Abdullah TAYLAN, Banu KÜÇÜK TAYLAN, Özgür GÜNAL

PANDEMİ SIRASINDA ÖNEMİ ARTAN RADYOLOJİ TETKİKİ: DÜŞÜK- DOZ GÖĞÜS BT; COVID-19 OLGULARINDA STANDART- DOZ GÖĞÜS BT' YE KIYASLA TANISAL ETKİNLİK VE MARUZ KALINAN İYONLAŞTIRICI RADYASYON DOZU

Amaç: COVID-19 hastalarında düşük doz tekniğiyle elde olunan göğüs bilgisayarlı tomografisi (BT) taramalarının tanısal etkinliğini gözlemlemeyi, radyasyon dozlarını ve görüntüleme bulgularını rutin olarak kullanılan standart doz göğüs BT ile karşılaştırmayı amaçladık. Gereç ve Yöntem: Bu retrospektif çalışmaya, düşük ve standart doz olmak üzere iki farklı göğüs BT protokolü ile tetkik edilen 50 yaş altındaki 115 SARSCoV- 2 RT-PCR ile doğrulanmış olgu dahil edildi. BT bulguları ve efektif doz değerleri değerlendirildi ve iki teknik için karşılaştırıldı. Bulgular: Düşük doz BT protokolü ile tetkik edilen 65 olgunun 52'si (% 80) ve standart doz BT protokolü ile tetkik edilen 50 olgunun 44'ünde (% 88) COVID- 19 pnömonisi ile uyumlu radyolojik bulgular saptandı. Ortalama efektif doz değerleri, düşük doz BT protokolü için 0,60 ± 0,05 mSv, standart doz BT protokolü için 4,10 ± 1,81 mSv bulunmuş olup istatistiksel anlamlı farklılık saptandı. Periferik dağılım paterni gösteren, yuvarlak şekilli, çok odaklı buzlu cam opasiteleri ve/veya yamasal konsolidasyonlar, daha az sıklıkta görülen interlobüler septal kalınlaşma, Arnavut kaldırımı görünümü, ters- halo işareti olarak tanımlanan karakteristik COVID-19 akciğer lezyonlarının görülme sıklıklarında iki grup arasında anlamlı istatistiksel fark saptanmadı. Çoğu olguda her iki akciğer (% 69,7) tutulumu ve alt loblarda daha sık tutulum saptandı. 96 olgunun 27' sinde (% 28,1) yalnızca bir lob tutulumu saptandı. Sonuç: Göğüs BT, COVID-19 pnömonisinin teşhisi için birincil görüntüleme aracıdır. Özellikle genç nüfus için BT görüntülemenin önemli bir sınırlaması iyonlaştırıcı radyasyon maruziyetidir. Düşük doz göğüs BT, radyasyon maruziyetini önemli ölçüde azaltan uygun bir görüntüleme yöntemidir.

Radiology examination of increasing importance during the pandemic: Low-dose chest CT; diagnostic efficacy and exposure to ionizing radiation dose compared to standard-dose chest CT in COVID-19 cases

Objective: We aimed to observe the diagnostic efficacy of low-dose chest computed tomography (CT) scans in COVID-19 patients and to compare radiation doses and imaging findings with routinely used standard-dose chest CT. Materials and Methods: This retrospective study included 115 SARS-CoV-2 RT-PCR confirmed cases under 50 years of age who were examined with two different chest CT protocols, low and standard dose. CT findings and effective dose values were evaluated and compared for the two techniques. Results: Radiological findings were found to be consistent with COVID-19 pneumonia in 52 (80%) of 65 cases examined with low-dose CT protocol and in 44 (88%) of 50 cases examined with standard-dose CT protocol. Mean effective dose values were 0.60 ± 0.05 mSv for the low-dose CT protocol and 4.10 ± 1.81 mSv for the standard-dose CT protocol, and a statistically significant difference was found. No statistically significant difference was found between the two groups in the incidence of characteristic COVID-19 lung lesions, which showed a peripheral distribution pattern, defined as round-shaped, multifocal groundglass opacities and/or patchy consolidations, and less frequently interlobular septal thickening, crazy-paving pattern, and reverse-halo sign. In most cases, involvement of both lungs (69.7%) and more frequent involvement in the lower lobes were found. Only one lobe involvement was detected in 27 (28.1%) of 96 cases. Conclusion: Chest CT is the primary imaging tool for diagnosing COVID-19 pneumonia. An important limitation of CT imaging, particularly for the young population, is exposure to ionizing radiation. Low-dose chest CT is a feasible imaging technique that significantly reduces radiation exposure.

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