The possibility of using virtual unenhanced images created by using dual-energy CT data in the differential diagnostic of adrenal tumors: a retrospective study

INTRODUCTION: Dual-energy computed tomography (DECT) is a computed tomography method based on scanning a patient at low and high energies, one of the features of which is the ability to create virtual unenhanced images based on datasets obtained after contrast injection.

OBJECTIVE: Evaluation of the possibilities of using virtual unenhanced images created from arterial or venous phases by dualenergy computed tomography instead of native images in the differential diagnosis of adrenal gland tumors.

MATERIALS AND METHODS: 91 patients with adrenal gland tumors who subsequently underwent surgery due to the clinically malignant potential of the tumor or its hormonal activity were included in the study. All patients underwent contrast-enhanced computed tomography and dual-energy scanning in the arterial and venous phases. As part of the postprocessing, virtual unenhanced images from the arterial and venous phases were constructed. Next, the densities of tumors in the native image and virtual unenhanced images were compared.

RESULTS: According to the Wilcoxon test, it was found that for native CT and virtual unenhanced images from arterial phase of DECT we have p=0.148, for native CT and virtual unenhanced images from venous phase of DECT, p=0.072. The coefficient of intraclass correlation=0.984 (95% CI: [0.981; 0.990]) for virtual unenhanced images from arterial phase DECT, and coefficient of intraclass correlation=0.983 (95% CI: [0.973; 0.992]) for virtual unenhanced images from venous phase of DECT.

DISCUSSION: According to the data of the presented study, the absence of a statistically significant difference between virtual unenhanced images and real native images is illustrated.

CONCLUSIONS: The absence of a statistically significant difference between the virtual unenhanced images obtained from the arterial and venous phases of contrast enhancement and the real native images allows using virtual unenhanced images instead of native images in the differential diagnosis of adrenal gland formations. This, in turn, will help to avoid reducing radiation exposure and reduce the scanning time.

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