Objective: : Collateral circulation is associated with the differential treatment effect of endovascular thrombectomy (EVT) in acute ischemic stroke. We aimed to verify the ability of the collateral map to predict futile EVT in patients with acute anterior circulation ischemic stroke. Methods: : This secondary analysis of a prospective observational study included data from participants underwent EVT for acute ischemic stroke due to occlusion of the internal carotid artery and/or the middle cerebral artery within 8 hours of symptom onset. Multiple logistic regression analyses were conducted to identify independent predictors of futile recanalization (modified Rankin scale score at 90 days of 4–6 despite of successful reperfusion). Results: : In a total of 214 participants, older age (odds ratio [OR], 2.40; 95% confidence interval [CI], 1.56 to 3.67; p<0.001), higher baseline National Institutes of Health Stroke Scale (NIHSS) scores (OR, 1.12; 95% CI, 1.04 to 1.21; p=0.004), very poor collateral perfusion grade (OR, 35.09; 95% CI, 3.50 to 351.33; p=0.002), longer door-to-puncture time (OR, 1.08; 95% CI, 1.02 to 1.14; p=0.009), and failed reperfusion (OR, 3.73; 95% CI, 1.30 to 10.76; p=0.015) were associated with unfavorable functional outcomes. In 184 participants who achieved successful reperfusion, older age (OR, 2.30; 95% CI, 1.44 to 3.67; p<0.001), higher baseline NIHSS scores (OR, 1.12; 95% CI, 1.03 to 1.22; p=0.006), very poor collateral perfusion grade (OR, 4.96; 95% CI, 1.42 to 17.37; p=0.012), and longer door-to-reperfusion time (OR, 1.09; 95% CI, 1.03 to 1.15; p=0.003) were associated with unfavorable functional outcomes. Conclusion : The assessment of collateral perfusion status using the collateral map can predict futile EVT, which may help select ineligible patients for EVT, thereby potentially reducing the rate of futile EVT.

Background and Objectives: There have been no reports in Korea regarding cochlear implant surgeries using Cochlear Nucleus Profile Slim Modiolar electrode [CI532 (Cochlear Ltd.)], as it has been recently released in Korea. We aimed to investigate the short-term results of CI532 and compare them with previous devices with perimodiolar or straight electrodes arrays from the same manufacturer.Subjects and Method From August 2018 to July 2019, 52 patients (26 adults; 26 children) who underwent cochlear implantation of CI532 were included. The intraoperative impedance and evoked compound action potential (ECAP) threshold in each electrode were analyzed and compared with the devices with a perimodiolar electrode array [Contour Advance® (Cochlear Ltd.)] and a lateral wall electrode array [CI422 and CI522 (Cochlear Ltd.)]. Postoperative changes of hearing thresholds at each frequency (250, 500, and 1000 Hz) and aided word recognition scores (WRS) were also compared. Results: CI532 showed significantly lower intraoperative impedance in the basal regions compared to the lateral wall electrode array. The ECAP thresholds of CI532 in the apical electrodes were significantly lower than that in the other two groups. After implantation, CI532 showed a significant preservation of hearing thresholds at most frequencies and showed significantly higher preservation rates than the other electrodes. However, there was no difference between the three groups regarding the postoperative short-term aided WRS. Conclusion CI532 showed lower intraoperative impedances and ECAP thresholds, and better short-term hearing preservation outcomes compared to the other electrodes, suggesting that CI532 electrode might be a better option with less traumatic insertion. However, there was no significant difference in the aided WRS, and further studies with a longer follow-up are necessary to examine the difference of audiologic outcomes.

In this study, the effects of a mixture consisting of vitamin E, vitamin C, pycnogenol and evening primrose oil (mixture LGNC-5) on ultraviolet light (UV) induced pigmentation and wrinkle reductions of normal healthy volunteers were studied. In a double-blind placebo-controlled study, each of 54 subjects took daily either 4 capsules of the mixture LGNC-5 (Group ABC; 282.5 mg/capsule) or placebo (Group Ganada). We irradiated 2.5 MED UV on the upper arms and measured the whitening effect by colorimeter-based L value. The level of wrinkle reduction was determined by image analysis using skin replica around the crow' feet, and the level of serum vitamin E was determined at baseline and 12 weeks. After 12-week oral administration, the treated group showed a significant reduction in skin pigmentation and wrinkles compared with the placebo group (p = 0.011 and p = 0.000005 , respectively). Also, the level of serum vitamin E was significantly increased in the treated group after 12-week oral adminstration of the mixture compared with that in the placebo group (p = 0.0001). In conclusion, 12-week oral administration of LGNC-5 as a dietary supplement could be effective to reduce both UV induced pigmentation and skin wrinkle without side effects.
Administration, Oral ; Arm ; Ascorbic Acid ; Capsules ; Dietary Supplements ; Flavonoids ; Foot ; gamma-Linolenic Acid ; Humans ; Linoleic Acids ; Oenothera biennis ; Pigmentation ; Plant Oils ; Skin ; Skin Pigmentation ; Ultraviolet Rays ; Vitamin E ; Vitamins

PURPOSE: A skin-sparing mastectomy (SSM) with immediate reconstruction can give psychological and cosmetic benefits to patients requiring a mastectomy, but a risk of pulmonary thromboembolism (PTE) also exists due to longer operative time. The purpose of this study was to evaluate the clinical characteristics of symptomatic PTE following a SSM with immediate reconstruction. METHODS: Of 216 breast cancer patients underwent a SSM with immediate reconstruction at the Asan Medical Center, between December 2003 and July 2005, 7 in whom postoperative symptomatic PTE developed were included in this study. The ventilation/perfusion scan, embolism CT and serum D-dimer level were checked for those suspected of PTE. RESULTS: The prevalence of symptomatic PTE was 3.2% (7/216). Mean patient age and BMI were 41 years and 24.9 kg/m2, respectively. All patients had undergone TRAM reconstruction, with mean operative time of 562.1 minutes. Postoperative bleeding developed in 4 cases. The pathological stages included 0, I and IIA, which were observed in 1, 4 and 2 cases, respectively. Most common symptom of PTE was dyspnea, which developed in all patients on the second or third postoperative day; followed by chest discomfort and tachypnea. The ventilation/perfusion scans showed 6 with high probabilities. All seven patients were diagnosed as PTE on embolism CT. One patient had DVT on the lower extremities. The most common site of PTE was the superior lobar artery and the segmental branches of the right pulmonary artery. All patients recovered, or were recovering, after the LMWH and warfarin treatment. CONCLUSION: This study has shown that SSM with immediate reconstruction possesses a considerable risk of postoperative PTE. Further study on preoperative prophylaxis and the risk factors is warranted to prevent PTE.
Arteries ; Breast Neoplasms* ; Breast* ; Chungcheongnam-do ; Dyspnea ; Embolism ; Hemorrhage ; Heparin, Low-Molecular-Weight ; Humans ; Lower Extremity ; Mastectomy* ; Operative Time ; Prevalence ; Pulmonary Artery ; Pulmonary Embolism* ; Risk Factors ; Tachypnea ; Thorax ; Warfarin

PURPOSE: A skin-sparing mastectomy (SSM), followed by immediate reconstruction, which has aesthetic advantages, is being increasingly used to treat many early breast carcinomas; however, there are few data regarding the outcome and safety of this procedure. The objective of this study was to evaluate the safety of utilizing a SSM with immediate reconstruction compared with the outcome of a conventional mastectomy. METHODS: A retrospective review was performed on 169 patients who underwent a SSM with immediate reconstruction, and 2102 patients who received a conventional mastectomy between January 1996 and December 2002, at the Asan Medical Center. The patient and tumor characteristics, as well as the types of reconstruction, incidences of recurrence and survival rates were examined. RESULTS: The mean age of the SSM group was younger (39 vs. 47 years, p < 0.001), and the mean tumor size smaller than those of the mastectomy group (2.6 vs. 3.2cm, p = 0.002). Lymph node involvement was present in 39.6% and 48.4% of the SSM and mastectomy groups, respectively (p = 0.24). The proportion at early stages (0 and 1) in the SSM group was higher than those in the mastectomy group (50.9 vs. 30.7%, p < 0.001). In the high-risk patients, postoperative radiation was administered to 24.1 and 54.9% of the SSM and mastectomy group, respectively (p = 0.002). With a median follow-up of 41 months, the recurrence rates for the SSM and mastectomy groups were 11.8 (20 of 169 patients) and 14.4% (303 of 2102 patients), respectively (p = 0.22). There were no differences in the locoregional and distant recurrences between the two groups. The 5-year disease free survivals for the SSM and mastectomy groups were 81.9 and 81.7%, respectively (p = 0.71). The 5-year overall survivals for the SSM and mastectomy groups were 91.7 and 88,8%, respectively (p = 0.13). In a univariate analysis, the factors associated with a recurrence and the survival rates were the tumor stage and a lymph node positive state. CONCLUSION: No significant differences were found in the recurrence and survival rates of the SSM group, with immediate reconstruction, compared to those of the mastectomy only group. A skin-sparing mastectomy, with immediate reconstruction, which has greater aesthetic benefits, appeared to be an oncologically safe treatment option for breast carcinomas.
Breast Neoplasms ; Chungcheongnam-do ; Follow-Up Studies ; Humans ; Incidence ; Lymph Nodes ; Mastectomy* ; Recurrence* ; Retrospective Studies ; Survival Analysis* ; Survival Rate

PURPOSE: This study evaluated the benefit of radiation therapy in high-risk breast cancer patients who have received immediate transverse rectus abdominis myocutaneous (TRAM) flap reconstruction. The evaluation involved examining the effect of radiation therapy on postmastectomy flap fat necrosis and tumor recurrence. METHODS: A retrospective review was performed on 102 patients who underwent mastectomy and immediate TRAM flap reconstruction between 1996 and 2001 at the Asan Medical Center (Seoul, Korea). The mean patient age was 41 years, and the median follow-up time was 33 months. Skin-sparing mastectomy was con ducted in 82 patients (80.4%) and classical mastectomy in 20 patients (19.6%). Of the 21 high-risk patients needing postmastectomy radiation therapy, nine received it. RESULTS: Moderate or severe TRAM flap fat necrosis occurred more frequently in patients receiving radiation therapy than those not receiving radiation therapy (55.6% vs. 19.4%, P=0.026). In the group with high-risk patients, two tumor recurrences occurred (one-locoregional and one-systemic). Among the 102 patients, thirteen had recurrences, including only two high-risk patients, with almost of them being systemic recurrences except four locoregional recurrences. CONCLUSION: Our findings showed that radiation therapy increased flap fat necrosis in high-risk patients underwent immediate TRAM flap reconstruction. Such necrosis can result in poor outcomes for reconstruction. We recommend careful consideration prior to using radiation therapy on high-risk breast cancer patients after immediate TRAM flap reconstruction, where clinicians need to balance the possible positive effects on recurrence with the possible negative effects on flap tissue.
Breast Neoplasms* ; Breast* ; Chungcheongnam-do ; Fat Necrosis* ; Follow-Up Studies ; Humans ; Mastectomy* ; Necrosis ; Rectus Abdominis ; Recurrence ; Retrospective Studies

BACKGROUND: Liquid nitrogen freezing techniques have already met with widespread success in biology and medicine as a means of long-term storage for cells and tissues. The use of cryoprotectants such as glycerol and dimethylsulphoxide to prevent ice crystal formation, with carefully controlled rates of freezing and thawing, allows both structure and viability to be retained almost indefinitely. Cryopreservation of various tissues has various controlled rates of freezing. MATERIAL AND METHOD: To find the optimal freezing curve and the chamber temperature, we approached the thermodynamic calculation of tissues in two ways. One is the direct calculation method. We should know the thermophysical characteristics of all components, latent heat of fusion, area, density and volume, etc. This kind of calculation is so sophisticated and some variables may not be determined. The other is the indirect calculation method. We performed the tissue freezing with already used freezing curve and we observed the actualfreezing curve of that tissue. And we modified the freezing curve with several steps of calculation, polynomial regression analysis, time constant calculation, thermal response calculation and inverse calculation of chamber temperature. RESULT: We applied that freezing program on mesenchymal stem cell, chondrocyte, and osteoblast. The tissue temperature decreased according to the ideal freezing curve without temperature rising. We did not find any differences in survival. The reason is postulated to be that freezing material is too small and contains cellular components. We expect the significant difference in cellular viability if the freezing curve is applied on a large scale of tissues. CONCLUSION: This program would be helpful in finding the chamber temperature for the ideal freezing curve easily.
Biology ; Chondrocytes ; Cryopreservation ; Dimethyl Sulfoxide ; Freezing* ; Glycerol ; Hot Temperature* ; Ice ; Mesenchymal Stromal Cells ; Nitrogen ; Osteoblasts ; Thermodynamics ; Transplantation, Homologous

BACKGROUND: Hemodynamic derangement during the displacement of the beating heart in off-pump coronary artery bypass graft surgery (OPCAB) might be related with right ventricular (RV) dysfunction. This study evaluated the influence of displacing and stabilizing the heart, for the anastomosis of coronary arteries, on hemodynamic alterations and RV function in patients undergoing OPCAB. METHODS: Twenty patients with triple vessel coronary artery disease underwent OPCAB using single pericardial sutures: a tissue stabilizer was included. The hemodynamic variables and right ventricular ejection fraction (RVEF) were obtained using a right-heart ejection fraction thermodilution pulmonary artery catheter after the induction of anesthesia, before and after anastomosis of each coronary artery and after sternal closure. RESULTS: No significant hemodynamic changes were observed during the displacement of the heart or the placement of a stabilizer on all of the coronary arteries, except the obtuse marginal artery (OM) before anastomosis. RVEF, left ventricular stroke work index (LVSWI), stroke volume index and cardiac index (CI) decreased and mean pulmonary artery pressure increased significantly whist positioning the graft to the OM. Right ventricular volumes were not significantly changed, although central venous pressure and pulmonary capillary wedge pressure increased. Changing CI had a close relationship with LVSWI (r2 = 0.537, P <0.05) but not with RVEF (r2 = 0.118). These hemodynamic compromises recovered to baseline values after sternal closure. CONCLUSIONS: The displacement of the beating heart for positioning during anastomosis of the graft to the OM caused significant hemodynamic instability and LV functional changes in addition to RV functional changes seemed to be responsible for hemodynamic derangements.
Anesthesia ; Arteries ; Catheters ; Central Venous Pressure ; Coronary Artery Bypass, Off-Pump ; Coronary Artery Disease ; Coronary Vessels ; Heart* ; Hemodynamics* ; Humans ; Pulmonary Artery ; Pulmonary Wedge Pressure ; Stroke ; Stroke Volume ; Sutures ; Thermodilution ; Thoracic Surgery* ; Transplants ; Ventricular Function, Right*

PURPOSE: B1 field of birdcage RF (radiofrequency) coil that is used most for brain imaging in magnetic resonance imaging (MRI) decreases toward endring from the coil center. We investigated how much RF B1 homogeneity effect the endcap shield brings form the coil center as it towards to endcap region. MATERIALS AND METHODS: We compared RF B1 field distribution by each finite difference time domain (FDTD) simulations for lowpass, highpass and hybrid birdcage RF coils. We selected the highpass birdcage RF coil that was the highest RF B1 field condition as simulation result, and studied how much RF B1 homogeneity effect was occurred when endcap shield was applied to endring area. RESULTS: B1 field of the highpass birdcage RF coil was higher than other birdcage RF coil types as simulation result. However, the RF B1 homogeneity was lower than other coil types. RF B1 field of highpass birdcage RF coil with endcap shield is similar with RF B1 field of hybrid birdcage RF coil and the overall RF B1 homogeneity in sagittal direction was better. CONCLUSION: In this paper, proposed method can apply improving RF B1 homogeneity of RF coil in clinical examination.
Magnetic Resonance Imaging* ; Neuroimaging

PURPOSES: To investigate the viral etiology of community-acquired pneumonia in Korean adults, we have detected respiratory viruses (Respiatory syncytial virus, adenovirus, influenza virus and parainfluenza virus) in the way of prospective, multi-center study. METHODS: From July 1997 to April 2000, nasal aspirates or sputum were obtained from adults patients with community pneumonia admitted to the participating hospitals and transferred immediately to the central laboratory in the Seoul National University Children's Hospital. The specimens were divided into three parts. One part was used for indirect immunofluorescent test for respiratory viruses, the other part for the culture of RSV and adenovirus in HEp-2 cell monolayer. Another part was used for the culture of influenza virus and parainfluenza virus in MDCK or LLC- MK2 cell monolayers. RESULTS: Of 317 samples, 32 (10.1%) specimens were positive for viral isolation by indirect IF staining or culture, including one dual-infected specimen (adenovirus and parainfluenza virus). Influenza virus was most commonly detected (16 specimens). Parainfluenza virus, adenovirus and RSV were detected in 10, 4 and 3 patients, respectively. All isolated influenza viruses were type A (H3N2 in 9 patients, H1N1 in 2 and unspecified in 5), and 8 out of 10 parainfluenza virus isolates were type 3. CONCLUSION: Similar to previous foreign reports, a significant portion of community-acquired pneumonia in Korean adult is caused by respiratory viruses. Our data empathized the need of referral system for viral diagnosis and of nationwide investigation on respiratory virus infections.
Adenoviridae ; Adult* ; Diagnosis ; Humans ; Orthomyxoviridae ; Paramyxoviridae Infections ; Pneumonia* ; Prospective Studies ; Referral and Consultation ; Seoul ; Sputum