1.Deduction and Verification of Optimal Factors for Stent Structure and Mechanical Reaction Using Finite Element Analysis.
Dong Min JEON ; Won Gyun JUNG ; Han Ki KIM ; Sang Ho KIM ; Il Gyun SHIN ; Hong Seok JANG ; Tae Suk SUH
Korean Journal of Medical Physics 2010;21(2):201-208
Recently, along with technology development of endoscopic equipment, a stent has been developed for the convenience of operation, shortening of recovery times, and reduction of patient's pain. To this end, optimal factors are simulated for the stent structure and mechanical reaction and verified using finite element analysis. In order to compare to present commercialized product such as Zilver (Cook, Bloomington, Indiana, USA) and S.M.A.R.T (Cordis, Bridgewater Towsnhip, New Jersey, USA), mechanical impact factors were determined through Taguchi factor analysis, and flexibility and expandability of all the products including ours were tested using finite element analysis. Also, important factors were sought that fulfill the optimal condition using central composition method of response surface analysis, and optimal design were carried out based on the important factors. From the centra composition method of Response surface analysis, it is found that importat factors for flexibility is stent thickness (T) and unit area (W) and those for expandability is stent thickness (T). In results, important factors for optimum condition are 0.17 mm for stent thickness (T) and 0.09 mm2 for unit area (W). Determined and verified by finite element analysis in out research institute, a stent was manufactured and tested with the results of better flexibility and expandability in optimal condition compared to other products. Recently, As Finite element analysis stent mechanical property assessment for research much proceed. But time and reduce expenses research rarely stent of optimum coditions. In this research, Important factor as mechanical impact factor stent Taguchi factor analysis arrangement to find flexibility with expansibility as Finite element analysis. Also, Using to Center composition method of Response surface method appropriate optimized condition searching for important factor, these considering had design optimized. Production stent time and reduce expenses was able to do the more coincide with optimum conditions. These kind of things as application plan industry of stent development period of time and reduce expenses etc. be of help to many economic development.
Academies and Institutes
;
Finite Element Analysis
;
Indiana
;
New Jersey
;
Pliability
;
Stents
2.Tibial Plateau Coverage in Total Knee Replacement Arthroplasty: Coverage on 12 quadrants.
Hyun Kee CHUNG ; Choong Hyeok CHOI ; Jong Heon KIM ; Kyoung Tae KIM ; Sun Il KIM ; Dong Pyo CHANG
The Journal of the Korean Orthopaedic Association 1999;34(6):1081-1086
PURPOSE: We investigated proximal tibial cutting surface in total knee replacement arthroplasty to improve its coverage and get basic data for developing more adequate tibial components for Koreans. MATERIALS AND METHODS: Of cases of total knee replacement arthroplasty performed by one surgeon between September 1995 and October 1996, we chose 100 cases with no bony defect on resected tibial surface. We traced the outline of tibial resection margin manually and then, decided the most adequate size for each tibial tray from 5 companies, AGC (Biomet, Warsaw, USA), Advantim (Wright medical technology, Arlington, USA), AMK (DePuy, Warsaw, USA), MGII (Zimmer, Indiana, USA), and Series 7000 (Osteonics, New Jersey, USA). We divided the tibial cutting surface with 12 quadrants by 30 degree radian. Then, we overlaped both images (traced tibial surface margin and tibial tray) on the computer and fixed the position when we got the largest coverage of area. From this position we calculated the coverage, underhang and overhang ratios by pixel counts. During this process, we discarded 20 cases because of inadequate overlapping. RESULTS: The overall average ratio of coverage was 82.3%, underhang 17.3%, and overhang 6.0%. The consequence of good coverage and minimal underhang were posterolateral, posteromedial, anterolateral, anteromedial and posterior aspects sequentially. But the posterior side was more overhanged by tibial component than anterior side. CONCLUSION: We feel that improving coverage on posterior and anteromedial portion is key to increasing the coverage ratio of proximal tibia in total knee replacement arthroplasty.
Arthroplasty*
;
Arthroplasty, Replacement, Knee*
;
Indiana
;
New Jersey
;
Tibia
3.Ureteroappendicocutaneostomy(Appendix conduit): 4 Cases.
Korean Journal of Urology 1994;35(12):1363-1368
Cutaneous urinary diversion with intestinal conduits after cystectomy in bladder cancer has been popular. However, because of loss of continence and storage capacity of the lower urinary tract, the situation of patients with an ileal conduit was far from satisfactory with respect to quality of life. Recently, continent urinary diversion has begun to achieve worldwide popularity as Kock, Mainz, or Indiana pouch techniques have been more feasible and accessible, but these techniques have been known as time consuming procedures. In high risk patients with bladder carcinoma more simple techniques of urinary diversion is needed. Herein, we report the outcome of ureteroappendicocutaneostomy (appendix conduit) with radical cystectomy performed in 4 bladder carcinoma patients in whom unilateral nephroureterectomy was necessary or previously done.
Cystectomy
;
Humans
;
Indiana
;
Quality of Life
;
Urinary Bladder
;
Urinary Bladder Neoplasms
;
Urinary Diversion
;
Urinary Tract
4.Changes of Serum Glucose according to Sensory Block Level and Intrathecal Epinephrine , Morphine during Spinal Anesthesia.
Ho Jung LEE ; Man Mo YOON ; Bong Il KIM
Korean Journal of Anesthesiology 1992;25(6):1137-1142
The purpose of this study was to observe the effect of spinal anesthesia on serum glucose which is still controversial and to observe the changes of serum glucose according to the blocked level and intrathecal morphine and epinephrine mixed with local anesthetic(tetracaine). 67 patients(age; 16-83, ASA. ps. 1-3) for lower abdominal or lower extremity operation, had no disease affecting serum glucose level and were not contraindicated for spinal anesthesia, were selected randomly and divided them into each 3 group depending on the sensory block level and with or without intrathecal morphine and epinephrine mixed with local anesthetic (tetracaine) as fo11ows; Ggroup l (N =8); high spinal anesthesia(above T4) Group 2(N=23); middle spinal anesthesia(T5~T9) Group 3(N=26); low spinal anesthesia(below T10) Group A(N=18): tetracaine only Group B(N=17); tetracaine+epinephrine(0.2 mg) Group C(N = 32); tetracaine+ epinephrine(0.2 mg)+ morphine(0.2 mg) All patients except emergency cases were premedicated with nalbuphine(5 mg) and droperidol(2.5mg) or hydroxyzine(1 mg/kg) and were kept NPO 6-12hr. Hartman's solution were used for the maintenance fluid. Serum glucose were measured before operation, just immediate before and after spinal anesthesia and at 30 min. after starting operation with Glucometer-2(Miles inc, Indiana, USA). The results were as follows; 1) The values of serum glucose after spinal anesthesia were not changed significantly compared with those of the immediate before anesthesia(P> 0.05). 2) The values of serum glucose according to sensory block level were not changed significanly compared with each group(P>0.05). 3) The values of serum glucose when using mixed epinephrine and morphine with tetracaine intrathecally were not changed significantly compared with using tetracaine only(P>0.05). These results suggested that spinal anesthesia itself did not affect serum glucose level, and neither the sensory block level nor iatrathecal epinephrine and morphine affect serum glucose level. Increased serum glucose caused by surgical stress might be attenuated by spinal anesthesis when lower extremity and lower abdominal operation.
Anesthesia, Spinal*
;
Blood Glucose*
;
Emergencies
;
Epinephrine*
;
Humans
;
Indiana
;
Lower Extremity
;
Morphine*
;
Tetracaine
5.A clinical experience of urinary diversion: postoperative complications of diversion.
Jeong Zoo LEE ; Jong Byung YOON
Korean Journal of Urology 1991;32(1):104-111
124 cases of urinary diversion were reviewed from September, 1974 to March. 1990. Studies were underwent mainly concerning the indications and the postoperative complications in several diversion procedures such as ileal conduit. ileocecal conduit, tubeless cutaneous ureterostomy. Kock pouch and Indiana pouch. Although ileal conduit and ileocecal conduit are one of reliable method with broad applications, the early and late complications are often troublesome. Also continent diversion such as Kock pouch and Indiana pouch need the long operative time with technical difficulties. Tubeless cutaneous ureterostomy have high incidence of stomal stenosis especially in normal sized ureter. Because there are no ideal urinary diversion today, the careful and thorough evaluation and consideration should be given in selecting appropriate urinary diversion method in each different cases.
Colonic Pouches
;
Constriction, Pathologic
;
Incidence
;
Indiana
;
Operative Time
;
Postoperative Complications*
;
Ureter
;
Ureterostomy
;
Urinary Diversion*
6.Indiana continent ileocecal reservoir: early followup of 10 cases.
Korean Journal of Urology 1991;32(6):1003-1010
From May 1990 to July 1991. 11 bladder tumor patients were treated with Indiana continent ileocecal reservoir after radical cystectomy with pelvic lymphadnectomy and l0 were followed up. The average operation time for making pouch was 5 hours 22 minutes. The reservoir was created with reconfiguration of disrupted cecum and ileal patch and its average maximal capacity was 527. 8cc. The average interval of catheterization was 5 hours 36 minutes and the average catheterized urine volume was 357cc. The average intrareservoiral maximal pressure was 29.4cmH2O and the average intraluminal maximal pressure of plicated terminal ileal segment along with ilececal valve was 48cmH2O. All of 10 patients(100%) had successful daytime continence and 5 were able to sleep all night without catheteritation. Tunneled ureteral implantations along the tenia of the cecum were revealed no reflux on reservoirogram. The complications were 2 cases of temporary urine leakage From stoma site. 1 wound infection and 1 stomal bleeding. From the above results, although duration of followup is short, we can anticipate a superb outcome after experience further cases with this procedure, since successful continence and antireflux are achieved at this time.
Catheterization
;
Catheters
;
Cecum
;
Cystectomy
;
Follow-Up Studies*
;
Hemorrhage
;
Humans
;
Indiana*
;
Ureter
;
Urinary Bladder Neoplasms
;
Wound Infection
7.Tibial Plateau Coverage in total knee Replacement arthroplasty.
Hyunkee CHUNG ; Choonghyeok CHOI ; Jongheon KIM ; Kyoungtae KIM ; Sunil KIM ; Kongpyo CHANG
Journal of the Korean Knee Society 1998;10(2):135-140
Maximizing tibial coverage is an important consideration in total knee replacement arthroplasty to provide stability and even load transfer and to improve long term survival rate of the implants. We evaluated the coverage, underhang and overhang ratio for the proximal tibial resection surface during total knee replacement arthroplasty in Koreans. After cutting the proximal tibia, the outline of tibial resection surface was traced manually. We compared 5 tibial tray designs, AGC(Biomet, Warsaw, U.S.A.), Advantim(Wright medical technology, Arlington, U.S.A.), AMK(DePuy, Warsaw, U.S.A), MG II(Zimmer, Indiana, U.S.A.), Series 7000(Osteonics, New Jersey, U.S.A.), which have been commercially used in Korea for total knee replacement arthroplasty. The average percentage of coverage area were 83.3% in AGC, 81.6% in AMK, 80.3% in MG II, 80.2% in Advantim and 76.9% in Series 7000. The average percentage of underhang were 16.7% in AGC, 18.4% in AMK, 19.6% in MG II, 19.8% in Advantim and 23,1% in Series 7000. The average percentage of overhang were measured 7.97% in AGC, 7.86% in AMK, 8.01% in MG II, 8.77% in Advantim and 10.14% in Series 7000. So average coverage percentage of tibial cutting surface was 80.5% in Koreans. The factors which affect the optimal coverage, were the shape, dimensional interval of tibial trays and the number of practically useful tibial trays for Koreans.
Arthroplasty*
;
Arthroplasty, Replacement, Knee*
;
Indiana
;
Korea
;
New Jersey
;
Survival Rate
;
Tibia
8.Urinary diversion in conjunction with radical cystectomy in bladder cancer patient.
Korean Journal of Urology 1993;34(4):635-641
Several different methods of urinary diversion currently are available in conjunction with radical cystectomy. We reviewed our last 30 months of experience with diversion in 56 patients with bladder cancer undergoing surgery from May, 1990 through October. 1992 and focused on the decision- making process used to select the type of diversion. The results obtained were as follows. 1. Of the 56 patients. 27 patients had a diversion with an external appliance (26 via an ileal conduit and 1 via a cutaneous ureterostomy), 15 patients had a diversion with a continent urinary reservoir(Indiana pouch) and 14 patients had a diversion with an internal reservoir anastomosed to the urethra( 13 via an ileocolic neobladder and 1 via a Camey procedure). 2. The ileal conduit was evenly performed during the period. But the Indiana pouch was more performed between May 1990 and April 1991 and the ileocolic neobladder was mainly per formed since May 1991. 3. There were 50 men and 6 women. The majority of female patients (83%) underwent the Indiana pouch. The ileocolic neobladder was performed in patients who were relatively young and in good medical condition. 4. Urodynamic studies of the Indiana pouch and ileocolic neobladder performed at 6 months postoperatively showed low pressure, large capacity reservoir and high outlet (plicated ileum or urethra) resistance. All patients achieved satisfactory continence during the day. However.1 or 13 patients who underwent the ileocolic neobladder was incontinent at night. In conclusion. there are inherent advantages and disadvantages to each form of urinary diversion. Our general policy is the ileal conduit remains the most wise diversion in most patients but the alternative methods may be reasonable in certain circumstances and patients selection will be important to identify the most appropriate method of diversion for individual. Though the follow-up period is not long enough. Indiana pouch and ileocolic neobladder met the demands for ideal form of urinary diversion. With improvement in the technical aspects or the continent and internal functional reservoir, the number of patients having these reservoirs will increase.
Cystectomy*
;
Female
;
Follow-Up Studies
;
Humans
;
Ileum
;
Indiana
;
Male
;
Urinary Bladder Neoplasms*
;
Urinary Bladder*
;
Urinary Diversion*
;
Urodynamics
9.Efficient packaging retrovirus and construction of transgenic chicken technical platform.
Chaolai MAN ; Qing ZHANG ; Yan CHEN ; Dahai ZHU
Journal of Biomedical Engineering 2007;24(5):1111-1117
Transgenic chicken and oviduct bioreactor are growing to be one of the hotspot of scientific study in the field of biology. The most successful method of producing transgenic chicken is pseudotyped retrovirus vector system, but no one has reported the production of transgenic chicken by retrovirus system recently in our country. In order to accelerate our study in this field, we introduced the relevant technical methods such as packaging retrovirus and vesicular stomatitis virus G glycoprotein (VSV-G) pseudotyped retrovirus, optimizing the conditions of packaging retrovirus, concentrating VSV-G pseudotyped retrovirus, helper virus assays, and microinjection of retrovirus. Furthermore, we successfully conducted in vivo study for detecting the marker gene EGFP of chicken embryo as well as in vitro study for detecting that gene of chicken embryo myoblast (CFM), thus we have provided an applied technical platform for studies of transgenic chicken in the future.
Animals
;
Animals, Genetically Modified
;
Chick Embryo
;
Chickens
;
genetics
;
DNA Primers
;
Genetic Vectors
;
genetics
;
Retroviridae
;
genetics
;
Vesicular stomatitis Indiana virus
;
genetics
10.Comparison of the Complications and Urodynamic Parameters for Orthotopic Bladder Substitution with using Ileocolic or Ileal Segments after Radical Cystectomy.
Kang Jun CHO ; Dong Wan SOHN ; Sae Woong KIM
Korean Journal of Urology 2007;48(5):494-499
PURPOSE: The objective of this study was to compare the complications and urodynamic parameters of the patients who underwent orthotopic bladder substitution with using ileocolic or ileal segments after radical cystectomy for treating invasive bladder cancer. MATERIALS AND METHODS: Between January 1990 and April 2006, 260 patients with invasive bladder cancer underwent radical cystectomy and construction of the urinary diversion; ileal conduit, indiana pouch, ileocolic neobladder, ileal neobladder were all done at St. Mary's Hospital. The mean age of the patient was 61.8 years (range: 46-86). The ratio of male and female was 88%/12%. Forty nine patients received an orthotopic ileocolic neobladder and 45 patients received an orthotopic ileal neobladder. The complications and urodynamic parameters were compared in both groups. RESULTS: The orthotopic ileocolic neobladder after radical cystectomy for treating invasive bladder cancer has been performed between 1990 and 1996 and the orthotopic ileal neobladder has been performed between 1996 and 2006. Ileocolic neobladder related complications developed in 10 patients; neobladder leakage in 1 (2%), neobladder rupture in 1 (2%), stricture of the ureteroenteric anastomosis site in 4 (8.2%), and stricture of the urethral anastomosis site in 4 (8.2%). Ileal neobladder related complications developed in 11 patients; ureteroenteric stricture in 7 (15.5%), stricture of the urethral anastomosis site in 3 (6.6%) and acute pyelonephritis in 1 (2.2%). The results of the mean maximal flow rate and mean postvoid residual volume were better in the ileal neobladder group than those in the ileocolic neobladder group. CONCLUSIONS: There were no significant differences in complications between ileocolic neobladder and ileal neobladder. The maximal uroflow and residual urine volume of the ileal neobladder were superior to those of the ileocolic neobladder on urodynamic study.
Colon
;
Constriction, Pathologic
;
Cystectomy*
;
Female
;
Humans
;
Ileum
;
Indiana
;
Male
;
Pyelonephritis
;
Residual Volume
;
Rupture
;
Urinary Bladder Neoplasms
;
Urinary Bladder*
;
Urinary Diversion
;
Urodynamics*