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Abstrak :
Perkembangan teknologi memainkan peranan penting dalam ketersediaan parameter pencitraan pada prosedur kateterisasi jantung, yang berdampak pada perlunya dilakukan optimasi pada kualitas citra dan tingkat dosis radiasi guna menentukan kombinasi parameter optimasi yang optimal. Pada kasus pasien anak (pediatrik), keperluan optimasi menjadi sangat penting sebab waktu hidup pasien yang lebih panjang dan sel yang lebih rentan terhadap radiasi. Tujuan dari penelitian ini adalah menentukan parameter pencitraan yang optimal di antara variasi yang diberikan, yakni mode pencitraan, diameter pembuluh darah (8, 6, 4, 2, dan 1 mm), dan konsentrasi media kontras berbasis Iodin (16%, 14%, 12%, dan 10% pada larutan plasma darah), dengan Figure of Merit (FOM) sebagai parameter. Fantom dibuat sebagai pengganti pasien pediatrik. Pengukuran Entrance Surface Air Kerma (ESAK) dan dosis keluaran dilakukan bersamaan dengan kalkulasi Signal-to-Noise Ratio (SNR) dari masing-masing variasi. Dari kalkulasi dosis dan kualitas citra, FOM untuk semua variasi dapat dikalkulasi dan kondisi optimum dapat ditentukan. Sebagai hasil, mode low dose pada fluoroskopi dan mode 15 fps low contrast mode ditentukan sebagai mode paling optimum untuk pasien berketebalan 10 cm. Ditemukan pula bahwa material timah tidak cocok digunakan dalam studi karena nilai SNR yang terlalu jauh jika dibandingkan dengan larutan Iodin. ...... Technological development plays an essential role in expanding the breadth of imaging parameters in cardiac catheterization procedure, consequencing on the need of optimization involving image quality and dose level to consider the most favorable parameter combination. In the case of paediatric patients, the awareness is greater owing to the longer life expectancy as well as higher vulnerability against radiation effects in younger cells. The purpose of this study is to assess the most favorable imaging parameters among varied factors, i.e. the available imaging modes, vessel diameter (8, 6, 4, 2, and 1 mm), and iodine-based contrast agent’s concentration (16%, 14%, 12%, and 10% in a blood plasma solution), employing Figure of Merit (FOM) as optimization parameter. In house phantom was constructed to accommodate all variations within the dimensional constrain of a paediatric patient. Measurements of Entrance Surface Air Kerma (ESAK) and exit dose were performed along with calculations of Signal-to-Noise Ratio (SNR) of each varied objects. From the measured dose and image quality, calculation of FOM was done resulting that of all modes, it was favorable to employ low dose fluoroscopy mode and lower frame/s mode in cine acquisition due to low delivered dose and insignificant image quality change among the modes. Higher frame/s cine modes were, however, usable when clinical situation dictates with the expense of the dose level being twice as much as the lower frame rate cine modes. This work also found that the use of Tin as Iodine replacement for research purposes is inadvisable.

Abstrak :
[Studi ini telah dilakukan untuk mengetahui karakteristik dari EPID dosimetri yang digunakan sebagai verifikasi pasien IMRT dan VMAT. Penelitian ini dilakukan dengan membandingkan indeks gamma dari hasil verifikasi 5 pasien brain, 5 pasien cervix, 5 pasien kepala dan leher serta 5 pasien paru menggunakan EPID dosimetri dengan MatriXX 2D array pada dua Linac yang berbeda di instalasi radioterapi MRCCC SHS dan Siloam Hospital TBS. Dari penelitian ini dihasilkan nilai indeks gamma untuk kasus IMRT di MRCCC 99.59% ± 0.46 untuk EPID dosimetri dan 99.13% ± 0.75 untuk MatriXX 2D array, sedangkan di Siloam Hospital TBS 99.8% ± 0.20 untuk EPID dosimetri dan 99.71% ± 0.14 untuk MatriXX 2D array. Pada kasus VMAT di MRCCC 97.71% ± 1.27 untuk EPID dosimetri dan 99.50% ± 0.39 untuk MatriXX 2D array, sedangkan di Siloam Hospital TBS 97.78% ± 1.45 untuk EPID dosimetri dan 98.66% ± 1.26 untuk MatriXX 2D array. Kesimpulan dari penelitian ini adalah perbedaan antara EPID dosimetri dan MatriXX 2D array di kedua rumah sakit menunjukan nilai kurang dari 1% untuk kasus IMRT dan kurang dari 2% untuk kasus VMAT. ......This work was aimed to study the characteristics of EPID dosimetry in use as patient specific QA for IMRT and VMAT. We compare result of gamma index from patient specific QA with each 5 cases of brain, cervix, head and neck, lung using EPID dosimetry and MatriXX 2D array in two different linacs at MRCCC SHS and Siloam Hospital TBS. Calculated gamma index from IMRT case in MRCCC SHS ware 99.59% ± 0.46 for EPID dosimetry and 99.13% ± 0.75 for MatriXX 2D array, meanwhile at Siloam Hospital TBS the calculated gamma index were 99.8% ± 0.20 for EPID dosimetry and 99.71% ± 0.14 for MatriXX 2D array.Gamma index from VMAT cases in MRCCC were 97.71% ± 1.27 for EPID dosimetry and 99.50% ± 0.39 for MatriXX 2D array, and in Siloam Hospital TBS the value were 97.78% ± 1.45 for EPID dosimetry and 98.66% ± 1.26 for MatriXX 2D array. We conclude that the difference between EPID dosimetry and Matrixx 2D arrays at two hospitals were less than 1% and less than 2% for IMRT and VMAT cases, respectively. This work was aimed to study the characteristics of EPID dosimetry in use as patient specific QA for IMRT and VMAT. We compare result of gamma index from patient specific QA with each 5 cases of brain, cervix, head and neck, lung using EPID dosimetry and MatriXX 2D array in two different linacs at MRCCC SHS and Siloam Hospital TBS. Calculated gamma index from IMRT case in MRCCC SHS ware 99.59% ± 0.46 for EPID dosimetry and 99.13% ± 0.75 for MatriXX 2D array, meanwhile at Siloam Hospital TBS the calculated gamma index were 99.8% ± 0.20 for EPID dosimetry and 99.71% ± 0.14 for MatriXX 2D array.Gamma index from VMAT cases in MRCCC were 97.71% ± 1.27 for EPID dosimetry and 99.50% ± 0.39 for MatriXX 2D array, and in Siloam Hospital TBS the value were 97.78% ± 1.45 for EPID dosimetry and 98.66% ± 1.26 for MatriXX 2D array. We conclude that the difference between EPID dosimetry and Matrixx 2D arrays at two hospitals were less than 1% and less than 2% for IMRT and VMAT cases, respectively.;This work was aimed to study the characteristics of EPID dosimetry in use as patient specific QA for IMRT and VMAT. We compare result of gamma index from patient specific QA with each 5 cases of brain, cervix, head and neck, lung using EPID dosimetry and MatriXX 2D array in two different linacs at MRCCC SHS and Siloam Hospital TBS. Calculated gamma index from IMRT case in MRCCC SHS ware 99.59% ± 0.46 for EPID dosimetry and 99.13% ± 0.75 for MatriXX 2D array, meanwhile at Siloam Hospital TBS the calculated gamma index were 99.8% ± 0.20 for EPID dosimetry and 99.71% ± 0.14 for MatriXX 2D array.Gamma index from VMAT cases in MRCCC were 97.71% ± 1.27 for EPID dosimetry and 99.50% ± 0.39 for MatriXX 2D array, and in Siloam Hospital TBS the value were 97.78% ± 1.45 for EPID dosimetry and 98.66% ± 1.26 forMatriXX 2D array. We conclude that the difference between EPID dosimetry and Matrixx 2D arrays at two hospitals were less than 1% and less than 2% for IMRT and VMAT cases, respectively., This work was aimed to study the characteristics of EPID dosimetry in use as patient specific QA for IMRT and VMAT. We compare result of gamma index from patient specific QA with each 5 cases of brain, cervix, head and neck, lung using EPID dosimetry and MatriXX 2D array in two different linacs at MRCCC SHS and Siloam Hospital TBS. Calculated gamma index from IMRT case in MRCCC SHS ware 99.59% ± 0.46 for EPID dosimetry and 99.13% ± 0.75 for MatriXX 2D array, meanwhile at Siloam Hospital TBS the calculated gamma index were 99.8% ± 0.20 for EPID dosimetry and 99.71% ± 0.14 for MatriXX 2D array.Gamma index from VMAT cases in MRCCC were 97.71% ± 1.27 for EPID dosimetry and 99.50% ± 0.39 for MatriXX 2D array, and in Siloam Hospital TBS the value were 97.78% ± 1.45 for EPID dosimetry and 98.66% ± 1.26 forMatriXX 2D array. We conclude that the difference between EPID dosimetry and Matrixx 2D arrays at two hospitals were less than 1% and less than 2% for IMRT and VMAT cases, respectively.]

Abstrak :
Telah dilakukan penelitian untuk mengetahui kemurnian dan kuat kerma udara Sk sumber butiran 125I buatan BATAN melalui pengukuran dan parameter dosimetrinya menggunakan simulasi Monte Carlo EGSnrc. Parameter dosimetri seperti kuat kerma udara Sk, tetapan laju dosis , faktor geometri G(r,), fungsi dosis radial g (r) dan fungsi anisotropi F(r,) dikalkulasi berdasarkan protokol AAPM TG 43. Hasil pengukuran dengan spektrometer gamma diperoleh sumber butiran 125I murni dan tidak mengandung radioisotop lain. Sedangkan hasil pengukuran kuat kerma udara menggunakan detektor ekstrapolasi untuk sumber 125I S1 dan S2 adalah 7,65 U dan 8,03 U dan hasil kalkulasi kuat kerma udara sumber 125I S1 dan S2 adalah 7,99 U dan 8,44 U. Terdapat perbedaan kurang dari 5 % antara pengukuran dan kalkulasi. Dari kalkulasi diperoleh fungsi dosis radial dengan persamaan polynomial y = - 0,0002 x5 + 0,0044 x4 ? 0,0475 x3 + 0,2413 x2 - 0,6960 x + 1,5214 dengan R = 0,99. Fungsi dosis radial dan fungsi anisotropi dari sumber butiran 125I buatan BATAN hasil simulasi Monte Carlo EGSnrc ini mempunyai bentuk kurva yang tidak berbeda dengan sumber 125I komersial model IAI-125 buatan IsoAid. Detektor ekstrapolasi milik SSDL BATAN dapat digunakan untuk menentukan kuat kerma udara sumber butiran 125I. ......This study was performed to know the purity and kerma strength of the BATAN seed 125I brachytherapy sources obtained by experiment using an extrapolation chamber and dosimetric parameters of them using a EGSnrc Monte Carlo simulation. Dosimetric parameters such as air kerma strength Sk, dose rate constant , geometry factor G(r,), radial dose function g(r) and anisotropy function F(r,) were calculated based on the AAPM TG 43 protocol. From the measurement result was obtained that the BATAN seed 125I brachytherapy sources did not contain other radioisotope. The kerma strength of S1 and S2 sources from experiment were 7.65 U and 8.03 and from the calculation were 7.99 U and 8.44 U. The difference between experiment and calculation was less than 5 %. Radial dose function from the calculation has polynomial equation y = with R = 0,99. EGSnrc Monte Carlo simulation for radial dose function and anisotrophy function of the BATAN had the same curve with the calculation of the IsoAid 125I source model IAI-125 commercially. Extrapolation chamber belonged to the SSDL BATAN can be used to determine kerma strength.

Abstrak :
ABSTRAK
Tujuan penelitian ini mengevaluasi perencanaan terapi radiasi kasus nasofaring dengan teknik Intensity Modulated Radiation Therapy IMRT dan Volumetric Modulated Arc Therapy VMAT menggunakan algoritma Analytical Anisotropic Algorithm AAA dan Acuros External Beam AXB versi 13.0.01. Penelitian dibagi menjadi tiga yaitu 1 analisa dose volume histogram DVH di TPS, 2 verifikasi dosis fantom slab memakai film Gafchromic EBT3 dan bilik ionisasi CC13, dan 3 verifikasi fantom rando memakai film Gafchromic EBT3 dan Thermoluniscence Dosimeter TLD . Analisa DVH menghasilkan penyimpangan AXBDm dan AXBDw terhadap AAA pada PTVtulang sebesar -1.5 dan 2.0 , sedangkan pada organ sehat inner ear dan mandibula penyimpangan AXBDm dan AXBDw sebesar 8 . Conformity index AXBDm untuk IMRT dan VMAT adalah 0.58 dan 0.61, sedangkan homogeneity index AAA adalah 0.06 dan 0.05. Deviasi pengukuran dengan slab homogen dan inhomogen menunjukkan Acuros lebih kecil bacaan deviasinya dibandingkan AAA, dengan nilai deviasi 0.10 - 7.78 . Verifikasi dosis titik dengan fantom rando menunjukkan hasil yang acak, nilai deviasi menunjukkan pola yang tidak bisa diprediksi terhadap algoritma mana yang akan menghasilkan deviasi lebih kecil. Pengukuran nilai gamma dengan kriteria 7 /4mm dihasilkan passing rate gamma index untuk IMRT pada AAA, AXBDm, dan AXBDw sebesar 52.7 , 90.7 , dan 63.66 , sedangkan VMAT sebesar 61.51 , 90.09, dan 92.67 .

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ABSTRACT
The purpose of this study to evaluate the radiation therapy planning techniques nasopharyngeal case with Intensity Modulated Radiation Therapy IMRT and Volumetric Modulated Arc Therapy VMAT using algorithm Anisotropic Analytical Algorithm AAA and Acuros External Beam AXB version 13.0.01. The study was divided into three 1 the analysis of dose volume histogram DVH at TPS, 2 verification dose in slab phantom using film Gafchromic EBT3 and ionization chamber CC13, and 3 verification dose in rando phantom use film Gafchromic EBT3 and Thermoluminiscence Dosimeter TLD . DVH analysis resulted in deviations AXBDm and AXBDw to AAA on PTVbone amount 1.5 and 2.0 , whereas in healthy organs mandibula and inner ear and deviation of AXBDm to AXBDw up to 8 . Conformity index AXBDm for IMRT and VMAT is 0.58 and 0.61, while AAA homogeneity index is 0.06 and 0.05. Deviation measurements with homogeneous slab and inhomogen Acuros readings indicate the deviation compared to AAA, with a deviation 0 10 7.78 . . Point dose verification with fantom rando shows random results. Gamma value measurement criteria of 7 4mm generated gamma passing rate index for IMRT for AAA, AXBDm, and AXBDw was.7 , 90.7 and 63.66 , while VMAT was 61.51 , 90.09, and 92.67 .