OBJECTIVE: The present study was designed to compare Global field Power Measurement and conventional method in P300 determination. METHOD: The subjects were composed of patients(N=20) with schizophrenia by DSM-IV and normal controls(N=20). The auditory event related potential P300 was measured by "oddball paradigm". P300 components were determined by Global Field Power Measurement and conventional method at 5 electrodes(Fz, Cz, Pz, T3, T4). RESULTS: P300 amplitudes of patients were smaller than those of controls across all electrodes and in both methods, but there was no differential power in P300 determination between two methods. Asymmetry of auditory event-related potential P300 was not shown between patients with schizophrenia and normal controls. CONCLUSION: It is implicated that it depends on clinical situations and research purposes what method of P300 determination will be more appropriate for patients with schizophernia.
Diagnostic and Statistical Manual of Mental Disorders ; Electrodes ; Event-Related Potentials, P300 ; Evoked Potentials ; Humans ; Schizophrenia

OBJECTIVE: The present study was designed to investigate whether asymmetry of auditory event-related potential P300 was shown in patients with schizophrenia or not. METHOD: The subjects were composed of patients(N=20) with schizophrenia by DSM-IV and normal controls(N=20). The auditory event related potential P300 was measured by "oddball paradigm". P300 component was determined by classic method at 5 electrodes(Fz, Cz, Pz, T3, T4). RESULTS: P300 amplitudes of patients were smaller than those of controls across all electrodes. Asymmetry of auditory event-related potential P300 was not shown between patients with schizophrenia and normal controls. CONCLUSION: It is implicated that auditory event-related potential P300 and its information processing should not be elicited asymmetrically in schizophrenia.
Automatic Data Processing ; Diagnostic and Statistical Manual of Mental Disorders ; Electrodes ; Event-Related Potentials, P300 ; Evoked Potentials* ; Humans ; Schizophrenia*

OBJECTS: This study was designed to investigate the characteristics of components of topographic auditory event-related potential P300 in the patients with schizophrenia and to evaluate the correlation between the findings of components of P300 and psychopathology. METHODS: The subjects consisted of 28 patients with schizophrenia and 28 normal controls who were matched by age and sex. The topographic auditory event-related P300 was recorded in oddball paradigm and analyzed by computerized brain mapping system. The latency of P300 was determined by global field power measurement. The psychopathology of the patients with chizophrenia were rated by PANSS. RESULTS: There were significant differences in both latency(schizophrenia 369.5+/-40.6msec, normal controls 332.6+/-34.8msec) and amplitude(schizophrenia: 4.1+/-3.1micro V, normal controls 6.7+/-3.2micro V). However, there was no difference in the electrode location of maximum area of P300 between the patients with schizophrenia and normal controls. The latency of P300 showed positive correlation and the amplitude showed negative correlation with PANSS scores of the patients with schizophrenia. CONCLUSION: The results implicate that the patients with schizoprenia might have mental dysfunction in the aspects of cognise process affected by both positive and negative symptoms.
Brain Mapping ; Electrodes ; Evoked Potentials* ; Humans ; Psychopathology* ; Schizophrenia*

Purpose: The results of a more than 10-year follow-up after total hip arthroplasties with circumferential and proximal porous-coated femoral stems were evaluated. Materials and Methods: Seventy-six patients (80 hips), who were operated on between Aug. 1991 and July 1994, were followed for more than 10 years after primary total hip arthroplasties using Multilock stems. The mean age at the time of the operations was 47.3 years old and the mean duration of follow-up was 12.3 years. The clinical results and radiological findings were evaluated. Results: The mean Harris hip scores improved from 54.7 points to 88.5 points at the time of the 10-year follow up. On the last follow-up radiograph, endosteal bone formation was observed in 70 hips (90%) and all femoral stems were biologically stable. Femoral osteolysis, which was linear in Gruen zone I and VII and mostly restricted to the proximal zones, was observed in 67 hips (84%), and no hip had distal osteolysis in the femur. There was no loosening, migration, or revisions of the stems. Conclusion: Total hip arthroplasties using circumferential and proximal porous coated Multilock femoral stems demonstrated stable osseous fixation and no distal osteolysis for a minimum 10-year follow-up; therefore, all stems were reported to have satisfactory outcomes. With improvement of cup design and liner wear, circumferential and proximal porous coating designs of femoral stems can be an alternative answer to mechanical failure due to aseptic loosening.
Arthroplasty ; Arthroplasty, Replacement, Hip* ; Femur ; Follow-Up Studies* ; Hip ; Humans ; Osteogenesis ; Osteolysis

This study was designed to investigate the clinical availability of topographic auditory event related potential P300 as a biological marker in patients with schizophrenia. The subjects were composed of normal controls(N=30) and patients(N=30) with schizophrenia by DSM-IV. Topographic auditory event related potential P300 and N100 were measured by "oddball paradigm", which was known as a standard method. Schizophrenics were evaluated twice, initial and follow-up, by 4 week interval. P300 latency and N100 latency were deter-mined by Global Field Power. At this time point the maximum amplitude and its location, according to X-Y coordinates, were determined in brain topography. Clinical symptoms were evaluated by Positive and Negative Syndrome Scale(PANSS). P300 latencies of normal controls, initial group of schizophrenics, and follow-up group of schizophrenics were 315.8+/-24.2msec, 403.8+/-42.3msec, and 364.7+/-43.2msec, respectively. P300 amplitudes of normal controls, initial group of schizophrenics, and follow-up group of schizophrenics were 8.8+/-2.7microV, 4.4+/-1.9microV, and 4.4+/-2.5microV, respectively. They had significantly different P300 latencies one another by measuring ANCOVA, of which covariables were N100 latency, age, and CCP(correct counted percent)(p<0.01). X-Y coordinates was not significant. In P300, there were some different characters between normal controls and schizophrenics even though excluding N100, which was supposed to be exogeneous component by external stimuli. When clinical symptoms were improved, P300 latency was decreased. However, P300 amplitude was not changed. These results suggest that P300 woald be available clinically as a biological marker, P300 latency be a state marker, and P300 amplitude be a trait marker in schizophrenia.
Biomarkers* ; Brain ; Diagnostic and Statistical Manual of Mental Disorders ; Follow-Up Studies ; Humans ; Schizophrenia*

OBJECTIVE: The purpose of this study is to determine whether patients with alcohol dependence do have brain dysfunction by auditory event related potential P300, EEG, and neuro-cognitive function test or not. METHODS: Subjects were composed of patients with alcohol dependence (N=33) and normal controls (N=67). P300 was determined by conventional method, Global Field Power method, and modified method. Also Korea Wechsler Intelligence Scale, Wechsler Memory Scale, and Trail Making B were tested. Spectral EEG was analyzed by the ranges of Hz, delta (delta, 1-3.5Hz), theta (theta, 4-7.5Hz), alpha(alpha, 8-13Hz), and beta(beta, 13.5-18Hz), and compared by relative power. RESULTS: In patients with alcohol dependence, P300 was smaller and later, and there was no difference between the measurement methods of P300. Lower IQ score was shown in patients with alcohol dependence, but it did not affect the P300 results. It took more time to perform Trail Making B test in patients with alcohol dependence, but there was no difference between groups in Wechsler Memory Scale. Spectrum EEG was shown as similar patterns. CONCLUSION: It suggests that patients with alcohol dependence have brain dysfunction in some neurophysiological aspects, regardless of intelligence. And frontal lobe dysfunction might be more severe than temporal one in patients with alcohol dependence.
Alcoholism* ; Brain ; Electroencephalography* ; Frontal Lobe ; Humans ; Intelligence ; Korea ; Memory

OBJECTS: This study was designed to make a comparison between methods to determine the components of topographic auditory event related potential P300. METHODS: The subjects were consisted of 44 normal controls and 44 patients with schizophrenia diagnosed by DSM-IV. The topographic auditory event related P300 was recorded in oddball paradigm. The components of P300, including latency, amplitude, and location of maximum amplitude in X-Y coordinates, were analized by computerized EP mapping system. The latency of P300 was determined by both global field power measurement and classic method. RESULTS: There was difference between two groups in latency(DF=1, F=35.28, P= 0.0001) and amplitude(DF=1, F=36.62, P=0.0001), but not in X coordinate(DF=1, F=0.37, P=0.55) and Y coordinate(DF=1, F=2.00, P=0.16). There was no difference between two mothods in latency(DF=1, F=0.04, P=0.85), in amplitude(DF=1, F=0.07, P=0.79), in X coordinate(DF=1, F=0.07, P=0.79), and in Y coordinate(DF=1, F=0.03, P=0.86). CONCLUSION: The results suggested that two methods to determine the components of topographic auditory event related potential P300 should be available for both research and clinical application to date.
Brain* ; Diagnostic and Statistical Manual of Mental Disorders ; Event-Related Potentials, P300* ; Humans ; Schizophrenia

OBJECTS: This study was to examine the changes of components of topographic auditory event related potential P300 in normal aging process. METHODS: The subjects were consisted of 85(range of age ; 18-68), who were right handed and had education level at least over 12 years. They had no history of medico-surgical and psychiatric illness which could cause brain dysfunction, and had not any physical and mental illness on examination. The topographic auditory event related P300 was recorded in oddball paradigm and the components of P300 including latency, amplitude, and location of maximum amplitude in X-Y cordinates were analized by computerized EP mapping system. The latency of P300 was determined by both Global Field Power Measurement and classic method. RESULTS: In global field power measurement, the latency has been increased about by 1m sec per year(latency=299.9+1 X AGE). The location of maximum amplitude in X coordinate was moved by 0.018 per year toward left side(X=3.6-0.018 X AGE) and in Y coordinate by 0.017 toward frontal direction(Y=2.15+0.017 X AGE). In classic method the latency has been increased about by 0.82m sec per year(latency=304.76+0.82 X AGE). The location of maximum amplitude in X coordinate was moved by 0.011 per year toward left side(X=3.35-0.011 X AGE) and in Y coordinate by 0.025 toward frontal direction(Y=1.86+0.025 X AGE). The amplitudes were not changed in both methods. CONCLUSION: The results showed strong positive correlation between latency of P300 and aging process, and slight left frontal displacement of the location of maximum amplitude. These finding implicate that psychophysiological function expressed by P300 was declined in aging process and database of formal controls should be necessary for both research and clinical application.
Aging* ; Brain ; Education ; Hand

PURPOSE: We report the minimum 5-year follow-up results of total knee arthroplasty with anteroposterior glide LCS(R) CompleteTM. MATERIALS AND METHODS: From June 1999 to June 2000, we performed sixty-two primary total knee replacements with the anteroposterior glide LCS(R) CompleteTM. Fifty-eight cases were followed-up for a minimum of 5 years. The posterior cruciate ligaments were preserved in all the cases. RESULTS: The mean Hospital for Special Surgery Knee Score increased from 62.9 points preoperatively to 88.6 points at the most recent follow-up. The mean knee score of the American Knee Society increased from 56.9 points preoperatively to 90.8 points and the functional score increased from 39.8 points to 76.8 points at the most recent follow-up. The mean flexion contracture decreased from 11.5 degrees preoperatively to 1.6 degrees and the range of motion with flexion increased from 103.5 degrees to 112.2 degrees. There was no loosening, osteolysis, or measurable polyethylene wear in any of the cases. We experienced dislocation of the polyethylene liner and guide arm in one case, but there was no revision surgery performed due to loosening or infection. CONCLUSION: Anteroposterior glide LCS(R) CompleteTM demonstrated excellent clinical and radiological results in polyethylene wear and osteolysis; but there was no increased benefit in ranges of motion compared with fixed-bearing implants. Further follow-up is needed to obtain long-term clinical and radiological results.
Arm ; Arthroplasty* ; Arthroplasty, Replacement, Knee ; Contracture ; Dislocations ; Follow-Up Studies* ; Knee Joint ; Knee* ; Osteolysis ; Polyethylene ; Posterior Cruciate Ligament ; Range of Motion, Articular

PURPOSE: To evaluate the results of revision total hip arthroplasty using a Wagner SL revision stem. MATERIALS AND METHODS: This study reviewed 56 revisions of the femoral component performed using a Wagner stem in 55 patients between 1992 and 2001. The mean age of the patients at the time of the revision was 50 years. The mean follow up duration was 8.4 years (range, 5 to 12.5 years). The indication for revision was aseptic loosening in fifty-two hips, septic loosening in two and periprosthetic fractures in two. The pre-revisional femoral defects were classified according to the Paprosky classification system. A clinical evaluation and radiological assessment were performed. RESULTS: The mean Harris hip score improved from 47 points preoperatively to 87 points at the latest follow-up. There were 5, 20, 22 and 9 hips of type I, II, IIIA and IIIB according to the Paprosky classification system. Fifty two hips (93%) showed stable stems at the latest follow-up radiographs. The mean vertical subsidence of the stem was 6.2 mm (range, 0 to 21 mm). Severe progressive vertical subsidence in three hips and an infection in one occurred requiring repeat revision. CONCLUSION: For severe proximal femoral bone loss, the conical femoral revision stem with a fully grit-blasted surface produced satisfactory results with distal press-fit fixation. We can expect a decrease in the rate of mechanical failure rate of the stem by reducing the subsidence derived from the stem design itself.