Search tips
Search criteria

Results 1-12 (12)

Clipboard (0)

Select a Filter Below

Year of Publication
1.  Current Status of Brachytherapy for Prostate Cancer 
Korean Journal of Urology  2012;53(11):743-749.
Brachytherapy was developed to treat prostate cancer 50 years ago. Current advanced techniques using transrectal ultrasonography were established 25 years ago. Transrectal ultrasound (TRUS) has enabled the prostate to be viewed with improved resolution with the use of modern ultrasound machines. Moreover, the development of software that can provide images captured in real time has improved treatment outcomes. Other new radiologic imaging technologies or a combination of magnetic resonance and TRUS could be applied to brachytherapy in the future. The therapeutic value of brachytherapy for early-stage prostate cancer is comparable to that of radical prostatectomy in long-term follow-up. Nevertheless, widespread application of brachytherapy cannot be achieved for several reasons. The treatment outcome of brachytherapy varies according to the skill of the operator and differences in patient selection. Currently, only three radioactive isotopes are available for use in low dose rate prostate brachytherapy: I-125, Pd-103, and Cs-131; therefore, more isotopes should be developed. High dose rate brachytherapy using Ir-192 combined with external beam radiation, which is needed to verify the long-term effects, has been widely applied in high-risk patient groups. Recently, tumor-selective therapy or focal therapy using brachytherapy, which is not possible by surgical extraction, has been developed to maintain the quality of life in selected cases. However, this new application for prostate cancer treatment should be performed cautiously because we do not know the oncological outcome, and it would be an interim treatment method. This technique might evolve into a hybrid of whole-gland treatment and focal therapy.
PMCID: PMC3502731  PMID: 23185664
Brachytherapy; Neoplasms; Prostate
2.  Association between R.E.N.A.L. nephrometry score and perioperative outcomes following open partial nephrectomy under cold ischemia 
We investigate the clinical significance of the R.E.N.A.L. nephrometry score for renal neoplasm following open partial nephrectomy (PN) under cold ischemia.
A retrospective analysis was conducted using clinical data of 98 consecutive patients with clear cell renal cell carcinoma who underwent open PN by a single surgeon from December 2000 to September 2012. Tumour complexity was stratified into 3 categories: low (4–6), moderate (7–9) and high (10–12) complexity. Perioperative outcomes, such as complications, cold ischemic time, estimated blood loss and renal function, were analyzed according to the complexity by NS. Complications were stratified using the Clavien-Dindo classification system.
Tumour complexity according to nephrometry score was assessed as low in 16 (16.3%), moderate in 48 (49.0%) and high in 34 (34.7%). The median cold ischemic time did not differ significantly among the 3 groups (36.0 minutes in low-, 40 minutes in moderate- and 43 minutes in the high-complexity group, p = 0.421). Total complications did not differ significantly (2 (2.0%) in low, 4 (4.1%) in moderate and 4 (4.1%) in high, p = 0.984). Each Grade 3 complication occurred in the moderate (urine leakage) and high groups (lymphocele). Postoperative renal functional outcomes were similar among the groups (p = 0.729). Only mean estimated blood loss was significantly different with nephrometry score (p = 0.049).
The nephrometry score, as used in an open PN series under cold ischemia, was not significantly associated with perioperative outcomes (i.e., ischemia time, complications, renal functional preservation).
PMCID: PMC3956832  PMID: 24678352
3.  Simple Use of the Suppository Type Povidone-Iodine Can Prevent Infectious Complications in Transrectal Ultrasound-Guided Prostate Biopsy 
Advances in Urology  2009;2009:750598.
Purpose. To determine the effect of simple use of suppository povidone-iodine on infectious complications after transrectal ultrasonography-guided biopsy of the prostate. Methods. All 481 patients are included and received antibiotic prophylaxis. Among them, 360 patients received povidone-iodine suppository (Gynobetadine; 200 mg) immediately prior to biopsy and 121 patients did not. Infectious complications were classified. To evaluate bactericidal effects, we counted bacterial colonies in the rectum, harvested from a rectal swab before insertion of the suppository and after biopsy. Aliquots of the suspended bacterial strains were added to Mueller-Hinton agar medium for incubation. Colony counts were determined. Results. Infectious complications developed in 1 case (0.3%) in the rectal preparation group (Group 1) and in 8 cases (6.6%) in the nonrectal preparation group (Group 2). One in Group 1 had a fever without sepsis. Two patients had sepsis and six had fever without sepsis in Group 2. Rectal preparation was a statistically significant risk factor influencing the development of infectious complications. In vitro experiments, the mean number of colony-forming units decreased 99.9% after the rectal povidone-iodine preparation. Conclusions. All through the biopsy, povidone-iodine melted into the rectum and decreased the bacterial colony count. Simple use of povidone-iodine suppository before prostate biopsy minimizes the risk of infectious complications.
PMCID: PMC2673474  PMID: 19404480
4.  Evaluation of Short Term Clinical Effects and Presumptive Mechanism of Botulinum Toxin Type A as a Treatment Modality of Benign Prostatic Hyperplasia 
Yonsei Medical Journal  2006;47(5):706-714.
The purpose of this study was to evaluate the effect and investigate the putative mechanism of botulinum toxin type A (BTA) applied to the treatment of benign prostatic hyperplasia (BPH). A total of 52 patients with symptomatic BPH were evaluated. Transperineal intraprostatic injection under transrectal ultrasonography was carried out. BTA dissolved in 4 to 9 mL of saline was used from 100 U to 300 U, according to prostate volume. Twenty-six patients received only BTA (BT group), and 26 received both BTA and one month of an α-adrenergic antagonist (BTα group). The therapeutic outcomes were evaluated by comparing parameters such as international prostate symptom score (IPSS), quality of life, prostate specific antigen, prostate volume, post-void residual urine, and peak urinary flow rate. At the one month follow-up, 18 patients in the BT group and 21 in the BTα group had subjective symptomatic relief (p = 0.337). Only IPSS5 (weak stream) was significantly different between the BT group and BTα groups (p = 0.034). At the three month follow-up, 39 patients had subjective symptomatic relief. The storage symptoms were improved more than the voiding symptoms. Additionally, about 50 percent of the patients whose voiding symptom improved expressed improved erectile function. BTA injection seems to be an alternative treatment for BPH. The differences after the one month evaluation between the BT and the BTα groups might suggest that the adrenergic influence could be relatively reinforced by the anticholinergic effect of BTA. Nitric oxide would thus be involved in a BTA action mechanism in BPH.
PMCID: PMC2687757  PMID: 17066515
Botulinum toxin type A; benign prostatic hyperplasia; neurotransmitter
5.  Clinical Factors That Predict Successful Posterior Urethral Anastomosis With a Gracilis Muscle Flap 
Korean Journal of Urology  2013;54(10):710-714.
We evaluated the preoperative clinical factors that affect the surgical outcome of posterior urethral anastomosis (PUA) with a gracilis muscle flap (GMF) to determine which factors predict benefit from the use of the GMF.
Materials and Methods
This was a retrospective analysis of 49 patients who underwent a delayed PUA with a GMF. A successful clinical outcome was defined as achieving a peak urinary flow rate greater than 15 mL/s at 3 and 12 months postoperatively without evidence of stricture recurrence on a retrograde urethrogram or cystourethroscopy at 3 months postoperatively. Multiple clinical factors were evaluated by use of univariate and multivariate analyses.
The outcome of 21 of 49 patients (42.9%) was deemed successful. The mean age of the 49 patients was 37.2±13.5 years and the mean follow-up duration was 43.4±28.0 months. The length of the urethral defect was significantly shorter in patients with a successful outcome than in patients with an unsuccessful outcome (p=0.010). The outcome differed significantly depending on whether the patients had a previously successful urethroplasty (p=0.036) or whether they had suffered a pelvic bone injury (p=0.012). Multivariate logistic regression analyses revealed that a previous urethroplasty was the only preoperative clinical factor that significantly affected the surgical outcome in PUA with a GMF (odds ratio, 0.218; 95% confidence interval, 0.050 to 0.947; p=0.042).
A history of previous urethroplasty is a preoperative clinical factor that significantly affects the surgical outcome in PUA with a GMF; the procedure is more likely to be successful in patients who have not previously undergone urethroplasty.
PMCID: PMC3806997  PMID: 24175047
Surgical anastomosis; Surgical flap; Urethral stricture
6.  Outcomes of Gleason Score ≤8 among High Risk Prostate Cancer Treated with 125I Low Dose Rate Brachytherapy Based Multimodal Therapy 
Yonsei Medical Journal  2013;54(5):1207-1213.
To investigate the role of low dose rate (LDR) brachytherapy-based multimodal therapy in high-risk prostate cancer (PCa) and analyze its optimal indications.
Materials and Methods
We reviewed the records of 50 high-risk PCa patients [clinical stage ≥T2c, prostate-specific antigen (PSA) >20 ng/mL, or biopsy Gleason score ≥8] who had undergone 125I LDR brachytherapy since April 2007. We excluded those with a follow-up period <3 years. Biochemical recurrence (BCR) followed the Phoenix definition. BCR-free survival rates were compared between the patients with Gleason score ≥9 and Gleason score ≤8.
The mean initial PSA was 22.1 ng/mL, and mean D90 was 244.3 Gy. During a median follow-up of 39.2 months, biochemical control was obtained in 72% (36/50) of the total patients; The estimated 3-year BCR-free survival was 92% for the patients with biopsy Gleason scores ≤8, and 40% for those with Gleason scores ≥9 (p<0.001). In Cox multivariate analysis, only Gleason score ≥9 was observed to be significantly associated with BCR (p=0.021). Acute and late grade ≥3 toxicities were observed in 20% (10/50) and 36% (18/50) patients, respectively.
Our results showed that 125I LDR brachytherapy-based multimodal therapy in high-risk PCa produced encouraging relatively long-term results among the Asian population, especially in patients with Gleason score ≤8. Despite small number of subjects, biopsy Gleason score ≥9 was a significant predictor of BCR among high risk PCa patients after brachytherapy.
PMCID: PMC3743192  PMID: 23918571
Prostate cancer; brachytherapy; high risk group; biochemical recurrence
7.  Reversible Infertility Associated with Testosterone Therapy for Symptomatic Hypogonadism in Infertile Couple 
Yonsei Medical Journal  2013;54(3):702-706.
Androgen replacement therapy has been shown to be safe and effective for most patients with testosterone deficiency. Male partners of infertile couples often report significantly poorer sexual activity and complain androgen deficiency symptoms. We report herein an adverse effect on fertility caused by misusage of androgen replacement therapy in infertile men with hypogonadal symptoms.
Materials and Methods
The study population consisted of 8 male patients referred from a local clinic for azoospermia or severe oligozoospermia between January 2008 and July 2011. After detailed evaluation at our andrology clinic, all patients were diagnosed with iatrogenic hypogonadism associated with external androgen replacement. We evaluated changes in semen parameters and serum hormone level, and fertility status.
All patients had received multiple testosterone undecanoate (NebidoR) injections at local clinic due to androgen deficiency symptoms combined with lower serum testosterone level. The median duration of androgen replacement therapy prior to the development of azoospermia was 8 months (range: 4-12 months). After withdrawal of androgen therapy, sperm concentration and serum follicle-stimulating hormone level returned to normal range at a median 8.5 months (range: 7-10 months).
Misusage of external androgen replacement therapy in infertile men with poor sexual function can cause temporary spermatogenic dysfunction, thus aggravating infertility.
PMCID: PMC3635615  PMID: 23549818
Androgen; male infertility; hypogonadism
8.  LiNi0.4Co0.3Mn0.3O2 thin film electrode by aerosol deposition 
LiNi0.4Co0.3Mn0.3O2 thin film electrodes are fabricated from LiNi0.4Co0.3Mn0.3O2 raw powder at room temperature without pretreatments using aerosol deposition that is much faster and easier than conventional methods such as vaporization, pulsed laser deposition, and sputtering. The LiNi0.4Co0.3Mn0.3O2 thin film is composed of fine grains maintaining the crystal structure of the LiNi0.4Co0.3Mn0.3O2 raw powder. In the cyclic voltammogram, the LiNi0.4Co0.3Mn0.3O2 thin film electrode shows a 3.9-V anodic peak and a 3.6-V cathodic peak. The initial discharge capacity is 44.6 μAh/cm2, and reversible behavior is observed in charge-discharge profiles. Based on the results, the aerosol deposition method is believed to be a potential candidate for the fabrication of thin film electrodes.
PMCID: PMC3264512  PMID: 22222001
thin film; aerosol deposition; battery
9.  A comparison of preplan MRI and preplan CT-based prostate volume with intraoperative ultrasound-based prostate volume in real-time permanent brachytherapy 
Radiation Oncology Journal  2011;29(3):199-205.
The present study compared the difference between intraoperative transrectal ultrasound (iTRUS)-based prostate volume and preplan computed tomography (CT), preplan magnetic resonance imaging (MRI)-based prostate volume to estimate the number of seeds needed for appropriate dose coverage in permanent brachytherapy for prostate cancer.
Materials and Methods
Between March 2007 and March 2011, among 112 patients who underwent permanent brachytherapy with 125I, 60 image scans of 56 patients who underwent preplan CT (pCT) or preplan MRI (pMRI) within 2 months before brachytherapy were retrospectively reviewed. Twenty-four cases among 30 cases with pCT and 26 cases among 30 cases with pMRI received neoadjuvant hormone therapy (NHT). In 34 cases, NHT started after acquisition of preplan image. The median duration of NHT after preplan image acquisition was 17 and 21 days for cases with pCT and pMRI, respectively. The prostate volume calculated by different modalities was compared. And retrospective planning with iTRUS image was performed to estimate the number of 125I seed required to obtain recommended dose distribution according to prostate volume.
The mean difference in prostate volume was 9.05 mL between the pCT and iTRUS and 6.84 mL between the pMRI and iTRUS. The prostate volume was roughly overestimated by 1.36 times with pCT and by 1.33 times with pMRI. For 34 cases which received NHT after image acquisition, the prostate volume was roughly overestimated by 1.45 times with pCT and by 1.37 times with pMRI. A statistically significant difference was found between preplan image-based volume and iTRUS-based volume (p < 0.001). The median number of wasted seeds is approximately 13, when the pCT or pMRI volume was accepted without modification to assess the required number of seeds for brachytherapy.
pCT-based volume and pMRI-based volume tended to overestimate prostate volume in comparison to iTRUS-based volume. To reduce wasted seeds and cost of the brachytherapy, we should take the volume discrepancy into account when we estimate the number of 125I seeds for permanent brachytherapy.
PMCID: PMC3429903  PMID: 22984671
Brachytherapy; Prostate cancer; Prostate volume
10.  Laparoscopic Treatment of Appendicovesical Fistula 
Yonsei Medical Journal  2010;51(3):463-465.
A 23-year-old man had a history of intermittent episodes of urinary tract infection with associated low abdominal pain for 15 years. Persistent bacteriuria even with prolonged antibiotics was the reason why he was referred to our hospital. Laboratory tests were normal except pyuria and growth of Escherichia coli in the urinary samples. Cystoscopy revealed a small slit-like opening on the right lateral wall of bladder dome. We found some air within the bladder and a suspicious communicating tract between the appendix and bladder on a CT scan. With a strong impression of appendicovesical fistula, a laparoscopy was performed to confirm a diagnosis and to remove the appendicovesical fistula resulting in a satisfactory result without any complication.
PMCID: PMC2852808  PMID: 20376905
Urinary tract infections; appendix; urinary bladder; fistula; laparoscopy
11.  Ureteroscopic Lithotripsy Using Swiss Lithoclast for Treatment of Ureteral Calculi: 12-Years Experience 
Journal of Korean Medical Science  2009;24(4):690-694.
Ureteroscopic lithotripsy using Swiss Lithoclast was performed in 411 cases from January 1996 to September 2007 in a single hospital. Medical records of 341 cases, in which Swiss Lithoclast was successfully applied, were available for this retrospective study. We used 9.5Fr and 10Fr Storz rigid ureteroscopes. A success was defined as being free of stone-related symptoms and residual stones larger than 2 mm. Sixty one stones were located in the upper ureter, 49 stones were in the mid ureter, and 231 stones were in the lower ureter. The overall success rate was 93.5%. The success rate of upper ureter stone (80.3%) was significantly lower compared with those of mid (93.8%) and lower (96.9%) ureter stones (P=0.001). The higher the calculi was located within the ureter, the more chance of upward migration there was (P<0.001). The success rate in male patients was lower than in female patients without a statistical significance (P=0.068). The success rate decreased as the size of the stone increased (P<0.001), and as the degree of hydronephrosis increased (P=0.03). Perforation rates were 4.9%, 4.1%, and 2.6% from upper to lower ureter stone group. Ureteroscopic lithotripsy using Swiss Lithoclast is a safe and useful treatment modality for ureteral calculi.
PMCID: PMC2719219  PMID: 19654954
Ureter; Calculi; Lithotripsy
12.  Piezoelectric and Magnetoelectric Thick Films for Fabricating Power Sources in Wireless Sensor Nodes 
Sensors (Basel, Switzerland)  2009;9(8):6362-6384.
In this manuscript, we review the progress made in the synthesis of thick film-based piezoelectric and magnetoelectric structures for harvesting energy from mechanical vibrations and magnetic field. Piezoelectric compositions in the system Pb(Zr,Ti)O3–Pb(Zn1/3Nb2/3)O3 (PZNT) have shown promise for providing enhanced efficiency due to higher energy density and thus form the base of transducers designed for capturing the mechanical energy. Laminate structures of PZNT with magnetostrictive ferrite materials provide large magnitudes of magnetoelectric coupling and are being targeted to capture the stray magnetic field energy. We analyze the models used to predict the performance of the energy harvesters and present a full system description.
PMCID: PMC3312449  PMID: 22454590
piezoelectric; magnetoelectric; energy harvesting; thick films; MEMS

Results 1-12 (12)