Brain neuroplasticity in multiple sclerosis patients in functional magnetic resonance imaging. Part 1: Comparison with healthy volunteers.

Purpose: The aim of this study was to assess the activity of motor cortical areas and the resting brain activity in a group of multiple sclerosis (MS) patients compared to a group of healthy individuals according to task-based functional magnetic resonance imaging (t-fMRI), resting state functional MRI (rs-fMRI), and volumetric MRI studies. Material and methods: The study enrolled 28 MS patients and 20 healthy volunteers who underwent MRI examinations. Primary motor cortex (M1), premotor area (PMA), supplementary motor area, as well as resting state networks (RSN's) and volumes of selected brain structures were subjected to a detailed analysis. Results: In MS patients, a motor task more often resulted in the activation of ipsilateral M1 cortex (observed in 39% of the studied group) as well as the PMA cortex (observed in 32% of MS patients). No differences in resting brain activity were found between the studied groups. Significant differences were observed in volumetric parameters of the total brain volume (healthy volunteers vs. MS patients, respectively): (1197 cm³ vs. 1150 cm³) and volumes of the grey matter (517 cm³ vs. 481 cm³), cerebellum (150 cm³ vs. 136 cm³), thalamus (16.3 cm³ vs. 12.6 cm³), putamen (8.9 cm³ vs. 7.7 cm³), and globus pallidus (4.57 cm³ vs. 3.57 cm³). Conclusions: In the MS patients, the motor task required significantly more frequent activation of the primary and secondary ipsilateral motor cortex compared to the group of healthy volunteers. The rs-fMRI study showed no differences in activity patterns within the RSN's. Differences in the total cerebral volume and the volume of the grey matter, cerebellum, thalamus, putamen, and globus pallidus were observed.

Brain neuroplasticity in multiple sclerosis patients in functional magnetic resonance imaging studies. Part 2: Effect of aerobic training.

Purpose: The aim of this study was to evaluate the effects of aerobic training on motor cortical areas in multiple sclerosis (MS) patients, based on task-based functional magnetic resonance imaging (t-fMRI) as well as on brain activity at rest, according to resting state functional MRI (rs-fMRI) studies. Material and methods: Multiple sclerosis patients were divided into 2 groups consisting of 14 participants each: the MS study group and the MS control group. All MS patients underwent clinical assessment and MRI examination, twice: in the MS study group at the time of inclusion in the study and after a 4-week period of aerobic training, whereas in the MS control group it happened at the time of inclusion and after a period of one month without exercise rehabilitation. The MRI study protocol included rs-fMRI and t-fMRI sequences, which were the grounds for an analysis of resting state networks (RSN) as well as peak level and cluster level parameters within motor cortex areas - the primary motor cortex, premotor area, and supplementary motor area, respectively. Results: In the MS study group, aerobic training improved the clinical condition and decreased the functional correlation between the sensorimotor network and the salience network. Also, significant decreases of the mean cluster level (72.42 vs. 38.35) and peak level values (10.89 vs. 7.64) were observed in the contralateral primary motor cortex in this group of patients between examinations. Conclusions: Aerobic training not only improves physical performance but also contributes to changes in brain activity - both within RSN and motor cortex areas in MS patients.

Magnetic resonance imaging assessment of cerebral small vessel disease intensification in patients with severe aortic valve stenosis.

PURPOSE: To assess the prevalence of the neuroradiological indices of cerebral small vessel disease (CSVD) in patients with severe aortic valve stenosis (AS) in magnetic resonance imaging (MRI). MATERIAL AND METHODS: 34 patients (age 60-90 years, 17 women and 17 men) with severe AS and 50 healthy controls (age 61-85 years, 29 women and 21 men) underwent MRI brain examinations, which were analysed for the neuroradiological indices of CSVD: hyperintensities in periventricular white matter (PVWM) and deep white matter (DWM), enlarged perivascular spaces (ePVS), lacunar strokes, and cerebral microbleeds (CMBs). RESULTS: PVWM hyperintensities were found in 46% of volunteers and was significantly lower (p = 0.027), corresponding to AS patients (80%), the density of lesions was higher in the AS group than in controls (p = 0.019). DWM hyperintensities were found more often in AS patients (76%) than in controls (66%) (p = 0.303), but the densities were similar in both groups. Lacunar strokes were found in 35% of AS patients and 16% of controls (p = 0.042). The average number of lacunar strokes per person was 0.9 in the AS group and 0.3 in the controls (p = 0.035). The AS group showed higher variance in the number of strokes: SD = 1.96 vs. SD = 1.06 in controls. Both prevalence and density of the ePVS and CMBs did not differ significantly between the groups. CONCLUSIONS: Neuroradiological indices of the vascular disease do not provide an unequivocal clue to the pathogenesis of CSVD in patients with severe AS. Most observations imply that CSVD is primarily a consequence of cerebral hypoperfusion caused by AS.

The use of functional magnetic resonance imaging techniques in the evaluation of patients with disorders of consciousness: a case report.

PURPOSE: The management of patients with disorders of consciousness (DOC) constitutes a challenge for clinicians. CASE REPORT: We present the case of a 66-year-old man who developed coma with subsequent DOC after a severe traumatic brain injury. Behavioural assessment constitutes the gold standard in the evaluation of patients with DOC. In the case presented herein the neuropsychological findings were ambiguous, and the patient underwent functional magnetic resonance imaging (fMRI) to determine whether he was in a vegetative state or minimally conscious state. Three paradigms: passive, active, and resting state fMRI were used to study the brain activity in our patient. CONCLUSIONS: fMRI provided reliable evidence of preserved minimal consciousness. The neuroimaging techniques used in our patient were vital for his further treatment.

Renal-aortic ratio as an objective measure of renal artery diameter a computed tomography angiography study.

BACKGROUND: Considering vital role of renal arteries in many surgical procedures, diameter of renal arteries seems to be an important measure of kidney perfusion. In this study, we analyzed a new parameter, renal-aortic ratio (R-Ar) as an objective measure of the renal artery diameter. METHOD: The study included CT angiographic images from 254 patients (129 women and 125 men). R-Ar was calculated by dividing the diameter of the main renal artery for each kidney by the aortic diameter. RESULTS: R-Ar values for the whole study group ranged between 0.0863 and 0.5083; the ranges of R-Ar values for women and men patients were 0.1150-0.5083 and 0.0863-0.4449, respectively. In 412 cases (81.10%), the kidney was supplied by a single renal artery (RA variant) and in 96 (18.90%) by more than one artery (sRA variant). A significant difference was found in R-Ar values for RA and sRA variants (p = 0.0008). When the anatomical variant of renal perfusion was not considered on statistical analysis, a significant difference was found between the R-Ar values for women and men (p = 0.0259). No statistically significant difference was observed in R-Ar values for the right and left kidneys (p = 0.3123). Spearman's coefficient of rank correlation between patient age and renal-aortic ratio values for the whole study group equaled - 0.36. CONCLUSION: The analysis of the renal-aortic ratio values demonstrated that the diameter of renal arteries depended primarily on their number, and the relative diameter of renal arteries in women was larger than in men.

Ischaemia of the medullary cone after stent-graft implantation in a patient with abdominal aortic aneurysm - a case study.

Preoperative visualization of the Adamkiewicz artery - the vessel which is to a great extent responsible for supplying blood to the medullary cone - is an important step which must be taken before initiating restorative procedures in the aorta. We present a case of a 67-year-old patient who underwent an intravascular stent-graft implantation procedure, due to clinical signs of abdominal aortic aneurysm. Routine pre-operative computed tomography examination failed to demonstrate the Adamkiewicz artery. On the second day after the surgery, as a result of unexpected clinical deterioration, an magnetic resonance imaging examination of the lumbar spine was carried out. Based on the magnetic resonance imaging images and clinical manifestations the diagnosis of ischaemia of the medullary cone was made. In our work we also present a deep analysis of the anatomy of small-sized vessels supplying blood to the spinal cord and discuss effective techniques which enable visualization of the Adamkiewicz artery.