Determination of the effective radiation dose of the patient in computed tomography

Öz

In recent years, the use of computed tomography (CT) has been recognized by all authorities as an indispensable imaging technology for diagnosing patients. With the introduction of multislice CT devices that were very fast, the patients could be examined without the need for anesthesia. This has led to an excessive increase in the use of CT in pediatric patients. In adults, a large part of the excessive increase is observed in asymptomatic patients such as CT colonoscopy, cardiac angiography and whole body scan. The excessive use of CT increases the risk of exposure to radiation. In this study, in order to reveal the actual radiation dose that the patient was exposed to in the CT examinations, a comparison was made between the value obtained from the CT device and the radiation dose exposed to by the patient. Thermoluminescence (TLD) detectors were placed on 25 patients. It was found that there was a 4% difference between the radiation dose read from the CT and the radiation dose from the TLD crystals.

Anahtar Kelimeler

• Computed Tomography,TLD,X-ray,ASIR

Bilgisayarlı tomografilerde hastanın aldığı efektif radyasyon dozunun belirlenmesi

Öz

Son yıllarda bilgisayarlı tomografi (BT) kullanımı hastalara tanı koyabilme açısından vazgeçilmez bir görüntüleme teknolojisi olduğu tüm otoritelerce kabul edilmekle birlikte BT kullanımının aşırıya kaçtığı da kabul edilmektedir. Çok hızlı olan çok kesitli BT cihazlarının kullanıma girmesi ile çocuk hastalarda anestezi uygulamasına gerek kalmadan tetkikleri yapılabilmiştir. Bu durum da çocuk hastalarda BT kullanımında aşırı artışa sebep olmuştur. Yetişkinlerde ise aşırı artışın büyük bir bölümünü asemptomatik hastalarda BT kolonoskopi, kardiyak anjiyo ve tüm vücut tarama gibi tetkikler oluşturmaktadır. BT kullanımının bu kadar aşırı olması da beraberinde radyasyona maruz kalma riskini artırmaktadır. Bu çalışmada, BT tetkiklerinde hastanın maruz kaldığı gerçek radyasyon dozunun ortaya konması amacıyla BT cihazından okunan değer ile gerçekte hastanın aldığı radyasyon dozunun karşılaştırılması yapılmıştır. Bunun için 25 hasta üzerine termolüminesans (TLD) detektörleri yerleştirilmiştir. BT cihazından okunan radyasyon dozu ile TLD kristallerinden okunan radyasyon dozu arasında %4 farklılık olduğu bulunmuştur. 

Anahtar Kelimeler

• Bilgisayarlı tomografi,TLD,X ışınları,ASIR

Kaynakça

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