• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.2
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• pp.55-64
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• 2017

Purpose Recently, with the spread of SPECT/CT, various image correction methods can be applied quickly and accurately, which enabled us to expect quantitative accuracy as well as image quality improvement. Among them, the Collimator Detector Response(CDR) recovery is a correction method aiming at resolution recovery by compensating the blurring effect generated from the distance between the detector and the object. The purpose of this study is to find out quantitative change depending on the change in detection distance in SPECT/CT images with CDR recovery applied. Materials and Methods In order to find out the error of acquisition count depending on the change of detection distance, we set the detection distance according to the obit type as X, Y axis radius 30cm for circular, X, Y axis radius 21cm, 10cm for non-circular and non-circular auto(=auto body contouring, ABC_spacing limit 1cm) and applied reconstruction methods by dividing them into Astonish(3D-OSEM with CDR recovery) and OSEM(w/o CDR recovery) to find out the difference in activity recovery depending on the use of CDR recovery. At this time, attenuation correction, scatter correction, and decay correction were applied to all images. For the quantitative evaluation, calibration scan(cylindrical phantom, $^{99m}TcO_4$ 123.3 MBq, water 9293 ml) was obtained for the purpose of calculating the calibration factor(CF). For the phantom scan, a 50 cc syringe was filled with 31 ml of water and a phantom image was obtained by setting $^{99m}TcO_4$ 123.3 MBq. We set the VOI(volume of interest) in the entire volume of the syringe in the phantom image to measure total counts for each condition and obtained the error of the measured value against true value set by setting CF to check the quantitative accuracy according to the correction. Results The calculated CF was 154.28 (Bq/ml/cps/ml) and the measured values against true values in each conditional image were analyzed to be circular 87.5%, non-circular 90.1%, ABC 91.3% and circular 93.6%, non-circular 93.6%, ABC 93.9% in OSEM and Astonish, respectively. The closer the detection distance, the higher the accuracy of OSEM, and Astonish showed almost similar values regardless of distance. The error was the largest in the OSEM circular(-13.5%) and the smallest in the Astonish ABC(-6.1%). Conclusion SPECT/CT images showed that when the distance compensation is made through the application of CDR recovery, the detection distance shows almost the same quantitative accuracy as the proximity detection even under the distant condition, and accurate correction is possible without being affected by the change in detection distance.

• Journal of Korean Medical classics
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• v.4
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• pp.101-126
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• 1990

At early Cheong (淸) dynasty, in medical aspect by dependent on practical studying attitude that must found a theory only by an evidence, there had been a tendancy that hoped direct research of sages' mind-eye by escaping the theory of individual classes since Geum-Won (金-元) dynasty. Yoo Chang (喩昌), born in Man-Ryeok (萬曆) 12th year of Myung (明) dynasty (A.D.1583) and dead in Gang-Hee (康熙) 3rd year of Cheong (淸) dynasty (A.D.1664). The results were as follows after studying his practical idea of medicine. 1. Yoo Chang, by recognizing the ${\ll}$Sang-Han-Ro${\gg}$ has lost its true meaning after commented by Wang Hee (王熙), Lim Eog (林億), Seong Moo-I (成無巳), etc. according to Bang Yoo-Jip's (方有執) Chak-Gan-Jung-Jeong (錯簡重訂) theory, he diversified the protocal of ${\ll}$Sang-Han-Ro${\gg}$ 397 method and arranged under Six Meridian part. (六經) 2. The theory of Sam-Gang-Jeong-Rip (三綱鼎立) can be summerized Gye-Ji (桂枝) syndrome which is the case of Wind (風) has injured Wi (衛) stage, Ma-hwang (麻黃) syndrome which is the case of Cold (寒) has injured Yeong (榮) stage, Dae-Cheong-Ryong (大靑龍) syndrome which is the case both of Wind-Cold (風寒) has injured Yeong-Wi (榮衛) stage, and there has been Sam-Gang-Jeong-Rip theory by anterior medical practitioners already but the person who formally used its Sam-Gang-Jeong-Rip term is Yoo Chang. 3. Yoo Chang seized the On Byeng (溫病) by dividing three category and in Byon-Jeung-Si-Chi (辨證施治) he influenced to many aspect of establishment of later Byon-Jeung system On-Byong (溫病의 辨證體系) pertaining to Triple-Warmer by O-Dang (吳瑭) introducing Triple-Wanner Theory. (三焦理論) 4. At Chu-Jo-Ron (秋燥論) of ${\ll}$EUi-Moon-Beop-Ryo${\gg}$, while ${\ll}$Nae-Gyeong${\gg}$ describing if humidity injury Lung, then occur a disorder in it, Yoo Chang recognized that of au tuam when dryness injure Lung there occure a disorder is it so he insisted that at this case, must use Cheong-Joe-Goo-Pye method (淸操救肺法) withherbs, pertaing to Gam-Yoo-Ja-Yoon(甘柔滋潤性) property and he invented Cheong-Joe-Goo-Pye-Tang. (淸操救肺湯) 5. Yoo Chang', so called, Dae-Gi (大氣) indicates Yang-Gi (陽氣) of chest, he insisted that man's creation and every physiological activity depends on maintainence of Dae-Gi, and it integrate Yeong-Gi (榮氣), Wea-Gi (衛氣), Jong-Gi (宗氣), Jang-Boo-Ji-Gi (臟腑之氣), Gyeong-Rak-Ji-Gi. (經絡之氣) 6. Yoo Chang's expression about partical function and character of stomach, not only bolster its theory of historical physician's expression, that is stomach is. foundatness of postnatal period, but also it has corresponding aspect with modern medicine and clinic. 7. Yoo Chang emphasized "if one cure a disease, be must understood the character of disease first and use drugs later" (先議病 後用藥) phrase about of drug usage, and his theory of Geup-Rew-Man-Joo method (急流挽舟) and three therapy of Simple Ascite (單腹腸) are all unique opinion based upon this phrase mentioned above. 8. Yoo Chang's practical idea of medicine greatly influenced to Jang Ro (張璐), Hwang Won-A (黃元御), Oh Eui-Rak (吳儀洛), Joo Yang-Joon (周揚俊), etc. and theory of Sam-Gang-Jeng-Rip (三綱鼎立), Triple Warmer Theory of On Byong (溫疫의 三焦論治), Chu-Jo-Ron (秋燥論), Dae-Gi-Ron (大氣論) etc. became important object to student of Sang-Han (傷寒) and On-Byeng. (溫病) 9. Yoo Chang's Writings has more practical meaning than other physician's, especially, later the idea of Sang-Han (傷寒) and On-Byong (溫病) greatly contributed to development of Sang-Han theory and formation of On-Byong theory.