<prompt> All are true about blackball hyphema EXCEPTAC completely filled with bright red blood is total hyphema, blackball hyphema if dark red bloodAlso called Eight ball hyphemaThe black colour is suggestive of impaired aqueous circulation and decreased oxygenBlackball hyphema causes less pupillary block and less angle closure  <response>: Post-traumatic hyphema is an ophthalmologic emergency that can result in permanent vision loss. Accumulation of blood in the anterior chamber causes trabecular meshwork obstruction, thereby elevating IOP. Hyphema with increased IOP can result in corneal blood staining, reduced corneal transparency, and vision loss. Hyphemas are graded by the percentage of the anterior chamber AC filled with blood, and range from Grade I blood occupying 13 of the AC to Grade IV blood occupying 100 of the AC, or eight-ball eye. 