Magnetic resonance imaging acquisition techniques intended to decrease movement artefact in paediatric brain imaging: a systematic review

Abstract

Attaining paediatric brain images of diagnostic quality can be difficult because of young age or neurological impairment. The use of anaesthesia to reduce movement in MRI increases clinical risk and cost, while CT, though faster, exposes children to potentially harmful ionising radiation. MRI acquisition techniques that aim to decrease movement artefact may allow diagnostic paediatric brain imaging without sedation or anaesthesia. We conducted a systematic review to establish the evidence base for ultra-fast sequences and sequences using oversampling of k-space in paediatric brain MR imaging. Techniques were assessed for imaging time, occurrence of movement artefact, the need for sedation, and either image quality or diagnostic accuracy. We identified 24 relevant studies. We found that ultra-fast techniques had shorter imaging acquisition times compared to standard MRI. Techniques using oversampling of k-space required equal or longer imaging times than standard MRI. Both ultra-fast sequences and those using oversampling of k-space reduced movement artefact compared with standard MRI in unsedated children. Assessment of overall diagnostic accuracy was difficult because of the heterogeneous patient populations, imaging indications, and reporting methods of the studies. In children with shunt-treated hydrocephalus there is evidence that ultra-fast MRI is sufficient for the assessment of ventricular size.

Diagnostic Performance of a 10-Minute Gadolinium-Enhanced Brain MRI Protocol Compared with the Standard Clinical Protocol for Detection of Intracranial Enhancing Lesions

“…In accordance with our results, previous studies demonstrated the benefits of using parallel imaging sequences in ischemic stroke and pediatric central nervous system disorders, 3,29,30 with consistently reduced acquisition times and comparable image quality. In the study of Nael et al, 29 postcontrast sequences, MR angiography and dynamic susceptibility contrast perfusion, were tested in an acute stroke setting.…”

“…Consequently, in the past decade, there has been a concerted effort to develop fast and ultrafast MR imaging protocols. [1][2][3][4][5][6][7] For many years, continual development of new scanners with stronger gradients and the improvement of coil technology, [8][9][10] allied with a number of emerging fast imaging techniques, has allowed substantial reduction in MR imaging scan times. 1,[11][12][13] More recently, the development of parallel imaging, a robust method for accelerating MR imaging data acquisitions based on obtaining simultaneous information from arrays of coils, allowing decreased filling of k-space lines, has been the preferred method for decreasing acquisition times.…”

CT scan exposure in children with ventriculo-peritoneal shunts: single centre experience and review of the literature

“…Young children in particular find long MR acquisition times difficult to tolerate. More recently, faster MRI sequences have been developed to try and overcome this problem [38]. Further limitations to the use of MRI scanning in suspected shunt malfunction would be both the cost, as well as access to an MRI scanner.…”

Anesthetic-Related Neurotoxicity and Neuroimaging in Children: A Call for Conversation

“…The frequency of unsedated MRIs in neonates is increasing, especially as MRI acquisition techniques advance to diminish movement artifact. 58 Ultra-fast techniques are available for some diagnostic studies, and evidence supports the use of ultra-fast MRI for the assessment of ventricular size in children with shunttreated hydrocephalus. 58,59 Finally, consideration may be given to combining multiple studies and procedures requiring anesthesia in children to limit exposure; however, an individual risk-benefit analysis in the context of the present health care practice may not support this as risk of transport and additional anesthesia exposure between studies may outweigh the perceived benefit.…”