Diagnosis & Imaging
Frontal and occipital horn ratio (FOHR)
The frontal and occipital horn ratio is a measurement of ventricle size on imaging, often used to monitor hydrocephalus in children.
In short: Frontal and occipital horn ratio (FOHR)
- It is a ratio based on the size of the frontal and occipital horns.
- It quantifies ventricular enlargement.
- It is often used to track ventricle size over time in children.
- It is interpreted alongside the clinical picture.
What it is
The frontal and occipital horn ratio (FOHR) is a measurement on brain imaging that compares the size of the frontal and occipital horns of the lateral ventricles to the skull width. It is used to quantify ventricular enlargement, particularly in children.
Understanding Frontal and occipital horn ratio (FOHR)
The FOHR incorporates measurements of both the frontal and occipital horns, providing an assessment of ventricle size that is often used to monitor hydrocephalus over time in children. By using a consistent measurement, the team can track whether the ventricles are enlarging, stable, or decreasing — for example, before and after treatment. The FOHR is one of several indices (along with the Evans index and others) used to quantify ventricle size, and it is interpreted alongside the clinical picture, since the goal is to understand the trend and the child's overall status, not a single number in isolation.
Why it matters
Understanding the FOHR helps families interpret imaging reports and see how a standardized measurement is used to track ventricle size over time in children with hydrocephalus, including after treatment.
Common questions
What is the FOHR?
A ratio based on the frontal and occipital horns and skull width.
What is it used for?
Quantifying and monitoring ventricular enlargement, especially in children.
Is a single value enough?
No — it is interpreted alongside the trend and clinical picture.
Bottom line
The frontal and occipital horn ratio is an imaging measurement used to quantify and monitor ventricle size over time, especially in children.
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