Diagnostic accuracy of magnetic resonance imaging in the evaluation of pulmonary infections in immunocompromised patients

Abstract

Purpose: To evaluate the accuracy of magnetic resonance imaging (MRI) for diagnosing pulmonary infections in immunocompromised adults. Material and methods: Computed tomography (CT) and MRI chest were performed in 35 immuno-compromised patients suspected of pulmonary infection. The MRI sequences that were performed included axial and coronal T2 half-Fourier acquisition single-shot turbo spin-echo (HASTE), spectrally attenuated inversion recovery (SPAIR), true fast imaging with steady-state free precession (TRUFI), and three-dimensional fast low angle shot (3D FLASH) using breath-hold and respiratory triggered BLADE (proprietary name for periodically rotated overlapping parallel lines with enhanced reconstruction). The presence of nodules, consolidations, and ground-glass opacities was evaluated. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for MRI using CT scan as a reference standard. Results: The sensitivity of MRI in nodule detection was 50% overall and 75% for nodules measuring more than 5 mm. Consolidation was detected with 100% sensitivity. Sensitivity and PPV for the detection of ground-glass opacities (GGOs) were 77.7% and 53.8%, respectively. T2 HASTE axial had the fewest image artefacts. Respiratory triggered MR pulse sequence did not add any significant diagnostic information as compared to the non-respiratory triggered MR pulse sequences. Conclusions: Sensitivity for detecting small nodules and GGOs on MR is poor; CT scan remains the imaging modality of choice for the evaluation of pulmonary infections in immunocompromised patients. However, MRI can be used in the follow-up imaging of these patients.

Thorax Magnetic Resonance Imaging Findings in Patients with Coronavirus Disease (COVID-19)

“…Moreover, the presence of early-stage necrotic pneumonia, which could not be shown by contrast-enhanced CT in 25% of patients, was demonstrated by MRI (27). In subsequent studies with a similar patient group, MRI was found to be very useful diagnostic tool, especially in its use during follow-up (28,29); furthermore, MRI was reported to be promising in detecting nodules in these patients (30). In our study, the sensitivity of MRI in nodule detection was 91.67%, and its specificity was 100%.…”

Appearance of COVID-19 pneumonia on 1.5 T TrueFISP MRI

“…Regarding opacities, the authors of several other studies have also reported that the sensitivity of MRI is equivalent to that of CT for the detection of consolidations, although not for ground-glass opacities, some of which cannot be seen on MRI (16,24) . Recently, Singh et al (21) evaluated the diagnostic accuracy of MRI for respiratory infections in immunocompromised patients. Their MRI protocol, like ours, included a TrueFISP sequence, and the authors found it to have a sensitivity of 100% for the detection of consolidations and of only 16.6% for the detection of ground-glass opacities.…”

“…Lung abnormalities observed on MRI were described according to the current literature on the subject, which adopts the CT terminology outlined in the Fleischner Society glossary. For instance, we defined ground-glass opacities as a hazy increase in signal intensity in the lung, with preserved bronchial and vascular margins (14,(16)(17)(18)(19)21,22) . The two readers evaluated the distribution of the pulmonary findings (unilateral vs. bilateral; unilobar vs. multilobar; affected lobes; involvement of upper, middle, and lower zones; peripheral or central lung involvement; anterior or posterior lung involvement; and subpleural sparing), as well as their opacity (groundglass opacities, consolidation, and interlobular/intralobular septal thickening) and appearance (patchy/segmental, rounded, crazy-paving, halo/reversed halo, linear/reticular, and air bronchogram).…”

Practical protocol for lung magnetic resonance imaging and common clinical indications

“…Given the only slightly inferior sensitivity for pulmonary nodules compared to CT, MRI might be recommended for long-term follow-up of children and young adults after malignancies with potential mediastinal and pulmonary metastases, e.g., in children with seminoma. For this purpose, a threshold size of 4-5 mm can be expected for pulmonary nodule detection with MRI [33,[70][71][72] (Fig. 11).…”