1.Anesthetic Management for Carotid Endarterectomy: case report.
Jong Hoon KIM ; Sun Ho KIM ; Sun Kook YOO ; Kyung Il WHANG
Korean Journal of Anesthesiology 1997;33(4):762-769
We have experienced an anesthetic management of 56-year-old male patient with carotid stenosis. Carotid endarterectomy was performed with processed electroencephalography (compressed spectral array, CSA) monitoring. Carotid endarterectomy has significant risk of perioperative stroke and myocardial infarction. For brain protection during carotid cross clamp, body temperature of patient was maintained at 33.5oC and thiopental was infused continuously to induce burst suppression. To maintain blood pressure during cross clamp, dopamine was infused continuously and phenylephrine was injected intermittently. CSA was performed to monitor thiopental-induced burst suppression and ischemic brain insult. After releasing carotid cross clamp, body temperature was raised to 35oC.
Blood Pressure
;
Body Temperature
;
Brain
;
Carotid Stenosis
;
Dopamine
;
Electroencephalography
;
Endarterectomy, Carotid*
;
Humans
;
Hypothermia
;
Male
;
Middle Aged
;
Myocardial Infarction
;
Phenylephrine
;
Stroke
;
Thiopental
2.Vestibuloneuritis Developed Concurrently in Ipsilateral Site with Herpes-Zoster Oticus Syndrome .
Gyu Cheol HAN ; Ju Hyoung LEE ; Joo Hyun WOO ; Jung Kook YOO ; Sun Hwa LIM
Journal of the Korean Balance Society 2004;3(1):187-191
BACKGROUND:Acute vestibular neuronitis is the disease of which the etiology and pathophysiology are largely unknown . But the viral infection and ischemia of the labyrinth and the vestibular nerve are considered as general etiology. This study was performed to support the viral infection rather than the ischemic theory. MATERIALS & METHODS:We studied seventy years old female patient who showed painful vesicles on left auricle and vertigo with spontaneous nystagmus to the right side. We performed physical examination, serologic test, ENG test, pure tone audiogram, brain magnetic resonance imaging and polymerase chain reaction. RESULTS:We found small vesicles and vascular injection in left EAC, herpes zoster IgG positive, spontaneous right beating in electronystagmograpy, 54% left canal paresis in Caloric test , decreasing left side Tc in velocity step rotatory test, decresed gain, deviation to left in symmetry and phase lead in sinusoidal harmonic acceleration test, normal range hearing in pure tone audiogram, microangiopathy on cortex in brain MRI and negative PCR. CONCLUSION:This case supports viral infection etiology rather than ischemia in vestibular neuritis. But more studies to find the etiology of vestibular neuronitis are required.
Acceleration
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Brain
;
Caloric Tests
;
Ear, Inner
;
Female
;
Hearing
;
Herpes Zoster
;
Herpes Zoster Oticus
;
Humans
;
Immunoglobulin G
;
Ischemia
;
Magnetic Resonance Imaging
;
Paresis
;
Physical Examination
;
Polymerase Chain Reaction
;
Reference Values
;
Serologic Tests
;
Vertigo
;
Vestibular Nerve
;
Vestibular Neuronitis
3.The Development and Application of Emergency Teleradiology(Medical Image Transmission) System with Personal Computer.
Sun Ho KIM ; Sun Kook YOO ; Sung Wook PARK ; Won Ki KIM
Journal of Korean Neurosurgical Society 1994;23(8):954-959
In the clinical practice of neurosurgery, there are frequent needs which require urgent communication between housestaff and attending physician due to the emergency situation. But, the traditional methods such as telephone communication were not sufficient and sometimes, result in misjudgement of patient's status. So, our research team develop the computer software which can be used for emergency surgical and medical decision making. This software can transmitted the high quality images of CT, MRI and other X-ray with the conventional telephone line and personal computer system.
Data Compression
;
Decision Making
;
Emergencies*
;
Humans
;
Magnetic Resonance Imaging
;
Microcomputers*
;
Neurosurgery
;
Telephone
;
Teleradiology
4.Non-linear Analysis of Single Electroencephalography (EEG) for Sleep-Related Healthcare Applications.
Chung Ki LEE ; Han Gue JO ; Sun Kook YOO
Healthcare Informatics Research 2010;16(1):46-51
OBJECTIVES: Soft-computing techniques are commonly used to detect medical phenomena and to help with clinical diagnoses and treatment. The purpose of this paper is to analyze the single electroencephalography (EEG) signal with the chaotic methods in order to identify the sleep stages. METHODS: Data acquisition (polysomnography) was performed on four healthy young adults (all males with a mean age of 27.5 years). The evaluated algorithm was designed with a correlation dimension and Lyapunov's exponent using a single EEG signal that detects differences in chaotic characteristics. RESULTS: The change of the correlation dimension and the largest Lyapunov exponent over the whole night sleep EEG was performed. The results show that the correlation dimension and largest Lyapunov exponent decreased from light sleep to deep sleep and they increased during the rapid eye movement stage. CONCLUSIONS: These results suggest that chaotic analysis may be a useful adjunct to linear (spectral) analysis for identifying sleep stages. The single EEG based nonlinear analysis is suitable for u-healthcare applications for monitoring sleep.
Delivery of Health Care
;
Electroencephalography
;
Humans
;
Light
;
Male
;
Regression Analysis
;
Sleep Stages
;
Sleep, REM
;
Young Adult
5.The Design of Wavelet-based Biological Signal CODEC for Telemedicine Application.
Jae Man HUH ; Sun Kook YOO ; Nam Hyun KIM
Journal of Korean Society of Medical Informatics 2001;7(4):33-40
In this paper, waveform preserving coding technique is proposed for the bio-signals based on wavelet transform local maxima representation. In order to efficiently encode the bio-signal, it utilize the inherent property of bio-signals that sharp waves corresponding to the local maxima in wavelet domain contain the most of the clinically significant information in general. The testing sets of ECG and EEG are experimented to select the appropriate wavelet basis and to demonstrate the usefulness regarding to coding efficiency. The spline basis is more suitable in designing the coder than the Harr basis since the spline basis produces less number of local maxima than the Harr basis. The proposed wavelet method based on spline basis outperforms the conventional subband coding technique in terms of wave form degradation and coding efficiency. The actual transmission experiment using external communication network and the general personal computer demonstrates the applicability to telemedicine system handling the bio-signals.
Clinical Coding
;
Electrocardiography
;
Electroencephalography
;
Microcomputers
;
Telemedicine*
;
Wavelet Analysis
6.Multiagent System using Data Mining Technique for the Management of Asthma in Mobile Computing Environments.
Sung Rim KIM ; Joon Hee KWON ; Sun Kook YOO ; Chein Soo HONG
Journal of Korean Society of Medical Informatics 2004;10(3):311-319
OBJECTIVE: In the mobile computing environments, doctors or patients with mobile devices can access services at any time, any place. It makes chronic diseases, such as asthma care successively and in long-term. This paper presents a new multiagent system using data mining technique for the management of asthma in mobile computing environments. METHODS: In mobile computing environments, mobile communication is prone to disconnection. To use the services when disconnected, we locally store the recommendation information in mobile devices. Then, when user reconnects network, the new information is delivered in mobile devices. Because mobile devices have a limitation of resource, we store only patterns and recent data. We adopted data mining technique from the large pool of accumulated patients data can be utilized to summarize observed correlations and trends. RESULTS: We propose multiagent system composed of a Pattern Agent, a Selection Agent and a Recommendation Agent. They make asthmatic-caring system access effectively in mobile computing environments. We describe the underlying architecture and the process. Then we make a prototype with asthmatic patients data in the Severance Hospital in Korea. CONCLUSION: The results of our study can be contributed to aid management of asthma in mobile computing environments.
Asthma*
;
Chronic Disease
;
Data Mining*
;
Humans
;
Korea
;
Telemedicine
7.Plastination: An Improved Method for Preservation of Pathology Specimens.
Chong Woo YOO ; Min Ho CHOO ; Sa Sun CHO ; Sang Kook LEE ; Je Geun CHI ; Woo Ho KIM
Korean Journal of Pathology 1998;32(7):531-534
The gross tissue specimens are a valuable aid to the teaching of pathology and anatomy. However, traditional methods for storage and handling of them are discouragingly difficult and, recently, minimal surgical resections as well as preoperative interventions make it more difficult to have instructive gross specimens. Plastination is a process of tissue preservation by impregnation with silicone polymers or epoxy resins. The process in our study involves dehydration by cryosubstitution in aceton, defatting, forced impregnation of silicon polymer in a vacuum, curing and finishing. We submitted 40 surgically resected specimens to plastination. The resulting specimens are odorless, relatively dry, durable, life-like, non-hazardous, maintenance-free, and do not deteriorate with time. Plastinated specimens are a useful adjunct to the teaching of pathology, particularly suited for use in small groups, and appropriate method of tissue preservation. They are much preferred to wet preparation and conventional pots by both students and teachers owing to their accessibility, superior illustrative powers, and comparative ease of interpretation.
Dehydration
;
Epoxy Resins
;
Humans
;
Pathology*
;
Polymers
;
Silicones
;
Tissue Preservation
;
Vacuum
8.Texture Analysis of Supraspinatus Ultrasound Image for Computer Aided Diagnostic System.
Byung Eun PARK ; Won Seuk JANG ; Sun Kook YOO
Healthcare Informatics Research 2016;22(4):299-304
OBJECTIVES: In this paper, we proposed an algorithm for recognizing a rotator cuff supraspinatus tendon tear using a texture analysis based on a histogram, gray level co-occurrence matrix (GLCM), and gray level run length matrix (GLRLM). METHODS: First, we applied a total of 57 features (5 first order descriptors, 40 GLCM features, and 12 GLRLM features) to each rotator cuff region of interest. Our results show that first order statistics (mean, skewness, entropy, energy, smoothness), GLCM (correlation, contrast, energy, entropy, difference entropy, homogeneity, maximum probability, sum average, sum entropy), and GLRLM features are helpful to distinguish a normal supraspinatus tendon and an abnormal supraspinatus tendon. The statistical significance of these features is verified using a t-test. The support vector machine classification showed accuracy using feature combinations. Support Vector Machine offers good performance with a small amount of training data. Sensitivity, specificity, and accuracy are used to evaluate performance of a classification test. RESULTS: From the results, first order statics features and GLCM and GLRLM features afford 95%, 85%, and 100% accuracy, respectively. First order statistics and GLCM and GLRLM features in combination provided 100% accuracy. Combinations that include GLRLM features had high accuracy. GLRLM features were confirmed as highly accurate features for classified normal and abnormal. CONCLUSIONS: This algorithm will be helpful to diagnose supraspinatus tendon tear on ultrasound images.
Classification
;
Data Interpretation, Statistical
;
Entropy
;
Image Processing, Computer-Assisted
;
Rotator Cuff
;
Sensitivity and Specificity
;
Subject Headings
;
Support Vector Machine
;
Tears
;
Tendons
;
Ultrasonography*
9.Integrated Solution for Physical Activity Monitoring Based on Mobile Phone and PC.
Mi Hee LEE ; Jungchae KIM ; Sun Ha JEE ; Sun Kook YOO
Healthcare Informatics Research 2011;17(1):76-86
OBJECTIVES: This study is part of the ongoing development of treatment methods for metabolic syndrome (MS) project, which involves monitoring daily physical activity. In this study, we have focused on detecting walking activity from subjects which includes many other physical activities such as standing, sitting, lying, walking, running, and falling. Specially, we implemented an integrated solution for various physical activities monitoring using a mobile phone and PC. METHODS: We put the iPod touch has built in a tri-axial accelerometer on the waist of the subjects, and measured change in acceleration signal according to change in ambulatory movement and physical activities. First, we developed of programs that are aware of step counts, velocity of walking, energy consumptions, and metabolic equivalents based on iPod. Second, we have developed the activity recognition program based on PC. iPod synchronization with PC to transmit measured data using iPhoneBrowser program. Using the implemented system, we analyzed change in acceleration signal according to the change of six activity patterns. RESULTS: We compared results of the step counting algorithm with different positions. The mean accuracy across these tests was 99.6 +/- 0.61%, 99.1 +/- 0.87% (right waist location, right pants pocket). Moreover, six activities recognition was performed using Fuzzy c means classification algorithm recognized over 98% accuracy. In addition we developed of programs that synchronization of data between PC and iPod for long-term physical activity monitoring. CONCLUSIONS: This study will provide evidence on using mobile phone and PC for monitoring various activities in everyday life. The next step in our system will be addition of a standard value of various physical activities in everyday life such as household duties and a health guideline how to select and plan exercise considering one's physical characteristics and condition.
Acceleration
;
Cellular Phone
;
Deception
;
Family Characteristics
;
Metabolic Equivalent
;
Monitoring, Ambulatory
;
Motor Activity
;
MP3-Player
;
Running
;
Walking
10.Design of an emergency teleradiology system based on progressive transmission.
Sun Kook YOO ; Sun Ho KIM ; Nam Hyun KIM ; Yong Goo KIM
Yonsei Medical Journal 1995;36(5):426-437
In clinical surgery, there are frequent needs for communication between the house staff and the attending physician in an emergency situation. To overcome the limitation of voice communication through the telephone line, we have designed an 'emergency teleradiology system' which can be used for emergency surgical and medical decision making. This system can transmit the high quality images of CT, MRI, and other X-ray data using a PC attached to a modem through the conventional telephone line. It is based on the progressive transmission system which enables the successive update of a received image. The iterative residual coding/decoding algorithm efficiently compresses the image to maximally utilize the low bandwidth PSTN channels. This system also satisfies design requirements such as low-cost, ease of operation, fast transmission, and interactive image communication including voice. Test results using several CT, MR, and X-ray images evaluate the compression performance, image quality, transmission time and computational time of the coding and decoding processes, thus demonstrate the usefulness of this system in an emergency situation.
Algorithms
;
Human
;
Image Processing, Computer-Assisted
;
*Information Systems
;
Software Design
;
Support, Non-U.S. Gov't
;
Teleradiology/*methods