Meningeal architecture of Meckel's Cave and its surgical implications: A study using epoxy sheet plastination and three-dimensional reconstruction.

Background: The architecture of Meckel's Cave (MC) dural walls and their associations with neighboring structures remain subjects of debate. Few studies have explored the thickness of the MC dural walls. The primary aim of this study was to elucidate the detailed meningeal architecture of MC and its relationship with the internal carotid artery, using sheet plastination technology to analyze the potential spreading pathways of tumors through the medial wall.

Methods: Ultrathin plastinated slices were prepared and examined in coronal, sagittal, and transverse planes. Three-dimensional reconstructions were generated to analyze the composition of MC's dural walls and their association with the trigeminal ganglion (TG), its nerve roots and branches, and the alignment of the internal carotid artery (ICA). Particular attention was given to the medial wall of MC and the variations in ICA trajectories.

Results: The study identified distinct regions within MC, highlighting the composition of the superolateral, medial, and inferior walls. The arachnoid mater was shown to enclose the trigeminal rootlets and contribute to the formation of the perineurium in motor roots. Four different ICA trajectories in relation to the medial wall were classified, each influencing the configuration of the quadrangular space. These variations were found to have implications for surgical planning, particularly in endoscopic endonasal approaches. The study also demonstrated key differences in the structural relationships affecting invasive tumor growth pathways.

Conclusions: The findings of this study provide new insights into the microanatomy of MC and its relationships with the TG and ICA. These results offer a foundational basis for surgical planning and may help refine strategies for accessing lesions in this complex anatomical region.