Parietal Foramen On The Parietal Bone

Description

Parietal foramen pierces the posterior part of the parietal bone near the sagittal suture, positioned just lateral to the midline on the external surface approaching the lambdoid region. From this rear (occipital) viewpoint, the opening sits on the posteromedial parietal convexity, superior to the occipital squama and posterior to the parietal eminence. Surrounding bony landmarks include the adjacent parasagittal contour of the parietal bone and the midline suture line that separates right and left parietals, making the foramen’s medial proximity easy to judge in a single frame. Clinically, the parietal foramen transmits the parietal emissary vein (and sometimes a small branch of the occipital artery), providing a potential extracranial to intracranial venous connection with the superior sagittal sinus. Infection can track along this pathway. Its size and presence vary, and an enlarged parietal foramen can be mistaken for a lytic lesion or a post-traumatic defect on skull assessment if the expected location near the posterior sagittal suture is not appreciated. The fixed posterior perspective highlights the relationship to the midline and posterior cranial vault, which is where surface landmarking and operative planning often begin when orienting a calvarial specimen or correlating with a posterior skull radiograph or CT bone window. Use this illustration for neuroanatomy and osteology teaching in head and neck courses, or as a labeled figure in atlases, exam-prep resources, and radiology learning modules addressing normal foramina versus calvarial pathology. It also fits operative anatomy references discussing parasagittal approaches and the venous implications of emissary channels near the superior sagittal sinus. Anatomical accuracy verified by SciePro's Medical Advisory Board.