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
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Diskectomy, Percutaneous
;
Equipment Design
;
Fluoroscopy
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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
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Caregivers
;
Humans
;
Learning
;
Machine Learning
;
Quadriplegia
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Tracheostomy
;
Unsupervised Machine Learning
;
Voice
5.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
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Adult
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Anterior Cruciate Ligament/*injuries/pathology/surgery
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Arthroscopy/*methods
;
Female
;
Humans
;
Knee Injuries/classification/*pathology/surgery
;
Magnetic Resonance Imaging
;
Male
;
Menisci, Tibial/*injuries/pathology/surgery
;
Middle Aged
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Reproducibility of Results
;
Retrospective Studies
6.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
7.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
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Cholecystectomy
;
Cholecystectomy, Laparoscopic*
;
Classification
;
Diagnosis
;
Follow-Up Studies
;
Gallbladder Neoplasms
;
Gallbladder*
;
Humans
;
Liver
;
Lymph Nodes
;
Neoplasm Metastasis
;
Neoplasm Staging
;
Recurrence
;
Retrospective Studies
8.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*
9.Ultrastructure of Rapidly Proliferating Preretinal Membrane of Very Extensive Ischemic Diabetic Retinopathy.
Young Sook PARK ; Jung Hoon HAN ; Yong Un SHIN ; Jae Yeon JUN ; Myung Kyu KO ; Byung Ro LEE
Journal of the Korean Ophthalmological Society 2010;51(11):1504-1512
PURPOSE: Using transmission electron microscopy (TEM), we studied the ultrastructures of rapidly proliferating preretinal membranes of young patients with very extensive ischemic proliferative diabetic retinopathy and diabetes with uncontrollable blood sugar level. METHODS: Nine cases of preretinal membranes were obtained from six eyes of five patients with rapidly progressed proliferative diabetic retinopathy (mean age, 35 years) during vitrectomy. We obtained each preretinal membrane bimanually as one single sheet membrane using intraocular scissors and forceps. Each tissue was fixed in 3% glutaraldehyde in the operating room. All specimens were prepared and studied using TEM. RESULTS: The preretinal membranes were composed of blood vessels and some interstitial cells. The blood vessels within the preretinal membranes varied in developmental stages, from the immature stage to the mature stage. The blood vessels were highly active, in that primitive cells showed a large nucleus and prominent chromatin clumping with abundant cytoplasm. Highly active fibroblast-like cells were also noted. CONCLUSIONS: We observed highly active angiogenesis in preretinal membranes, which rapidly proliferated in cases of severe retinal ischemia in young diabetes patients. This is the first report of such a finding, which may help to explain the poor prognosis of this disease modality.
Blood Glucose
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Blood Vessels
;
Chromatin
;
Cytoplasm
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Diabetic Retinopathy
;
Eye
;
Glutaral
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Humans
;
Ischemia
;
Membranes
;
Microscopy, Electron, Transmission
;
Operating Rooms
;
Prognosis
;
Retinaldehyde
;
Surgical Instruments
;
Vitrectomy
10.Clinical Efficacy and Safety of Intravenous levofloxacin in Patients of Abdominal Operati.
Yoon Seok CHAE ; Sub Jin CHOI ; Jong Hoon LEE ; Kyung Sik KIM ; Woo Jung LEE ; Byong Ro KIM
Korean Journal of Hepato-Biliary-Pancreatic Surgery 2001;5(1):169-173
BACKGROUND/AIMS: For the investigation of the efficacy and safety of intravenous levofloxacin, The clinical study was carrried out in 30 patients with abdominal operation, especially in hepatobiliary and pancreatic division. METHODS: Randomly chosen patients received intravenous levofloxacin (250mg bid) for only 7 days. Clinical and microbiological evaluation were conducted on the day of starting and finishing levofloxacin treatmeat except for the case of combined use of antibiotics. RESULTS: The most commonly isolated organism was staphylococcus aureus(33%, 3/9). The overall bacteriologic eradication rate was 67%, (6/9) with clinical success rate was 96%(29/30), There were no significant dverse effects to stop the administration of the drug. CONCLUSION: These results suggest that intravenous levofloxacin is effective and safe antibiotics in the fields management of abdominal operation especially in hepatobiliary and pancreas surgery.
Anti-Bacterial Agents
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Humans
;
Levofloxacin*
;
Pancreas
;
Staphylococcus