Lung magnetic resonance imaging in pulmonary hydatid in children.

Dear Editor,

We read with interest the article entitled “The spectrum of imaging findings in pulmonary hydatid disease and the additive value of T2-weighted magnetic resonance imaging in its diagnosis” by Naseer et al. [1]. The authors described the spectrum of imaging findings in pulmonary echinococcosis and studied the additive value of T2-weighted magnetic resonance imaging (MRI) in the characterisation of pulmonary hydatid disease. They concluded that “Most of the pulmonary hydatid cysts can be diagnosed on computed tomography (CT); however, sometimes the findings may be indeterminate or atypical, leading to a diagnostic dilemma. MRI, owing to its ability to demonstrate hypointense endocyst, can act as a useful adjunct to correctly diagnose hydatid cyst or suggest an alternative diagnosis”.

We wish to highlight that recent publications have highlighted the potential role of MRI as a radiation-free alternative to multidetector computed tomography (MDCT) for imaging in children, particularly those with different kinds of pulmonary infections and compromised immune systems [2-7]. Technological advances in MRI and faster acquisition sequences help in high-quality MRI of the lung [2-7]. Lung MRI has been reported to have higher diagnostic accuracy and sensitivity in the detection of pulmonary hydatids than computed tomography [2,3].

Sodhi et al. [2] prospectively investigated the diagnostic accuracy and added value of fast MRI in 28 children (5-17 years) for evaluating pulmonary hydatid disease by comparing MRI findings with MDCT findings. The combined total scanning time for all 4 MRI sequences used in this study was approximately 2-5 minutes only. The accuracy of fast MRI and MDCT for detecting pulmonary hydatid cysts was found to be 92.86%. There was no difference between fast MRI and MDCT for accurately detecting pulmonary hydatid cysts (p < 0.001). Internal membranes were detected in 11 of 28 patients (39.28%) with fast MRI, and in 3 of 28 patients (10.71%) with MDCT. Almost perfect interobserver agreement was present between the 2 independent reviewers (κ = 1). They concluded that fast MRI without intravenous contrast is comparable to MDCT for accurately detecting lung cysts in paediatric patients with pulmonary hydatid disease. However, fast MRI provided a 28.6% increase in added diagnostic value by showing internal membranes of cysts, which are specific to pulmonary hydatid disease. Therefore, fast MRI should be considered in lieu of MDCT as a primary problem-solving radiation-free imaging modality after initial chest radiography in paediatric patients with clinically suspected pulmonary hydatid disease.