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Updated: Aug 15, 2026

2D and 3D Echocardiography in the Axolotl (Ambystoma Mexicanum)
Published on: November 29, 2018
[Topographic anatomy of the asterion]
F Martinez1, A Laxague, L Vida
1Facultad de Medicina y Hospital de Clínicas Dr. Manuel Quintela. Montevideo. Uruguay.
Background:
In the surgical approaches to the posterior fossa, the accurate location of the transverse-sigmoid sinus (TS-SS) complex is of great importance. The asterion is a referral landmark to the transverse sinus location.
Method:
Twenty-five skulls of adult cadavers were studied. We seek for the relationships of the asterion with: TS location, mastoid emissary vein, suprametal crest and inion.
Results:
The asterion was found in 49 cases. In the great majority of cases (87.8%) the asterion was over the TS (72.2% over the sinus proper, 27.8% over the TS-SS transition). The mastoid emissary vein was present in 46 cases, and in 36% we found two veins.
Discussion And Conclusions:
The burr hole for posterolateral approaches to the posterior fossa must be located below and behind the asterion.
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