1.An Experimental Study of the Effect of Vacuum Mixing on Fatigue Characteristics of Acrylic Bone Cement
Won Yong SHON ; Seok Hyun LEE ; Sang Won PARK ; Jeong Dae SUH
The Journal of the Korean Orthopaedic Association 1995;30(6):1618-1623
Contemporary cementing techniques improved the longevity of the cemented total hip replacement. The mechanical strength of acrylic bone cement can be changed by different handling techniques with reduction of the porosity of acrylic bone cement. The greatest improvement of the mechanical properties with reducing the porosity is that of the fatigue strength. We investigated the mechanical properties of the specimens of high viscosity, Palacos R(Merk, Darmstadt, FRG) bone cement with two mixing methods, hand and vacuum mixing. Vacuum mixing improved the ultimate tensile strength by 22.4% compared to hand mixing in previous study. For the uniaxial tension fatigue test, the specimens were cyclically loaded at a maximum stress of 25 MPa at a frequency of 2.5 Hz and to investigate the porosity, scanning electromicroscopic examination was taken in each hand mixed and vacuum mixed specimens. Scanning electromicrogram showed the vacuum mixed specimens to be the more uniform and free of small voids compared with the hand mixed specimens. The results of the fatigue test were analized using Weibull distribution of survival probability, the average number of cycles to failure was 1459±924 cycles in hand mixed specimens, in vacuum mixed specimens, 21491±14956 cycles. The average fatigue life of the vacuum mixed specimens was 15 times loanger than that of the hand mixed specimens by Weibull mean, this differene exists stastically within 95% confidence interval. We could suggest vacuum mixing technique as a method eliminating porosity in a chilled acrylic bone cement and thereby markedly improving the mechanical properties. In cemented joint replacement surgery, a vacuum mixing technique are recommended as a method of preparation of acrylic bone cement
Arthroplasty, Replacement, Hip
;
Clothing
;
Fatigue
;
Hand
;
Joints
;
Longevity
;
Methods
;
Polymethyl Methacrylate
;
Porosity
;
Tensile Strength
;
Vacuum
;
Viscosity
2.A x-ray and clinical study upon knee joint changes following surgical removal of discoid meniscus.
Hong Chul LIM ; Seok Hyun LEE ; Won Young SHON ; Dae Hyawan LEE ; Koung Wok NA
The Journal of the Korean Orthopaedic Association 1991;26(1):41-48
No abstract available.
Knee Joint*
;
Knee*
3.A Clinical Study of Meniscus Injury
Hong Chul LIM ; Seok Hyun LEE ; Won Yong SHON ; Dae Whan LEE
The Journal of the Korean Orthopaedic Association 1989;24(1):27-33
From September 1983 to June 1988, the authors could experience 104 cases of meniscal injury from 99 patients by arthroscopic examination. The results of this study may be summarized as follows : 1. There were noticed 35 cases of medial meniscus tear, 35 cases of lateral discoid meniscus tear, 12 cases of intact lat discoid meniscus, 1 case of medial discoid meniscus and 3 cases of lateral meniscal cyst. 2. Most common type of meniscal tear was bucket handle type (35 cases, 34.6%). 3. Most common site of rupture was posterior horn of medial meniscus. 4. Post operative results appeared related with the type of meniscus rupture and combined pathology of knee jont. Bucket handle type rupture was of good prognosis and meniscus lesions with chondromalacia was of poor prognosis.
Animals
;
Arthroscopy
;
Cartilage Diseases
;
Clinical Study
;
Horns
;
Humans
;
Knee
;
Menisci, Tibial
;
Pathology
;
Prognosis
;
Rupture
;
Tears
4.Topographic Changes of Ictal Hyperperfusion During Progression of Clinical Seizures.
Won Chul SHIN ; Seung Bong HONG ; Woo Suk TAE ; Young Min SHON ; Dae Won SEO ; Byoung Joon KIM ; Seung Chyul HONG ; Sang Eun KIM
Korean Journal of Nuclear Medicine 2001;35(6):352-363
No abstract available.
Seizures*
5.Hippocampus/Frontal Gyrus FLAIR Signal Intensity Ratio in Patients with Mesial Temporal Lobe Epilepsy.
Young Min SHON ; Seung Bong HONG ; Eun Kyung LEE ; Woo Suk TAE ; Dae Won SEO ; Won Chul SHIN
Journal of the Korean Neurological Association 2002;20(2):153-163
BACKGROUND: The typical MRI features of hippocampal sclerosis (HS) are volume loss and increased T2 weighted signal intensity. Hippocampal volumetry and T2 relaxometry are useful quantitative methods for presurgical diagnosis of HS, especially in the cases of mild, bilateral or focal hippocampal atrophies. We investigated the value of a new quantitative method using FLAIR (Fluid Attenuated Inversion Recovery) MR images compared to those of visual inter-pretation and MR volumetry. METHODS: Forty-five patients with mesial temporal lobe epilepsy (TLE) and 21 under-went volumetric MRI (T1-weighted, SPGR, T2 weighted, and FLAIR images). All patients underwent anterior temporal lobectomy with amygdalohippocampectomy., where visual analysis and hippocampal volumetry were performed. The absolute and normalized values of hippocampal FLAIR signal intensity [hippocampal FLAIR intensity/superior frontal FLAIR intensity=Hippocampal-Frontal Signal Intensity Ratio (HFSR)] were obtained from both normal subjects and patients with TLE. RESULTS: The pathology of resected hippocampus showed HS in all patients. Visual interpretation of presurgical MRI failed to lateralize HS in 10 patients (22.2%). Among these 10 patients, the HS was lateralized by HFSR method in seven patients (70%) [Five (50%) by right-to-left difference of HFSR and the other two (20%) by analysis of a longitudinal regional curve of HFSR] while it was further lateralized by hippocampal volumetry in only three. CONCLUSIONS: In presurgical evaluation of patients with TLE, the hippocampal FLAIR signal analysis appeared to be complementary to visual interpretation and MR volumetry.
Anterior Temporal Lobectomy
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Atrophy
;
Diagnosis
;
Epilepsy, Temporal Lobe*
;
Hippocampus
;
Humans
;
Magnetic Resonance Imaging
;
Pathology
;
Sclerosis
;
Temporal Lobe*
6.Comparison of the postoperative analgesic effect for infiltration between the popliteal artery and the capsule of the posterior knee and that of periarticular multimodal drug injection in total knee arthroplasty: retrospective study in the immediate postoperative period
Dae-Won JUNG ; Won-Yong SHON ; Seung-Suk SEO ; Ok-Gul KIM ; In-Seung LEE
The Journal of Korean Knee Society 2020;32(1):e1-
Background:
The aim of this study is to compare the postoperative analgesic effect of infiltration between the popliteal artery and the capsule of the knee (IPACK) and the effect of periarticular multimodal drug injection (PMDI) in addition to adductor canal block (ACB) after total knee arthroplasty.
Methods:
Among patients who received total knee arthroplasty from June 2017 to December 2017, 50 who underwent ACB with additional IPACK and 50 who received ACB with additional PMDI were selected for this study.We compared the postoperative pain numerical rating scale (NRS), the number of times patient-controlled analgesia was administered and the amount administered, the total amount of opioids given, and complications associated with the procedure between the two groups.
Results:
NRS measured at rest and 45° knee flexion at days 1 and 2 after surgery was significantly lower in the IPACK group than in the PMDI group. The resting NRS measured at day 3 after surgery was also significantly lower in the IPACK group than in the PMDI group, and the NRS at 45° knee flexion measured from day 3 to day 5 showed a significant reduction in the IPACK group. No complications relating to the procedure occurred.
Conclusions
IPACK may be a better option than PMDI for controlling acute phase pain in patients undergoing total knee arthroplasty.
7.Quality of Life Assessment in Epilepsy Patients With Topiramate.
Jung Hwa LEE ; Young Min SHON ; Dae Won SEO
Journal of the Korean Neurological Association 2010;28(4):283-290
BACKGROUND: Quality of life is important in epilepsy treatment. We evaluated the effect of topiramate on the quality of life in epilepsy patients and on the characteristics of the clinical features in patients with improved scores on the Quality of Life in Epilepsy Inventory-10 (QOLIE-10). METHODS: We included 631 adult epilepsy patients, who were followed for 16 weeks. We analyzed the effect of topiramate on QOLIE-10 score. The patients were classified into those with improved scores (IG) and those whose scores did not improve (NG). We compared each QOLIE-10 item and their clinical features between the IG and NG groups. RESULTS: All item scores, as well as the total score, improved after topiramate treatment. Comparison of the scores for each item showed that working and social factor differences of both the IG (>0.72) and NG groups (>0.80) were higher than for the other items. Age, gender, seizure onset, topiramate dose, adverse event, education level, employment, and migraine did not differ significantly between the IG and NG groups. The effect on seizure reduction was the most significant among the clinical features (P<0.001). The epilepsy syndrome, etiology, previous antiepileptic drugs (AEDs), and weight changes did not differ significantly between the two groups (P<0.05). CONCLUSIONS: Topiramate treatment can influence the quality of life in adult epilepsy patients, and especially work and social factors. Seizure reduction, epilepsy syndrome, etiology, previous AEDs, and weight change may be the most affected clinical factors in patients who have improved quality of life with topiramate.
Adult
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Anticonvulsants
;
Employment
;
Epilepsy
;
Fructose
;
Humans
;
Migraine Disorders
;
Quality of Life
;
Seizures
8.Preserved Responsiveness during Complex Partial Seizures ofMesial Temporal Lobe Epilepsy.
Young Min SHON ; Hahn Young KIM ; Dae Won SEO ; Seung Bong HONG
Journal of the Korean Neurological Association 2000;18(6):706-710
BACKGROUND: Preserved responsiveness (PR) can be observed in complex partial seizures (CPS) of temporal lobe epilepsy (TLE). In order to investigate the seizure lateralization value of PR and the degree of PR to different types of commands, we analyzed the CPS of the patients with mesial TLE. METHODS: The interviews consisted of four categories including verbal (word memory, orientation, verbal command) and nonverbal (motor command) questions. We defined PR as showing more than one correct response during the ictal period. The language dominance was determined in all patients by the Wada test. RESULTS: Out of 132 patients, eight showed PR during seizures. Two patients had 6 seizures arising from the dominant hemisphere (DHS) and six patients had 15 seizures arising from the nondominant hemisphere (NDHS). The number of total questions in the DHS was 65 (word memory; 6, orientation; 18, motor command; 23, verbal command; 18) and in the NDHS was 104 (15, 27, 28, 34 each). The number of PR was 15 (23.1%) in the DHS whereas 70 (67.3%) in the NDHS, indicating that PR was more frequently seen in the NDHS (p<0.001). The DHS showed no PR to word memory, orientation and only one to verbal command during seizures, but the NDHS had 6 PR for word memory, 20 for orientation and another 20 for verbal command. The number of PR to motor command was 14 (60.9%) in the DHS and 24 (85.7%) in the NDHS (p<0.05). CONCLUSIONS: The PR to word memory, orientation, and verbal command strongly suggests the NDHS. The PR to motor command was observed more frequently in the NDHS than in the DHS.
Epilepsy, Temporal Lobe*
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Humans
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Memory
;
Seizures*
;
Temporal Lobe*
9.A Case of Aphasic Status with Brain 99m-Tc Ethyl Cysteinate Diethylester Single Photon Emission Computed Tomography Demonstrating Focal Hyperperfusion.
Hahn Young KIM ; Young Min SHON ; Dae Won SEO ; Duk L NA
Journal of the Korean Neurological Association 2000;18(3):333-336
We present a 79-year-old male with aphasic status that was confirmed by a 99m-Tc ethyl cysteinate diethylester (ECD) single photon emission computed tomography (SPECT). He was admitted to our hospital due to a sudden onset of aphasia. In a Korean-version Western Aphasia Battery (K-WAB) test, the patient was diagnosed with Wernicke's aphasia (aphasia quotient (AQ)=54.50). In a brain magnetic resonance image (MRI) revealed the lesion of an old intracranial hemorrhage in the left posterior temporal area. An electroencephalography (EEG) showed continuous slowing in the left temporal area. SPECT demonstrated focal hyperperfusion in the left temporal cortex anterior to the lesion. After the administration of phenytoin, the aphasia was much improved (follow-up K-WAB : AQ=70.00). In follow-up studies two months later, EEG showed no interval changes and SPECT revealed no focal hyperperfusion in the left temporal area. Simple partial seizure is not easy to diagnose especially when manifesting with nonmotor symptoms such as aphasia. In this case, Wernicke's apha-sia was the only manifestation of epileptic seizure, the EEG did not show any definite epileptiform discharges. SPECT showed focal hyperperfusion in the left temporal area which was supposed to be a seizure focus. We conclude that SPECT might be useful in diagnosing a simple partial seizure manifesting as aphasia without EEG change.
Aged
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Aphasia
;
Brain*
;
Electroencephalography
;
Epilepsy
;
Follow-Up Studies
;
Humans
;
Intracranial Hemorrhages
;
Male
;
Phenytoin
;
Seizures
;
Tomography, Emission-Computed, Single-Photon*
10.Intracranial Ictal Electroencephalographic Patterns in Parietal Lobe Epileptic Seizures : Correlation with Surgical Outcome.
Young Min SHON ; Seol Heui HAN ; Dae Won SEO ; Hahn Young KIM
Journal of the Korean Neurological Association 2001;19(5):478-484
BACKGROUNDS: Parietal lobe epilepsy is uncommon and its intracranial ictal EEG findings have not been well elucidated. We investigated the ictal EEG patterns of epilepsy originating from the parietal lobe and its adjacent areas recorded by intracranial subdural electrode arrays. METHODS: The following intracranial ictal EEG patterns from twenty patients who underwent epilepsy surgery for medically intractable parietal lobe epilepsy were studied: 1) Anatomical ictal onset area [pure parietal (PP), combined parietal and extraparietal, such as fronto-parietal, temporo-parietal, etc. (EP)], 2) localization within the parietal lobe, 3) extent of the ictal onset zone, 4) the number of ictal onset zones, 5) frequency and waveform of ictal onset rhythms, and 6) type of spreading. RESULTS: Twelve patients (60%) were seizure-free (5 from PP, 7 from EP) and 8 were with persistent seizures (3 from PP, 5 from EP). Eight patients (40%) had ictal onset from PP and 12 were from EP. There were! Significant correlations with surgical outcome (p<0.05) in two variables: extent of ictal onset zone and type of spread. Patients with focal onset zones (n=9) showed better outcomes (eight are seizure-free) than those with wide ictal onset zones (4 out of 7 are seizure-free). Patients with slow spreading patterns showed better outcomes (12 from 16 are seizure-free) than those with fast spreading outcomes (all of them had persistent seizures). CONCLUSIONS: The extent of ictal onset zones correlates with surgical outcomes. The patterns of intracranial ictal EEG are helpful in predicting the surgical outcomes for parietal lobe epilepsy. (J Korean Neurol Assoc 19(5):478~484, 2001)
Electrodes
;
Electroencephalography
;
Epilepsy*
;
Humans
;
Parietal Lobe*
;
Rabeprazole*
;
Seizures