Pooling of blood is what hyphema represents! This is a man who sustained an injury of uncertain mechanism to his left eye. The injury to the anterior chamber disrupted the vasculature supporting the iris or ciliary body and resulted in an hyphema, a collection of blood inside the anterior chamber of the eye (the space between the cornea and the iris). The blood tends to layer with time, and if left undisturbed, gravity will form a visible meniscus. Eventually, it may cover most or all of the iris and the pupil, blocking vision partially or completely. It is painful in many cases, and if left untreated can cause permanent vision problems. Main cause, you guessed it, trauma to the eye (mainly sports or intraocular surgeries). It is accompanied by by an increase in intraocular pressure, which usually drops after 6 days. Most uncomplicated hyphemas resolve spontaneously within days.