Multiple sclerosis with megacystic presentation: A case report.

Multiple sclerosis is a frequent condition where the diagnosis relies on clinical presentation, neurologic examination, cerebro spinal fluid markers, and diagnostic imaging tests; however, atypical variants of the disease can lead to misdiagnosis in some scenarios. Herein, we describe a case of a 24-year-old patient with multiple sclerosis with megacystic plaques, in which appropriate interpretation of the imaging findings lead to a proper diagnosis and treatment.

Altered brain creatine cycle metabolites in bipolar I disorder with childhood abuse: A 1H magnetic resonance spectroscopy study.

BACKGROUND: Childhood abuse (CA) is a risk factor for a number of psychiatric disorders and has been associated with higher risk of developing bipolar disorders (BD). CA in BD has been associated with more severe clinical outcomes, but the neurobiological explanation for this is unknown. Few studies have explored in vivo measurement of brain metabolites using proton magnetic resonance spectroscopy (1H-MRS) in CA and no studies have investigated the association of CA severity with brain neurometabolites in BD. OBJECTIVE: To investigate whether CA severity is associated with changes in anterior cingulate cortex (ACC) neurometabolite profile in BD and HC subjects. METHODS: Fifty-nine BD I euthymic patients and fifty-nine HC subjects were assessed using the Childhood Trauma Questionnaire (CTQ) and underwent a 3-Tesla 1H-MRS scan. Severity of childhood abuse (physical, sexual and emotional) and its association with levels of brain metabolites was analyzed within each group. RESULTS: BD patients had higher total scores on the CTQ and higher severity rates of sexual and physical abuse compared to HC subjects. Greater severity of physical and sexual abuse was associated with increased ACC PCr level and lower Cr/PCr ratio in the BD group only. CONCLUSION: Sexual and physical abuse in BD patients, but not in HC subjects, appeared to be associated with creatine metabolism in the ACC, which can influence neuronal mitochondrial energy production. Further studies should investigate whether this is the mechanism underlying the association between CA and worse clinical outcomes in BD.

Investigation of NAA and NAAG dynamics underlying visual stimulation using MEGA-PRESS in a functional MRS experiment.

N-acetyl-aspartate (NAA) is responsible for the majority of the most prominent peak in (1)H-MR spectra, and has been used as diagnostic marker for several pathologies. However, ~10% of this peak can be attributed to N-acetyl-aspartyl-glutamate (NAAG), a neuropeptide whose release may be triggered by intense neuronal activation. Separate measurement of NAA and NAAG using MRS is difficult due to large superposition of their spectra. Specifically, in functional MRS (fMRS) experiments, most work has evaluated the sum NAA+NAAG, which does not appear to change during experiments. The aim of this work was to design and perform an fMRS experiment using visual stimulation and a spectral editing sequence, MEGA-PRESS, to further evaluate the individual dynamics of NAA and NAAG during brain activation. The functional paradigm used consisted of three blocks, starting with a rest (baseline) block of 320 s, followed by a stimulus block (640 s) and a rest block (640 s). Twenty healthy subjects participated in this study. On average, subjects followed a pattern of NAA decrease and NAAG increase during stimulation, with a tendency to return to basal levels at the end of the paradigm, with a peak NAA decrease of -(21±19)% and a peak NAAG increase of (64±62)% (Wilcoxon test, p<0.05). These results may relate to: 1) the only known NAAG synthesis pathway is from NAA and glutamate; 2) a relationship between NAAG and the BOLD response.