Radiation dose and image quality of high-pitch emergency abdominal CT in obese patients using third-generation dual-source CT (DSCT)

Robert Forbrig,Christoph G. Trumm,Maximilian Reiser,Michael Ingrisch,Robert Stahl,Katharina Stella Winter

doi:10.1038/s41598-019-52454-5

Robert Forbrig, Christoph G. Trumm + Show 4 more

Open Access

https://doi.org/10.1038/s41598-019-52454-5

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Abstract

In this third-generation dual-source CT (DSCT) study, we retrospectively investigated radiation dose and image quality of portal-venous high-pitch emergency CT in 60 patients (28 female, mean age 56 years) with a body mass index (BMI) ≥ 30 kg/m2. Patients were dichotomized in groups A (median BMI 31.5 kg/m2; n = 33) and B (36.8 kg/m2; n = 27). Volumetric CT dose index (CTDIvol), size-specific dose estimate (SSDE), dose length product (DLP) and effective dose (ED) were assessed. Contrast-to-noise ratio (CNR) and dose-independent figure-of-merit (FOM) CNR were calculated. Subjective image quality was assessed using a five-point scale. Mean values of CTDIvol, SSDE as well as normalized DLP and ED were 7.6 ± 1.8 mGy, 8.0 ± 1.8 mGy, 304 ± 74 mGy * cm and 5.2 ± 1.3 mSv for group A, and 12.6 ± 3.7 mGy, 11.0 ± 2.6 mGy, 521 ± 157 mGy * cm and 8.9 ± 2.7 mSv for group B (p < 0.001). CNR of the liver and spleen as well as each calculated FOM CNR were significantly higher in group A (p < 0.001). Subjective image quality was good in both groups. In conclusion, third-generation abdominal high-pitch emergency DSCT yields good image quality in obese patients. Radiation dose increases in patients with a BMI > 36.8 kg/m2.

Highlights

Obesity, which is defined as a body mass index (BMI) of at least 30 kg/m2, represents a growing issue in the western societies[1]
In the present study we investigated radiation dose and image quality of portal-venous high-pitch emergency computed tomography (CT) of the abdomen in obese patients on a third-generation dual-source CT (DSCT) scanner
As the high-pitch dual-source mode of third-generation DSCT allows for a shorter CT acquisition time[10], this technique probably further optimizes radiation dose efficacy in comparison to a standard-pitch protocol[8,9,10,26,27]

Summary

Introduction

Obesity, which is defined as a body mass index (BMI) of at least 30 kg/m2, represents a growing issue in the western societies[1]. The aim of this study was to evaluate the impact of a high-pitch CT acquisition protocol on radiation dose and image quality in obese patients, who received a portal-venous emergency CT of the abdomen on a third-generation DSCT scanner.

Results

Conclusion