Vertebra Radyoterapisinde Cyberknife ve Imat Tekniklerinin İncelenmesi: Dozimetrik Çalışma

Çalışmamızda, TPS (Multiplan ve Eclipse tedavi planlama sistemlerinde) sanal olarak oluşturulan vertebra tümörünün doz dağılımları ile CIRS ATOM fantomda yapılan TLD ölçüm sonuçlarının karşılaştırılması amaçlanmıştır. Ölçümler için, CIRS ATOM fantomun 1 mm kalınlıkta BT görüntüleri alındı. Sağ böbrek, sol böbrek, spinal kord ve kalp organları kritik organ olarak ve hedef hacim olarak CTV tanımlandı. Eclipse (version 8.9.17) ve Multiplan (version 4.5.3) tedavi planlama bilgisayarlarında aynı kriterler kullanılarak planlamalar yapıldı. TLD pozisyonları TPS üzerinde belirlendi ve planlar üzerindeki değerler tespit edildi. Bu değerler TLD değerleriyle karşılaştırıldı. TLD ortalama okuma değeri ile Multiplan TPS de aynı noktadaki doz değeri karşılaştırıldığında minimum ve maksimum fark sırasıyla % 4.4 ve % 8.5 ti. Eclipse TPS de minimum ve maksimum fark sırasıyla % 4.4 ve % 46.5 bulundu. Sonuç olarak, her iki teknikte de kritik organ dozları açısından benzer sonuçlar elde edildi.

Anahtar Kelimeler:

Vertebral Işınlama, IMAT, SBRT, TPS Doğrulama, Dozimetri

Investigation of Cyberknife and Imat Techniques in Vertebra Radiotherapy: A Dosimetric Study

In our study, it was aimed to compare the dose distributions of the virtual formed vertebra tumor (L1 level) created in TPS (Multiplan and Eclipse treatment planning systems) with the results of TLD dosimetry in CIRS ATOM phantom. For measurements, Computed tomography (CT) images were performed for CIRS ATOM Rando phantom planning. Right kidney, left kidney, spinal cord and heart volumes were formed as critical organs and CTV was created as a target volume. Treatment plans were created using the same criteria in Eclipse (version 8.9.17) and Multiplan (version 4.5.3) TPS. TLD places were identified on the TPS and the values on the plane were read. These values were compared to TLD values. The minimum and maximum differences between the average read value at the TLD measurement point and the dose reading at the same point in the Multiplan TPS were 4.4% to 8.5%, respectively. The minimum and maximum differences between the average read value at the TLD measurement point and the dose reading at the same point in the Eclipse TPS were found as 4.4% and 46.1%, respectively. As conclusion, similar results were obtained in terms of critical organ doses in both techniques.

Keywords:

Vertebra Irradiation, IMAT, SBRT, TPS Accuracy, Dosimetry,

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