Cardiac three-dimensional rotational angiography can be performed with low radiation dose while preserving image quality

Background Computed tomography (CT) of the left atrium (LA) is performed prior to pulmonary vein isolation (PVI) to improve success of circumferential ablation for atrial fibrillation. The ablation procedure itself exposes patients to substantial radiation doses, therefore radiation dose reduction in pre-ablational imaging is of concern. Purpose To assess and compare diagnostic performance of low-radiation dose preprocedural CT in patients scheduled for PVI using two types of reconstruction algorithms. Material and Methods Forty-six patients (61 ± 10 years) scheduled for PVI were enrolled in this study irrespective of body-mass-index or cardiac rhythm at examination. An electrocardiographically triggered dual-source CT scan was performed. Filtered back projection (FBP) and iterative reconstruction (IR) algorithms were applied. Images were integrated into an electroanatomic mapping (EAM) system. Subjective image quality was scored independently by two readers on a five-point scale for both reconstruction algorithms (1 = excellent to 5 = non-diagnostic). Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and effective radiation dose were calculated. Results Data acquisition and EAM integration were successful in all patients. Median image quality score was 1 for both FBP (quartiles = 1, 1.62; range = 1–3) and IR (quartiles = 1, 1.5; range = 1–3). Mean SNR was 7.61 ± 2.14 for FBP and 9.02 ± 2.69 for IR. Mean CNR was 5.92 ± 1.80 for FBP and 6.95 ± 2.29 for IR. Mean effective radiation dose was 0.3 ± 0.1 mSv. Conclusion At a radiation dose of 0.3 ± 0.1 mSv, high-pitch dual-source CT yields LA images of consistently high quality using both FBP and IR. IR raises SNR and CNR without significantly improving subjective image quality.

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Three‐dimensional rotational angiography of transplanted renal arteries: influence of an extended angle of rotation on beam‐hardening artifacts

Acta Radiologica ◽

10.1080/02841850510020851 ◽

2005 ◽

Vol 46 (2) ◽

pp. 170-176 ◽

Cited By ~ 7

Author(s):

G. Hagen ◽

J. Wadström ◽

L. G. Eriksson ◽

P. Magnusson ◽

M. Magnusson ◽

...

Keyword(s):

Renal Function ◽

Image Quality ◽

Renal Artery ◽

Statistical Difference ◽

Three Dimensional ◽

Arterial Occlusion ◽

Balloon Occlusion ◽

Rotational Angiography ◽

Beam Hardening ◽

Angle Of Rotation

Purpose: To investigate whether three‐dimensional rotational angiography (3D‐RA) of the transplant renal artery performed with an extended angle of rotation can reduce beam‐hardening artifacts in 3D reconstructed images without image quality being lost or side effects to the transplanted kidney being increased. Material and Methods: 3D‐RA with a C‐arm rotation of 180° was performed consecutively in 12 renal transplanted patients with suspicion of renal artery stenosis. A 1.7‐mm balloon occlusion catheter was placed using the crossover technique and this was compared to a protocol with 160° rotation and a traditional 1.4‐mm catheter in 10 patients. The occurrence of beam‐hardening artifacts was registered and the effects of the reduced contrast load on image quality and of arterial occlusion on renal function were assessed. Results: The extended angle of rotation, from 160° to 180°, reduced the beam‐hardening artifacts. Artifacts were observed in 4/11 patients (36%) in the study group and in all 10 (100%) of the controls. There was no statistical difference regarding image quality between the two protocols. Renal function was equally affected in both protocols. Conclusion: 3D‐RA with an extended C‐arm rotation reduced the beam‐hardening artifacts. Image quality was not reduced despite the reduced contrast medium load. The different protocols had no effect on patient outcome.

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Pilot Study on Image Quality and Radiation Dose of CT Colonography with Adaptive Iterative Dose Reduction Three-Dimensional

PLoS ONE ◽

10.1371/journal.pone.0117116 ◽

2015 ◽

Vol 10 (1) ◽

pp. e0117116 ◽

Cited By ~ 1

Author(s):

Hesong Shen ◽

Dan Liang ◽

Mingyue Luo ◽

Chaijie Duan ◽

Wenli Cai ◽

...

Keyword(s):

Pilot Study ◽

Image Quality ◽

Radiation Dose ◽

Dose Reduction ◽

Ct Colonography ◽

Three Dimensional

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Performance Evaluation of Two Iterative Reconstruction Algorithms--MBIR and ASIR, in Low Radiation Dose and Low Contrast Dose Abdominal CT in Children

10.21203/rs.2.10744/v1 ◽

2019 ◽

Author(s):

Jihang Sun ◽

Lixin Yang ◽

Zuofu Zhou ◽

Dan Zhang ◽

Wei Han ◽

...

Keyword(s):

Image Quality ◽

Radiation Dose ◽

Iterative Reconstruction ◽

Image Noise ◽

Abdominal Ct ◽

Low Contrast ◽

Low Radiation Dose ◽

Contrast Dose ◽

Contrast Enhanced Ct ◽

Noise Ratio

Abstract Background The adverse effect of low-dose CT on image quality may be mitigated using iterative reconstructions. The purpose of this study was to evaluate the performance of the full model-based iterative reconstruction (MBIR) and adaptive statistical reconstruction (ASIR) algorithms in low radiation dose and low contrast dose abdominal contrast-enhanced CT (CECT) in children. Methods A total of 59 children (32 males and 27 females) undergoing low radiation dose (100kVp) and low contrast dose (270 mgI/ml) abdominal CECT were enrolled. The median age was 4.0 years (ranging from 0.3 to 13 years). The raw data were reconstructed with MBIR, ASIR and filtered back projection (FBP) algorithms into 6 groups (MBIR, 100%ASIR, 80%ASIR, 60%ASIR, 40%ASIR and FBP). The CT numbers, standard deviations, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of liver, pancreas, kidney and abdominal aorta were measured. Two radiologists independently evaluated the subjective image quality including the overall image noise and structure display ability on a 4-point scale with 3 being clinically acceptable. The measurements among the reconstruction groups were compared using one-way ANOVA. Results The overall image noise score and display ability were 4.00±0.00 and 4.00±0.00 with MBIR, and 3.27±0.33 and 3.25±0.43 with ASIR100%, respectively, which met the diagnostic requirement; other reconstructions couldn’t meet the diagnostic requirements. Compared with FBP images, the noise of MBIR images was reduced by 62.86%-65.73% for the respective organs (F=48.15-80.47, P<0.05), and CNR increased by 151.38%-170.69% (F=22.94-38.02, P<0.05). Conclusions MBIR or ASIR100% improves the image quality of low radiation dose and contrast dose abdominal CT in children to meet the diagnostic requirements, and MBIR has the best performance.

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