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Tissue-mimicking material (TMM) is a fundamental element and important to replace actual tissue. One TMM application creates real mimicking models or phantoms to assess the performance of mammographic imaging modalities through quality assurance and control procedures. The TMM must have tissue equivalence properties to reflect the actual tissue. This tissue equivalence assessment depends on the attenuation value of the material. Therefore, this study aimed to evaluate the linear attenuation coefficient and image quality of 3D Printed materials using mammography computed radiography. This study used polyvinyl alcohol (PVA) filament with a percentage variation of 85-100% which was used to make breast phantoms with a 3D Printer. The phantom was box-shaped with an area of 10×10 cm² with a thickness of 1 cm and featured cylindrical, fiber, and speckled lesions. The phantom was exposed to an energy range of 23 – 35 kV, 40 mA, gantry angle of 0°, filter using Mo/Mo, and without compression. The results showed that the linear attenuation coefficient decreased with increasing energy with values of 3.232 – 0.586 cm−1 for 100% PVA, 0.986 – 0.024 cm−1 for 95% PVA, and 0.682 – 0.019 cm−1 for 85% PVA. Meanwhile, the results of image quality analysis from the signal difference-to-noise ratio parameters of cylindrical, fiber, and speckles lesions can be clearly distinguished from the background for all voltages, except on 23 kVp. In the end, 3D Printed PVA filament phantoms provide promising potential as mammographic phantoms from attenuation coefficient and image quality. [ABSTRACT FROM AUTHOR]

In the medical field, the ultrasound phantoms had been used to perform device performance testing, ultrasound-guided biopsy training, the development and validation of ultrasound imaging techniques. Polyvinyl alcohol (PVA) materials have been widely used for tissue equivalent phantom materials. However, the acoustic and mechanical properties have not been comprehensively investigated. Therefore, this study aims to measure and assess the acoustic and mechanical properties of PVA material with varying densities for the tissue-mimicking material of an ultrasound phantom. The research method started with making PVA samples with densities of 7, 10, and 15% of the total weight. Each variation of PVA density was dissolved in distilled water and stirred at 300 rpm, a temperature of 175°C. The solution was stirred until the PVA was completely dissolved in distilled water and the solution was poured into a polylactic acid mold with dimensions of 10 × 10 cm2, 1 cm thickness. PVA samples were subjected to one freeze-thaw cycle. The samples were tested for acoustic properties at frequency 1 – 5 MHz. Elasticity properties were tested using a dynamic mechanical analyzer, and the density of each sample was calculated using the ratio of sample mass to volume. The results showed that the acoustic properties of the sound speed, acoustic attenuation, and impedance of the PVA samples were in the range of 1598.14 ± 8.25 – 1893.27 ± 6.57 ms−1 at a frequency of 1 MHz, 0.61 ± 0.076 – 0.67 ± 0.195 dB cm−1 MHz−1, and 1.67 – 2.23 (106 kg m−2 s−1). While the elasticity and density properties of PVA samples had a range of 7.87 ± 0.084 – 81.56 ± 1.094 kPa, 1.046 – 1.176 g cm−3. In conclusion, the PVA samples have excellent soft tissue equivalence based on acoustic and mechanical properties. The material composition of this finding can be used as a reference for the fabrication of ultrasound phantoms for testing device performance or education. [ABSTRACT FROM AUTHOR]

Combinations of various types and structures of materials were developed to obtain highest sensitivity of biosensor. The optical analysis of the electric field simulation results was used to determine the best arrangement of thin layer and nanostructures Au and Ag electrodes as an optical biosensor for blood cancer detection. This study used a finite difference time domain (FDTD) to simulate the electric field distribution and analyze the optical properties of the biosensor. This research was conducted by making an anodic aluminum oxide (AAO) as mold of a nanostructure whose hole dimensions will be used as a model of the nanostructure in the simulation. The holes in AAO are circles with a diameter of 90 nm and the distance between holes is 25 nm. The structural model for electric field simulation is a glass substrate coated with an Ag thin film/Au nanostructure, Au thin film/Ag nanostructures, arrays of Ag/Au nanostructures, and arrays of Au/Ag nanostructures. The top side of the nanostructure arrangement and thin film will be deposited with normal blood cells and leukocytes. The electric field distribution shows that the Ag thin film/Au nanostructure is the best combination electrode of nanostructures and thin film of Ag and Au for the detection of blood cancer because of the highest difference of absorbance intensity and absorbance peak wavelength, which is 8.66 nm. These results provide a preliminary interpretation of the arrangement of nanostructures and thin film of gold and silver for optical blood cancer detection as biomedical device. [ABSTRACT FROM AUTHOR]

Electrical Impedance Tomography (EIT) is a non-invasive measurement technique to obtain reconstructed images based on impedance properties. The use of EIT in the medical field has been widely applied including in the detection of brain abnormalities. In this study, EIT was developed for head-brain imaging in which particularly to detect abnormalities in the brain and it was simulated with Electrical Impedance Tomography and Diffuse Optical Tomography Reconstruction Software (EIDORS). There are three processes carried out in the reconstruction of the head-brain image. These processes are namely determining the Finite Element Method (FEM) model and creating strange objects or anomaly inclusion, applying the IRLS algorithm to obtain an inversion solution, and segmenting the anomaly inclusion with k-means clustering. The results of EIT image reconstruction and evaluation with Structural Similarity Indices (SSIM) and Image Correlation Coefficient (ICC) show that the proposed method is able to obtain head-brain images with promising results. [ABSTRACT FROM AUTHOR]

Deep Learning for analyzing medical images in thoracic diseases is considered necessary in radiology. The thorax examination is the most frequently performed examination in routine examinations. Analytical methods that can explain medical image analysis finding morphological patterns or textures in images are urgently needed. Currently, the interpretation of the thorax is carried out manually by radiologists based on thorax images that are influenced by the cognitive abilities and subjective experience of radiologists, thus allowing human error to occur in reading or analyzing. This study aimed to classify chest diseases such as Edema, Pneumonia, and Pneumothorax using a Convolutional NeurXR) image data used to determine chest disease are normal, edema, pneumonia, and pneumothorax data of 1487, 1022, 1374, and 1128 with an image size of 200×200 pixels. This study also analyzed optimizers RMSprop, Adadelta, Adagrad, Adamax, and Adam in the classification of thorax disease for the CNN algorithm. The results showed that Adam is the best optimizing parameter and can show good accuracy of more than 98% for the classification of thorax diseases such as Edema, Pneumonia, and Pneumothorax with epochs equal to 10. [ABSTRACT FROM AUTHOR]

The biologically based limiting factor in optimizing the radiotherapy planning process allows the establishment of dose distribution by balancing the amount of volume received at different dose levels between the target and organs at risk. In planning treatment, to optimize the dose at the target and minimal to the organs at risk (OARs), it is necessary to have a generalized Equivalent Uniform Dose (gEUD) factor in Treatment Planning System (TPS). This study aims to evaluate the radiobiological effect using the IMRT technique. Normal Tissue Complication Probability (NTCP), Tumor Control Probability (TCP), and Homogeneity Index (HI) in oropharyngeal cancer cases were also investigated. In addition, the aimed study was to compare clinical TPS dose calculation with TPS simulation with PRIMO software. DICOM patient data comes from the Cancer Imaging Archive (TCIA) with the code HNSCC-01-0002. The radiobiological analysis of the probability of normal tissue complications based on NTCP parameters was obtained close to 0% for all OARs, whereas the probability of tumor control was 100%. Meanwhile, the dose distribution homogeneity was almost homogeneous due to the value being close to zero. Similar dose distribution patterns were obtained when the clinical TPS compared to the TPS simulation with PRIMO. [ABSTRACT FROM AUTHOR]

The use of radiotherapy as a cancer treatment modality is growing very rapidly. One of the cases of head-neck cancer is nasopharyngeal cancer which was performed using the Intensity Modulated Radiotherapy (IMRT) technique. This study aims to evaluate the target and organs at risk (OARs) absorption dose using PRIMO and DICOM TCIA HNSCC-01-0190 data with IMRT technique number of fields 9 using a photon energy of 6 MV. Data Data is processed using PRIMO software to obtain DVH data. The Gamma analysis method with acceptance criteria of 3%, 3 mm, was used to compare dose distribution. The validation of the PRIMO dose calculation shows a minimum gamma analysis pass of 83%. From the research results obtained, Percentage Aggregation (PA) has a value of more than 90%. It shows that PRIMO can validate the treatment planning system using variations in the number of fields. [ABSTRACT FROM AUTHOR]

Radiotherapy helps kill cancer cells in patients. In the radiotherapy process, radiation quality assurance is needed to maintain consistency and safety in administering doses to the target. The implementation of radiotherapy in patients requires planning made by medical physicists. In this study, radiotherapy treatment planning was carried out using the 3D Slicer-SlicerRT in the case of lung cancer with the diagnosis of stage II squamous cell carcinoma, male sex and consisted of 1 nodule. Patient data is obtained from The Cancer Imaging Archive, NSCLC-Radiomics. The method in this study began with processing patient data with a total fraction recipe of 60 Gy/30 and 63 Gy/30. The variations given are combination gantry angles of 0°,45°,90°,135°,180°, and 225°, with the number of beams being 4, 5, and 6. Furthermore, the value of the homogeneity index, tissue density, and electron density was evaluated. Dosage planning is limited to 95−107% of the dosage determined based on the ICRU 50. This study obtained the results of tissue density and electron density relatively by the reference standards for each organ. The treatment planning results are by the total standard and have the best homogeneity index of 0.25449 for five beams. [ABSTRACT FROM AUTHOR]

Radiation dose is the basis used to optimize lung cancer treatment, requiring the right and accurate amount. One of the steps used in optimizing treatment is radiotherapy treatment planning, which aims to maximize the dose targeted at tumor cells and minimize the dose to healthy organs. This study aims to evaluate the fulfillment of total dose standards for healthy organs and the homogeneity of dose distribution using the 3D slicer-Slicer RT software. The method used in this study used two CT data and RT-Structures of NSCLC-Radiomics with a diagnosis of stage IIIB squamous cell carcinoma from The Cancer Imaging Archive (TCIA), the exact location of cancer, and only one nodule. Network density values are calculated using segment statistics on 3D Slicer based on CT-DICOM information. Meanwhile, the treatment plan was built using 3D Slicer-SlicerRT with a 60 Gy/30 fraction dose. The treatment design uses four planes, and optimization combines the gantry angle and beams weight. The results showed that the treatment planning system using 3D Slicer-SlicerRT met the total dose standard for healthy organs and had a homogeneity index for the first and second patient was 0.004 and 0.009, respectively. [ABSTRACT FROM AUTHOR]

The ease of manufacturing human phantoms using 3D printing technology is a breakthrough for quality assurance tools in radiotherapy and diagnostic radiology with a more accessible and more cost-effective technique. However, a challenge arises to identify suitable materials and achieve cancer tissue equivalency. This study evaluates the characteristics and determines the appropriate material to mimic cancer tissue in a 3D anthropomorphic phantom. The material samples consisted of agar, gelatin, agarose, polyester resin, and silicon rubber. All samples were synthesized and printed into a cylindrical mold made of 95% polylactic acid (PLA) with a diameter of 3 cm and thickness of 1 cm. Calcium powder (Ca), salt (NaCl), and silica gel (SiO2) were added to some materials to expand the range of CT number or Hounsfield Unit (HU) values to adjust the attenuation characteristics of the actual cancer tissue. The material samples were tested with CT scan equipment, and the HU value was measured using RadiAnt DICOM Viewer software. The results obtained that agar, gelatin, and agarose material have an average HU value in the same range as the actual cancer tissue, namely 4 to 47, 14 to 31, and-19.47 to 21.84 HU, respectively. This agreement is further confirmed by relative electron density (RED) values for agar, gelatin, and agarose materials of 1.03, 1.02, and 1.00, respectively. These RED values are equal to the actual RED value of cancer tissue, which is 0.99. Besides, this study also evaluates the CT image quality and HU value of material based on tube voltage variation. The results show that the average HU value on the CT image gives a less significant difference and has a small variation in the HU range from 80 to 140 kV voltage. Therefore, it can be concluded that agar, gelatin, and agarose can be used as mimic materials of cancer tissue, and the HU value is not significantly affected by the tube voltage variation factor. [ABSTRACT FROM AUTHOR]

Imaging modalities such as Computed Tomography (CT) are one of the technologies to produce high-resolution images. The image generated by CT can be used to diagnose diseases in patients. CT may also be required during pregnancy to determine common causes of acute abdominal pain such as suspected appendicitis, intestinal obstruction, and pancreatitis, especially if other imaging techniques such as ultrasound and magnetic resonance imaging (MRI) are inconclusive. For chest-abdomen-pelvic (CAP) CT examination, the possibility of the fetus being directly irradiated, so potential exposure to the fetus should be considered. The aimed study evaluated the dose received by the fetal during CT scan using IndoseCT software. IndoseCT is software for calculating and managing the radiation dose of computed tomography. The maximal dose received by the fetal is 50 mGy based on NCRP Report 128. This study uses three patient CT scan images on The Cancer Genome Atlas Uterine Corpus Endometrial Carcinoma (TCGA-UCEC) data obtained from The Cancer Imaging Archive (TCIA). The equivalent dose is calculated in the area of fetal growth. From the simulation, the values of CTDIvol, Dw, SSDE, and the effective dose will be displayed based on AAPM Report 204. The dose obtained in the area around the fetal growth in all three data was below the threshold. [ABSTRACT FROM AUTHOR]

The second most frequently diagnosed cancer (11.4%) is lung cancer and the leading cause of cancer death (18%). Radiation planning is a stage in radiation treatment. The purpose of radiation planning is to provide the maximum dose to the target tumor and minimize the dosage received by the organ at risk (OAR). Therefore, it is necessary to make a treatment plan, and dose analysis was to determine radiation characteristics using a 3D Slicer. This study used three patient data on stage IIIB (large-cell) Non-Small Cell Lung Cancer obtained from The Cancer Imaging Archive (TCIA). This research uses 3D Slicer software. Relative Electron Density (RED) was obtained from the segment statistics module and radiation planning using the radiotherapy module. The study analyzes the Relative Electron Density, the target volume, the OAR, and homogeneity with the reference. The mean values of RED in the spinal cord, left lung, right lung, esophagus, and GTV-1 were 1.148, 0.244, 0.231, 0.629, and 0.691, respectively. The iso levels have values above 95% and less than 100%. The obtained radiation dose by organs at risk in all patients is still below the tolerance limit of the recommendation. The HI values of the three IDs are homogeneous. [ABSTRACT FROM AUTHOR]

EBT3 radiochromics film is a dosimeter commonly used in radiation oncology because it has properties equivalent to tissue or water, high spatial resolution, low dependence on energy and dose. Consequently, the accuracy and precision during the dose reading procedure of the EBT3 must be excellent accomplished during radiation therapy treatment. The objective was to evaluate the dosimetry of the EBT3 radiochromic using the transmission and reflection mode scanning method for radiation therapy. This study used an EBT3 radiochromic film with a size of 2.5×3 cm² and irradiated with 6 MV photons and 6, 8, 10, 12, and 15 MeV electrons. The EBT3 film irradiation process used a surface axis distance (SAD) of 100 cm, solid water phantom for the scattering medium, and an irradiation field of 10×10 cm². Each EBT3 film was irradiated using prescribed energy at doses of 0, 100, 200, 300, 400, 500, 600, and 700 cGy. The digitalization process of EBT3 film used an Epson V850 Pro flatbed with a resolution of 72 dpi, 48-bit RGB, no correction color, using reflection and transmission modes. The pixel value reading of the EBT3 film used Image-J to obtain a calibrating curve for EBT3 film in each photon and electron energy range. The results showed that the transmission mode had a higher accuracy than the reflection mode for all dose and energy ranges, while the reflection mode had a higher sensitivity than the transmission mode. [ABSTRACT FROM AUTHOR]

Radiation therapy treatment for post-mastectomy breast cancer usually requires a bolus to raise the surface dose to a certain level. Bolus is a compensatory material that has properties such as soft tissue or water. Therefore, this study will evaluate the potential of using bolus and without bolus in post-mastectomy breast cancer cases. This study aims to analyze the percentage surface dose (PSD) on the solid water slab phantom, dose-volume histogram (DVH), profile dose, and surface dose in Postmastectomy Radiation Therapy (PMRT) cases with and without using a bolus made of silicone rubber with a thickness of 0.5 cm. The methods used in the present study involving measuring surface dose using bolus and without bolus on a solid water slab phantom with the TRS 398 protocol, making an Intensity-modulated radiation therapy (IMRT) planning system in 5 fields with angles of 30˚, 60˚, 230˚, 260˚and 320˚. Then analyzed DVH, dose profile, and surface dose using bolus and without bolus. Finally, verification of the plans that have been made is done using EBT3 film placed at 3 points (isocenter, right, and left). The results showed that DVH with bolus and without bolus met the recommendations of the International Commission on Radiation Unit (ICRU) 62, and organ at risk (OAR) still met the tolerance limit. The percentage of surface dose reached 80.02 % and 29.75 %, respectively, for with and without bolus. The surface dose in PMRT increased up to 35%. Moreover, a bolus can increase the dose to the surface very well when the tumor cells are located on the surface compared to without a bolus. [ABSTRACT FROM AUTHOR]

Linear Accelerator (LINAC) is one of the devices that is often used in external radiation treatment. Photon radiation treatment with targets near the surface results in a poor distribution of doses. Therefore, the use of a substitute tissue-equivalent increases the surface dose of the skin. The study aimed to evaluate the use of the bolus with silicone rubber and silica gel (SRS) to increase the surface dose and determine the percentage difference in a surface dose between measurement and treatment planning systems (TPS). Bolus was fabricated with 11×11 cm2 and a thickness of 0.5 cm and was irradiated by photon energy of 6 MV. The value of a surface dose is measured using an EBT3 film dosimeter using the Three Dimensional Conformal Radiotherapy (3D-CRT) technique. Based on the distribution test of dose on a bolus with a water slab phantom, the surface dose can be increased compared to no bolus with a value of 86.64%. Meanwhile, the percentage difference in surface dose on the thorax phantom between TPS and direct measurements showed a value above 10%. Some suggestions when using film dosimeters require specific designs and markings for placing the film in certain areas to prevent dose verification errors. [ABSTRACT FROM AUTHOR]