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The main goal was to evaluate effectiveness of a modified TSE sequence compared with DIR (double inversion recovery) sequence in acquisition of fast flow brain vessel images using signal void effect. 32 healthy volunteers (10 men and 22 women; mean age of 31 years; ranging between 28-43 years) who underwent black blood DIR sequence (group A) and the modified TSE sequence (group B) were enrolled in our study. Signal to Noise Ratio (SNR) and Contrast to Noise Ratio (CNR) of the internal carotid arteries’ lumen were compared in T1 and T2 weighted images for both group A and B. The images obtained from group B showed lower SNR values in internal carotid artery than the group A in both of the T1 and T2 weighted images (11.49% and 13.66% respectively). While the CNR values were higher in the group B than the group A in both of the T1 and T2 weighted images (8.69% and 7.55 % respectively). The qualitative score of all categories were not significantly different between the two groups. Furthermore approximately 49% of the total scan time was reduced from group B. Our study is to shorten the scanning time and minimize the inconveniences of the patients in acquisition of the black blood images of brain by using the signal void effect in the modified TSE technique while keeping the diagnostic value of the test.

ObjectivesTo investigate the association between zolpidem prescription and suicide attempts in people with depressionMethodsA nationwide, population-based electronic medical records database from the Health Insurance Review & Assessment Service of South was used to investigate the incidence rate ratios (IRRs) of suicide attempts and probable suicide attempts in people with depression before and after zolpidem prescription using self-controlled case series design.ResultsIn a total of 445 people who attempted suicide and 23 141 people who attempted probable suicide attempt, the IRRs of suicidal behavior during the risk periods before and after zolpidem prescription increased compared with those at the baseline. The IRRs gradually increased and peaked immediately before the prescription of zolpidem. The IRR was 70.06 (95% CI: 25.58–191.90) on day 2 before zolpidem prescription and 63.35 (95% CI: 22.99–174.59) on day 1 after zolpidem prescription in the suicide attempt group. The IRR was 24.07 (95% CI: 20.50–28.26) on the day before zolpidem prescription and 14.96 (95% CI: 12.21–18.34) on the day after zolpidem prescription in the probable suicide attempt group. The ratios declined eventually after zolpidem was prescribed.ConclusionsAlthough zolpidem prescription was associated with an increased risk of suicide attempts in people with depression, the risk increased and peaked immediately before zolpidem prescription. The risk declined gradually thereafter. This result indicates that the risk of suicide attempts increases at the time of zolpidem prescription. However, zolpidem prescription does not contribute to additional increase in the risk of suicide attempts.

Major depressive disorder (MDD) is a common psychiatric disorder and the leading cause of disability worldwide. However, current methods used to diagnose depression mainly rely on clinical interviews and self-reported scales of depressive symptoms, which lack objectivity and efficiency. To address this challenge, we present a machine learning approach to screen for MDD using electrodermal activity (EDA). Participants included 30 patients with MDD and 37 healthy controls. Their EDA was measured during five experimental phases consisted of baseline, mental arithmetic task, recovery from the stress task, relaxation task, and recovery from the relaxation task, which elicited multiple alterations in autonomic activity. Selected EDA features were extracted from each phase, and differential EDA features between two distinct phases were evaluated. By using these features as input data and performing feature selection with SVM-RFE, 74% accuracy, 74% sensitivity, and 71% specificity could be achieved by our decision tree classifier. The most relevant features selected by SVM-RFE included differential EDA features and features from the stress and relaxation tasks. These findings suggest that automatic detection of depression based on EDA features is feasible and that monitoring changes in physiological signal when a subject is experiencing autonomic arousal and recovery may enhance discrimination power.

Objective Suicide is the leading cause of death in 10-39-year-olds in South Korea, and the second highest rate among the OECD countries. However, few studies have investigated the particularity of completed suicide in South Korea. Methods Study subjects consisted of 2,838 suicide cases and 56,758 age and sex matched living controls from a national representative sample of 1,025,340 South Koreans. They were obtained from the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC) with follow-up up to 12 years. We obtained information on primary diagnosis of any ICD-10 disorder along with suicide cases during their lifetime. Results Among ICD-10 disorders, depression was the most common disorder (19.10%, n=542), found in victims of completed suicides except for common medical disorders such as hypertensive crisis, respiratory tract infection or arthropathies. After adjusting for sex, age, economic status, disability, and disorders, schizophrenia showed the strongest association with suicide (AOR: 28.56, 95% CI: 19.58-41.66) among all ICD-10 disorders, followed by psoriasis, multiple body injury, epilepsy, sleep disorder, depression, and bipolar disorder. For age groups, ≤19 years was associated with anxiety disorder (AOR=80.65, 95% CI: 13.33-487.93), 20-34 years with epilepsy (AOR=134.92, 95% CI: 33.69-540.37), both 35-49 years (AOR=108.57, 95% CI: 37.17-317.09) and 50-65 years (AOR=189.41 95% CI: 26.59-1349.31), with schizophrenia, and >65 years (AOR=44.7, 95% CI: 8.93-223.63) with psoriasis. Conclusion Psychiatric and physical disorders carried greatly increased risks and numbers of suicides in South Korea. Schizophrenia was the strongest risk factor, especially 35-65 years, and depression was the most common in suicide victims among ICD-10 disorders in South Korea.

Background: To investigate the neurobiological evidence supporting the adaptogenic effects of Korean Red Ginseng in reducing the harmful consequences of stress using a double-blind, placebo-controlled trial. Method: Sixty-three subjects with high stress levels were randomized to receive an orally administered, double-blind, 6-week treatment with Korean Red Ginseng (n = 32) or placebo (n = 31). All participants underwent a comprehensive psychological evaluation using Beck Depression Inventory and Stress Response Inventory, cognitive evaluation using the continuous performance test, biological evaluation by measuring blood levels of lipids, catecholamines, inflammation markers, and heart rate variability at baseline and after 6 weeks. Results: At baseline, both groups showed no significant differences in age, sex, years of education, Beck Depression Inventory, and Stress Response Inventory. After 6 weeks, triglyceride levels were significantly increased within the normal limit in theKorean Red Ginseng group (F = 4.11, p = 0.048), and the epinephrine level was decreased in this group (F = 4,35, p = 0.043). The triglyceride increase was significantly associated with epinephrine decrease (B = −0.087, p = 0.041), suggesting that Korean Red Ginseng may stabilize the sympathetic nervous system. In addition, we detected a significant group by time effect in the visually controlled continuous performance test, suggesting positive effects of Korean Red Ginseng on cognition. Conclusion: Korean Red Ginseng might help to stabilize the sympathetic nervous system and improve cognition in individuals with high stress. Keywords: Adaptogenic effect, Epinephrine, Korean Red Ginseng, Stress management, Triglyceride

Regardless of categorical diagnosis, many psychiatric patients suffer from sudden attack of fear or intense anxiety. In this study, we defined anxiety attacks to refer to these phenomena and investigated their association with depression and suicide attempts. A total of 12,532 adults randomly selected population through the one-person-per-household method completed a face-to-face interview using the Korean version of Composite International Diagnostic Interview (K-CIDI). A total of 5.88% reported to have experienced anxiety attacks. Among them, 46.5% reported to have experienced anxiety attacks without life-threatening situations. ‘Anxiety attacks’ group reported more suicidal ideation, plan, and attempts, which were even higher frequencies in ‘anxiety attacks without life-threatening situations’ group than ‘anxiety attacks only with life-threatening situations’ group and showed stronger association with lifetime suicide attempts when it had comorbid major depressive disorder (MDD) (AOR = 9.69, 95%CI 5.90–15.90), compared with ‘never’ group. There was no association between each symptom of patients with anxiety attacks and their lifetime suicide attempt. In conclusion, the finding suggests that there are as many individuals who experience anxiety attacks without life-threatening situations as those with life-threatening situations. And anxiety attacks appear to be relevant to an increased risk of suicide attempt, especially without life-threatening situations and with comorbid MDD.

In this study, a susceptibility weighted image (SWI) showed a wrapped phase and a non-uniformity of the rapid susceptibility difference. Consequently, the bandwidth limits at low frequency were improved by applying HPF. From November 2013 to March 2014, a three-dimensional SWI was obtained from patients and compared with the existing images and HPF phase images. The maximum and minimum signal intensity differences and non-uniformity were analyzed. As a result, a high pass filter before and after applying the maximum and minimum of the signal intensity difference was decreased by 274.16% (498.98), and the non-uniformity was decreased by 439.55% (19.83). After applying the HPF, a comparison with the existing phase images revealed the HPF phase images to have high signal and image uniformity of the SWI image. A high pass filter method can effectively remove the non-uniformity and improve the overall image quality.

This study was conducted to minimize the imaging distortion by reducing the differences in susceptibility between the tissue and air surrounding it while performing a thyroid diffusion imaging procedure. The study group was composed of 23 healthy adults. Thyroids with many distortions near the air, larynx, and trachea were chosen to test and evaluate the diffusion imaging difference between before and after an application of silicon. As a result, there was reduced distortion with silicon application, and the differences decreased from 30% to 10%. According to One-way ANOVA and Duncan's post-hoc test, there were no significant differences between imaging with a silicon application and T2 imaging of the surface area, which was the standard image. In conclusion, this study presented a radical improvement in reducing the distortions in imaging by compensating for an uneven tissue surface near air without affecting the magnetic resonance contrast and complicating the imaging processes.

The aim of this study was provide basic information and establish the criteria in radiation therapy planningby measuring the absorbed neutron dose of normal tissues and lesions according to the number of portals. From September 2013 to January 2014, 20 patients who were diagnosed with prostate cancer and were previously treated with radiation therapy were replanned retrospectively to measure the absorbed neutron dose distribution according to the number of portals. The absorbed neutron dose was measured in each of the 5, 7 and 9 portals using a 15 MV energy, which meant a therapeutic dose of 220 cGy. The optical stimulation luminescence dosimeter was separated by 20cm and 60cm away from the center of the field of view. As a result, the average radiation dose in the abdomenappeared to have a positive relationship with the number of portals, which was statistically significant (p

This research, used an contrast agent, which weighs about 1mmol/mL, of twice as much amount of gadolinum, per unit, for the test of magnetic-resonance shoulder arthrography. the reasearch which was carried out from January, of the year 2012 to August of the year 2013. consisted, of target of 41, patients including 20 ones, of whom an original, contrast agent of amount of 0.5mmol/mL, 21, ones of whom, a new, of amount of 1mmol/mL was used on, were the test target, in order to figure out the differences, according to the amount of gadolinum, according to the test results, the SNR of the contrast agent, of amount of 1mmol/mL, which is of high amount of gadolinum, was noticeably higher than the one of amount of 0.5mmol/mL(the percentage of joint space 38.01%, the supraspinous muscle 8.40%, head of humerus 12.78%). and CNR of the contrast agent, of amount of 1mmol/mL, which is of high amount of gadolinum, was higher than the one of amount of 0.5mmol/mL(the percentage of joint space and supraspinous muscle 48.96%, the one of joint space and head of humerus 42.00%). In conclusion, one of the methods of increasing the reducing effect of T1, is to use contrast agent of amount of 1mmol/mL, in order to increase the reducing effect of T1, acquire the visual of high testing quality. Key Words : Gadolium content, 1mmol/mL MR contrast agents, MR arthrography, Direct MR arthrography, Shoulder arthrography

Background Major depressive disorder (MDD) is one of the leading causes of disability; however, current MDD diagnosis methods lack an objective assessment of depressive symptoms. Here, a machine learning approach to separate MDD patients from healthy controls was developed based on linear and nonlinear heart rate variability (HRV), which reflects the autonomic cardiovascular regulation. Methods HRV data were collected from 37 MDD patients and 41 healthy controls during five 5-min experimental phases: the baseline, a mental stress task, stress recovery, a relaxation task, and relaxation task recovery. The experimental protocol was designed to assess the autonomic responses to stress and recovery. Twenty HRV indices were extracted from each phase, and a total of 100 features were used for classification using a support vector machine (SVM). SVM-recursive feature elimination (RFE) and statistical filter were employed to perform feature selection. Results We achieved 74.4% accuracy, 73% sensitivity, and 75.6% specificity with two optimal features selected by SVM-RFE, which were extracted from the stress task recovery and mental stress phases. Classification performance worsened when individual phases were used separately as input data, compared to when all phases were included. The SVM-RFE using nonlinear and Poincare plot HRV features performed better than that using the linear indices and matched the best performance achieved by using all features. Conclusions We demonstrated the machine learning-based diagnosis of MDD using HRV analysis. Monitoring the changes in linear and nonlinear HRV features for various autonomic nervous system states can facilitate the more objective identification of MDD patients.

[Purpose] This study investigated the primary factors behind changes in depressive symptoms among stroke patients after 8 weeks of rehabilitation (physical, occupational, and cognitive therapy). [Methods] This study was conducted using a literature review, and electronic medical records from January, 2008 to December, 2009. Data were collected for 120 subjects with chronic stroke. [Results] Cardiac disorder, left-brain lesion, early-stage depression, activities of daily living, and cognitive function were significant predictors of the changes in depression in chronic stroke patients. [Conclusion] Post-stroke depression can be controlled by rehabilitation. Also, clinicians should comprehend and share the psychological and physical affliction, develop back-up programs, and make them comprehensively available to support the psychological and physical health of subjects with chronic stroke.

With the application of k-space trajectory in a different manner and analyzing the influence of noise and its direction, this study was conducted to obtain high-quality images with minimal influence of noise during an MRI examination for cerebrovascular disease, which has a low signal for imaging. To evaluate influence of the noise of different k-space trajectories, a linear Cartesian coordination trajectory and non-Cartesian coordination trajectory were applied to 38 people who had received a high-resolution MRI examination for the early detection of cerebrovascular disease. As a result, the non-Cartesian coordination trajectory showed a 43.32% lower signal of lumens in the internal carotid artery than a linear Cartesian coordination trajectory, and the noise level was also 50.19% lower in a non-Cartesian coordination trajectory. This result shows that noise occurs less in a non-Cartesian coordination trajectory than a linear Cartesian coordination trajectory, and a non-Cartesiancoordination trajectory is more effective in low-signal and low-resolution MRI examination. Therefore, when performing high-resolution MRI examination with a low-signal cerebrovascular system, the use of non-Cartesian coordination k-space trajectory will minimize the influence of noise and provide good images.

The purpose of this study is to maximize diagnositc usefulness with increasing signal to noise ratio(SNR) and contrast to noise ratio(CNR) by using a 1mmol/mL gadolinium contrast agent. From January 2012 to June 2013 fourty-seven patients were underwent the MRI scanning to investigate the contrast difference in gadolinium content. Twenty of the patients were injencted the commercial contrast agent containing 0.5mmol/mL gadolinium and the rest of them were injected the new contrast agent containing 1mmol/mL gadolinium called gadobutrol. We measured and evaluated each SNR and CNR of the hip joint space, iliopsoas muscle and femoral head. As a result, using the 1mmol/mL gadolinium contrast agent had the higher SNR results than using the 0.5mmol/mL agent(27% in the hip joint, 30.01% in the femoral head). Also CNR using the 1mmol/mL gadolinium agent was proved to be higher than that of using 0.5mmol/mL agent(28.31% in the ilopsoas muscle and 26.74% in the femoral head). Therefore, the contrast agent containing more gadolinium like 1mmol/mL used in this study is more effective to shorten T1 relaxation time, so it increases the signal intensity and CNR and furthermore maximizes diagnostic value. This study reports the usefulness of the 1mmol/mL contrast agent in the contrast-enhanced magnetic resonance hip arthrography for the first. Therefore, it can be considered to have an meaningful academic value as showing the method for increasing the diagnostic usefulness by using the 1mmol/mL contrast agent.

Measurements of CNR(Contrast to Noise Ratio) and SNR(Signal to Noise Ratio) of T-spine breathing technique (TBT) using spontaneous breathing and T-spine exhalation technique (TET) with full exhalation were carried out, and with which the more appropriate method was suggested. Both TBT and TET were examined in a sample of fifty-three patients who visit to our hospital for spinal disease from June 2012 to November 2012. All images were evaluated with CNR measured from the differences between the mean pixels and contrast density as setting ROI of spinous process, pedicle, vertebral body, intervertebral foramen, and intervertebral disk using Image J. SNR was measured with the mean pixels and the standard deviation as setting ROI of vertebral body using Image J. In CNR comparison and SNR comparison of TET and TBT, TBT was indicated as excellent in ROI of pedicle, vertebral body, intervertebral foramen and intervertebral disk, and statistical analysis were significant(p

The purpose of our study is to shorten the scanning time and minimize the inconveniences of the patients in acquisition of the black blood images using the signal void effect in the fast spin echo technique while keeping the diagnostic value of the test. Thirty-two consecutive patients who underwent black blood MR imaging were examed with additional double inversion recovery (DIR) sequence and the conventional fast spin echo (FSE) sequence. Signal to Noise Ratio (SNR) and Contrast to Noise Ratio (CNR) of the internal carotid arteries' lumen were compared in T1 and T2 weighted images to determine whether there are differences between the two techniques for depiction of the signal void effect inside the vessel wall. The FSE images showed lower SNR values than the DIR images in both of the T1 and T2 weighted images (11.49% and 13.66% respectively). While the CNR values were higher in the FSE images than in the DIR images in both of the T1 and T2 weighted images (8.69% and 7.55% respectively).There was no significant difference between the two techniques for either of the SNR or CNR (p>0.05, p>0.05 respectively). The DIR and the FSE images demonstrated almost identical imaging patterns. Therefore, it is anticipated that the use of FSE technique in acquisition of the black blood imaging could reduce the inconveniences of the patients during the scanning and minimize exam time while keeping the diagnostic value of the test.

This study attempt to develope and suggest a new, minimize side effects process for calculate a time to peak enhancement of contrast level by using blood flow instead of current mathematical process. We conducted a studies 127 patients who performed the CE MRA by using test-contrast inject way. We used measurements of a contrast inflow time and time to peak enhancement of contrast level of each cerebrovascular branch for similarity of witch cerebrovascular branch calculate a time to peak enhancement of contrast level by using blood flow in image compared with calculation a time to peak enhancement of contrast level by using current mathematical process after contrast enhancement. In this study, confidence interval were used if the variable is continuous variable; there is differences between 4 groups exist but in group 1, there is no difference with time in peak enhancement of contrast level by using mathematical method to inflow time in sinus sigmoideus. it was significant statistically, in addition there was significant low heterogeneity in Bland Altman plot. Thus, apply a new calculate a time to peak enhancement of contrast level by using blood flow method will minimize damage caused by side effect, maintain quality of image, easy and fast access. It should provide a space for the exchange of current calculate a time to peak enhancement of contrast level by using mathematical process.

The purpose of this study is to increase contrast to noise ratio(CNR) in myocardial viability test by using contrast agent which highly content gadolinium(1mmol/mL) maximizing diagnostic value. This research method that four hundred four patients were underwent the MRI scanning two hundred eighty four of them were injected commercial contrast media which have 0.5mmol/L and the rest of them were injected new contrast media(gadobutrol) which have 1mmol/mL of molarity to study the contrast difference depending on the molarity of the contrast agent signal intensities of normal ventricle and left ventricle were measured to compare and evaluate signal to noise ratio(SNR) and CNR of the images. As result, 1mmol/mL contrast agent showed higher SNR by 25.13% in myocardium and 30.74% in left ventricle. CNR was proved to be better in 1mmol/mL contrast agent by 31.29%. The results above were all statistically meaningful. Therefore, contrast agent contenting more gadolinium which was 1mmol/mL in this study, could more effectively shorten T1 relaxation time, increase the signal intensity and at the same time maximize CNR and diagnostic value. This study firstly report the usefulness of 1mmol/mL contrast agent in patients allegedly suffering cardiac diseases and it is considered to increase diagnostic value.

In this study was explored minimize side effects due to the additional injection of contrast medium and maintaining a high resolution imaging applied to the inspection and analysis of the contrast medium that affect the peak time biomechanics factors. Included 48 patients using the test bolus method, after measuring a patient's biomechanics factors of inspection before and during the test, correlation between contrast medium peak time and learn, matches the regression equation calculated and measured contrast medium peak time was assessed by the Bland Altman plot. Research result, inspections of SBP, HR contrast medium peak time and a significant negative correlation was, step 1, every increase, the contrast medium peak time significantly to -0.018 and -0.159 decreased, a fairly high concordance no difference between the two method. In conclusion, the regression equation using the existing methods, while maintaining excellent image quality that contrast medium is reduced to a patient, it can conclude that the alternative to the existing methods.

BOLD technique in functional MRI has to apply multiple stimulations. However as the stimulation time increases failure rates rise. In this study we are proposing proper number of stimulations through our experiments. Ten normal people underwent functional MRI hand motor sanning and the paradigms were designed from first to seventh stimulation. Under Philips Intera Achieva 3.0T MR system and Invivo cop`s Eloquence equipment, activation periods and rest periods were repeated ten times each, using BOLD EPI technique. Primary hand motor area stimulation and number of clusters, activation rates and number of activated clusters in and outside the region of interest were compared to each other. Number of clusters in region of interest was lower than others at second stimulation and became static from third stimulation. The stimulated ratios were elevated as the number of stimulations were increased but it was not proportional. Number of clusters outside the ROI became static from the third stimulation and started increasing from sixth stimulation. As results, given the activation ratios of ROI and out side the ROI, three times stimulation was the most appropriate because it does not affect accuracy, also decreasing the fatigue of patients by with the decreased scanning time.

MRI signals are significantly reduced by the magnetic field inhomogenity result from human body itself being consisted of various materials like air, fat, muscle, bone and blood vessels. In this study we used silicon which is tissue equivalent to compensate wound body shapes. Objects were eight adults who do not have any special symptoms. Feet were scanned because of their complicated structures and consequently signal reduction occurs a lot. Thirty images were acquired from the middle of arcus pedis longitudinalis including five distal phalanges parallel to the line connecting metatarsal bone and phalanges. SNR data from bones and soft tissues were compared before and after sticking silion between toes and paired t test was performed. It was came out that SNR data from bone and soft tissue were both significantly higher after applying silicon on both T1 and T2 weighted images and it was statistically meaningful having positive corelation. As a result, this study dramatically increases SNR without affecting object by increasing the object volume inside the surface coil.

This study is aimed at decreasing wrong diagnosis with corrected EF(Ejection Fraction) of 2D echo cardiography by analysing the physical time-resolution difference between Cine MRI and 2D echo cardiography and applying the corrected EF in 2D echocardiography. From February 2010 to December 2011, among the 110 patients who had undergone both 2D echo cardiography and cine MRI only 37 patient were selected suffering aortic valve regurgitation. ED,ES and SV were measured and EF was calculated in each system while normal ranges of Cine MRI and 2D echocardiography were compared to evauate misdiagnosis rate. The correlation of physical time resolution between 2D echocardiography and MRI was evaluated and the differences were corrected with linear regression coefficient which is derived from linear regression analysis. Blandt-Altman plot was used to evaluate the reliability of corrected 2D echo cardiography EF and compare the error among measured values. The values were compared with MRI normal range and misdiagnosis rate was measured again. As a result, misdiagnosis rates of physical time resolution were measured to be 32.4%(12people) before the correction of EF and 18.9%(7people) after the correction. Also, EF confirmed in Blandt-Altman plot were almost the same with MRI EF. In conclusion, when diagnosing aortic regurgitation disease, simply using 2D echocardiography can easily raise the misdiagnosis rates, therefore considering the MRI machine's physical merits, correcting the time resolution difference is important by calculating time resolution wrong diagnosis would decrease and it is considered to be useful in clinical circumstances

The purpose of this work is to know the validity of a new stimulation method in cognitive functional imaging using custom-designed images correspond to words or syllables improving the shortcomings of existing method using text. From March 2011 to May five Subjects in need of language related functional MRI scanning were selected and both of text stimulating method and image stimulating method sacanning were carried out three times each. Using 3.0T Philps MRI machine and Invivo Co's Eloquence system, data acquisition was performed with EPI-BOLD technique. Post processing was performed with SPM 99 while the activated signals were determined within 95 percent confidence level.The number of activation clusters and the activation ratio inside ROI were compared. As as result, all of the subject showed activation inside Broca area but it did not have statistical significance. In conclusion, the image sitimulation method has potential because image itself is a common means of recognition and it can be recognised easily even if there language barrier. This stimulation method can be applied to replacing the exising scanning method especially in the elderly, infants, foerigners who may not fully understand about the examination.