Neurology International最新文献

Background/objectives: Small-vessel occlusion, previously referred to as lacunar infarcts, accounts for approximately one-third of all ischemic strokes, using an axial diameter of less than 20 mm on diffusion-weighted imaging. However, this threshold may not adequately differentiate small-vessel occlusion from other pathologies, such as branch atheromatous disease (BAD) and embolism. This study aimed to assess the clinical significance and pathological implications of acute small subcortical infarctions (SSIs) based on infarct diameter.

Methods: We conducted a retrospective case-control study using data from stroke patients recorded between 2016 and 2021 of the Stroke Registry in Chang Gung Healthcare System. Patients with acute SSIs in penetrating artery territories were included. Key variables such as patient demographics, stroke severity, and medical history were collected. Infarcts were categorized based on size, and the presence of early neurological deterioration (END) and favorable functional outcomes were assessed.

Results: Among the 855 patients with acute SSIs, the median age was 70 years and the median National Institutes of Health Stroke Scale (NIHSS) score at arrival was four. END occurred in 97 patients (11.3%). Those who experienced END were significantly less likely to achieve a favorable functional outcome compared to those who did not (18.6% vs. 59.9%, p < 0.001). The incidence of END increased progressively with infarct sizes of 15 mm or larger, with the optimal threshold for predicting END identified as 15.5 mm and for BAD, it was 12.1 mm. A multiple logistic regression analysis revealed that motor tract involvement [adjusted odds ratio (aOR) 2.3; 95% confidence interval (CI) 1.1-4.7], an initial heart rate greater than 90 beats per minute (aOR 2.3; 95% CI 1.2-4.3), and a larger infarct size (15 mm to less than 20 mm vs. 10 mm to less than 15 mm; aOR 3.0; 95% CI 1.4-6.3) were significantly associated with END.

Conclusions: Our findings suggest that setting the upper limit for small-vessel occlusion at 15 mm would be more effective in distinguishing it from BAD. However, these findings should be interpreted in the context of the retrospective design and study population. Further multi-center research utilizing high-resolution vessel wall imaging is necessary to refine this threshold and enhance diagnostic accuracy.

Embryologically, the left brachiocephalic vein (LBV) originates as an anastomotic channel between the right and left anterior cardinal veins. This positions the LBV between the manubrium sterni anteriorly and the innominate artery posteriorly. This pattern of adjacency of the aorta to the LBV is unique to mammals and results from a quirk of evolution. With age, the ascending aorta unfolds, elongates and dilates. Simultaneously, there is a change in the thoracic geometry that reduces the thoracic volume primarily from disc height loss and kyphosis. These transitions progressively compress the LBV. Normally, this compression is circumvented via collateral pathways and "Blood finds a way". However, traversing these circuitous pathways comes at a cost and can result in delayed transit times and venous congestion. While it is possible that compression of the LBV in the setting of adequate collateral channels may fail to provoke any pathologic sequelae, we propose a phenomenon in which such compression in the setting of inadequate collateral circulation may lead to a state of pathologic venous congestion. This anatomic anomaly and its associated clinical features, if identified, can offer a new avenue for treatment options for some of the hitherto unexplained neurologic disorders.

Background: The lateral antebrachial cutaneous nerve (LACN) is the terminal sensory branch of the musculocutaneous nerve and is rarely entrapped or injured. This study describes the electrodiagnostic (EDX) findings and etiologies of LACN neuropathy.

Methods: This is a review of 49 patients with pain and/or paresthesia of the forearm who underwent EDX studies. The diagnosis of LACN neuropathy was based on clinical and sensory conduction abnormalities.

Results: The most common etiology of LACN neuropathy was iatrogenic injury in 30 (61.2%) patients, primarily due to biceps tendon repair at the elbow (11 [36.7%]) and phlebotomy (5 [16.7%]). Fifteen (30.6%) patients sustained a non-iatrogenic injury at the proximal forearm/elbow, consisting of six (60%) laceration injuries and five (33.3%) stretch injuries. Four (8.2%) patients comprised the "other" etiology category, including two mass lesions causing LACN compression. Pain, paresthesia, and/or numbness in the LACN distribution were reported in 33 (67.3%), 27 (55.1%), and 23 (46.9%) patients, respectively. Hypoesthesia was detected in 45 (91.8%) patients, and dysesthesia in 7 (14.3%). The sensory nerve action potentials (SNAPs) of the LACN on the symptomatic side were absent in 44 (89.8%) patients. Of the five patients whose SNAPs of the LACN were detected, all had a decreased amplitude, and two had increased sensory latency.

Conclusions: The most common etiology for LACN neuropathy in this series was iatrogenic injury; repair of biceps tendon at the elbow was the most frequent provoking cause. Protection of the LACN during surgical procedures at the elbow and forearm is vital to prevent iatrogenic injury.

We describe the case of a 63-year-old man with pontocerebellar hypoplasia without the claustrum (CL). The patient had a history of cerebral palsy, intelligent disability, cerebellar atrophy, and seizures since birth. At age 61, brain computed tomography (CT) revealed significant cerebellar and brainstem atrophy. At age 63, he was admitted to our hospital for aspiration pneumonia. Although he was treated with medications, including antibiotics, he died one month after admission. The autopsy revealed a total brain weight of 815 g, with the small-sized frontal lobe, cerebellum, and pons. The cross-section of the fourth ventricle had a slit-like appearance, rather than the typical diamond shape. In addition, bilateral CLs were not observed. Apart from CL, no other missing brain tissue or cells could be identified. Microscopic examinations disclosed neurofibrillary tangles in the hippocampus but not in the cortex; however, neither senile plaques nor Lewy bodies were detected. No acquired lesions, including cerebral infarction, hemorrhage, or necrosis, were noted. We pathologically diagnosed the patient with pontocerebellar hypoplasia without CL. As there have been no prior reports of pontocerebellar hypoplasia lacking CL in adults, this case may represent a new subtype. Congenital CL deficiency is likely associated with abnormalities in brain development. CL may play a role in seizure activity, and the loss of bilateral CLs does not necessarily result in immediate death. Further studies are needed to clarify the functions of CL.

Background: Working memory (WM) involves temporarily storing and manipulating information. Research on the impact of aging on WM has shown inconsistent results regarding the decline in visual and verbal WM, with a lack of studies on tactile WM. This study aimed to assess the effects of aging on WM across verbal, visuospatial, and tactile modalities using span tasks of forward (storage) and backward (manipulation) stages. Methods: A total of 130 participants, divided into four age groups of 20-29, 60-69, 70-79, and 80-89, completed the Digit, Visuospatial, and Tactual Spans. Performance was analyzed using a 3 (Task) × 4 (Group) × 2 (Stage) mixed design repeated measures ANOVA. Results: The analysis revealed significant main effects for modality (p < 0.001, η_p² = 0.15), age (p < 0.001, η_p² = 0.48), and stage (p < 0.001, η_p² = 0.30). Digit Span outperformed the other modalities, while Tactual Span showed the worst performance. Additionally, task performance declined with age, and the forward stage was superior to the backward stage. Interaction effects indicated that Digit Span was less affected by aging compared to the Visuospatial and Tactual Spans (p = 0.004, η_p² = 0.07). Post hoc analyses further revealed that the Digit Span consistently outperformed the other modalities in both stages, with more pronounced differences observed in the forward stage. Conclusions: Verbal WM is more resilient to aging compared to the other modalities while tactile WM declines with age in a manner similar to verbal and visuospatial WM, suggesting a modality-specific impact of aging on WM.

Background: Froin's syndrome (FS) is a rare entity with uncertain prevalence and prognosis, defined by a pathognomonic triad: cerebrospinal fluid (CSF) xanthochromia, elevated protein levels in the CSF, and hypercoagulated CSF, usually obtained through lumbar puncturing below the level of a partial or complete spinal block.

Methods: We conducted a comprehensive review of the literature on FS from its first description in 1903 to December 2023, utilizing PubMed and Google Scholar, and included two new cases from our clinical practice.

Results: We describe two patients who suffered from Froin's syndrome secondary to spinal abscesses. According to our review, FS is caused by neoplasia in 33% of cases, non-malignant mechanical causes in 27%, infections in 27%, non-infectious inflammatory processes in 6%, and vascular in 6%. The most prevalent symptoms are paraplegia/paraparesis (64%), back pain (38%), altered mental state and/or confusion (23%), sciatica (17%), headaches (17%), leg sensory defects (17%), and urinary retention (14%), and are thought to be linked with the underlying causes rather than the CSF characteristics. FS holds a poor prognosis: only 22% recuperate fully after treatment, 22% die due to the cause leading to FS, and 14% retain sequelae.

Conclusions: Xanthochromia and proteinorachia >500 mg/dL are not specific to any single pathological condition, but indicate defective CSF recirculation and spinal block, causing diffusive and/or inflammatory processes resulting in the hyperproteinosis and coagulation of the CSF. We reviewed the pathophysiology, etiologies, symptoms, outcomes, and workups of Froin's syndrome according to the existing medical literature.

Background/Objectives: Alzheimer's disease (AD) is an age-related degenerative brain disorder characterized by a progressive decline in cognitive function and memory. This study aimed to evaluate whether rutin hydrate (RH) has neuroprotective effects in an AD-like learning and memory impairment rat model induced by scopolamine (SCO). Methods: The rats were administered with RH (100 mg/kg) and SCO (1.5 mg/kg) and underwent behavioral tests, including the Morris water maze test, Y-maze test, and passive avoidance test, to evaluate their learning and memory abilities. Additionally, long-term potentiation (LTP) was induced to observe changes in the field excitatory postsynaptic potential (fEPSP) activity. Results: RH treatment attenuated the SCO-induced shortening of step-through latency in the passive avoidance (PA) test, increased the percentage of alternation in the Y-maze, and increased the time spent in the target zone in the Morris water maze (MWM). Moreover, RH increased the total activity of fEPSP following theta burst stimulation and attenuated the SCO-induced blockade of fEPSP. RH also ameliorated the SCO-induced decrease in the expression levels of the BDNF, TrkB, ERK, CREB, and Bcl-2 proteins and the increase in the Bax protein level in the rat hippocampus. This demonstrates that RH has beneficial neuroprotective effects in the brain, improving learning, memory, and synaptic plasticity in rats. Conclusions: Our results highlight the molecular and cellular mechanisms through which RH exerts its neuroprotective effects in the prevention and treatment of learning and memory deficit disorders. RH could potentially be used as a therapeutic strategy for the restoration of learning and memory function and the prevention of the progression of AD.

Background: The Frontal Assessment Battery (FAB), which is used to assess executive function, has been translated into several languages and shown to be valid and reliable. However, the validity and reliability of the Japanese version in patients with stroke are unknown. This study aimed to investigate the validity and reliability of the Japanese version of the FAB in patients with stroke.

Methods: The Japanese version of the FAB for dementia was modified and evaluated in 52 patients with stroke. FAB measurements were obtained twice over a 10-day period. Convergent validity was assessed using the Stroop Color Word Test (SCWT) and the Trail Making Test (TMT) part B. Internal consistency was measured using Cronbach's alpha (Cα). Test-retest evaluations were performed using intraclass correlation coefficient [ICC (2.1)] measurements, and limits of agreement (LOA) were calculated using the total FAB score.

Results: The mean total FAB score was 13.4 ± 2.8 points, the ICC (2.1) was 0.856, and Cα was 0.92. The total FAB score was correlated with SCWT scores for parts I through IV (r = 0.70 to 0.77) and the TMT score for part B (ρ = -0.53). The LOA were -1.7 to 2.9 points.

Conclusions: The Japanese version of the FAB had higher validity and reliability in patients with stroke.

Background/Objectives: Aging has been extensively studied, with a growing interest in memory impairment by a neurobiological approach. Mitochondrial dysfunction is a hallmark of aging, contributing to the aging phenotype; therefore, mitochondrial interventions seem fundamental. The diet is a physiological approximation for modifying mitochondria, which could impact the age-related phenotype. Methods: We studied two diets with low-carbohydrate and high-fat compositions, differing in the amount of protein and the fat type disposable-the atherogenic diet Cocoa (high protein/high saturated fat/high cholesterol) and the South Beach diet (very high-protein/high-unsaturated fat)-on oxidative stress, mitochondrial state, and hippocampus-dependent memory in 3-month-old Senescence-Accelerated Mouse Model (SAMP8) seed over 3 months to determine their pro- or anti-aging effects. Results: Despite its bad reputation, the Cocoa diet reduces the reactive oxygen species (ROS) content without impacting the energy state and hippocampus-dependent spatial acuity. In contrast to the beneficial impact proposed for the South Beach diet, it induced a pro-aging phenotype, increasing oxidative damage and the levels of NR2B subunit of the NMDA, impairing energy and spatial acuity. Surprisingly, despite the negative changes observed with both diets, this led to subtle memory impairment, suggesting the activation of compensatory mechanisms preventing more severe cognitive decline. Conclusions: Our results demonstrated that diets usually considered good could be detrimental to the onset of aging. Also, probably due to the brain plasticity of non-aged animals, they compensate for the damage, preventing a more aggravated phenotype. Nevertheless, these silent changes could predispose or increase the risk of suffering pathologies at advanced age.

Creutzfeldt-Jakob disease is a rare neurodegenerative and invariably fatal disease with a fulminant course once the first clinical symptoms emerge. Its incidence appears to be rising, although the increasing figures may be related to the improved diagnostic tools. Due to the highly variable clinical picture at onset, many specialty physicians should be aware of this disease and refer the patient to a neurologist for complete evaluation. The diagnostic criteria have been changed based on the considerable progress made in research on the pathogenesis and on the identification of reliable biomarkers. Moreover, accumulated knowledge on pathogenesis led to the identification of a series of possible therapeutic targets, although, given the low incidence and very rapid course, the evaluation of safety and efficacy of these therapeutic strategies is challenging.