The Clinical Features of Dissection of the Cervical Brain-Supplying Arteries.

BACKGROUND: Dissections of the cervical brain-supplying arteries are a leading cause of ischemic stroke in young adults, with an annual incidence of 2.5-3 / 100 000 for carotid artery dissection and 1-1.5 / 100 000 for vertebral artery dissection. It can be assumed that many cases go unreported. We present the clinical features here to help physicians diagnose this disease entity as rapidly as possible. METHODS: This review is based on pertinent publications retrieved by a selective search in PubMed. RESULTS: Spontaneous dissection of the internal carotid or vertebral artery is characterized by a hematoma in the vessel wall. It often arises in connection with minor injuries; underlying weakness of the arterial wall (possibly only temporary) may be a predisposing factor. Acute unilateral pain is the main presenting symptom. In internal carotid dissection, the site of the pain is temporal in 46% of cases, and frontal in 19%; in vertebral artery dissection, it is nuchal and occipital in 80%. Pain and local findings, such as Horner syndrome, are generally present from the beginning, while stroke may arise only after a latency of hours to days. If the diagnosis is made early with MRI, CT, or ultrasound, and anticoagulation or antiplatelet drugs can help prevent a stroke, yet none of these methods can detect all cases. Recurrent dissection is rare, except in patients with connective tissue diseases such as Ehlers-Danlos syndrome or fibromuscular dysplasia. Spontaneous dissection of the great vessels of the neck must be differentiated from aortic dissection spreading to the supra-aortic vessels and from traumatic dissection due to blunt or penetrating vascular trauma. CONCLUSION: Dissection of the cervical brain-supplying vessels is not always revealed by the imaging methods that are used to detect it. Stroke prevention thus depends on the physician's being aware of the symptoms and signs of this disease entity, so that early diagnosis can be followed by appropriate treatment.

FabryScan: a screening tool for early detection of Fabry disease.

Fabry disease, an X-linked lipid storage disorder, is associated early morbidity and mortality. Since enzyme replacement therapy is available, accurate detection of unrecognized cases is important. Characteristic early symptoms are recurrent episodes of burning and lancinating pain in the distal extremities associated with small fiber neuropathy. The aim was to develop and validate an easy diagnostic questionnaire in combination with three simple bedside tests, the "FabryScan", for the detection of Fabry disease in patients with chronic extremity pain. Questions related to relevant clinical characteristics of Fabry disease (mainly related to pain) were compiled by Fabry specialists and pain experts. Furthermore, three bedside tests assessing sensory small and large fiber function were established. The provisional version was tested in a prospective multicenter trial of 138 patients with chronic extremity pain due to Fabry disease (n = 55), painful polyneuropathy (n = 40), and rheumatoid arthritis (n = 43). Identification of the most discriminant combinations of items for Fabry disease and their calculation of sensitivity and specificity were based on multivariate analyses. We retained only 10 questions and three bedside tests for the final version of the FabryScan. A cut-off score of 12/33 (corresponding to the number of positive points) resulted in a high proportion of correctly identified patients (76 %) with a sensitivity of 88 % and a specificity of 87 %. The FabryScan is a combination of a brief and simple questionnaire with three simple bedside tests with good discriminative value for the identification of Fabry patients in patients with chronic extremity pain.

Department-related tasks and organ-targeted therapy in Fabry disease: an interdisciplinary challenge.

Fabry disease is a rare X-linked storage disorder leading to an accumulation of globotriaosylceramides in all cells carrying lysosomes. As the accumulation occurs in most organs, different medical specialties are involved in the diagnostics and therapy of Fabry disease. With this review of the 3 main specialties (cardiology, nephrology, and neurology) and, in addition, the adjacent specialties (ophthalmology and dermatology), we aim to discuss the division-related responsibilities and want to suggest an organ-related additional therapy besides enzyme replacement therapy.

Evaluation of symptom heterogeneity in neuropathic pain using assessments of sensory functions.

Classification of neuropathic pain has been based on disease entities, anatomical localization, or histological observations. Over the past decade, there has been an explosion in our understanding of the basic mechanisms of neuropathic pain. The exciting advances in basic science are paralleled by the recognition from clinical investigations that neuropathic pain is not a monolithic entity, but instead presents as a composite of pain and other sensory symptoms. Attempts are under way to supplement the traditional classification with a classification that links pain and sensory symptoms with neurobiological mechanisms. This mechanism- or symptom-based classification takes both negative and positive sensory symptoms into account. By using a battery of several standardized quantitative sensory tests, the characteristic profile of sensory symptoms can be elucidated in each patient. Moreover, in questionnaires the verbal descriptors can depict the quality and intensity of the individual pain. The approach of classifying and subgrouping patients with neuropathic pain on the basis of symptoms or signs opens up new possibilities for stratifying patients in clinical trials. First, in clinical proof-of-concept trials the study population can be enriched prospectively on the basis of entry criteria defined a priori. This enrichment with patients who potentially require a specific treatment should increase the likelihood for positive trial outcomes. Second, in clinical practice it becomes possible to establish an individualized therapy--that is, to identify the particular patients who require a specific treatment option.

Time delay and partial coherence analyses to identify cortical connectivities.

Recently it has been demonstrated by Albo that partial coherence analysis is sensitive to signal to noise ratio (SNR) and that it will always identify the signal with the highest SNR among the three signals as the main (driving) influence. We propose to use time delay analysis in parallel to partial coherence analysis to identify the connectivities between the multivariate time series. Both are applied to a theoretical model (used by Albo) to analyse the connections introduced in the model. Time delay analysis identifies the connections correctly. We also apply these analyses to the electroencephalogram (EEG) and electromyogram of essential tremor patients and EEG of normal subjects while bimanually tapping their index fingers. Biologically plausible cortico-muscular and cortico-cortical connections are identified by these methods.