Hyphaema is the term used for blood in the anterior chamber. The main causes are trauma, post-surgery eg trabeculectomy and spontaneous. Traumatic hyphaema often results from blunt injury with rupture of the peripheral iris blood vessels. The blood tends to gravitate inferiorly and can usually be detected as a fluid level using a pen torch light. Other times the bleeding may be more subtle and only seen on slit-lamp examination (microscopic hyphaema). Specialist assessment is required as traumatic hyphaema is frequently associated with corneal abrasion, iritis, damaged pupil (sphincter rupture or mydriasis), as well as other damage to the angle, lens or posterior segment.