Sensory Neurons of the Human Brachial Plexus: A Quantitative Study Employing Optical Fractionation and In-Vivo Volumetric Magnetic Resonance Imaging.
2012 (English)In: Neurosurgery, ISSN 0148-396X, E-ISSN 1524-4040, Vol. 70, no 5, 1183-1194 p.Article in journal (Refereed) Published
BACKGROUND: Extensive neuron death following peripheral nerve trauma is implicated in poor sensory recovery. Translational research for experimentally proven neuroprotective drugs requires knowledge of the numbers and distribution of sensory neurons in the human upper limb, and a novel non-invasive clinical measure of neuron loss. OBJECTIVE: To compare optical fractionation and volumetric MRI of dorsal root ganglia (DRG) in histological quantification and objective clinical assessment of human brachial plexus sensory neurons. METHODS: Bilateral C5-T1 DRG were harvested from 5 human cadavers for stereological volume measurement and sensory neuron counts (optical fractionator). MRI scans were obtained from 14 normal volunteers for volumetric analysis of C5-T1 DRG. RESULTS: 425,409 (SD 15,596) sensory neurons innervate the brachial plexus with a significant difference in neuron counts and DRG volume between segmental levels (p<0.0001), with C7 ganglion containing the most. DRG volume correlated with neuron counts (r=0.75, p<.001). Vertebral artery pulsation hindered C5&6 imaging, yet high resolution MRI of C7, C8 and T1 DRG permitted unbiased volume measurement. In accord with histological analysis, MRI confirmed a significant difference between C7, C8 and T1 DRG volume (p<.001), inter-individual variability (COV 15.3%), and sex differences (p=.04). Slight right-left (R/L) sided disparity in neuron counts (2.5%, p=.04) was possibly related to hand dominance, but no significant volume disparity existed. CONCLUSION: Neuron counts for the human brachial plexus are presented. These correlate with histological DRG volumes and concur with volumetric MRI results in human volunteers. Volumetric MRI of C7-T1 DRG is a legitimate non-invasive proxy measure of sensory neurons for clinical study.
Place, publisher, year, edition, pages
Philadelphia: Lippincott Williams & Wilkins, 2012. Vol. 70, no 5, 1183-1194 p.
Dorsal root ganglia, Human, Magnetic resonance imaging, Nerve trauma, Neuroprotection, Sensory neuron death
IdentifiersURN: urn:nbn:se:umu:diva-53238DOI: 10.1227/NEU.0b013e318241ace1ISI: 000303390400038PubMedID: 22095219OAI: oai:DiVA.org:umu-53238DiVA: diva2:510872