A unique finding of cavum velum interpositum colloid-like cyst and literature review of a commonplace lesion in an uncommon place.

Colloid cysts typically reside within the area of the anterior third ventricle, in the proximity of the foramen of Monro. Although they are considered to commonly localize in various parts of the cerebrum, they are exceedingly rare outside the ventricular system and rarely occur within the velum interpositum. We have reported here a rare case of a velum interpositum colloid-like cyst in a 23-year-old man, who presented to our clinic with temporary binocular strabismus, which he had been experiencing for the previous year. In addition, we have briefly reviewed evidence regarding the generation, anatomy, and pathogenesis of colloid cysts, as well as the management options for such rare cases. The present report is only the third to describe a colloid-like cyst located within the velum interpositum, providing additional data that may aid in elucidating the pathogenesis of these neoplasms.