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.Preoperative Chemoradiation and Pancreaticoduodenectomy with Portal Vein Resection for Localized Advanced Pancreatic Cancer.
Yoon Seok CHAE ; Woo Jung LEE ; Jong Hoon LEE ; Kyung Sik KIM ; Byong Ro KIM
Journal of the Korean Surgical Society 2001;60(3):349-354
PURPOSE: Chemoradiation therapy prior to pancreaticoduodenectomy has several effects. First, it ensures that patient who undergo resection subsequently complete multimodality therapy and helps to avoid resection in patients with rapid progressive disease. Second, it allows radiation therapy to be delivered to well oxygenated cells before surgical devasculation. Finally, in such cases there is a chance of resection of unresectable pancreatic cancer by downstaging. METHODS: A patient with cytologic proof of localized adenocarcinoma of the pancreatic head recieved preoperative chemoradiation (Taxol, 50 mg/m2 IV for 3 hours weekly 3 cycles, Gemcytabine 1,000 mg/m2/day IV for 3 days weekly 2 cycles, 4,500 cGy) with the intent of proceeding to resection, Restaging was performed by computed tomography and magnetic resonance imaging every months from 5 weeks due to the ongoing decreasing of tumor size following the completion of chemoradiation. Upon laparotomy, the patient was found to not have any suspected metastatic disease and the tumor size was 2 3 cm on the pancreas head infiltrating to the portal vein approximately 3 cm in length along right side. Pancreaticoduodenectomy was performed with partial portal vein and superior mesenteric vein resection followed by reconstruction of the vascular anastomosis by using the right side internal jugular vein. Perioperative complication did not occur. RESULTS AND CONCLUSION: Preoperative chemoradiation of localized advanced pancreatic has a low incidence of operative complication and enhanced resectability.
Incidence
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Adenocarcinoma
;
Neoplasm Metastasis
;
Pancreatic Neoplasms
6.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*
;
Cell Differentiation
;
Female
;
Frozen Sections
;
Humans
;
Male
;
Prognosis
;
Recurrence
7.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
;
Humans
;
Infarction
;
Myocardial Infarction*
;
Stroke Volume
;
Ventricular Remodeling*
8.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
;
Celiprolol*
;
Chemistry
;
Cough
;
Diarrhea
;
Dyspnea
;
Flushing
;
Headache
;
Heart Rate
;
Humans
;
Hypertension*
;
Male
9.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
10.Comparative anatomical characteristics of cardiac valves in animals.
Chang Hoon NAM ; Hak Young KIM ; Chunmei LIN ; Jung Min YON
Journal of Biomedical Research 2014;15(1):19-23
Although various animals have been used as models of cardiac valvular diseases in humans, the structural characteristics of cardiac valves in animals remain unclear. In this study, we investigated cardiac valves in representative animal models for the purpose of comparative anatomy. Adult hearts from three dogs, four goats, six rabbits, and six fowls were fixed with 10% neutral-buffered formalin and analyzed gross-anatomically. Cardiac appearance was spherical or oval in dogs, goats, and rabbits, whereas it had a long conical shape in fowls. Left atrioventricular (AV) valve was composed of membranous septal and parietal cusps connected to two papillary muscles in all animals. The right AV valve was composed of membranous septal, parietal, and angular cusps with three papillary muscles in dogs and goats, membranous septal and parietal cusps attached to four papillary muscles in rabbits, and a single muscular plate without any papillary muscles and chorda tendinae in fowls. Aortic valves with thin membranous right, left, and septal semilunar cusps in dogs, goats, and rabbits had a thick membrane with a bended free border in fowls. Pulmonary valve (PV) with membranous right, left, and intermediate semilunar cusps made a large central hole by being closely attached to the surrounding wall in dogs, goats, and rabbits, whereas it protruded into half of the lumen as a thick membrane in fowls. The membranous cusp of the PV was composed of several layers in dogs and goats but was a single layer in rabbits and fowls. These findings indicate that even if animals have two completely separated atria and ventricles each, cardiac valves have species-specific morphological characteristics, especially between mammals and fowls.
Adult
;
Anatomy, Comparative
;
Animals
;
Aortic Valve
;
Dogs
;
Formaldehyde
;
Goats
;
Heart
;
Heart Valves*
;
Humans
;
Mammals
;
Membranes
;
Models, Animal
;
Papillary Muscles
;
Pulmonary Valve
;
Rabbits
;
Rabeprazole