Normal craniovascular variation in two modern European adult populations

Abstract

The vascular networks running into the meningeal layers, between the brain and braincase, leave imprints on the endocranial surface. These traces are visible in osteological specimens and skeletal collections, providing indirect evidence of vascular patterns in those cases in which bone remains are the only source of anatomical information, such as in forensic science, bioarchaeology and paleontology. The main vascular elements are associated with the middle meningeal artery, the venous sinuses of the dura mater, and the emissary veins. Most of these vascular systems have been hypothesized to be involved in endocranial thermal regulation. Although these traits deal with macroanatomical features, much information on their variation is still lacking.In this survey, we analyze a set of craniovascular imprints in two European dry skull samples with different neurocranial proportions: a brachycephalic Czech sample (n = 103) and a mesocephalic Italian sample (n = 152). We analyzed variation and distribution, correlation with cranial metrics, and sex differences in the dominance of the branches of the middle meningeal artery, the patterns of confluence of the sinuses, and the size of the emissary foramina. The descriptive statistics provide a reference to compare specimens and samples from different case studies. When compared with the Italian skulls, the Czech skulls display a greater dominance of the anterior branch of the middle meningeal artery and more asymmetric right-dominance of the confluence of the venous sinuses. There is no sex difference in the middle meningeal vessels, but males show a greater prevalence of the occipito-marginal draining system. Differences in the middle meningeal vessels or venous sinuses are apparently not influenced by cranial dimensions or proportions. The mastoid foramina are larger in larger and more brachycephalic skulls, which increases the emissary potential flow in the Czech sample and males, when compared with the Italian samples and females, respectively. The number of mastoid foramina increases in wider skulls. This anatomic information is necessary to develop further morphological and functional inferences on the relationships between neurocranial bones and vessels at the genetic, ontogenetic, and phylogenetic levels.

Tracing craniovascular traits in artificially modified pre‐Columbian crania from Cuba, the largest Caribbean archipelago

“…When considering emissary foramen size, the results suggest that the CC and MEF, followed by PEF, played an important role in endocranial blood drainage related to the emissary vein. This is consistent with previous studies on modified (Ossenberg, 1970) and unmodified crania (Eisová et al, 2019). However, the small‐sized OEF found in this study suggests that the pressure exerted by fronto‐occipital modification could decrease vascular drainage in this area, whereas in the unaffected regions, there was compensatory supply.…”

“…The position, patterns, and population differences of CVT have been studied in numerous modern human samples (Bruner, Averini, & Manzi, 2003; Eisová, Píšová, Velemínský, & Bruner, 2019; Hauser & De Stefano, 1989), including artificially modified skulls (Dean, 1995; Grupe, 1984; O'Loughlin, 1996; Ossenberg, 1970). However, as far as is known, there are no published studies that analyze CVT in artificially modified pre‐Hispanic crania from the insular Caribbean, a region where these samples are not commonly found.…”

Craniovascular traits and braincase morphology in craniosynostotic human skulls

“…The variability of the MMA, DVS, and emissary foramina has previously been described in anatomically normal adults (Bruner et al, 2003;Eisová et al, 2019). The normal intra-population and inter-population differences of the craniovascular traits seem in general to be unrelated to cranial form (Eisová et al, 2019) and shape (Bruner et al, 2009).…”

“…The variability of the MMA, DVS, and emissary foramina has previously been described in anatomically normal adults (Bruner et al, 2003;Eisová et al, 2019). The normal intra-population and inter-population differences of the craniovascular traits seem in general to be unrelated to cranial form (Eisová et al, 2019) and shape (Bruner et al, 2009). Accordingly, in anatomically normal individuals genetic and epigenetic factors probably influence the craniovascular morphology independently from the cranial proportions (Bruner et al, 2003;Eisová et al, 2019).…”

“…Parietal, condylar, and mastoid foramina, that transmit parietal, condylar, and mastoid emissary veins respectively, are commonly observed (e.g. Boyd, 1930;Eisová et al, 2019;Hampl et al, 2018;Louis et al, 2009;Mortazavi et al, 2012;Píšová et al, 2017;Schumacher & Tubbs, 2020;Tubbs et al, 2016). Sometimes, a foramen of Vesalius is formed by the sphenoparietal emissary vein (Chaisuksunt et al, 2012;Leonel et al, 2019;Ozer & Govsa, 2014;Raval et al, 2015;Rossi et al, 2010), and occasionally an occipital foramen is created by the occipital emissary vein (Boyd, 1930;Eisová et al, 2019;Louis et al, 2009).…”