Guillain-Barré Syndrome After COVID-19 Infection in Korea: A Case Series.

Guillain-Barré syndrome (GBS) is an autoimmune-driven condition characterized by acute polyneuropathy, often emerging as a sequel to prior infections or vaccinations. This study presents the first reported cases of GBS emerging after the full recovery from coronavirus disease 2019 (COVID-19) infection in Korea. Despite experiencing mild acute COVID-19 symptoms, these patients faced substantial weakness attributed to GBS, significantly affecting their daily lives. The timely administration of intravenous immunoglobulin treatment halted the progression of symptoms, underscoring the critical importance of early intervention. These cases highlight the potential for neurological complications associated with COVID-19 and underscore the necessity for continuous monitoring and timely medical care.

Recurrent Transient Neurological Deficit Due to Intracerebral Steal Phenomenon in Association with a Developmental Venous Anomaly.

We report a symptomatic developmental venous anomaly (DVA) not causing parenchymal abnormality to provide a pathophysiologic clue in patients with recurrent transient neurologic deficit. A 32-year-old male presented with recurrent transient motor aphasia and headache in the left fronto-temporal region for three years. The symptoms usually lasted for one hour. Brain computed tomography (CT) angiography and magnetic resonance imaging using gradient recalled echo showed a prominent penetrating vein at the left frontal periventricular region. Brain CT perfusion imaging performed during the symptoms revealed increased perfusion in the corresponding area with relatively decreased perfusion in the left fronto-temporal cortices. Digital subtraction angiography revealed collecting venous blood from the left septal and thalamostriate veins draining into the left cavernous sinus without early arteriovenous shunting. In this patient, an inciting incident might have led to imbalance of the venous flow surrounding the DVA, causing venous hypertension and the intracerebral steal phenomenon in the surrounding area. The relatively hypoperfused cortical area adjacent to the DVA could be considered the cause of the transient motor aphasia, while venous hypertension could be the cause of the headache.

Association of arterial stiffness with cognition in patients with Lewy body disorder.

The brachial-ankle pulse wave velocity (baPWV) is a marker for arterial stiffness, which is associated with cardiovascular diseases. Arterial stiffness is associated with cognitive function in the elderly and patients with Alzheimer's disease (AD). We aimed to investigate the association between arterial stiffness and cognitive function in patients with Lewy body disorder (LBD), including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). We consecutively included 123 patients with PD, 10 patients with DLB, and 27 AD controls. Patients with PD were divided into three groups of normal cognition (PD-NC, n = 63), mild cognitive impairment (PD-MCI, n = 43), and dementia (PD-D, n = 17). Arterial stiffness, measured as baPWV, was compared between the PD-NC, PD-MCI, PD-D, DLB, and AD patients. In LBD, we analyzed the association between arterial stiffness and each cognitive domain with adjustment for covariates. Higher baPWV was significantly associated with cognitive decline in patients with LBD (baPWV in PD-D > PD-MCI > PD-NC; DLB > PD-NC). There was no significant difference in baPWV between PD-D, DLB, and AD patients. In LBD patients, higher baPWV was associated with lower mini mental state examination score (ß ± SE = -0.003 ± 0.001, p = 0.007) and more severe dementia. Higher baPWV was also associated with lower performance in attention, language, visuospatial function, memory, and executive function in LBD patients. This suggests that vascular brain injury is associated with cognitive dysfunction in LBD.

Arterial Stiffness and Cardiovascular Autonomic Dysfunction in Patients with Parkinson's Disease.

BACKGROUND: Pulse wave velocity is a marker of arterial stiffness and a surrogate marker of vascular damage. Autonomic abnormalities associated with blood pressure are relatively commonly observed in patients with Parkinson's disease (PD). OBJECTIVE: The purpose of this study was to compare arterial stiffness between patients with PD and controls and investigate the associations between cardiovascular autonomic dysfunction and pulse wave velocity in PD. METHODS: One hundred twenty-five PD patients without diabetes mellitus were enrolled into this study, along with 22 age-matched controls. Orthostatic vital signs and ambulatory 24-hour blood pressure monitoring values were recorded. Pulse wave velocity was used to evaluate arterial stiffness. RESULTS: In PD, greater arterial stiffness was associated with orthostatic hypotension, supine hypertension, nocturnal hypertension, and nondipping. Dopaminergic treatment did not influence cardiovascular autonomic dysfunction or arterial stiffness. Although pulse wave velocity was mildly increased in patients with PD compared to controls, the arterial stiffness in PD patients without autonomic failure was similar to that in normal controls. Stiffer arteries were found only in patients with PD and autonomic failure. CONCLUSION: These findings suggest that cardiovascular autonomic dysfunction is associated with arterial stiffness in PD. PD itself does not affect arterial stiffness, whereas autonomic blood pressure disturbances influence alterations in arterial stiffness and architectural changes in the arteries of PD patients.

Arterial stiffness and impaired renal function in patients with Alzheimer's disease.

Impaired renal function is regarded as a risk factor for vascular disease, and is associated with an increasing pulse wave velocity. Both renal dysfunction and arterial stiffness are associated with cognitive impairment and dementia. However, there have been few studies that have evaluated the relationship between albuminuria and arterial stiffness and Alzheimer's disease (AD). We investigated renal dysfunction and arterial stiffness in AD, as compared to normal controls, patients with subjective memory impairment (SMI), and patients with mild cognitive impairment (MCI). Case-control comparisons were made between 29 patients with AD, 27 with MCI, 14 with SMI, and 25 healthy controls. All patients underwent clinical and neuropsychological assessments. The urine albumin/creatinine ratio and estimated glomerular filtration rate (eGFR) were determined. Pulse wave velocity and the ankle-brachial index were used to evaluate arterial stiffness. The urine albumin/creatinine ratio and eGFR were significantly different in patients with AD, compared with the results from cognitive normal controls. The pulse wave velocity was increased and the ankle-brachial index was decreased in AD. The eGFR was well correlated with other indices and decreasing eGFR was independently associated with cognitive decline. In conclusion, albuminuria, a decreased glomerular filtration rate, an increased pulse wave velocity, and a decreased ankle-brachial index were associated with AD. These finding suggests that impaired renal functions and arterial stiffness are related to AD, in which a vascular mechanism plays a prominent role in the cognitive dysfunction associated with the disease.

Cardiovascular autonomic dysfunctions in elderly patients with essential tremor: comparison with healthy controls.

Questionnaire-based analyses show that patients with essential tremor (ET) may have several autonomic dysfunctions, especially in the cardiovascular and genitourinary domains; yet the laboratory correlates of autonomic dysfunction in ET are unknown and have not been studied. Herein, we explored whether sympathetic and parasympathetic functions differed between control subjects and patients with ET. Seventy-five elderly patients with ET were enrolled in this study, along with 25 age-matched controls. Orthostatic vital signs, ambulatory 24-h blood pressure monitoring and 24-h Holter monitoring values were recorded and metaiodobenzylguanidine (MIBG) uptake was assessed using the heart-to-mediastinum ratio (H/M ratio). The frequencies of orthostatic hypotension, supine hypertension, nocturnal hypertension and non-dipping were not different between the ET patients and the controls, although ET patients had more episodes of orthostatic intolerance. The ET group also had similar heart rate variations as the control group for all the time-domains. The mean H/M ratios for the ET group were not statistically different from that of the control group. This result proves that the autonomic control of the cardiovascular system is normal in ET.

Cognitive correlates of cerebral vasoreactivity on transcranial Doppler in older adults.

BACKGROUND: This study was performed to explore the possible contributions of cerebral hemodynamic changes to the cognitive impairment in patients with Alzheimer's disease (AD). METHODS: A total of 194 participants were included: 52 controls, 75 patients with mild cognitive impairment (MCI), and 67 patients with AD. Demographic characteristics, vascular risks, mini-mental state examination (MMSE), and clinical dementia rating (CDR) were assessed, and magnetic resonance imaging of the brain was performed to evaluate white matter hyperintensities (WMHs). Using transcranial Doppler (TCD) ultrasonography, cerebrovascular reactivity (CVR) was evaluated with a breath-holding test, in addition to the mean blood flow velocity (MFV), pulsatility index (PI), and resistance index (RI) of the middle cerebral artery. RESULTS: After adjusting for covariates such as age, education, WMH severity, and vascular risks, TCD parameters such as MFV, PI, and RI did not differ between the 3 groups. However, CVR was significantly reduced in the AD group (45.33 ± 11.49%), compared with the other groups (56.36 ± 14.65%, controls; 53.84 ± 15.47%, MCI group; P < .001). Multiple regression analyses also showed that CVR was associated with MMSE scores. CVR differed according to the CDR scores (P < .001). CONCLUSIONS: Our finding may be suggestive of an underlying microangiopathic mechanism in AD patients. Furthermore, there was an association between the impaired function of cerebral microvessels and cognitive impairment. Further research is needed to fully establish whether altered cerebral hemodynamics may be considered an independent factor in predicting cognitive decline or an effect of pathologic processes involved in AD.

Disability weight for each level of the Expanded Disability Status Scale in multiple sclerosis.

BACKGROUND: The Expanded Disability Status Scale (EDSS) is the most widely employed ordinal disability scale in multiple sclerosis (MS). However, how far apart the individual EDSS levels are along the disability spectrum has not been formally quantified. OBJECTIVES: The objective of this paper is to generate refined disability weights (DWs) for each of the ordinal EDSS levels. METHODS: We performed the person trade-off (PTO) procedure to derive DWs of five representative EDSS categories (2, 4, 6, 7 and 9), and DWs of the remaining EDSS categories were assigned by linear interpolation. The modified Delphi process was used to achieve consensus among raters. RESULTS: DWs were 0.021 for EDSS 2, 0.199 for EDSS 4, 0.313 for EDSS 6, 0.617 for EDSS 7, and 0.926 for EDSS 9. Panel members achieved a high degree of consensus for each DW, as indicated by low coefficients of variation. CONCLUSIONS: Our DWs confirmed that EDSS is an ordinal scale with highly variable intervals. The availability of DW for each EDSS level allows direct comparison of each MS outcome state with other health states and provides a foundation for the estimation of the disability-adjusted life-years lost of individual patients.

The influence of factors associated with past reproductive histories on migraines in middle-aged premenopausal women: a nationwide population-based study in Republic of Korea.

Introduction: Women can experience various reproductive events, such as pregnancy, childbirth, lactation, and contraception, which cause long-term changes in female hormones. In middle-aged women, the prevalence of migraine is high, and a clear gender difference is evident. This study investigated the effects of factors associated with past reproductive events on the risk of new migraine in middle-aged premenopausal women. Methods: The influence of reproductive factors on migraine in middle-aged women was investigated using the Korean National Health Insurance Service (KNHIS) and Korean Health Examination (KHE) databases. The reproductive factors of interest were parity, breastfeeding, and oral contraceptive (OC) use. The study included 949,704 middle-aged premenopausal women 40-60 years of age. The study population was divided into two groups based on new diagnosis of migraine during the follow-up period (2009-2018). Results: The risk of new migraine tended to increase in the primiparous (hazard ratio, HR: 1.179; 95% confidence interval, CI: 1.137-1.221) and multiparous groups (HR: 1.181; 95% CI: 1.142-1.221) compared with the nulliparous group. The breastfeeding ≥12 months group (HR: 1.071; 95% CI: 1.052-1.091) showed a significantly increased risk of new migraine compared with the non-breastfeeding group. All women in the OC groups (< 1 year, HR: 1.048; 95% CI: 1.028-1.069 and ≥ 1 year, HR: 1.100; 95% CI: 1.067-1.134) showed a higher risk of new migraine than those in the non-OC group. Conclusion: The results of the current study indicate that childbirth, longer breastfeeding, and OC use may be associated with a higher risk of new migraine in middle-aged premenopausal women.

Clinical pitfalls and serological diagnostics of MuSK myasthenia gravis.

BACKGROUND: We aimed to evaluate the diagnostic accuracy of enzyme-linked immunosorbent assay (ELISA) for anti-muscle specific tyrosine kinase (MuSK) antibody (Ab) in a large cohort of anti-acetylcholine receptor (AChR) Ab-negative generalized myasthenia gravis (MG), and also to investigate clinical contexts for the diagnosis of MuSK MG. METHODS: A retrospective study of 160 patients with a clinical suspicion of AChR Ab-negative generalized MG was performed. The serum samples were tested for anti-clustered AChR Ab by cell-based assay (CBA), anti-MuSK Ab by ELISA, CBA and/or radioimmunoprecipitation assay (RIPA). Clinical data were compared between anti-MuSK Ab-positive MG and double seronegative (AChR and MuSK) MG groups. RESULTS: After excluding non-MG and clustered AChR Ab-positive patients, we identified 89 patients as a cohort of AChR Ab-negative generalized MG. Anti-MuSK Ab was positive by ELISA in 22 (24.7%) patients. While CBA identified five additional anti-MuSK Ab-positive patients, the results of ELISA were mostly consistent with CBA and RIPA with Cohen's kappa of 0.80 and 0.90, respectively (p < 0.001). The most frequent differential diagnosis was motor neuron disease particularly of bulbar onset which showed remarkably overlapping clinical and electrophysiological features with MuSK MG at presentation. CONCLUSION: While confirming the highest sensitivity of CBA for detecting anti-MuSK Ab, our results highlight the clinical pitfalls in making a diagnosis of MuSK MG and may support a diagnostic utility of MuSK-ELISA in clinical practice.

Cross-sectional area reference values for high-resolution ultrasonography of the lower extremity nerves in healthy Korean adults.

The cross-sectional area (CSA) reference values of the lower extremity nerves in Asians have been rarely reported. For this study, 107 sex- and age-matched, healthy subjects with a mean age of 46 years (range, 24-75 years) were recruited. All subjects underwent standardized nerve conduction studies of the upper and lower extremities. The CSA was measured unilaterally at 12 sites in the lower extremity nerves, including the femoral, lateral femoral cutaneous, sciatic, common peroneal, superficial peroneal, deep peroneal, tibial, and sural nerves. The CSA significantly correlated with height, weight, and body mass index. The CSA was significantly larger in males than females at most nerves except for the lateral femoral cutaneous, common peroneal (fibular head), and superficial peroneal nerves (distal calf). There was no statistically significant difference between the age groups except for the tibial nerve (ankle). The results of this study provide CSA reference values for the lower extremity nerves including small branches and the values can be useful in the ultrasonographic investigation of various peripheral neuropathies in East Asian populations.

Posterior Interosseous Fascicular Constriction Within the Radial Nerve in a Diabetic Patient With Bilateral Neuralgic Amyotrophy: A Case Report.

Background: Neuralgic amyotrophy (NA) is an acute, monophasic, painful inflammatory dysimmune focal, or multifocal mononeuropathy. The lesion in NA is not always restricted to the brachial plexus but also involves individual nerves or branches. The prognosis of NA is less favorable than previously assumed, but the reasons for poor recovery remain unknown. Nerve constriction may be one of the causes of poor prognosis in NA. Case Presentation: Herein, we described a 54-year-old male with a history of type 2 diabetes in whom bilateral neuralgic amyotrophy developed with constriction of the posterior interosseous fascicle within the radial nerve. The patient experienced sudden-onset severe pain in both shoulders followed, 2 days later, by weakness in bilateral shoulders and the left forearm extensors over the subsequent month. The left forearm extensors were more severely affected than both shoulder girdle muscles. He noted a 7-kg weight loss for 1 month before pain onset. After diagnosing diabetic NA based on the clinical symptoms, imaging, and electrophysiological studies, treatment with systemic steroids improved pain and weakness in both shoulder muscles. Weakness in the left forearm extensors persisted after 1 month of steroid treatment. Follow-up ultrasound revealed constriction of the posterior interosseous fascicle within the main trunk of the left radial nerve at the elbow. Surgical exploration at 6 months after onset identified fascicle constriction, for which neurolysis was performed. Weakness in the extensors of the wrist and fingers did not improve during the 16-month follow-up. Conclusion: A single constriction of the fascicle within a peripheral nerve may often be under-recognized if NA presents with variable degrees of weakness in bilateral upper limbs. Furthermore, fascicular constriction without edema of the parent nerve may be easily missed on the initial ultrasound. A lack of early recognition of nerve constriction and delay in surgical intervention can result in unfavorable outcomes. The physician should consider the possibility of the fascicular constriction when evaluating patients suspected of brachial NA with significant weakness in the distal upper limb compared to the proximal weakness or weakness of the distal upper limb that does not improve over time.

Cross-sectional area reference values for high-resolution ultrasonography of the upper extremity nerves in healthy Asian adults.

ABSTRACT: In this study, multiple-site, cross-sectional area (CSA) reference values were established for major peripheral nerves, including small branches, in the upper extremity of a healthy Asian population.This study included 107 prospectively recruited age-matched, healthy subjects with a mean age of 46 years (range, 24-75 years). All subjects underwent standardized nerve conduction studies for the median, ulnar, peroneal, posterior tibial, and sural nerves. CSA was measured unilaterally at 21 sites of the median, ulnar, radial, posterior interosseous, superficial radial sensory, musculocutaneous, lateral antebrachial cutaneous, and medial antebrachial cutaneous nerves.According to their age, the subjects were assigned to the younger group (20-40 years, n = 40), the middle group (40-59 years, n = 40), and the older group (60-80 years, n = 27). The significant differences of CSA values between age groups were found only at certain sites, such as the median (wrist, P = .003), ulnar (medial epicondyle, P = .031; forearm, P = .022), radial (antecubital fossa, P = .037), and superficial radial sensory nerve (P = .028). The CSA significantly correlated with gender, height, weight, and body mass index.This study provides CSA reference values for nerves, including small sensory nerves in the upper extremity, which can be useful in the ultrasonographic investigation of various peripheral neuropathies in the upper extremity.

Paramagnetic Rims in Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorder: A Quantitative Susceptibility Mapping Study with 3-T MRI.

BACKGROUND AND PURPOSE: Iron retained by activated microglia and macrophages in multiple sclerosis (MS) lesions may serve as a marker of innate immune system activation. Among several magnetic resonance imaging (MRI) methods, there has been recent interest in using quantitative susceptibility mapping (QSM) as a potential tool for assessing iron levels in the human brain. This study examined QSM findings in MS and neuromyelitis optica spectrum disorder (NMOSD) lesions obtained with 3-T MRI to assess imaging characteristics related to paramagnetic rims around brain lesions in MS and NMOSD. METHODS: This study included 32 MS and 21 seropositive NMOSD patients. MRI images were obtained using two 3-T MRI devices (Ingenia, Philips Healthcare; and Magnetom Verio, Siemens Healthineers) during routine diagnosis and treatment procedures. Multi and single echo gradient echo magnitude and phase images were obtained for QSM reconstruction. QSM images were used to characterize the detected lesions, and the findings were compared between MS and NMOSD. RESULTS: Totals of 71 and 35 MRI scans were performed during the study period in MS and NMOSD patients, respectively. In QSM images, paramagnetic rims were found in 26 (81.2%) MS patients and 1 (4.8%) NMOSD patient. Eight of the 22 MS patients and only 1 of the 10 NMOSD patients who underwent follow-up MRI showed new paramagnetic rims. The paramagnetic rim lesions appeared after enhancement or in new T2-weighted lesions without enhancement. CONCLUSIONS: Paramagnetic rims might be a characteristic MRI finding for MS, and therefore they have potential as an imaging marker for differentially diagnosing MS from NMOSD using 3-T MRI.

Poststroke restless legs syndrome and lesion location: anatomical considerations.

Several case studies have reported on restless legs syndrome (RLS) associated with stroke. In this study, we investigated the prevalence and the lesion topography of poststroke RLS. There were 137 patients with ischemic stroke included in this study. The diagnosis of RLS was made 1 month after the index stroke using the criteria established by the International RLS Study Group. All patients enrolled underwent magnetic resonance imaging within 7 days of the onset of the stroke. The prevalence of stroke-related RLS was calculated, and the topography of the associated ischemic lesions was analyzed. Among 137 patients, 17 patients (12.4%) were diagnosed with RLS after a stroke. Stroke-related RLS was found in 10 out of 33 patients with a basal ganglia/corona radiata infarct (30.3%), 1 out of 8 patients with an internal capsular infarct (12.5%), and 1 out of 7 patients with a thalamic infarct (14.3%). In addition, one out of 54 with a cortical lesion with/without subcortical involvement (1.9%), and 4 out of 18 patients with a pontine lesion (22.2%) had RLS. The analysis of the lesions in the cortical and subcortical group showed only 1 patient in the cortical group had stroke-related RLS, whereas 16 in the subcortical group had stroke-related RLS. The results of this study suggest that lesions of the subcortical brain areas such as the pyramidal tract and the basal ganglia-brainstem axis, which are involved in motor functions and sleep-wake cycles, may lead to RLS symptoms in patients after an ischemic stroke.

The relationship between low bone mineral density and Parkinson's disease in a Korean population.

There have been few studies concerning osteoporosis in patients with Parkinson's disease (PD), even though patients with PD have a high incidence of falls. Using a Korean population, we investigated the association between bone mineral density (BMD) and PD. A total of 107 patients with PD were compared with age-matched and sex-matched normal controls. Using the Hoehn & Yahr staging system, we classified the patients with PD into three subgroups. Parts II and III of the Unified Parkinson's Disease Rating Scale were administered to evaluate the relationship between the severity of PD and BMD. In conclusion, in the PD population we found that decreased BMD was related to the severity of immobility of patients, and that BMD changes were greater at the femoral neck than the spine area. Therefore, we assert that clinicians should consider administering screening tests to elderly patients with PD and provide appropriate primary or secondary prophylactic treatment for osteoporosis.

The leukoaraiosis is more prevalent in the large artery atherosclerosis stroke subtype among Korean patients with ischemic stroke.

BACKGROUND: Several studies have suggested that the specific stroke subtype may influence the presence of leukoaraiosis in patients with ischemic stroke. We investigated the association between stroke subtype and leukoaraiosis in Korean patients with ischemic stroke by MRI. METHODS: There were 594 patients included in this study that were classified as large artery disease, lacune and cardioembolic stroke. For large-artery disease, the analysis focused on the intracranial or extracranial location of the stenosis, and the multiplicity of the stenotic lesions. Leukoaraiosis grading was performed according to the Atherosclerosis Risk in Communities Study. RESULTS: There was a significant association between leukoaraiosis and the stroke subtypes; the large-artery-disease group had a higher prevalence of leukoaraiosis than did the other groups (55.4% in the large-artery-disease group, 30.3% in the lacunar group and 14.3% in the cardioembolic group, P = 0.016 by chi-square test). On the multivariate linear regression analysis, age, the presence of hypertension, previous stroke and stroke subtype were independently associated with the presence of leukoaraiosis. In the sub analysis of the large-artery-disease group, the leukoaraiosis had a tendency to be more prevalent in the mixed and intracranial stenosis group than did the extracranial stenosis group (45.5% in the mixed group, 40.3% in the intracranial group and 26.9% in the extracranial group, P = 0.08 by chi-square test). CONCLUSION: The association of leukoaraiosis with large-artery disease in this study might be due to the relatively high prevalence of intracranial occlusive lesions in Korean stroke patients compared to other ethnic groups.

The lesion patterns and mechanisms of ischemic stroke contralateral to the internal carotid artery occlusive disease.

BACKGROUND: In previous studies on unilateral internal carotid artery (ICA) occlusive disease, contralateral strokes have been ignored or excluded, probably because of their heterogeneity in etiology. The purpose of this study was to analyze the acute ischemic lesions contralateral to ICA occlusive disease and characterize the patterns and mechanisms of these strokes. METHODS: Eight patients, who had an acute ischemic stroke contralateral to the ICA occlusion, were enrolled. All patients underwent routine clinical evaluation including history and physical examination, laboratory tests and magnetic resonance imaging (MRI). Both magnetic resonance angiography and digital subtraction cerebral angiography, along with carotid duplex sonography, transcranial Doppler sonography, electrocardiography and echocardiography were performed to confirm the stroke subtypes. RESULTS: There were three distinctive stroke lesion patterns: (1) multiple infarcts in the border zone with or without a territorial lesion (4 patients), (2) multiple infarcts in the arterial territories sparing the border zone (2 patients), and (3) a small (<15 mm in MRI) single infarct in the internal border zone (2 patients). Overall, the patterns of ischemic lesions contralateral to the ICA occlusion were multiple and had a border zone distribution. CONCLUSION: These results suggest that the pathogenic mechanisms underlying these strokes could be the synergistic effects of both the embolism and a low flow state.