Venous Lacunae, Posterior View

Description

Posteriorly, the venous lacunae (lacunae laterales) sit as paired dural venous spaces lateral to the superior sagittal sinus as it approaches its terminal segment near the internal occipital protuberance and confluence of sinuses. The occipital pole of the cerebral hemispheres lies superior to the cerebellum, while the cerebellar hemispheres and vermis occupy the posterior cranial fossa inferiorly, separated from the occipital lobes by the tentorium cerebelli. A web of bridging veins courses from the superficial cerebral veins toward the midline, entering the superior sagittal sinus and adjacent lacunae, with the dural reflections forming a firm boundary against the calvaria. Clear midline anatomy. That relationship matters because the lacunae communicate with meningeal veins and arachnoid granulations, so their size and position influence venous outflow patterns and CSF resorption along the superior sagittal sinus. Posterior parasagittal surgery and occipital craniotomy planning often hinge on avoiding injury to bridging veins near the lacunae, a common source of troublesome venous bleeding and a contributor to postoperative venous infarction when sacrificed. Radiologists also use this anatomy to distinguish normal lacunar expansions from dural venous sinus thrombosis or flow gaps on MR venography. Use this artwork for neuroanatomy and neuroscience teaching when covering dural venous sinuses, confluence variants, and the tentorium, and for neurosurgical texts illustrating the posterior midline corridor and parasagittal venous hazards. It also fits neuroradiology chapters on venous sinus anatomy and interpretation of posterior SSS and torcular region imaging. Anatomical accuracy verified by SciePro's Medical Advisory Board.