Vitreous hemorrhage from a persistent hyaloid artery.

A 14-year-old girl developed spontaneous vitreous hemorrhage from the free end of a partially regressed hyaloid artery. Fluorescein angiography confirmed the hemorrhage was from the retinal arterial rather than venous circulation. The vessel became a fibrosed, occluded, and semitransparent thread after 20 months of follow-up evaluation. It was postulated that the rapid eye movement (REM) phase during sleep may create a tractional force and leads to rupture of the freely floating hyaloid artery. A patent persistent hyaloid artery should be included in the list of the causes of vitreous hemorrhage, especially in healthy young people.