1.Development of colonic stent simulator using three-dimensional printing technique: a simulator development study in Korea
Hyundam GU ; Suyoung LEE ; Sol KIM ; Hye-Lim JANG ; Da-Woon CHOI ; Kyu Seok KIM ; Yu Ri SHIN ; Dae Young CHEUNG ; Bo-In LEE ; Jin Il KIM ; Han Hee LEE
Clinical Endoscopy 2024;57(6):790-797
Background/Aims:
Colonic stenting plays a vital role in the management of acute malignant colonic obstruction. The increasing use of self-expandable metal stents (SEMS) and the diverse challenges posed by colonic obstruction at various locations underscore the importance of effective training for colonic stent placement.
Methods:
All the components of the simulator were manufactured using silicone molding techniques in conjunction with three-dimensional (3D) printing. 3D images sourced from computed tomography scans and colonoscopy images were converted into a stereolithography format. Acrylonitrile butadiene styrene copolymers have been used in fused deposition modeling to produce moldings.
Results:
The simulator replicated the large intestine from the rectum to the cecum, mimicking the texture and shape of the human colon. It enables training for colonoscopy insertion, cecum intubation, loop reduction, and stenting within stenotic areas. Interchangeable stenotic modules for four sites (rectum, sigmoid colon, descending colon, and ascending colon) were easily assembled for training. These modules integrate tumor contours and blood vessel structures with a translucent center, allowing real-time visualization during stenting. Successful and repeatable demonstrations of stent insertion and expansion using the reusable SEMS were consistently achieved.
Conclusions
This innovative simulator offers a secure colonic stenting practice across various locations, potentially enhancing clinical outcomes by improving operator proficiency during actual procedures.
2.Development of colonic stent simulator using three-dimensional printing technique: a simulator development study in Korea
Hyundam GU ; Suyoung LEE ; Sol KIM ; Hye-Lim JANG ; Da-Woon CHOI ; Kyu Seok KIM ; Yu Ri SHIN ; Dae Young CHEUNG ; Bo-In LEE ; Jin Il KIM ; Han Hee LEE
Clinical Endoscopy 2024;57(6):790-797
Background/Aims:
Colonic stenting plays a vital role in the management of acute malignant colonic obstruction. The increasing use of self-expandable metal stents (SEMS) and the diverse challenges posed by colonic obstruction at various locations underscore the importance of effective training for colonic stent placement.
Methods:
All the components of the simulator were manufactured using silicone molding techniques in conjunction with three-dimensional (3D) printing. 3D images sourced from computed tomography scans and colonoscopy images were converted into a stereolithography format. Acrylonitrile butadiene styrene copolymers have been used in fused deposition modeling to produce moldings.
Results:
The simulator replicated the large intestine from the rectum to the cecum, mimicking the texture and shape of the human colon. It enables training for colonoscopy insertion, cecum intubation, loop reduction, and stenting within stenotic areas. Interchangeable stenotic modules for four sites (rectum, sigmoid colon, descending colon, and ascending colon) were easily assembled for training. These modules integrate tumor contours and blood vessel structures with a translucent center, allowing real-time visualization during stenting. Successful and repeatable demonstrations of stent insertion and expansion using the reusable SEMS were consistently achieved.
Conclusions
This innovative simulator offers a secure colonic stenting practice across various locations, potentially enhancing clinical outcomes by improving operator proficiency during actual procedures.
3.Development of colonic stent simulator using three-dimensional printing technique: a simulator development study in Korea
Hyundam GU ; Suyoung LEE ; Sol KIM ; Hye-Lim JANG ; Da-Woon CHOI ; Kyu Seok KIM ; Yu Ri SHIN ; Dae Young CHEUNG ; Bo-In LEE ; Jin Il KIM ; Han Hee LEE
Clinical Endoscopy 2024;57(6):790-797
Background/Aims:
Colonic stenting plays a vital role in the management of acute malignant colonic obstruction. The increasing use of self-expandable metal stents (SEMS) and the diverse challenges posed by colonic obstruction at various locations underscore the importance of effective training for colonic stent placement.
Methods:
All the components of the simulator were manufactured using silicone molding techniques in conjunction with three-dimensional (3D) printing. 3D images sourced from computed tomography scans and colonoscopy images were converted into a stereolithography format. Acrylonitrile butadiene styrene copolymers have been used in fused deposition modeling to produce moldings.
Results:
The simulator replicated the large intestine from the rectum to the cecum, mimicking the texture and shape of the human colon. It enables training for colonoscopy insertion, cecum intubation, loop reduction, and stenting within stenotic areas. Interchangeable stenotic modules for four sites (rectum, sigmoid colon, descending colon, and ascending colon) were easily assembled for training. These modules integrate tumor contours and blood vessel structures with a translucent center, allowing real-time visualization during stenting. Successful and repeatable demonstrations of stent insertion and expansion using the reusable SEMS were consistently achieved.
Conclusions
This innovative simulator offers a secure colonic stenting practice across various locations, potentially enhancing clinical outcomes by improving operator proficiency during actual procedures.
4.Efficacy and Safety of Metformin and Atorvastatin Combination Therapy vs. Monotherapy with Either Drug in Type 2 Diabetes Mellitus and Dyslipidemia Patients (ATOMIC): Double-Blinded Randomized Controlled Trial
Jie-Eun LEE ; Seung Hee YU ; Sung Rae KIM ; Kyu Jeung AHN ; Kee-Ho SONG ; In-Kyu LEE ; Ho-Sang SHON ; In Joo KIM ; Soo LIM ; Doo-Man KIM ; Choon Hee CHUNG ; Won-Young LEE ; Soon Hee LEE ; Dong Joon KIM ; Sung-Rae CHO ; Chang Hee JUNG ; Hyun Jeong JEON ; Seung-Hwan LEE ; Keun-Young PARK ; Sang Youl RHEE ; Sin Gon KIM ; Seok O PARK ; Dae Jung KIM ; Byung Joon KIM ; Sang Ah LEE ; Yong-Hyun KIM ; Kyung-Soo KIM ; Ji A SEO ; Il Seong NAM-GOONG ; Chang Won LEE ; Duk Kyu KIM ; Sang Wook KIM ; Chung Gu CHO ; Jung Han KIM ; Yeo-Joo KIM ; Jae-Myung YOO ; Kyung Wan MIN ; Moon-Kyu LEE
Diabetes & Metabolism Journal 2024;48(4):730-739
Background:
It is well known that a large number of patients with diabetes also have dyslipidemia, which significantly increases the risk of cardiovascular disease (CVD). This study aimed to evaluate the efficacy and safety of combination drugs consisting of metformin and atorvastatin, widely used as therapeutic agents for diabetes and dyslipidemia.
Methods:
This randomized, double-blind, placebo-controlled, parallel-group and phase III multicenter study included adults with glycosylated hemoglobin (HbA1c) levels >7.0% and <10.0%, low-density lipoprotein cholesterol (LDL-C) >100 and <250 mg/dL. One hundred eighty-five eligible subjects were randomized to the combination group (metformin+atorvastatin), metformin group (metformin+atorvastatin placebo), and atorvastatin group (atorvastatin+metformin placebo). The primary efficacy endpoints were the percent changes in HbA1c and LDL-C levels from baseline at the end of the treatment.
Results:
After 16 weeks of treatment compared to baseline, HbA1c showed a significant difference of 0.94% compared to the atorvastatin group in the combination group (0.35% vs. −0.58%, respectively; P<0.0001), whereas the proportion of patients with increased HbA1c was also 62% and 15%, respectively, showing a significant difference (P<0.001). The combination group also showed a significant decrease in LDL-C levels compared to the metformin group (−55.20% vs. −7.69%, P<0.001) without previously unknown adverse drug events.
Conclusion
The addition of atorvastatin to metformin improved HbA1c and LDL-C levels to a significant extent compared to metformin or atorvastatin alone in diabetes and dyslipidemia patients. This study also suggested metformin’s preventive effect on the glucose-elevating potential of atorvastatin in patients with type 2 diabetes mellitus and dyslipidemia, insufficiently controlled with exercise and diet. Metformin and atorvastatin combination might be an effective treatment in reducing the CVD risk in patients with both diabetes and dyslipidemia because of its lowering effect on LDL-C and glucose.
5.Effects of rhBMP‑2 with various carriers on maxillofacial bone regeneration through computed tomography evaluation
Ja In SEO ; Ji Hye LIM ; Woo Min JO ; Jeong Keun LEE ; Seung Il SONG
Maxillofacial Plastic and Reconstructive Surgery 2023;45(1):40-
Background:
rhBMP-2 is regarded as the most potent osteoinductive growth factor, and it has been used in the oral cavity with different carriers. The purpose of this study is to evaluate the bone-regenerative effect of rhBMP-2 delivered with different carrier systems through three-dimensional cone beam computed tomography analysis.Method A total of 112 patients underwent oral surgery with rhBMP-2 application (Group 1, n = 53) or without rhBMP-2 application (Group 2, n = 59). Group 1 was divided into 3 groups according to carriers, rhBMP-2 with allograft (Group 1–1, n = 34), rhBMP-2 with xenograft (Group 1–2, n = 5), and rhBMP-2 with absorbable collagen sponge (Group 1–3, n = 14). Cone beam computed tomography scans were taken before surgery (T0) 6 months after surgery (T1). The volume of defects was measured through the three-dimensional image analysis tool.
Results:
The average bone regeneration rate of Group 1 was significantly greater than that of Group 2. Within Group 1, the group that used allograft as a carrier (Group 1–1) showed significantly higher bone regeneration rates than the group that used absorbable collagen sponge as a carrier (Group 1–3).
Conclusion
The use of rhBMP-2 after oral surgery results in a superior bone regeneration rate compared to not using rhBMP-2, and its efficacy depends on the carriers it is used with. Allograft affects bone regeneration more than absorbable collagen sponge when it is carried with rhBMP-2. Therefore, the appropriate use of rhBMP-2 with suitable bone grafting materials is useful for promoting postoperative bone regeneration in oral surgery.
6.The Korean Society for Neuro-Oncology (KSNO) Guideline for the Management of Brain Tumor Patients During the Crisis Period: A Consensus Survey About Specific Clinical Scenarios (Version 2023.1)
Min-Sung KIM ; Se-Il GO ; Chan Woo WEE ; Min Ho LEE ; Seok-Gu KANG ; Kyeong-O GO ; Sae Min KWON ; Woohyun KIM ; Yun-Sik DHO ; Sung-Hye PARK ; Youngbeom SEO ; Sang Woo SONG ; Stephen AHN ; Hyuk-Jin OH ; Hong In YOON ; Sea-Won LEE ; Joo Ho LEE ; Kyung Rae CHO ; Jung Won CHOI ; Je Beom HONG ; Kihwan HWANG ; Chul-Kee PARK ; Do Hoon LIM ;
Brain Tumor Research and Treatment 2023;11(2):133-139
Background:
During the coronavirus disease 2019 (COVID-19) pandemic, there was a shortage of medical resources and the need for proper treatment guidelines for brain tumor patients became more pressing. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, has undertaken efforts to develop a guideline that is tailored to the domestic situation and that can be used in similar crisis situations in the future. As part II of the guideline, this consensus survey is to suggest management options in specific clinical scenarios during the crisis period.
Methods:
The KSNO Guideline Working Group consisted of 22 multidisciplinary experts on neuro-oncology in Korea. In order to confirm a consensus reached by the experts, opinions on 5 specific clinical scenarios about the management of brain tumor patients during the crisis period were devised and asked. To build-up the consensus process, Delphi method was employed.
Results:
The summary of the final consensus from each scenario are as follows. For patients with newly diagnosed astrocytoma with isocitrate dehydrogenase (IDH)-mutant and oligodendroglioma with IDH-mutant/1p19q codeleted, observation was preferred for patients with low-risk, World Health Organization (WHO) grade 2, and Karnofsky Performance Scale (KPS) ≥60, while adjuvant radiotherapy alone was preferred for patients with high-risk, WHO grade 2, and KPS ≥60. For newly diagnosed patients with glioblastoma, the most preferred adjuvant treatment strategy after surgery was radiotherapy plus temozolomide except for patients aged ≥70 years with KPS of 60 and unmethylated MGMT promoters. In patients with symptomatic brain metastasis, the preferred treatment differed according to the number of brain metastasis and performance status. For patients with newly diagnosed atypical meningioma, adjuvant radiation was deferred in patients with older age, poor performance status, complete resection, or low mitotic count.
Conclusion
It is imperative that proper medical care for brain tumor patients be sustained and provided, even during the crisis period. The findings of this consensus survey will be a useful reference in determining appropriate treatment options for brain tumor patients in the specific clinical scenarios covered by the survey during the future crisis.
7.The Korean Society for Neuro-Oncology (KSNO) Guideline for the Management of Brain Tumor Patients During the Crisis Period: A Consensus Recommendation Using the Delphi Method (Version 2023.1)
Min-Sung KIM ; Se-Il GO ; Chan Woo WEE ; Min Ho LEE ; Seok-Gu KANG ; Kyeong-O GO ; Sae Min KWON ; Woohyun KIM ; Yun-Sik DHO ; Sung-Hye PARK ; Youngbeom SEO ; Sang Woo SONG ; Stephen AHN ; Hyuk-Jin OH ; Hong In YOON ; Sea-Won LEE ; Joo Ho LEE ; Kyung Rae CHO ; Jung Won CHOI ; Je Beom HONG ; Kihwan HWANG ; Chul-Kee PARK ; Do Hoon LIM ;
Brain Tumor Research and Treatment 2023;11(2):123-132
Background:
During the coronavirus disease 2019 (COVID-19) pandemic, the need for appropriate treatment guidelines for patients with brain tumors was indispensable due to the lack and limitations of medical resources. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, has undertaken efforts to develop a guideline that is tailored to the domestic situation and that can be used in similar crisis situations in the future.
Methods:
The KSNO Guideline Working Group was composed of 22 multidisciplinary experts on neuro-oncology in Korea. In order to reach consensus among the experts, the Delphi method was used to build up the final recommendations.
Results:
All participating experts completed the series of surveys, and the results of final survey were used to draft the current consensus recommendations. Priority levels of surgery and radiotherapy during crises were proposed using appropriate time window-based criteria for management outcome. The highest priority for surgery is assigned to patients who are life-threatening or have a risk of significant impact on a patient’s prognosis unless immediate intervention is given within 24–48 hours. As for the radiotherapy, patients who are at risk of compromising their overall survival or neurological status within 4–6 weeks are assigned to the highest priority. Curative-intent chemotherapy has the highest priority, followed by neoadjuvant/adjuvant and palliative chemotherapy during a crisis period. Telemedicine should be actively considered as a management tool for brain tumor patients during the mass infection crises such as the COVID-19 pandemic.
Conclusion
It is crucial that adequate medical care for patients with brain tumors is maintained and provided, even during times of crisis. This guideline will serve as a valuable resource, assisting in the delivery of treatment to brain tumor patients in the event of any future crisis.
8.Can clinicopathologic high-risk features in T3N0 colon cancer be reliable prognostic factors?
Hyun Gu LEE ; Young IL KIM ; In Ja PARK ; Seok-Byung LIM ; Chang Sik YU
Annals of Surgical Treatment and Research 2023;104(2):109-118
Purpose:
The purpose of this study was to assess the reliability and prognostic significance of the high-risk feature (HRF) in patients with T3N0 colon cancer.
Methods:
We included 1,205 patients with pT3N0 colon cancer treated with curative radical resection between 2012 and 2016. HRF was defined as lymphovascular invasion, perineural invasion, poorly/undifferentiated histology, margin involvement, and preoperative obstruction. We investigated the relationships between the number and type of HRF and recurrence-free survival (RFS) and overall survival (OS), as well as the effect of adjuvant treatment.
Results:
A total of 751 of the patients (62.3%) had more than 1 HRF and 515 of the patients (42.7%) underwent adjuvant treatment. Patients who had more than 2 HRFs had a significantly worse 5-year RFS and OS compared to patients who had neither HRF nor even one HRF. According to the findings of the multivariate analysis, the presence of multiple HRFs was a risk factor for a lower RFS and OS. When the quantity and type of HRF were taken into consideration in the multivariate analysis, adjuvant chemotherapy was not found to be linked with RFS or OS in patients with pT3N0 colon cancer.
Conclusion
In the present study, adjuvant treatment based on the current guideline of treatment indication was unable to enhance the prognosis of patients with pT3N0 colon cancer. The role of adjuvant treatment in T3N0 colon cancer must be examined with the HRF count in mind.
9.Surface-Modifying Effect of Zwitterionic Polyurethane Oligomers Complexed with Metal Ions on Blood Compatibility
Dong-Heon GA ; Chung-Man LIM ; Yoonsun JANG ; Tae Il SON ; Dong Keun HAN ; Yoon Ki JOUNG
Tissue Engineering and Regenerative Medicine 2022;19(1):35-47
BACKGROUND:
To prevent unsolved problems of medical devices, we hypothesized that combinatorial effects of zwitterionic functional group and anti-bacterial metal ions can reduce effectively the thrombosis and bacterial infection of polymeric biomaterials. In this research, we designed a novel series of zwitterionic polyurethane (zPU) additives to impart anti-thrombotic properties to a polyvinyl chloride (PVC) matrix.
METHODS:
We have synthesized zPUs by combination of various components and zPUs complexed with metal ions. Zwitterion group was prepared by reaction with 1,3-propane sultone and Nmethyldiethanolamine and metal ions were incorporated into sulfobetaine chains via molecular complexation. These zPU additives were characterized using FT-IR, 1H-NMR, elemental analysis, and thermal analysis. The PVC film blended with zPU additives were prepared by utilizing a solvent casting and hot melting process.
RESULTS:
Water contact angle demonstrated that the introduction of zwitterion group has improved hydrophilicity of polyurethanes dramatically. Protein adsorption test resulted in improved anti-fouling effects dependent on additive concentration and decreases in their effects by metal complexation. Platelet adhesion test revealed anti-fouling effects by additive blending but not significant as compared to protein resistance results.
CONCLUSION
With further studies, the synthesized zPUs and zPUs complexed with metal ions are expected to be used as good biomaterials in biomedical fields. Based on our results, we can carefully estimate that the enhanced anti-fouling effect contributed to reduced platelet adhesion.
10.The Antibiotic-Vaseline Soaked Cotton Pledget as an Adjuvant Material for Endoscopic Endonasal Fungal Ball Removal
Young Yoon KIM ; Hyung Chae YANG ; Jae Gu KIM ; Hee Young KIM ; Jong Min PARK ; Kwang Il NAM ; Min-Keun SONG ; Sang Chul LIM
Journal of Rhinology 2020;27(1):21-27
Background and Objectives:
Treatment choice for fungal ball is endoscopic endonasal removal. However, it is not easy to remove fungal elements from the maxilla using only an endonasal approach. To overcome this difficulty, we introduced a cotton pledget technique and evaluated its efficacy through a cadaveric study and clinical research.Materials and Method: A cadaveric study was performed using 10 half heads of seven cadavers. The ease and safety of the cotton pledget technique were compared to those of a previously reported technique. In clinical research, we enrolled 52 patients who underwent surgery with the cotton pledget technique and 36 patients who underwent surgery using the conventional endoscopic approach. Demographic factors, preoperative Lund-Mackay (LM) score, sinonasal outcome test (SNOT) score, surgical morbidity, and incomplete removal rate were analyzed.
Results:
The cadaveric study showed that the cotton pledget technique was easier (p=0.011) than the conventional technique. In addition, clinical evaluation showed that the cotton pledget group had significantly lower incomplete removal rate than that of the control group (p=0.010).
Conclusion
The cotton pledget technique is an easy and safe method that enables fungal ball removal more effectively than the conventional technique without need for inferior meatal antrostomy (IMA) or the Caldwell-Luc (CL) approach.

Result Analysis
Print
Save
E-mail