1.Periampullary cancer and whipple's operation.
Ja Yun KOO ; Woo Jung LEE ; Sung Hoon NO ; Myung Wook KIM ; Byung Ro KIM ; Jin Sik MIN ; Kyung Sik LEE
Journal of the Korean Surgical Society 1992;43(4):518-528
No abstract available.
2.Evaluation of an Experimentally Designed Stereotactic Guidance System for Determining Needle Entry Point during Uniplanar Fluoroscopy-guided Intervention.
Jae Heon LEE ; Gye Rok JEON ; Jung Hoon RO ; Gyeong Jo BYOEN ; Tae Kyun KIM ; Kyung Hoon KIM
The Korean Journal of Pain 2012;25(2):81-88
BACKGROUND: In discography performed during percutaneous endoscopic lumbar discectomy (PELD) via the posterolateral approach, it is difficult to create a fluoroscopic tunnel view because a long needle is required for discography and the guide-wire used for consecutive PELD interrupts rotation of fluoroscope. A stereotactic system was designed to facilitate the determination of the needle entry point, and the feasibility of this system was evaluated during interventional spine procedures. METHODS: A newly designed stereotactic guidance system underwent a field test application for PELD. Sixty patients who underwent single-level PELD at L4-L5 were randomly divided into conventional or stereotactic groups. PELD was performed via the posterolateral approach using the entry point on the skin determined by premeasured distance from the midline and angles according to preoperative magnetic resonance imaging (MRI) findings. Needle entry accuracy provided by the two groups was determined by comparing the distance and angle measured by postoperative computed tomography with those measured by preoperative MRI. The duration and radiation exposure for determining the entry point were measured in the groups. RESULTS: The new stereotactic guidance system and the conventional method provided similarly accurate entry points for discography and consecutive PELD. However, the new stereotactic guidance system lowered the duration and radiation exposure for determining the entry point. CONCLUSIONS: The new stereotactic guidance system under fluoroscopy provided a reliable needle entry point for discography and consecutive PELD. Furthermore, it reduced the duration and radiation exposure associated with determining needle entry.
Diskectomy
;
Diskectomy, Percutaneous
;
Equipment Design
;
Fluoroscopy
;
Humans
;
Magnetic Resonance Imaging
;
Needles
;
Skin
;
Spine
;
Stereotaxic Techniques
3.Effect of 457 nm light on the polymerization of dental composite resins
Jung Hoon RO ; Dong Ho YI ; Hyo Joung SEOL ; Yong Hoon KWON
Korean Journal of Dental Materials 2018;45(3):179-186
The aim of this study was to determine if a 457 nm blue laser could effectively polymerize dental composite resins. After light curing 6 dental composite resins using a laser or a LED light-curing unit at 530 mW/cm2 and 900 mW/cm2, respectively, degree of conversion and microhardness were evaluated. Degree of conversion of specimens by the laser and LED was similar (on top surface 54.4–67.7% and 55.2–67.1%, respectively; on bottom surface 35.1–53.8% and 45.4–53.1%, respectively). Microhardness was also similar (on top surface 28.5–83.6 Hv and 19.1–82.4 Hv, respectively; on bottom surface 22.5–65.4 Hv and 16.8–74.4 Hv, respectively), although, in some cases, laser-treated specimens showed slightly lower microhardness than the LED-treated on bottom surface. The present study shows that the 457 nm laser can polymerize dental composite resins to the same level as LED achieved.
Composite Resins
;
Polymerization
;
Polymers
4.Application of Deep Learning System into the Development of Communication Device for Quadriplegic Patient
Jung Hwan LEE ; Taewoo KANG ; Byung Kwan CHOI ; In Ho HAN ; Byung Chul KIM ; Jung Hoon RO
Korean Journal of Neurotrauma 2019;15(2):88-94
OBJECTIVE: In general, quadriplegic patients use their voices to call the caregiver. However, severe quadriplegic patients are in a state of tracheostomy, and cannot generate a voice. These patients require other communication tools to call caregivers. Recently, monitoring of eye status using artificial intelligence (AI) has been widely used in various fields. We made eye status monitoring system using deep learning, and developed a communication system for quadriplegic patients can call the caregiver. METHODS: The communication system consists of 3 programs. The first program was developed for automatic capturing of eye images from the face using a webcam. It continuously captured and stored 15 eye images per second. Secondly, the captured eye images were evaluated for open or closed status by deep learning, which is a type of AI. Google TensorFlow was used as a machine learning tool or library for convolutional neural network. A total of 18,000 images were used to train deep learning system. Finally, the program was developed to utter a sound when the left eye was closed for 3 seconds. RESULTS: The test accuracy of eye status was 98.7%. In practice, when the quadriplegic patient looked at the webcam and closed his left eye for 3 seconds, the sound for calling a caregiver was generated. CONCLUSION: Our eye status detection software using AI is very accurate, and the calling system for the quadriplegic patient was satisfactory.
Artificial Intelligence
;
Caregivers
;
Humans
;
Learning
;
Machine Learning
;
Quadriplegia
;
Tracheostomy
;
Unsupervised Machine Learning
;
Voice
5.Gallbladder Cancer Incidentally Discovered after a Laparoscopic Cholecystectomy.
Kyung Sik KIM ; Woo Jung LEE ; Ho Geun KIM ; Hoon Sang CHI ; Byong Ro KIM
Journal of the Korean Surgical Society 1998;54(Suppl):1024-1031
A laparoscopic cholecystectomy has been accepted as one of the methods of treatment for patients with gallbladder(GB) pathology. Occasionally some cases can be diagnosed as cancer of the gallbladder incidentally after a laparoscopic cholecystectomy. We did 855 laparoscopic cholecystectomies from September 1991 to July 1996 and found 9 GB cancer patients after the operation. Most of the patients with GB cancer have a poor prognosis, but recently there have been some reports with good prognoses in this group of patients. The incidence of incidental GB cancer in laparoscopically resected GB specimens was 1.1% (9/855). The age distribution was between 44 and 72 yrs. Among the 9 cancer patients, 6 patients were found to have a GB mass as a result of the preoperative ultrasound examination. Four patients had mucosa-confined cancer and did not undergo any further treatment. One patient had mucosa confined cancer with a residual tumor in the cystic duct resection margin and underwent segmental resection of the liver (IVa & V) and segmental resection of the common bile duct, including dissection of the pericholedochal lymph node. The other four patients had advanced GB cancer with subserosal invasion. One patient underwent segmental resection of the liver (IVa & V) and segmental resection of the common bile duct, including dissection of the pericholedochal lymph node, and the other patient received a pericholedochal lymph node dissection only. The follow-up period ranged from 39 months to 3 months. Only one patient, who had mucosa-confined cancer with cystic duct invasion, died from lung metastasis with local recurrence of the midclavicular trocar site at 16 months after the laparoscopic cholecystectomy, but the other 8 patients have been doing well until now. We recommend a habit of opening the gallbladder, examining the gross pathologic features, and performing a frozen-section examination in patients where GB cancer is suspected. During that procedure, a careful isolation technique (careful dissection and delivery of the specimen in vinyl bag is vital) for preventing tumor implantation.
Age Distribution
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Cholecystectomy, Laparoscopic*
;
Common Bile Duct
;
Cystic Duct
;
Follow-Up Studies
;
Gallbladder Neoplasms*
;
Gallbladder*
;
Humans
;
Incidence
;
Liver
;
Lung
;
Lymph Node Excision
;
Lymph Nodes
;
Mucous Membrane
;
Neoplasm Metastasis
;
Neoplasm, Residual
;
Pathology
;
Prognosis
;
Recurrence
;
Surgical Instruments
;
Ultrasonography
6.5' CpG island methylation of p16 is associated with absence of p16 expression in glioblastomas.
Sung Hye PARK ; Kyeong Cheon JUNG ; Jae Y RO ; Gyeong Hoon KANG ; Shin Kwang KHANG
Journal of Korean Medical Science 2000;15(5):555-559
Recent evidence shows that transcriptional silencing as a consequence of hypermethylation of CpG islands is an important mechanism in the inactivation of p16INK4 tumor suppressor gene. This study is designed to clarify the significance of p16INK4 hypermethylation in 23 cases of glioblastomas (GBMs) by methylation-specific polymerase chain reaction (PCR) and p16 immunostaining. Fourteen cases (60.9%) out of 23 GBMs revealed hypermethylation on p16. p16 immunostaining revealed that 13 (93%) of these 14 hypermethylation cases showed complete loss of immunoreactivity and only one (7%) case retained immunoreactivity. Among 9 methylation-negative cases, 4 were immunonegative, which might be related to mutations or deletions other than hypermethylation. The most significant finding was that of 17 cases with immunonegativity, 13 cases (76.5%) showed hypermethylation. We reconfirmed that p16 hypermethylation may be one of the major mechanisms of tumorigenesis of GBMs and the results between the methylation specific-PCR study and p16 immunostaining had a good correlation.
5' Untranslated Regions/metabolism*
;
5' Untranslated Regions/genetics
;
Adult
;
Antisense Elements (Genetics)
;
Brain Neoplasms/pathology
;
Brain Neoplasms/genetics*
;
Brain Neoplasms/chemistry
;
CpG Islands/physiology*
;
DNA Methylation*
;
Female
;
Gene Silencing/physiology
;
Glioblastoma/pathology
;
Glioblastoma/genetics*
;
Glioblastoma/chemistry
;
Human
;
Male
;
Middle Age
;
Polymerase Chain Reaction
;
Protein p16/genetics*
;
Protein p16/analysis
7.Delapril Monotherapy in the Treatment of Essential Hypertension.
Young Hoon KIM ; Chang Kyu PARK ; Hong Seog SEO ; Wan Joo SHIM ; Dong Joo OH ; Jung Euy PARK ; Young Moo RO
Korean Circulation Journal 1992;22(5):844-851
BACKGROUND: Delapril, a recently developed nonsulfhydry(SH) angiotensin converting enzyme inhibitor, was known to have more prolonged duration of action. In order to investigate the efficacy and safety of delapril, patients with essential hypertension were studied. METHODS: The study subject consisted of 37 patients(mean age : 50.4 years, 15 male, 22 female). Because 4 of 37 patients dropped out due to side effects of delapril, the antihypertensive efficacy was evaluated in the remaining 33 patients. Delapril was administered orally in a daily dose of 30-120mg in two divided doses for 10 weeks after the administration of a placebo for 2 weeks. RESULTS: Delapril decreased systolic blood pressure significantly from a baseline value of 162.4+/-18.8mmHg to 142.9+/-20.9mmHg(p<0.01) and diastolic blood pressure from 103.2+/-5.0mmHg to 92.8+/-10.4mmHg(p<0.01) after 2 weeks of therapy, and maintained this effect throughout the study period. The efficacy rates were 72% for systolic pressure, 75% for diastolic pressure. The cumulative efficacy rate was 48% at 30mg/day, 66% at 60mg/day, and 73% at 120mg/day. Heart rate did not change until after 8 weeks, when they modestly decreased(p<0.05), through the 10th week(NS). Side effects were noticed in 12 out of 37 cases(32.4%). The main symptoms included dry cough(7 cases, 18.9%), headache(2 cases, 5.4%), dizziness(1 case, 2.7%), dry mouth(1 case, 2.7%) and angioedema(1 case, 2.7%). Six of the 7cases of dry cough were in women, and 3 caes discontinued the drug due to intractable cough. Angioedema in the oropharynx occurred in 1 patient and caused severe dyspnea which was relieved by the discontinuation of the medication. There was no significant change in CBC and biochemical variables. CONCLUSIONS: A daily dose of delapril in two divided doses is effective in decreasing blood pressure in patients with essential hypertension, and safe when an awareness of possible side effects is taken into account.
Angioedema
;
Blood Pressure
;
Cough
;
Dyspnea
;
Female
;
Heart Rate
;
Humans
;
Hypertension*
;
Male
;
Oropharynx
;
Peptidyl-Dipeptidase A
8.Role of KATP Channel During Sustained Ventricular Fibrillation.
Young Hoon KIM ; Hui Nam PAK ; Se Jung KIM ; Gyo Seung HWANG ; Soo Jin LEE ; Wan Joo SHIM ; Dong Joo OH ; Young Moo RO
Korean Circulation Journal 2001;31(3):359-359
OBJECTIVES: To investigate the role of ATP-sensitive potassium channel (KATP) during sustained ventricular fibrillation (VF), the effects of gliburide, a specific blocker of KATP channel and PCO400, an KATP opener, were studied in isolated and perfused swine right ventricular free walls (n=). METHODS: Recording of single cell transmembrane potentials was performed and constructed action potential duration restitution (APDR) curve by plotting APD 90%(APD90) versus preceding diastolic interval (DI). RESULTS: All isolated tissues fibrillated spontaneously. In this preparation, stable VF could persist over a 4-hour period if it was allowed to continue undisturbed (n=). Gliburide (1-5 uM) increased DI without significant changes in APD90 during VF, resulting in more regularization of VF. Higher concentration (10-20 uM) increased both APD90 and DI, and converted to monomorphic ventricular tachycardia (MVT) through the transitional period characterized by APD alternans. PCO400 (1-2.5 uM) caused a significant shortening of APD during MVT and a period of APD alternans became more evident before conversion from MVT to VF. Gliburide eliminated profibrillatory effect of PCO400. This antifibrillatory action of gliburide was accompanied by gradual decrease in the maximum slope of APDR curve during VF. CONCLUSION: KATP channel blockade causes a transition from VF to MVT via lengthening of DI and APD alternans, concomitantly with a reduction of the slope of APD restitution curve.
Action Potentials
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Membrane Potentials
;
Potassium Channels
;
Swine
;
Tachycardia, Ventricular
;
Ventricular Fibrillation*
9.A case of hypomelanosis of Ito accompanying ureteral duplication and hypomelanotic scalp hair.
Dong Woo SON ; Beom Soo PARK ; Heon Seok HAN ; Hae Il JUNG ; Yong CHOI ; Hyung Ro MOON ; Seon Hoon KIM ; Hwang CHOI
Journal of the Korean Pediatric Society 1991;34(2):281-286
No abstract available.
Hair*
;
Hypopigmentation*
;
Scalp*
;
Ureter*
10.Gallbladder Carcinoma Diagnosed after Laparoscopic Cholecystectomy.
Hyo Sang LEE ; Kyung Sik KIM ; Jin Sub CHOI ; Sang Hoon LEE ; Woo Jung LEE ; Byong Ro KIM
Korean Journal of Hepato-Biliary-Pancreatic Surgery 2002;6(1):73-79
BACKGROUND/AIMS: Laparoscopic cholecystectomy has become popular. Occasionally, unsuspected gallbladder carcinoma is diagnosed after the operation by pathologic examination, incidentally. And even when the gallbladder carcinoma is suspected preoperatively, it is determined whether or not the additional radical operation will proceed, according to the pathologic diagnosis after laparoscopic cholecystectomy. Multiple staging systems have been described, including the modified Nevin classification (Donohue et al 1990, Nevin et al 1976), the AJCC TNM staging system, and there are controversies in the surgical management of gallbladder carcinoma for each stage. The purpose of this study was to evaluate the role and the meaning of the laparoscopic cholecystectomy in the surgical management of the gallbladder carcinoma. METHODS: A retrospective analysis was made of 24 patients with gallbladder carcinoma that was confirmed by pathologic diagnosis after laparoscopic cholecystectomy in Severance Hospital between January 1993 and Feburary 2002. RESULTS: Gallbladder carcinoma was found in 1.1% of the 2141 cholecystectomy specimens. Gallbladder carcinoma was suspected preoperatively in 11 patients (45.8%). The location of the lesions was the serosal side in 16 patients (66.7%), the liver bed side in 1 patient, and undetermined in 7 patients. The histologic type was adenocarcinoma in all patient, and well differentiated in 16 patients (66.7%), moderate and poorly differentiated in 8 patients (33.3%). According to the AJCC TNM staging system, there were 13 stage I (54%), 5 stage II (20.8%), 2 stage III (8.3%), 4 stage IV (16.7%). The lymph node metastasis was observed in 4 patients (16.7%). In 18 patients (75%), only laparoscopic cholecystectomies were performed, and additional radical cholecystectomies were performed in 4 patients (16.7%). The patients with stage I and II tumor were alive without recurrence except 1 follow-up loss, and there was not any port site recurrence. CONCLUSION: Laparoscopic cholecystectomy is sufficient with stage I gallbladder carcinoma. It may be considered that the patient with stage II gallbladder carcinoma is closely followed without additional radical cholecystectomy after laparoscopic cholecystectomy, if properly selected. The use of vinyl bag for retrieval of specimen is recommended to avoid the port site recurrence. For advanced gallbladder carcinoma (stage III and IV), the additional radical cholecystectomy is recommended. When gallbladder cancer is suspected, an open operation should be performed with sufficient preoperative staging work-up.
Adenocarcinoma
;
Cholecystectomy
;
Cholecystectomy, Laparoscopic*
;
Classification
;
Diagnosis
;
Follow-Up Studies
;
Gallbladder Neoplasms
;
Gallbladder*
;
Humans
;
Liver
;
Lymph Nodes
;
Neoplasm Metastasis
;
Neoplasm Staging
;
Recurrence
;
Retrospective Studies