• 한국의학물리학회지:의학물리
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• 제27권4호
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• pp.196-202
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• 2016

We aim to develop the breast bolus by using a 3D printer to minimize the air-gap, and compare it to commercial bolus used for patients undergoing reconstruction in breast cancer. The bolus-shaped region of interests (ROIs) were contoured at the surface of the intensity-modulated radiation therapy (IMRT) thorax phantom with 5 mm thickness, after which the digital imaging and communications in mdicine (DICOM)-RT structure file was acquired. The intensity-modulated radiation therapy (Tomo-IMRT) and direct mode (Tomo-Direct) using the Tomotherapy were established. The 13 point doses were measured by optically stimulated luminescence (OSLD) dosimetry. The measurement data was analyzed to quantitatively evaluate the applicability of 3D bolus. The percentage change of mean measured dose between the commercial bolus and 3D-bolus was 2.3% and 0.7% for the Tomo-direct and Tomo-IMRT, respectively. For air-gap, range of the commercial bolus was from 0.8 cm to 1.5 cm at the periphery of the right breast. In contrast, the 3D-bolus have occurred the air-gap (i.e., 0 cm). The 3D-bolus for radiation therapy reduces the air-gap on irregular body surface that believed to help in accurate and precise radiation therapy due to better property of adhesion.

• 대한방사선치료학회지
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• 제32권
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• pp.41-52
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• 2020

목 적: Hypopharynx Cancer의 VMAT 치료 시 Neck 부분에 Commercial Bolus(이하 CB)와 3D Printing 기술로 제작한 3D Bolus를 각각 적용한 두 치료 계획을 비교함으로써 3D Bolus 적용의 선량학적 유용성, setup 재현성 및 효율성을 알아보고 임상적 적용 가능성을 평가하고자 한다. 대상 및 방법: CB를 적용한 RANDO phantom의 CT image를 바탕으로 3D Bolus를 동일한 형태로 제작하였다. 3D Bolus는 OMG SLA 660 Printer, MaterialiseMagics software를 이용하여 SLA기법을 통해 밀도 1.2 g/㎤의 폴리우레탄 아크릴레이트 수지로 출력하였다. CB와 3D Bolus를 적용한 두 CT image를 바탕으로 Hypopharynx Cancer의 VMAT 치료를 가정하여 치료 계획을 수립하였다. 수립한 두 치료 계획을 각각 18회에 걸쳐 CBCT image를 획득하였고, 매 회 setup time을 측정하여 치료 효율성을 평가하였다. 획득한 CBCT image를 바탕으로 전산화 치료계획 시스템 Pinnacle을 통해 Adaptive Plan을 진행함으로써 Target, 정상 장기 선량 평가와 Bolus Volume의 변화를 평가하였다. 결 과: 각 치료 계획에 대한 setup time은 CB 적용 치료 계획에 비해 3D Bolus 적용 치료 계획에서 평균 28 sec 감소하였다. 치료 전 기간 내 Bolus Volume 변화는 CB Initial Plan 83.9㎤에서 86.1±2.70㎤, 3D Bolus Initial Plan 92.2㎤에서 99.8±0.46㎤로 나타났다. CTV Min Value의 변화는 CB Initial Plan 191.6cGy에서 167.4±19.38cGy, 3D Bolus Initial Plan 167.3cGy에서 149.5±18.27cGy로 나타났다. CTV Mean Value의 변화는 CB Initial Plan 227.1cGy에서 228.3±0.38cGy, 3D Bolus Initial Plan 225.9cGy에서 227.7±0.30cGy로 나타났다. PTV Min Value의 변화는 CB Initial Plan 128.5cGy에서 74.9±19.47cGy, 3D Bolus Initial Plan 139.9cGy에서 83.2±12.92cGy로 나타났다. PTV Mean Value의 변화는 CB Initial Plan 225.4cGy에서 226.2±0.83cGy, 3D Bolus Initial Plan 224.1cGy에서 225.8±0.33cGy로 나타났다. 정상 장기 Spinal Cord에 대한 Max Value는 매 회 평균 135.6cGy로 동일하게 나타났다. 결 론: 본 논문의 실험 결과를 통해 불균등한 체표면에 대한 3D Bolus의 적용이 Commercial Bolus 적용에 비해 선량학적으로 유용하고 setup 재현성 및 효율성 또한 우수함을 알 수 있었다. 추후 3D Printing 재료의 다양성에 대한 연구와 함께 추가적인 사례 연구가 진행된다면 방사선 치료 분야에서 3D Bolus의 적용이 더욱 활발하게 진행될 것으로 사료된다.

• 한국의학물리학회지:의학물리
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• 제35권1호
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• pp.10-15
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• 2024

Purpose: This study aimed to comprehensively investigate the diverse characteristics of a novel commercial bolus, CLEANBOLUS-WHITE (CBW), to ascertain its suitability for clinical application. Methods: The evaluation of CBW encompassed both physical and biological assessments. Physical parameters such as mass density and shore hardness were measured alongside analyses of element composition. Biological evaluations included assessments for skin irritation and cytotoxicity. Dosimetric properties were examined by calculating surface dose and beam quality using a treatment planning system (TPS). Additionally, doses were measured at maximum and reference depths, and the results were compared with those obtained using a solid water phantom. The effect of air gap on dose measurement was also investigated by comparing measured doses on the RANDO phantom, under the bolus, with doses calculated from the TPS. Results: Biological evaluation confirmed that CBW is non-cytotoxic, nonirritant, and non-sensitizing. The bolus exhibited a mass density of 1.02 g/cm³ and 14 shore 00. Dosimetric evaluations revealed that using the 0.5 cm CBW resulted in less than a 1% difference compared to using the solid water phantom. Furthermore, beam quality calculations in the TPS indicated increased surface dose with the bolus. The air gap effect on dose measurement was deemed negligible, with a difference of approximately 1% between calculated and measured doses, aligning with measurement uncertainty. Conclusions: CBW demonstrates outstanding properties for clinical utilization. The dosimetric evaluation underscores a strong agreement between calculated and measured doses, validating its reliability in both planning and clinical settings.

• 한국의학물리학회지:의학물리
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• 제32권4호
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• pp.159-164
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• 2021

Purpose: We investigated the properties of CLEANBOLUS based on silicone with suitable characteristics for clinical use. Methods: We evaluated the characteristics of CLEANBOLUS and compared the results with the commercial product (Super-Flex bolus). Also, we conducted physical evaluations, including shore hardness, element composition, and elongation break. Transparency was investigated through the measured absorbance within the visible region (400-700 nm). Also, dosimetric characteristics were investigated with surface dose and beam quality. Finally, the volume of unwanted air gap was investigated based on computed tomography images for breast, chin, and nose using Super-Flex bolus and CELANBOLUS. Results: CLEANBOLUS showed excellent physical properties for a low shore hardness (000-35) and elongation break (>1,000%). Additionally, it was shown that CLEANBOLUS is more transparent than Super-Flex bolus. Dosimetric results obtained through measurement and calculation have an electron density similar to water in CLEANBOLUS. Finally, CLEANBOLUS showed that the volume of unwanted air gap between the phantom and each bolus is smaller than Super-Flex bolus for breast, chin, and nose. Conclusions: The physical properties of CLEANBOLUS, including excellent adhesive strength and lower shore hardness, reduce unwanted air gaps and ensure accurate dose distribution. Therefore, it would be an alternative to other boluses, thus improving clinical use efficiency.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.697-698
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• 2002

The dispersion of an aerosol bolus in acinus is analyzed numerically. Model geometry is a straight duct surrounded by an axisymmetric semicircular annulus which is expanding or contracting with breathing. Unsteady Wavier-Stokes equation is solved by CFX-F3D, an FVM commercial code and the trajectory of massless particle Is computed by Lagrangian method. For steady flow with no wall motion, mean velocity of aerosol bolus in alveolated duct is a little smaller than that in straight duct and dispersion in alveolated duct is comparable with the dispersion in straight tube. For expanding duct mean velocity of aerosol bolus approaches half of that in straight tube and effective diffusivity is smaller than that of straight tube. For contracting duct mean velocity of aerosol bolus becomes slightly larger than that in straight tube and effective diffusivity is comparable with the case of straight tube.

• 대한방사선기술학회지:방사선기술과학
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• 제43권1호
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• pp.9-14
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• 2020

Commercial plate bolus is generally used for treatment of surface tumor and required surface dose. We fabricated 3D-printed bolus by using 3D printing technology and usability of 3D-printed bolus was evaluated. RT-structure of contoured plate bolus in the TPS was exported to DICOM files and converted to STL file by using converting program. The 3D-printed bolus was manufactured with rubber-like translucent materials using a 3D printer. The dose distribution calculated in the TPS and compared the characteristics of the plate bolus and the 3D printed bolus. The absolute dose was measured inserting an ion chamber to the depth of 5 cm and 10 cm from the surface of the blue water phantom. HU and ED were measured to compare the material characteristics. 100% dose was distributed at Dmax of 1.5 cm below the surface when was applied without bolus. When the plate bolus and 3D-plate bolus were applied, dose distributed at 0.9 cm and 0.8 cm below the surface of the bolus. After the comparative analysis of the radiation dose at the reference depth, differences in radiation dose of 0.1 ~ 0.3% were found, but there was no difference dose. The usability of the 3D-printed bolus was thus confirmed and it is considered that the 3D-printed bolus can be applied in radiation therapy.

• Asian-Australasian Journal of Animal Sciences
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• 제20권9호
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• pp.1433-1437
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• 2007

Two field trials were carried out to evaluate the performance of a soluble glass copper, cobalt and selenium bolus for maintaining adequate levels of the three trace elements in yaks. Forty yaks were used in trial 1 and 60 yaks were used in trial 2. In each trial two commercial soluble glass boluses were administered to half of the yaks. Blood samples were taken from the jugular vein at day 0, 30, 60, 90 in trial 1 and at day 0, 45, 75 and 105 in trial 2. The samples were analysed for copper status (serum caeruloplasmin activity and copper concentration), cobalt status (serum vitamin $B_{12}$ concentration and cobalt concentration), selenium status (erythrocyte glutathione peroxidase activity and selenium concentration) and serum zinc concentration. The erythrocyte glutathione peroxidase activities, serum caeruloplasmin activities and serum vitamin $B_{12}$ concentrations for trial 1 and 2 were all significantly increased for the bolused yaks (p<0.001 or p<0.01) on all sampling days. The bolused yaks had a significantly higher selenium and copper status in serum than the control yaks on all sampling days in trial 1 and 2 (p<0.05 or p<0.01). There were no significant differences in zinc and cobalt concentrations between the bolused yaks and the controls.

• Journal of Nutrition and Health
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• 제28권4호
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• pp.345-354
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• 1995

Blenderized diets are not recommended because of difficulties in providing a constant content of nutrients, phoblems with viscosity and osmolarity, time needed for preparation, and increased risk of contamination. To determine the possibility of substituting commercial formulas for blenderized diets, 27 unconscious patients were randomized into two different groups : blenderized diet group(n=11) and commercial formula group(n=16). Blenderized diets were composed of food sources such as rice, milk, egg, juices and others, and its energy percentage of protein, fat, and carbohydrate was 15%, 30%, and 55%, respetively. Commercial enteral formulas provided 1 kcal/ml and the energy percentage of protein, fat and carbohydrate was 25%, 20% and 55% in greenbia(G) and 20%, 20%, and 60% in Greenbia-DM(GD), repectively. In commercial formula group, five patients with diarrhea, constipation, and high blood glucose level received GD, and the other eleven patients received G. All patients received their lipuid diet for 4 weeks through 16 French rubber nasogastric tube by bolus feeding 6 times daily. The patients in commercial formula group had a similar mean daily calorie intake to the patient in blenderized diet group, 32-34kcal/kg/d and 30-35kcal/kg/d, respectively. Patients given commercial formula gained an averge of 1.7kg in weight but those given blenderized diet lost an average of 2.6kg. There was a trend toward an increase in percent ideal body weight in commercial formula group(94$\pm$5 vs 99$\pm$6%). However, blenderized diet group showed a trend toward a decrease in percent ideal body weight(106$\pm$5 vs $101\pm$6%). The initial levels of total lymphocyte counts, serum albumin and tranferrin were below the normal rante, The mean daily protein intake was significanlty higher for commercial formula group(2.0-2.1g/kg/d) than for blenderized diet group(1.1-1.3g/kg/d). Patient fed cormmercial formula for 4 weeks showed a trend toward an increase in serum albumin(8.1%) and a significant increase in serum transferrin(32.1%) without increasing the levels of blood glucose. GOT, GPT, blood urea nitrogen and serum creatinine. In the blenderized diet group, however, no significant improvement were obseved in the concentration of serum albumin and transferin, compared to initial value. There was a trend toward a decrese in the level of hemoglobin and hematocrit in blenderized deit group but no significnat change in commercial formulas goups. All patients tolerated both diets well and no significant complications were encountered. The results indicate that the commercial enteral formulas tested in this study can be an effective substitution for blenderized diet in unconscious tube-fed patients.

• Journal of Nutrition and Health
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• 제25권7호
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• pp.668-683
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• 1992

To evaluate the current practices of the tube feeding and the status of tube feeding patient 76 adult in-patients at 6 hospitals located in Seoul and Chung-buk province were examined through reviewing patient charts observing patients and interviewing patients nurses dietitians patients' family or care-givers. The results were as follows : 1) An average age of the patients was 54.5 years with 41% over 60 years old. Patients with decreased mental status dysphagia esophageal obstruction and respiratory problem were fed by tubes. 2) The range of duration of tube feeding is between 4 days and 6 years. Most patients were received formula through nasogastric tube(89.5%) while 7.9% of gastrostomy and 2.6% of jejunostomy. Administration method for formula were bolus feeding regardless of the route of formula delivery. 3) Mean total calories received for men were 1590 kcal and 1450 kcal for female. Mean volume per meal was 282m, l and mean frequency of feeding was 5.68 while mean feeding interval 3$\frac{1}{4}$ hours and mean rate of infusion 68.4ml/min. All patients received hospital-blenderi-zed formula as the major source of nutrition. Home-blenderized formula and commercial formula as a supplement were used 35%, 13.2% respectively. 4) Thirty-eight percent of patients was hypoalbuminemia and 61% was at the moderate level of deficiency in hemoglobin. 5) Complications associated with tube feeding were diarrhea (22.4%) constipation(21.1%) vomiting(11.8%) and so on. 6) Serum albumin levels of patients who have complications associated with tube feeding were significantly lower than those of patients without complications In planning a tube feeding regimen the type of a formula must be integrated with both a delivery system and a protocol for administering the tube feeding. the multidisciplinary effort required to deliver enteral therapy is essential to improve current practices used at hospitals.