• 제목/요약/키워드: T1 recovery time

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T1, T2강조영상, FLAIR영상의 임상 적용 (T1-, T2-weighted, and FLAIR Imaging: Clinical Application)

  • 김재형
    • Investigative Magnetic Resonance Imaging
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    • 제13권1호
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    • pp.9-14
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    • 2009
  • T1, T2강조영상, FLAIR (fluid attenuated inversion recovery) 영상기법은 뇌 MRI의 가장 기본적인 영상기법들이다. T1강조영상은 짧은 TR과 짧은 TE를 이용한 스핀에코 기법으로서 조직의 T1이완시간의 차이를 신호 차이로 반영하는 기법이다. 짧은 TR을 사용하면 조직 간에 종축 자기화의 회복 정도가 크게 차이나게 되며 이를 신호에 반영하는 것이다. T2강조영상은 긴 TR과 긴 TE를 이용한 스핀에코 기법으로서 조직의 T2이완시간의 차이를 신호 차이로 반영하는 기법이다. 긴 TE을 사용하면 조직 간에 횡축 자기화의 붕괴가 크게 차이나게 되며 이를 신호에 반영하는 것이다. FLAIR는 180도 반전펄스를 먼저 가하는 반전회복 (inversion recovery) 기법의 일종으로서 뇌척수액의 신호를 억제하기 위하여 2500 msec 정도의 반전시간을 적용한다.

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견직물의 방추성에 관한 연구 I. 견방사직물을 중심으로 (Studies on the Wrinkle Resistance of the Silk Fabric I. Wrinkle Recovery behavior of spun.silk fabric)

  • 배두근;남중희;김종호
    • 한국잠사곤충학회지
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    • 제28권1호
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    • pp.61-65
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    • 1986
  • 견방견직물을 여러 가지 조건하에서 방추도를 측정하여 다음과 같은 결과를 얻었다. 1. 온도, 습도가 높아지면 방추도는 감소하며 습도의 영향이 온도의 영향보다 더 크게 작용한다. 2. 주름회복시간과 온도, 습도에 따른 방추도의 변화는 y=a+b ln T의 실험식으로 나타났고 회복시간의 경과에 따라 방추도는 증가하지만 300sec 이상에서는 평형상태에 도달했다. 3. 견직물과 화섬직물과 주름거동을 비교한 결과 견직물은 화섬직물에 비해 Voigt 모형에서의 K1값이 월등히 낮았다. 4. 조추시간에 따른 방추도 변화는 시간의 경과에 따라 점점 감소하지만 실험식에서 a값의 변화는 인정할 수 없었다. 5. 조추가중에 의한 방추도의 변화에 있어서도 동일한 결과를 얻었다.

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Quantitative Analysis of T1 Weighted Images due to Change in TI by Using the Inversion Recovery in 3.0T Brain MRI Examination

  • Han, Jung-Seok;Dong, Kyung-Rae;Chung, Woon-Kwan;Cho, Jae-Hwan;Shin, Jae-Woo;Kim, Young-Jae
    • Journal of Magnetics
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    • 제17권2호
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    • pp.158-162
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    • 2012
  • Although 3.0T magnetic resonance imaging (MRI) has the advantages of a higher signal to noise ratio (SNR) and contrast than 1.5T MRI, there are limitations on the contrast between white and grey matter because of the long T1 recovery time when T1 images are obtained using the Spin Echo Technique. To overcome this, T1 weighted images are obtained occasionally using the inversion recovery (IR) technique, which employs a relatively long TR. The aim of this study was to determine the optimal TI in a brain examination when a T1 weighted image is obtained using the IR technique. Eight participants (male: 7, female: 1, average age: $34{\pm}14.11$) with a normal diagnosis were targeted from February 18, 2012 to February 27, 2012, and the contrast between white and grey matter as well as the contrast to noise ratio (CNRs) in each participant were measured. The CNRs of white matter and grey matter were highest at TI = 600, 650, 750, 900, 1050 and 1100 ms when the TR was 1100, 1400, 1700, 2000, 2300 and 2600 ms, respectively. Therefore, as the TIs were $44.425{\pm}0.877%$ of the TRs in the TR range of 1400-2300 ms, the optimal T1 weighted images that describe the contrast between white and grey matter can be obtained if the TIs are compensated for with $44.425{\pm}0.877%$ of the TRs in the time of setting TIs.

흉부경락마사지가 충수돌기 절제술 환자의 마취 후 회복에 미치는 효과 (The Effect of Chest Meridian Massage on Post- Anesthetic Recovery of General Anesthesia Patients)

  • 이병엽;손경희
    • 성인간호학회지
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    • 제17권4호
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    • pp.612-621
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    • 2005
  • Purpose: This study aims at confirming the effects of the chest meridian massage on the post-anesthetic recovery of general anesthesia appendectomy patients. Method: The research was post-test designed as a nonequivalent control group among quasi-experiments tested. The data was collected from June 20, 2003 to October 14, 2003 at a hospital in P city. In the collected data, using SPSS Win 10.0 program, these general features were analyzed by real numbers and percentages; the homogeneity among variables by $X^2-test$ and t-test and the research hypothesis by the t-test. Result: Hypothesis 1; The experimental group receiving the treatment of the chest meridian massage will have a much higher post-anesthetic recovery score than that of the control group not receiving it was supported(t=2.544, p=.014). Hypothesis 2; The experimental group receiving the treatment of the chest meridian massage will have a much shorter time of stay in the recovery room than that of the control group not receiving it was supported(t=-4.919, p=.000). Conclusion: According to these results, it may be concluded that Chest Meridian Massage is effective in producing a higher level of post-anesthetic recovery score and helps appendectomy patients reduce the time of stay in the recovery room. Therefore the chest meridian massage can be considered as an intervention therapy for directly nursing general anesthesia appendectomy patients.

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Effects of adenosine receptor agonist on the rocuronium-induced neuromuscular block and sugammadex-induced recovery

  • Kim, Yong Beom;Lee, Sangseok;Choi, Hey Ran;In, Junyong;Chang, Young Jin;Kim, Ha Jung;Ro, Young Jin;Yang, Hong-Seuk
    • Korean Journal of Anesthesiology
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    • 제71권6호
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    • pp.476-482
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    • 2018
  • Background: Several types of receptors are found at neuromuscular presynaptic membranes. Presynaptic inhibitory $A_1$ and facilitatory $A_{2A}$ receptors mediate different modulatory functions on acetylcholine release. This study investigated whether adenosine $A_1$ receptor agonist contributes to the first twitch tension (T1) of train-of-four (TOF) stimulation depression and TOF fade during rocuronium-induced neuromuscular blockade, and sugammadex-induced recovery. Methods: Phrenic nerve-diaphragm tissues were obtained from 30 adult Sprague-Dawley rats. Each tissue specimen was randomly allocated to either control group or 2-chloroadenosine (CADO, $10{\mu}M$) group. One hour of reaction time was allowed before initiating main experimental data collection. Loading and boost doses of rocuronium were sequentially administered until > 95% depression of the T1 was achieved. After confirming that there was no T1 twitch tension response, 15 min of resting time was allowed, after which sugammadex was administered. Recovery profiles (T1, TOF ratio [TOFR], and recovery index) were collected for 1 h and compared between groups. Results: There were statistically significant differences on amount of rocuronium (actually used during experiment), TOFR changes during concentration-response of rocuronium (P = 0.04), and recovery profiles (P < 0.01) of CADO group comparing with the control group. However, at the initial phase of this experiment, dose-response of rocuronium in each group demonstrated no statistically significant differences (P = 0.12). Conclusions: The adenosine $A_1$ receptor agonist (CADO) influenced the TOFR and the recovery profile. After activating adenosine receptor, sugammadex-induced recovery from rocuronium-induced neuromuscular block was delayed.

개에서 Tiletamine-Zolazepam 마취에 대한 Doxapram과 Yohimbine의 길항효과 (Antagonistic Effects of Doxapram and Yohimbine on Tiletamine-Zolazepam Anesthesia in Dogs)

  • 박명호;김명철
    • 한국임상수의학회지
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    • 제12권1호
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    • pp.799-818
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    • 1995
  • This study was performed to examine the general anesthetic efficacy of tiletamine-zolazepam, a mixture of phencyclidine-derived tiletamine and benzodiazepine-related zolazepam. The antagonistic activities of doxapram and yohimbine to the anesthetic effects of tiletamine-zolazepam were also studied. Thirty healthy mongrel dogs were divided into three groups (each of 10) twenty minutes after being anesthetized with tiletamine-zolazepam : T-Z-S group(tiletamine-zolazepam-saline), T-Z-D group (tiletamine -zolazepam-doxapram), T-Z-Y group (tiletamine-zolaz.pam-yohim bine). Various parameters wert evaluated in terms of the onset and recovery time of analgesia, respiration rates, hear rates, body temperature, electrocardiogram, blood chemistry, and lymphocyte blastogenesis. The results obtained through these experiment could be summarized as follows: 1. he anesthetic efficacy of tiletamine-zolazepam was considered desirable, with the onset time of anesthesia being as short as 0.23-0.24 minutes. 2. Both of the antagonistic effects of yohimbine and doxapram on the anesthesia induced by liletamine-zolazepan were evaluated statistically significant(p<0.05) as the recovery time was shortened from 39.3$\pm$4.9 min(T-Z-S group) to 25.3$\pm$2.9 nin(T-Z-Y group) and 29.9$\pm$8.8min(T-Z-D group), respectively. 3. Respiration rates were not changed by the treatments of both doxapram and yohimbine, with the only transient increase in the T-Z-D group. The changes in the respiration rate were not observed during the whole time course of the experiment. 4. Yohimbine(T-Z-Y group) increased the heart rate significantly from 30 minutes after the adminstration compared to the T-Z-S group and T-Z-D group (p<0.05). 5. The decreases in th, body temporature were observed from 30 minutes in the T-Z-S group(p<0.05) and 40 minutes in th, T-Z-D group(p<0.05), after the adminstration. On the other hand, there was no hypothermia in the T-Z-Y group. 6. In the all experimental groups of the T-Z-S, T-Z-D and T-Z-Y, there were no specific findings on the electrocardiograph incept slight shift to the tachycardia in all cases. 1. We could not find any differences in the blood chemistry between all experimental groups (T-Z-S, T-Z-D and T-Z-Y). 8. the inhibition of the lymphocyte blastogenesis shown in the T-Z-S with 3 hours decreasing and thereafter restoring to the normal values up to the point 5 hours were not occurred in the T-Z-D and T-Z-Y groups. With the above results, we could conclude that both doxapram and yohimbine can be clinically used as recovery agents towards anesthesia by tiletamine- zolazepam fi:on the efficacy point of view, but yohimbine is more recommendable in this case if considering the recovery time and lymphocyte blastogenesis.

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A Potential Diagnostic Pitfall in the Differentiation of Hemorrhagic and Fatty Lesions Using Short Inversion Time Inversion Recovery: a Case Report

  • Kim, Jee Hye;Kang, Woo Young;Cho, Bum Sang;Yi, Kyung Sik
    • Investigative Magnetic Resonance Imaging
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    • 제20권3호
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    • pp.181-184
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    • 2016
  • Short inversion time inversion recovery (STIR) is widely used for spinal magnetic resonance imaging (MRI) because the pulse sequence of STIR is insensitive to magnetic field inhomogeneity and can be used to scan a large field of view. In this case report, we present a case of spinal epidural hematoma with unexpected signal decrease on a STIR image. The MRI showed an epidural mass that appeared with high signal intensity on both T1- and T2-weighted images. However, a signal decrease was encountered on the STIR image. This nonspecific decrease of signal in tissue with a short T1 relaxation time that is similar to that of fat (i.e., hemorrhage) could lead to a diagnostic pitfall; one could falsely diagnose this decrease of signal as fat instead of hemorrhage. Awareness of the nonselective signal suppression achieved with STIR pulse sequences may avert an erroneous diagnosis in image interpretation.

석창포원지탕(石菖蒲遠志湯)의 Alcoholism에서의 간위(肝胃) 치유 및 학습능력향상 효과 (Effects of the Seokchangpo-Wonji-Tang on Recovery from Disorder of Stomach, Liver and Mental-faculty in Alcoholism)

  • 박영서;임종필
    • 동의생리병리학회지
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    • 제19권5호
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    • pp.1292-1295
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    • 2005
  • Effects of the Seokchangpo-Wonji-Tang on recovery from disorder of stomach, liver and mental-faculty in alcoholism were studied using male Sprague-Dawley rats. The rats were assigned into 4 groups; normal, control and Seokchangpo-Wonji-Tang(SWT) group. Control group administered ethanol(25 v/v %) at a dose 3g/kg, while SWT group administered 50mg/kg of SWT 30min before treating same dose of ethanol as control group for 10 days, orally. The gastric ulceration and also GOT and GPT activities in rats were checked, and all groups were subjected to trials of straight channel on the 1st day and to those of multiple T-maze during the following 3 days. The gastric ulceration, GOT and GPT activities were increased in control group, but decreased in SWT group significantly. The time required in normal group for the straight channel of the 2nd and 3rd trials was significantly shorter than that of the 1 st, while the control group showed no significance. In the time required for the multiple T-maze trials, the control group showed no significance. But in the straight or T-maze trials, the SWT group showed significant decrease in the time required against the control group.

복구 성능 향상을 위한 플래시 메모리 관리 기법 (A Flash Memory Management Method for Enhancing the Recovery Performance)

  • 박송화;이정훈;조성우;김상현
    • 대한임베디드공학회논문지
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    • 제13권5호
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    • pp.235-243
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    • 2018
  • NAND flash memory has been widely used for embedded systems as storage device and the flash memory file systems such as JFFS2, YAFFS/YAFFS2 have been adopted by these embedded systems. The flash memory file systems provide the high performance and overcome the limitations of flash memory. However, these file systems don't solve the slow mount time problem when a sudden power failure happens. In this paper, we proposed a flash memory management method for enhancing the recovery performance. The proposed method manages the flash memory block type and stores the block type information at recovery image block. When file operations are occurred, our method stores the file information at the metadata block before and after the file operation. When mounting the flash memory, our method only scans the recovery image blocks and metadata blocks. The proposed method reduces the mount time by seeking the metadata block locations fast by using the recovery image blocks. We implemented the proposed method and evaluation results show that our method reduces the mount time 13 ~ 46 % compared with YAFFS2.

Evaluation of Modified Turbo Spin Echo Technique Compared with Double Inversion Recovery Technique in Acquisition of Black Blood Brain Vessel Image

  • Choi, Kwan-Woo;Lee, Ho-Beom;Na, Sa-Ra;Son, Soon-Yong
    • Journal of Magnetics
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    • 제21권1호
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    • pp.148-152
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    • 2016
  • 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.