Hipokampus Koruyucu Tüm Beyin Radyoterapisinde Koplanar ve Non-Koplanar VMAT Planlarının Karşılaştırılması

Öz

Bu çalışmada, hipokampus koruyucu tüm beyin radyoterapisinde volümetrik modüle ark tedavisi tekniği kullanılarak oluşturulan koplanar ve non-koplanar tedavi planlarının hipokampusun korunması ve diğer kritik organ dozları üzerindeki etkileri araştırılmıştır. Çalışmada, beyin metastazı tanısı olan 18 hastaya ait hipokampus korumalı tüm beyin radyoterapisi planları koplanar ve non-koplanar olarak karşılaştırılmıştır. Tüm planlamalar Monaco tedavi planlama sistemi kullanılarak oluşturulmuş ve analiz edilmiştir. Hipokampus bölgesi Radyasyon Tedavisi Onkoloji Grubu kılavuzlarına uygun şekilde konturlanmış, hedef hacim kapsamı, doz homojenliği ve kritik organ dozları değerlendirilmiştir. Hedef ve kritik organ dozları açısından hedef hacmin yüzde doksan beşini kapsayan doz ve hedef hacim–hipokampus doz değerleri bakımından planlar arasında istatistiksel olarak anlamlı fark saptanmamıştır. Bununla birlikte, hedef hacimdeki yüksek doz bölgelerini temsil eden parametre açısından non-koplanar planlar lehine istatistiksel olarak anlamlı bir fark belirlenmiştir. Hipokampus koruyucu tüm beyin radyoterapisi, etkili intrakraniyal hastalık kontrolü sağlarken nörobilişsel fonksiyonların korunması açısından önemli bir denge sunmaktadır. Koplanar ve non-koplanar tekniklerin her biri belirli avantajlar sağlamakta olup tedavi planlaması hasta anatomisi ve klinik önceliklere göre bireyselleştirilmelidir.

Anahtar Kelimeler

• Koplanar
• hipokampal koruma
• non-koplanar
• radyoterapi
• tüm beyin radyoterapisi

Etik Beyan

Bu çalışma, Eskişehir Osmangazi Üniversitesi Girişimsel Olmayan Klinik Araştırmalar Etik Kurulu tarafından incelenmiş ve etik açıdan uygun bulunmuştur (Karar Tarihi: 17.05.2022, Karar No: 04). Araştırma retrospektif ve dozimetrik nitelikte olup klinik uygulamayı veya hasta tedavisini etkileyecek herhangi bir ek girişim içermemektedir. Çalışma kapsamında kullanılan tüm veriler anonimleştirilmiş, kişisel sağlık bilgilerinin gizliliği ilgili mevzuat ve etik kurallar çerçevesinde korunmuştur.

Comparison of Coplanar and NonCoplanar VMAT Plans in HippocampusSparing Whole-Brain Radiotherapy

Öz

This study aimed to evaluate the effects of coplanar and non-coplanar treatment plans generated using the volumetric modulated arc therapy technique on hippocampal sparing and doses delivered to other critical organs in whole-brain radiotherapy. Hippocampal-sparing whole-brain radiotherapy plans of eighteen patients diagnosed with brain metastases were retrospectively evaluated. All treatment plans were created and analyzed using the Monaco treatment planning system. The hippocampus was contoured in accordance with the Radiation Therapy Oncology Group guidelines, and plans were assessed in terms of target volume coverage, dose homogeneity, and doses to critical organs. No statistically significant difference was observed between coplanar and non-coplanar plans regarding target volume coverage and target volume–hippocampus dose parameters. However, non-coplanar plans demonstrated significantly better control of high-dose regions within the target volume. Hippocampal-sparing whole-brain radiotherapy represents an important approach that balances effective intracranial disease control with preservation of neurocognitive function. Both coplanar and non-coplanar techniques offer specific dosimetric advantages, and treatment planning should be individualized according to patient anatomy and clinical priorities.

Anahtar Kelimeler

• Coplanar
• hippocampal sparing
• non-coplanar
• radiotherapy
• whole-brain radiotherapy

Etik Beyan

This study was reviewed and approved by the Eskişehir Osmangazi University Non-Interventional Clinical Research Ethics Committee (Decision Date: May 17, 2022; Decision No: 04). The study was designed as a retrospective dosimetric analysis and did not include any additional intervention affecting patient treatment. All data were anonymized prior to analysis, and patient confidentiality was maintained in accordance with ethical standards and relevant regulations.

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