Asterion (anatomy)

Asterion (Anatomy)

The asterion is a prominent anatomical landmark located on the posterior aspect of the human skull. It is formed by the junction of three cranial bones: the temporal, parietal, and occipital bones. The term "asterion" is derived from the Greek word "asteri," meaning star, due to its star-like appearance when viewed from certain angles.

Anatomy

The asterion is situated at the intersection of the lambdoid suture, which separates the occipital bone from the parietal bones, and the parietomastoid suture, which separates the parietal bone from the temporal bone. It is typically found approximately 4 centimeters above the external auditory meatus, which is the opening of the ear canal.

The asterion is easily identifiable due to its unique anatomical features. It appears as a small depression or notch on the skull surface, forming a triangular shape. The posterior branch of the middle meningeal artery, known as the asterion artery, often passes through this region.

Clinical Significance

The asterion is of clinical importance in various medical fields, including neurosurgery, radiology, and anatomy. It serves as a crucial landmark for surgical procedures involving the posterior cranial fossa, such as the placement of suboccipital craniotomy or retrosigmoid approaches.

In radiology, the asterion is used as a reference point for identifying specific structures on imaging studies, such as computed tomography (CT) scans or magnetic resonance imaging (MRI). It aids in localizing lesions or abnormalities in the posterior fossa, including tumors, vascular malformations, or traumatic injuries.

Additional Information

The asterion is also associated with certain anatomical variations and anomalies. In some individuals, the asterion may be absent or poorly developed, making it less distinct. This variation should be considered when interpreting radiological images or performing surgical procedures in this region.

Furthermore, the asterion is sometimes used as a reference point for craniometric studies, which involve measuring and analyzing the dimensions of the skull. These studies can provide valuable insights into human evolution, population genetics, and forensic identification.

See Also

• Skull
• Cranial Bones
• Posterior Cranial Fossa
• Middle Meningeal Artery
• Computed Tomography (CT)
• Magnetic Resonance Imaging (MRI)
• Craniometry