• 한국임상수의학회지
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• 제34권5호
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• pp.330-334
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• 2017

The aim of this study was to establish an injection protocol of a test bolus and a main bolus of contrast material for computed tomographic pulmonary angiography (CTPA) for visualizing optimal pulmonary arteries in normal beagle dogs. CTPA using a test bolus method from either protocol A or B were performed in each of four normal beagle dogs. In protocol A, CTPA was conducted with a scan duration for around 8 s, setting the contrast enhancement peak of the pulmonary trunk in the middle of the scan duration. The arrival time to the contrast enhancement peak was predicted from a previous dynamic scan using a test bolus (150 mg iodine/kg) injected with the same injection duration using for a main bolus (450 mg iodine/kg). In protocol B, CTPA was started at the predicted appearance time of contrast material in the pulmonary trunk based on a previous dynamic scan using a test bolus injected with the same injection rate as a main bolus. CTPA using protocol A showed the optimal opacification of the pulmonary artery with pulmonary venous contamination. Proper CTPA images in the absence of venous contamination were obtained in protocol B. CTPA with a scan duration for 8 s should be started at the appearance time of contrast enhancement in the pulmonary trunk, which can be identified exactly when a test bolus is injected at the same injection rate used for the main bolus.

• Journal of Magnetics
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• 제22권2호
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• pp.234-237
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• 2017

This study is aimed to optimize a location of region of interest (ROI) in test bolus carotid contrast enhanced magnetic resonance angiography (CE-MRA) at 3.0T. A total of consecutive 270 patients with no cardiovascular and vessel diseases were selected. Patients underwent elliptical centric 3D CE-MRA with the test bolus technique to identify the individual arterial arrival time. Quantitative measurements were performed by drawing ROIs of $25mm^2$ and signal intensities (SI) were measured in the center of common carotid artery (CCA), internal carotid artery (ICA) and aortic arch (AA). As a result, ROIs located within AA showed a significantly clarified arterial peak and over three times increased SI, while no significant arterial peak time differences were observed compared to ROIs located within CCA. In conclusion, it was demonstrated that the aortic arch is the optimal position to locate ROI in test bolus images of the carotid CE-MRA.

• Korean Journal of Radiology
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• 제1권2호
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• pp.91-97
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• 2000

Objective: To determine whether the time-intensity curves acquired by test and main dose contrast injections for MR angiography are similar. Materials and Methods: In 11 patients, repeated contrast-enhanced 2D-turbo-FLASH scans with 1-sec interval were obtained. Both test and main dose timeintensity curves were acquired from the abdominal aorta, and the parameters of time-intensity curves for the test and main boluses were compared. The parameters used were arterial and venous enhancement times, arterial peak enhancement time, arteriovenous circulation time, enhancement duration and enhancement expansion ratio. Results: Between the main and test boluses, arterial and venous enhancement times and arteriovenous circulation time showed statistically significant correlation (p < 0.01), with correlation coefficients of 0.95, 0.92 and 0.98 respectively. Although the enhancement duration was definitely greater than infusion time, reasonable measurement of the end enhancement point in the main bolus was impossible. Conclusion: Only arterial and venous enhancement times and arteriovenous circulation time of the main bolus could be predicted from the test-bolus results. The use of these reliable parameters would lead to improvements in the scan timing method for MR angiography.

• 한국방사선학회논문지
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• 제14권6호
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• pp.741-746
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• 2020

사지부위에 많이 발생하는 연부조직육종의 방사선치료에 사용하는 쌀을 이용한 볼루스의 적용에서 쌀의 품종에 따른 형태적 차이에 따라 달라지는 방사선량분포의 차이가 발생하는지를 알기 위하여 일반적인 국산 쌀과 낱알의 크기가 작은 태국산 쌀을 각각 적용한 쌀 볼루스의 선량분포 민감도를 비교하였다. 쌀 볼루스를 적용하지 않는 팬텀, 국산 쌀을 사용한 쌀 볼루스를 적용한 팬텀, 태국산 쌀을 사용한 쌀 볼루스를 적용한 팬텀에 동일한 방사선치료계획을 수립하고 동일한 지점 12곳에 대한 선량을 비교하였다. 등중심점에 대하여 100 cGy를 처방하였으며, 낱알의 크기가 작고 긴 태국산 쌀을 이용한 쌀볼루스에서 평균 103.57±1.98 cGy, 국산 쌀 볼루스에서 평균 104.27±2.12 cGy, 볼루스가 없는 팬텀에서 104.99±6.40 cGy의 선량분포를 보였다. Wilcoxon's Signed Rank test에서 태국산 쌀 볼루스와 국산 쌀 볼루스의 선량분포가 유의한 차이를 보였다(p=.011). 낱알의 크기가 작고 긴 태국산 쌀을 이용한 볼루스에서 더 균등한 선량분포를 보임을 확인하였으며 임상에서 이를 고려하면 더 양질의 의료서비스를 제공할 수 있을 것이다.

• 한국임상수의학회지
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• 제35권3호
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• pp.93-96
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• 2018

This study aimed to establish an injection protocol to determine the precise CT scan timing in canine abdominal multi-phase CT using the test bolus method. Three dynamic scans with different contrast injection parameters were performed using a crossover design in eight normal beagle dogs. A contrast material was administered at a fixed dose of 200 mg iodine/kg as a test bolus for dynamic scans 1 and 2, and 600 mg iodine/kg as a main bolus for dynamic scan 3. The contrast materials were administered with 1 ml/s in dynamic scan 1, and 3 ml/s in dynamic scan 2 and 3. The mean arrival time to the appearance of aortic enhancement in dynamic scan 3 was similar to that in dynamic scan 2, and different significantly to that in dynamic scan 1. The mean arrival time to the peak aortic and pancreatic parenchymal enhancement in dynamic scan 3 was similar to that in dynamic scan 1, and different significantly to that in dynamic scan 2. In multi-phase CT scan, a test bolus should be injected with the same injection duration of a main bolus, to obtain the precise arrival times to peak of arterial or pancreatic parenchymal enhancement.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 1999년도 제4차 추계학술대회 초록집
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• pp.44-44
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• 1999

• 대한디지털의료영상학회논문지
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• 제13권3호
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• pp.99-103
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• 2011

Radiation Therapy has been used in the treatment of breast cancer for over 80 years. Technically, it should include a part or all of such areas as chest wall or breast, axilla, internam mammary nodes and supraclavicular nodes. The purpose of this study is treated breast cancer patient to use 6 MV, 10 MV with bolus so that we observe changing of skin dose and evaluate those usefulness. Using woman's phantom, after CT simulate scanning, Through RTP system to make treatment plan, select three any place. And then, we measure that dose rate. After moving the phantom to linac, we put for TLD to three point same as RTP system which we put on the phantom. We exposed 6 MV, 10 MV with bolus and without so that it is measured dose by TLD device(4000 Harshaw). As a reult expose 6 MV,10 MV, it differences 10%, 15% according to bolus and withoout bolus where lateral point from RAO, LPO beam, other one is 20% where the furthest from both beams. To use bolus in the hospital is material to include closely part at skin among tissue of breast cancer. Acquired skin dose from RTP system is uncertainity. So it has to test another system likely TLD or other dosimetry system. Also exposed field of breast cancer is included inhomogeneity such as lung, bone and so on. Therefore it has to be accomplished a dose calculating of inhomogeneity part from treatment plan.

• 대한방사선치료학회지
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• 제18권2호
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• pp.105-112
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• 2006

목 적: 전자선 조사야 내에서 조직결손이 큰 경우 일어나는 선량의 불균일도를 물 볼루스를 사용하여 감소시키고자 하였으며 이 때 물을 쉽게 제어할 수 있는 방법을 강구하였다. 대상 및 방법: 조직결손이 심하여 일반적인 볼루스를 사용할 수 없는 환자에 대하여 치료계획 장치(Pinnacle, Philips, USA)의 결손조직 보상 기능을 사용하여 이를 보상하는 치료계획을 수립하였다. 결손 된 조직 부분에 해당하는 조직 보상체는 물을 사용하기로 하였고, Mev-green을 환자 몸 위에서 만들어 물을 보다 쉽게 제어할 수 있는 증기를 제작하였다. 제작된 장치는 환자 개개인의의 체표 모양에 맞게 제작하였다. 물을 채운 비닐을 Mev-green 안쪽에 넣어 물이 결손 된 조직을 보상해주는 역할을 하도록 하였다. 자체 제작한 물 볼루스의 효과를 평가하기 위해 CT스캔을 시행한 후 결손조직 보상 기능을 이용하여물 볼루스 사용전후의 치료계획을 수립하여 그 결과를 비교하였다. 결 과: 흉벽 조직결손으로 인해 생긴 선량의 불균일도는 자체 제작한 물 볼루스 사용 시 감소하였고, 또한 폐와 간의 정상조직의 선량 역시 감소하였다. 볼루스를 사용하지 않은 경우 최대 표적선량이 132%였으나 물 볼루스 사용 시는 최대 표적선량이 110.4%로 21.6%가 감소하였다. 그리고 우측 폐에 들어가는 선량이 볼루스를 사용하지 않은 경우 19.49%에서 물 볼루스를 사용한 경우 1.02%로 줄었고 간에서는 볼루스를 사용하지 않은 경우 17.1%에서 물 볼루스 사용으로 인해 6.8%로 감소하여 정상조직을 보호할 수 있었다. 결 론: 자체 제작한 물 볼루스 장치를 사용한 결과 PTV내에서 선량의 균일도가 향상됨을 확인할 수 있었고, 인접장기 선량의 현저한 감소로 정상조직을 더 많이 보호할 수 있었다. 이 방법은 불균등한 체표에서의 전자선 치료 시 발생할 수 있는 정상조직의 부작용을 줄일 수 있을 것으로 예상된다.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 1999년도 제4차 추계학술대회 초록집
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• pp.107-107
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• 1999

• Korean Journal of Radiology
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• 제19권6호
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• pp.1021-1030
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• 2018

Objective: We evaluated the effect of various patient characteristics and time-density curve (TDC)-factors on the test bolus-affected vessel enhancement on coronary computed tomography angiography (CCTA). We also assessed the value of generalized linear regression models (GLMs) for predicting enhancement on CCTA. Materials and Methods: We performed univariate and multivariate regression analysis to evaluate the effect of patient characteristics and to compare contrast enhancement per gram of iodine on test bolus (${\Delta}HUTEST$) and CCTA (${\Delta}HUCCTA$). We developed GLMs to predict ${\Delta}HUCCTA$. GLMs including independent variables were validated with 6-fold cross-validation using the correlation coefficient and Bland-Altman analysis. Results: In multivariate analysis, only total body weight (TBW) and ${\Delta}HUTEST$ maintained their independent predictive value (p < 0.001). In validation analysis, the highest correlation coefficient between ${\Delta}HUCCTA$ and the prediction values was seen in the GLM (r = 0.75), followed by TDC (r = 0.69) and TBW (r = 0.62). The lowest Bland-Altman limit of agreement was observed with GLM-3 (mean difference, $-0.0{\pm}5.1$ Hounsfield units/grams of iodine [HU/gI]; 95% confidence interval [CI], -10.1, 10.1), followed by ${\Delta}HUCCTA$ ($-0.0{\pm}5.9HU/gI$; 95% CI, -11.9, 11.9) and TBW ($1.1{\pm}6.2HU/gI$; 95% CI, -11.2, 13.4). Conclusion: We demonstrated that the patient's TBW and ${\Delta}HUTEST$ significantly affected contrast enhancement on CCTA images and that the combined use of clinical information and test bolus results is useful for predicting aortic enhancement.