Hepatik Arter Embolizasyonları Sırasında C Kollu Bilgisayarlı Tomografi Yöntemi ile Elde Edilen Kontrastlı- Dual Faz Görüntülerin Tümör Saptanabilirliği ve Tedavi Öngörülebilirliği Açısından Embolizasyon Öncesi ve Sonrasında Rutin Yapılan Kesitsel Görüntülemeler ile Karşılaştırılması

Abstract

Comparison of contrast enhanced dual phase images acquired with C arm Computed Tomography during hepatic arterial embolizations with routinely performed cross-sectional imaging techniques before and after embolization in terms of tumor detectability and treatment response prediction, Hacettepe University Faculty of Medicine, Thesis in Radiology, Ankara,2014. The aims of this study are, (1) to demonstrate that dual phase imaging (early arterial and late arterial phase) is doable with C-arm computed tomography (C-arm CT) during hepatic arteriographies in radiembolization (RE) procedures, (2) to compare these two phases in terms of lesion detectability, and (3) to compare these images with cross-sectional imaging techniques routinely performed pre and postembolization regarding the embolization effects and potential benefits of these changes like prediction of treatment response. Nineteen patients who were diagnosed with hepatocellular carcinoma (HCC) and who were enrolled for RE treatment are included in this prospective study. During RE procedure dual phase (acquiring early and late phase images with breathhold at different times after arterial injection of contrast) C-arm CT were performed before and after microsphere infusions. Postprocessed images (done by using a prototype software) were evaluated by two interventional radiologists. 1. Dual phase C-arm CT imaging is doable and can be easily repeated. 2. There was no statisticall difference between two phases in lesion detectability (p=1). 3. During procedures C-arm CT showed that tumor load in all patients have progressed in the time between preembolisation cross-sectional images and angiography dates. 4. Comparison of two phases regarding tumor enhancement showed that dense contrast media in hepatic artery lumen at early arterial phase and prominent tumor enhancement at late arterial phase. Luminal contrast in early arterial phase enables mapping for selective catheterization whereas it also causes artifacts decreasing the image quality. Two radiologist scaled each phase for image quality . Total score of early phase was 57, late phase was 61 (max value 76; 19 patients x 2 observers x 2 points). 5. No statisticall differance was found between two phases regarding the embolization effect (change of tumoral contrast enhancement pre and post embolisation). Quantitative HU values were obtained in all patients who had a decrease in tumoral contrast enhancement visually (mean decrease in HU density; arterial phase 75,3±23 HU , delayed phase 63.1±24 HU) 6. The study and patient follow-up is going on in order to see whether changes obtained after embolisation provides treatment response prediction. Up to now, in all patients having a decreased HU value in postembolization images, showed a partial response and a decrease in tumour enhancement at third month follow up cross-sectional imagings. As a result, dual phase C-arm CT during hepatic arteriographies in RE treatment is a doable and reliable technique in lesion detectability and a promising tool to guide future angiographic treatments.