
;
Muscle Contraction
;
Ophthalmologic Surgical Procedures/*methods
;
Time Factors
;
Treatment Outcome