Imaging Quality Evaluation of Low Tube Voltage Coronary CT Angiography Using Low Concentration Contrast Medium

Abstract

PurposeTo compare the image quality of prospectively ECG-gated low voltage coronary computed tomography angiography (CTA) with an administration of low concentration contrast medium.Method and MaterialsA total of 101 patients, each with a heart rate below 65 beats per minute (BPM), underwent a prospectively ECG-gated axial scan in CT coronary angiography on a 64-slice CT scanner. All patients were allocated in three groups (group A: n=31, 80kVp, 300 mgI/ml; group B: n=34, 100kVp, 300 mgI/ml; group C: n=36, 120kVp, 370 mgI/ml). The CT attenuation values of aortic root (AR), left main coronary artery (LMA), right main coronary artery (RMA) and chest subcutaneous fat tissue were measured. The contrast-to-noise ratio (CNR) of AR, LMA and RMA were calculated according to the formulas below. The values of computed tomography dose index (CTDI) and dose-length product (DLP) were recorded. Image quality was assessed on a 5-point scale. The results were compared using the one-way ANOVA and rank sum tests.ResultsThe values of CNR and SNR for vessels in group A and group B were not significantly different from group C (each p > 0.05). The effective radiation dose in group A (1.51±0.70 mSv) and group B (2.59±1.24 mSv) were both lower than group C (4.92±2.82 mSv) (each p < 0.05). There was no significant difference among the image quality scores of group A (4.10±0.41), group B (3.90±0.48) and group C (4.04±0.36) (each P > 0.05).ConclusionLow tube voltage coronary CT angiography using low concentration contrast medium does not affect the imaging quality for assessing the coronary arteries compared with high voltage coronary CT angiography using high concentration contrast medium. Meanwhile low concentration contrast medium allowed 47-69% of radiation dose reduction.

Personalization of CM Injection Protocols in Coronary Computed Tomographic Angiography (People CT Trial)

“…e injection protocols were defined with help of a formula, which has been explained extensively elsewhere [20] and can be found in Appendix 1. Besides personalization to these patient characteristics, the injection protocol was adapted to the tube voltage, as described in previous studies [21][22][23][24][25]. e following formulas were used: With BW in kg and L � length in cm (iii) CO: flow rate � 0.008916 * kV * CO (b) CO according to an adapted Katori formula [27] CO � (4.874 − 0.023 * age) * BSA With age in years and BSA � body surface area e formulas shown above determined the flow rates for both test bolus and main bolus.…”

Low tube voltage prospectively ECG-triggered coronary CT angiography: a systematic review of image quality and radiation dose

“…Therefore, only 20 studies were finally selected for analysis. [15][16][17][18][19][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41] A detailed overview of the inclusion and data extraction processes is shown in Figure 1.…”

“…Whereas for triphasic injection, three distinct boluses were used; an initial undiluted contrast bolus followed by a CM and saline mixture, and then completed by a saline flush. Compared to 120 kVp, CM reduction was applied in seven studies at 80 kVp [17][18][19]31,33,38,41 and eight studies at 100 kVp. 27,[34][35][36][37][38][39]41 However, only two studies at 80 kVp, 18,19 and five studies at 100 kVp 34,35,37,39,41 reported similar vessel contrast enhancement compared to those at 120 kVp.…”

Subjective Imaging Effect Assessment for Intelligent Imaging Terminal Design: a Method for Engineering Site

“…For example, the International Telecommunication Union (ITU) has formulated lots of international standards to implement the subjective image quality assessment for some purposes [5][6][7]. And according to different application fields, the SIEA can be used in the medical imaging terminal research [8], the mobile device design [9], the computer science study [10], and the communication equipment development [11], etc. In terms of different research targets, it also can be used for the medical image [12], the facsimile image [13], the compressed image [14], the segmented image [15], the stereoscopic image [16], the omnidirectional image [17], and the remote image [18], etc.…”