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Abstrak :
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. ...... 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.

Abstrak :
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.

Abstrak :
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.

Abstrak :
Multidetector-row computed tomography (MDCT) has become a fundamental imaging technique for the study of many anatomical districts in different clinical situations, as it provides a fast, reliable, and accurate simultaneous evaluation of different organs, including parenchyma, hollow viscera, vessels, and bony structures. It has also equipped the radiologist with the ability to explore areas that in the last decade were largely ignored by CT, especially the coronary arteries and the colon, and to limit invasive diagnostic tests (e.g., catheter angiography) to those cases in which interventional procedures are required. The examination quality and the consequent diagnostic accuracy of MDCT are the results of an optimized study technique, which nonetheless needs to be adapted to the particular clinical situation of the patient, while bearing in mind the radiation exposure. Another fundamental parameter in the optimization of MDCT is the protocol for the intravenous injection of iodinated contrast material; in these studies, multiple variables, some modifiable by the operator and others patient-dependent, must be considered based on the aims of maximizing arterial and venous enhancements whilst minimizing the dose of iodine injected, saving money, and increasing patient safety. Through the presentation of cases addressing different anatomical regions and various clinical indications, including emergency and neuro-imaging, this volume seeks to provide the general radiologist and trainee specialist with a guide to the main study protocols to be implemented in order to optimize examination quality and, consequently, facilitate the diagnostic process.

Abstrak :
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.