Which sign is associated with agenesis of the corpus callosum and describes enlargement and upward displacement of the third ventricle with outward angling of the frontal and lateral horns?

Which sign is associated with agenesis of the corpus callosum and describes enlargement and upward displacement of the third ventricle with outward angling of the frontal and lateral horns?

• A. Steer sign
• B. Trident sign
• C. Mickey sign
• D. V sign

Answer: (A)

Agenesis of the corpus callosum changes how the ventricles arrange themselves. Without the corpus callosum, the lateral ventricles expand and their frontal horns flare outward, while the third ventricle sits higher than normal. This combination creates a silhouette that resembles a steer, which is described as the Steer sign. This sign on imaging helps distinguish ACC from other ventricular configurations by highlighting the outwardly angulated frontal and lateral horns and the upward displacement of the third ventricle. Other signs describe different shapes of the ventricular system and aren’t the characteristic steer-like configuration seen with ACC, so they don’t fit the described pattern as accurately.

Agenesis of the corpus callosum changes how the ventricles arrange themselves. Without the corpus callosum, the lateral ventricles expand and their frontal horns flare outward, while the third ventricle sits higher than normal. This combination creates a silhouette that resembles a steer, which is described as the Steer sign. This sign on imaging helps distinguish ACC from other ventricular configurations by highlighting the outwardly angulated frontal and lateral horns and the upward displacement of the third ventricle.

Other signs describe different shapes of the ventricular system and aren’t the characteristic steer-like configuration seen with ACC, so they don’t fit the described pattern as accurately.