• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2334-2340
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• 2021

Radioactive particle tracking (RPT) is a minimally invasive nuclear technique that tracks a radioactive particle inside a volume of interest by means of a mathematical location algorithm. During the past decades, many algorithms have been developed including ones based on artificial intelligence techniques. In this study, RPT technique is applied in a simulated test section that employs a simplified mixer filled with concrete, six scintillator detectors and a¹³⁷Cs radioactive particle emitting gamma rays of 662 keV. The test section was developed using MCNPX code, which is a mathematical code based on Monte Carlo simulation, and 3516 different radioactive particle positions (x,y,z) were simulated. Novelty of this paper is the use of a location algorithm based on a deep learning model, more specifically a 6-layers deep rectifier neural network (DRNN), in which hyperparameters were defined using a Bayesian optimization method. DRNN is a type of deep feedforward neural network that substitutes the usual sigmoid based activation functions, traditionally used in vanilla Multilayer Perceptron Networks, for rectified activation functions. Results show the great accuracy of the DRNN in a RPT tracking system. Root mean squared error for x, y and coordinates of the radioactive particle is, respectively, 0.03064, 0.02523 and 0.07653.

• Journal of the Korean Orthopaedic Association
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• v.56 no.4
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• pp.361-365
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• 2021

Pelvic fractures are high-energy injuries, often accompanied by damage to the adjacent tissues and organs. For patients with pelvic trauma, active treatment is required early in the injury, because mortality can increase if appropriate treatment is not provided. In most cases, however, minimally invasive surgery is considered because extensive surgery cannot be performed due to the patient's condition. Percutaneous fixation of the pubis has been introduced because it can be applied easily to achieve the stability of the anterior part of the pelvis. Although many studies introduced percutaneous fixation of pubic bone fractures, most describe screw fixation for nondisplaced fractures. When treating displaced fractures with percutaneous screw fixation, it is difficult for the guide pin or drill bit to avoid the joint surface. Using a bent guide pin could allow easy insertion of the cannulated screw while avoiding the articular surface.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.1
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• pp.73-79
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• 2022

Purpose : Kinesio taping applied to the ankle varies, and if the overall ankle is taped as much as possible, several effects, including balance, can be expected, but clinically the cost reduction for intervention is very important. Therefore, this study attempted to find out the optimal way to the effect and cost of kinesio taping on ankle dynamic balance. Methods : The subject of this study was 24 university students in their 20s (male: 13, female: 11), who received sufficient explanation of the purpose and method of the study. The Cumberland ankle instability tool (CAIT) questionnaire was used for the degree of ankle instability of the study subjects. If the subject's CAIT score was 28 points or more, it was classified as a stable ankle, and if the score was 24 points or less, it was classified as functional ankle instability (FAI). In this study, Biodex Balance System^® measurement equipment was used to calculate the dynamic balance of study participants. The application of kinesio taping was performed by one physical therapist to attach in the same way, and a method of wrapping the ankle joint was applied in the eight-shaped bandage. Results : The results are as follows in before and after taping of the stable ankle and FAI group. There was no significant difference in the overall, anterior-posterior, and medial-lateral stability index. The comparison is as follows between groups for the differences (post-pre value) in before and after the application of kinesio taping. There were no significant differences between groups in all the overall, anterior-posterior, and medial-lateral stability index. Conclusion : In this study, no significant difference in kinesio taping was found in the dynamic balance of stable ankle and FAI (overall, anterior-posterior, and medial-lateral). It is necessary to continue to study ways to find the maximum effect while minimally attaching them to the application method of ankle kinesio taping.

• Journal of Chest Surgery
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• v.56 no.1
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• pp.42-48
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• 2023

Background: With recent advances in cardiac surgery through minimal access, mini-thoracotomy has emerged as an excellent alternative for cardiac myxoma resection. This study analyzed the surgical results of this approach, focusing on postoperative cerebral embolism and tumor recurrence. Methods: We retrospectively reviewed 64 patients (mean age, 56.0±12.1 years; 40 women) who underwent myxoma resection through mini-thoracotomy from October 2008 to July 2020. We conducted femoral cannulation and antegrade cardioplegic arrest in all patients. Patient characteristics and perioperative data, including brain diffusion-weighted magnetic resonance imaging (DWI) findings, were collected. Medium-term echocardiographic follow-up was performed. Results: Thirteen patients (20.3%) had a history of preoperative stroke, and 7 (11.7%) had dyspnea with New York Heart Association functional class III or IV. Sixty-one cases (95.3%) had myxomas in the left atrium. The mean cardiopulmonary bypass and cardiac ischemic times were 69.0±28.6 and 34.1±15.0 minutes, respectively. Sternotomy conversion was not performed in any case, and 50 patients (78.1%) were extubated in the operating room. No early mortality or postoperative clinical stroke occurred. Postoperative DWI was performed in 32 (53%) patients, and 7 (22%) showed silent cerebral embolisms. One patient underwent reoperation for tumor recurrence during the study period; in that patient, a genetic study confirmed the Carney complex. Conclusion: Mini-thoracotomy for cardiac myxoma resection showed acceptable clinical and neurological outcomes. In the medium-term echocardiographic follow-up, reliable resection was proven, with few recurrences. This approach is a promising alternative for cardiac myxoma resection.

• Korean Journal of Clinical Pharmacy
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• v.33 no.3
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• pp.195-201
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• 2023

Background: Hematocrit is usually measured from venous blood collected by invasive venipuncture. This study was performed to determine hematocrit accurately and precisely using minimally invasive volumetric absorptive microsampling (VAMS) technique. Such technique is to be applied to determining hematocrit in various clinical settings for the care, including therapeutic drug monitoring, of neonatal or epileptic patients, or patients with high risk of infection or bleeding. Methods: The study was performed using 31 VAMS samples obtained from 21 pancreatic cancer patients. Hematocrit was determined using the values of potassium concentrations obtained from blood in VAMS tips (Hct_VAMS). Hct_VAMS was compared with hematocrit measured from blood collected by venipuncture (Hct_VP). The accuracy and precision of Hct_VAMS in comparison to Hct_VP were evaluated using Bland-Altman plot, Deming regression and mountain plot. Results: Bland-Altman plot displayed a random scattering pattern of the differences between Hct_VAMS and Hct_VP with the mean bias of -0.010 and the 95% limit of agreement ranging from -0.063 to 0.044. Deming regression for Hct_VAMS and Hct_VP line demonstrated very small proportional and constant biases of 1.04 and -0.003, respectively. Mountain plot exhibited a narrow and symmetrical distribution of the differences with their median of -0.011 and central 95% range from -0.049 to 0.033. Conclusion: Hematocrit was accurately and precisely determined using less invasive VAMS technique. Such technique appears to be applicable to determining hematocrit in situations that venipuncture is not favorable or possible.

• Journal of Korean Neurosurgical Society
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• v.66 no.4
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• pp.426-437
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• 2023

Objective : To investigate the efficacy and safety of the posterior endoscopic cervical foraminotomy (PECF) using ultrasonic osteotome for the treatment of cervical osseous foraminal stenosis, focusing on introduction of the advantages of ultrasonic osteotome in partial pediculectomy and ventral osteophyte resection in PECF. Methods : Nineteen patients with cervical osseous foraminal stenosis who underwent PECF using ultrasonic osteotome in our institution between April 2018 and April 2021 were enrolled in this study. All the patients were followed up more than 12 months. The patients' medical data, as well as pre- and postoperative radiologic findings were thoroughly investigated. The visual analogue score (VAS), Japanese Orthopaedic Association (JOA) score, cervical dysfunction index (Neck disability index, NDI), and modified MacNab criteria were used to assess the surgical efficacy. Results : All the patients were successfully treated with PECF using ultrasonic osteotome. The pre- and postoperative VAS, NDI, and JOA scores were significantly improved (p<0.05). According to the modified MacNab criteria, 17 patients were assessed as "excellent", two patients were assessed as "good" at the last follow-up. There was no dura tear, nerve root damage, incision infection, neck deformity, or other complications. Conclusion : Adequate nerve root decompression can be accomplished successfully with the help of ultrasonic osteotome in PECF, which has the advantage of reducing the probability of damage to the nerve root and dura mater, in addition to the original merits of endoscopic surgery.

• Journal of Chest Surgery
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• v.56 no.4
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• pp.229-237
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• 2023

Background: We aimed to demonstrate the advances we have achieved in pectus excavatum surgery over the last 10 years, with a particular focus on the refinement of pectus bar stabilization techniques and devices. Methods: In total, 1,526 patients who underwent minimally invasive repair of pectus excavatum surgery from 2013 to 2022 were enrolled and analyzed. We have pursued a new paradigm of crane-powered remodeling of the entire chest wall. The method of bar stabilization has changed from claw fixators to hinge plates and, finally, to bridge plate connections. We also evaluated the effectiveness of the hinge plate (group H) and the bridge plate (group B). Results: The bar displacement rates were 0.1% (n=2) for the claw fixator, 0% for the hinge plate (n=0), and 0% for the bridge plate (n=0). We stopped using the claw fixator in 2022 and the hinge plate in 2019. Since 2022, when we shifted to a multiple-bar technique for all patients, the bridge plate has replaced both the claw fixator and the hinge plate. No bar displacement occurred in either group. Group H had more pleural effusion, wound problems (p<0.05), and longer stays (5.5 vs. 6.2 days, p=0.034) than group B. Conclusion: We have made significant progress in pectus repair surgery over the last decade, particularly in stabilizing the pectus bar and reducing perioperative complications. Our current strategy is the multiple-bar approach with bridge stabilization. Since the bridge-only technique resulted in no bar displacement, we could eliminate the invasive claw fixator or hinge plate.

• Journal of Gastric Cancer
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• v.23 no.3
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• pp.487-498
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• 2023

Purpose: Reduced port surgery (RPS) for gastric cancer has been frequently reported in distal gastrectomies but rarely in total gastrectomies. This study aimed to determine the feasibility of 3-port totally laparoscopic total gastrectomy (TLTG) with overlapping esophagojejunal (EJ) anastomosis. Materials and Methods: A total of 81 patients who underwent curative TLTG for gastric cancer (36 and 45 patients with 3-port and 5-port TLTG, respectively) were evaluated. All 3-port TLTG procedures were performed with the same method as 5-port TLTG, including EJ anastomosis with the intracorporeal overlap method using a linear stapler, except for the number of ports and assistants. Short-term outcomes, including the number of lymph nodes (LNs) harvested by station and postoperative complications, were analyzed retrospectively. Results: Clinical characteristics were not significantly different among the groups, except that the 3-port TLTG group was younger and had a lower rate of pulmonary comorbidity. There were no cases of open conversion or additional port placement. All operative details and the number of harvested LNs did not differ between the groups, but the rate of suprapancreatic LN harvest was higher in the 3-port TLTG group. No significant differences were observed in the overall complication rates between the 2 groups. Conclusions: Three-port TLTG with overlapping EJ anastomoses using a linear stapler is a feasible RPS procedure for total gastrectomy to treat gastric cancer.

• Journal of Chest Surgery
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• v.56 no.2
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• pp.90-98
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• 2023

Background: Atrial fibrillation (AF) is the most common type of cardiac arrhythmia. Totally thoracoscopic ablation (TTA) is a surgical treatment showing a high success rate as a hybrid procedure with radiofrequency catheter ablation to control AF. This study compared the early complications of warfarin and non-vitamin K antagonist oral anticoagulants (NOACs) in patients who underwent TTA. Methods: This single-center retrospective cohort study enrolled patients who underwent planned TTA for AF from February 2012 to October 2020. All patients received postoperative anticoagulation, either with warfarin or a NOAC (apixaban, rivaroxaban, dabigatran, or edoxaban). Propensity score matching was performed for both groups. Early complications were assessed at 12 weeks after TTA and were divided into efficacy and safety outcomes. Both efficacy and safety outcomes were compared in the propensity score-matched groups. Results: Early complications involving efficacy outcomes, such as stroke and transient ischemic attack, were seen in 5 patients in the warfarin group and none in the NOAC group. Although the 2 groups differed in the incidence of efficacy outcomes, it was not statistically significant. In safety outcomes, 11 patients in the warfarin group and 24 patients in the NOAC group had complications, but likewise, the between-group difference was not statistically significant. Conclusion: Among patients who underwent TTA, those who received NOACs had a lower incidence of thromboembolic complications than those who received warfarin; however, both groups showed a similar bleeding complication rate. Using a NOAC after TTA does not reduce efficacy and safety when compared to warfarin.

• Journal of Digestive Cancer Research
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• v.5 no.1
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• pp.23-27
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• 2017

Although laparoscopic pancreaticoduodenectomy (LPD) is considered as minimally invasive surgery, an advanced level of laparoscopic skill is still required. LPD comprises various procedures including reconstruction. Therefore, establishment of a safe approach at each step is needed. Prevention of intraoperative bleeding is the most important factor in safe completion of LPD. The establishment of effective retraction methods is also important at each site to prevent vascular injury. I also recommend the "uncinate process first" approach during initial cases of LPD, in which the branches of the inferior pancreaticoduodenal artery are dissected first, at points where they enter the uncinate process. This approach is performed at the left side of the superior mesenteric artery (SMA) before isolating the pancreatic head from the right aspect of the SMA, which allows safe dissection without bleeding. Safe and reliable reconstruction is also important to prevent postoperative complications. Laparoscopic pancreatojejunostomy requires highly skilled suturing technique. Pancreatojejunostomy through a small abdominal incision, as in hybrid-LPD, facilitates reconstruction. In LPD, the surgical view is limited. Therefore, we must carefully verify the position of the pancreaticobiliary limb. A twisted mesentery may cause severe congestion of the pancreaticobiliary limb following reconstruction, resulting in severe complications. We must secure the appropriate position of the pancreaticobiliary limb before starting reconstruction. We describe the incidence of intraoperative and postoperative complications and appropriate technique for safe performance of LPD.