Brain Ventricles' Atrium Of The Lateral Ventricle, Anterior View

Description

Atrium (trigone) of the lateral ventricle occupies the posterior central ventricular cavity where the body expands and transitions into the occipital horn posteriorly and temporal horn inferolaterally, presented in a frontal orientation. Medially, the ventricular wall relates to the septum pellucidum and the body of the fornix, while superior contours approach the undersurface of the corpus callosum near the splenium. Laterally, the atrial margin is formed by callosal fibers (tapetum) and adjacent deep white matter, framing the triangular CSF space that characterizes this junction. Choroid plexus is expected along the atrial floor, near the region of the glomus. Radiologists and neurosurgeons care about the atrium because it is a common site of ventricular enlargement in obstructive or communicating hydrocephalus and a frequent location for a prominent choroid plexus glomus that can be mistaken for hemorrhage on imaging. Size matters. The fixed frontal perspective helps users correlate the atrial boundaries with axial and coronal CT or MRI anatomy when assessing intraventricular hemorrhage, ventriculitis, or asymmetric ventricular dilatation, and it supports teaching the relationship between ventricular horns and periventricular white matter tracts at the posterior cerebrum. For intraventricular neuroendoscopy planning, appreciating how the atrium sits posterior to the thalamus and medial to the deep parietal white matter reduces ambiguity when discussing trajectories and landmarks. Use this illustration in neuroanatomy and neuroradiology courses to anchor the terminology of atrium versus trigone, and in atlases or review articles addressing hydrocephalus, ventricular system anatomy, or ventricular catheter placement. It also suits patient-facing neurosurgical education materials when explaining ventricular enlargement and CSF pathways without oversimplifying the anatomy. Anatomical accuracy verified by SciePro's Medical Advisory Board.