Tüm Beyin Radyoterapisinde YART Tekniği ile Hipokampus Korumalı Planların Dozimetrik Karşılaştırılması

Yıl 2021, Cilt: 31 Sayı: 1, 76 - 81, 31.01.2021

Hamit Başaran Gökçen İnan Osman Vefa Gül Mürsel Düzova Abdüssamet Hamit Batur

Öz

Amaç: Bu çalışmada tüm beyin radyoterapi tedavisinde hipokampus korumalı dinamik yoğunluk ayarlı radyoterapi D-YART ve statik yoğunluk ayarlı radyoterapi S-YART tekniklerinin dozimetrik karşılaştırılması amaçlanmıştır.Gereç ve Yöntem: Bölümümüzde 2019-2020 yılları arasında tüm beyin kanseri nedeniyle radyoterapi uygulanan 10 hasta çalışmaya dahil edilmişitir. Her hasta için hipokampus korumalı tüm beyine yönelik iki farklı yoğunluk ayarlı radyoterapi YART planları hazırlanmıştır. Planlanan hedef hacim PTV , hipokampus, beyin sapı, optik kiazma, göz, lens gibi risk altındaki organlar RAO , doz homojenite indeksi DHI , conformite indeksi CI , monitör ünitler MU açısından D-YART planları S-YART planları ile karşılaştırılmıştır.Bulgular: Yapılan istatistiksel karşılaştırma sonucunda PTV’ye ait değerlerin analizinde D-YART ve S-YART arasında CI değerinde anlamlı fark görülmüştür p=0.000 . Hipokamus korumalı YART planlarında S-YART tekniğinde beyin sapı, optik kiazma,ve optik sinir gibi kritik organların aldığı ortalama dozlar D-YART tekniğine göre anlamlı derecede azaldığı görülmüştür sırasıyla p=0.000, p=0.003, p=0001 ve p=0.000 . Lens dozları analiz edildiğinde, sağ ve sol lenslerin ortalama doz değerlerinin S-YART tekniğinde daha düşük olduğu gözlenmiştir. p=0.000 .Sonuç: Tüm beyin radyoterapisi nedeniyle hipokampus korumasına yönelik D-YART tekniği ile S-YART teknikleri karşılaştırıldığında, S-YART tekniğinin hipokampus ve diğer kritik organları daha iyi koruduğu görülmüştür

Anahtar Kelimeler

Dinamik yoğunluk ayarlı radyoterapi, hipokampus, statik yoğunluk ayarlı radyoterapi

Dosimetric comparison of imrt plans in whole brain hippocampal sparing radiotherapy

Öz

Objective: The aim of this study was to compare dosimetric advantages of using dynamic intensity-modulated radiation therapy D-IMRT and static intensity-modulated radiation therapy S-IMRT techniques for whole-brain radiation therapy WBRT with hippocampus sparing HS . Material and Methods: 10 patients with whole brain radiorherapy were retrospectively selected between the years of 2019-2020. For wholebrain radiation therapy WBRT with hippocampus sparing HS , two treatment plans were created and compared with respect to the doses received by planning target volume PTV and the organ at risk OARs including hipokampus, brain system, optic chiasma, eyes, lens, the dose homogeneity index DHI , conformity indexes CI and total monitor unit counts MU required for the treatment. Results : As a result of the statistical comparison, a significant difference was observed in the CI value between D-YART and S-YART p = 0.000 . The mean doses of critical organs such as the brainstem, optic chiasma, and optic nerve were significantly reduced in the S-YART plans compared to the D-YART plans p = 0.000, p = 0.003, p = 0001 and p = 0.000, respectively . When the lens doses were analyzed, it was observed that the mean dose values of the right and left lenses were lower in the S-YART technique p = 0.000 . Conclusions: For whole-brain radiation therapy WBRT with hippocampus sparing HS , S-IMRT provided better protection for hippocampus and OARs compared to D-IMRT

Anahtar Kelimeler

Dynamic intensity-modulated radiation therapy, hippocampus, static intensity-modulated radiation therapy

Kaynakça

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