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

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

Model-based iterative reconstruction in paediatric head computed tomography : a pilot study on dose reduction in children

Purpose: To evaluate the potential of model-based iterative reconstruction (MBIR) on dose reduction and image quality in children undergoing computed tomography (CT) head examinations. Material and methods: This prospective study was approved by the institutional ethics committee. A total of 88 children (age range of 5 to 16 years) with a history of seizures underwent contrast-enhanced CT scan. Forty-one children underwent CT study according to the MBIR technique, while 47 children underwent CT of the head with the non-MBIR protocol. Images were reviewed by 2 blinded paediatric radiologists in a random order. Mean dose-length product, CT dose index (CTDI) volume, and mean effective dose were recorded for both groups. Image quality, image noise, and diagnostic acceptability of 2 image sets were also recorded. Results: In the MBIR group, the mean dose-length product was reduced by 79.8%; the mean CTDI volume was reduced by 88.5%, while the mean effective dose was reduced by 81% when compared to the non-MBIR group. No significant difference was seen in diagnostic acceptability, image noise, and image quality between the 2 groups. Conclusions: MBIR technique is highly effective in reducing radiation dose in paediatric head CT examinations without any significant difference in image quality, image noise, and diagnostic acceptability

Evaluation of coronary arteries in congenital heart disease in children : diagnostic comparison of electrocardiogram-gated and non-electrocardiogram-gated computed tomography cardiac angiograpy

Purpose: To compare the visualization and anatomy of coronary arteries in children (≤ 2 years) with congenital heart disease (CHD) on non-electrocardiogram (ECG)-gated and ECG-gated computed tomography angiography (CTA). Material and methods: In this retrospective study, approved by the Ethics Committee of our institute, evaluation of coronary arteries in CHD was performed in 40 children on non-ECG-gated CTA and in 42 children on ECG-gated CTA. The origin and course of the right coronary artery (RCA), left main coronary artery (LMCA), left anterior descending (LAD) artery, and left circumflex (LCX) artery were evaluated by 2 paediatric radiologists independently. Results: ECG-gated CT scans yielded increased (additional) visualization of all the coronary arteries, when compared to non-ECG-gated CT scans. The RCA, LMCA, LAD artery, and LCX artery were visualized in 47.5%, 62.5%, 55%, and 32.5% of children, respectively, on non-ECG-gated studies, while they were visualized in 64.3%, 92.8%, 80.9%, and 62% children, respectively, on ECG-gated studies. The coronary artery anatomical variations were also supplementarily detected more in the ECG-gated group (23.8%) than in the non-ECG gated group (2.5%). Conclusions: ECG-gated CT cardiac angiography studies yield enhanced diagnostic outcomes for the evaluation of the coronary arteries in comparison to non-ECG-gated studies

Partial anomalous hepatic venous drainage into left-sided atrium with right isomerism: A case report with review of literature

Right isomerism, also known as Ivemark syndrome, is an unusual degree of symmetry of some of the abdominothoracic viscera reflecting bilateral right-sidedness. We report an exceedingly rare occurrence of anomalous drainage of the left hepatic vein to the left-sided atrium in a patient of right isomerism. With this case report, we further endorse that the isomerism of atrium might extend beyond the appendages, a view that has been long dismissed by the existing literature

Lung magnetic resonance imaging for pneumonia in children

Technical factors have historically limited the role of MRI in the evaluation of pneumonia in children in routine clinical practice. As imaging technology has advanced, recent studies utilizing practical MR imaging protocols have shown MRI to be an accurate potential alternative to CT for the evaluation of pneumonia and its complications. This article provides up-to-date MR imaging techniques that can be implemented in most radiology departments to evaluate pneumonia in children. Imaging findings in pneumonia on MRI are also reviewed. In addition, the current literature describing the diagnostic performance of MRI for pneumonia is discussed. Furthermore, potential risks and limitations of MRI for the evaluation of pneumonia in children are described

Opaque hemithorax in a child: The eyes see what the mind suspects

Background: Children with acute febrile respiratory illnesses are commonly seen in the emergency department. Apart from the initial stabilization, they need to be assessed for the underlying cause, and clinicians should formulate differential diagnoses to start treatment. Radiological investigations including x-ray and ultrasonography are often used to narrow down the initial possibilities based on history and examination. A child presenting with an opaque hemithorax is one such scenario. Clinical Description: A 3-year-old boy presented with a short duration of fever, cough and respiratory distress. Examination showed rightward mediastinal shift with dull percussion note and reduced breath sounds over the left hemithorax, along with congested neck veins, stridor and left sided wheeze. Chest x-ray showed an opacified left hemithorax and ultrasonography suggested moderate pleural effusion. Management: Complicated pneumonia with parapneumonic effusion (or empyema) was considered, but a diagnostic pleural tap was dry. The possibilities were revised to include cystic space occupying lesions with mediastinal compression. Computed tomography of the chest confirmed a mass lesion with predominantly cystic components. The patient underwent surgical excision, and histopathology showed pleuropulmonary blastoma. Conclusion: Although respiratory infections are common in childhood, clinical evaluation and judicious use of imaging modalities can uncover less common conditions. Although bedside ultrasonography is a handy tool in the emergency department, it is not infallible