TY - JOUR
TI - The Topography of the Frontal Terminations of the Uncinate Fasciculus
Revisited Through Focused Fiber Dissections: Shedding Light on a Current
Controversy and Introducing the Insular Apex as a Key Anatomoclinical
Area
AU - Liakos, Faidon
AU - Komaitis, Spyridon
AU - Drosos, Evangelos and
AU - Neromyliotis, Eleftherios
AU - Skandalakis, Georgios P.
AU - Gerogiannis,
AU - Apostolos I.
AU - V. Kalyvas, Aristotelis
AU - Troupis, Theodore and
AU - Stranjalis, George
AU - Koutsarnakis, Christos
JO - World Neurosurgery
PY - 2021
VL - 152
TODO - null
SP - E625-E634
PB - EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC
SN - 1878-8750
TODO - 10.1016/j.wneu.2021.06.012
TODO - Axonal connectivity; Brain anatomy; Fiber dissection technique; Insula;
Occipitofrontal fasciculus; Orbitofrontal cortex; Uncinate fasciculus
TODO - BACKGROUND: Recent studies advocate a connectivity pattern wider than
previously believed of the uncinate fasciculus that extends to the
ventrolateral and dorsolateral prefrontal cortices. These new percepts
on the connectivity of the tract suggest a more expansive role for the
ncinate fasciculus. Our aim was to shed light on this controversy
through fiber dissections. METHODS: Twenty normal adult human
formalin-fixed cerebral hemispheres were used. Focused dissections on
the insular, orbitofrontal, ventromedial, ventrolateral, and
dorsolateral prefrontal areas were performed to record the topography of
the frontal terminations of the uncinate fasciculus. RESULTS: Three
discrete fiber layers were consistently disclosed: the first layer was
recorded to terminate at the posterior orbital gyrus and pars orbitalis,
the second layer at the posterior two thirds of the gyrus rectus, and
the last layer at the posterior one third of the paraolfactory gyrus.
The insular apex was documented as a crucial landmark regarding the
topographic differentiation of the uncinate and occipitofrontal
fasciculi (i.e., fibers that travel ventrally belong to the uncinate
fasciculus whereas those traveling dorsally are occipitofrontal fibers).
CONCLUSIONS: The frontal terminations of the uncinate fasciculus were
consistently documented to project to the posterior orbitofrontal area.
The area of the insular apex is introduced for the first time as a
crucial surface landmark to effectively distinguish the stems of the
uncinate and occipitofrontal fasciculi. This finding could refine the
spatial resolution of awake subcortical mapping, especially for insular
lesions, and improve the accuracy of in vivo diffusion tensor imaging
protocols.
ER -