Computed tomography and magnetic resonance imaging in cystic fibrosis lung disease

Abstract

Computed tomography (CT) is the current “gold standard” for assessment of lung morphology and is so far the most reliable imaging modality for monitoring cystic fibrosis (CF) lung disease. CT has a much higher radiation exposure than chest x‐ray. The cumulative radiation dose for life‐long repeated CT scans has limited its use for CF patients as their life expectancy increases. Clearly, no dose would be preferable over low dose when the same or more relevant information can be obtained. Magnetic resonance imaging (MRI) is comparable to CT with regard to the detection of most morphological changes in the CF lung. It is thought to be less sensitive to detect small airway disease. At the same time, MRI is superior to CT when it comes to the assessment of functional changes such as altered pulmonary perfusion. The recommendation is to further reduce radiation dose related to the use of CT and to use MRI in the follow‐up of morphological changes where possible. J. Magn. Reson. Imaging 2010;32:1370–1378. © 2010 Wiley‐Liss, Inc.

MRI of the lung – state of the art

“…Compared with COPD, CF lung disease can be considered a "pluspathology" due to bronchial wall thickening, bronchial dilatation, and mucus plugging (25), which are easily identified with MRI (Figs. 1a and 5a).…”

Using hyperpolarized 3He MRI to evaluate treatment efficacy in cystic fibrosis patients

“…However, the ionizing radiation associated with CT limits its use, particularly for pediatric imaging or multiple imaging sessions to assess treatment efficacy over time (11). Lower dose CT has been developed (12,13), and this reduces the health risks of radiation, but the risks remain significant (14)(15)(16). In addition, CT cannot provide images of functional ventilation within the lung.…”

Imaging of Cystic Fibrosis Lung Disease and Clinical Interpretation

“…Age-adapted low-dose acquisitions with an effective radiation dose of less than 2 mSv even in adults are sufficient for the evaluation of morphological changes including ground glass opacities and mosaic perfusion [20]. A combined protocol of end-inspiratory with end-expiratory scans is generally recommended to enhance the sensitivity for small airway obstruction [21,22], and both acquisitions may be performed with similar exposure settings, but added radiation dose (• ▶ Table 1). At the same time, all technical potential available for dose reduction must be exploited, such as reduction of overbeaming, automatic tube current modulation, iterative reconstruction, etc.…”