• Korean Circulation Journal
• /
• v.52 no.3
• /
• pp.205-217
• /
• 2022

Background and Objectives: The prognostic value of left atrial (LA) function in terms of long-term clinical outcomes after mitral regurgitation (MR) surgery remains unclear. Therefore, we investigated the impact of preoperative LA global longitudinal strain (LAGLS) on the long-term postoperative clinical outcomes in chronic severe MR patients who underwent mitral valve (MV) repair surgery. Methods: From January 2012 to December 2017, we analyzed 338 patients (mean age, 51.9±12.5 years; 218 males [64.5%]) treated with MV repair surgery for severe MR. The primary outcome was cardiovascular events, defined as the composite of all-cause death, newly developed atrial fibrillation (AF), and re-hospitalization for cardiovascular causes. Results: During a median follow-up of 45 months (interquartile range, 26-65), 30 (8.9%) cardiovascular events, 5 (1.5%) all-cause death, 8 (2.4%) newly developed AF, and 26 (7.7%) re-hospitalizations occurred. On multivariable analysis, baseline LAGLS was an independent predictor of cardiovascular events (adjusted hazard ratio [HR], 0.91; 95% confidential interval [CI], 0.85-0.97; p=0.004) and re-hospitalization (adjusted HR, 0.93; 95% CI, 0.86-1.00; p=0.037). According to the optimal cutoff value of LAGLS, patients with low LAGLS (<23.6%) had a significantly higher risk of cardiovascular events (adjusted HR, 2.70; 95% CI, 1.04-7.00; p=0.041) than those with high LAGLS (≥23.6%). In a subgroup analysis, patients with high LAGLS had better clinical outcomes regardless of whether the patient had a LA volume index <60 mL/m². Conclusions: In patients with chronic severe MR who received successful MV repair surgery, preoperative LAGLS is an independent predictor of long-term postoperative outcomes.

• Korean Journal of Radiology
• /
• v.25 no.8
• /
• pp.756-766
• /
• 2024

Objective: To evaluate the efficacy and safety of thermal ablation in treating solitary low-risk T2N0M0 papillary thyroid cancer (PTC) and compare the outcomes of microwave ablation (MWA) and radiofrequency ablation (RFA). Materials and Methods: This retrospective, single center study involved 34 patients (age: 40.0 ± 13.9 years; 28 female) who had low-risk T2N0M0 PTC with a maximum diameter >2 cm and ≤4 cm and underwent MWA (n = 15) or RFA (n = 19) from November 2016 to April 2023. The primary outcomes were the cumulative rate of disease progression and delayed surgery rates. In contrast, the secondary outcomes included changes in tumor size, cumulative rate of complete tumor disappearance, and complication rates. Results: The median follow-up period was 18.0 months (interquartile range [IQR]: 9.0-40.0 months). At 12 months, the median volume reduction rate of the ablation zone was 74.2% (IQR: 53.7%-86.0%). Disease progression was noted in two patients within 1 year, including one patient with local tumor progression post-RFA and one with a new tumor post-MWA, resulting in a constant cumulative disease progression rate of 8.8% (95% confidence interval [CI]: 0%-19.8%) throughout the remaining follow-up period. Both patients were subsequently treated with additional ablation and did not require surgery. The cumulative rates of complete tumor disappearance at 1, 3, and 5 years were 4.0% (95% CI: 0%-11.4%), 26.8% (95% CI: 2.7%-44.9%), and 51.2% (95% CI: 0%-79.1%), respectively. No significant differences were observed in the disease progression (P = 0.829) or complete tumor disappearance (P = 0.633) rates between the MWA and RFA groups. Complications occurred in 14.7% (5/34) of patients presenting with transient hoarseness. RFA had a higher but not statistically significant complication rate than MWA did (21.1% [4/19] vs. 6.7% [1/15]; P = 0.355). Conclusion: Both MWA and RFA demonstrated promising short-term outcomes in terms of efficacy and safety in treating solitary low-risk T2N0M0 PTC, with no significant differences.

• Progress in Medical Physics
• /
• v.25 no.3
• /
• pp.167-175
• /
• 2014

The purpose of this study is to evaluate the variation of the dose which is delivered to the patients with glottis cancer under IMRT (intensity modulated radiation therapy) by using the 3D registration with CBCT (cone beam CT) images and the DIR (deformable image registration) techniques. The CBCT images which were obtained at a one-week interval were reconstructed by using B-spline algorithm in DIR system, and doses were recalculated based on the newly obtained CBCT images. The dose distributions to the tumor and the critical organs were compared with reference. For the change of volume depending on weight at 3 to 5 weeks, there was increased of 1.38~2.04 kg on average. For the body surface depending on weight, there was decreased of 2.1 mm. The dose with transmitted to the carotid since three weeks was increased compared be more than 8.76% planned, and the thyroid gland was decreased to 26.4%. For the physical evaluation factors of the tumor, PITV, TCI, rDHI, mDHI, and CN were decreased to 4.32%, 5.78%, 44.54%, 12.32%, and 7.11%, respectively. Moreover, $D_{max}$, $D_{mean}$, $V_{67.50}$, and $D_{95}$ for PTV were increased or decreased to 2.99%, 1.52%, 5.78%, and 11.94%, respectively. Although there was no change of volume depending on weight, the change of body types occurred, and IMRT with the narrow composure margin sensitively responded to such a changing. For the glottis IMRT, the patient's weight changes should be observed and recorded to evaluate the actual dose distribution by using the DIR techniques, and more the adaptive treatment planning during the treatment course is needed to deliver the accurate dose to the patients.

• Clinical and Experimental Reproductive Medicine
• /
• v.34 no.3
• /
• pp.159-166
• /
• 2007

Objective: To investigate whether semen parameters in infertile couples who undergone intrauterine insemination (IUI) change in the subsequent IUI cycle and the subsequent in vitro fertilization (IVF) cycle. Methods: Fifty-three infertile couples who had failed to become pregnant after the first IUI cycle with computer-assisted semen analysis (CASA) were included. After the first IUI, thirty-eight couples underwent the second IUI (Group 1), and fifteen underwent IVF-ET procedure (Group 2). All semen parameters including semen volume, concentration, motility and total motile sperm count were analyzed in the second IUI or IVF-ET procedure for comparison with the result of first IUI. Results: There were no significant differences in husband age, interval between the first and second procedure and cause of infertility. In Group 1, only sperm motility at the time of the latter IUI was significantly decreased when compared to the former IUI irrespective of the first semen parameters. In Group 2, sperm concentration, motility and total motile sperm count at the time of subsequent IVF were lower than the former IUI. By sub-analyses of Group 2, in the group of optimal semen parameter at IUI cycle, sperm concentration and total motile sperm count at the time of subsequent IVF were lower than the former IUI, while in the group of suboptimal semen parameter at IUI cycle, only sperm motility at the time of subsequent IVF were lower than the former IUI. Conclusion: The semen parameters in couples converted to IVF cycle were more adversely affected than those remained in IUI cycle. Further study on psychological stress should be necessary to explain the reason.

• The Journal of Korean Society for Radiation Therapy
• /
• v.30 no.1_2
• /
• pp.73-81
• /
• 2018

Purpose : The aims of this study were to compare and assess the effectiveness of Volumetric Modulated Arc Therapy(VMAT) using jaw tracking(JT) and fixed jaw(FJ) in radiation therapy of multiple brain metastasis. Methode and material : Among the patients with Multiple Brain Metastasis treated with jaw tracking, 10 patients with more than 6 tumors and with the size of radiation field $14{\times}14cm^2$ or more were included. Each Treatment plans with jaw tracking(JT) and fixed jaw(FJ) was established with Eclipse (Ver. 13.6 Varian, USA). Gamma Index (3 mm, 3 % confidence interval - 95 %) and maximum dose difference were measured with an electronic portal imaging device(EPID). The $D_{max}$ and $D_{mean}$ of Organ At Risk(OAR) were assessed and compared, and the Conformity Index(CI) and Homogeneity Index(HI) were evaluated. Result : Evaluating jaw tracking(JT) and fixed jaw(FJ) outcomes, in all cases, Gamma Index met the permissible standard of 3 mm, 3 % confidence intervals of 95 %. The maximum dose difference value from the areas with leaf end transmission was measured at a maximum of 98.4 % and an average of 43.6 % in clockwise(CW), and 67.9 % and 41.0 % for each in Counter-Clockwise(CCW). With jaw tracking, the maximum value of $D_{max}$ for each normal organ in OAR decreased in 15.36 %~74.59 % with the average value decreasing in 2.84 %~39.80 %. The maximum value of $D_{mean}$ in OAR decreased in 27.90 %~65.23 %, with the average value decreasing in 7.70 %~41.71 %. No change has been found in Conformity Index and Homogeneity Index values. Conclusion : When Jaw tracking is used in treating patients with multiple brain metastasis with VMAT, the unnecessary exposure due to leakage and transmission of radiation in unspecified areas was reduced, without affecting the dose distribution of the planning target volume(PTV), and the availability of radiation therapy with lower doses in normal organs is expected.

• Journal of Korea Port Economic Association
• /
• v.37 no.2
• /
• pp.73-89
• /
• 2021

The handysize bulk carriers are capable of transporting a variety of cargo that cannot be transported by mid-large size ship, and the spot chartering market is active, and it is a market that is independent of mid-large size market, and is more risky due to market conditions and charterage variability. In this study, Granger causality test, the Impulse Response Function(IRF) and Forecast Error Variance Decomposition(FEVD) were performed using monthly time series data. As a result of Granger causality test, coal price for coke making, Japan steel plate commodity price, hot rolled steel sheet price, fleet volume and bunker price have causality to Baltic Handysize Index(BHSI) and charterage. After confirming the appropriate lag and stability of the Vector Autoregressive model(VAR), IRF and FEVD were analyzed. As a result of IRF, the three variables of coal price for coke making, hot rolled steel sheet price and bunker price were found to have significant at both upper and lower limit of the confidence interval. Among them, the impulse of hot rolled steel sheet price was found to have the most significant effect. As a result of FEVD, the explanatory power that affects BHSI and charterage is the same in the order of hot rolled steel sheet price, coal price for coke making, bunker price, Japan steel plate price, and fleet volume. It was found that it gradually increased, affecting BHSI by 30% and charterage by 26%. In order to differentiate from previous studies and to find out the effect of short term lag, analysis was performed using monthly price data of major cargoes for Handysize bulk carriers, and meaningful results were derived that can predict monthly market conditions. This study can be helpful in predicting the short term market conditions for shipping companies that operate Handysize bulk carriers and concerned parties in the handysize chartering market.

• Journal of Chest Surgery
• /
• v.29 no.5
• /
• pp.495-503
• /
• 1996

The bidirectional cavopulmonary shunt may be useful as an intermediate procedure before Fontal oper- ation in high-risk patients, because it provides adequate relief of cyanosis and relief of ventricular volume overload. But there are no established theory about the effects of bidirectional cavopulmonary shunt on pulmonary arterial development. The purpose of this article is a study of changes of pulmonary artery size after bidirectional cavopulmonary shunt. Ca diac catheterization and angiography procedures were done on 19 patients who underwent bidirectional cavopulmonary shunt from February 1992 to July 1994, their results were reviewed. Preoperative cardiac catheterization and angiography procedures were performed at a mean interval of ).8 $\pm$4.8($\pm$SEM) months before surgery and following catheterization at a mean postoperative interval of 19.6 $\pm$4.8 months. Pulmonary arterial sixte measurement were standardized for body surface area(Pulmon- arty artery index), and for diameter of descending thoracic aorta(McGoon ratio). Patient's age, body stir- face area, pulmonary angioplasty, preoperative McGoon ratio and follow-up intervals were considered as variables. Before bidirectional cavopulmonary shunt, patient's mean age, body surface area, arterial 02 saturation, diameter of right pulmonary artery, diameter of left pulmonary artery, pulmonary artery Index, McGoon ratio were 13.7$\pm$15.6 months, 0.40$\pm$0.12m2, 71.4$\pm$12.4m2, 7.1$\pm$1.7mm, 6.2$\pm$1 , 191.8$\pm$82.7mm21m2, 1.73 $\pm$0.49, respectively. After bidirectional cavopulmonary shunt, the values were changed to 39.9 $\pm$ 16.2 months, 0.58$\pm$0.07 m2, 83.0$\pm$3.8m2, 9.0$\pm$ 1.5 mm, 7.7$\pm$2.0, 197.3$\pm$57.1 mm2/m2, 1.76$\pm$0.32, respect- ively With patients'development (age, body surf'ace area), diameters of pulmonary arteries were increased, but pulmonary artery indices and McGoon ratios were not changed. And there were no effects of age, body surf'ace area, amount of increased 02 saturation, pulmonary angiography and follow-up duration on the increment of pulmonary ar- tery size. But when the McGoon ratio was as low as 1.2, there were significant increase in postoperative pulmonary artery sizes. There was a significant correlation between preoperative pulmonary artery index (PAI) and McGoon ratio (MGR) ; PAI : MGRxl18.0-12.4 In conclusion, bidirectional cavopulmonary shunt provides adequate increment of arterial 02 saturation and does not increase the pulmonary artery size. Further investi ation is mandatory to evaluate the effect of pulsatile bidirectional cavopulmonary shunt on pulmonary artery growth.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.14 no.1
• /
• pp.115-121
• /
• 2010

Purpose: The purpose of this study is to measure F-18 FDG with two different types of dose calibrator measuring radionuclide and radioactivity and investigate the effect of F-18 FDG on SUV (Standard Uptake Value) in human body. Materials and Methods: Two different dose calibrators used in this study are CRC-15 Dual PET (Capintec) and CRC-15R (Capintec). Inject 1 mL, 2 mL, 3 mL of F-18 FDG into three 2 mL syringes, respectively, and measure initial radioactivity from each dose calibrator. Then measure and record radioactivity at 30 minute interval for 270 minutes. According to the initial radioactivity, linearity between decay factor driven from radioactive decay formula and the values measured by dose calibrator have been analyzed by simple linear regression. Fine linear regression line optimizing values measured with CRC-15 through regression analysis on the basis of the volume of which the measured value is close to the most ideal one in CRC-15 Dual PET. Create ROI on lung, liver, and region part of 50 persons who has taken PET/CT test, applying values from linear regression equation, and find SUV. We have also performed paired t-test to examine statistically significant difference in the radioactivity measured with CRC-15 Dual PET, CRC-15R and its SUV. Results: Regression analysis of radioactivity measured with CRC-15 Dual PET and CRC-15R shows results as follows: in the case 1 mL, the r statistic representing correlation was 0.9999 and linear regression equation was y=1.0345x+0.2601; in 2 mL case, r=0.9999, linear regression equation y=1.0226x+0.1669; in 3 mL case, r=0.9999, linear regression equation y=1.0094x+0.1577. Based on the linear regression equation from each volume, t-test results show significant difference in SUV of ROI in lung, liver, region part in all three case. P-values in each case are as follows: in 1 mL case, lung, liver and region (p<0.0001); in 2 mL case, lung (p<0.002), liver and region (p<0.0001); in 3 mL case, lung (p<0.044), liver and region (p<0.0001). Conclusion: Radioactivity measured with CRC-15 Dual PET, CRC-15R, dose calibrator for F-18 FDG test, do not show difference correlation, while these values infer that SUV has significant differences in the aspect of uptake in human body. Therefore, it is necessary to consider the difference of SUV in human body when using these dose calibrator.

• Journal of Chest Surgery
• /
• v.38 no.5 s.250
• /
• pp.323-334
• /
• 2005

Background: Gene therapy is a new and promising option for the treatment of severe myocardial ischemia by therapeutic angiogenesis. The goal of this study was to elucidate the efficacy of therapeutic angiogenesis by using VEGF165 in large animals. Material and Method: Twenty-one pigs that underwent ligation of the distal left anterior descending coronary artery were randomly allocated to one of two treatments: intramyocardial injection of pCK-VEGF (VEGF) or intramyocardial injection of pCK-Null (Control). Injections were administered 30 days after ligation. Seven pigs died during the trial, but eight pigs from VEGF and six from Control survived. Echo-cardiography was performed on day 0 (preoperative) and on days 30 and 60 following coronary ligation. Gated myocardial single photon emission computed tomography imaging (SPECT) with $^{99m}Tc-labeled$ sestamibi was performed on days 30 and 60. Myocardial perfusion was assessed from the uptake of $^{99m}Tc-labeled$ sestamibi at rest. Global and regional myocardial function as well as post-infarction left ventricular remodeling were assessed from segmental wall thickening; left ventricular ejection fraction (EF); end systolic volume (ESV); and end diastolic volume (EDV) using gated SPECT and echocardiography. Myocardium of the ischemic border zone into which pCK plasmid vector had been injected was also sampled to assess micro-capillary density. Result: Micro-capillary density was significantly higher in the VEGF than in Control ($386\pm110/mm^{2}\;vs.\;291\pm127/mm^{2};\;p<0.001$). Segmental perfusion increased significantly from day 30 to day 60 after intramyocardial injection of plasmid vector in VEGF ($48.4\pm15.2\%\;vs.\;53.8\pm19.6\%;\;p<0.001$), while no significant change was observed in the Control ($45.1\pm17.0\%\;vs.\;43.4\pm17.7\%;\;p=0.186$). This resulted in a significant difference in the percentage changes between the two groups ($11.4\pm27.0\%\;increase\;vs.\;2.7\pm19.0\%\;decrease;\;p=0.003$). Segmental wall thickening increased significantly from day 30 to day 60 in both groups; the increments did not differ between groups. ESV measured using echocardiography increased significantly from day 0 to day 30 in VEGF ($22.9\pm9.9\;mL\;vs.\;32.3\pm9.1\;mL;\; p=0.006$) and in Control ($26.3\pm12.0\;mL\;vs.\;36.8\pm9.7\;mL;\;p=0.046$). EF decreased significantly in VEGF ($52.0\pm7.7\%\;vs.\;46.5\pm7.4\%;\;p=0.004$) and in Control ($48.2\pm9.2\%\;vs.\;41.6\pm10.0\%;\;p=0.028$). There was no significant change in EDV. The interval changes (days $30\~60$) of EF, ESV, and EDV did not differ significantly between groups both by gated SPECT and by echocardiography. Conclusion: Intramyocardial injection of pCK-VEGF165 induced therapeutic angiogenesis and improved myocardial perfusion. However, post-infarction remodeling and global myocardial function were not improved.

• Progress in Medical Physics
• /
• v.17 no.3
• /
• pp.131-135
• /
• 2006

A commercial ion chamber matrix was examined the characteristics and its performance for radiotherapy qualify assurance. The device was the I'mRT 2D-MatriXX (Scanditronix-Wellhofer, Schwarzenbruck, Germany). The 2D-MatriXX device consists of a 1020 vented ion chamber array, arranged in $24{\times}24cm^2$ matrix. Each ion chamber has a volume of $0.08cm^3$, spacing of 0.762 cm and minimum sampling time of 20 ms. For the investigation of the characteristics, dose linearity, output factor, short-term reproducibility and dose rate dependency were tested. In the testing of dose linearity. It has shown a good signal linearity within 1% in the range of $1{\sim}800$cGy. Dose rate dependency was found to be lower than 0.4% (Range: 100-600 Mu/min) relative to a dose rate of 300 Mu/min as a reference. Output factors matched very well within 0.5% compared with commissioned beam data using a ionization chamber (CC01, Scanditronix-Wellhofer, Schwarzenbruck, Germany) in the range of field sizes $3{\times}3{\sim}24{\times}24cm^2$. Short-term reproducibility (6 times with a interval of 15 minute) was also shown a good agreement within 0.5%, when the temperature and the pressure were corrected by each time of measurement. in addition, we compared enhanced dynamic wedge (EDW, Varian, Palo Alto, USA) profiles from calculated values in the radiation planning system with those from measurements of the MatriXX. Furthermore, anon-uniform IMRT dose fluence was tested. All the comparison studies have shown good agreements. In this study, the MatriXX was evaluated as a reliable dosimeter, and it could be used as a simplistic and convenient tool for radiotherapy qualify assurance.