TY - JOUR
T1 - Spatial clustering analysis in neuroanatomy
T2 - Applications of different approaches to motor nerve fiber distribution
AU - Prodanov, Dimiter
AU - Nagelkerke, Nico
AU - Marani, Enrico
N1 - Funding Information:
D. Prodanov was funded by a fellowship from the International Brain Research Organization. Initial research work was financially supported by the NeuralPRO project, EU Framework 5 Program, contract No HPRN-CT-2000-00030 - Neural Prostheses.
PY - 2007/2/15
Y1 - 2007/2/15
N2 - Spatial organization of the nerve fibers in the peripheral nerves may be important for the studies of axonal regeneration, the degenerative nerve diseases and the construction of interfaces with peripheral nerves, such as nerve prostheses. Functional topography of motor axons related to the gastrocnemius muscle was revealed in the ventral spinal roots by retrograde tracing. Gastrocnemius muscles of adult rats were injected with the tracer Fluoro-Gold. After 3 days of survival the animals were sacrificed and their ventral roots were harvested, sectioned, and imaged on a fluorescence microscope. Maps of the traced fibers were automatically analyzed using a novel approach, local spatial clustering statistics, that tested for occurrences of clusters of motor fibers and visualized them. Thresholds indicating the presence of clustering at various scales of observation were computed based on series of Monte Carlo simulations of random spatial point patterns. Clusters were visualized by kernel interpolation. The approach was tested on simulated data and subsequently applied to the motor fiber maps in the ventral roots. Results revealed clustering of the motor fibers innervating the gastrocnemius muscle at the level of the L6 ventral spinal root. The analysis was validated using Voronoi tessellation and nearest neighbor analysis.
AB - Spatial organization of the nerve fibers in the peripheral nerves may be important for the studies of axonal regeneration, the degenerative nerve diseases and the construction of interfaces with peripheral nerves, such as nerve prostheses. Functional topography of motor axons related to the gastrocnemius muscle was revealed in the ventral spinal roots by retrograde tracing. Gastrocnemius muscles of adult rats were injected with the tracer Fluoro-Gold. After 3 days of survival the animals were sacrificed and their ventral roots were harvested, sectioned, and imaged on a fluorescence microscope. Maps of the traced fibers were automatically analyzed using a novel approach, local spatial clustering statistics, that tested for occurrences of clusters of motor fibers and visualized them. Thresholds indicating the presence of clustering at various scales of observation were computed based on series of Monte Carlo simulations of random spatial point patterns. Clusters were visualized by kernel interpolation. The approach was tested on simulated data and subsequently applied to the motor fiber maps in the ventral roots. Results revealed clustering of the motor fibers innervating the gastrocnemius muscle at the level of the L6 ventral spinal root. The analysis was validated using Voronoi tessellation and nearest neighbor analysis.
KW - ImageJ
KW - Nearest neighbor
KW - Nerve topography
KW - Point process
KW - Quadrate count
KW - Retrograde tracing
KW - Spatial point pattern
KW - Voronoi tessellation
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U2 - 10.1016/j.jneumeth.2006.08.017
DO - 10.1016/j.jneumeth.2006.08.017
M3 - Article
C2 - 17049615
AN - SCOPUS:33846280527
SN - 0165-0270
VL - 160
SP - 93
EP - 108
JO - Journal of Neuroscience Methods
JF - Journal of Neuroscience Methods
IS - 1
ER -