• Title/Summary/Keyword: Evaluation method

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A study on dose attenuation in bone density when TBI using diode detector and TLD (전신방사선조사(TBI)시 다이오드 측정기(Diode detector) 및 열형광선량계(TLD)를 이용한 골조직 선량감쇄에 대한 고찰)

  • IM Hyun Sil;Lee Jung Jin;Jang Ahn Ki;Kim Wan Seon
    • The Journal of Korean Society for Radiation Therapy
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    • v.15 no.1
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    • pp.67-77
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    • 2003
  • I. Purpose Uniform dose distribution of the whole body is essential factor for the total body irradiation(TBI). In order to achieved this goal, we used to compensation filter to compensate body contour irregularity and thickness differences. But we can not compensate components of body, namely lung or bone. The purpose of this study is evaluation of dose attenuation in bone tissue when TBI using diode detectors and TLD system. II. Materials and Methods The object of this study were 5 patients who undergo TBI at our hospital. Dosimetry system were diode detectors and TLD system. Treatment method was bilateral and delivered 10MV X-ray from linear accelerator. Measurement points were head, neck, pelvis, knees and ankles. TLD used two patients and diode detectors used three patients. III. Results Results are as followed. All measured dose value were normalized skin dose. TLD dosimetry : Measured skin dose of head, neck, pelvis, knees and ankles were $92.78{\pm}3.3,\;104.34{\pm}2.3,\;98.03{\pm}1.4,\;99.9{\pm}2.53,\;98.17{\pm}0.56$ respectably. Measured mid-depth dose of pelvis, knees and ankles were $86{\pm}1.82,\;93.24{\pm}2.53,\;91.50{\pm}2.84$ respectably. There were $6.67\%{\sim}11.65\%$ dose attenuation at mid-depth in pelvis, knees and ankles. Diode detector : Measured skin dose of head, neck, pelvis, knees and ankles were $95.23{\pm}1.18,\;98.33{\pm}0.6,\;93.5{\pm}1.5,\;87.3{\pm}1.5,\;86.90{\pm}1.16$ respectably. There were $4.53\%{\sim}12.6\%$ dose attenuation at mid-depth in pelvis, knees and ankles. IV. Conclusion We concluded that dose measurement with TLD or diode detector was inevitable when TBI treatment. Considered dose attenuation in bone tissue, We must have adequately deduction of compensator thickness that body portion involved bone tissue.

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Evaluation of Dose and Position Compensation of Parotid Gland Using CT On-rail System in Head-and-Neck Cancer (두경부 암환자 치료 시 CT On-rail System을 이용한 이하선의 위치 보정 및 선량 평가)

  • Jang, Hyeong-Jun;Im, Chung-Geun;Chun, Geum-Sung;Jeong, Il-Seon;Kim, Hoi-Nam
    • The Journal of Korean Society for Radiation Therapy
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    • v.20 no.2
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    • pp.83-89
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    • 2008
  • Purpose: The checking method of target and normal structure are used by MVCBCT, KVCBCT, CT On-rail System, Ultrasound in H&N cancer patient. In case of MVCT, the utilization of bone structure is valuable to check around tissue. But the utilization of soft tissue is not enough. The point of this paper is dose variation in movable parotid and changeable volume of H&N cancer patient of CT On-rail System. Materials and Methods: The object of H&N cancer patient is 5 in this hospital. The selected patient are scanned ARTISTE CT Vision (CT On-ral System) a triweekly. After CT scanning, tranfered coordinates are obtained by movable of parotid gland comparison with planning image. Checking for the changeable volume of parotid gland. A Obtained CT image are tranfered to the RTP System. So dose variation are checked by following changed volume. Results: The changes of target coordinate by the parotid gland movement are X: -0.4~0.4 cm, Y: -0.4~0.3 cm, Z: -0.3~0.3 cm. the volume of GTV is decreased to about 7.11%/week and then both parotid gland volume are shrinked about 4.81%/week (Lt), 2.91%/week (Rt). At the same time, each parotid gland are diminished in radiation dose as 3.66%/week (Lt), 2.01%/week. Conclusion: Images from CT on the rail System which are able to aquire the better quality images of soft tissue in Target area than MVCBCT. After replanning and dose redistribution by required images, It could gain not only the correction of the patient set-tup errors but exact dose distribution. Accordingly, the delivery of compensated dose, It makes that we could do Adaptive Targeting Radiotherapy and need Real Time Adaptive Targeting Radiotherapy by reduce beam delivary time.

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A Comparative Study on Image Quality of Breast Image Tests using ACR Phantom (ACR 팬텀을 이용한 시스템별 유방검사 영상의 비교 연구)

  • Hong, Dong-Hee;Jung, Hong-Ryang;Lim, Cheong-Hwan
    • Journal of radiological science and technology
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    • v.29 no.4
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    • pp.241-247
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    • 2006
  • Recently, interests and utilization on Computed Radiography(CR) and Digital Radiography(DR) tends to increase owing to an introduction of Picture Archiving and Communication System(PACS) and an accuracy control of special medical equipment for a breast imaging examination. This study was intended to compare and analyze a detector's imaging quality by each system to be used for the breast imaging examination by using ACR Phantom used at the accuracy control. As an evaluation method, a significance and reliability of image's value using the ACR Phantom was analyzed by using SPSS program. The results are followed. 1. For the fiber, there was 3.9 score in Screen-Film, 4.2 score in CR($50{\mu}m$), 3.2 score in CR($100{\mu}m$), and 4.2 score in DR. There was the high score in the order of CR($50{\mu}m$), DR, Screen-Film, and CR($100{\mu}m$)(P<0.05). 2. For the calcification, there was 2.7 score in Screen-Film, 2.5 score in CR($50{\mu}m$), 2.0 score in CR($100{\mu}m$), and 2.9 score in DR. There was the high score in the order of DR, Screen-Film, CR($50{\mu}m$), and CR($100{\mu}m$).(0.025(P<0.05). 3. For Mass, there was 3.8 score in Screen-Film, 3.8 score in CR($50{\mu}m$), 3.6 score in CR($100{\mu}m$), and 4.5 score in DR. There was the high score in the order of DR, CR($50{\mu}m$), Screen-Film, and CR($100{\mu}m$) (P<0.1). 4. As the total score, there was 10.4 score in Screen-Film, 10.6 score in CR($50{\mu}m$), 8.7 score in CR($100{\mu}m$), and 11.3 score in DR. There was the high score in the order of DR, $CR(50{\mu}m$), Screen-Film, and $CR(100{\mu}m$). As shown in the above results, it can be known that DR and Screen-Film System has higher image quality than CR. But, DR has unstability caused by element, and Screen-Film has the low image quality caused by artifact as disadvantages. When Dual-Side CR($50{\mu}m$) was used among CR systems which had the problem of low image quality, it was indicated that there was no difference with Screen-Film System. Because the radiation imaging examination tends to become digitalized, each system for the breast imaging examination will need to be developed and supplemented.

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Treatment of Contaminated Sediment for Water Quality Improvement of Small-scale Reservoir (소하천형 호수의 수질개선을 위한 퇴적저니 처리방안 연구)

  • 배우근;이창수;정진욱;최동호
    • Journal of Soil and Groundwater Environment
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    • v.7 no.4
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    • pp.31-39
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    • 2002
  • Pollutants from industry, mining, agriculture, and other sources have contaminated sediments in many surface water bodies. Sediment contamination poses a severe threat to human health and environment because many toxic contaminants that are barely detectable in the water column can accumulate in sediments at much higher levels. The purpose of this study was to make optimal treatment and disposal plan o( sediment for water quality improvement in small-scale resevoir based on an evaluation of degree of contamination. The degree of contamination were investigated for 23 samples of 9 site at different depth of sediment in small-scale J river. Results for analysis of contaminated sediments were observed that copper concentration of 4 samples were higher than the regulation of hazardous waste (3 mg/L) and that of all samples were exceeded soil pollution warning levels for agricultural areas. Lead and mercury concentration of all samples were detected below both regulations. Necessary of sediment dredge was evaluated for organic matter and nutrient through standard levels of Paldang lake and the lower Han river in Korea and Tokyo bay and Yokohama bay in Japan. The degree of contamination for organic matter and nutrient was not serious. Compared standard levels of Japan, America, and Canada for heavy metal, contaminated sediment was concluded as lowest effect level or limit of tolerance level because standard levels of America and Canada was established worst effect of benthic organisms. The optimal treatment method of sediment contained heavy metal was cement-based solidification/stabilization to prevent heavy metal leaching.

Pattern of Decrease of Prostate Specific Antigen after Radical Radiotherapy for the Prostate Cancer (전립선암 환자에서 방사선치료 루 전립선특이항원 농도 변화 양상)

  • Kim Bo-Kyoung;Park Suk Won;Ha Sung Whan
    • Radiation Oncology Journal
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    • v.17 no.2
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    • pp.136-140
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    • 1999
  • Purpose : Prostate specific antigen (PSA) is a useful tumor marker, which is widely used as a diagnostic index and predictor of both treatment and follow-up result in prostate cancer. A prospective analysis was carried out to obtain the period of PSA normalization and the half life of PSA and to analyze the factors influencing the period of PSA normalization. The PSA level was checked before and serially after radical radiotherapy. Materials and Method : Twen쇼 patients with clinically localized prostate cancer who underwent radical external beam radiotherapy were enrolled in this study. Accrual period was from April 1993 to May 1998. Median follow-up period was 20 months. Radiotherapy was given to whole pelvis followed by a boost to prostate. Dose range for the whole pelvis was from 45 Gy to 50 Gy and boost dose to prostate, from 14 Gy to 20 Gy. The post-irradiation PSA normal value was under 3.0 ng/ml. The physical examination and serum PSA level evaluation were performed at 3 month interval in the first one year, and then at every 4 to 6 months. Results : PSA value was normalized in nineteen patients (95%) within 12 months. The mean period of PSA normalization was 5.3 (${\pm}$2.7) months. The half life of PSA Of the nonfailing patients was 2.1 (${\pm}$0.9) month. The nadir PSA level Of the nonfailing Patients waS 0.8 (${\pm}$0.5) ng/ml. The period of PSA normalization had the positive correlation with pretreatment PSA level (R$^{2}$=0.468). The nadir PSA level had no definite positive correlation with the pretreatment PSA level (R$^{2}$=0.075). The half life of serum PSA level also had no definite correlation with pretreatment PSA level (R$^{2}$=0.029). Conclusion :The PSA level was mostly normalized within 8 months (85%). If it has not normalized within 12 months, we should consider the residual disease in prostate or distant metastasis. In 2 patients, the PSA level increased 6 months or 20 months before clinical disease was detected. So the serum PSA level can be used as early diagnostic indicator of treatment failure.

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Observation of Response to PPD Skin Test and Local Side Reactions at Multiple Inoculation Sites after Percutanous Inoculation with BCG Tokyo 172 Strain (경피용 건조 B.C.G. 백신(Tokyo 172주) 접종 후 국소 반응과 투베르쿨린 양전율에 관한 연구)

  • Lee, Jin Soo;Sohn, Young Mo
    • Pediatric Infection and Vaccine
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    • v.7 no.2
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    • pp.201-210
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    • 2000
  • Purpose : We observed response to PPD skin test and local side reactions among subjects who received inoculation with Tokyo 172 BCG strain by percutaneous method using multiple puncture device. Methods : 138 infants and young children were enrolled at Yongdong Severance Hospital and 7 private clinics. 5TU PPD skin test were performed at 4 months after inoculation. The local reactions at multiple puncture site were observed in 3 days, 4~6 weeks, 36 weeks, and 48 weeks after inoculations and physical check up was done for evaluation of lymphadenopathy. Results : During 48 weeks of observation period, 96 subjects among 138 who were enrolled were followed up completely with records of PPD skin test and observation of local side reactions, presenting with the photos. The size of the induration after 48 hours of PPD skin test, was less than 5mm in six subjects(6.3%), greater than 10mm in sixty seven subjects(70.0%) and greater than 12mm in forty six subjects(47.9%). All subjects showed inflammatory reaction and pustules at multiple puncture sites and only just small papules, ulcer and pustules remained 4-6 weeks later. Eight to twelve weeks later, all local inflammatory skin reactions disappeared with remaining crust. After 48 weeks, 4(4.2%) subjects showed no scar with only faint stain on the puncture site. More than 70% of subjects showed more than 10 faint pin-point scars on the sites. However, the size of scar was clearly smaller compared to that of intradermal inoculation. There were no cases of lymphadenopathy. Conclusion : We observed good immune response to 5TU PPD skin test among the infant and young children who were immunized with percutanous inoculation of Tokyo 172 BCG strain. We could not find any severe local scar at inoculation sites. A degree of satisfaction of the parents whose children received the percutaneous injection was very high.

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Clinicopathological evaluation of Childhood Henoch-$Sch{\ddot{o}}nlein$ Purpura(HSP) Nephritis with Nephrotic Syndrome (신증후군을 동반한 Henoch-$Sch{\ddot{o}}nlein$ 신염 환아의 임상병리 적 고찰)

  • Kang Hyeon-Ho;Yoon Kyung-Leem;Cho Byoung-Soo
    • Childhood Kidney Diseases
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    • v.4 no.2
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    • pp.111-119
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    • 2000
  • Purpose : Henoch-$Sch{\ddot{o}}nlein$ purpura(HSP) is a common pediatric discase presenting most frequently with skin, gastrointestinal, joint and renal manifestations. The prognosis of HSP is mainly determined by the involvement of the kidney, but prognostic markers have not been established. We evaluated the patients who have HSP nephritis with nephrotic syndrome. Method : Clinical manifestations and laboratory findings were observed and analyzed in 34 cases with HSP which were manifested by nephrotic syndrome hospitalized at Kyung Hee university Hospital during the period from Jan. 1990 to Dec. 1998. Results : 1) Male to female ratio was 1.3:1, and mean age at onset was 8.3 year. 2) Mean duration from symptom onset to renal biopsy was 10.5 weeks. 3) Proportion of patients presenting with acute nephritis was 32.4$\%$, gross hematuria 17.6$\%$, microscopic hematuria 50$\%$. 4) The findings of renal biopsy were 20 cases of grade II, 11 cases of grade III, 2 cases of grade I, 1 case of grade IV according to classification by ISKDC. 5) Patients with grade I were recovered with no residual defect, but patients with grade IV shows active renal disease(states C). Conclusion : Among the 디le patients with Henoch-$Sch{\ddot{o}}nlein$ purpura accompanying nephrotic syndrome, more aggressive treatment might be needed in patients showing crescents formation on renal biopsy. A prospective study will be needed to explore the progression of this disease.

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Analysis of $^{99m}Tc-ECD$ Brain SPECT images in Boys and Girls ADHD using Statistical Parametric Mapping(SPM) (통계적 파라미터지도 작성법(SPM)을 이용한 남여별 ADHD환자의 뇌 SPECT 영상비교분석)

  • Park, Soung-Ock;Kwon, Soo-Il
    • Journal of radiological science and technology
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    • v.27 no.3
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    • pp.31-41
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    • 2004
  • Attention deficit hyperactivity disorder(ADHD)is one of the most common psychiatric disorders in childhood, especially school age children and persisting into adult. ADHD is affected 7.6% in our children, Korea. and persisting into $15{\sim}20%$ in adult. And it is characterized by hyperactivity, inattention and impulsivity. Brain imaging is one of way to diagnosis for ADHD. Brain imaging studies may be provide information two types - structural and functional imaging. Structural and functional images of the brain play an important role in management of neurologic and psyciatric disorders. Brain SPECT, with perfusion imaging radiopharmaceuticals is one of the appropriate test to diagnosis of neurologic and psychiatric diseases. Ther are a few studies about separated analysis between boys and girls ADHD SPECT brain images. Selection of Probability level(P-value) is very important to determind the abnormalities when analysis a data by SPM. SPM is a statistical method used for image analysis and determine statistical different between two groups-normal and ADHD. Commonly used P-value is P<0.05 in statistical analysis. The purpose of this study is to evaluation of blood flow clusters distribution, between boys and girls ADHD. The number of normal boys are 8(6-7y, average : $9.6{\pm}3.9y$) and 51(4-11y, average : $9.0{\pm}2.4$) ADHD patients, and normal girls are 4(6-12y, average : $9{\pm}2.4y$) and 13(2-13y, average $10{\pm}3.5y$) ADHD patiens. Blood flow tracer $^{99m}Tc-ethylcysteinate$ dimer(ECD) injected as rCBF agent and take blood flow images after 30 min. during sleeping by SPECT camera. The anatomical region of hyperperfusion of rCBF in boys ADHD group is posterior cingulate gyrus and hyperperfusion rate is 15.39-15.77% according to p-value. And girls ADHD group appears at posterior cerebellum, Lt. cerbral limbic lobe and Lt. Rt. cerebral temporal lobe. These areas hyperperfusion rate are 24.68-31.25%. Hypoperfusion areas in boys ADHD,s brain are Lt. cerebral insular gyrus, Lt. Rt. frontal lobe and mid-prefrontal lobe, these areas decresed blood flow as 15.21-15.64%. Girls ADHD decreased blood flow regions are Lt. cerebral insular gyrus, Lt. cerebral frontal and temporal lobe, Lt. Rt. lentiform nucleus and Lt. parietal lobe. And hypoperfusion rate is 30.57-30.85% in girls ADHD. The girls ADHD group's perfusion rate is more variable than boys. The studies about rCBF in ADHD, should be separate with boys and girls.

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Superiority of Modifiled University of Wiscinsin Solution in the Prolonged Preservation of Isolated Rat Heart (적출 쥐 심장의 장시간 보존에 있어서 University of Wisconsin 수정 용액의 우수성)

  • Lee, Jae-Seong;Kim, Song-Myeong;Kim, Gyu-Tae
    • Journal of Chest Surgery
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    • v.26 no.6
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    • pp.427-440
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    • 1993
  • The paucity of donor hearts for transplantation can be remedied by distant heart procurement. Prolonging donor heart preservation is essential for successful clinical cardiac transplantation. Thirty-two isolated rat hearts were perfused with Krebs-Henseleit buffer solution for 15 minutes, arrested and preserved at 4 oC for 4 hours, and then reperfused for 25 minutes. The following three groups were prepared and hemodynamic changes, creatine kinase-MB isoenzyme levels and ultrastructural changes of the myocardium were analysed before and after cardiac arrest. ; Group I : the heart was arrested with the cardioplegic solution [Plegisol, potassium : 16 mM, sodium : 120 mM] and then stored in a solution with ionic compositions of the extracellular fluid [Hartman, potassium : 4 mM, sodium : 130 mM] ; Group II : the heart was arrested with the cardioplegic solution and stored in a solution with ionic compositions of the intracellular fluid [Modified Euro-Collins, potassium : 108 mM, sodium : 10 mM] ; Group III : the heart was arrested with the cardioplegic solution containing adenosine 20 uM, and then stored in a solution with ionic compositions of the intracellular fluid [Modified University of Wisconsin solution, potassium : 119 mM, sodium: 23 mM]. Left ventricular developed pressure at 20 minutes of the reperfusion was significantly higher in group III [64.3 $\pm$ 3.12 mmHg, p<0.01] and group II [58.3 $\pm$ 1.55 mmHg, p<0.05] as compared with group I [51.4$\pm$ 2.78 mmHg]. The time to induce cardiac arrest after infusion of cardioplegic solution with adenosine 20 uM [5.3 $\pm$ 0.30 second, p<0.005] was significantly shorter than without adenosine [10.6$\pm$ 0.55 second]. Coronary flow at 20 minutes of the reperfusion was augmented significantly in group III [9.6$\pm$ 0.50 ml/min, p<0.05, p<0.05] as compared with group I [8.0 $\pm$ 0.41 ml/min] and group II [8.1$\pm$ 0.51 ml/min]. Percentage recovery of left ventricular developed pressure at 20 minutes of the reperfusion was significantly higher in group III [94.6$\pm$ 2.51 %, p<0.005] as compared with group II and in group II [83.1 $\pm$ 1.22 %, p<0.005] as compared with group I [69.9 $\pm$ 1.73 %], and also percentage recovery of coronary flow at 20 minutes of the reperfusion was significantly higher in group III [82.3 $\pm$ 3.86 %, p<0.05] as compared with group II [71.4 $\pm$ 3.46 %] but there was no significant difference between group I and group II. Measured level of creatine kinase-MB isoenzyme at 15 minutes of the reperfusion was significantly lower in group III [1.23 $\pm$ 0.16 ng/ml, p<0.025] and group II [1.42$\pm$ 0.10 ng/ml, p<0.05] as compared with group I [1.79 0.14 ng/ml]. In the semiquantitative evaluation of the ultrastructural changes of the myocardium, mitochondrial score was lower in group III [0.7 $\pm$ 0.21] than in group I [3.1$\pm$ 0.28] and group II [1.7 $\pm$ 0.19], and also the other structural score was lower in group III [2.7$\pm$ 0.99] than in group I [7.9 $\pm$ 0.89] and group II [5.0 $\pm$ 1.22]. In conclusion, the solution with ionic compositions of the intracellular fluid is appropriate for prolonged cardiac preservation, and it appears to be better preserving method for distant procurement when the donor heart is rapidly arrested with cardioplegic solution containing adenosine 20 uM, and then stored with Modified University of Wisconsin solution.

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ROC Analysis of Visual Assessments Made in Gated Blood Pool Scans of Patients with Coronary Artery Disease (관상동맥질환에서 심장풀 스캔의 육안적 평가에 대한 ROC 분석)

  • Lee, Kyun-Han;Choi, Yoon-Ho;Lee, Bum-Woo;Moon, Dae-Hyuk;Koong, Sung-Soo;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.23 no.2
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    • pp.175-181
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    • 1989
  • Visual assessment of regional wall motion abnormality (RWMA) by gated blood pol scan (GBPS) serves as an useful parameter in the diagnosis, functional evaluation, and follow up in various clinical settings, but are still subject to some inherent limitations. On important problem may be the interobserver as well as intraobsever variation that may well be present due to the subjective nature of the interpretations. This study was carried out to determine the reliability and reproducibility of visual assessments made in GBPSs, and to observe the degree to which the results would be influenced by observer variation. Fifty two patients with coronary heart disease had resting GBPS and contrast ventriculography within 4 days appall. Contrast ventriculography-showed normal wall motion in 6 patients and the remaining 46 had RWMA in one or more segments. The anterior and left anterolateral views of all 52 GBPSs were analyzed by three independent observers, who selected from 5 scales, their level of confidence that there was RWMA in that segment. Reciever operating characteristic (ROC) curves for each analysis was plotted and the area under the curve $(\theta)$ was used as a parameter representing each observer's performance in his interpretations. The findings of contrast ventriculographies were used as the standard for RWMA. The apical and inferoapical segments showed the best correlation with contrast ventriculography ($\theta=0.90-0.94$, 0.81-0.94, respectively), and the inferior wall showed the poorest correlation $(\theta=0.70-0.74)$. The interpretations of the inferior, septal, apical, and posteroinferior, segments showed no difference between the observers, but there was significantly better performance in assessment by observer A compared to that by B or C for the anterolateral segments ($\theta=0.87$, 0.78, 0.76, respectively. p<0.01 for A vs B, p<0.05 for A vs C), as well as when all segments were considered altogether ($\theta=0.88$, 0.83, 0.82, respectively. both p<0.05). This was also true for the infero-apical segment between A and C ($\theta=0.09$, 0.81, p<0.05). The intraobserver variation, however, did not appear significant, with only the inferior segment for observer B showing any significant difference when observer A and B repeated the analysis 10 days latter. There was no difference in assessing dyskinesia, with all observers showing a high performance ($\theta=0.98$, 0.87, 0.97, respectively). The visual assessment of left ventricular ejection fraction by all three observers correlated well with the calculated value from a semiautomated method (Spearman's r = 0.91, 0.83, 0.83. p<0.01, p<0.05, p < 0.05). The assessment of LV and RV size also correlated well between the three observers (Kendall's w = 0.80, 0.51, p<0.01 for both left and right ventricles). The above findings suggest that RWMA visually assessed by GBPS correlates well with that done by contrast ventriculography. And although the observer's experience or skill may influence the results in certain segments, visual analysis of GBPS may serve as a reliable and reproducible means for evaluating ventricular function.

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