Image quality and radiation dose comparison of prospectively triggered low-dose CCTA: 128-slice dual-source high-pitch spiral versus 64-slice single-source sequential acquisition

Purpose To analyze possible influencing factors on radiation exposure in pediatric chest CT using different approaches for radiation dose optimization and to determine major indicators for dose development. Materials and Methods In this retrospective study at a clinic with maximum care facilities including pediatric radiology, 1695 chest CT examinations in 768 patients (median age: 10 years; range: 2 days to 17.9 years) were analyzed. Volume CT dose indices, effective dose, size-specific dose estimate, automatic dose modulation (AEC), and high-pitch protocols (pitch ≥ 3.0) were evaluated by univariate analysis. The image quality of low-dose examinations was compared to higher dose protocols by non-inferiority testing. Results Median dose-specific values annually decreased by an average of 12 %. High-pitch mode (n = 414) resulted in lower dose parameters (p < 0.001). In unenhanced CT, AEC delivered higher dose values compared to scans with fixed parameters (p < 0.001). In contrast-enhanced CT, the use of AEC yielded a significantly lower radiation dose only in patients older than 16 years (p = 0.04). In the age group 6 to 15 years, the values were higher (p < 0.001). The diagnostic image quality of low-dose scans was non-inferior to high-dose scans (2.18 vs. 2.14). Conclusion Radiation dose of chest CT was reduced without loss of image quality in the last decade. High-pitch scanning was an independent factor in this context. Dose reduction by AEC was limited and only relevant for patients over 16 years. Key Points Citation Format

Download Full-text

Image Quality and Radiation Dose of Lower Extremity CT Angiography in 128 Slice Dual-Source CT: Comparison of High Pitch and Low Pitch

Journal of the Korean Society of Radiology ◽

10.3348/jksr.2014.71.3.120 ◽

2014 ◽

Vol 71 (3) ◽

pp. 120 ◽

Cited By ~ 1

Author(s):

Jung Hwan Park ◽

Ki Seok Choo ◽

Ung Bae Jeon ◽

Seung Kug Baik ◽

Yong Woo Kim ◽

...

Keyword(s):

Image Quality ◽

Radiation Dose ◽

Lower Extremity ◽

Ct Angiography ◽

Dual Source Ct ◽

High Pitch ◽

Dual Source

Download Full-text

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

Scientific Reports ◽

10.1038/s41598-019-52454-5 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Robert Forbrig ◽

Michael Ingrisch ◽

Robert Stahl ◽

Katharina Stella Winter ◽

Maximilian Reiser ◽

...

Keyword(s):

Image Quality ◽

Radiation Dose ◽

Third Generation ◽

Obese Patients ◽

Dual Source Ct ◽

High Pitch ◽

Subjective Image Quality ◽

Dual Source ◽

Group A

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.

Download Full-text