• Journal of Magnetics
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• 제19권3호
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• pp.248-254
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• 2014

The purpose of this study is to figure out how uptake counts of technetium ($^{99m}Tc$) among radioisotopes in the human body are affected if computed tomography (CT), magnetic resonance imaging (MRI) and isotope examination are performed consecutively. $^{99m}Tc$ isotope material, iodinated contrast media for CT and paramagnetic contrast media for magnetic resonance (MR) were used as experimental materials. First, $^{99m}Tc$ was added to 4 cc normal saline in a test tube. Then, 2 cc of CT contrast media such as $Iopamidol^{(R)}$ and $Dotarem^{(R)}$ were diluted with 2 cc normal saline, and 2cc of MRI contrast media such as $Primovist^{(R)}$ and $Gadovist^{(R)}$ were diluted with 2 cc normal saline. Each distributed contrast media was a total of 4 cc and included 10m Ci of $^{99m}Tc$. A gamma camera, a LEHR (Low energy high resolution) collimator and a pin-hole collimator were used for image acquisition. Image acquisition was repeated a total of 6 times and 120 frames were obtained and uptake counts of $^{99m}Tc$ were measured (from this procedure). In this study, as a result of measuring the uptake counts of $^{99m}Tc$ using the LEHR collimator, the uptake counts were less measured in all contrast media than normal saline as a reference. In particular, the lowest uptake counts were measured when $Gadovist^{(R)}$, contrast media for MRI, was used. However, the result of measuring the uptake counts of $^{99m}Tc$ using the pin-hole collimator showed higher uptake counts in all contrast media, except for $Iopamidol^{(R)}$, than normal saline as a reference. The highest uptake counts were measured particularly when $Primovist^{(R)}$, contrast media for MRI, was used. In performing the gamma camera examination using contrast media and $^{99m}Tc$, it is considered significant to check the changes in the uptake counts to improve various diagnosis values.

• Journal of Magnetics
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• 제19권4호
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• pp.372-377
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• 2014

The purpose of the study is to investigate how uptake counts of $^{201}Tl$ of radioisotopes in the human body could change, when taking computed tomography and magnetic resonance imaging right after injecting contrast media. $^{201}Tl$ radioisotope substances of iodine contrast medium, which is a computed tomography contrast medium, and paramagnetic contrast medium, which is an magnetic resonance imaging contrast medium, were used as study materials. First, $^{201}Tl$ was put into 4 cc of normal saline in test tube, and then a computed tomography contrast medium of Iopamidol$^{(R)}$ or Dotarem$^{(R)}$, was put into 2 cc of normal saline in test tube. An magnetic resonance imaging contrast medium of Primovist$^{(R)}$ or Gadovist$^{(R)}$ was also put into 2 cc of normal saline in test tube. Each contrast medium was distributed to make $^{201}Tl$ as 3 mCi, with a total of 4 cc. Gamma camera, low energy high resolution collimator, and pinhole collimator were used to obtain images. The uptake count of $^{201}Tl$ was measured with 1000 frames of images, and obtained after 10 times of repetition. This study revealed that the use of Gadovist$^{(R)}$, which is an magnetic resonance imaging contrast medium, showed the smallest number of uptake count, after measuring $^{201}Tl$ uptake count by low energy high resolution collimator. On the other hand, the use of Iopamidol$^{(R)}$, which is a computed tomography contrast medium, showed the biggest difference in uptake count, when measuring $^{99m}Tc$ uptake count by Pinhole collimator. When examining with gamma camera, using contrast medium and $^{201}Tl$, identifying the changes of uptake count is very important for improving the value of diagnosis.

• 대한핵의학회지
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• 제21권1호
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• pp.9-16
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• 1987

It is well-known that hepatic scintigraphv have been found to be less sensitive and specific in the detection of the diffuse hepatocellular diseases than that of the space-occupying lesions. To obtain the higher diagnostic specificity and sensitivity, we, using the computer quantitation, have attempted to analyze hepatic and extrahepatic $^{99m}Tc-tin$ colloid uptake patterns in various diffuse hepatocellular diseases retrospectively. The studied groups consisted of 116 cases of normal, 67 cases of acute hepatitis, 112 cases of chronic hepatitis, 61 cases of liver cirrhosis, 47 cases of fatty liver, 12 cases of hepatoma and 9 cases of metastasis, making total 424 cases. Scintigraphic imagings were obtained in the anterior, right lateral and posterior projections using high-resolution collimation, and simultaneously these gamma data were acquisited into the computer system. Both large region of interest (ROI) using light pen and ROI computer program were placed over right lobe, left lobe of liver, spleen and cardiac blood pool. Total counts in ROI were divided by the number of pixels in the ROI, and mean count rate per pixels calculated. Mean right-lobe counts were divded by mean-left lobe counts to determine right-to-left hepatic lobe ratio and mean spleen counts were divided by mean liver counts to determine spleen to liver ratio. The results were as follows. 1) Of 424 cases, 292 were male and 132 were female. The majority of age distribution was in $30\sim49$ (54.5%). 2) Inter-observer between two independant operators and inter-method between drawing by light-pen and ROI computer program variations were not significant. 3) The uptake count values (per pixel) determined at each area in normal group were $106.53{\pm}18.35$ in right lobe, $79.00{\pm}13.82$ in left lobe, $17.52{\pm}8.31$ in spleen and $8.09{\pm}3.43$ in cardiac blood pool. 4) In liver cirrhosis, right lobe uptake was decreased but spleen and cardiac blood pool uptakes were increased (p<0.01). 5) Right-to-left hepatic lobe uptake ratio was $1.37{\pm}0.24$ in normal group and significantly low in chronic hepatitis, liver cirrhosis and fatty liver, and more or less low in acute hepatitis. 6) Spleen-to-right hepatic lobe uptake ratio was $0.17{\pm}0.09$ in normal group and high in chronic hepatitis and liver cirrhosis. 7) The computer-quantitation of hepatic and extrahepatic uptake patterns thought to be sensitive and useful method in the interpretation of liver scintigram.

• 대한방사선기술학회지:방사선기술과학
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• 제46권5호
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• pp.401-408
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• 2023

Thyroid uptake measurements can be subject to measurement errors due to the scoping and positioning of the thyroid gland. To compensate for these limitations, the clinical utility of the thyroid simultaneous counting method as an alternative to thyroid uptake measurement was analyzed and evaluated experimentally through quantitative analysis of images acquired after thyroid scanning. Experimental data were obtained using a Gamma camera (GE infinia), a thyroid uptake system (KOROID 1), and a thyroid neck phantom. Based on the thyroid uptake rate of 1-5% according to the protocol of thyroid scan test (^99mTcO₄ - , 370 MBq) in normal results, ^99mTcO₄ - was set in the range of 3.7-18.5 MBq (Matrix: 256×256, Scan time: 1 min, collimator: pin hole, phantom-collimator distances: 7 cm). The acquired images were corrected for the attenuation of isotopes due to the set-up time and half-life by applying the Auto Region of interest (ROI) drawing system, and the significance of the experimental results was evaluated by Multiple linear regression analysis (SPSS, ver. 22, IBM). The thyroid uptake rate showed a significant correlation between the dose and the measured counts when using the thyroid uptake system equipment. Meanwhile, the quantitative analysis counts of phantom images using Gamma camera also showed a significant correlation. Thus confirmed that the correlation between these two experiments was statistically significant (P<0.05). The simultaneous counting protocol, which indirectly measures thyroid uptake from thyroid scans, is likely to be clinically relevant if complemented by additional studies with different variables in patients with thyroid disease.

• 한국방사선학회논문지
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• 제9권4호
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• pp.235-238
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• 2015

소아 $^{99m}Tc-DMSA$ 검사에서 방광의 포함 여부에 따른 신장 섭취율의 차이를 비교 하였다. 팬텀실험과 임상실험으로 진행되었으며 3개의 컵으로 좌, 우측신장 그리고 방광에 위치시키고 좌, 우측 신장의 방사능은 일정한 양( 1.0 )으로 고정하였고 방광에 해당되는 컵에는 0, 0.5, 1, 2배 방사능의 차이를 두어 영상을 획득하였다. 임상환자는 $^{99m}Tc-DMSA$ (300uCi, 11MBq)을 주사하여 2시간 뒤 동일하게 영상 획득하여 각각 정량 분석하였다. 통계분석은 SPSS(ver 22.0) 으로 대응표본 T검증(paired T-test)을 사용하여 분석하였고 p<0.05는 통계적으로 유의하다고 판단하였다. 방광의 방사능을 제외한 양측 신장 섭취율은 $29.83{\pm}8.8%$(좌측), $24.29{\pm}6.66%$(우측)이었고, 방광을 포함했을 때 신장 섭취율은 $26.65{\pm}8.03%$(좌측), $21.78{\pm}6.24%$(우측)이었다. 신장 섭취율은 방광의 소변(방사능)이 증가할수록 양측 신장의 섭취율은 감소하였다. 이는 $^{99m}Tc-DMSA$ 신장스캔 시 좌, 우측 신장에서 방사능을 계수할 때 방광의 소변에 포함된 방사능의 계수가 포함되어 신장 섭취율 공식에서 총 계수가 포함되므로 실제 양측 신장 섭취율의 값이 감소되었다.

• 한국의학물리학회지:의학물리
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• 제12권2호
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• pp.103-112
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• 2001

목적: 최근 국내의 핵의학 계측기기 및 감마카메라의 정도관리 수행현황을 파악하고, 핵의학 계측기기와 감마 카메라의 정도관리를 수행하고자 하였다. 방 법: 최근 국내의 핵의학 계측기기 및 감마 카메라의 정도관리 수행현황은 총 53개 병원을 대상으로 설문조사방법을 이용하여 수행하였다. 이들의 정도관리 연구는 Capintec의 CRC-15 기종의 dose calibrator와 Tc-99m 35.52 MBq을 사용하여 2분 간격으로 정밀도를 측정하였다. Nucleus사의 기종의 Thyroid Uptake system은 Tc-99m 5.14 MBq을 이용하여 1분 간격으로 10초동안 정밀도를 측정하였다. 지름이 15 cm이고 높이가 각각 12 cm, 30 cm인 원통형 팬텀과 TC-99m을 이용하여 저에너지 고해상도 조준기가 부착된 CeraSPECT$^{TM}$의 예민도를 측정하였다. CeraSPECT$^{TM}$와 일반 평면카메라와의 예민도에 대한 특성비교를 위하여 Varicam (Elscint Ltd, Israel) 감마 카메라로 영상을 얻었다. CeraSPECT$^{TM}$로 획득한 자료로 각 슬라이스에 대한 보정상수를 계산하였다. Elscint 사의 Varicam 감마 카메라의 정도관리를 위해 저에너지 고해상도 조준기를 부착하고 140 keV 중심20% 에너지창, 256$\times$256 또는 512$\times$512 메트릭스 크기를 이용하여 시스템의 평면 예민도, 균일도, 계수율 및 공기중과 산란매질에서의 공간 분해능을 측정하였다. 결 과: 핵의학 계측기기 및 감마 카메라의 정도관리 수행율은 dose calibrator와 well counter의 경우 매우 저조한 수행율을 나타내었으며 그 외 감마 카메라 등은 대체로 양호한 수행율을 나타내었다. dose calibrator의 정밀도 측정은 $\pm$1.4%(<$\pm$5%)의 결과를 얻었고, thyroid uptake system의 정밀도 측정은 chi^2=29.7(>16.92)의 결과를 얻었다. Varicam 감마 카메라의 경우 슬라이스들간에 전반적으로 균일한 민감도를 보여주었으나 CeraSPECT$^{TM}$ 의 경우는 위쪽과 아래쪽 부분의 슬라이스들은 민감도가 두드러지게 떨어져 있었고 팬텀의 중심부분 슬라이스들은 민감도가 매우 높은 것으로 나타났다. 계산한 보정 상수를 이용하여 CeraSPECT$^{TM}$로 얻은 환자 자료를 보정하였을 때 보정전에 비하여 전반적으로 균일한 영상을 얻을 수 있었다. 감마 카메라의 시스템 평면 예민도 측정 결과는 4.39 CPM/MBq 이었으며, 시스템 균일도는 첫 번째 검출기와 두번째 검출기가 각각 2.14%, 3.79%로 나타났다. 시스템 계수율 측정의 경우 입력 계수율 R_20%가 각각 102,407 counts/sec (head 1), 113,427 counts/sec (head 2)일 때 20% 계수율 손실이 발생했을 때의 측정된 계수율 C_20%는 각각 81,926 counts/sec (head 1), 90,741 counts/sec (head 2) 이었다. 공기 중에서의 시스템의 공간 분해능은 FWHM이 8.16 m, FWTM이 14.85 mm이었고, 산란매질에서는 시스템의 공간 분해능은 FWHM이 8.87 mm, FWTM이 18.87 mm이었다. 결 론: 정확하고 신뢰도 높은 검사를 위해 정도관리는 필수이며, 이에 대한 명확한 인식과 실질적인 수행이 반드시 뒤따라야 할 것으로 사료되었다

• 대한방사선협회지
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• 제29권1호
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• pp.44-49
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• 2003

감마카메라를 이용하여 영상화할 수 있는 $^{99m}Tc-DMSA$ 신장 검사는 비침습적으로 신장의 기능과 형태를 동시에 평가할 수 있고, 신장 기능의 이상은 형태학적인 변화 보다 먼저 나타나기 때문에 다른 검사보다 $^{99m}Tc-DMSA$ 신장 검사를 이용하면 병변을 조기에 진단할 수 있는 장점이 있다. 신장의 상대적 기능 평가시에 깊이 보정, 총 계수 또는 평균 계수의 사용, BKG 보정, SPECT 검사의

• 대한수의학회지
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• 제6권1호
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• pp.24-30
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• 1966

In order to observe the effect of the injected radioactive iodine-$I^{131}$ on the uptake in thyroid of normal male guinea pigs and P.B.$I^{131}$ conversion ratio of $I^{131}$ in serum, 24 matured male guinea pigs were divided in 4 groups and $35{\mu}c$, $70{\mu}c$, $140{\mu}c$ and $280{\mu}c$ per kg of body weight respectively were injected subcutaneously. 1. The uptake rates of radioactveiodine-$I^{131}$ by external counts of thyroidal uptake reached the maximum level of uptake in 24 hours after injection. 2. As the injected amount increases, the uptake rates of maximum levels and release rate were increased. 3. Uptake rate in the removed thyroid have shown no statistical in the $35{\mu}c$ and $70{\mu}c$ groups of injected guinea pigs. 4. There was no statistical significance in $140{\mu}c$ and $280{\mu}c$ groups of injected guinea pigs. 5. P.B.$I^{131}$ conversion ratio of $I^{131}$ in serum was not in proportion to injected amounts: 61.0%(35), 70.2%(70), 75.3%(140) and 64.8%(280).

• Journal of Gastric Cancer
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• 제17권4호
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• pp.384-393
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• 2017

Purpose: The tumor microenvironment is known to be associated with the metabolic activity of cancer cells and local immune reactions. We hypothesized that glucose metabolism measured by 2-deoxy-2-($^{18}F$)fluoro-D-glucose ($^{18}F-FDG$) positron emission tomography (PET)-computed tomography (CT) ($^{18}F-FDG$ PET-CT) would be associated with local immune responses evaluated according to the presence of tumor infiltrating lymphocytes (TILs). Materials and Methods: We retrospectively reviewed 56 patients who underwent $^{18}F-FDG$ PET-CT prior to gastrectomy. In resected tumor specimens, TIL subsets, including cluster of differentiation (CD) 3, CD4, CD8, Forkhead box P3 (Foxp3), and granzyme B, were subjected to immunohistochemical analysis. The prognostic nutritional index (PNI) was calculated as: ($10{\times}serum$ albumin value)+($0.005{\times}peripheral$ lymphocyte counts). Additionally, the maximum standard uptake value ($SUV_{max}$) was calculated to evaluate the metabolic activity of cancer cells. Results: The $SUV_{max}$ was positively correlated with larger tumor size (R=0.293; P=0.029) and negatively correlated with PNI (R=-0.407; P=0.002). A higher $SUV_{max}$ showed a marginal association with higher CD3 (+) T lymphocyte counts (R=0.227; P=0.092) and a significant association with higher Foxp3 (+) T lymphocyte counts (R=0.431; P=0.009). No other clinicopathological characteristics were associated with $SUV_{max}$ or TILs. Survival analysis, however, indicated that neither $SUV_{max}$ nor Foxp3 held prognostic significance. Conclusions: FDG uptake on PET-CT could be associated with TILs, especially regulatory T cells, in gastric cancer. This finding may suggest that PET-CT could be of use as a non-invasive tool for monitoring the tumor microenvironment in patients with gastric cancer.

• 대한핵의학회지
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• 제21권2호
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• pp.151-154
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• 1987

Total 114 patients were studied prospectively with radioiodine uptake (RAIU) and $^{99m}TcO_4^-$ thyroid scan to design a very simple, rapid and inexpensive method measuring the thyroid uptake on thyroid scan. After the RAIU was obtained at 24 hours after P.O. of $^{131}I$, Thyroid scan was performed at 20 minutes after LV. of $^{99m}TcO_4^-$ and the bilateral salivary glands were included in the scan field. Pinhole collimated and computer assisted gamma camera was used. Three regions of interest were set on each salivary gland and on the thyroid by automatic edge detection method. Mean counts per pixel were calculated for each ROI and the salivary-thyroid ratio (STR) was defined as; $$STR(%)=\frac{Mean\;counts\;per\;pixel\;of\;salivary\;glands\;(KC)}{Mean\;counts\;per\;pixel\;of\;thyroid\;gland\;(KC)}\times100$$ 114 cases consisted of 41 normal, 55 hyperthyroid and 18 hypothyroid patients and correlation between the STR and the RAID were evaluated in total and each group. The STR and the RAID showed reverse linear regression in 114 cases (r= -0.8, P=0) and closer correlation was shown in hyperthyroid group (r= -0_9, p=0). Mean STR in normal group was 47.6%. In predicting the RAID by STR, sensitivity and specificity were 88.3% and 64.9% in 114 cases and 95.3% and 83.3% in hyperthyroid group. It is recommended that the STR be used in place of the RAID giving same information at saving time, money and radiation exposure.