Decreased Distance between Representation Sites of Distinct Facial Movements in Facial Synkinesis-A Task fMRI Study.

This study aimed to investigate the cortical functional alterations in patients with unilateral facial synkinesis using the task-designed functional magnetic resonance imaging. Fourteen unilateral synkinesis followed by peripheral facial nerve palsy patients and eighteen healthy adults were recruited in this study. Four facial motor tasks, i.e. left/right blinking and left/right smiling, were performed by each subject during the scans. Based on the activation maps, the spatial distance between the representation sites in the contralateral pre-/post-central gyrus of left or right blinking and smiling tasks (i.e. left/right B-S-distance) were calculated. Patients with unilateral facial synkinesis showed decreased B-S-distances during blinking and smiling tasks on the affected half face (9.68 ±â€¯3.92 mm) compared to both average distances in healthy controls (14.95 ±â€¯5.55 mm; p = 0.002) and unaffected half face tasks in patients (16.19 ±â€¯7.87 mm; p = 0.011). These findings demonstrated cortical reorganization in facial synkinesis and suggested a conceivable mechanism corresponding to the simultaneous facial movement. This potentially provides a new modulation target for preventive, therapeutic and rehabilitative maneuver of this disease.

The plasticity of the corticospinal tract in children with obstetric brachial plexus palsy after Botulinum Toxin A treatment.

Botulinum neurotoxin A (BTX-A) intervention has long-term benefits for children with obstetric brachial plexus palsy (OBPP). Although cortical plasticity has been widely studied, plasticity in white matter has not received as much attention. Here, six children with OBPP underwent functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) before and 6 months after BTX-A treatment. Surface electromyography (EMG) was recorded. The aim was to investigate changes in the corticospinal tract (CST) as an example longitudinal observation of white matter plasticity. Deterministic fiber tracking with a Fiber Assignment by Continuous Tracking algorithm was used to reconstruct the CST. Fiber tracts passing through a region of interest (ROI) in the posterior limb of the internal capsule and a target ROI in the upper-limb representation of M1 (defined by task-related fMRI) were selected as the CST. Motor performances were improved while EMG showed no significant difference 6 months after the treatment. We observed a significant increase in mean fractional anisotropy and a significant decrease in fiber number after treatment. We analyzed the correlations between DTI metrics and clinical motor assessments. Although the correlation results were not statistically significant, they support the notion that BTX-A treatment causes white matter plasticity and has a positive long-term outcome. Peripheral deafferentation may lead to altered information flow, resulting in the positive adaptation of white matter. This study provides novel insight into cerebral plasticity following peripheral nerve regeneration and indicates that a combination of relatively non-invasive therapies can accelerate plasticity of sensorimotor circuits and promote functional recovery in OBPP.

Patterns of cortical reorganization in facial synkinesis: a task functional magnetic resonance imaging study.

Facial synkinesis, a sequela of peripheral facial nerve palsy, is characterized by simultaneous involuntary facial movement during a voluntary desired one. Maladaptive cortical plasticity might be involved in the dysfunction of facial muscles. This cohort study investigated the cortical functional alterations in patients with unilateral facial synkinesis, using the task functional magnetic resonance imaging. Facial motor tasks, including blinking and smiling, were performed by 16 patients (aged 30.6 ± 4.5 years, 14 females/2 males) and 24 age- and sex-matched healthy controls (aged 29.1 ± 4.2 years, 19 females/5 males). Results demonstrated that activation in the cortico-facial motor representation area was lower during tasks in patients with facial synkinesis compared with healthy controls. Facial movements on either side performed by patients caused more intensive activation of the supplementary motor area on the contralateral side of the affected face, than those on the unaffected side. Our results revealed that there was cortical reorganization in the primary sensorimotor area and the supplementary motor area. This study was registered in Chinese Clinical Trial Registry (registration number: ChiCTR1800014630).

Small-worldness of brain networks after brachial plexus injury: A resting-state functional magnetic resonance imaging study.

Research on brain function after brachial plexus injury focuses on local cortical functional reorganization, and few studies have focused on brain networks after brachial plexus injury. Changes in brain networks may help understanding of brain plasticity at the global level. We hypothesized that topology of the global cerebral resting-state functional network changes after unilateral brachial plexus injury. Thus, in this cross-sectional study, we recruited eight male patients with unilateral brachial plexus injury (right handedness, mean age of 27.9 ± 5.4 years old) and eight male healthy controls (right handedness, mean age of 28.6 ± 3.2). After acquiring and preprocessing resting-state magnetic resonance imaging data, the cerebrum was divided into 90 regions and Pearson's correlation coefficient calculated between regions. These correlation matrices were then converted into a binary matrix with affixed sparsity values of 0.1-0.46. Under sparsity conditions, both groups satisfied this small-world property. The clustering coefficient was markedly lower, while average shortest path remarkably higher in patients compared with healthy controls. These findings confirm that cerebral functional networks in patients still show small-world characteristics, which are highly effective in information transmission in the brain, as well as normal controls. Alternatively, varied small-worldness suggests that capacity of information transmission and integration in different brain regions in brachial plexus injury patients is damaged.

Clinical features and mutation spectrum in Chinese patients with CADASIL: A multicenter retrospective study.

AIM: To characterize clinical features and mutation spectrum in Chinese patients with CADASIL. METHODS: We collected 261 clinically suspected Chinese CADASIL patients from three hospitals located in different regions of China. Sanger sequencing is performed to screen the exons 2 to 24 of NOTCH3 gene. Clinical and genetic data were retrospectively studied. Haplotype analyses were performed in patients carrying p.Arg544Cys and p.Arg607Cys, respectively. RESULTS: A total of 214 patients were finally genetically diagnosed as CADASIL, with 45 known NOTCH3 mutations and a novel c.1817G>T mutation. We found that patients carrying p.Arg607Cys or p.Arg544Cys mutation located in exon 11 occupied nearly 35% in our mutation spectrum. In retrospectively study of clinical data, we found a higher number of patients having cognitive impairment and a lower number of patients having migraine with aura. Furthermore, we identified that patients carrying mutations in exon 11 seemed to experience a later disease onset (p=6.8×10-5 ). Additionally, a common haplotype was found in patients from eastern China carrying p.Arg607Cys, and the patients from Fujian carrying p.Arg544Cys shared the same haplotype with patients from Taiwan carrying p.Arg544Cys. CONCLUSIONS: These findings broaden the mutational and clinical spectrum of CADASIL and provide additional evidences for the existence of founder effect in CADASIL patients.

Supplementary motor area deactivation impacts the recovery of hand function from severe peripheral nerve injury.

Although some patients have successful peripheral nerve regeneration, a poor recovery of hand function often occurs after peripheral nerve injury. It is believed that the capability of brain plasticity is crucial for the recovery of hand function. The supplementary motor area may play a key role in brain remodeling after peripheral nerve injury. In this study, we explored the activation mode of the supplementary motor area during a motor imagery task. We investigated the plasticity of the central nervous system after brachial plexus injury, using the motor imagery task. Results from functional magnetic resonance imaging showed that after brachial plexus injury, the motor imagery task for the affected limbs of the patients triggered no obvious activation of bilateral supplementary motor areas. This result indicates that it is difficult to excite the supplementary motor areas of brachial plexus injury patients during a motor imagery task, thereby impacting brain remodeling. Deactivation of the supplementary motor area is likely to be a serious problem for brachial plexus injury patients in terms of preparing, initiating and executing certain movements, which may be partly responsible for the unsatisfactory clinical recovery of hand function.

Computed tomography and magnetic resonance features of intracranial hemangioendothelioma: A study of 7 cases.

The current study aimed to present the neuroradiological and histopathological features of intracranial hemangioendothelioma (HE). The computed tomography (CT; n=3) and magnetic resonance imaging (MRI; n=7) features, and the clinical presentations of 7 patients with pathologically documented HEs were retrospectively analyzed. Lesions were observed in the right side of the skull (the frontal bone in 1 patient and the parietal bone in 1 patient), the tentorium (2 patients), the cerebral falx (1 patient), the right cavernous sinus (1 patient) and the right temporal lobe (1 patient). The tumor was lobulated in 5 cases and round in 2 cases. The majority of tumors appeared isointense or hypointense with multiple scattered hyperintensities on T1-weighted MRI. Moreover, the lesions appeared as inhomogeneous hyperintense regions with multiple enlarged and tortuous blood flow voids on T2-weighted MRI. The lesions also showed marked gadolinium enhancement in a honeycomb pattern. CT scan results showed a isoattenuation region (32-47 HU), with numerous small, round, high-density foci. The 2 cases with skull lesions presented with local bone destruction and discontinuous bone lines of the tabula interna ossis cranii. In 1 case, MR angiography revealed abnormal vessels in the basilar region. A total of 4 cases were epithelial HE, 2 were retiform HE and 1 was kaposiform HE. Histological examination revealed endothelial cell proliferation with vascular lesions and a mucous matrix or dense fibrous mesenchyme. In conclusion, intracranial HE is rare, but should be considered in the differential diagnosis when evaluating intracranial neoplasms. A well-defined lobulated mass and imaging features that include internal heterogeneity, small scattered hemorrhages and thromboses, signal voids of vessels, and marked and delayed enhancement may confirm the diagnosis of HE.

Brain functional network abnormality extends beyond the sensorimotor network in brachial plexus injury patients.

Brachial plexus injury (BPI) is a type of severe peripheral nerve trauma that leads to central remodeling in the brain, as revealed by functional MRI analysis. However, previously reported remodeling is mostly restricted to sensorimotor areas of the brain. Whether this disturbance in the sensorimotor network leads to larger-scale functional remodeling remains unknown. We sought to explore the higher-level brain functional abnormality pattern of BPI patients from a large-scale network function connectivity dimension in 15 right-handed BPI patients. Resting-state functional MRI data were collected and analyzed using independent component analysis methods. Five components of interest were recognized and compared between patients and healthy subjects. Patients showed significantly altered brain local functional activities in the bilateral fronto-parietal network (FPN), sensorimotor network (SMN), and executive-control network (ECN) compared with healthy subjects. Moreover, functional connectivity between SMN and ECN were significantly less in patients compared with healthy subjects, and connectivity strength between ECN and SMN was negatively correlated with patients' residual function of the affected limb. Functional connectivity between SMN and right FPN were also significantly less than in controls, although connectivity between ECN and default mode network (DMN) was greater than in controls. These data suggested that brain functional disturbance in BPI patients extends beyond the sensorimotor network and cascades serial remodeling in the brain, which significantly correlates with residual hand function of the paralyzed limb. Furthermore, functional remodeling in these higher-level functional networks may lead to cognitive alterations in complex tasks.

Hepatic sarcoidosis mimicking liver cancer.

We present a case of a 50-year-old woman with multiple occupations in the liver. Liver cancer was strongly suspected initially according to the results of imaging examination. However, sarcoidosis was confirmed subsequently by liver biopsy, so methylprednisolone was then prescribed and the patient showed favorable therapeutic response. This case report suggests that hepatic mass in Chinese patients without any history of hepatitis virus infection should be carefully investigated before giving a diagnosis of liver cancer. The report also reminds us that the clinical presentation of sarcoidosis is complex and involvement of a single extra-pulmonary organ should not be ignored.

Differences in Brain Adaptive Functional Reorganization in Right and Left Total Brachial Plexus Injury Patients.

OBJECTIVE: Total brachial plexus avulsion injury (BPAI) results in the total functional loss of the affected limb and induces extensive brain functional reorganization. However, because the dominant hand is responsible for more cognitive-related tasks, injuries on this side induce more adaptive changes in brain function. In this article, we explored the differences in brain functional reorganization after injuries in unilateral BPAI patients. METHODS: We applied resting-state functional magnetic resonance imaging scanning to 10 left and 10 right BPAI patients and 20 healthy control subjects. The amplitude of low-frequency fluctuation (ALFF), which is a resting-state index, was calculated for all patients as an indication of the functional activity level of the brain. Two-sample t-tests were performed between left BPAI patients and controls, right BPAI patients and controls, and between left and right BPAI patients. RESULTS: Two-sample t-tests of the ALFF values revealed that right BPAIs induced larger scale brain reorganization than did left BPAIs. Both left and right BPAIs elicited a decreased ALFF value in the right precuneus (P < 0.05, Alphasim corrected). In addition, right BPAI patients exhibited increased ALFF values in a greater number of brain regions than left BPAI patients, including the inferior temporal gyrus, lingual gyrus, calcarine sulcus, and fusiform gyrus. CONCLUSION: Our results revealed that right BPAIs induced greater extents of brain functional reorganization than left BPAIs, which reflected the relatively more extensive adaptive process that followed injuries of the dominant hand.

Long-term ongoing cortical remodeling after contralateral C-7 nerve transfer.

OBJECT: Contralateral C-7 nerve transfer was developed for the treatment of patients with brachial plexus avulsion injury (BPAI). In the surgical procedure the affected recipient nerve is connected to the ipsilateral motor cortex, and the dramatic peripheral alteration may trigger extensive cortical reorganization. However, little is known about the long-term results after such specific nerve transfers. The purpose of this study was to investigate the long-term cortical adaptive plasticity after BPAI and contralateral C-7 nerve transfer. METHODS: In this study, 9 healthy male volunteers and 5 male patients who suffered from right-sided BPAI and had undergone contralateral C-7-transfer more than 5 years earlier were included. Functional MRI studies were used for the investigation of long-term cerebral plasticity. RESULTS: The neuroimaging results suggested that the ongoing cortical remodeling process after contralateral C-7 nerve transfer could last for a long period; at least for 5 years. The motor control of the reinnervated limb may finally transfer from the ipsilateral to the contralateral hemisphere exclusively, instead of the bilateral neural network activation. CONCLUSIONS: The authors believe that the cortical remodeling may last for a long period after peripheral rearrangement and that the successful cortical transfer is the foundation of the independent motor recovery.

MRI features in children with desmoplastic medulloblastoma.

Desmoplastic medulloblastoma (DMB) is a variant that has a more favorable prognosis compared to classical medulloblastoma, but its MRI features have not been as well described. We retrospectively reviewed the MRI features in children with pathologically proven DMB, including T2-weighted, fluid-attenuated inversion recovery (FLAIR) and contrast enhanced images, with isotropic diffusion-weighted (DW) MRI also performed in some patients. There were 16 tumors in 12 patients; one patient had five discrete lesions. In all patients, the tumor involved the cerebellar vermis, with nine lesions showing multiple peripheral small cysts. In nine of 16 tumors, there were focal areas of isointensity or hypointensity on T2-weighted or FLAIR images; seven of these showed corresponding focal enhancement. There was also one patient with radiating star-shaped enhancement in two lesions, and a multi-nodular enhancing pattern was observed in another patient. Low apparent diffusion coefficient (ADC) values were found in the lesions studied by DW MRI in five patients. DMB may have a typical imaging appearance of peripheral cysts, decreased ADC and focal enhancing areas corresponding to focal isointense or hypointense signal on T2-weighted and FLAIR images. Although these MRI features may distinguish this variant of medulloblastoma, multinodular or star-shaped radiating enhancement may also be detected in some patients.

CT volume measurement for prognostic evaluation of unresectable hepatocellular carcinoma after TACE.

AIM: To analyze the value of computed tomography (CT) volume measurements for evaluation of the survival rate of unresectable hepatocellular carcinoma (HCC) patients after transcatheter arterial chemoembolization (TACE). METHODS: One hundred and sixty-six unresectable HCC patients after TACE were involved in this retrospective study. Hepatic CT scan was performed for all patients before and 4 wk to 2 mo after TACE to define the morphologic features of HCC including its largest diameter, volume, product of the greatest axial dimension, tumor to liver volume ratio (TTLVR), and tumor shrinkage ratio. Clinical variables used in the study included gender, age, pattern of tumor growth, number of lesions, Child-Pugh classification of liver function, repeated TACE times, pre- or post-treatment alpha-fetoprotein (AFP) level, portal vein cancerous thrombus, tumor metastasis, degree of lipiodol retention within the tumor, and percutaneous ethanol injection. The correlation between survival time and clinical variables of patients or lesions was analyzed by combining morphologic features with the corresponding clinical and general data as input. A Cox proportional hazard model was used to analyze prognostic factors. The Kaplan-Meier method was used to calculate the cumulative survival time. Influence of the parameters on prognosis was analyzed by the log-rank test. RESULTS: The overall 6, 12, 24, 36 and 60 mo cumulative survival rates were 78.92%, 49.85%, 23.82%, 15.60% and 8.92%, respectively. The median survival time was 12 mo. Univariate and multivariate analysis showed that only 4 parameters were the independent prognostic factors including TTLVR (chi(2) = 14.328, P < 0.001), portal vein cancerous thrombus (chi(2) = 5.643, P = 0.018), repeated TACE times (chi(2) = 8.746, P = 0.003), and post-treatment serum AFP level (chi(2) = 5.416, P = 0.020). When the TTLVR value was less than 70%, the survival time was inversely correlated with the TTLVR value. CONCLUSION: CT volume measurement technique can predict the prognosis of unresectable HCC patients after TACE.

Magnetic resonance angiography of carotid and cerebral arterial occlusion in rats using a clinical scanner.

In rat models to induce both focal cerebral ischemia and chronic cerebral hypoperfusion, it is highly desirable to verify the success of vessel occlusion and reopening with non-invasive method. The contrast-agent free 3D time-of-flight magnetic resonance angiography (TOF-MRA), diffusion-weighted imaging (DWI) and T2-weighted imaging by 3.0-T MR clinical scanner were applied when unilateral middle cerebral artery (MCA) was occluded and reopened, and after bilateral common carotid arteries were in ligation. The arterial angiograms of the rat brain and neck were achieved successfully in all chosen directions by the 3D TOF-MRA. It was shown that MCA in occlusion presented no signal in MRA, and the parenchyma of the ipsilateral MCA territory hypointensity signal in maps of apparent diffusion coefficient (ADC). After reperfusion, the signal intensity of ipsilateral MCA was resumed in MRA, and the decreased ADC was restored simultaneously. However, after 5h of reperfusion, it was found that the value of ADC deteriorated second time with high T2 value. In bilateral common carotid artery occlusion (BCCAO) rats, it can be confirmed by MRA that the effectively occluded BCCA presented the absent signal and the basilar artery became tortuous. As a result, MRA by clinical scanner was proved of a valuable method to validate transient middle cerebral artery occlusion (MCAO) and permanent BCCAO rat model.

Neuronal specificity of needling acupoints at same meridian: a control functional magnetic resonance imaging study with electroacupuncture.

The purpose of this study was to investigate the neuronal specificity of needling acupoints at same meridian by functional Magnetic Resonance Imaging (fMRI). The selected acupoints GB34 (Yanglinquan) and GB39 (Xuanzhong) were at the same gallbladder meridian based on traditional Chinese medicine. In our study we devise three distinct EA (electroacupuncture) manipulations: real EA (deep needling at acupoints), sham EA (deep needling at no-meridian points) and shallow EA (subcutaneous needling at acupoints). Twelve healthy volunteers with right-handiness were enrolled and received three different EA manipulations in counter-balanced orders. DeQi scores were used to evaluate the degree of needling sensation. We found real EA can induce significant stronger needling sensation than sham EA and shallow EA. Multisubjects group mean analysis showed that pain-related cortex including primary and secondary somatosensory cortex (SI and S II), anterior cingulated cortex (ACC), insula were involved in three EA stimulation. Bilateral activation of prefrontal gyrus and occipital cortex were exclusively found in real EA. Deactivation over the rostral segment of ACC was also shown in real and shallow EA. Further paired two difference analysis indicated that real EA induced higher activation than sham EA over bilateral prefrontal gyrus, right-side occipital gyrus and deactivation over the rostral segment of ACC. In the comparing with real EA versus shallow EA, there was right-side activation over the SI, S II, motor cortex, ACC, insula, thalamus, hippocampus, occipital cortex, and cerebellum; also activation over bilateral prefrontal gyrus, caudate and pons. Although no significant activation was found over periaqueductal gray (PAG), further analysis showed the mean and maximal signal changes were different under three EA manipulations. We concluded that EA at analgesic acupoints of same meridian maybe involved the pain-related neuromatrix especially the hypothalamus-limbic system; deep EA at meridian points could elicit stronger needling sensation and modulate the pain-related neuromatrix more effectively than EA at nonmeridian points or shallow EA at meridian points.

Characteristic magnetic resonance enhancement pattern in cerebral schistosomiasis.

OBJECTIVE: To describe the characteristic magnetic resonance imaging (MRI) appearance of cerebral schistosomiasis. METHODS: Twenty-five patients whose diagnosis of central nervous system (CNS) schistosomiasis had been pathologically (n = 8) and clinically (n = 17) confirmed were randomly selected. MRI was performed on a Signal 1. 5T MRI scanner before and after the intravenous administration of gadopentetate dimeglumine constrast medium. We reviewed the MRI studies obtained at the time of initial presentation, as well as follow-up studies obtained during and after medical treatment. RESULTS: Immunological tests in 15 patients indicated schistosomiasis haematobium. Contrast-enhanced T1-weighted images in 22 cases showed central linear enhancement surrounded by multiple enhancing punctate nodules, which appeared "arborized". Through operation and pathological examination, 8 cases had the granuloma formation of schistosomal eggs extensive surrounded by inflammation and venous congestion. And 17 cases were treated with praziquantel and corticosteroid therapy. And they were followed up for 2 months by taking MRI, which turned out to be complete resolution of the enhancing structure and edema. At follow-up, all the patients' initial symptoms also resolved. CONCLUSION: The specified MRI enhancement pattern of cerebral schistosomiasis is common in most cases of CNS schistosomiasis, so it should be taken account into the diagnosis of cerebral schistosomiasis.