1.The experimental measurements of the effects of field size and shadow tray on the relative surface doses for Co-60 and 10 MV X-ray beams
In Wook CHOO ; Cham Il PARK ; Man Chung HAN
Journal of the Korean Radiological Society 1981;17(3):555-561
It is well known that high energy X and r-ray have high penetration power in tussue, but have lower survacedose which is called the “skin sparing effect”. However, the surface dose can be increased significantly by excessive electron contamination and it is an important factor intreatment planning in the presence of a blocktray, especially in isocentric set-up. So relaltive surface doses for 10MV-X-ray and Co-60 r-ray were measuredwith various field sizes and SSD with or withoug 1/4" lucite shadow tray, present in the beams, using pancakechamber and polystylene phantom. The results obtained are as follows. 1. A rapid increase in surface dose isapparant with increasing field size in 10MV X-ray and Co-60 r-ray. 2. high surface dose is evident for smallerdistance from the tray, so at least 25cm of skin shadow tray distance for 10MV X-ray and 20cm for Co-60 are desirable. 3. Utilization of either bolus for treatment field or electron boost should be considered in treatmentof superificial nodal disease. 4. A tray using an intermediate or high z No. filter can be reduced the surfacedose significantly.
Polymethyl Methacrylate
;
Silver Sulfadiazine
;
Skin
2.Early Diagnosis of Alzheimer's Disease Using Neuroimaging: Focus on Recent MRI and PET Studies.
Journal of Korean Geriatric Psychiatry 2008;12(1):11-16
Alzheimer's disease (AD) is the most common form of dementia. Because any antidementia treatment is not likely to reverse existing neuronal damage but rather to slow disease progression, early diagnosis is an important approach to identifying candidates for antidementia drug applications before the dementing process causes permanent brain damage. Neuroimaging could be the best alternative to pathologic confirmation of AD with biopsy that is invasive to subjects or post-mortem evaluation. In this manuscript, author summarized recent studies for early diagnosis of AD using neuroimaging techniques that have relatively high spatial resolution of regional volumetry using three dimensional magnetic resonance imaging (MRI), Fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET), Diffusion tensor imaging, and PET imaging of Alzheimer pathology with ligand. Moreover, author comments the future direction for early diagnosis of AD using neuroimaging.
Alzheimer Disease
;
Biopsy
;
Brain
;
Dementia
;
Diffusion Tensor Imaging
;
Disease Progression
;
Early Diagnosis
;
Magnetic Resonance Imaging
;
Neuroimaging
;
Neurons
;
Positron-Emission Tomography
3.Early Detection Program Development of Amnestic Mild Cognitive Impairment in the Community : Preliminary Study.
Journal of Korean Geriatric Psychiatry 2018;22(2):41-46
OBJECTIVE: Mild cognitive impairment (MCI) has high conversion risk to dementia. However, it is not easy to detect amnestic MCI patient early in the community. This study aimed to evaluate the three-stage design for early detection of amnestic MCI in the community. METHODS: Overall 4,385 persons participated who were already registered with Mini Mental Status Examination (MMSE) evaluation. It was conducted in Nam-Gu district, one of the 5 districts of Gwangju, Korea from Jan 1, 2017 to May 31, 2017. We first screened them applying inclusion criteria of over 5-year education and age, gender, education adjusted norm based MMSE Z score between −1.5 and 0. Second stage assessments were done by telephone interviews with asking subjective memory complaints and 5 words list recall tests. And 3rd stage evaluation of neuropsychological tests and clinical interview with visit were performed. RESULTS: We screened 456 of the 4,385 persons and 2nd stage included 51 of the 211 participants telephone interview completed. Twenty-four individuals visited clinic center for 3rd stage evaluation. We finally diagnosed 17 MCI including 16 amnestic MCI and 1 non-amnestic MCI. CONCLUSION: Our three-stage evaluation detected 16 amnestic MCI patients of the 4,385 community dwelling persons with primary screening of MMSE. Our study suggests that this three-stage performance could be effective for early detection of amnestic MCI in large sample community.
Dementia
;
Education
;
Gwangju
;
Humans
;
Independent Living
;
Interviews as Topic
;
Korea
;
Mass Screening
;
Memory
;
Mild Cognitive Impairment*
;
Neuropsychological Tests
;
Program Development*
4.Early Detection of Mild Cognitive Impairment Using Visual Immediate Recall Test in the Community
Journal of Korean Geriatric Psychiatry 2021;25(1):8-13
Objective:
Mild cognitive impairment (MCI) is transitional state between cognitively normal and dementia. It is not easy to detect MCI patient early in the community. This study aimed to detect MCI early performing learning memory tests of neuropsychological test domains in the community sample.
Methods:
Overall 7,307 individuals were already registered with Korean version of Mini-Mental Status Examination for Dementia Screening (MMSE-DS) evaluation. It was conducted across all 5 districts of Gwangju, Republic of Korea from April 1, 2020 toSeptember 30, 2020. As first step, we screened them applying inclusion criteria of age, sex, education adjusted norm based MMSE Z score between -1.5 and 0, and MMSE delayed recall score less than 2. And second assessments of neuropsychological tests and clinical diagnosis with visit were performed. We examined whether verbal and constructional learning memory tests can improve the detection of MCI by receiver operating curve (ROC) analysis.
Results:
Clinical diagnosis finally defined 100 amnestic MCI, 8 non-amnestic MCI and 6 cognitively normal (CN). Visual im-mediate and delayed recall test had the highest ROC overall accuracy of 79.2% (95% confidence interval 67.8-90.6%) differentiating MCI from CN.
Conclusion
Our study suggests that visual immediate recall test might be time saving and cost-effective in addition to accuracy to early detect MCI in the community.
5.Early Detection of Mild Cognitive Impairment Using Visual Immediate Recall Test in the Community
Journal of Korean Geriatric Psychiatry 2021;25(1):8-13
Objective:
Mild cognitive impairment (MCI) is transitional state between cognitively normal and dementia. It is not easy to detect MCI patient early in the community. This study aimed to detect MCI early performing learning memory tests of neuropsychological test domains in the community sample.
Methods:
Overall 7,307 individuals were already registered with Korean version of Mini-Mental Status Examination for Dementia Screening (MMSE-DS) evaluation. It was conducted across all 5 districts of Gwangju, Republic of Korea from April 1, 2020 toSeptember 30, 2020. As first step, we screened them applying inclusion criteria of age, sex, education adjusted norm based MMSE Z score between -1.5 and 0, and MMSE delayed recall score less than 2. And second assessments of neuropsychological tests and clinical diagnosis with visit were performed. We examined whether verbal and constructional learning memory tests can improve the detection of MCI by receiver operating curve (ROC) analysis.
Results:
Clinical diagnosis finally defined 100 amnestic MCI, 8 non-amnestic MCI and 6 cognitively normal (CN). Visual im-mediate and delayed recall test had the highest ROC overall accuracy of 79.2% (95% confidence interval 67.8-90.6%) differentiating MCI from CN.
Conclusion
Our study suggests that visual immediate recall test might be time saving and cost-effective in addition to accuracy to early detect MCI in the community.
6.A Study on the Correlation Between Subjective and Objective Scales in the Evaluation of Depressive Symptoms for the Elderly
Journal of Korean Geriatric Psychiatry 2023;27(1):23-29
Objective:
The aim of this study was to investigate the correlation between subjective and objective depression rating scale for the elderly with depressive symptoms.
Methods:
Thirty three outpatients aged more than 55 with depressive symptoms were assessed with the Patient Health Questionnare-9 (PHQ-9) and the Montgomery-Asberg Depression Rating Scale (MADRS). Similar items from each scale were paired to investigate their correlations. The level of agreement between the PHQ-9 and the MADRS was also assessed for subjects by using discrepancy-score.
Results:
Correlation between total scores of the PHQ-9 and the MADRS was significant (r=0.85, p<0.001). There were signifi-cant correlations between the paired items except for the item about volition. These results were the same in the group whose total education years are 7 or more. However, in the group whose total education years are 6 or less, there was no significant corre-lation between the paired items about sleep, concentration and volition.
Conclusion
These results demonstrate that using the PHQ-9 in elderly patients is reliable and education level might be considered when interpreting the scale.
7.The Role of Astrocyte Related to Early Diagnosis of Alzheimer’s Disease Dementia
Journal of Korean Geriatric Psychiatry 2024;28(1):1-6
Astrocyte occupies 20%-40% of all glial cells in human central nervous system (CNS) and is important regulator of CNS inflam-matory response. Astrocytes are responsible for controlling neuronal and synaptic homeostasis and playing a critical role in the maintenance of redox status. Reactive astrogliosis, astrocyte remodeling, clasmatodendrosis, and paralysis are related to Alzheimer’s disease dementia (AD). Various astrocyte biomarkers in AD have been applied. Regarding positron emission tomography imaging, radioisotopes such as [11C]-deuterium-L-deprenyl, [18F]-(S)-(2-methylpyrid-5-yl)-6-[(3-fluoro-2-hydroxy)propoxy]quinoline, [11C]-(2-(4,5-dihydro-1H-imidazol-2-yl)-1-methyl-1H-indole) have been proposed for surrogate markers of astrogliosis. There is also now a steadily growing interest in GFAP (glial fibrillary acidic protein) and S100 as cerebrospinal fluid and blood markers. In the fu-ture, early intervention related to reactive astrogliosis would make a clue for the early diagnosis and treatment of Alzheimer’s disease.
8.Comparison of Two Multi-Step Programs for Early Detection of Amnestic Mild Cognitive Impairment in the Community
Journal of Korean Geriatric Psychiatry 2020;24(1):10-16
Objective:
Amnestic mild cognitive impairment (aMCI) has high conversion risk to dementia. However, it is not easy to detect aMCI patient early in the community. This study aimed to compare two-step and three-step program for early detection of aMCI in the community.
Methods:
Overall 5,155 persons participated who were already registered with Korean version of Mini-Mental Status Examination for Dementia Screening (MMSE-DS) evaluation. It was conducted across 5 all districts of Gwangju, Republic of Korea from Jan 1, 2018 to March 31, 2018. As first step, we screened them applying inclusion criteria of age, sex, education adjusted norm based MMSE Z score between -1.5 and 0. Second evaluations which are not included in two-step program, were done by telephone interviews with asking subjective memory complaints and 5 word lists recall tests. And third assessments of neuropsychological tests and clinical diagnosis with visit were performed. Author compared two-step program and three-step program for aMCI diagnostic rate.
Results:
Two multi-step programs had no significant difference on aMCI diagnostic rate (p=0.81).
Conclusion
Our study suggests that two multi-step programs are similar for early detection of aMCI in the community.
9.Development of Exercise-Cognitive Cooking Convergence Program for Mild Cognitive Impairment: Preliminary Study
Journal of Korean Geriatric Psychiatry 2020;24(2):75-89
Objective:
Mild cognitive impairment (MCI) is transition state between cognitively normal and Alzheimer’s disease (AD) dementia. Physical exercise (PE) and cognitive training (CT) are known to have effect on risk factor reduction on AD prevalence.This study aimed to explore combined PE and CT, named as Exercise-Cognitive Cooking Program (ECCP) influencing on cog-nition, physical function, and cerebral cortical thickness or volume in MCI subjects.
Methods:
Eleven MCI patients participated who were randomized into experimental group (EXP, n=5) and control group (CTR, n=6). EXP subjects were given ECCP sessions, 3 times a week for 6 months. And CTR participants had regular daily activity similar before. Baseline and follow-up assessments of neuropsychological tests, physical function, and brain MRI were performed for all subjects.
Results:
There were no significant difference between EXP and CTR in baseline, follow-up, and differences between two as-sessments. However, CTR had significant fasting blood sugar increase (effect size, ES=0.8; p=0.03) and systolic/diastolic blood pressure decrease (ES=0.7, p=0.04; ES=0.6, p=0.04). EXP showed significant decrease of trace length and velocity in Romberg test (ES=1.0, p=0.04; ES=1.0, p=0.04), and increase of chair stand times in 30 seconds (ES=1.1, p=0.04). MRI results showed that CTR had significantly decreased cortical thickness in right precuneus (ES=0.5, p=0.04) and decreased volume in bilateral inferior parietal and cuneus (ES=0.5, p=0.04; ES=0.2, p=0.04).
Conclusion
This preliminary study suggest that ECCP for 6 months might have possibility of preventive effect on MCI progression to AD.
10.Structural MRI and Amyloid PET Imaging for Prediction of Conversion to Alzheimer's Disease in Patients with Mild Cognitive Impairment: A Meta-Analysis.
Eun Hyun SEO ; Woon Yeong PARK ; IL Han CHOO
Psychiatry Investigation 2017;14(2):205-215
OBJECTIVE: The aim of this study was to explore the prognostic values of biomarkers of neurodegeneration as measured by magnetic resonance imaging (MRI) and amyloid burden as measured by amyloid positron emission tomography (PET) in predicting conversion to Alzheimer's disease (AD) in patients with mild cognitive impairment (MCI). METHODS: PubMed and EMBASE databases were searched for structural MRI or amyloid PET imaging studies published between January 2000 and July 2014 that reported conversion to AD in patients with MCI. Means and standard deviations or individual numbers of biomarkers with positive or negative status at baseline and corresponding numbers of patients who had progressed to AD at follow-up were retrieved from each study. The effect size of each biomarker was expressed as Hedges's g. RESULTS: Twenty-four MRI studies and 8 amyloid PET imaging studies were retrieved. 674 of the 1741 participants (39%) developed AD. The effect size for predicting conversion to AD was 0.770 [95% confidence interval (CI) 0.607–0.934] for across MRI and 1.316 (95% CI 0.920–1.412) for amyloid PET imaging (p<0.001). The effect size was 1.256 (95% CI 0.902–1.609) for entorhinal cortex volume from MRI. CONCLUSION: Our study suggests that volumetric MRI measurement may be useful for the early detection of AD.
Alzheimer Disease*
;
Amyloid*
;
Biomarkers
;
Entorhinal Cortex
;
Follow-Up Studies
;
Humans
;
Magnetic Resonance Imaging*
;
Mild Cognitive Impairment*
;
Positron-Emission Tomography