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"Computed tomography (CT) is a powerful technique providing precise and confident diagnoses. The burgeoning use of CT has resulted in an exponential increase in collective radiation dose to the population. Despite investigations supporting the use of lower radiation doses, surveys highlight the lack of proper understanding of CT parameters that affect radiation dose. Dynamic advances in CT technology also make it important to explain the latest dose-saving strategies in an easy-to-comprehend manner. This book aims to review all aspects of the radiation dose from CT and to provide simple rules and tricks for radiologists and radiographers that will assist in the appropriate use of CT technique. The second edition includes a number of new chapters on the most up-to-date strategies and technologies for radiation dose reduction while updating the outstanding contents of the first edition. Vendor perspectives are included, and an online image gallery will also be available to readers."

"Fetus in fetu (FIF) adalah kelainan kongenital yang jarang ditemukan, muncul 1 dari 500 000 kelahiran dengan perbandingan laki-laki lebh banyak 2:1. Lebih dari 80 kasus telah dilaporkan dalam literatur dengan lokasi yang bervariasi mulai dari retroperitoneal dan intraperitoneal yang tersering sampai ke intracranial, intraoral dan intrascrotal. Tanda penting FIF yang dapat ditemukan secara radiologis adalah ditemukannya massa kistik jaringan lunak dengan komponen padat di dalamnya yang berbentuk seperti fetus dan memiliki organ-organ dengan diferensiasi yang tinggi antara lain seperti ditemukannya vertebra, tulang panjang, kranium, usus, ekstremitas, jari-jari, dll. Secara radiologis FIF penting untuk dibedakan dengan Teratoma karena kemungkinan untuk terjadinya keganasan lebih tinggi dan operasi eksisi massa perlu dilakukan secepatnya pada teratoma.

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AbstractFetus in fetu (FIF) is a rare congenital anomaly, appear 1 in 500 000 births, with male to female ratio of 2:1. More than 80 cases have been reported in the literature with varied locations ranging from the most common retroperitoneal and intraperitoneal to intracranial, intraoral and intrascrotal. Essential signs that can be found in the FIF is a large cystic mass with a complex solid component inside with a fetusform and have organs with high differentiation such as the the vertebrae, long bones, skull, intestine, limb, fingers, etc. It is radiologicaly important to distinguish FIF with teratoma because of the possibility for the occurrence of malignancy and mass excision surgery should be done as early as possible for teratomas."

"This book provides a lucid summary of modern multislice CT imaging of the abdomen, with a focus on the essential imaging findings. After a concise technical introduction, the most important abdominal diseases are described and illustrated with high-quality images. Sections are devoted to the liver and biliary system, the pancreas and spleen, the kidneys and urogenital system, and the bowel and peritoneal cavity. Throughout, key differential diagnostic features are highlighted. The editorial team is composed of internationally renowned radiologists from Europe and the United States, and all chapters have been written by recognized experts in the topic under consideration. Multislice CT of the Abdomen will serve as an excellent reference for radiologists participating in further professional training and will prove an ideal source of information for all who wish to deepen their personal knowledge of the subject."

"Dalam pemanfaatan radiasi pengion khususnya di bidang medis, sinar - x sangat berperan sekali dalam proses penegakan diagnosa. namun dalam penggunaanya harus dilandasi dengan prinsip ALARA (as low as reasonably achievable), yakni bahwa suatu nilai paparan dosis radiasi yang diterima didalam pemanfaatan sinar-x adalah harus sekecil mungkin dan dapat dipertanggung jawabkan. Sesuai dengan ketentuan BAPETEN Pemeriksaan radiologi seharusnya pada ruang tertutup dan telah di lengkapi oleh sistem proteksi radiasi. Pada hasil observasi di Rumah Sakit X bahwa terdapat pemeriksaan radiografi di unit Intensive Care Unit dan tidak terdapat sistem proteksi radiasi hal ini tidak sesuai dengan ketentuan BAPETEN. Maka Tujuan dari penelitian ini adalah untuk mengetahui jarak aman terhadap dosis radiasi hambur yang ditimbulkan dari pemeriksaan radiografi tersebut. Penelitian ini menggunakan metode kuantitatif dengan pendekatan cross sectional. Hasil Penelitian ini menunjukan bahwa pada radius jarak 100, 200, 300, 400, centi meter jika melakukan pemeriksaan radiografi Thorax AP di Unit ICU Tanpa Proteksi radiasi dinyatakan tidak aman karena melebihi Nilai Ambang Batas ( NBD) BAPETEN yaitu 0.001 mSv/h. Selain petugas radiographer dilarang berada di ruangan pada saat pemeriksaan. Pemeriksaan radiografi Thorax AP di ICU sebaiknya menggunakan kaidah proteksi radiasi yaitu Jarak, Perisai , dan Waktu.

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In particular the use of ionizing radiation in the medical field, x - ray was instrumental in the process of establishing the diagnosis at all. But its use should be based on the principle of ALARA (as low as reasonably achievable), namely, that the value of exposure to the radiation dose received in the use of x-rays is to be as small as possible, and reliable. In accordance with the provisions BAPETEN radiological examination should be in a confined space and have been completed by the radiation protection system. In the observation at Hospital X that there radiographs in the Intensive Care Unit of the unit and there is no system of radiation protection it is not in accordance with the provisions BAPETEN. So the purpose of this study was to determine the safe distance of the scattered radiation dose resulting from radiographic examinations such. This study used quantitative methods with cross sectional approach. The results of this study show that the radius distance of 100 cm, 200 cm, 300 cm, 400 cm, at the time of Thorax AP radiographs in the ICU Unit without Radiation protection declared unsafe because it exceeds the Threshold Limit Value (TLV) BAPETEN the 0.001 mSv / h. Besides radiographer officers banned from the room at the time of inspection. Thorax AP radiographs in the ICU should use the principles of radiation protection are distance, shielding, and time."

"Teknik Cone Beam Computed Tomography (CBCT) dalam pemindaian 3DRA menggunakan sinar-X berbentuk kerucut bulat atau persegi panjang dengan rotasi pemindaian yang tidak mencapai 360 derajat. Sementara itu, metode perhitungan dosimetri 3DRA saat ini masih mengacu pada konsep CTDI, hal ini mungkin tidak sesuai untuk dosimetri CBCT karena sudut pancaran cone yang lebih besar dibandingkan dengan sudut pancaran fan beam dan rotasi pemindaian 3DRA yang tidak mencapai 360 derajat. Penelitian ini bertujuan untuk menganalisis distribusi dosis pada simulasi dan pengukuran dalam pemindaian Angiografi Rotasi Tiga Dimensi (3DRA). Metode yang digunakan melibatkan perbandingan hasil simulasi distribusi dosis menggunakan perangkat lunak EGSnrc dengan hasil pengukuran pada pesawat Angiografi Phillips Allura FD20 (tiga mode pemindaian) menggunakan bilik ionisasi. Proses simulasi menggunakan perangkat lunak EGSnrc terdiri dari tiga tahap. Pertama, lima fantom CTDI virtual dibuat untuk merepresentasikan lubang sesuai dengan penempatan dosimeter pada posisi yang berbeda (pusat, arah jam 3, 6, 9, dan 12). Ukuran voxel fantom disesuaikan menjadi 1 × 1 × 1 mm². Tahap kedua melibatkan pemodelan dan simulasi tabung sinar-X pada sistem 3DRA menggunakan perangkat lunak BEAMnrc. Terakhir, dilakukan simulasi penyinaran pada fantom virtual menggunakan perangkat lunak DOSXYZnrc. Jumlah histories untuk simulasi ditetapkan menjadi 2.5×108, nilai energi cutoff diatur pada 0,521 MeV untuk transportasi elektron, dan 0,001 MeV untuk transportasi foton. Hasil penelitian menunjukkan bahwa area yang paling banyak terpapar radiasi pada ketiga mode 3DRA terletak pada arah jam 3, 6, dan 9 dari fantom. Nilai akurasi tertinggi didapatkan pada mode Xper CT Cerebral HD pada posisi pengukuran pusat dengan nilai presentase perbandingan sebesar 0,9%, sementara nilai akurasi terendah didapatkan pada mode Xper CT Cerebral LD pada posisi pengukuran arah jam 6 dengan nilai prensentase perbandingan sebesar 647,3%.

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Cone Beam Computed Tomography (CBCT) in 3D rotational angiography (3DRA) uses cone-shaped X-ray beams with non-360 degrees rotation. However, current dosimetry calculation methods for 3DRA, which are based on CTDI formalism, may not be suitable due to the larger cone beam angles compared to fan beam angles and the rotation of 3DRA being not a full 360-degree rotation. This study aims to analyze the dose distributions in simulations and direct measurements in 3DRA scans. The method involves comparing the simulation results of dose distributions using EGSnrc software with direct measurements Philips Allura FD20 angiography (in three preset modes) using a head CTDI phantom and an ionization chamber. To analyze the dose distributions in 3DRA, five virtual CTDI phantoms are generated to represent holes corresponding to the placement of dosimeters at different positions (at center, 3, 6, 9, and 12 o'clock). The voxel size of the phantoms is adjusted to 1×1×1 mm². The modeling and simulation of the X-ray tube in the 3DRA system using the BEAMnrc software. The DOSXYZnrc software is used to simulate the irradiation on the virtual phantom. The simulation is performed with 2.5×108 histories, and the energy cutoff value is set at 0.512 MeV for electron transport and 0.001 MeV for photon transport. The results show that the areas most exposed to radiation in all three preset modes of 3DRA are located on the sides and bottom (at 3, 6, and 9 o'clock) of the phantom. The highest accuracy value was obtained in the Xper CT Cerebral HD mode at the center position with a percentage comparison value of 0.9%, while the lowest accuracy value was obtained in the Xper CT Cerebral LD mode at the 6 o'clock position with a percentage comparison value of 647.3%."

"Latar Belakang: Kasus keganasan pada regio abdominopelvis memerlukan tatalaksana radiasi. Alat imobilisasi membantu untuk meminimalisasi pergeseran lapangan radiasi yang terdiri dari systematic error dan random error. Pada penelitian ini dilakukan perbandingan alat imobilisasi penyangga lutut dan masker pelvis termoplastik. Tujuan: Mengetahui adakah perbedaan tingkat akurasi radiasi kedua imobilisasi yang akan menentukan margin PTV terbaik. Metode: Penelitian prospective randomized control trial pada pasien dengan keganasan regio abdominopelvis yang menjalani radiasi April­–Juli 2024. Systematic dan random error didapatkan dari data Treatment Planning System (TPS). Margin PTV dihitung menggunakan rumus van herk. Hasil: Didapatkan 31 pasien yang masuk dalam kriteria inklusi dan eksklusi terdiri dari 15 sampel dengan imobilisasi termoplastik dan 16 sampel dengan penyangga lutut. Margin PTV yang direkomendasikan untuk masker pelvis termoplastik 6.24 mm pada sumbu x (LL), 14,31 mm pada y(CC), dan 3,28 mm pada z(AP). Sedangkan pada penyangga lutut 7.72 mm sumbu x, 11.76 mm sumbu y, dan 5.16 mm sumbu z. Kesimpulan: Pergeseran AP termoplastik lebih baik dibandingkan penyangga lutut sesuai dengan rekomendasi internasional toleransi £ 3mm. Sedangkan untuk CC dan LL tidak ditemukan adanya perbedaan yang signifikan secara statistik.

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Background: The immobilization tool helps to minimize radiation field shifts which consist of systematic errors and random errors. In this study, a comparison of knee wedge immobilization devices and thermoplastic pelvic masks was carried out on the level of accuracy of radiation delivery. Objective: To determine whether there is a difference in the level of radiation accuracy for both immobilizations which will determine the best PTV margin. Methods: Prospective randomized control trial study in patients with malignancies in the abdominopelvic region who underwent radiation April–July 2024. Systematic and random errors were obtained from Treatment Planning System (TPS) data. PTV margin is calculated using the Van Herk formula. Results: There were 31 patients who met the inclusion and exclusion criteria consisting of 15 samples with thermoplastic and 16 samples with knee wedge. The recommended PTV margins for thermoplastic pelvic masks are 6.24 mm in the x-axis (LL), 14.31 mm in y(CC), and 3.28 mm in z(AP). Meanwhile, the knee wedge is 7.72 mm x-axis, 11.76 mm y-axis, and 5.16 mm z-axis. Conclusion: Thermoplastic AP displacement is better than the knee wedge according to international standard tolerance of £ 3mm. Meanwhile, for CC and LL, no statistically significant differences were found."

"Penelitian ini bertujuan untuk melakukan evaluasi dosis titik pada kasus kanker payudara untuk teknik Enhanced Dynamic Wedge (EDW), Forward IMRT, dan Inverse IMRT. Evaluasi ini dilakukan dengan mempertimbangkan pergerakan seperti pergerakan pernafasan manusia. Penelitian ini menggunakan fantom Rando jenis fantom female pada saat TPS untuk mendapatkan nilai CT yang mendekati densitas jaringan tubuh manusia. Selain itu, penelitian ini menggunakan Slab fantom RW3berukuran 30 cm  30 cm  10 cm. Fantom ini akan digunakan utuk pengukuran yang dilakukan pada Linear Accelerator (Linac) dengan mensimulasikan couch dalam keadaan diam dan pergerakan secara translasi pada bidang Anterior Posterior (AP) untuk menirukan pergerakan akibat pernafasan manusia. Pengukuran yang diperoleh berupa dosis titik menggunakan dosimeter thermoluminescence TLD LiF-100. Dari penelitian ini didapatkan pada daerah target, yaitu breast atas dan breast bawah serta daerah Organ at Risk (OAR), persentase dosis terbesar dimiliki oleh teknik EDW pada keadaan dinamik dan persentase dosis terkecil dimiliki oleh teknik Inverse IMRT. Pergerakan anterior posterior memberikan konstribusi terhadap peningkatan persentase dosis pengukuran TLD dengan TPS untuk teknik EDW, Forward IMRT, dan Inverse IMRT berkisar antara 2% sampai 50%.

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This research aimed to evaluate point doses in breast cancer cases for the Enhanced Dynamic Wedge (EDW), Forward IMRT, and Inverse IMRT techniques. The evaluation was conducted considering motion, such as human respiratory motion. The study utilized a female Rando phantom during the Treatment Planning System (TPS) to obtain CT values approximating human tissue density. Furthermore, a 30 cm  30 cm  10 cm  Slab phantom RW3 was used in the research. The phantom was employed for measurements performed on the Linear Accelerator (Linac), simulating a stationary couch and translational motion in the Anterior-Posterior (AP) plane to mimic respiratory-induced motion. Point dose measurements were taken using the LiF-100 thermoluminescence dosimeter (TLD).  From this study, it was found that in the target areas, namely the upper and lower breast regions, as well as the Organ at Risk (OAR) areas, the EDW technique exhibited the highest percentage of dose in dynamic conditions, while the Inverse IMRT technique had the lowest percentage of dose. The anterior-posterior motion contributed to an increase in the percentage of dose measurement differences between TLD and TPS for the EDW, Forward IMRT, and Inverse IMRT techniques, ranging from 2% to 50%."

"Over the past decade, PET-CT has achieved great success owing to its ability to simultaneously image structure and function, and show how the two are related. More recently, PET-MRI has also been developed, and it represents an exciting novel option that promises to have applications in oncology as well as neurology. The first part of this book discusses the basics of these dual-modality techniques, including the scanners themselves, radiotracers, scan performance, quantitation, and scan interpretation. As a result, the reader will learn how to perform the techniques to maximum benefit. The second part of the book then presents in detail the PET-CT and PET-MRI findings in cancers of the different body systems. The final two chapters address the use of PET/CT in radiotherapy planning and examine areas of controversy. The authors are world-renowned experts from North America, Europe, and Australia, and the lucid text is complemented by numerous high-quality illustrations."

"Tujuan penelitian ini adalah untuk melakukan pengukuran CTDI dan dosis efektif pada 3 mesin CT dengan pengujian abdominal terhadap pasien pediatrik dan dewasa menggunakan phantom CT yang dibuat dan detector pensil CT serta electrometer RADCAL. Phantom CT dibuat berdasarkan standar US-FDA untuk CT. Pengujian Computed Tomography (CT) yang dilakukan menggunakan 2 CT phantom yang berbeda, diameter 32 cm (pasien dewasa) dan diameter 16 cm (pasien pediatrik). Pengukuran CTDI dan perhitungan dosis efektif radiasi menunjukkan bahwa terdapat dosis pasien pediatrik yang lebih tinggi signifikan dibandingkan dengan dosis pasien dewasa pada perlakuan yang sama. Hal ini menandakan pentingnya penentuan secara hati-hati parameter teknis scan dan justifikasi yang kuat terhadap penggunaan pengujian CT pada pasien pediatrik.

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A study has been performed to measure CTDI and effective dose on 3 CT machines pertinent to abdominal examination to adult and pediatric patients using fabricated CT phantom and RADCAL pencil detector and electrometer. The CT phantom was tailored according US-FDA standard. Computed tomographic (CT) examinations have been performed using two different CT phantoms, 32 cm (adult) and 16 cm (pediatric) diameter. Computed tomographic (CT) examinations and radiation effective dose showed significant higher pediatric dose as compared to adult patient dose at the same examinations. This indicates the importance of careful selection of technical scan parameters and strong justification of the use of CT examination on pediatric patient."