• The Korean Journal of Nuclear Medicine
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• v.33 no.2
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• pp.163-171
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• 1999

Purpose: Liquid beta emitter filled in angioplasty balloon could be used to perform endovascular balloon brachytherapy to prevent coronary artery restenosis. We investigated the dosimetry for Re-188-DTPA liquid-filled balloon and medical internal radiation dosimetry in case of balloon leakage. Materials and Methods: We estimated radiation dose from an angioplasty balloon (20 mm length, 3 mm diameter cylinder) to the adjacent vessel wall using Monte Carlo EGS4 code. We obtained time-activity curves of kidneys in normal dog and calculated $T_{max},\;T_{1/2}$. Using MIRDOSE3 program, we estimated absorbed doses to the major organs (kidneys, bladder) and the whole body when we assumed that balloon leaked all the isotope contained. Results: The radiation dose was 17.5 Gy at the balloon surface when we applied 3,700 MBq/ml of Re-188 for 100 seconds, Fifty percent of the energy deposited within 1 mm from the balloon surface. The estimated internal dose to the whole body was 0.005 mGy/MBq and 18.5 mGy for the spillage of 3,700 MBq of Re-188. Conclusion: We suggest that Re-188-DTPA can be used for endovascular balloon brachytherapy to inhibit coronary artery restenosis after angioplasty with tolerable whole body radiation dose in case of balloon rupture.

• Polymer(Korea)
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• v.32 no.3
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• pp.284-289
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• 2008

Polymer is a critical component of local drug delivery to prevent restenosis. This study tested whether poly(n-butylmethacrylate)(PBMA) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(PHA) was candidates for this purpose. In vitro release of paclitaxel from PBMA and PHA loaded with 10% paclitaxel exhibited a triphasic release profile, with a fast initial and intermediate second phase followed by a slow release phase. Perivascular delivery of paclitaxel using these films inhibited neointimal hyperplasia in balloon-injured rat carotid arteries. The paclitaxel-loaded PBMA or PHA groups showed significant neointimal formation reductions versus the control groups (PBMA vs control: $0.03{\pm}0.02$ vs $0.10{\pm}0.01\;mm^2$, p<0.05; PHA vs control: $0.04{\pm}0.03$ vs $0.09{\pm}0.01\;mm^2$, p<0.05). This study suggests that PBMA and PHA could be good candidate polymers of local drug delivery to prevent restenosis. Perivascular delivery using these films represents a possible approach for prevention of restenosis. These can be candidate polymers for drug eluting stents.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.223-224
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• 2006

• Proceedings of the Korean Nuclear Society Conference
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• 1998.10a
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• pp.345-345
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• 1998

• Journal of Chest Surgery
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• v.25 no.7
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• pp.732-735
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• 1992

We experienced a case of application of Gianturco Self-Expendable Metal vascular stent for S V.C. syndrome at the postoperative stae of pneumonectomy for Lung cancer[Squamous cell carcinoma, stage IIIa] Placement was performed under fluoroscopic guidance. Clinical problem for patient was resolved satisfactorily Long-term follow-up is required to determine restenosis, complication, and recurrence of cancer, etc.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.10a
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• pp.337.1-337
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• 1999

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.205.2-205.2
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• 2000

• Journal of the Korean Society for Precision Engineering
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• v.29 no.1
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• pp.103-108
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• 2012

Restenosis symptom, which is well known as a problem of stents, is due to the recoil and expansion pressure depending on shapes of stent. In order to reduce the effect of recoil problem, study on pattern and shape for the stent is required and the expansion pressure and recoil should be evaluated. This paper aims at evaluating mechanical characteristics of stent used in surgery for vessel stenosis. The expansion process of coronary artery stent in vessel for two models including the Cypher$^{(R)}$ from Johnson & Johnson$^{TM}$ and a suggested model were simulated using the Finite Element Analysis. Comparison of the directional recoil simulation results was made. The issues in the deformed shape of vessel and recoil of Cypher$^{(R)}$ were partially resolved in the suggested model. Therefore, the shape design suggested in this paper was able to reduce the restenosis symptom.

• Journal of Chest Surgery
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• v.12 no.4
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• pp.361-364
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• 1979

The first Mitral Commissurotomy was performed for tight mitral stenosis on March 1957. The patient was at that time 22-year-old male, student. The longest follow 9p for 22 years and 8 months has been obtained. During the follow up period, late deterioration due to restenosis developed 4 years after initial good result and reoperation was succeeded by transventricular Mitral Valvotomy with Tubb`s ilator on April 1964. The possible cause of restenosis was attributed to recurrent rheumatic activity. After more than 13 years long-good life following 2nd operation, Endocarditis such as episode of high fever & chill intermittently followed by mild fever and night sweat, I t. tibial artery embolization and rupture of aortic cusp. At present, patient complained of no subjective symptom, enjoying ordinary life {NYHA II]. Blood pressure has been 110/50-60 mmHg, trivial diastolic murmur at apex and moderate degree of mechanical murmur on diastole at Erb`s rea. Neither signs of RVH for mitral stenosis nor sign of LVH. ST-T change for aortic regurgitation appeared yet during last 2 yrs. The patient`s are for prevention of Rheumatic activity and development of endocarditis is important for obtaining the better long-term result.

• Korean Journal of Bronchoesophagology
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• v.9 no.2
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• pp.60-64
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• 2003

Restenosis frequently develops with granulation and overgrowth of scar following surgical treatment for laryngotracheal stenosis. Various methods such as stenting or CO2 laser application have been used to prevent restenosis, but they were seldom unsatisfactory. Mitomycin is an antineoplastic antibiotics derived from Streptomyces caespitosus; it inhibits fibroblast proliferation and acts as an alkylating agent to inhibit DNA synthesis. This study was desinged to evaluate effectiveness and determine indications of usage of topical mitomycin for laryngotracheal stenosis as a nonsurgical means of reducing postoperative granulation and scar tissue formation. Patients and Method : A retrospective study was performed on eight cases of laryngotracheal stenosis with topical mitomycin application. The author analyzed clinical outcomes of operative treatment with topical mitomycin. Patients underwent laryngotracheal reconstruction, endoscopic granulation removal, or bronchoscopic bougienage followed by topical application of mitomycin (0.4 mg/$m{\ell}$, 4minuntes) on the lesion intraoperatively. Result : Overall success rate of decannulation was 38% ($\frac{3}{8}$). Successful decannulation was possible in 75% ($\frac{3}{4}$) of laryngeal stenosis patients, 75% ($\frac{3}{4}$) of children, 60% ($\frac{3}{5}$) of the patients without previous surgery, and 75% ($\frac{3}{4}$) of bronchoscopic bougienage. Conclusion : The topical application of mitomycin in laryngotracheal stenosis was effective in untreated pediatric laryngeal stenosis which underwent bronchoscopic bougienage. Our results show that the topical mitomycin application for laryngotracheal stenosis could be a effective adjuvant treatment.