1. A look inside the nerve - Morphology of nerve fascicles in healthy controls and patients with polyneuropathy
- Author
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Tim W. Rattay, Hubertus Axer, Natalie Winter, Florian Härtig, Alexander Grimm, Eva Auffenberg, Marilin Koch, and Nele Maria Dammeier
- Subjects
Adult ,Male ,Popliteal fossa ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Polyneuropathies ,0302 clinical medicine ,Physiology (medical) ,Medicine ,Humans ,ddc:610 ,Ulnar nerve ,Tibial nerve ,diagnostic imaging [Peroneal Nerve] ,Radial nerve ,Ulnar Nerve ,Ultrasonography ,medicine.diagnostic_test ,business.industry ,methods [Ultrasonography] ,Peroneal Nerve ,Anatomy ,Fascicle ,Middle Aged ,medicine.disease ,diagnostic imaging [Median Nerve] ,Sensory Systems ,Median nerve ,Healthy Volunteers ,Median Nerve ,medicine.anatomical_structure ,Neurology ,diagnostic imaging [Polyneuropathies] ,diagnostic imaging [Ulnar Nerve] ,Nerve conduction study ,Female ,Neurology (clinical) ,business ,Polyneuropathy ,030217 neurology & neurosurgery - Abstract
Objective Polyneuropathies are increasingly analyzed by ultrasound. Summarizing, diffuse enlargement is typical in Charcot-Marie Tooth type 1 (CMT1a), regional enlargement occurs in inflammatory neuropathies. However, a distinction of subtypes is still challenging. Therefore, this study focused on fascicle size and pattern in controls and distinct neuropathies. Methods Cross-sectional area (CSA) of the median, ulnar and peroneal nerve (MN, UN, PN) was measured at predefined landmarks in 50 healthy controls, 15 CMT1a and 13 MMN patients. Additionally, largest fascicle size and number of visible fascicles was obtained at the mid-upper arm cross-section of the MN and UN and in the popliteal fossa cross-section of the PN. Results Cut-off normal values for fascicle size in the MN, UN and PN were defined ( 2 , 2 and 2 ). In CMT1a CSA and fascicle values are significantly enlarged in all nerves, while in MMN CSA and fascicles are regionally enlarged with predominance in the upper arm nerves. The ratio of enlarged fascicles and all fascicles was significantly increased in CMT1a (>50%) in all nerves (p 20%), representing differential fascicle enlargement (enlarged and normal fascicles at the same location) sparing the peroneal nerve (regional fascicle enlargement). Based on these findings distinct fascicle patterns were defined. Conclusion Normal values for fascicle size could be evaluated; while CMT1a features diffuse fascicle enlargement, MMN shows regional and differential predominance with enlarged fascicles as single pathology. Significance Pattern analysis of fascicles might facilitate distinction of several otherwise similar neuropathies.
- Published
- 2017