Proton magnetic resonance spectroscopy (1H-MRS) of the brain in patients with tick-borne encephalitis

Meta-analysis and open-source database for in vivo brain Magnetic Resonance spectroscopy in health and disease

Proton (1H) Magnetic Resonance Spectroscopy (MRS) is a non-invasive tool capable of quantifying brain metabolite concentrations in vivo. Prioritization of standardization and accessibility in the field has led to the development of universal pulse sequences, methodological consensus recommendations, and the development of open-source analysis software packages. One on-going challenge is methodological validation with ground-truth data. As ground-truths are rarely available for in vivo measurements, data simulations have become an important tool. The diverse literature of metabolite measurements has made it challenging to define ranges to be used within simulations. Especially for the development of deep learning and machine learning algorithms, simulations must be able to produce accurate spectra capturing all the nuances of in vivo data. Therefore, we sought to determine the physiological ranges and relaxation rates of brain metabolites which can be used both in data simulations and as reference estimates. Using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, we've identified relevant MRS research articles and created an open-source database containing methods, results, and other article information as a resource. Using this database, expectation values and ranges for metabolite concentrations and T2 relaxation times are established based upon a meta-analyses of healthy and diseased brains.

COVID-19’s effects on the Egyptian population’s brain: Could MRI and specialized MR spectroscopic analysis be beneficial?

Background

The recent pandemic of COVID‐19 has thrown the world into chaos due to its high rate of transmissions. Recently viewed neurological manifestations among hospitalized Egyptian patients with COVID‐19 in quarantine centres. Ataxia, disturbed consciousness and convulsions should be further evaluated by MRI and MRS for CNS involvement by SARS‐CoV‐2. How COVID-19 targeting the CNS is still under study, as it is difficult to predict which diagnostic neurological tests will be used to identify high-risk COVID19 patients. MR spectroscopy represents a non-invasive in vivo diagnostic technique for evaluation of metabolic profile of the brain and can reveal important information about the underlying pathologies. Multiple recent reports in the medical literature had confirmed the neurological complications in COVID-19 infection, though few studies has reported the MR spectroscopic findings in these patients. This cross-sectional study aimed to use MRI and MR spectroscopic findings for evaluation of the neurological manifestation of Egyptian COVID‐19 patients.

Results

Ninety-one male and twenty-seven female met the inclusion criteria, with a mean age of 52 years ± 10 (SD) (age range; 12–78 years). The commonest neurological manifestations were disturbed conscious level (82.2%). The most common MRI findings were acute ischemic insult with/without haemorrhagic areas (42.3%), demyelinating patches of altered signal intensity (31.3%). Sixty cases who had haemorrhagic areas were excluded to perform MRS due to contamination of the spectra by blood component. However, the remaining 67 patients had NAA reduction, choline elevation, glutamate/glutamine and lactate elevation in short TE35, with mean of NAA/Cr ratio = 1.04 ± 0.14, Choline/Cr = 0.49 ± 0.04 and Glx/Cr = 1.56 ± 0.22.

Conclusions

During the current pandemic of COVID-19, radiologists should be aware of wide spectrum of MRI and MRS findings of COVID-19-related CNS involvement.