Image quality and radiation exposure with a low tube voltage protocol for coronary CT angiography results of the PROTECTION II Trial.

Objectives: The purpose of this study was to evaluate image quality and radiation dose using a 100 kVp tube voltage scan protocol compared with standard 120 kVp for coronary computed tomography angiography (CTA).

Background: Concerns have been raised about radiation exposure during coronary CTA. The use of a 100 kVp tube voltage scan protocol effectively lowers coronary CTA radiation dose compared with standard 120 kVp, but it is unknown whether image quality is maintained.

[Evaluation of mitral regurgitation severity using a simplified method based on proximal flow convergence].

Introduction And Objectives: Calculation of the effective regurgitant orifice (ERO) is regarded as the most accurate way of assessing the severity of mitral regurgitation (MR), but the technique's complexity limits its use. Our objective was to modify and validate a previously published semiquantitative method of assessment based on measurement of the proximal isovelocity surface area (PISA) in order to adapt it to recent recommendations from American and European cardiology societies.

Methods: In the PISA method, maximum regurgitant flow (MRF) is a function of the radius and aliasing velocity (AV).