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"PET scanner dikenal secara luas dalam pencitraan klinis untuk menentukan abnormalitas deteksi lesi kecil. Dalam studi ini, dilakukan evaluasi deteksi objek lesi menggunakan solid fantom in-house. Pengukuran dilakukan dengan menggunakan phantoms in-house dalam bentuk silinder lingkaran dan elips dengan objek lesi berdiameter 6 mm dan konsentrasi aktivitas FDG yang bervariasi. Lebih lanjut, dilakukan pula pengukuran objek lesi  dengan ukuran 6-, 8-, 11-, 16-, and 21 mm yang berada dalam phantoms silinder elips dengan material ekuivalen paru dan liver, berturut-turut dengan ukuran major dan minor axis, (33 × 18 cm) dan (28×20 cm). Objek lesi dilakukan variasi posisi secara sejajar dan melingkar. Evaluasi citra PET dilakukan perhitungan untuk menentukan Full Width Half Maximum (FWHM) berdasarkan protokol National Electrical Manufacturing Association (NEMA), dan selanjutnya menghitung Conversion Factor FWHM (CFh), serta menggunakan Fitting Gaussian. CFh merupakan rasio antara ukuran objek aktual dan citra FWHM. FWHM dalam sumbu x dan sumbu y berkisar antara 7,61 hingga 10,68 untuk 6 mm; 8,41 hingga 10,94 untuk 8 mm; 9,59 hingga 11,20 untuk 11 mm; 12,59 hingga 14,43 untuk 16 mm; 16,77 hingga 18,61 untuk 21 mm. Dengan hasil menunjukan CFh dipengaruhi oleh ukuran objek lesi di dalam phantom silinder elipse dengan material ekuivalen paru-paru dan hati yang. Citra PET  10 mm diperoleh nilai FCF  1.00 menunjukan ukuran objek sebenarnya lebih kecil dari ukuran citra. Citra PET hampir tidak mengalami perbesaran apabila citra PET mendekati 10 mm. Untuk citra PET 10 mm ditunjukan oleh nilai FCF  1.00, yang berarti ukuran objek sebenar lebih dari ukuran citra.

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PET scanner is widely known in clinical imaging to determine small lesions. We evaluated the detection of lesion object using solid-phantom in-house. Measurement was performed using in-house phantoms ellipse with carried out sizes of lesion object 6-, 8-, 11-, 16-, and 21 mm in lung and liver equivalent material. The lesion object was arranged in different position of parallel and circular.  Evaluation of PET image was calculated to determine the Full Width Half Maximum (FWHM) based on National Electrical Manufacturing Association (NEMA) protocol, and furthermore to calculate Conversion Factor FWHM (CFh), which represents the ratio between the size of the actual object and FWHM profile image.

The FWHMs in x-axis and y-axis were range 7.61 to 10.68 for 6 mm; 8.41 to 10.94 for 8 mm; 9.59 to 11.20 for 11 mm; 12.59 to 14.43 for 16 mm; 16.77 to 18.61 for 21 mm. With the result that the CFh was affected by the size of lesion object inside the ellipse cylinder phantom with lung and liver equivalent. PET image is size <10 mm obtained CFh value <1.00, it indicates that the actual object size is smaller than the image size. The PET image was barely enlarged if the PET image approaches 10 mm. PET images >10 mm was indicated by the CFh value >1.00, which means the object size was actually higher than the image size."

"Pengecekan akurasi kualitas citra dalam program kontrol kualitas quality control, QC dapat ditingkatkan dengan penggunaan fantom yang mendekati kondisi realistis pada pemindaian klinis. Penelitian ini ditujukan untuk mengembangkan fantom desain khusus yang terdiri dari material organik ekuivalen-hati dan otot jaringan lunak . Karakterisasi sifat radiologi material ekuivalen jaringan menunjukan bahwa material ekuivalen jaringan lunak otot yang tersusun atas campuran Gondorukem, Malam Cecek, dan tepung beras dengan rasio massa 70/20/10 memiliki CT Number -20.27 0.33 HU, densitas massa 1.055 g/cm3 dan densitas elektron 3.461 1023 e/m3. Material ekuivalen jaringan hati yang tersusun atas campuran Malam Cecek dan tepung beras dengan rasio massa 60/40 memiliki CT Number 74.17 1.48 HU, densitas massa 1.024 g/cm3 dan densitas elektron 3.396 1023 e/m3. Penggunaan fantom desain khusus dalam mengevaluasi kualitas citra PET berdasarkan parameter full-width-half-maximum FWHM resolusi dan signal-to-noise ratio SNR menunjukan bahwa detektabilitas sistem pemindaian PET bergantung terhadap ukuran pixel dan metode rekonstruksi citra yang digunakan. Sistem pencitraan PET/CT Siemens Biograph dengan rekonstruksi True-X dan filter Butterworth menggunakan ukuran pixel 1 x 1 mm2, memberikan ukuran obyek pada citra PET lebih kecil daripada ukuran obyek sebenarnya, kecuali pada obyek 4.02 mm. Sistem pemindaian PET/CT Philips Gemini TOF 16 dengan ukuran pixel 4 x 4 mm2 menunjukan adanya perbesaran ukuran obyek kecil dengan diameter kurang dari 16 mm. Kedua pesawat PET/CT menunjukan bahwa ukuran obyek pada citra cenderung lebih kecil atau mencapai threshold 80 dari ukuran sebenarnya pada obyek berdiameter lebih besar sama dengan 16.30 mm. Sebaliknya, overestimation nilai FWHM terjadi pada obyek berukuran kecil 4.20 mm sebagai akibat dari terjadinya partial volume effect. Studi pengukuran kualitas citra dengan fantom desain khusus ini menunjukan bahwa pemilihan metode rekonstruksi, filter post processing, dan ukuran pixel mempengaruhi resolusi atau detektabilitas dan SNR pada citra PET. Pada akhirnya, fantom desain khusus ini mampu memberikan analisa kualitas.

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The purpose of this research was to develop a phantom for quality control QC of PET CT image quality. The phantom was constructed by tissue equivalent materials which consist six cylindrical hot lesions with diameter of 4.20, 6.20, 8.30, 9,80, 16.30, and 19.00 mm. Wax and rice starch were combined to produce the tissue equivalent materials. The results showed that combination 70 20 10 of gondorukem cecek wax rice starch and 60 40 of cecek wax rice starch yielded liver and muscle surrogate materials respectively. Liver equivalent material LEM was 74.17 1.48 HU, 1.024 g cm3 of mass density, and 3.396 1023 e m3 of electron density. While, muscle equivalent material MEM was 20.27 0.33 HU, 1.055 g cm3 of mass density and 3.461 1023 e m3 of electron density.

Then, the phantom was scanned using two different PET CT scanner to determine the detectability and signal to noise ratio SNR as measure PET CT imaging performance. It showed that the detectability of PET CT scanner was affected by pixel size and reconstruction method for image acquisitions. For Siemens Biograph PET CT scanned using pixel sixe of 1 1 mm2, FWHMs were smaller than the actual size of the hot lesions. Meanwhile, for Philips Gemini PET CT scanned using pixel sixe of 4 4 mm2, FWHMs were larger than the actual size of the hot lesions.

For both PET CT scanner, ratio of FWHM actual size reached the threshold of 80 at object diameter ge 16.30 mm. In contrast, overestimation of FWHM occurred at smaller object diameter 4.20 mm significantly caused by the partial volume effect. The study also indicated that image reconstructions, post processing smoothing filter, and pixel size may give impact to the detectability and SNR performed by a PET CT system. It was concluded that the phantom could be used to analyze the image quality performance in PET CT imaging."

"The horizons of sophisticated imaging have expanded with the use of combined positron emission tomography (PET) and computed tomography (CT). PET-CT has revolutionized medical imaging by adding anatomic localization to functional imaging, thus providing physicians with information that is vital for the accurate diagnosis and treatment of pathologies. Since the integration of PET and CT several years ago, PET/CT procedures are now routine at leading medical centers throughout the world. This has increased the importance of nuclear medicine physicians acquiring a broad knowledge in sectional anatomy for image interpretation. The Atlas of Sectional Radiological Anatomy for PET/CT is a user-friendly guide presenting high-resolution, full-color images of anatomical detail and focuses solely on normal FDG distribution throughout the head & neck, thorax, abdomen, and pelvis, the primary sites for cancer detection and treatment through PET/CT."

"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."

"PET-CT is increasingly being employed in the diagnosis of both oncological and non-oncological patients, yet nuclear medicine physicians may have only limited practical experience of rare diseases and may experience difficulty in recognizing and interpreting rare findings. This unique atlas documents a large number of clinical cases that will help practitioners to identify findings and diseases that, though rare, are sufficiently frequent to be encountered in routine practice. Two types of cases are presented: patients evaluated for rare diseases and patients evaluated for standard diseases in whom atypical PET findings were detected. Each reported case includes a brief description of the clinical history, representative color PET-CT images obtained using FDG or other tracers, and a short explanation of the disease and findings. "

"We developed a gamma ray detector with an LuAG:Pr scintillator and an avalanche photodiode as a detector for a positron emission tomography (PET) system. Studies have been performed on the influences of gamma irradiation on application-specific integrated circuit (ASIC) preamp boards used as a detector module. As a device used in nuclear environments for substantial durations, the ASIC has to have a lifetime long enough to ensure that there will be a negligible failure rate during this period. These front-end systems must meet the requirements for standard positron emission tomography (PET) systems. Therefore, an equivalent noise charge (ENC) experiment is needed to measure the front-end system's characteristics. This study showed that minimum ENC conditions can be achieved if a shorter shaping time could be applied."

"Computed Tomography (CT) Scanner merupakan alat pencitraan diagnostik yang memberikan informasi citra medis untuk menunjang pengobatan pasien, namun tanpa disadari pemanfaatan radiasinya dapat menimbulkan efek negatif pada organ sensitif sekitar. Penelitian ini dilakukan untuk mengukur dosis organ sensitif (mata, tiroid, dan payudara) menggunakan fantom Rando pada CT Scanner area thorax. Untuk memudahkan penelitian ini, TLD rod 100 digunakan sebagai dosimeter, dimana kV dan pitch dijadikan sebagai variasi parameter penelitian. Hasil menunjukkan bahwa nilai paparan dosis tertinggi pada tiap kualitas berkas berturut-turut dari 80, 120, dan 140 kV yaitu payudara kanan (1,72±0,34 mGy), tiroid kanan (6,25±0,16 mGy), dan payudara kiri (10,78±0,76 mGy). Pada variasi pitch nilai paparan dosis tertinggi secara berturut-turut dari 4, 6, dan 8 yaitu payudara kiri (6,19±0,02 mGy), tiroid kanan (6,25±0,16 mGy), dan payudara kanan (5,08±0,85 mGy). Dapat disimpulkan bahwa nilai dosis payudara pada CT Thorax lebih tinggi dibandingkan dengan mamografi, namun keduanya tidak melebihi nilai batas dosis yang ditetapkan International Commission on Radiological Protection (ICRP) yaitu 5 Gy.

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Computed Tomography (CT) Scanner is an instrument of medical imaging using radiation to support treatment for patient, but the radiation may give a negative effect around sensitive organs. The research meant to measure dose for sensitive organs at thorax area (eyes, thyroid, and breast) using CT Scanner with rando phantom as an object. To ease this experiment, TLD rod 100 used as dosimetry, which kV and pitch as a parameter variation. The result showed that the highest dose for kV variation upon each sequent beam quality from 80, 120, and 140 kV are right breast (1,72±0,34 mGy), right thyroid (6,25±0,16 mGy), and left breast (10,78±0,76 mGy). Towards pitch variation the highest exposure dose value in sequently from 4, 6, and 8 are left breast (6,19±0,02 mGy), right thyroid (6,25±0,16 mGy), and right breast (5,08±0,85 mGy). As a conclusion, the dose on breast from CT Thorax is higher than the one from mammography but both are bellow dose value limit from International Commission on Radiological Protection (ICRP) which is 5 Gy."

"X-ray computed tomography (CT) has been playing an important role in current medical practice for diagnostic procedure. Beside its delicate technology, the 'hidden' software of CT image reconstruction has contributed almost half of total cost of a CT-scanner unit. Since Algebraic Reconstruction Technique (ART) is a basic to understand an iterative method of CT image reconstruction algortihm, and since it is difficult to find a clear description of fan beam ART algorithm in university literatures, it is important to develop an own algorithm and to begin a basic systematic research of this iterative method. After a long term of trial and error work, the research had succeded in developing an ART algorithm for third generation CT image reconstruction. By comparing the result of the research with more popular technique like Filtered Back Projection (FBP), the algorithm has been proved applicable to reconstruct a low dimension object matrix (32x32 and 64x64). By the resulted computer program, then basically a simple and low cost third generation CT-scanner can be designed for medical physics or biomedical imaging research. Finding a way of shortening the massive number of iterations process then, will be able to open the possibility of using the software for higher object matrix dimensions."

"Computed Tomography Dose Index (CTDI) merupakan konsep utama dalam dosimetri CT scan. Berdasarkan rekomendasi IAEA di TRS 457, CTDI dapat diukur di udara dan di fantom khusus CTDI. Ukuran dan massa fantom cukup besar sehingga akan menyulitkan dalam mobilisasi. Dalam penelitian ini dilakukan pengukuran CTDI untuk mengetahui faktor fantom pesawat Siemens Sensation 64. Faktor fantom adalah perbandingan CTDIw terhadap CTDIair. Fantom yang digunakan adalah fantom berbahan polymethil methacrylic (PMMA) berdiameter 16 cm sebagai fantom kepala dan 32 cm sebagai fantom tubuh. Detektor yang digunakan adalah Xi CT Platinum dan Xi Base Unit sebagai elektrometer. Estimasi dosis efektif dihitung berdasarkan nilai CTDIair pengukuran yang dikoreksi dengan perangkat lunak ImPACT CT Dosimetry Patient Calculator version 1.0.4. Nilai faktor fantom yang diperoleh untuk fantom kepala dan tubuh secara berturut-turut ialah 0.702 dan 0.357. Estimasi dosis efektif satu fase (rata-rata ± deviasi standar) ialah: kepala rutin 2.01 ± 0.11 mSv, kepala trauma 2.53 ± 0.16 mSv, thorak 3.4 2 ± 0.79 mSv, abdomen 5.99 ± 2.16 mSv, dan pelvis 2.12 ± 0.99 mSv. Faktor konversi DLP displai scanner terhadap dosis efektif: kepala rutin 0.0021 mSv/mGy.cm, kepala trauma 0.0022 mGy.cm, thorak 0.0182 mSv/mGy.cm, abdomen 0.0151 mSv/mGy.cm, dan pelvis 0.0118 mSv/mGy.cm.

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Computed Tomography Dose Index (CTDI) is primary dosimetric concept in CT scan. Based on IAEA TRS 457 recommendation, CTDI can be measured free in air and by using phantom. Phantom size and mass are huge, thus it will complicate the mobilization. This research conducted CTDI measurement to find out the Siemens Sensation 64 phantom factor. Phantom factor is a ratio between CTDIw over CTDIair. A Polymethyl Methacrylic (PMMA) phantom was used in this research, which has 16 cm of diameter for head phantom and 32 cm of diameter for body phantom. The Xi CT Platinum detector was used in this research and Xi base unit is as an electrometer. The estimation of effective dose was calculated using CTDIair value and ImPACT CT Dosimetry Patient Calculator version 1.0.4. In this research was found out that the phantom factors are 0.702 for head phantom and 0.357 for body phantom. The estimation of effective dose for one phase (mean ± standard deviation): head routine 2.01 ± 0.11 mSv, head trauma 2.53 ± 0.16 mSv, thorax 3.4 2 ± 0.79 mSv, abdomen 5.99 ± 2.16 mSv, and pelvis 2.12 ± 0.99 mSv. DLP on scanner display to effective dose conversion factors: head routine 0.0021 mSv/mGy.cm, head trauma 0.0022 mSv/mGy.cm, thorax 0.0182 mSv/mGy.cm, abdomen 0.0151 mSv/mGy.cm, and pelvis 0.0118 mSv/mGy.cm."

""The book offers a comprehensive and user-oriented description of the theoretical and technical system fundamentals of computed tomography (CT) for a wide readership, from conventional single-slice acquisitions to volume acquisition with multi-slice and cone-beam spiral CT. It covers in detail all characteristic parameters relevant for image quality and all performance features significant for clinical application. Readers will thus be informed how to use a CT system to an optimum depending on the different diagnostic requirements. This includes a detailed discussion about the dose required and about dose measurements as well as how to reduce dose in CT. All considerations pay special attention to spiral CT and to new developments towards advanced multi-slice and cone-beam CT. For the third edition most of the contents have been updated and latest topics like dual source CT, dual energy CT, flat detector CT and interventional CT have been added. The enclosed CD-ROM again offers copies of all figures in the book and attractive case studies, including many examples from the most recent 64-slice acquisitions, and interactive exercises for image viewing and manipulation. This book is intended for all those who work daily, regularly or even only occasionally with CT: physicians, radiographers, engineers, technicians and physicists. A glossary describes all the important technical terms in alphabetical order. The enclosed DVD again offers attractive case studies, including many examples from the most recent 64-slice acquisitions, and interactive exercises for image viewing and manipulation"--Back cover."