Parietal foramina

The parietal foramen is an opening for the parietal emissary vein, which drains into the superior sagittal sinus. Occasionally, a small branch of the occipital artery can also pass through it. [Source: Wikipedia ]

Parietal foramina isolated
OrphaNet reference
Parietal foramina 
May Cause
Congenital skull defect
Defective cranial ossification
Radiolucent skull lesion
May Be Caused by
CDAGS syndrome