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Abstrak :
Penelitian ini bertujuan untuk mempelajari karakteristik dosimetri dari film gafchromic XR-RV3 yang memiliki sensitifitas terhadap rentang dosis 1 cGy hingga 30 Gy serta membandingkannya dengan film EBT2 dengan rentang dosis 1 cGy hingga 40 Gy untuk verifikasi dosis pada Radioterapi. Karakteristik film seperti respon terhadap dosis tinggi, pengaruh energi serta orientasi film menjadi fokus penelitian. Pengukuran dilakukan menggunakan energi Megavoltage x-rays (6 MV dan 10 MV), dan Cobalt 60 yang sudah dikalibrasi sesuai dengan protokol dosimetri IAEA TRS-398. Respon film pada masing-masing energi diukur pada rentang dosis 50 cGy hingga 10 Gy. Pemindaian pada masing-masing film menggunakan EPSON Perfection V700 flatbed scanner, mode transmisi untuk film EBT2 dan mode refleksi untuk film XR-RV3, 48 bit color, dan resolusi spasial 75 dpi. Data yang diperoleh dianalisa menggunakan software FilmQA Pro, ROI berukuran 3 x 3 cm2 pada bagian tengah dari film untuk memperoleh nilai pixel rata-rata. Untuk masing-masing nilai pixel yang diperoleh dari masing-masing film selanjutnya ditentukan nilai rata-rata net Optical Density (netOD). Respon bacaan film EBT2 dan XR-RV3 pada rentang energi yang berbeda menunjukkan pengaruh energi yang rendah dengan deviasi rata – rata sebesar ±1%. Hasil perbandingan karakteristik respon bacaan film EBT2 dan XR-RV3 untuk masing-masing modalitas energi berbeda menunjukkan deviasi sebesar ±3%. Pengujian respon bacaan film XR-RV3 pada sisi orientasi yang berbeda tidak menunjukkan perbedaan yang signifikan dengan deviasi rata – rata sebesar 0.2%. Hasil evaluasi profil berkas menggunakan film XR-RV3 menunjukkan jumlah noise (disturbance) yang lebih banyak dibandingkan dengan EBT2. Pengukuran nilai simetris dan kerataan berkas pada rentang energi Cobalt-60 menunjukkan penyimpangan yang cukup besar pada posisi film horizontal terhadap sumbu utama berkas yaitu diatas 30%. Pengujian sensitifitas respon bacaan film XR-RV3 pada dosis tinggi dan dosis rendah menunjukkan hasil yang lebih baik dibandingkan dengan film EBT2. ...... The purpose of this study is to compare the dosimetry characterization of XR-RV3 film with its sensitivity to dose levels from 1 cGy to 30 Gy and EBT2 film with its sensitivity to dose levels from 1 cGy to 40 Gy for dose verification in radiation therapy. The characteristics of film such as response at high dose levels, energy dependence and side orientation dependence to scanner were the main focus of this study. The film response to each energy (foton 6 MV, 10 MV and Cobalt-60) was measured over the dose levels from 50 cGy to 10 Gy and the output source were calibrated following IAEA TRS-398 Dosimetry Protocol. Each film piece was scanned using EPSON Perfection V700 flatbed scanner, 48-bit color, 75 dpi spatial resolution, Transmission mode for EBT2 film and Reflection mode for XR-RV3 film. The data were analyzed using FilmQA Pro Software and for each scanned image, a ROI size 3 x 3 cm2 at the field center was selected to obtain the mean pixel value. Furthermore, the pixel value from each film were calculated to find the average of net Optical Density (netOD). From this study, the result revealed that there was no significant difference in characteristics response between XR-RV3 and EBT2 film with standar deviation of ±3%. The energy dependence of XR-RV3 and EBT2 film was found to be relatively small within measurement uncertainties ±1%. The dependence of XR-RV3 film side orientation is negligibly small with the standard deviation of 0.2%. The result of beam profile dosimetry evaluation using XR-RV3 showed more amount of noise or disturbance than EBT2 film. The measurement of beam symmetry and beam flatness on energy range of Cobalt-60, showed a significant error of film in horizontal position at central axis beam that was above 30%. In addition, the sensitivity of response XR-RV3 film at high and low dose shown better result than EBT2 film.

Abstrak :
[ABSTRAK
Telah dilakukan verifikasi dosis organ target dan jaringan sehat di sekitar target dengan menempatkan TLD Rod LiF100 dan film Gafchromic EBT2 di lubang slab bagian pelvis dari phantom Rando Alderson untuk simulasi kanker prostat. TLD dievaluasi menggunakan TLD Reader Harshaw, sementara Film Gafchromic EBT2 dipindai menggunakan scanner Epson Perfection V700 dengan mode transmisi, red channel dan resolusi 72 dpi. Pengukuran dosis titik dilakukan dengan membandingkan antara dosis yang direncanakan TPS Eclipse ver. 11 dan dosis yang diukur pada target organ target dan organ beresiko menggunakan teknik IMRT dan VMAT. Hasilnya adalah deviasi dosis pada organ target menggunakan teknik IMRT dan VMAT adalah kurang dari 5%. Demikian pula, deviasi dosis pada bladder dan rectum untuk kedua teknik juga kurang dari 5% karena posisinya sangat dekat dengan target volume. Di sisi lain, deviasi dosis di femoral head lebih dari 5% untuk kedua teknik karena lokasinya pada gradien dosis rendah. Selanjutnya, deviasi dosis organ target untuk teknik IMRT cenderung lebih kecil dari teknik VMAT baik untuk TLD dan Film. Perbedaan dosis pada dosis titik organ target antara IMRT dan VMAT kurang dari 1% tetapi terjadi pada dosis yang random untuk organ beresiko. Adapun dosis permukaan pada teknik IMRT cenderung lebih kecil dari teknik VMAT jika kita menggunakan TLD, tetapi dosis pada film EBT2 cenderung sama antara teknik IMRT dan VMAT.

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ABSTRACT
Have been done the dose verification of the target and healthy tissues around by placing the TLD Rod LiF100 and EBT2 Gafchromic film at slab hole of pelvic part of the Alderson Rando phantom for prostate cancer simulation. The Exposed TLDs was evaluated using the TLD Reader Harshaw, while Gafchromic Film EBT2 was scanned using Epson Perfection V700 scanner with transmission mode, red channel and resolution 72 dpi. The point dose measurements were compared between planned dose TPS Eclipse ver. 11 and measured dose at target volume organ and organ at risk for IMRT and VMAT techniques. The result is the dose difference at target volume for IMRT and VMAT are less than 5%. Similarly, the dose difference at Bladder and Rectum for both techniques are also less than 5% due to the position of OAR is very close to target volume. On the other hand, the dose difference at Femoral head are more than 5% for both techniques because the location of OAR already in low gradient dose. Furthermore, the difference dose of the target volume for IMRT technique is tends to be smaller than VMAT either for TLD and film detectors. The dose difference at point dose of target volume between IMRT and VMAT techniqe are less than 1% but it occur in random number for organ at risk. More over, the surface dose of IMRT tend to be smaller than VMAT dose if we are using TLDs, but the dose of EBT2 films tend to be similar between IMRT and VMAT techniques, Have been done the dose verification of the target and healthy tissues around by placing the TLD Rod LiF100 and EBT2 Gafchromic film at slab hole of pelvic part of the Alderson Rando phantom for prostate cancer simulation. The Exposed TLDs was evaluated using the TLD Reader Harshaw, while Gafchromic Film EBT2 was scanned using Epson Perfection V700 scanner with transmission mode, red channel and resolution 72 dpi. The point dose measurements were compared between planned dose TPS Eclipse ver. 11 and measured dose at target volume organ and organ at risk for IMRT and VMAT techniques. The result is the dose difference at target volume for IMRT and VMAT are less than 5%. Similarly, the dose difference at Bladder and Rectum for both techniques are also less than 5% due to the position of OAR is very close to target volume. On the other hand, the dose difference at Femoral head are more than 5% for both techniques because the location of OAR already in low gradient dose. Furthermore, the difference dose of the target volume for IMRT technique is tends to be smaller than VMAT either for TLD and film detectors. The dose difference at point dose of target volume between IMRT and VMAT techniqe are less than 1% but it occur in random number for organ at risk. More over, the surface dose of IMRT tend to be smaller than VMAT dose if we are using TLDs, but the dose of EBT2 films tend to be similar between IMRT and VMAT techniques]

Abstrak :
Verifikasi dosis TPS (Treatment Planning System) mutlak diperlukan sebagai suatu pelaksanaan progam jaminan kualitas Radioterapi. Sebagian besar jaminan kualitas dosis dilakukan didalam area radiasi, sedangkan pemantauan dosis organ kritis berada diluar area radiasi. Berdasarkan hal tersebut dilakukan verifikasi TPS untuk dosis organ kritis (ginjal, caput femur, ovarium, dan vagina) menggunakan linac dan TPS milik RSPP. Simulasi pengukuran dosis dilakukan dengan memberikan perlakuan radioterapi area pelvis box field pada rando phantom (SAD 100 cm, foton 10 MV) serta menggunakan TLD sebagai dosimeter. Dosis simulasi akan dijadikan acuan untuk memverifikasi dosis TPS. Berdasarkan verifikasi tersebut diperoleh hasil bahwa kalkulasi dosis TPS sesuai untuk organ kritis caput femur, ovarium, dan vagina, dengan persen error kurang dari 5%. Sedangkan untuk organ kritis ginjal, kalkulasi TPS tidak sesuai dikarenakan persen error yang mencapai 17% untuk lapangan B dan 90% untuk lapangan A yang berukuran lebih kecil dari lapangan B. Dalam penelitian ini juga dilakukan pengambilan data penumbra untuk mengetahui batas kemampuan kalkulasi TPS yang dimiliki.

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Verification of TPS`s (Treatment Planning System) dose calculation is necessary as a program of quality assurance (QA) for radiotherapy. Most proccess of QA are infield, while evaluation for organ-at-risk (OAR) dose is outfield. Based on that, verification of TPS`s dose had been done for OAR (kidney, femoral head, ovary, and vagina) using linac and TPS at RSPP. Simulation for dose measurement was done by giving pelvic area radiotherapy (box field, SAD 100 cm, photon 10 MV) to rando phantom and using TLD as a dosimetry. Simulation`s dose would be used as the reference to verify TPS`s dose. Based on that, the result show that dose calculation of TPS was appropriate for femoral head, ovary, and vagina, that`s because percent error was less than 5%. Whereas for kidney, the calculation wasn`t appropriate because percent error reached 17% for field B and 90% for field A that has size smaller than field B. Penumbra`s data also had been taken in this research, to find out the limit of TPS`s calculation.