Screening the fetal heart for the presence of congenital heart disease (CHD) during routine obstetrical sonography has not translated to early identification of CHD for the majority of patients (Friedberg et al., 2009; Poole et al., 2013). Limitations have been identified in the methods used to assess the fetal heart. A number of leading experts have identified the need for a real-time assessment of the fetal heart compared with the convention of relying on static images only for interpretation (Mcgahan, Moon-grady, & Pahwa, 2007; Sklansky, 2007). In addition, a deep need has been identified for education to improve the examiner''s and interpreting physician''s understanding of the sonographic features of CHD (Friedberg et al., 2009; McBrien, Sands, Craig, Dornan, & Casey, 2010).Imaging the fetal heart is a challenging element of a routine obstetrical sonogram. The fetal heart is a very small, complex and highly dynamic structure with a normal heart rate ranging from 120-160 bpm (Fredouille, 2007). The expression of CHD varies considerably, depending on the specific congenital anomaly and the time at which the exam is performed. (Cook, Yates, & Anderson, 2004). Some severe forms of CHD including Transposition of the Great Arteries (TGA) can only be detected through visualization of the outflow tracts, while other forms such as Hypoplastic Left Heart Syndrome (HLHS) can be seen in the four chamber view (Chaoui, 2003).Although the practice guidelines for obstetric ultrasound imaging explicitly identify the anatomic structure that should be examined during screening, considerable variation in how these structures are assessed exists (ACR Guidelines and Standards Committee, American Institute of Ultrasound in Medicine, 2003)(American Institute of Ultrasound in Medicine, 2013). The majority of screening centers rely on a few static images to demonstrate the normalcy of fetal heart including a four chamber view and both outflow tracts. Alternative approaches have been identified and these include the use of cine-loops, Doppler imaging, and three dimensional imaging, as well as detailed anatomic planes (Chaoui & Heling, 2005; Chaoui & McEwing, 2003; Mcgahan et al., 2007).This PhD thesis includes three projects that have been completed to address potentially increasing the rate of CHD detection. The first project assessed the feasibility and efficacy of using cine-loop sweeps, grey-scale cine-loop sweeps and colour Doppler cine sweeps compared with static images only. The use of cine-loop sweeps was found to be the most effective and practical technique. The second project assessed the practicality of using cine-loop sweeps and a standardized assessment technique compared with static images only and demonstrated an increased detection rate of CHD. The third project assessed the efficacy of an online, tutorial-based tool for learning the standardized assessment technique of cine-loop sweeps used in the first two projects.Improving the detection rate of CHD during routine obstetrical sonography can be achieved with the use of a standardized assessment of cine-loop sweeps. The translation of this technique to clinical practice can be achieved using an online learning tool.
|Qualification||Doctor of Philosophy|
|Award date||01 Jul 2014|
|Place of Publication||Australia|
|Publication status||Published - 2015|