CSF, Ventricles & Brain Anatomy
Atrium (trigone) of the lateral ventricle
The atrium, or trigone, is the region where the body and horns of the lateral ventricle meet, containing a prominent tuft of choroid plexus.
In short: Atrium (trigone) of the lateral ventricle
- It is the junction of the body and the occipital and temporal horns.
- It contains a prominent collection of choroid plexus.
- It is a reference region on imaging.
- Its size contributes to assessing ventricular enlargement.
What it is
The atrium (also called the trigone) is the wider region of the lateral ventricle where its body meets the occipital and temporal horns. It contains a prominent tuft of choroid plexus called the glomus.
Understanding Atrium (trigone) of the lateral ventricle
Because several parts of the lateral ventricle converge here and a large amount of choroid plexus is present, the atrium is a notable landmark on imaging. Its size is part of assessing the degree of ventricular enlargement in hydrocephalus, and the choroid plexus here is a source of CSF production. Radiologists reference the atrium when characterizing the ventricular system.
Why it matters
Understanding the atrium helps families recognize a key landmark of the lateral ventricle that is referenced on imaging and contributes to assessing ventricular size.
Common questions
What is the atrium of the lateral ventricle?
The junction of the body and the occipital and temporal horns.
What does it contain?
A prominent collection of choroid plexus.
Why is it referenced?
It is a landmark used in assessing ventricle size.
Bottom line
The atrium (trigone) is the junction region of the lateral ventricle, containing prominent choroid plexus and used as an imaging landmark.
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