The interventricular foramina are the paired openings through which the lateral ventricles communicate with the third ventricle. Each opening connects its own side's lateral ventricle to the shared midline cavity. This arrangement provides a route for cerebrospinal fluid to reach the rest of the ventricular system.[ref]
Both sides reach the shared third ventricle, which joins the fourth ventricle through the cerebral aqueduct.
Measurements add a temporal picture to this connection map. In a 1991 study, phase-contrast magnetic resonance imaging encoded the direction of cerebrospinal fluid movement across the cardiac cycle. The ventricular measurements contained systolic and diastolic flow components, with essentially simultaneous timing at the interventricular opening and cerebral aqueduct. Anatomical continuity and measured pulsatile transport describe complementary features of the same pathway.[ref]
Lateral ventricle 2026-11-05
A lateral ventricle is one of the two large cerebrospinal fluid-filled cavities within the cerebral hemispheres. Each connects with the third ventricle through an interventricular foramen. Its location inside a hemisphere makes it a useful landmark when interpreting sections or images of the brain.[ref]
The choroid plexus projects into ventricular cavities and contributes to cerebrospinal fluid production; the ependyma lines the ventricular wall. The resulting environment joins a secretory interface, a fluid compartment and neighbouring neural tissue. These components have different roles even though they appear close together in an anatomical section.[ref]
The connections below provide a simplified route through the ventricular system. Actual transport also has a time dependence: phase-contrast magnetic resonance imaging has resolved cerebrospinal fluid movement over the cardiac cycle, while work on the third ventricle has revealed structured local flows driven by motile cilia.[ref][ref]
Figure 1.
Anatomical connections of the ventricular system
. Original schematic showing paired lateral ventricles, the interventricular foramina, third ventricle, cerebral aqueduct, fourth ventricle and subarachnoid spaces. Arrows follow the conventional passage sequence; cerebrospinal fluid also undergoes pulsatile movement and local recirculation.[ref] Details.