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Although the altered coherence between cortical areas in Alzheimer's disease (AD) has been widely studied, it remains unclear whether the source-based coherence measures within sensorimotor network show significant difference between mild cognitive impairment (MCI) and AD. In the present study, resting-state electroencephalographic signals were recorded from 21 MCI and 21 mild AD patients. The spectral power and coherence in the sensorimotor areas were analyzed using the minimum norm estimate (MNE) combined with fast Fourier transform and coherence analysis in delta (1–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), beta (13–25 Hz), and gamma (25–40 Hz) bands. Our results indicated that source-based coherence in AD showed increased delta coherences between the bilateral precentral, left supplementary motor area (SMA) and right precentral, and left SMA and right postcentral areas. However, no significant difference of spectral powers was observed between AD and MCI. To conclude, the phenotype conversion from MCI to AD may be associated with an altered connectivity of the sensorimotor cortical network. This is a promising finding; however, further large-scale studies are needed.

Primary Sjögren’s syndrome (PSS) with central nervous system involvement may mimic the manifestations of multiple sclerosis (MS). The prevalence of PSS in MS patients varies in the published literature (0–16.6%), but has not yet been investigated in Asia, having a much lower MS prevalence than Western countries. Twelve consecutive patients presenting with a relapsing-remitting MS-like syndrome were recruited to assess the presence of PSS according to the American-European consensus group criteria. Six patients (50%) fulfilled the diagnostic criteria of PSS. The preliminary result suggests that PSS is an important differential diagnosis in patients with MS-like syndrome in Taiwan. The prevalence of ‘pure MS’ in Taiwan might be even lower than expected. A further large-scale study is warranted to confirm this finding in Taiwan as well as other Asian countries.

Brain functional networks based on resting-state EEG data were compared between patients with mild Alzheimer’s disease (mAD) and matched patients with amnestic subtype of mild cognitive impairment (aMCI). We integrated the time–frequency cross mutual information (TFCMI) method to estimate the EEG functional connectivity between cortical regions and the network analysis based on graph theory to further investigate the alterations of functional networks in mAD compared with aMCI group. We aimed at investigating the changes of network integrity, local clustering, information processing efficiency, and fault tolerance in mAD brain networks for different frequency bands based on several topological properties, including degree, strength, clustering coefficient, shortest path length, and efficiency. Results showed that the disruptions of network integrity and reductions of network efficiency in mAD characterized by lower degree, decreased clustering coefficient, higher shortest path length, and reduced global and local efficiencies in the delta, theta, beta2, and gamma bands were evident. The significant changes in network organization can be used in assisting discrimination of mAD from aMCI in clinical., {"references":["R. C. Petersen, \"Early diagnosis of Alzheimer's disease: is MCI too\nlate?,\" Current Alzheimer Research, vol. 6, p. 324, 2009.","A. Pozueta, E. Rodríguez-Rodríguez, J. L. Vazquez-Higuera, I. Mateo, P.\nSánchez-Juan, S. González-Perez, J. Berciano, and O. Combarros,\n\"Detection of early Alzheimer's disease in MCI patients by the\ncombination of MMSE and an episodic memory test,\" BMC neurology,\nvol. 11, p. 78, 2011.","S. Landau, D. Harvey, C. Madison, E. Reiman, N. Foster, P. Aisen, R.\nPetersen, L. Shaw, J. Trojanowski, and C. 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Miller Fisher syndrome (MFS), characterized as ataxia, areflexia and ophthalmoplegia, is generally considered as a variant of Guillain-Barré syndrome (GBS). However, some investigators believed that the syndrome could be explained by a central origin. To obtain more information about MFS for comparison with GBS, we conducted a retrospective study by analyzing the clinical data of MFS patients admitted to our hospital over a period of 11 years. The calibrated male/female ratio was 1.65. A seasonal clustering in winter was noted. The percentage of MFS among GBS was especially high (18%, 11/60) in Taiwan when compared with other series. Involvement of limb muscle strength, autonomic function and cranial nerves, except ocular motor nerves, was rarely found in our patients. When MFS is accompanied by limb weakness, it might represent a transitional form between MFS and GBS. Bulbar palsy and dysautonomia might predict a relatively poor prognosis. To obtain more reliable information, lumbar puncture should be done 1 week after disease onset, and electrophysiological tests should be done serially in every MFS patient. Eighty percent (80%, 4/5) of our patients were positive for IgG anti-GQ1b antibody activity. In our study, there is more evidence indicating that MFS is a peripheral nervous system disorder; however, no definite conclusion could be made as to whether MFS is exclusively a peripheral or central nervous system disorder. We think MFS is an immune-mediated clinical entity which mainly involves the peripheral nervous system with rare involvement of other parts of the central nervous system.

The aim of this study is to assess whether additional median -to-ulnar comparative tests will improve the diagnostic rate of carpal tunnel syndrome (CTS).We recruited 248 hands of 162 CTS patients, and 166 hands of 83 controls. One hundred and sixty-eight (68%) symptomatic hands had abnormal median distal latencies or palm-wrist latencies. We performed three additional comparative tests in the remaining symptomatic hands and the non-CTS hands. The first test compared median distal motor latency (MDL) recorded from the second lumbrical muscle (2L) and ulnar distal latency recorded from interossei muscles (INT) (2L-INT). The second test compared median and ulnar antidromic sensory latencies (MS-US). And the third test compared median and ulnar nerve latencies in the palm-to-wrist segment (PM-PU).In control subjects, upper limits of median-to-ulnar differences were: 2L-INT= 0.4 ms, MS-US= 0.5 ms, PM-PU= 0.4 ms. In CTS patients with normal conventional electrodiagnostic methods, MS-US difference showed the lowest sensitivity (21.3%). The diagnostic sensitivity of 2L-INT was 27.5% and PM-PU 47.5%. With PM-PU test, additional 15.3% diagnostic rate could be got.For CTS patients with normal results from the standard methods, PM-PU is a good additional comparative test to further improve diagnostic rate.

Some researchers have suggested that the default mode network (DMN) plays an important role in the pathological mechanisms of Alzheimer's disease (AD). To examine whether the cortical activities in DMN regions show significant difference between mild AD from mild cognitive impairment (MCI), electrophysiological responses were analyzed from 21 mild Alzheimer's disease (AD) and 21 mild cognitive impairment (MCI) patients during an eyes closed, resting-state condition. The spectral power and functional connectivity of the DMN were estimated using a minimum norm estimate (MNE) combined with fast Fourier transform and imaginary coherence analysis. Our results indicated that source-based EEG maps of resting-state activity showed alterations of cortical spectral power in mild AD when compared to MCI. These alterations are characteristic of attenuated alpha or beta activities in the DMN, as are enhanced delta or theta activities in the medial temporal, inferior parietal, posterior cingulate cortex and precuneus. With regard to altered synchronization in AD, altered functional interconnections were observed as specific connectivity patterns of connection hubs in the precuneus, posterior cingulate cortex, anterior cingulate cortex and medial temporal regions. Moreover, posterior theta and alpha power and altered connectivity in the medial temporal lobe correlated significantly with scores obtained on the Mini-Mental State Examination (MMSE). In conclusion, EEG is a useful tool for investigating the DMN in the brain and differentiating early stage AD and MCI patients. This is a promising finding; however, further large-scale studies are needed.

Objective. The argument about why the head-up tilt table test (HUT) does not include the posterior cerebral circulation, which is mainly responsible for syncope, as a monitor target has not been resolved. It is also unclear whether there is a sex difference in cerebral blood flow (CBF) changes. We hypothesized that orthostatic CBF changes more in the posterior circulation than in the anterior circulation and is different between sexes. Methods. Thirty healthy volunteers (13 female and 17 male) were recruited for the HUT. The blood pressure (BP), middle cerebral artery flow velocity (MCAFV), and posterior cerebral artery flow velocity (PCAFV) were monitored simultaneously. Static cerebral autoregulation (CA) was calculated. Results. The female volunteers had a lower BP, but there was no difference in orthostatic BP changes (female versus male: 1.29% ± 5.26% versus 4.22% ± 12.65%; P = .65). The female volunteers had a significantly greater orthostatic drop in the PCAFV than in the MCAFV (23.8% ± 9.1% versus 18.2% ± 7.3%; P = .008). The static CA in the middle cerebral artery was better than in the posterior cerebral artery, although not significantly (13.6% ± 34.8% versus –2.8% ± 12.2%; P = .15). Conclusions. Our study showed the different cerebral hemodynamic responses between anterior and posterior circulations and between sexes during the HUT. We conclude that HUT studies for syncope should include the posterior cerebral circulation, especially for female patients. Key words: autoregulation; cerebral blood flow; head-up tilt table test; syncope; transcranial Doppler ultrasound.

Cerebral venous outflow insufficiency via the internal jugular vein (IJV) is associated with several neurological disorders. However, a normal reference set of IJV hemodynamic parameters derived from a large, healthy population over a wide range of age has, until now, been lacking. Color-coded duplex sonography was performed on the IJVs of 349 subjects (55.60 ± 17.49,16 to 89 y; 167 M/182 F). With increasing age, increased lumen area and decreased time-averaged mean velocity of bilateral IJV and a decreased proportion of total flow volume, drainage in the left IJV were found. The frequency of left jugular venous reflux (JVR) also increased with aging. We report IJV hemodynamic parameters across a large population, which could be used as a normal reference for clinical and research purposes. Furthermore, we found a decreased proportion of venous drainage, increased JVR prevalence, dilated lumen and slowed flow velocity in the left IJV, all of which suggest increased left IJV outflow impedance with aging.

Background.—Idiopathic hypertrophic cranial pachymeningitis (IHCP) is an uncommon disorder due to localized or diffuse thickening of the dura mater. While headache is the most common manifestation, the clinical characteristics of the headache in IHCP have not been well characterized. Methods.—From 1996 to 2002, 6 consecutive patients with IHCP presenting with headache were reviewed (3 women, 3 men; mean age: 49 years). Diagnosis was based on characteristic neuroimaging findings and the exclusion of secondary causes of cranial pachymeningitis. This study reported the headache characteristics, neuroimaging features, and longitudinal follow-up. Results.—Chronic daily headache, especially chronic migraine, was the most common headache pattern observed (4/6 patients). Lateralization of headache location appeared to correlate with the distribution of the hypertrophied dural lesions. Diagnostic delay was due to failure to evaluate with gadolinium-enhanced MRI. After treatment, headache (5/6, 83%) and neurologic deficits (2/3, 67%) improved in most patients; however, follow-up MRIs (n = 5) showed deterioration in 3 patients. Conclusion.—The headache of IHCP is typically a chronic daily headache, often resembling chronic migraine. Correspondingly, IHCP should be considered in the differential diagnosis of refractory chronic daily headache, with or without associated cranial neuropathy or other associated neurologic deficits. The typical imaging finding on gadolinium-enhanced MRI is localized or diffuse pachymeningitis and failure to order a gadolinium-enhanced MRI is the primary reason for delayed diagnosis. Despite symptomatic improvement on longitudinal follow-up, the MRI abnormalities may not improve in parallel with the clinical symptoms.

To obtain more information about Guillain-Barré syndrome (GBS) for Taiwanese patients.We retrospectively reviewed the charts for those cases conforming with International Classification of Diseases code (ICD) 357.0, from January 1988 to December 1998. Clinical data such as age, sex, duration of hospitalization, antecedent events, date of onset, initial symptoms, other neurological symptoms and signs, results of lumbar puncture and electrophysiology, respiratory function and mortality, were recorded.We identified 49 cases of typical GBS, with non-specific age distribution. The calibrated male/female ratio was 1.54. The mean age for disease onset was greater for male patients (M: 54.8 years vs. F: 39.5 years), with more cases noted in winter. Upper respiratory tract infection (URI, 53%) was the most common antecedent event, followed, in descending order, by gastrointestinal symptoms (10%), skin lesions (6%) and ear infections (2%). The mean interval between antecedent events and disease onset was 10 +/- 3.1 days. Cranial nerve abnormalities, autonomic dysfunction and respiratory failure were not uncommon. The mortality rate was 6% (3/49). The abnormal findings from motor nerve conduction studies included prolonged distal latencies, reduced conduction velocities, reduced compound muscle action potentials and prolonged F-wave latencies.GBS occurs at all ages, is more prevalent among males, and is related to the season and antecedent infections. Continuous monitoring of autonomic and respiratory function is recommended. The results of motor nerve conduction studies suggest that the nerves fibers are affected at random, with multifocal distribution of the demyelinating lesions. The precise nature of the ataxia was not determined. Further studies are required to distinguish the etiology and expression of ataxia for GBS patients.