Vesper Fe Marie Llaneza Ramos1, Elaine Considine1, Barbara I Karp2, Codrin Lungu3, Katharine Alter4, Mark Hallett1. 1. Human Motor Control Section, National Institutes of Health, Bethesda, MD. 2. CNS, IRB, National Institutes of Health, Bethesda, MD. 3. Office of the Clinical Director, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD. 4. Functional and Applied Biomechanics Section, Rehabilitation Medicine Department, National Institutes of Health, Bethesda, MD and Mount Washington Pediatric Hospital, Washington, DC.
Abstract
BACKGROUND: Diaphragmatic myoclonus is a rare disorder of repetitive diaphragmatic contractions, acknowledged to be a spectrum that includes psychogenic features. Electromyography has been the diagnostic tool most commonly used in the literature. METHODS: To test if we could perform a noninvasive technique to delineate the diaphragm as the source of abnormal movements and demonstrate distractibility and entrainability, we used B-mode ultrasound in a patient with diaphragmatic myoclonus. RESULTS: Ultrasound imaging clearly delineated the diaphragm as the source of her abdominal movements. We were able to demonstrate entrainability of the diaphragm to hand tapping to a prescribed rhythm set by examiner. CONCLUSION: We recommend the use of ultrasound as a noninvasive, convenient diagnostic tool for further studies of diaphragmatic myoclonus. We agree with previous findings that diaphragmatic myoclonus may be a functional movement disorder, as evidenced by distractibility and entrainability demonstrated on real-time video with ultrasonography.
BACKGROUND:Diaphragmatic myoclonus is a rare disorder of repetitive diaphragmatic contractions, acknowledged to be a spectrum that includes psychogenic features. Electromyography has been the diagnostic tool most commonly used in the literature. METHODS: To test if we could perform a noninvasive technique to delineate the diaphragm as the source of abnormal movements and demonstrate distractibility and entrainability, we used B-mode ultrasound in a patient with diaphragmatic myoclonus. RESULTS: Ultrasound imaging clearly delineated the diaphragm as the source of her abdominal movements. We were able to demonstrate entrainability of the diaphragm to hand tapping to a prescribed rhythm set by examiner. CONCLUSION: We recommend the use of ultrasound as a noninvasive, convenient diagnostic tool for further studies of diaphragmatic myoclonus. We agree with previous findings that diaphragmatic myoclonus may be a functional movement disorder, as evidenced by distractibility and entrainability demonstrated on real-time video with ultrasonography.
Entities:
Keywords:
conversion; motor control; myoclonus; ultrasound