Limb Shaking as a Manifestation of Low-flow Transient Ischemic Attacks

Understanding Functional Neurological Disorder: Recent Insights and Diagnostic Challenges

Functional neurological disorder (FND), formerly called conversion disorder, is a condition characterized by neurological symptoms that lack an identifiable organic purpose. These signs, which can consist of motor, sensory, or cognitive disturbances, are not deliberately produced and often vary in severity. Its diagnosis is predicated on clinical evaluation and the exclusion of other medical or psychiatric situations. Its treatment typically involves a multidisciplinary technique addressing each of the neurological symptoms and underlying psychological factors via a mixture of medical management, psychotherapy, and supportive interventions. Recent advances in neuroimaging and a deeper exploration of its epidemiology, pathophysiology, and clinical presentation have shed new light on this disorder. This paper synthesizes the current knowledge on FND, focusing on its epidemiology and underlying mechanisms, neuroimaging insights, and the differentiation of FND from feigning or malingering. This review highlights the phenotypic heterogeneity of FND and the diagnostic challenges it presents. It also discusses the significant role of neuroimaging in unraveling the complex neural underpinnings of FND and its potential in predicting treatment response. This paper underscores the importance of a nuanced understanding of FND in informing clinical practice and guiding future research. With advancements in neuroimaging techniques and growing recognition of the disorder's multifaceted nature, the paper suggests a promising trajectory toward more effective, personalized treatment strategies and a better overall understanding of the disorder.

Limb-Shaking Transient Ischemic Attacks in Patients with Carotid Occlusion or Stenosis: A Systematic Review and Individual Patient Data Meta-Analysis

BACKGROUND

Limb-shaking transient ischemic attack (LSTIA) is a rare neurological condition which presents with involuntary jerky movements of the arm or leg, often because of carotid stenosis or occlusion. Due to the rarity of the condition, the epidemiology of LSTIA is poorly understood and the disease is frequently misdiagnosed. There is no standard treatment to date. The purpose of this study was to provide an overview of the epidemiology of LSTIA and its current treatment options.

METHODS

Embase, MEDLINE, Web of Science, Cochrane Central Register of Controlled Trials for randomized controlled trials, and Google Scholar were searched from database inception to December 30, 2023 for articles containing information on the epidemiology and treatment of LSTIA. An individual patient data meta-analysis (IPD-MA) was performed using data extracted from the included articles. Inclusion criteria were description of both the epidemiology and treatment of LSTIA in patients over the age of 18 with carotid stenosis/occlusion, confirmed by radiographic imaging. Exclusion criteria were studies focusing on pediatrics, no epidemiological data, internal carotid artery (ICA) stenosis/occlusion not radiologically confirmed, full text unavailable, full text not in English or Dutch, and non-original articles.

RESULTS

Of the 8,855 articles screened, 55 articles containing 251 patients were included. Fifty articles harboring 81 patients were included in the IPD-MA, and 7 articles harboring 187 patients were included in the cohort analysis. The results of the IPD-MA showed that LSTIA was caused by unilateral ICA stenosis/occlusion in 29 patients (36%) and most often from bilateral ICA stenosis/occlusion in 52 patients (64%). Limb-shaking was unilateral in 66 patients (83%) and was accompanied by weakness in 27 patients (33%). The intervention with the highest success rate was endovascular intervention (carotid stenting or balloon angioplasty), as all 10 patients remained asymptomatic after treatment. The cohort analysis showed that LSTIA can be caused by both unilateral and bilateral carotid stenosis or occlusion. The prevalence within cohorts of TIA patients of LSTIA varied considerably from 3.5 to 29%.

CONCLUSION

A large international clinical registry is warranted to gain a better understanding of the epidemiology of LSTIA. There is insufficient evidence available to suggest a standard treatment.

Limb-shaking TIA in Moyamoya angiopathy

BACKGROUND

Limb shaking TIA(LS-TIA) is an rare manifestation seen in high grade steno-occlusive carotid disease. LS-TIA is rarely recognized as a presenting manifestation of MMA and has never been previously studied prospectively in MMA cohort.

METHODS

Of 104 cases of MMA collected in our Indian center in last 4 years, 5 new patients had LS-TIA. MMA was diagnosed by MR angiography and LS-TIA was confirmed by three different neurologist by detailed scrutiny of history, neurological examination and EEG-recording (to rule out seizure). Seven previously reported cases of LS-TIA in MMA were retrieved by literature search in PubMed using keywords "Moyamoya" AND "Limb shaking TIA", "Moyamoya" AND "Limb shaking". Subsequently all data were analyzed and compared using descriptive statistics.

RESULTS

Analysis of our 5 cases and those 7 found in the literature showed mean age at the time of diagnosis of MMA was 12.2 ± 8.9(Mean ± S.D.) years in our cases and 32.7 ± 13.6 years in previous cases. The commonest precipitating factors included prolonged crying and hyperventilation(3 of 5 our cases each) and exercise (3 of 7 previous cases). CT-perfusion demonstrated frontal white matter hypoperfusion in 2 of our 5 cases, corroborative with fronto-parietal hypoperfusion in previous cases. Medical management showed decreased symptoms in 4 of our 5 cases in a follow-up of 15.8 ± 11.6 months, while all previous patients had underwent revascularization surgery with resolution of symptoms.

CONCLUSION

LS-TIA in MMA may not be so uncommon, especially in children. Early recognition is imperative to avoid future catastrophe. Steno-occlusive posterior circulation lesions might be an independent predictor of development of LS-TIA in MMA. In a resource-limited setting, careful avoidance of triggers and anti-platelet therapy can lead to decreased symptomatology of LS-TIA in MMA.

Post-stroke Movement Disorders: Clinical Spectrum, Pathogenesis, and Management

Involuntary movements develop after 1-4% of strokes and they have been reported in patients with ischemic and hemorrhagic strokes affecting the basal ganglia, thalamus, and/or their connections. Hemichorea-hemiballism is the most common movement disorder following a stroke in adults while dystonia is most common in children. Tremor, myoclonus, asterixis, stereotypies, and vascular parkinsonism are other movement disorders seen following stroke. Some of them occur immediately after acute stroke, some can develop later, and others may have delayed onset progressive course. Proposed pathophysiological mechanisms include neuronal plasticity, functional diaschisis, and age-related differences in brain metabolism. There are no guidelines regarding the management of post-stroke movement disorders, mainly because of their heterogeneity.

Cerebral misery perfusion due to carotid occlusive disease

Purpose

Cerebral misery perfusion (CMP) is a condition where cerebral autoregulatory capacity is exhausted, and cerebral blood supply in insufficient to meet metabolic demand.

We present an educational review of this important condition, which has a range of clinical manifestations.

Method

A non-systematic review of published literature was undertaken on CMP and major cerebral artery occlusive disease, using Pubmed and Sciencedirect.

Findings

Patients with CMP may present with strokes in watershed territories, collapses and transient ischaemic attacks or episodic movements associated with an orthostatic component. While positron emission tomography is the gold standard investigation for misery perfusion, advanced MRI is being increasingly used as an alternative investigation modality. The presence of CMP increases the risk of strokes. In addition to the devastating effect of stroke, there is accumulating evidence of impaired cognition and quality of life with carotid occlusive disease (COD) and misery perfusion. The evidence for revascularisation in the setting of complete carotid occlusion is weak. Medical management constitutes careful blood pressure management while addressing other vascular risk factors.

Discussion

The evidence for the management of patients with COD and CMP is discussed, together with recommendations based on our local experience. In this review, we focus on misery perfusion due to COD.

Conclusion

Patients with CMP and COD may present with a wide-ranging clinical phenotype and therefore to many specialties. Early identification of patients with misery perfusion may allow appropriate management and focus on strategies to maintain or improve cerebral blood flow, while avoiding potentially harmful treatment.

Atypical presentations of acute cerebrovascular syndromes

Correct diagnosis of acute stroke is of paramount importance to clinicians to enable selection of correct treatments and to ensure prevention of acute complications, including recurrent stroke. Timely diagnosis can be difficult in some cases because patients with acute stroke can present with atypical or uncommon symptoms that suggest another cause altogether. Publications on these patients suggest that the following strategies could help to reduce misdiagnosis. First, clinicians should suspect stroke in any patient with abrupt onset of neurological symptoms. Second, clinicians should be aware that some patients will initially present with various uncommon and atypical stroke symptoms. Third, a complete and systematic neurological examination should be routinely done in patients presenting with acute neurological symptoms because this might shed light on the true nature of the problem. Finally, clinicians should be aware that even with the most sophisticated neuroimaging tests, stroke might be missed in the early hours after the event.