ArticleNeurosurgical review2023
Anatomical study of the mastoid foramina and mastoid emissary veins: classification and application to localizing the sigmoid sinus.
Article in Neurosurgical review, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers, 1 of them a synthesis that pooled it.
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Who cites it
5 citing papers in PubMed, 1 synthesis or guideline pooled it, 7 citations in OpenAlex.
- A systematic review with meta-analysis of the olfactory fossa anatomy: Implications for anterior skull base approaches.Neurosurgical review · 2026Pooled it
- Anatomical Variability of the Transverse and Sigmoid Sinus Grooves: Implications for Skull Base Surgery.Journal of neurological surgery. Part B, Skull base · 2026Article
- The enigmatic occipital emissary vein, foramina, and canals: anatomical study with application to skull base surgery.Neurosurgical review · 2026Article
- Mastoid emissary vein, mastoid emissary foramen, and mastoid emissary canal: anatomy, variability, imaging, and clinical implications.Surgical and radiologic anatomy : SRA · 2026Review
- Bony prominence and variations of the transverse sinus groove: novel anatomical findings in relation to sinus pathologies.Neurosurgical review · 2024Article
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Authors and funding
7 authors at 5 institutions in 5 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The mastoid foramen (MF) is located on the mastoid process of the temporal bone, adjacent to the occipitomastoid suture or the parietomastoid suture, and contains the mastoid emissary vein (MEV). In retrosigmoid craniotomy, the MEV has been used to localize the position of the sigmoid sinus and, thus, the placement of the initial burr hole. Therefore, this study aimed to examine the exact location and variants of the MF and MEV to determine if their use in localizing the sigmoid sinus is reasonable. The sample in this study comprised 22 adult dried skulls (44 sides). MF were identified and classified into five types based on location, prevalence, whether they communicated with the sigmoid sinus and exact entrance into the groove of the sigmoid sinus. The diameters and relative locations of the MF in the skull were measured and recorded. Finally, the skulls were drilled to investigate the course of the MEV. Additionally, ten latex-injected sides from human cadavers were also dissected to follow the MEV, especially in cases with more than one vein. We found that type I MFs (single foramen) were the most prevalent (50%). These MFs were mainly located on the occipitomastoid suture; only one case on the right side was adjacent to the parietomastoid suture. Type II (paired foramina) was the second most prevalent (22.73%), followed by type III (13.64%), type 0 (9.09%), and type IV (4.55%). The diameter of the external opening in a connecting MF (2.43 ± 0.79) was twice that of a non-connecting MF (1.14 ± 0.56). Interestingly, on one side, two MFs on the external surface shared a single internal opening; the MEV bifurcated. MFs followed three different courses: ascending, almost horizontal, and descending. Regardless of how many external openings there were for the MF, these all ended at a single opening in the groove for the sigmoid sinus. For cadaveric specimens with multiple MEVs, all terminated in the sigmoid sinus as a single vein, with the more medial veins terminating more medially into the sinus. Based on our study, the MF/MEV can guide the surgeon and help localize the deeper-lying sigmoid sinus. Knowledge of this anatomical relationship could be an adjunct to neuronavigational technologies.
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