SIGNS AND SYMPTOMS
Patients may present with blurred vision, pain, photophobia and tearing following blunt, concussive injury to the eye or orbit. Hyphemas (blood in the anterior chamber) are described by the amount of anterior chamber (AC) they occupy:
Grade 1 = less than one-quarter of the visible volume of the AC
Grade 2 = one-quarter to one-half of the visible volume of the AC
Grade 3 = one-half to three-quarters of the visible volume of the AC
Grade 4 = complete filling of the visible AC
The term "eight-ball hemorrhage" is reserved for completely filled anterior chambers with black-colored clots.
There are two suggested mechanisms of hyphema formation. Either direct, contusive forces cause mechanical tearing of the fragile blood vasculature of the iris and/or angle, or concussive trauma creates rapidly rising intravascular pressure within these vessels, resulting in rupture.
Blood in the AC is not by itself necessarily harmful. However if quantities are sufficient it may obstruct the outflow of aqueous humor, resulting in glaucoma. Hemolytic glaucoma results from direct obstruction of the trabecular meshwork by fresh blood. Hemosiderosic glaucoma results from trabecular meshwork obstruction from degrading hemoglobin. Ghost cell glaucoma results from trabecular meshwork obstruction by the skeletons of the disintegrating red blood cells. Finally, any external force strong enough to produce internal bleeding is also sufficiently strong to produce direct damage to the adjacent trabecular meshwork, resulting in sluggish aqueous drainage (late glaucoma).
A thorough history is critical. Circumstances surrounding the event, current medicines and previous ocular history are important pieces of data. Bleeding in the eye warrants questioning concerning systemic blood disorders such as sickle cell anemia, hemophilia and Von Willebrand's disease (vascular hemophilia). If the patient is a poor historian or questions arise regarding systemic health, order systemic tests for sickle cell anemia (sickle prep or sickle dex) and bleeding disorders (PT and PTT).
Ocular examination should include an evaluation of the adnexa (X-ray, CT scan to rule out fracture or entrapment) cornea (to rule out perforation), sclera (to rule out ruptured globe), anterior chamber, lens, vitreous and retina. If a clear view of the fundus is obstructed by the hyphema or vitreous hemorrhage, perform or refer for a B-scan ultrasound of the globe.
Whether these individuals should be hospitalized is controversial. Most practitioners manage uncomplicated hyphemas (grade 1) without hospital admission. Cycloplege the patient with atropine 1% BID/QID and prescribe a steroid such as Pred Forte or Vexol Q2H/QID. If intraocular pressure is above 27mm Hg, it should be controlled using topical beta-blockers BID. When IOP requires acute attention (i.e., over 35mm Hg) prescribe acetazolamide 500mg PO BID, barring systemic contraindications, until the pressure is adequately controlled. If there are corneal epithelial defects, Rx a topical antibiotic prophylactically. Instruct the patient to limit activity to the bathroom and bed rest, laying with the head elevated at an angle of 30 degrees. Provide an eye shield for additional protection.
To prevent re-bleeding, use only acetaminophen to manage pain; avoid aspirin and ibuprofen. Referral for surgical evaluation is indicated if there is corneal blood staining, if IOP is greater than 60mm Hg, if there is an eight-ball hemorrhage or if the IOP remains above 35 for seven days. Follow up with VA, slit lamp, IOP and dilated fundus exam for four consecutive days, then as necessary.
Gonioscopy is contraindicated because it increases the risk of re-bleeding. However, up to 50 percent of patients with hyphema possess angle recession and the possibility of developing a secondary traumatic late glaucoma. Monitor the IOP of these patients regularly. The onset of secondary glaucoma is between 12 months and 50 years. Perform gonioscopy after the event has resolved and the risk of re-bleeding has passed.
Aminocaproic acid (Amicar 50mg/kg), an antifibrinolytic, has been advocated by some to reduce the risk of re-bleeding. One of its potential side effects is severe nausea and vomiting, a contraindication in patients with hyphema. The medicine seems to function best in children but is not universally accepted and remains controversial.