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International audience; We proposed a novel method called HARP-I, which enhances the estimation of motion from tagged Magnetic Resonance Imaging (MRI). The harmonic phase of the images is unwrapped and treated as noisy measurements of reference coordinates on a deformed domain, obtaining motion with high accuracy using Radial Basis Functions interpolations. Results were compared against Shortest Path HARP Refinement (SP-HR) and Sine-wave Modeling (SinMod), two harmonic image-based techniques for motion estimation from tagged images. HARP-I showed a favorable similarity with both methods under noise-free conditions, whereas a more robust performance was found in the presence of noise. Cardiac strain was better estimated using HARP-I at almost any motion level, giving strain maps with less artifacts. Additionally, HARP-I showed better temporal consistency as a new method was developed to fix phase jumps between frames. In conclusion, HARP-I showed to be a robust method for the estimation of motion and strain under ideal and non-ideal conditions.

The aim of the present study was to observe visual pathway changes on the contralateral side in optic nerve sheath meningioma (ONSM). The authors present a case report of a 43-year-old patient with OfNSM on the right side. A complex ophthalmic examination was performed, including an assessment of visual functions, an electrophysiology examination and functional and structural MRI examinations. Visual acuity of the right eye after ONSM remained with no light perception, while that of the left side was normal. The visual field of the left eye was normal as was colour perception. An electrophysiology examination using a pattern electroretinogram revealed low amplitude values in the right eye. In the left eye, the finding was at the lower limit of normal results. The pattern visual evoked potential exhibited a bilateral lesion with a larger decrease in response after stimulation of the right eye. The structural MRI revealed intraorbital atrophy of the optic nerve on the right side throughout the whole course, which was accompanied by atrophy of the right half of the optic chiasm. Functional magnetic resonance imaging revealed zero activity after stimulation of the right eye and decreased activity in the visual centre after stimulation of the left eye. The present study demonstrated that unilateral damage to the optic nerve in ONSM is accompanied by significant changes on the contralateral side of the optic pathway.

Aims The purpose of the study was to evaluate the reliability of our new visual scale for a quick atrophy assessment of parietal lobes on brain Magnetic Resonance Imaging (MRI) among different professionals. A good agreement would justify its use for differential diagnosis of neurodegenerative dementias, especially early-onset Alzheimer’s Disease (AD), in clinical settings. Methods The visual scale named the Parietal Atrophy Score (PAS) is based on a semi-quantitative assessment ranging from 0 (no atrophy) to 2 (prominent atrophy) in three parietal structures (sulcus cingularis posterior, precuneus, parietal gyri) on T1-weighted MRI coronal slices through the whole parietal lobes. We used kappa statistics to evaluate intra-rater and inter-rater agreement among four raters who independently scored parietal atrophy using PAS. Rater 1 was a neuroanatomist (JM), rater 2 was an expert in MRI acquisition and analysis (II), rater 3 was a medical student (OP) and rater 4 was a neurologist (DS) who evaluated parietal atrophy twice in a 3-month interval to assess intra-rater agreement. All raters evaluated the same 50 parietal lobes on brain MRI of 25 cognitively normal individuals with even distribution across all atrophy degrees from none to prominent according to the neurologist’s rating. Results Intra-rater agreement was almost perfect with the kappa value of 0.90. Inter-rater agreement was moderate to substantial with kappa values ranging from 0.43-0.86. Conclusion The Parietal Atrophy Score is the reliable visual scale among raters of different professions for a quick evaluation of parietal lobes on brain MRI within 1-2 minutes. We believe it could be used as an adjunct measure in differential diagnosis of dementias, especially early-onset AD.

Purpose. The purpose of this study was to find out whether peeling of the epimacular membrane (EMM) and internal limiting membrane (ILM) for symptomatic lamellar macular hole (LMH), causes impairment of the visual cortex. Patients and Methods: This pilot study consisted of 8 eyes of 4 patients (2 females and 2 males), mean age 69.25 years (60-83 years), who underwent pars plana vitrectomy and EMM and ILM peeling in one eye for lamellar macular hole The second eye remained intact. The patients had no other ophthalmological or neurological disease. The control group consisted of 20 eyes of 10 healthy people (8 females and 2 males). mean age 52 years (34-65 years). In all of them, we performed functional magnetic resonance imaging (fMRI) of the brain to the visual paradigm (black and white chessboard of 25.8 x 16.2 degrees in size), as well as in patients 3-4 years following the surgery. For statistical processing, we used ANOVA and multiple regression for adjustment for the age of patients. Results: In all patients, we recorded a decrease in fMRI activity of the brain following stimulation of the eye in which surgical intervention was performed. The fMRI values using ANOVA (without adjustment for age) were significantly different between groups (P

The present study demonstrates alterations of the contralateral side optic tract to an optic nerve traumatic lesion. Visual acuity of the right eye following Traumatic optic neuropathy (TON) remained at 0 following the injury. Electrophysiological examination using pattern electroretinogram revealed values reduced by 50% in the right eye compared with the left eye. Pattern visual-evoked potential evaluation indicated a bilateral lesion with a higher decrease following right eye stimulation. Magnetic resonance imaging revealed right optic nerve atrophy. Functional magnetic resonance imaging indicated decreased activity of the visual centre during left eye stimulation. The present study revealed contralateral visual tract alterations following unilateral injury, and hypothesize that the ganglion cells of the retina respond initially to glial activation. These changes are, in our view, followed by changes in the visual pathway.

Background Aberrant amygdala reactivity to affective stimuli represents a candidate factor predisposing patients with bipolar disorder (BD) to relapse, but it is unclear to what extent amygdala reactivity is state-dependent. We evaluated the modulatory influence of mood on amygdala reactivity and functional connectivity in patients with remitted BD and healthy controls. Methods Amygdala response to sad versus neutral faces was investigated using fMRI during periods of normal and sad mood induced by autobiographical scripts. We assessed the functional connectivity of the amygdala to characterize the influence of mood state on the network responsible for the amygdala response. Results We included 20 patients with remitted BD and 20 controls in our study. The sad and normal mood exerted opposite effects on the amygdala response to emotional faces in patients compared with controls (F1,38 = 5.85, p = 0.020). Sad mood amplified the amygdala response to sad facial stimuli in controls but attenuated the amygdala response in patients. The groups differed in functional connectivity between the amygdala and the inferior prefrontal gyrus (p ≤ 0.05, family-wise error-corrected) of ventrolateral prefrontal cortex (vlPFC) corresponding to Brodmann area 47. The sad mood challenge increased connectivity during the period of processing sad faces in patients but decreased connectivity in controls. Limitations Limitations to our study included long-term medication use in the patient group and the fact that we mapped only depressive (not manic) reactivity. Conclusion Our results support the role of the amygdala-vlPFC as the system of dysfunctional contextual affective processing in patients with BD. Opposite amygdala reactivity unmasked by the mood challenge paradigm could represent a trait marker of altered mood regulation in patients with BD.

article Background: Left atrial (LA) fibrosis begets atrial fibrillation (AF). Cardiovascular magnetic resonance (CMR) using the late gadolinium enhancement (LGE) technique might visualize the LA fibrosis and thus help to choose an appropriate strategy for treatment of AF. In this regard, we investigated whether the extent of preablation LA LGE would predict AF recurrence after ablation in a non-selected patient population. Methods: CMR was performed in 95 patients before radiofrequency ablation of AF. An interpretable scan was available in 73 patients (age, 59 ± 8 years; men, 71%; persistent/paroxysmal AF, 55/45%). The extent of LA LGE was quantified by three established thresholding techniques. In addition, CMR was used to quantify LA volume and reservoir function. The patients were followed for AF recurrence for 1.3 ± 0.8 years. Results: The arrhythmia recurred in 29 (40%) of the patients. The extent of LA LGE did not differ between parox- ysmal and persistentAF and itdid not predict the AFrecurrence. Moreover, the extent of LA LGE did notcorrelate with LA volume, reservoir function and bipolar voltage. Conclusions: Our data indicate a limited value of a routine assessment of LA LGE before ablation of AF. Further ex- perimental and clinical researches should be done before applying the method to a wide clinical practice. © 2014 Elsevier Ireland Ltd. All rights reserved.

Background Diffusion-weighted magnetic resonance imaging (DW-MRI) is a widely used method for studying of asymptomatic brain injury during catheter ablation of atrial fibrillation (AF). However, this technique lacks sensitivity for subtle or diffuse brain lesions. We investigated whether detection of the ablation-related brain injury can improve by assessment of a biomarker of brain damage—protein S100B. Methods and Results DW-MRI and assessment of S100B were performed in 58 patients undergoing radiofrequency catheter ablation of paroxysmal or persistent AF 1 day before and after the procedure. We observed no symptomatic neurological complications. S100B levels increased after ablation above the upper reference limit of 105 ng/L in 3 patients. One of them developed a new ischemic lesion on the DW-MRI. No acute lesions emerged on DW-MRI in the patients with normal postablation S100B levels. Conclusion Serial assessment of serum protein S100B may improve detection of asymptomatic acute brain injury in patients undergoing radiofrequency catheter ablation of AF. In our study, the incidence of these events was 1.7% when evaluated only by DW-MRI, but the incidence increased to 5% after employing the more sensitive biomarker-based approach.

Objectives To map the brain activity during bladder filling by functional magnetic resonance imaging using a refined scanning protocol including synchronous urodynamics and pelvic floor muscle contractions. Methods A total of 23 healthy female volunteers (age 20–68 years) were enrolled. Participants were asked to contract their pelvic floor muscles. This was followed by a urodynamic examination consisting of repeated filling cycles. Brain activity was measured by functional magnetic resonance imaging using a 3T magnetic resonance system. Measurements of brain activity consisted of 120 functional scans during pelvic floor contractions and 210 scans during bladder filling. Each functional magnetic resonance imaging scan covered the brain with 35 slices. Statistical analyses used the general linear model and independent component analysis. Areas of activation were visualized using group statistics. Results The following main clusters of activation were observed during pelvic floor muscle contractions: medial surface of the frontal lobe (primary motor area), bilaterally; supplementary motor area, bilaterally; and left gyrus precentralis. During bladder filling, activation was detected in the inferior frontal lobe bordering the frontal cingulum, left gyrus parietalis superior, left central area, right insula, brainstem and thalamus with subcortical gray matter nuclei. Conclusions Our work extends an existing functional magnetic resonance imaging protocol for researching the neural control of the lower urinary tract. The present results are consistent with the available literature and agree with the present hypothetical functional model of lower urinary tract neural control.

Self-report studies indicate that cannabis could increase sexual desire in some users. We hypothesized that intoxication increases activation of brain areas responsive to visual erotica, which could be useful in the treatment of hypoactive sexual desire disorder, a condition marked by a lack of sexual desire. The aim of this study is to assess the aphrodisiacal properties of cannabis. We conducted an open-randomized study with 21 heterosexual casual cannabis users. A 3T MRI was used to measure brain activation in response to erotic pictures. Blood samples were collected to determine the serum levels of cannabinoids, cortisol and prolactin. Participants were grouped according to whether they had ever experienced any aphrodisiacal effects during intoxication (Group A) or not (Group non-A). Intoxication was found to significantly increase activation in the right nucleus accumbens in the Group A while significantly decreasing activation in the Group non-A. There was also a significant interaction between the group and intoxication, with elevated prolactin in the Group non-A during intoxication. No intoxication-related differences in subjective picture evaluations were found. Cannabis intoxication increases activation of the right nucleus accumbens to erotic stimuli. This effect is limited to users whose prolactin is not elevated in response to intoxication. This effect may be useful in the treatment of low sexual desire.

Whole-brain voxel-based morphometry (VBM) studies provide support for orbitofrontal, medial frontal as well as for dorsal cortical volumetric alteration in obsessive-compulsive disorder (OCD). However, there is still a need to replicate a priori unpredicted findings and to elucidate white matter volumetric abnormalities and relationships between grey (GM) and white (WM) matter volume and clinical characteristics of OCD. We compared GM and WM volume in a group of 14 patients with OCD and 15 healthy controls using a 3T MRI scanner and an optimized VBM protocol. Regression analysis was used to examine relationships between GM and WM volume and clinical variables. In OCD we have found total WM volume reduction and marked mediofrontal, right temporo-parieto-occipital, right precentral, left middle temporal, left cerebellar and bilateral pons and mesencephalon GM volume reduction in the voxel-based analysis (p

Very little is known about the accuracy of intravenous myocardial contrast echocadiography (MCE) in the detection of myocardial hibernation. There are also currently no data on the comparison of MCE to late gadolinium-enhanced magnetic resonance (LGE-MR) in this clinical setting. The aim of this pilot study was to predict recovery of regional function in patients with ischemic LV dysfunction undergoing bypass surgery and to compare the accuracy of MCE with LGE-MR in this clinical setting. The sensitivity of preserved myocardial perfusion during MCE for segmental function recovery (hibernating myocardium) of akinetic segments was 78% and was similar to LGE-MR (87%, p —NS). Specificity of MCE was higher than for LGE-CMR (72%, and 52%, respectively; p

AimPrevious studies have suggested altered structural and functional asymmetry of the brain in schizophrenia.MethodsFunctional MRI was used to assess differences in cortical activation during a verbal task in Broca's area and its contralateral homologue in four pairs of right-handed monozygotic (MZ) twins discordant and concordant for schizophrenia with low and high familial loading for the illness and four healthy control MZ twin pairs.ResultsPooled data from all subjects with schizophrenia showed increased activation in the right homologue of Broca's area in contrast to healthy individuals. Concordant twins (i.e. high familial loading group) showed prominent between co-twin differences in lateralization index within given region of interest. Intra-pair differences in lateralization index were significantly higher in concordant twins compared to the controls (0.69 ± 0.4 vs. 0.13 ± 0.13, P < 0.03), albeit no significant differences in the variable were shown between the discordant and control groups.ConclusionThis study provides evidence of reduced cerebral dominance for language processing in patients with schizophrenia. The findings further suggest the need for additional research on relative proportion of genetic and environmental factors underlying deviations of functional asymmetry in schizophrenia.

Aims To assess the accuracy of tissue Doppler imaging-derived myocardial positive pre-ejection velocity (+Vic) in detecting myocardial viability defined by dobutamine stress echocardiography (DSE), fluorine-18 fluorodeoxyglucose positron emission tomography (PET), and contrast-enhanced magnetic resonance imaging (MRI), and in predicting recovery of left ventricular (LV) function after coronary artery bypass grafting (CABG) in patients with chronic ischaemic LV dysfunction. Methods and results +Vic in dysfunctional segments was recorded in 54 patients treated medically and 65 patients undergoing CABG [age 67 ± 9 year; LV ejection fraction (EF) 30 ± 6%]. A good agreement was observed between +Vic and detection of viable myocardium at DSE, PET, and MRI (kappa = 0.76). The presence of +Vic in greater than or equal to five dysfunctional segments had the highest sensitivity (93%) and specificity (60%) to identify patients ( n = 28) with ≥10% increase in LV EF between baseline and 6-month echocardiogram. During follow-up (median 333 days, interquartile range 209–490 days), 13 cardiac events (6 deaths, 7 hospitalizations) occurred in 24 patients with small extent of viable myocardium (< 5 + Vic), whereas only four hospitalizations in 39 patients with ≥5 + Vic (54% vs. 10%; P < 0.001). Conclusion The extent of +Vic in dysfunctional segments accurately predicts extent of viable myocardium and bears a clinical prognostic value in patients with ischaemic LV dysfunction considered for CABG.

Background: The phenomenology of the clinical symptoms indicates that disturbance of the sense of self be a core marker of schizophrenia. Aims: To compare neural activity related to the self/other-agency judgment in patients with first-episode schizophrenia-spectrum disorders (FES, n = 35) and healthy controls (HC, n = 35). Method: A functional magnetic resonance imaging (fMRI) using motor task with temporal distortion of the visual feedback was employed. A task-related functional connectivity was analyzed with the use of independent component analysis (ICA). Results: (1) During self-agency experience, FES showed a deficit in cortical activation in medial frontal gyrus (BA 10) and posterior cingulate gyrus, (BA 31; P < .05, Family-Wise Error [FWE] corrected). (2) Pooled-sample task-related ICA revealed that the self/other-agency judgment was dependent upon anti-correlated default mode and central-executive networks (DMN/CEN) dynamic switching. This antagonistic mechanism was substantially impaired in FES during the task. Discussion: During self-agency experience, FES demonstrate deficit in engagement of cortical midline structures along with substantial attenuation of anti-correlated DMN/CEN activity underlying normal self/other-agency discriminative processes.

Patients with complete spinal cord injury (SCI) may maintain some perception of bladder fullness. The aim of the study was to evaluate brain activation arising from anticipated extraspinal sensory pathways.Fourteen patients ages 24-54 years were enrolled, all having experienced a complete SCI (ASIA A) at C7 to T5 an average of 17 months before study entry. Urodynamic equipment was used for repeated bladder filling and detrusor activity evaluation. All functional magnetic resonance imaging measurements were performed using a Siemens Trio 3T scanner with the GRE-EPI sequence (field of view = 192 × 192 mm, voxel 3 × 3 × 3 mm, TR/TE = 3000/30 ms, 45 slices). Nine hundred dynamic scans were acquired over 45 min. Statistical analysis was done in SPM8 using a general linear model. Statistics using t-tests were thresholded at P = 0.001.We excluded results from two patients because of activation artifacts. In 8 of 12 patients, significant brain activity was observed during urinary bladder filling. We found significant activation clusters at the nucleus of the solitary tract (NTS) (3/8), parabrachial nucleus (PBN) (4/8), hypothalamus (4/8), thalamus (6/8), amygdala (7/8), insular lobe (5/8), anterior cingulate gyrus (5/8), and prefrontal cortex (8/8). Activations in nuclei involved in afferents likely from the vagal nerve (NTS and PBN) correlated significantly with reported bladder sensations.These data suggest that extraspinal sensory pathways may develop following SCI and that vagal nerve may play a role in re-innervation of the urinary bladder. Neurourol. Urodynam. 36:155-159, 2017. © 2015 Wiley Periodicals, Inc.

The aim of the present study was to prospectively compare contrast-enhanced magnetic resonance imaging (CE-MRI) with single-photon emission tomography using (201)Thallium chloride (SPECT Tl) in the detection of myocardial viability. Patients with chronic coronary artery disease and systolic dysfunction defined by an ejection fraction (EF)

Introduction: Catheter ablation of atrial fibrillation (AF) requires exact anatomical information about pulmonary venous (PV) ostia. In this study, anatomy of pulmonary veins (PVs) was assessed using three-dimensional (3D) reconstructions of magnetic resonance angiography (MRA). Methods and Results: Contrast-enhanced MRA of the PVs was performed in 40 patients (mean age 53 ± 9 years) with paroxysmal (30 patients) or persistent (10 patients) AF, scheduled for circumferential ablation around PV ostia. PV ostial anatomy and diameters were evaluated from multiplanar reconstructions and compared with 3D reconstructions. Thirty (75%) patients presented with a common left-sided antrum (21 short and 9 long trunk), while additional PVs were found on right side in 23%. PV ostia were oblong in shape (mean diameters 17.0 ± 4.3 vs 10.5 ± 2.5 mm by two-dimensional (2D) measurements, and 20.8 ± 7.6 mm vs 12.9 ± 3.3 mm by 3D reconstruction, in long and short axis, respectively). There was a correlation between measurements obtained from 2D and 3D images, although 3D imaging provided slightly larger diameters. Conclusions: MRA with 3D reconstructions is an important technique for preprocedural assessment of PVs that allows full understanding of their anatomy and size. This information may be important for selection of appropriate tools.

To prospectively evaluate prevalence of neurovascular contacts (NVCs) at the rostral medulla oblongata in normotensive and hypertensive subjects.Forty-three patients with severe essential hypertension and 45 normotensive subjects were matched for age, sex, and body mass index. Magnetic resonance (MR) imaging included transverse and coronal T2-weighted turbo spin-echo (section thickness, 3.0 mm), transverse three-dimensional (3D) time-of-flight MR angiographic (section thickness, 0.8 mm), and 3D constructive interference in steady state (CISS) (section thickness, 1.0 mm) sequences. All MR images were reviewed by two radiologists who were blinded to the hypertensive status of subjects. Presence and degree of NVC at rostral medulla and left/right rostral ventrolateral medulla (RVLM) were evaluated together with conspicuity of anatomic structures on MR images. Differences in prevalence of NVC among normotensive and hypertensive subjects were tested for statistical significance (P.05) by using nonparametric tests.Among hypertensive patients, 34 (79%) of 43 showed NVC of rostral medulla at any location, and 14 (33%) of 43 had NVC at the left RVLM. In controls (normotensive subjects), 35 (78%) of 45 showed NVC of rostral medulla, and 17 (38%) of 45 had NVC at left RVLM. Prevalence of NVC was not significantly different between both groups at any location of rostral medulla. Compared with T2-weighted turbo spin-echo and 3D time-of-flight MR imaging sequences, 3D CISS offered better contrast resolution of neural and vascular structures and superior delineation of outer vascular contours.Vascular compression of the rostral medulla oblongata is a frequent finding in both hypertensive and normotensive subjects. Results of this study do not support NVC at left RVLM as an etiologic factor in essential hypertension.

Objective: This paper presents functional magnetic resonance imaging (fMRI) and magnetic resonance spectroscopy (MRS) findings in a monozygotic twin pair discordant for schizophrenia. Method: Functional magnetic resonance imaging was used to determine hemispheric lateralization for speech and proton MRS (1H-MRS) was employed to assess the extent of putative insult to anterior hippocampus. Results: Despite concordant right handedness, subject with schizophrenia displayed bilateral activation in areas subserving speech with greater extent of the total activated area compared with the healthy twin. The affected twin displayed relative bilateral decrease in N-acetylaspartate/creatin concentration in the anterior hippocampus compared with the healthy one. Conclusion: This is an evidence for non-genetic impairment of cerebral lateralization in monozygotic twin with schizophrenia.

The authors report a case of binasal hemianopia in a 34-year-old female who, at the age of 22 years, underwent resection of a pinealoma located at the 3rd ventricle. Less than a year after the surgery, partial visual field losses occurred. Examination of retina, retinal nerve fiber layer (RNFL) as well as examination of the ganglion cell complex (GCC) excluded a pregeniculate lesion. Functional magnetic resonance imaging (fMRI) responses evoked by both bi- and monocular stimulation confirmed our finding of reduced activity in the visual cortex corresponding to the damage in a portion of the visual pathway.

There is still little scientific evidence for the efficacy of neurofacilitation approaches and their possible influence on brain plasticity and adaptability. In this study, the outcome of a new kind of neurofacilitation approach, motor programme activating therapy (MPAT), was evaluated on the basis of a set of clinical functions and with MRI. Eighteen patients were examined four times with standardized clinical tests and diffusion tensor imaging to monitor changes without therapy, immediately after therapy and 1 month after therapy. Moreover, the strength of effective connectivity was analysed before and after therapy. Patients underwent a 1-h session of MPAT twice a week for 2 months. The data were analysed by nonparametric tests of association and were subsequently statistically evaluated. The therapy led to significant improvement in clinical functions, significant increment of fractional anisotropy and significant decrement of mean diffusivity, and decrement of effective connectivity at supplementary motor areas was observed immediately after the therapy. Changes in clinical functions and diffusion tensor images persisted 1 month after completing the programme. No statistically significant changes in clinical functions and no differences in MRI-diffusion tensor images were observed without physiotherapy. Positive immediate and long-term effects of MPAT on clinical and brain functions, as well as brain microstructure, were confirmed.

Purpose: Phenylketonuria (PKU) patients were examined by different MR techniques to explain the pathological changes observed in periventricular white brain matter using conventional MR imaging. Material and Methods: Fifteen patients with treated classical PKU were examined by 1H spectroscopy, relaxometry and diffusion imaging on a whole-body 1.5-T MR imager. Results: Known PKU lesions characterized by T2 enhancement in periventricular white matter were observed in all patients. The MR spectra from the lesioned areas showed a significant decrease in choline concentration. The mean ADC of water decreased and tortuosity increased in PKU lesions compared to control data. Conclusion: The results support the following hypothesis: The T2 increase in the PKU lesion reflects a raised concentration of free water molecules (about 15%) that have an increased trajectory between collisions compared to the same region in controls. The increase in water mobility might be explained by changes in extracellular space volume and myelin sheaths, which, presumably, have a different geometry with more hydrophobic sites in PKU patients. The changes result in increased tortuosity and may be confirmed by the loss of anisotropy in PKU lesions.

Diffusion-weighted magnetic resonance imaging (DW-MRI) is a widely used method for studying of asymptomatic brain injury during catheter ablation of atrial fibrillation (AF). However, this technique lacks sensitivity for subtle or diffuse brain lesions. We investigated whether detection of the ablation-related brain injury can improve by assessment of a biomarker of brain damage-protein S100B.DW-MRI and assessment of S100B were performed in 58 patients undergoing radiofrequency catheter ablation of paroxysmal or persistent AF 1 day before and after the procedure. We observed no symptomatic neurological complications. S100B levels increased after ablation above the upper reference limit of 105 ng/L in 3 patients. One of them developed a new ischemic lesion on the DW-MRI. No acute lesions emerged on DW-MRI in the patients with normal postablation S100B levels.Serial assessment of serum protein S100B may improve detection of asymptomatic acute brain injury in patients undergoing radiofrequency catheter ablation of AF. In our study, the incidence of these events was 1.7% when evaluated only by DW-MRI, but the incidence increased to 5% after employing the more sensitive biomarker-based approach.

To map the brain activity during bladder filling by functional magnetic resonance imaging using a refined scanning protocol including synchronous urodynamics and pelvic floor muscle contractions.A total of 23 healthy female volunteers (age 20-68 years) were enrolled. Participants were asked to contract their pelvic floor muscles. This was followed by a urodynamic examination consisting of repeated filling cycles. Brain activity was measured by functional magnetic resonance imaging using a 3T magnetic resonance system. Measurements of brain activity consisted of 120 functional scans during pelvic floor contractions and 210 scans during bladder filling. Each functional magnetic resonance imaging scan covered the brain with 35 slices. Statistical analyses used the general linear model and independent component analysis. Areas of activation were visualized using group statistics.The following main clusters of activation were observed during pelvic floor muscle contractions: medial surface of the frontal lobe (primary motor area), bilaterally; supplementary motor area, bilaterally; and left gyrus precentralis. During bladder filling, activation was detected in the inferior frontal lobe bordering the frontal cingulum, left gyrus parietalis superior, left central area, right insula, brainstem and thalamus with subcortical gray matter nuclei.Our work extends an existing functional magnetic resonance imaging protocol for researching the neural control of the lower urinary tract. The present results are consistent with the available literature and agree with the present hypothetical functional model of lower urinary tract neural control.

As recently demonstrated, spin saturation effects in 3D time-of-flight (TOF) MR angiography (MRA) can be reduced by using RF pulses with linearly increasing flip angles (ramp pulses) in the main direction of flow. We developed a model for calculating the signal distribution of proton flow within the excitation volume (slab) for different ramp slopes and compared the results with the measured distribution for the lower-leg arteries. The ramp pulses were generated using the Fourier transformation of the desired excitation profiles. With a bandwidth of 6 kHz and a pulse length of 2.56 ms satisfactory ramps with variable slopes were generated and applied in a standard flow-compensated 3D FISP sequence. The effects on the signal distribution in the resulting angiograms of the lower limbs revealed a considerable reduction of saturation losses in agreement with the calculations. Calculated optimal ramp slopes are provided for flow velocities ranging from 5 to 50 cm/s and excitation volumes ranging from 5 to 25 cm.

We mapped brain activity during micturition using functional magnetic resonance imaging with simultaneous recording of urodynamic properties during slow bladder filling and micturition.We evaluated 12 healthy female volunteers 20 to 68 years old. Eight subjects could urinate while supine. Meaningful data were obtained on 6 of these subjects. Brain activity was recorded continuously during bladder filling and micturition. Functional magnetic resonance imaging measurements made during the micturition phase were used for the final analysis.Using group statistics we identified clusters of brain activity in the parahippocampal gyrus, anterior cingulate gyrus, inferior temporal gyrus and inferior frontal gyrus during micturition. At the individual level we also observed activation in the upper pontine region, thalamus and posterior cingulum. In subjects unable to void brain activation was documented in the frontal lobe and posterior cingulate gyrus but not in the pons, thalamus or anterior cingulate gyrus. In 5 subjects we identified a relevant pattern of brain activity during the terminal portion of the filling phase when the patient reported a strong desire to urinate.This new protocol allows for the localization of brain structures that are active during micturition. Data suggest that additional validation studies are needed. Future studies will test modifications that include more detailed monitoring of bladder sensation, stratifying subjects based on age and gender, and increasing the number of data points by adding subjects and the number of micturitions recorded in a single subject.

Objectives. To address the role of latent T. gondii infection in schizophrenia we studied the infl uence of latent toxoplasmosis on brain morphology. Methods. An optimized voxel-based morphometry of magnetic resonance imaging was analyzed by analysis of variance with diagnosis and seropositivity as factors in 44 schizophrenic patients (12 T. gondii positive) and 56 controls (13 T. gondii positive). Results. Grey matter (GM) volume was reduced in schizophrenia patients compared with controls in the cortical regions, hippocampus and in the caudate. In the schizophrenia sample we found a signifi cant reduction of GM volume in T. gondii positive comparing with T. gondii -negative patients bilaterally in the caudate, median cingulate, thalamus and occipital cortex and in the left cerebellar hemispheres. T. gondii -positive and -negative controls did not differ in any cluster. Among participants seropositive to T. gondii the reduction of GM in the schizophrenia subjects was located in the same regions when comparing the entire sample (11,660 over-threshold voxels ( P 0.05, FWR corrected). The differences between T. gondii -negative patients and controls consisted only of 289 voxels in temporal regions. Conclusions. Our study is the fi rst to document that latent toxoplasmosis reduces GM in schizophrenia but not in controls.

Functional MRI was used to evaluate factors influencing hemispheric dominance for language in 34 children suffering from intractable focal epilepsy due to left hemispheric lesion of pre- (n = 19) or postnatal (n = 15) origin. Nineteen children (56%) exhibited pronounced left-hemispheric language dominance. Significant co-activation of the right hemisphere or a complete language shift to this hemisphere was present in 15 children (44%). Atypical language representation was detected in 6 children (31,6%) with developmental pathology and in 9 patients (60%) with acquired epileptogenic lesion. Younger age at epilepsy onset and longer duration of epilepsy correlated significantly with atypical language presentation (p0,017 and p0,025). Whereas lesser tendency of prenatal lesions to displace cortical language centers did not reach statistical significance in simple paired tests, multiple logistic regression analysis viewed positive interaction between language shift, etiology and age at epilepsy onset. In conclusion, the language network reorganization was strongly influenced by both, the age at epilepsy onset and duration of epilepsy, and to a lesser degree by the character of the epileptogenic lesion, either developmental or acquired postnatally.

The aim of the present study was to prospectively compare contrast-enhanced magnetic resonance imaging (CE-MRI) with single-photon emission tomography using (201)Thallium chloride (SPECT Tl) in the detection of myocardial viability. Patients with chronic coronary artery disease and systolic dysfunction defined by an ejection fraction (EF)or= 45% were included. CE-MRI was performed 10-15 minutes after the administration of a gadolinium-based contrast agent using an Inversion Recovery Turbo FLASH (fast low-angle shot) sequence. A 4-hour rest redistribution protocol was used for SPECT Tl. Radionuclide ventriculography was used for the assessment of EF. Forty patients with an EF of 33.1 +/- 7.7% were included. Thirty-two underwent a follow-up examination after revascularization. Comparison of viability assessment was performed in 1360 segments. Agreement was noted in 1065 (78.3%) segments, resulting in a kappa value of 0.336. Discrepancies were observed in 96 SPECT Tl viable segments that were described as nonviable according to CE-MRI and in 199 SPECT Tl nonviable segments that were viable in the CE-MRI study. In patients undergoing the follow-up examination, EF increased by 5.5 +/- 7.3% (33.6 +/- 8.6% to 39.2 +/- 9.7%), but the relation between the amount of dysfunctional viable myocardium defined by both methods studied and the change in EF after revascularization was very weak and not statistically significant. Moderate agreement in the myocardial viability assessment between CE-MRI and SPECT Tl was observed. CE-MRI seems to be more accurate in identifying myocardial viability in inferior and inferolateral segments. We were unable to verify if either of the methods studied is useful for the prediction of EF improvement after revascularization.

Purpose of this study was to assess different aspects of ophthalmic radiosurgery accuracy performed on the Leksell Gamma Knife (ELEKTA Instrument, Sweden): (1) accuracy of magnetic resonance imaging

Ultrafast T2-weighted (T2-W) MRI sequences are currently considered a routine technique for fetal MR imaging. Limited experience exists with fetal T1-weighted (T1-W) imaging techniques. To determine MRI patterns of some fetal abdominal or haemorrhagic disorders with particular respect to the diagnostic value of T1-W images. In addition to standard T2-W single-shot sequences, T1-W single-shot and/or multislice sequences were employed in 25 MR examinations performed in 23 fetuses between 20 and 36 weeks of gestation for more detailed assessment of liver, meconium-filled digestive tract, haemorrhage, or further characterization of a fetal abdominal mass. Diagnostic value and presence of motion artefacts on T1-W images was recorded in each case. T1-W images enabled superior delineation of fetal liver and large intestine. They provided additional diagnostic information in 9 (39%) of 23 fetuses. One false-positive and one false-negative MRI diagnosis of malrotation anomaly were encountered. Use of single-shot T1-W sequences reduced the occurrence of motion artefacts in 64%. Our results suggest that the specific signal properties of methaemoglobin, meconium and liver are sufficiently important for T1-W sequences to become a routine part of fetal MRI protocols when dealing with digestive tract anomalies, diaphragmatic and abdominal wall defects, intraabdominal masses, and fetal haemorrhage.

In MRI applications where short acquisition time is necessary, the increase of acquisition speed is often at the expense of image resolution and SNR. In such cases, the newly developed parallel acquisition techniques could provide images without mentioned limitations and in reasonably shortened measurement time. A newly designed eight-channel head coil array (i-PAT coil) allowing for parallel acquisition of independently reconstructed images (GRAPPA mode) has been tested for its applicability in neuroradiology. Image homogeneity was tested in standard phantom and healthy volunteers. BOLD signal changes were studied in a group of six volunteers using finger tapping stimulation. Phantom studies revealed an important drop of signal even after the use of a normalization filter in the center of the image and an important increase of artifact power with reduction of measurement time strongly depending on the combination of acceleration parameters. The additional application of a parallel acquisition technique such as GRAPPA decreases measurement time in the range of about 30%, but further reduction is often possible only at the expense of SNR. This technique performs best in conditions in which imaging speed is important, such as CE MRA, but time resolution still does not allow the acquisition of angiograms separating the arterial and venous phase. Significantly larger areas of BOLD activation were found using the i-PAT coil compared to the standard head coil. Being an eight-channel surface coil array, peripheral cortical structures profit from high SNR as high-resolution imaging of small cortical dysplasias and functional activation of cortical areas imaged by BOLD contrast. In BOLD contrast imaging, susceptibility artifacts are reduced, but only if an appropriate combination of acceleration parameters is used.

If corpus callosum (CC) mediates the activation of the secondary somatosensory area (SII) ipsilateral to the side of stimulation, then the peak latencies of the contra- and ipsilateral SII activity as well as the amplitude of the ipsilateral SII activity should correlate with the size of CC. Innocuous electrical stimuli of five different intensities were applied to the ventral surface of the right index finger in 15 right-handed men. EEG was recorded using 82 closely spaced electrodes. The size of CC and of seven callosal regions was measured from the mid-sagittal slice of a high-resolution anatomical MRI. The activation in the contralateral and ipsilateral SII was evaluated using spatio-temporal source analysis. At the strongest stimulus intensity, the size of the intermediate part of the callosal truncus correlated negatively with the interpeak latency of the sources in ipsi- and contralateral SII (r = -0.83, P0.01). Stepwise regression analysis showed that the large size of the intermediate truncus of CC was paralleled by a latency reduction of peak activity of the ipsilateral SII, whereas both contra- and ipsilateral peak latencies were positively correlated. The peak amplitude of the ipsilateral SII source correlated positively with the size of the intermediate truncus of CC, and with the peak amplitudes of sources in the primary somatosensory cortex (SI) and in the mesial frontal cortex. The results suggest that in right-handed neurologically normal men, the size of the intermediate callosal truncus contributes to the timing and amplitude of ipsilateral SII source activity.

There have recently been a number of studies dealing with the absolute quantification of concentrations of MR-visible phosphorus compounds in different tissues. The use of absolute values rather than intensity ratios may furnish additional information about metabolic changes associated with different diseases. The purpose of this study was to develop a general procedure for measuring molar metabolite concentrations and to apply it with respect to the evaluation of human liver 31P-MRS data measured using a standard slice-selective two-dimensional CSI sequence and commercial1H/31P surface coil. The experimental determination of all surface coil-related factors influencing signal intensity was undertaken using a gradient echo imaging technique that can be adapted to commercial systems. The resulting values for healthy volunteers (N = 9) showed concentrations of PME = 2.8 ± 1.3 mM, PDE = 9.9 ± 2.7 mM,P i = 1.7 ± 0.7 mM, and ATP = 3.6 + 0.9 mM in the human liver. The data are quite consistent with published findings.

This report describes a rare case of anomalous systemic and pulmonary venous return that was surgically corrected. It consisted of left inferior vena cava with hemiazygous continuation into the persistent left superior vena cava, partial anomalous pulmonary venous return from the right lung and sinus venosus atrial septal defect.

ObjectiveMyocardial viability and left ventricular dyssynchrony are important predictors of long-term outcomes in patients with ischemic left ventricular dysfunction. The objective of this study was to test the hypothesis that assessment of myocardial viability and left ventricular dyssynchrony will predict perioperative mortality in high-risk patients with ischemic left ventricular dysfunction having coronary artery bypass surgery.MethodsThe study consisted of 79 consecutive patients with ischemic cardiomyopathy (age 65 ± 9 years; 81% men; ejection fraction 30% ± 6%) and logistic European system for cardiac operative risk evaluation > 10% having coronary artery bypass surgery. Myocardial viability was assessed by delayed contrast-enhanced magnetic resonance imaging. Left ventricular dyssynchrony was calculated using tissue Doppler from measurements of regional electromechanical coupling times in left ventricular basal segments before coronary artery bypass surgery.ResultsTwenty (25.3%) patients died within 30 days following coronary artery bypass surgery. Survivors (n = 59) showed a larger extent of viable myocardium (6.9 ± 3.6 viable segments vs 3.4 ± 3.3 viable segments, P < .001) and smaller left ventricular dyssynchrony (75 ± 5 ms vs 179 ± 83 ms, P < .001) than nonsurvivors. The presence of significant dyssynchrony (≥105 ms) and absence of myocardial viability (