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.Ventricular Remodeling after Acute Myocardial Infarction.
Wan Joo SHIM ; Chang Gyu PARK ; Young Hoon KIM ; Hong Seog SEO ; Dong Joo OH ; Jung Euy PARK ; Young Moo RO
Korean Circulation Journal 1993;23(6):921-927
BACKGROUND: Left ventricular dilatation after acute myocardial infarction is caused by infarct expansion and compensatory dilatation of noninfarct area. This study was done to investigate the contributory topographical change of left ventricle to left ventricular dilatation after acute myocardial infarction. METHODS: 24 first acute myocardial infarction was studied with 2-dimensional echocardiography serielly. First study was done at 7days and second study was done 9 months after an infarction attack. Left ventricular volume was measured by Simpson's method in end-diastolic frame and change of end diastolic left ventricular surface area was measured in apical 4 chamber view. Left ventricular surface area was devided by ischemic(noncontraction) and nonischemic(contracting) area by connecting central point of long axis of left ventricle and the junction of dyssynergic motion and normal motion point in outer rim of left ventricle in end diastolic frame of apical 4 chamber view. RESULTS: Mean left ventricular end-diastolic volume at entry was 114+/-23ml and increased to 121+/-27ml at 9 months after acute myocardial infarction in whole group(p=0.02). In a subgroup of anterior infarction, the left ventricular surface area was increaed in 9 cases with increared left ventricular volume(34.8+/-5.1cm2 to 36.4+/-4.1cm2, p=0.02) and ischemic surface area did not change in these group. In 7 patients without increase in left ventricular volume, the left ventricular surface area did not change and ischemic surface area decreased(9.4+/-4cm2 to 8+/-3.2cm2, p=0.03) at 9 months. CONCLUSION: Thus the increase in left ventricular end-diastolic volume between 13 days and 9 months after acute myocardial infarction is considered to be a consequence of noninfarct ventricular area dilatation.
Axis, Cervical Vertebra
;
Dilatation
;
Echocardiography
;
Heart Ventricles
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Humans
;
Infarction
;
Myocardial Infarction*
;
Stroke Volume
;
Ventricular Remodeling*
6.Clinical Effect and Safety of Celiprolol in Patients with Essential Hypertension.
Chang Gyu PARK ; Young Hoon KIM ; Hee Nam PARK ; Hong Seog SEO ; Wan Joo SHIM ; Dong Joo OH ; Jung Euy PARK ; Young Moo RO
Korean Circulation Journal 1993;23(6):907-914
BACKGROUND: Celiprolol is a new generation beta-adrenoreceptor blocking agent with intrinsic sympathomimetic activity characterized by selective blockade of beta1 receptors and partial agonist activity at beta2 receptors. This study was designed to investigate the antihypertensive efficacy and safety of celiprolol in patients with essential hypertension. METHODS: The study subjects consisted of 36 patients(mean age : 55 years, 11 males, 25 females). Celiprolol was administered orally in a aily dose of 200-800mg once or two divided dose for 10 weeks after the admimstration of placebo for 2 weeks. RESULTS: Blood pressure was significantly reduced from 171+/-19/106.8mmHg to 153+/-20/92+/-12mmHg(p<0.01) after 2 week of therapy and this effect was maintained throughout the study periods. The efficacy rates were total 94%(marked improve : 53%, moderate improve : 22%, mild improve : 19%). The cumulative efficacy rate was 72% at 200mg/day, 91% at 400mg/day, and 94% at 800mg/day. Heart rate did not change throughout 10 weeks. There were no significant change in hematologic and blood chemistry variables. During the period of medication, headache developed in 3 cases(8%) and each of dry cough, dyspnea, epigastric pain and diarrhea and facial flushing developed in 1 case(2.8%) but they were tolerable. CONCLUSIONS: This results suggest that celiprolol is effective and safe drug in the treament of patients with essential hypertension.
Blood Pressure
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Celiprolol*
;
Chemistry
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Cough
;
Diarrhea
;
Dyspnea
;
Flushing
;
Headache
;
Heart Rate
;
Humans
;
Hypertension*
;
Male
7.Intra-articular Patterns of Bucket Handle Meniscal Tears and Its Relation to Reducibility.
Hong Chul LIM ; Ji Hoon BAE ; Taik Sun KIM ; Jae Hyuk YANG ; Sung Chul PARK ; Jung Ro YOON
Clinics in Orthopedic Surgery 2012;4(2):129-133
BACKGROUND: The purpose of this study was to assess the intra-articular patterns in the rotational deformities of bucket handle meniscal tears (BHMTs) based on arthroscopic findings and their clinical relevance. METHODS: From 2004 to 2009, 42 patients with a BHMT diagnosed by magnetic resonance imaging underwent arthroscopic surgery. The arthroscopic data (all procedures were recorded) were evaluated retrospectively, and BHMTs were classified according to the rotational directions of centrally displaced fragments. To assess the reliability of the agreement in this classification, 2 orthopedic surgeons re-classified BHMTs, 1 week after first trial. Intra- and interobserver reliabilities were assessed using kappa statistics. In addition, we address specific tear patterns, associated anterior cruciate ligament injury, medio-lateral difference, reducibility, chronicity, and reparability. RESULTS: Most of the tears could be categorized into one of 3 morphologic patterns. Of the tears, 4.8% could not be categorized. BHMTs were classified, based on the rotational directions of centrally displaced fragments, as follows; the upward rotation group (type 1), the downward rotation group (type 2) and the reverse group (type 3). The most common intra-articular pattern was type 1 (29 patients, 69%). The occurrence of the other patterns was: type 2 in 7 patients (16.7%), type 3 in 4 patients (9.5%); we were not able to make a classification of type in 2 patients (4.8%). Intra-observer reliability was 0.86 in terms of kappa statistics, which implies almost perfect agreement. Mean interobserver reliability (0.73) showed substantial agreement. Type 1 and 2 tears were easily reduced, whereas all type 3 tears (4/4) needed additional procedures to achieve reduction. CONCLUSIONS: Based on arthroscopic findings, we describe a comprehensive BHMT classification scheme that encompasses 95.2% of all tears. Tear type was correlated with reducibility.
Adolescent
;
Adult
;
Anterior Cruciate Ligament/*injuries/pathology/surgery
;
Arthroscopy/*methods
;
Female
;
Humans
;
Knee Injuries/classification/*pathology/surgery
;
Magnetic Resonance Imaging
;
Male
;
Menisci, Tibial/*injuries/pathology/surgery
;
Middle Aged
;
Reproducibility of Results
;
Retrospective Studies
8.Transduodenal Local Resection for Low Risk Group Ampulla of Vater Cancer Patients.
Joon Seong PARK ; Dong Sup YOON ; Young Nyun PARK ; Woo Jung LEE ; Hoon Sang CHI ; Byong Ro KIM
Journal of the Korean Surgical Society 2004;66(5):404-408
PURPOSE: A carcinoma of the ampulla of Vater has more favorable prognosis than other malignant tumors of the periampullary region, because it is symptomatic at an early stage. However, local resection of an ampullary carcinoma remains controversial. The aim of this study was to evaluate the treatment results of ampulla of Vater carcinomas, according to operation type in low risk group patients. METHODS: The records of 17 low risk group patients, among 120 patients with ampulla of Vater cancer, who underwent curative surgery beyween 1992 and 2002, were reviewed. All specimens were critically reviewed by a single expert pathologist. The relationship between surgical outcomes and operation type were assessed. RESULTS: There were 10 men and 7 women, with a median age of 57.8 years. 13 of the 17 patients underwent the Whipples operation or a PPPD, and 4 underwent a transduodenal local resection (TDLR). The operation time was shorter in the TDLR group, and was statistically significant. Among the 17 patients, only one had a recurrence in the inguinal area 33 months after the PD. CONCLUSION: Transduodenal local resection is a recommendable operation for low risk Ampulla of Vater cancer patients. During the operation, it is essential to accurately evaluate the depth of invasion, cell differentiation and positivity of the resection margin using frozen sections.
Ampulla of Vater*
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Cell Differentiation
;
Female
;
Frozen Sections
;
Humans
;
Male
;
Prognosis
;
Recurrence
9.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
10.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
;
Membrane Potentials
;
Potassium Channels
;
Swine
;
Tachycardia, Ventricular
;
Ventricular Fibrillation*