Improved reproducibility of right ventricular volumes and function estimation from cardiac magnetic resonance images using level‐set models

Abstract

This study aims to assess whether an alternative method, that is based on volumetric surface detection (VoSD) without tracing and is totally free of geometric assumptions, can improve the reproducibility of right ventricular (RV) volume quantification from cardiac magnetic resonance (CMR) images, in comparison with a conventional disk-area technique. In a sample of 23 patients, with wide variability of RV end-diastolic volume (EDV: 47-131 ml), endsystolic volume (ESV: 20 -76 ml), and ejection fraction (EF: 29 -73%), using the standard method (Argus, Siemens) as the reference, the VoSD method showed good agreement for EDV, ESV, and EF estimations (correlation coefficient: 0.91, 0.94, and 0.94; Bland-Altman biases: 1 ml, 1 ml, and 0%; limits of agreement: ؎16 ml, ؎11 ml, and ؎11%, respectively). An analysis of the reproducibility of the two methods showed lower intraobserver variability for the VoSD method than for the conventional method, as evidenced by the coefficient of variability (CoV) values (2-6% vs. 8 -15%; P < 0.05). In addition, the VoSD method showed improved interobserver reproducibility (7-10% vs. 8 -15%), but the difference was statistically significant only for EF estimation variability (8 vs. 15%, P < 0.05). In conclusion, the newly developed VoSD technique allows accurate measurements of RV volumes and function, and appears to be more reproducible than the conven- Cardiac magnetic resonance (CMR) is the gold standard for assessing left ventricle (LV) volume, function, and mass because of its excellent accuracy (1-3) and reproducibility (1,4 -7). Since it also offers three-dimensional (3D) acquisition capability, CMR is also well suited for assessing a chamber with a more complex shape, such as the right ventricle (RV). Indeed, relative to measurements of RV volume and mass, CMR has shown a good correlation with in vitro (8,9) and in vivo (3,8,10,11) techniques, and good in vivo reproducibility (1,7,8,(11)(12)(13).However, the reproducibility of measurements by the disk-area summation technique is better for the LV than the RV, particularly in terms of ejection fraction (EF) estimation (13).We sought to assess the clinical feasibility of an alternative method that does not involve geometric assumptions (14) and is based on volumetric reconstruction and semiautomated endocardial volumetric surface detection (VoSD) of the RV chamber. We expected this method, which has been shown to provide good boundary detection in echocardiographic (15,16) and CMR studies (17,18) of the LV, to provide more reproducible estimation of RV parameters than the conventional method. MATERIALS AND METHODS Study PopulationThe study was approved by the institutional review board. Twenty-three consecutive patients (20 males and three females, 65 Ϯ 16 years old) who had undergone CMR for various cardiac pathologies were included in the study. There were 10 patients with healed myocardial infarction, three with angina, eight with dilated cardiomyopathy, one with valvular disease, and one with arrhythmic disorders. To assess th...

Measuring the heart in pulmonary arterial hypertension (PAH): Implications for trial study size

“…In PAH, it appears that leaving analysis entirely to the observer's judgment by the manual method gives better results, though this takes longer and is likely to rely on the observer being experienced. In the future these deficiencies should be rectified with improvements in technology, such as that based on a volumetric surface detection (34), which will make semiautomated analysis the technique of choice.…”

Intra-observer and interobserver variability of biventricular function, volumes and mass in patients with congenital heart disease measured by CMR imaging

“…Catalano et al [ 23 ] and Corsi et al [ 24 ] reported on a technique for volumetric surface detection (VoSD) and quantification of biventricular volumes without tracing and geometric approximations. The VoSD method showed lower observer variation for all parameters compared to the short axis method.…”

“…The VoSD method showed lower observer variation for all parameters compared to the short axis method. Although limitations clearly exist, this technique might improve reproducibility of biventricular assessments [ 23 , 24 ].…”

Quantification of Right and Left Ventricular Function in Cardiac MR Imaging: Comparison of Semiautomatic and Manual Segmentation Algorithms

“…It is also rather important to provide the method with a high degree of automatism to favour a progressively more routine use. Volumetric 3D analysis should also be investigated [ 29 ]. Besides, the population of the study was limited.…”