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ABSTRACT: PURPOSE: The aim of this study was to demonstrate the feasibility of cranial nerve (CN II-XII) imaging with 7 Tesla magnetic resonance imaging (MRI). METHODS: In this study four sequences were evaluated in three healthy volunteers using magnetization preparation rapid gradient echo (MPRAGE), constructive interference in steady state (CISS), true fast imaging with steady state precession (TrueFISP) and proton density (PD) T2-weighted turbo spin echo (TSE) sequences. RESULTS: It was found that MPRAGE did not always provide sufficient contrast to delineate in particular small CNs but displayed an overall good identification rate. The T2 sequence was not able to adequately differentiate the small CNs but showed a very good contrast between nerves and cerebrospinal fluid (CSF). As at lower magnetic fields steady state sequences displayed a high identification rate of all CNs in the axial plane but CISS suffered from susceptibility and pulsation artifacts, furthermore it was limited as no parallel imaging could be performed. The TrueFISP technique was reliable in identifying most CNs although suffering from banding artifacts. CONCLUSIONS: The TrueFISP sequence showed superior spatial resolution and contrast in comparison to the other sequences for imaging of CNs at 7 T.
Clinical neuroradiology. 09/2012;
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ABSTRACT: Background To assess effects of perceived treatment (i.e. drug vs placebo) on behavioral and neural responses to rectal pain stimuli delivered in a deceptive placebo condition. Methods This fMRI study analyzed the behavioral and neural responses during expectation-mediated placebo analgesia in a rectal pain model. In N = 36 healthy subjects, the blood oxygen level-dependent (BOLD) response during cued anticipation and painful stimulation was measured after participants were informed that they had a 50% chance of receiving either a potent analgesic drug or an inert substance (i.e., double-blind administration). In reality, all received placebo. We compared responses in subjects who retrospectively indicated that they received the drug and those who believed to have received placebo. Key Results 55.6% (N = 20) of subjects believed that they had received a placebo, whereas 36.1% (N = 13) believed that they had received a potent analgesic drug. Subjects who were uncertain (8.3%, N = 3) were excluded. Rectal pain-induced discomfort was significantly lower in the perceived drug treatment group (P < 0.05), along with significantly reduced activation of the insular, the posterior and anterior cingulate cortices during pain anticipation, and of the anterior cingulate cortex during pain (all P < 0.05 in regions-of-interest analyses). Conclusions & Inferences Perceived treatment constitutes an important aspect in placebo analgesia. A more refined understanding of individual treatment expectations and perceived treatment allocation has multiple implications for the design and interpretation of clinical trials and experimental studies on placebo and nocebo effects.
Neurogastroenterology and Motility 07/2012; 24(10):935-e462. · 3.41 Impact Factor
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ABSTRACT: Sequelae in children following cerebellar tumor removal surgery are well defined, and predictors for poor recovery include lesions of the cerebellar nuclei and the inferior vermis. Dynamic reorganization is thought to promote functional recovery in particular within the first year after surgery. Yet, the time course and mechanisms of recovery within this critical time frame are elusive and longitudinal studies are missing. Thus, a group of children and adolescents (n = 12, range 6-17 years) were followed longitudinally after cerebellar surgery and compared to age- and gender-matched controls (n = 11). Patients were examined (1) within the first days, (2) 3 months, and (3) 1 year after surgery. Each time behavioral tests of balance and upper limb motor function, ataxia rating, and a MRI scan were performed. Data were used for subsequent lesion-symptom mapping of cerebellar function. Behavioral improvements continued beyond 3 months, but were not complete in all patients after 1 year. At that time, remaining deficits were mild. Within the first 3 months, cerebellar lesion volumes were notably reduced by vanishing edema. Reduction in edema affecting the deep cerebellar nuclei but not reduction of total cerebellar lesion volume was a major predictor of early functional recovery. Persistent impairment in balance and upper limb function was linked to permanent lesions of the inferior vermis and the deep cerebellar nuclei.
The Cerebellum 05/2012; · 3.21 Impact Factor
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ABSTRACT: Functional magnetic resonance imaging (fMRI) studies are increasingly employed in different conscious states. Autogenic training (AT) is a common clinically used relaxation method. The purpose of this study was to investigate the cerebral modulation of pain activity patterns due to AT and to correlate the effects to the degree of experience with AT and strength of stimuli.
Thirteen volunteers familiar with AT were studied with fMRI during painful electrical stimulation in a block design alternating between resting state and electrical stimulation, both without AT and while employing the same paradigm when utilizing their AT abilities. The subjective rating of painful stimulation and success in modulation during AT was assessed.
During painful electrical stimulation without AT, fMRI revealed activation of midcingulate, right secondary sensory, right supplementary motor, and insular cortices, the right thalamus and left caudate nucleus. In contrast, utilizing AT only activation of left insular and supplementary motor cortices was revealed. The paired t-test revealed pain-related activation in the midcingulate, posterior cingulate and left anterior insular cortices for the condition without AT, and activation in the left ventrolateral prefrontal cortex under AT. Activation of the posterior cingulate cortex and thalamus correlated with the amplitude of electrical stimulation.
This study revealed an effect on cerebral pain processing while performing AT. This might represent the cerebral correlate of different painful stimulus processing by subjects who are trained in performing relaxation techniques. However, due to the absence of a control group, further studies are needed to confirm this theory.
European journal of pain (London, England) 03/2012; 16(9):1293-301. · 3.37 Impact Factor
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ABSTRACT: We assessed sex differences in behavioural and neural responses to rectal pain stimuli in healthy subjects.
In age- and body mass index-matched healthy subjects (n = 15 men, 15 women), rectal sensory and pain thresholds were assessed with a pressure-controlled barostat device. The blood oxygen level-dependent response during cued anticipation and painful stimulation was measured using functional magnetic resonance imaging (fMRI). Retrospective pain evaluations were accomplished with visual analogue scales. For fMRI data, region-of-interest (ROI) analyses and additional whole-brain analyses were carried out.
There were no sex differences in rectal thresholds or pain ratings. ROI analyses revealed comparable distension-induced activation of the thalamus, somatosensory cortex, insula and dorsolateral prefrontal cortex (DLPFC). Only in additional whole-brain analyses did we find increased activation in women in DLPFC and middle temporal gyrus during pain anticipation and in the cerebellum and medial frontal gyrus during pain. A significant inverse association between rectal pain threshold and distension-induced activation in virtually all ROIs was found in women. In men, pain thresholds and insula activation were positively correlated, as were pain ratings and anterior cingulate cortex activation.
Healthy men and women do not differ in behavioural measures of visceral pain sensitivity. The pattern of neural activation is comparable in the majority of pain-processing brain regions, although women may differ in the activation of DLPFC which could reflect sex differences in cognitive-emotional pain regulation. Women with lower pain thresholds showed greater neural responses, which may be relevant in the pathophysiology of visceral hyperalgesia.
European journal of pain (London, England) 12/2011; 16(3):349-58. · 3.37 Impact Factor
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ABSTRACT: There is increasing evidence of a topographic organization within the human cerebellar cortex for motor and non-motor functions. Likewise, a subdivision of the dentate nucleus in a more dorsal and rostral motor domain and a more ventral and caudal non-motor domain has been proposed by Dum and Strick (2003) based on anatomical studies in monkey. In humans, however, very little is known about topographic organization within the dentate nucleus. Activation of the dentate nucleus in a verb generation task was examined in young and healthy subjects using ultra-highfield 7T functional magnetic resonance imaging (fMRI) with its increase in signal-to-noise ratio. Data of 17 subjects were included in statistical analysis. Subjects were asked to (i) read words (nouns) aloud presented on a screen, (ii) silently read the same nouns, (iii) silently generate the appropriate verbs to the same nouns and (iv) to silently repeat the names of the months. A block design was used. For image processing, a recently developed region of interest (ROI) driven normalization method of the dentate nuclei was applied. Activation related to motor speech (contrast aloud reading minus silent reading) was strongest in the rostral parts of the dentate nucleus. Dorsorostral activations were present bilaterally. Activation related to verb generation (contrast verb generation minus silent reading) was found in the ventrocaudal parts of the dentate nucleus on the right. The present findings are in good accordance with the anatomical data in monkeys and suggest that the human dentate nucleus can be subdivided into a rostral and more dorsal motor domain and a ventrocaudal non-motor domain.
NeuroImage 05/2011; 57(3):1184-91. · 5.89 Impact Factor
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ABSTRACT: OBJECTIVE: Comparison of image quality in DE-CTA with and without automatic head bone removal (BR) versus CTA with 16-detectors as a tool in postoperative evaluation of patients after neurosurgical clipping. METHODS: In this study 30 aneurysms that had undergone neurosurgical clipping were included: 18 with DE-CTA and 12 with conventional CTA. The images were further processed using the volume rendering technique (VRT) and BR. Two experienced neuroradiologists reviewed the images regarding the severity of artefacts surrounding the clip, visibility of the vessels and remnant necks. The results were compared with DSA images, if performed. RESULTS: Significantly fewer disturbances by artefacts were observed in DE-CTA versus CTA in a 16-row system. Visibility of the surrounding vessels was satisfying in both techniques and there were comparable results with DSA with only one exception. All images produced with 140 kV provided fewer artefacts than those with 80 kV. CONCLUSION: DE-CTA provides better image quality with fewer disturbances by clip artefact, a satisfying evaluation of remnant aneurysm necks and the surrounding vessels. As this method is easily performed and readily accessible with fast image post-processing using BR it provides an opportunity to avoid invasive DSA in the evaluation of suspected aneurysm rests.
European Radiology 05/2011; · 3.22 Impact Factor
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ABSTRACT: Cranial dural arteriovenous fistulas are commonly treated using an endovascular method. In comparison to intracerebral arteriovenous malformations, it is important to reach the venous part of these malformations to maintain a complete occlusion. Therefore, often the venous side is totally occluded using coils and∕or glue.
We describe a patient with an initially Type IIab (Cognard classification) left occipital cranial fistula. The patient suffered from an intense pulsate tinnitus. Therefore, the first embolization was performed using an approach via the dilated left middle meningeal artery using Onyx. The shunt of the fistula was reduced significantly but total occlusion was impossible. Therefore, the venous approach was used. Over a guiding catheter in the sigmoid sinus, the venous side of the fistula could be reached with a microcatheter. This part of the fistula was then completely occluded using coated and bare coils, without occluding the adjacent sinus. Control angiography of all previous feeders showed a complete occlusion of the fistula (used classification: Cognard).
The fistula was entirely occluded. The patient's outcome was excellent. The patient did not develop any symptoms and no complication occurred due to the treatment.
Direct occlusion of the venous part of an arteriovenous cranial fistula can be an option before an occlusion of the sinus has to be performed. This approach can lead to reduction of risk during the endovascular procedure and risk reduction in long-term follow-up.
Journal of neurological surgery. Part A, Central European neurosurgery. 05/2011; 73(3):167-70.
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ABSTRACT: A new setting of intraoperative spinal angiography within an angiography suite is presented.
In a patient with thoracic arteriovenous malformation, the resection was performed within an angiography suite. Therefore a long sheath was applied, which remained sterile during the procedure and allowed a catheter to be introduced which is navigated into the noted segmental artery for contrast injection.
Digital subtraction angiography was performed prior to and after the resection at the AVM in order to visualize recent feeders and to ensure the complete occlusion.
This method leads to an increased image quality and a shorter operation time in comparison to an angiography within an operating room.
Central European neurosurgery 03/2011; 72(3):149-51. · 0.84 Impact Factor
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ABSTRACT: In this cross-sectional study we used magnetic resonance imaging (MRI)-based voxel based morphometry (VBM) in a sample of HIV positive patients to detect structural gray and white matter changes. Forty-eight HIV positive subjects with (n = 28) or without (n = 20) cognitive deficits (mean age 48.5 ± 9.6 years) and 48 age- and sex-matched HIV negative controls underwent MRI for VBM analyses. Clinical testing in HIV patients included the HIV dementia scale (HDS), Unified Parkinson's Disease Rating Scale (UPDRS) and the grooved pegboard test. Comparing controls with HIV positive patients with cognitive dysfunction (n = 28) VBM showed gray matter decrease in the anterior cingulate and temporal cortices along with white matter reduction in the midbrain region. These changes were more prominent with increasing cognitive decline, when assigning HIV patients to three cognitive groups (not impaired, mildly impaired, overtly impaired) based on performance in the HIV dementia scale. Regression analysis including all HIV positive patients with available data revealed that prefrontal gray matter atrophy in HIV was associated with longer disease duration (n = 48), while motor dysfunction (n = 48) was associated with basal ganglia gray matter atrophy. Lower CD4 cell count (n = 47) correlated with decrease of occipital gray matter. Our results provide evidence for atrophy of nigro-striatal and fronto-striatal circuits in HIV. This pattern of atrophy is consistent with motor dysfunction and dysexecutive syndrome found in HIV patients with HIV-associated neurocognitive disorder.
Journal of Neurology 01/2011; 258(6):1066-75. · 3.47 Impact Factor
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Neurology 12/2010; 75(23):2133. · 8.31 Impact Factor
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ABSTRACT: Dum and Strick (J. Neurophysiol. 2003; 89, 634-639) proposed a division of the cerebellar dentate nucleus into a "motor" and "non-motor" area based on anatomical data in the monkey. We asked the question whether motor and non-motor domains of the dentate can be found in humans using functional magnetic resonance imaging (fMRI). Therefore dentate activation was compared in motor and cognitive tasks. Young, healthy participants were tested in a 1.5 T MRI scanner. Data from 13 participants were included in the final analysis. A block design was used for the experimental conditions. Finger tapping of different complexities served as motor tasks, while cognitive testing included a verbal working memory and a visuospatial task. To further confirm motor-related dentate activation, a simple finger movement task was tested in a supplementary experiment using ultra-highfield (7 T) fMRI in 23 participants. For image processing, a recently developed region of interest (ROI) driven normalization method of the deep cerebellar nuclei was used. Dorso-rostral dentate nucleus activation was associated with motor function, whereas cognitive tasks led to prominent activation of the caudal nucleus. The visuospatial task evoked activity bilaterally in the caudal dentate nucleus, whereas verbal working memory led to activation predominantly in the right caudal dentate. These findings are consistent with Dum and Strick's anatomical findings in the monkey.
NeuroImage 11/2010; 54(4):2612-22. · 5.89 Impact Factor
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ABSTRACT: Approximately 6 - 50% of all ischemic strokes are caused by intracranial arterial stenosis (IAS). Despite medical prevention, patients with symptomatic IAS have a high annual risk for recurrent ischemic stroke of about 12%, and up to 19% in the case of high-grade IAS (≥ 70%). Digital subtraction angiography remains the gold standard for the diagnosis and grading of IAS. However, noninvasive imaging techniques including CT angiography, MR angiography, or transcranial Doppler and duplex ultrasound examinations are used in the clinical routine to provide additional information about the brain structure and hemodynamic. However, for technical reasons, the grading of stenoses is sometimes difficult and inaccurate. To date, aspirin is recommended as the treatment of choice in the prevention of recurrent ischemic stroke in patients with IAS. IAS patients who suffer a recurrent ischemic stroke or transient ischemic attack while taking aspirin can be treated with endovascular stenting or angioplasty in specialized centers. The periprocedural complication rate of these endovascular techniques is about 2 - 7% at experienced neuro-interventional centers. The rate of re-stenosis is reported between 10 and 40% depending on patient age and stenosis location. Further randomized studies comparing medical secondary prevention and endovascular therapy are currently being performed. With regard to the improvement of endovascular methods and lower complication rates, the indication for endovascular therapy in IAS could be broadened especially for stenosis in the posterior circulation.
RöFo - Fortschritte auf dem Gebiet der R 10/2010; 183(2):104-11. · 2.76 Impact Factor
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ABSTRACT: The deep cerebellar nuclei (DCN) are a key element of the cortico-cerebellar loop. Because of their small size and functional diversity, it is difficult to study them using magnetic resonance imaging (MRI). To overcome these difficulties, we present here three related methodological advances. First, we used susceptibility-weighted imaging (SWI) at a high-field strength (7T) to identify the dentate, globose, emboliform and fastigial nucleus in 23 human participants. Due to their high iron content, the DCN are visible as hypo-intensities. Secondly, we generated probabilistic maps of the deep cerebellar nuclei in MNI space using a number of common normalization techniques. These maps can serve as a guide to the average location of the DCN, and are integrated into an existing probabilistic atlas of the human cerebellum (Diedrichsen et al., 2009). The maps also quantify the variability of the anatomical location of the deep cerebellar nuclei after normalization. Our results indicate that existing normalization techniques do not provide satisfactory overlap to analyze the functional specialization within the DCN. We therefore thirdly propose a ROI-driven normalization technique that utilizes both information from a T1-weighted image and the hypo-intensity from a T2*-weighted or SWI image to ensure overlap of the nuclei. These techniques will promote the study of the functional specialization of subregions of the DCN using MRI.
NeuroImage 10/2010; 54(3):1786-94. · 5.89 Impact Factor
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ABSTRACT: Although up to 15% of patients with whiplash injury develop chronic headache, the basis and mechanisms of this posttraumatic headache are not well understood.
Thirty-two patients with posttraumatic headache following whiplash injury were investigated within 14 days after the accident and again after 3 months using magnetic resonance-based voxel-based morphometry. Twelve patients developed chronic headache lasting longer than 3 months and were studied a third time after 1 year.
Patients who developed chronic headache revealed decreases in gray matter in the anterior cingulate and dorsolateral prefrontal cortex after 3 months. These changes resolved after 1 year, in parallel to the cessation of headache. The same patients who developed chronic headache showed an increase of gray matter in antinociceptive brainstem centers, thalamus, and cerebellum 1 year after the accident.
We demonstrate adaptive gray matter changes of pain processing structures in patients with chronic posttraumatic headache in regard to neuronal plasticity, thus providing a biologically plausible basis for this common, disabling problem.
Neurology 09/2009; 73(12):978-83. · 8.31 Impact Factor
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ABSTRACT: The aim of the study was to analyse effects of psychological stress on the neural processing of visceral stimuli in healthy women. The brain functional magnetic resonance imaging blood oxygen level-dependent response to non-painful and painful rectal distensions was recorded from 14 healthy women during acute psychological stress and a control condition. Acute stress was induced with a modified public speaking stress paradigm. State anxiety was assessed with the State-Trait-Anxiety Inventory; chronic stress was measured with the Perceived Stress Questionnaire. During non-painful distensions, activation was observed in the right posterior insular cortex (IC) and right S1. Painful stimuli revealed activation of the bilateral anterior IC, right S1, and right pregenual anterior cingulate cortex. Chronic stress score was correlated with activation of the bilateral amygdala, right posterior IC (post-IC), left periaqueductal grey (PAG), and right dorsal posterior cingulate gyrus (dPCC) during non-painful stimulation, and with activation of the right post-IC, right PAG, left thalamus (THA), and right dPCC during painful distensions. During acute stress, state anxiety was significantly higher and the acute stress - control contrast revealed activation of the right dPCC, left THA and right S1 during painful stimulation. This is the first study to demonstrate effects of acute stress on cerebral activation patterns during visceral pain in healthy women. Together with our finding that chronic stress was correlated wit the neural response to visceral stimuli, these results provide a framework for further studies addressing the role of chronic stress and emotional disturbances in the pathophysiology of visceral hyperalgesia.
Neurogastroenterology and Motility 05/2009; 21(7):740-e45. · 3.41 Impact Factor
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ABSTRACT: Cerebellar ataxic gait is influenced greatly by balance disorders, most likely caused by lesions of the medial zone of the cerebellum. The contributions of the intermediate and lateral zone to the control of limb dynamics for gait and the adaptation of locomotor patterns are less well understood. In this study, we analysed locomotion and goal-directed leg movements in 12 patients with chronic focal lesions after resection of benign cerebellar tumours. The extent of the cortical lesion and possible involvement of the cerebellar nuclei was determined by 3D-MR imaging. The subjects (age range 13-39 years, mean 20.3; seven female; ICARS score: mean 5.7, SD 6.3) performed three tasks: goal-directed leg placement, walking and walking with additional weights on the shanks. Based on the performance on the first two tasks, patients were categorized as impaired or unimpaired for leg placement and for dynamic balance control in gait. The subgroup with impaired leg placement but not the subgroup with impaired balance showed abnormalities in the adaptation of locomotion to additional loads. A detailed analysis revealed specific abnormalities in the temporal aspects of intra-limb coordination for leg placement and adaptive locomotion. These findings indicate that common neural substrates could be responsible for intra-limb coordination in both tasks. Lesion-based MRI subtraction analysis revealed that the interposed and the adjacent dentate nuclei were more frequently affected in patients with impaired compared to unimpaired leg placement, whereas the fastigial nuclei (and to a lesser degree the interposed nuclei) were more frequently affected in patients with impaired compared with unimpaired dynamic balance control. The intermediate zone appears thus to be of particular importance for multi-joint limb control in both goal-directed leg movements and in locomotion. For locomotion, our results indicate an influence of the intermediate zone on dynamic balance control as well as on the adaptation to changes in limb dynamics.
Brain 11/2008; 131(Pt 11):2913-27. · 9.46 Impact Factor
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ABSTRACT: This study established the relationship between kinematic and grip force parameters in prehension tasks, disease severity and cerebellar atrophy in patients with cerebellar degeneration.
Prehension was tested in a condition during which the hand reached out, grasped, and lifted an object. Task complexity was modified by limiting the transport component to a single-joint movement, and introducing a bimanual condition.
Compared to controls the cerebellar patients showed disturbances in hand transport, in hand shaping and the most pronounced in time to peak grip force and the grip/load force coupling. Task-dependent changes did not differ between groups. Ataxia scores revealed significant correlations with hand transport and shaping measures only. Ataxia subscores correlated with volume reduction of appropriate longitudinal cerebellar zones. Volume reduction of the intermediate zone was associated with grip force coordination deficits.
Results indicate that the cerebellum may have a more general role in motor control of grasping independent of task complexity. Temporal and coordinative measures of grip force appear to be most useful to assess the severity of grasping deficits in patients with cerebellar degeneration not detectable by clinical ataxia scales.
To assess the severity and course of cerebellar disease grip force control in a standard prehension task is a sensitive quantitative measure.
Clinical Neurophysiology 11/2008; 119(11):2528-37. · 3.41 Impact Factor
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ABSTRACT: The human hippocampus plays a central role in various neuropsychiatric disorders, such as temporal lobe epilepsy (TLE), Alzheimer's dementia, mild cognitive impairment, and schizophrenia. Its volume, morphology, inner structure, and function are of scientific and clinical interest. Magnetic resonance (MR) imaging is a widely employed tool in neuroradiological workup regarding changes in brain anatomy, (sub-) volumes, and cerebral function including the hippocampus. Gain in intrinsic MR signal provided by higher field strength scanners and concomitant improvements in spatial resolution seem highly valuable. An examination protocol permitting complete, high-resolution imaging of the human hippocampus at 7 T was implemented. Coronal proton density, T2, T2*, and fluid-attenuated inversion recovery contrasts were acquired as well as an isotropic 3D magnetization-prepared rapid acquisition gradient-echo (500 microm isotropic voxel dimension, noninterpolated). Observance of energy deposition restrictions within acceptable scan times remained challenging in the acquisition of thin, spin-echo-based sections. At the higher resolution enabled by 7 T, demarcation of the hippocampus and some internal features including gray/white matter differentiation and depiction of the hippocampal mantle becomes much more viable when compared with 1.5 T; thus, in the future, this imaging technology might help in the diagnosis of subtle hippocampal changes.
Hippocampus 09/2008; 19(1):1-7. · 5.18 Impact Factor
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M Obermann,
O Yaldizli,
A de Greiff,
J Konczak,
M L Lachenmayer,
F Tumczak,
A R Buhl,
N Putzki,
J Vollmer-Haase, E R Gizewski,
H-C Diener,
M Maschke
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ABSTRACT: We tried to determine whether altered sensorimotor cortex and basal-ganglia activation in blepharospasm (BSP) and cervical dystonia (CD) are restricted to areas directly responsible for the innervation of dystonic muscles, or whether impairment in focal dystonia reaches beyond these direct associations supporting a more global disturbance of sensory and motor control in focal dystonia.
Twenty patients with focal dystonia (11 BSP, 9 CD) and 14 healthy controls were investigated with functional magnetic resonance imaging (fMRI) performing a simple grip force forearm contraction task.
BSP and CD patients and healthy controls showed similar activation in the pre-motor, primary motor and primary sensory cortex, whilst basal-ganglia activation was increased in BSP and CD with related activation patterns compared with controls. BSP patients had increased activation in the thalamus, caudate nucleus, putamen and lateral globus pallidus, whilst CD patients showed increased activation in the caudate nucleus, putamen and thalamus. No differences in applied grip force were detected between groups.
In both, BSP and CD, increased basal-ganglia activation could be demonstrated in a task not primarily involving the dystonic musculature affected by these disorders. Comparable activation changes may also indicate a common pathway in the pathophysiology in BSP and CD.
European Journal of Neurology 07/2008; 15(8):831-8. · 3.69 Impact Factor
