Diagnosis and classification of blepharospasm: Recommendations based on empirical evidence

• Type of Material: Article
• Authors: Gamze Kilic-Berkmen, Emory University; Giovanni Defazio, University of Cagliari; Mark Hallett, National Institute of Neurological Disorders and Stroke; Alfredo Berardelli, Sapienza University Rome; Gina Ferrazzano, Sapienza University Rome; Daniele Belvisi, Sapienza University Rome; Christine Klein, University of Lubeck; Tobias Baumer, University of Lubeck; Anne Weissbach, University of Lubeck; Joel S. Perlmutter, Washington University in St. Louis; Jeanne Feuerstein, University of Colorado; Hyder Jinnah, Emory University
• Language: English
• Date: 2022-08-15
• Publisher: ELSEVIER
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2022 Elsevier B.V. All rights reserved.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.jns.2022.120319
• Title of Journal or Parent Work: JOURNAL OF THE NEUROLOGICAL SCIENCES
• Volume: 439
• Start Page: 120319
• End Page: 120319
• Grant/Funding Information: This work was supported by grants to The Dystonia Coalition (NS065701, TR001456, NS116025) which is part of the National Institutes of Health (NIH) Rare Disease Clinical Research Network (RDCRN), supported by the Office of Rare Diseases Research (ORDR) at the National Center for Advancing Translational Science (NCATS), and the National Institute of Neurological Diseases and Stroke (NINDS).
• Keywords: Neurosciences; Craniofacial dystonia; Science & Technology; ONSET; Life Sciences & Biomedicine; Meige syndrome; Neurosciences & Neurology; RISK; Clinical Neurology; SPREAD; ISOLATED FOCAL DYSTONIA; Blepharospasm
• Research Categories: Biology, Neuroscience

Abstract

Background: Blepharospasm is one of the most common subtypes of dystonia, and often spreads to other body regions. Despite published guidelines, the approach to diagnosis and classification of affected body regions varies among clinicians. Objective: To delineate the clinical features used by movement disorder specialists in the diagnosis and classification of blepharospasm according to body regions affected, and to develop recommendations for a more consistent approach. Methods: Cross-sectional data for subjects diagnosed with all types of isolated dystonia were acquired from the Dystonia Coalition, an international, multicenter collaborative research network. Data were evaluated to determine how examinations recorded by movement disorder specialists were used to classify blepharospasm as focal, segmental, or multifocal. Results: Among all 3222 participants with isolated dystonia, 210 (6.5%) had a diagnosis of focal blepharospasm. Among these 210 participants, 34 (16.2%) had dystonia outside of upper face region. Factors such as dystonia severity across different body regions and number of body regions affected influenced the classification of blepharospasm as focal, segmental, or multifocal. Conclusions: Although focal blepharospasm is the second most common type of dystonia, a high percentage of individuals given this diagnosis had dystonia outside of the eye/upper face region. These findings are not consistent with existing guidelines for the diagnosis and classification of focal blepharospasm, and point to the need for more specific guidelines for more consistent application of existing recommendations for diagnosis and classification.