Multistage three‐dimensional UTE lung imaging by image‐based self‐gating
2015; Wiley; Volume: 75; Issue: 3 Linguagem: Inglês
10.1002/mrm.25673
ISSN1522-2594
AutoresMarta Tibiletti, Jan Paul, Andrea Bianchi, Stefan Wundrak, Wolfgang Rottbauer, Detlef Stiller, Volker Rasche,
Tópico(s)Medical Imaging Techniques and Applications
ResumoPurpose To combine image‐based self‐gating (img‐SG) with ultrashort echo time (UTE) three‐dimensional (3D) acquisition for multistage lung imaging during free breathing. Methods Three k‐space ordering schemes (modified spiral pattern, quasirandom numbers and multidimensional Golden Angle) providing uniform coverage of k‐space were investigated for providing low‐resolution sliding‐window images for image‐based respiratory self‐gating. The performance of the proposed techniques were compared with the conventional spiral pattern and standard DC‐based self‐gated methods in volunteers during free breathing. Results Navigator‐like respiratory signals were successfully extracted from the sliding‐window data by monitoring the lung–liver interface displacement. A temporal resolution of 588 ms was adequate to retrieve gating signals from the lung–liver interface. Images reconstructed with the img‐SG technique showed significantly better sharpness and apparent diaphragm excursion than any of the DC‐SG methods. Direct comparison of the three implemented ordering schemes did not demonstrate any clear superiority of one with respect to the others. Conclusion Image‐based respiratory self gating in UTE 3D lung images allows successful retrospective respiratory gating, also enabling reconstruction of intermediate respiratory stages. Magn Reson Med 75:1324–1332, 2016. © 2015 Wiley Periodicals, Inc.
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