Chest MRI of patients with COVID-19.

During the pandemic of novel coronavirus infection (COVID-19), computed tomography (CT) showed its effectiveness in diagnosis of coronavirus infection. However, ionizing radiation during CT studies causes concern for patients who require dynamic observation, as well as for examination of children and young people. For this retrospective study, we included 15 suspected for COVID-19 patients who were hospitalized in April 2020, Russia. There were 4 adults with positive polymerase chain reaction (PCR) test for COVID-19. All patients underwent magnetic resonance imaging (MRI) examinations using MR-LUND PROTOCOL: Single-shot Fast Spin Echo (SSFSE), LAVA 3D and IDEAL 3D, Echo-planar imaging (EPI) diffusion-weighted imaging (DWI) and Fast Spin Echo (FSE) T2 weighted imaging (T2WI). On T2WI changes were identified in 9 (60,0%) patients, on DWI - in 5 (33,3%) patients. In 5 (33,3%) patients lesions of the parenchyma were visualized on T2WI and DWI simultaneously. At the same time, 4 (26.7%) patients had changes in lung tissue only on T2WI. (P(McNemar) = 0,125; OR = 0,00 (95%); kappa = 0,500). In those patients who had CT scan, the changes were comparable to MRI. The results showed that in case of CT is not available, it is advisable to conduct a chest MRI for patients with suspected or confirmed COVID-19. Considering that T2WI is a fluid-sensitive sequence, if imaging for the lung infiltration is required, we can recommend the abbreviated MRI protocol consisting of T2 and T1 WI. These data may be applicable for interpreting other studies, such as thoracic spine MRI, detecting signs of viral pneumonia of asymptomatic patients. MRI can detect features of viral pneumonia.

[Artificial intelligence for diagnosis of vertebral compression fractures using a morphometric analysis model, based on convolutional neural networks].

BACKGROUND: Pathological low-energy (LE) vertebral compression fractures (VFs) are common complications of osteoporosis and predictors of subsequent LE fractures. In 84% of cases, VFs are not reported on chest CT (CCT), which calls for the development of an artificial intelligence-based (AI) assistant that would help radiology specialists to improve the diagnosis of osteoporosis complications and prevent new LE fractures. AIMS: To develop an AI model for automated diagnosis of compression fractures of the thoracic spine based on chest CT images. MATERIALS AND METHODS: Between September 2019 and May 2020 the authors performed a retrospective sampling study of ССТ images. The 160 of results were selected and anonymized. The data was labeled by seven readers. Using the morphometric analysis, the investigators received the following metric data: ventral, medial and dorsal dimensions. This was followed by a semiquantitative assessment of VFs degree. The data was used to develop the Comprise-G AI mode based on CNN, which subsequently measured the size of the vertebral bodies and then calculates the compression degree. The model was evaluated with the ROC curve analysis and by calculating sensitivity and specificity values. RESULTS: Formed data consist of 160 patients (a training group - 100 patients; a test group - 60 patients). The total of 2,066 vertebrae was annotated. When detecting Grade 2 and 3 maximum VFs in patients the Comprise-G model demonstrated sensitivity - 90,7%, specificity - 90,7%, AUC ROC - 0.974 on the 5-FOLD cross-validation data of the training dataset; on the test data - sensitivity - 83,2%, specificity - 90,0%, AUC ROC - 0.956; in vertebrae demonstrated sensitivity - 91,5%, specificity - 95,2%, AUC ROC - 0.981 on the cross-validation data; for the test data sensitivity - 79,3%, specificity - 98,7%, AUC ROC - 0.978. CONCLUSIONS: The Comprise-G model demonstrated high diagnostic capabilities in detecting the VFs on CCT images and can be recommended for further validation.

[The future of computer-aided diagnostics in chest computed tomography]. / Perspektivy ispol'zovaniia kompleksnoi komp'iuter-assistirovannoi diagnostiki v otsenke struktur grudnoi kletki.

Recently, more and more attention has been paid to the utility of artificial intelligence in medicine. Radiology differs from other medical specialties with its high digitalization, so most software developers operationalize this area of medicine. The primary condition for machine learning is met because medical diagnostic images have high reproducibility. Today, the most common anatomic area for computed tomography is the thorax, particularly with the widespread lung cancer screening programs using low-dose computed tomography. In this regard, the amount of information that needs to be processed by a radiologist is snowballing. Thus, automatic image analysis will allow more studies to be interpreted. This review is aimed at highlighting the possibilities of machine learning in the chest computed tomography.

Effect of cell therapy on metabolite content in brain structures of children with consequences of severe brain injury: 1H magnetic resonance spectroscopy study.

The effect of intravenous injection of human umbilical cord blood cells on the levels of N-acetylaspartate, creatine and phosphocreatine, choline-containing compounds, glutamine and glutamate, and myoinositol in morphologically intact areas of the cortex, white matter, and hippocampus of children with consequences of traumatic brain injury was studied by single voxel 1H magnetic resonance spectroscopy. It was shown that cell therapy increases the content of N-acetylaspartate, a marker of functional integrity of neurons, in the white matter and in the cortex at the boundary between the frontotemporal and parietal lobes and reduces neurological deficit.

Calculation of the liquor system pliability using the mathematical simulation method.

Liquor circulation is a directed flow of the liquor from sites of its secretion to sites of resorption. This slow flow is modulated by pulsation caused by heart work. Phase-contrast magnetic resonance imaging is a method for noninvasive measurements of the linear velocity of these pulses in the cerebral aqueduct. A mathematical model reproducing pulsed flow of the liquor in the cerebral aqueduct is proposed and the procedure of evaluation of these parameters is presented. The pliability liquor system can be calculated from the values of liquor flow linear velocity in the cerebral aqueduct, measured by noninvasive method.

The use of hyperventilation in contrast-enhanced MR of brain tumors.

Angiographic studies have demonstrated improved visibility of glial tumors after hyperventilation. The present study was undertaken to determine whether hyperventilation would change the MR enhancement characteristics of various glial tumors. Eighteen patients were studied twice: once with standard contrast-enhanced MR imaging and again with standard imaging plus hyperventilation. After hyperventilation, six low-grade astrocytomas showed no change and three showed a small decrease in relative enhancement (<10%). The ependymomas showed a 10% to 13% increase in the degree of enhancement, but no change in the area of enhancement. All the anaplastic astrocytomas showed an increase in the degree of enhancement (mean, 38%). Three of the anaplastic astrocytomas showed new foci of enhancement that were not seen on the nonhyperventilation study. Hyperventilation appears to be an inexpensive and safe method for increasing the conspicuity of abnormal areas of the blood-brain barrier.

MRI of high-grade glial tumors: correlation between the degree of contrast enhancement and the volume of surrounding edema.

Contrast enhancement of malignant gliomas and the development of peritumoral edema are thought to be due to a breakdown of the blood-brain barrier (BBB). The degree to which these two factors are related to each other or to the degree of damage to the BBB is unknown. Our purpose was to quantitatively correlate the degree of enhancement with Gd-DTPA of anaplastic gliomas and glioblastoma multiforme with the volume of surrounding edema. In 14 patients, quantitative measurements of the volume of peritumoral edema and the degree of contrast enhancement were made. A high degree of correlation was found (r = 0.86, P < 0.01). These results can be viewed as indirect, radiological evidence that edema production is quantitatively related to the degree of breakdown of the BBB as determined by gadolinium enhancement. These results imply that the origin of the edema is in the area of breakdown of the BBB.