Anatomy of the corticospinal tract and its importance in the resection of pontine cavernomas
DOI:
https://doi.org/10.59156/gdz6zz18Keywords:
Corticospinal, Dissection, Pontine cavernoma, TractographyAbstract
Background: surgical resection of pontine cavernomas presents a challenge due to the density of critical neural structures in this region, including the corticospinal tract.
Objectives: to provide a detailed description of the corticospinal tract's course using dissections and tractography, in order to define anatomical parameters that allow for the avoidance of injury to this tract during pontine surgery.
Methods: tractography was performed using DSI Studio software on 1065 brains from healthy subjects belonging to the Human Connectome Project to illustrate the corticospinal tract. Six brainstems were designed using microsurgical instruments and the Klingler method.
Results: in the tractography, the TCE fibers were found ventrally related to the superficial layer of the ESTP fibers and dorsally to the EPTP, separated from the pontine tegmentum by the LM. Relationships of the TCE in dissections: ventrally, 1.1-2 mm of the ESTP was resected. Laterally, the EMTP was identified, and a resection was performed to the apparent origin of CN V, located 3.9-4.1 mm from the TCE. Deep dissection allowed the spinal trigeminal nucleus to be located 10.2-12.4 mm deep. Dorsally, the EPTP was identified, separating the pyramidal fibers from the LM.
Conclusion: the results obtained allow for the definition of specific anatomical parameters as key surgical landmarks. The arrangement of transverse fibers can be used during the planning and execution of pontine surgical approaches.
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