Evaluation of image quality and patient safety: Paired inspiratory and expiratory MDCT assessment of tracheobronchomalacia in paediatric patients under general anaesthesia with breath-hold technique

Technique, pitfalls, quality, radiation dose and findings of dynamic 4-dimensional computed tomography for airway imaging in infants and children

This retrospective review of 33 children's dynamic 4-dimensional (4-D) computed tomography (CT) images of the airways, performed using volume scanning on a 320-detector array without anaesthesia (free-breathing) and 1.4-s continuous scanning, was undertaken to report technique, pitfalls, quality, radiation doses and findings. Tracheobronchomalacia (airway diameter collapse >28%) was recorded. Age-matched routine chest CT scans and bronchograms acted as benchmarks for comparing effective dose. Pitfalls included failure to administer intravenous contrast, pull back endotracheal tubes and/or remove nasogastric tubes. Twenty-two studies (67%) were diagnostic. Motion artefact was present in 16 (48%). Mean effective dose: dynamic 4-D CT 1.0 mSv; routine CT chest, 1.0 mSv, and bronchograms, 1.4 mSv. Dynamic 4-D CT showed tracheobronchomalacia in 20 patients (61%) and cardiovascular abnormalities in 12 (36%). Fourteen children (70%) with tracheobronchomalacia were managed successfully by optimising conservative management, 5 (25%) underwent surgical interventions and 1 (5%) died from the presenting disorder.

Magnetic resonance imaging of pediatric lung parenchyma, airways, vasculature, ventilation, and perfusion: state of the art

Magnetic resonance (MR) imaging is a noninvasive imaging modality, particularly attractive for pediatric patients given its lack of ionizing radiation. Despite many advantages, the physical properties of the lung (inherent low signal-to-noise ratio, magnetic susceptibility differences at lung-air interfaces, and respiratory and cardiac motion) have posed technical challenges that have limited the use of MR imaging in the evaluation of thoracic disease in the past. However, recent advances in MR imaging techniques have overcome many of these challenges. This article discusses these advances in MR imaging techniques and their potential role in the evaluation of thoracic disorders in pediatric patients.

Advanced large airway CT imaging in children: evolution from axial to 4-D assessment

Continuing advances in multidetector computed tomography (MDCT) technology are revolutionizing the non-invasive evaluation of congenital and acquired large airway disorders in children. For example, the faster scanning time and increased anatomical coverage that are afforded by MDCT are especially beneficial to children. MDCT also provides high-quality multiplanar 2-dimensional (2-D), internal and external volume-rendering 3-dimensional (3-D), and dynamic 4-dimensional (4-D) imaging. These advances have enabled CT to become the primary non-invasive imaging modality of choice for the diagnosis, treatment planning, and follow-up evaluation of various large airway disorders in infants and children. It is thus essential for radiologists to be familiar with safe and effective techniques for performing MDCT and to be able to recognize the characteristic imaging appearances of large airway disorders affecting children.