Iron Concentration in Deep Gray Matter Structures is Associated with Worse Visual Memory Performance in Healthy Young Adults.

Abnormally high deposition of iron can contribute to neurodegenerative disorders with cognitive impairment. Since previous studies investigating cognition-brain iron accumulation relationships focused on elderly people, our aim was to explore the association between iron concentration in subcortical nuclei and two types of memory performances in a healthy young population. Gender difference was found only in the globus pallidus. Our results showed that iron load characterized by R2* value on the MRI in the caudate and putamen was related to visual memory, while verbal memory was unrelated to iron concentration.

Changes of migraine-related white matter hyperintensities after 3 years: a longitudinal MRI study.

OBJECTIVE/BACKGROUND: The aim of this longitudinal study was to investigate changes of migraine-related brain white matter hyperintensities 3 years after an initial study. Baseline quantitative magnetic resonance imaging (MRI) studies of migraine patients with hemispheric white matter hyperintensities performed in 2009 demonstrated signs of tissue damage within the hyperintensities. The hyperintensities appeared most frequently in the deep white matter of the frontal lobe with a similar average hyperintensity size in all hemispheric lobes. Since in this patient group the repeated migraine attacks were the only known risk factors for the development of white matter hyperintensities, the remeasurements of migraineurs after a 3-year long follow-up may show changes in the status of these structural abnormalities as the effects of the repeated headaches. METHODS: The same patient group was reinvestigated in 2012 using the same MRI scanner and acquisition protocol. MR measurements were performed on a 3.0-Tesla clinical MRI scanner. Beyond the routine T1-, T2-weighted, and fluid-attenuated inversion recovery imaging, diffusion and perfusion-weighted imaging, proton magnetic resonance spectroscopy, and T1 and T2 relaxation time measurements were also performed. Findings of the baseline and follow-up studies were compared with each other. RESULTS: The follow-up proton magnetic resonance spectroscopy studies of white matter hyperintensities showed significantly decreased N-acetyl-aspartate (median values 8.133 vs 7.153 mmol/L, P=.009) and creatine/phosphocreatine (median values 4.970 vs 4.641 mmol/L, P=.015) concentrations compared to the baseline, indicating a more severe axonal loss and glial hypocellularity with decreased intracellular energy production. The diffusion values, the T1 and T2 relaxation times, and the cerebral blood flow and volume measurements presented only mild changes between the studies. The number (median values 21 vs 25, P<.001) and volume (median values 0.896 vs 1.140 mL, P<.001) of hyperintensities were significantly higher in the follow-up study. No changes were found in the hemispheric and lobar distribution of hyperintensities. An increase in the hyperintensity size of preexisting lesions was much more common than a decrease (median values 14 vs 5, P=.004). A higher number of newly developed hyperintensities were detected than disappeared ones (130 vs 22), and most of them were small (<.034 mL). Small white matter hyperintensities in patients with a low migraine attack frequency had a higher chance to disappear than large white matter hyperintensities or white matter hyperintensities in patients with a high attack frequency (coefficient: -0.517, P=.034). CONCLUSIONS: This longitudinal MRI study found clinically silent brain white matter hyperintensities to be predominantly progressive in nature. The absence of a control group precludes definitive conclusions about the nature of these changes or if their degree is beyond normal aging.

[Functional MRI investigation of brain activity triggered by taste stimulation]. / Ízstimulációval kiváltott agyi tevékenység funkcionális MR-vizsgálata elhízásban.

INTRODUCTION: Many factors contribute to the pathogenesis of morbid obesity, and the central nervous system - as one of those - also has an important role. Numerous studies focus on the central regulation of eating and metabolism, since associated problems like obesity, anorexia, diabetes or metabolic syndrome put an increasing burden on the health system of modern societies. Neither the pathophysiologic changes, nor the normal regulation of these systems are known adequately. Functional MR (fMRI) imaging, which has certainly gained popularity recently, aims to better understand these mechanisms. In this series we studied the brain fMRI activity changes of normal and obese persons, triggered by gustatory stimulation. METHODS: 10 obese and 10 normal weight healthy volunteers took part in the study, with comparable age and sex distribution. Gustatory stimulation was performed by 0.1 M sucrose (pleasant), 0.5 mM quinine HCl (unpleasant) and complex vanilla flavored (Nutridrink) solutions, which were administered through 0.5 mm PVC tubes, in 5-5 ml portions. For rinsing distilled water with neutral flavor was used. Imaging was performed in a 3T MRI, applying standard EPI sequences. Post processing of data was accomplished by FSL software package. RESULTS: Brain activation for gustatory stimuli was characteristically different between the two groups. There were high intensity activations in more cortical and subcortical regions of the obese volunteers compared to the normal ones. CONCLUSIONS: Our current fMRI investigations revealed different activations of numerous brain regions of normal and obese individuals, triggered by pleasant and unpleasant gustatory stimulation. Based on these results this method can help to recognize the role of the central nervous system in obesity, and may contribute to develop new therapies for weight loss.

Coffee consumption may influence hippocampal volume in young women.

Caffeine is the most often used psychoactive substance. Caffeine may influence neuroplasticity in animals. We investigated the relationship between caffeine intake (coffee consumption) and brain morphology. Forty-five healthy, non-smoking women aged 19-30 were included in the present study. We used semi-automatic user-independent MR volumetry and voxel-based morphometry. We investigated the relationship between caffeine intake (coffee consumption) and the volumes of the cortical brain structures where caffeine is supposed to act. We found that high-level and low-level caffeine intake was associated with a larger hippocampus compared to moderate-level caffeine intake. The other brain structures showed no association with coffee consumption or caffeine intake. The U-shape association between caffeine concentration and its effect has already been described in some experimental studies. To our knowledge this is one of the very first studies, which tries to find an association between brain morphology and coffee consumption or caffeine intake in humans using MR imaging.

Attack-related brainstem activation in a patient with SUNCT syndrome: an ictal fMRI study.

The authors report functional magnetic resonance imaging (fMRI) study data of a 60-year-old patient having short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) syndrome. Three consecutive pain attacks were detected during the imaging session and strong brainstem activation was found. It was concluded that the brainstem can be involved in the pain signal transmission in SUNCT syndrome.

In vitro evaluation of alternative oral contrast agents for MRI of the gastrointestinal tract.

PURPOSE: In vitro evaluation of different materials as potential alternative oral contrast agents for small bowel MRI. MATERIALS AND METHODS: The T1 and T2 relaxation times of rose hip syrup, black currant extract, cocoa, iron-deferoxamine solution and a commonly used oral contrast material (1 mM Gd-DTPA) were determined in vitro at different concentrations on a 1.0 T clinical MR scanner. T1 values were obtained with an inversion prepared spoiled gradient echo sequence. T2 values were obtained using multiple echo sequences. Finally the materials were visualized on T1-, T2- and T2*-weighted MR images. RESULTS: The relaxation times of the undiluted rose hip syrup (T1=110+/-5 ms, T2=86+/-3 ms), black currant extract (T1=55+/-3 ms, T2=39+/-2 ms) and 5 mM iron-deferoxamine solution (T1=104+/-4 ms, T2=87+/-2 ms) were much shorter than for a 1mM Gd-DTPA solution (T1=180+/-8 ms, T2=168+/-5 ms). Dilution of black currant extract to 30% or a 3 mM iron-deferoxamine solution conducted to T1 relaxation times which are quite comparable to a 1 mM Gd-DTPA solution. Despite its much lower metal content an aqueous cocoa suspension (100 g/L) produced T2 relaxation times (T1=360+/-21 ms, T2=81+/-3 ms) more or less in the same range like the 5 mM iron-deferoxamine solution. Imaging of our in vitro model using clinical sequences allowed to anticipate the T1-, T2- and T2*-depiction of all used substances. Cocoa differed from all other materials with its low to moderate signal intensity on T1- and T2-weighted sequences. While all substances presented a linear 1/T1 and 1/T2 relationship towards concentration, rose hip syrup broke ranks with a disproportionately high increase of relaxation at higher concentrations. CONCLUSIONS: Rose hip syrup, black currant extract and iron-deferoxamine solution due to their positive T1 enhancement characteristics and drinkability appear to be valuable oral contrast agents for T1-weighted small bowel MRI. Cocoa with its differing relaxation and signal enhancement properties is a promising oral contrast agent but needs further clinical evaluation.