Gabriel C Camargo1, Fernanda Erthal2, Leticia Sabioni3, Filipe Penna4, Ralph Strecker5, Michaela Schmidt6, Michael O Zenge7, Ronaldo de S L Lima8, Ilan Gottlieb9. 1. Casa de Saúde São José, Rio de Janeiro, Brazil; Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. Electronic address: gabccamargo@gmail.com. 2. Clínica de Diagnóstico por Imagem, Rio de Janeiro, Brazil. Electronic address: fmerthal@yahoo.com.br. 3. Clínica de Diagnóstico por Imagem, Rio de Janeiro, Brazil. Electronic address: leticiasabioni@hotmail.com. 4. Clínica de Diagnóstico por Imagem, Rio de Janeiro, Brazil. Electronic address: filipepenna@me.com. 5. Siemens Healthcare Diagnósticos S.A., São Paulo, Brazil. Electronic address: ralph.strecker@siemens.com. 6. Siemens Healthcare GmbH, Erlangen, Germany. Electronic address: michaela.schmidt@siemens.com. 7. Siemens Healthcare GmbH, Erlangen, Germany. Electronic address: michael.zenge@siemens.com. 8. Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Clínica de Diagnóstico por Imagem, Rio de Janeiro, Brazil. Electronic address: ronlima@hotmail.com. 9. Casa de Saúde São José, Rio de Janeiro, Brazil; National Institute of Cardiology, Rio de Janeiro, Brazil. Electronic address: ilangottlieb@gmail.com.
Abstract
BACKGROUND: Segmented cine imaging with a steady-state free-precession sequence (Cine-SSFP) is currently the gold standard technique for measuring ventricular volumes and mass, but due to multi breath-hold (BH) requirements, it is prone to misalignment of consecutive slices, time consuming and dependent on respiratory capacity. Real-time cine avoids those limitations, but poor spatial and temporal resolution of conventional sequences has prevented its routine application. We sought to examine the accuracy and feasibility of a newly developed real-time sequence with aggressive under-sampling of k-space using sparse sampling and iterative reconstruction (Cine-RT). METHODS: Stacks of short-axis cines were acquired covering both ventricles in a 1.5T system using gold standard Cine-SSFP and Cine-RT. Acquisition parameters for Cine-SSFP were: acquisition matrix of 224×196, temporal resolution of 39ms, retrospective gating, with an average of 8 heartbeats per slice and 1-2 slices/BH. For Cine-RT: acquisition matrix of 224×196, sparse sampling net acceleration factor of 11.3, temporal resolution of 41ms, prospective gating, real-time acquisition of 1 heart-beat/slice and all slices in one BH. LV contours were drawn at end diastole and systole to derive LV volumes and mass. RESULTS: Forty-one consecutive patients (15 male; 41±17years) in sinus rhythm were successfully included. All images from Cine-SSFP and Cine-RT were considered to have excellent quality. Cine-RT-derived LV volumes and mass were slightly underestimated but strongly correlated with gold standard Cine-SSFP. Inter- and intra-observer analysis presented similar results between both sequences. CONCLUSIONS: Cine-RT featuring sparse sampling and iterative reconstruction can achieve spatial and temporal resolution equivalent to Cine-SSFP, providing excellent image quality, with similar precision measurements and highly correlated and only slightly underestimated volume and mass values.
BACKGROUND: Segmented cine imaging with a steady-state free-precession sequence (Cine-SSFP) is currently the gold standard technique for measuring ventricular volumes and mass, but due to multi breath-hold (BH) requirements, it is prone to misalignment of consecutive slices, time consuming and dependent on respiratory capacity. Real-time cine avoids those limitations, but poor spatial and temporal resolution of conventional sequences has prevented its routine application. We sought to examine the accuracy and feasibility of a newly developed real-time sequence with aggressive under-sampling of k-space using sparse sampling and iterative reconstruction (Cine-RT). METHODS: Stacks of short-axis cines were acquired covering both ventricles in a 1.5T system using gold standard Cine-SSFP and Cine-RT. Acquisition parameters for Cine-SSFP were: acquisition matrix of 224×196, temporal resolution of 39ms, retrospective gating, with an average of 8 heartbeats per slice and 1-2 slices/BH. For Cine-RT: acquisition matrix of 224×196, sparse sampling net acceleration factor of 11.3, temporal resolution of 41ms, prospective gating, real-time acquisition of 1 heart-beat/slice and all slices in one BH. LV contours were drawn at end diastole and systole to derive LV volumes and mass. RESULTS: Forty-one consecutive patients (15 male; 41±17years) in sinus rhythm were successfully included. All images from Cine-SSFP and Cine-RT were considered to have excellent quality. Cine-RT-derived LV volumes and mass were slightly underestimated but strongly correlated with gold standard Cine-SSFP. Inter- and intra-observer analysis presented similar results between both sequences. CONCLUSIONS:Cine-RT featuring sparse sampling and iterative reconstruction can achieve spatial and temporal resolution equivalent to Cine-SSFP, providing excellent image quality, with similar precision measurements and highly correlated and only slightly underestimated volume and mass values.
Authors: Bradley D Allen; Maria L Carr; Michael Markl; Michael O Zenge; Michaela Schmidt; Mariappan S Nadar; Bruce Spottiswoode; Jeremy D Collins; James C Carr Journal: Eur Radiol Date: 2018-01-30 Impact factor: 5.315