Introduction: The wide range of anatomical variability of the structures of the middle cranial fossa and the lack of reliable surgical landmarks contribute to a high level of complications in the surgical treatment of vestibular schwannomas. We hypothesized that the cranial phenotype influences the shape of the middle cranial fossa, the orientation of the pyramid of the temporal bone, and the relative topography of the internal acoustic canal.
Materials and Methods: The skull base structures were studied on 54 embalmed cadavers and 60 MR images of the head and neck by photo modeling, dissection, and 3D analysis techniques. By the value of the cranial index, all specimens were subdivided into dolichocephalic, mesocephalic, and brachycephalic groups for comparison of variables.
Results: The length of the superior border of the temporal pyramid, the apex to squama distance, and the width of the middle cranial fossa all peaked in the brachycephalic group. The value of the angle between the superior border of the pyramid and the axis of the acoustic canal varied from 33 to 58 º; it peaked in the dolichocephalic group and showed its smaller value in the brachycephalic one. The pyramid to squama angle had reversed distribution and dominated in the brachycephalic group.
Conclusions: The cranial phenotype influences the shape of the middle cranial fossa, temporal pyramid, and internal acoustic canal. Presented in this paper data help specialists operating on the vestibular schwannoma to localize the internal acoustic canal based on the individual shape of a skull.
Introduction: We hypothesized that the cranial phenotype influences the shape of the posterior cranial fossa and the relative position of the sigmoid sinus. Materials and Methods: The topography of the sigmoid sinus was studied on 26 magnetic resonance venograms and 35 embalmed cadavers by morphometric analysis, dissection, and photo modeling techniques. Results: The data show that the transverse diameter of the posterior cranial fossa correlates positively with the laterolateral diameter of the skull. The majority of cases with the low-anterior position of the sigmoid sinus were recorded in the brachycephalic group (82%); while the high-posterior localization of the sigmoid sinus was typical for the dolichocephalic patients (63%). Conclusion: The shape of the skull reflects the morphology of the posterior cranial fossa and influences the topographic characteristics of the sigmoid sinus that must be considered in the selection of surgical approach to the inner ear and pontocerebellar angle.
Introduction
We hypothesized that the cranial phenotype influences the shape of the posterior cranial fossa and the relative position of the sigmoid sinus.
Materials and methods
The topography of the sigmoid sinus was studied on 26 magnetic resonance venograms and 35 embalmed cadavers by morphometric analysis, dissection, and photo modeling techniques.
Results
The data show that the transverse diameter of the posterior cranial fossa correlates positively with the laterolateral diameter of the skull. The majority of cases with the low-anterior position of the sigmoid sinus were recorded in the brachycephalic group (82%), while the high-posterior localization of the sigmoid sinus was typical for the dolichocephalic patients (63%). The results of the ANOVA test confirm the significance of differences.
Conclusions
The shape of the skull reflects the morphology of the posterior cranial fossa and influences the topographic characteristics of the sigmoid sinus that must be considered in the selection of surgical approach to the inner ear and pontocerebellar angle.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.