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Hyphema and Microhyphema

URGENT — Trauma

Symptoms

  • Blurred vision, eye pain, photophobia, and tearing following trauma
  • History of high-velocity injury (e.g., ball, fist, airbag, BB pellet)
  • History of sickle cell disease/trait, anticoagulant use, or bleeding diathesis
  • Microhyphema: subtle drop in vision or dull ache (often an incidental finding)
  • Spontaneous hyphema: transient visual loss or presentation without a history of trauma

Clinical Findings

Hyphema Grading (Wills Eye)

  • Microhyphema: RBCs suspended in the AC; no macroscopic layering (visible via slit lamp only)
  • Grade I: Layered blood filling <1/3 of the anterior chamber volume
  • Grade II: Layered blood filling 1/3 to 1/2 of the anterior chamber volume
  • Grade III: Layered blood filling 1/2 to near-total of the anterior chamber volume
  • Grade IV (8-ball hyphema): Total dark, deoxygenated clot completely filling the anterior chamber

Associated Clinical Signs

  • Layered red blood in the AC that gravitates inferiorly with head position
  • Elevated IOP and secondary rust-colored corneal blood staining
  • Iris/angle trauma: iridodialysis, angle recession, and pupillary irregularities/sphincter tears
  • Posterior segment trauma: commotio retinae, vitreous hemorrhage, lens subluxation, or retinal dialysis

Etiology

Traumatic Causes

  • Blunt ocular trauma (most common): mechanical disruption of iris or ciliary body vasculature
  • Penetrating ocular trauma: requires immediate exclusion of an open or ruptured globe

Spontaneous & Non-Traumatic Causes

  • Post-surgical/Device-related: Uveitis-Glaucoma-Hyphema (UGH) syndrome caused by iris-IOL chafing
  • Anterior segment neovascularization: rubeosis iridis secondary to diabetic retinopathy, old CRVO, or OIS
  • Inflammatory/Uveitic: herpetic keratouveitis or Fuchs heterochromic iridocyclitis
  • Intraocular tumors: juvenile xanthogranuloma (JXG), iris melanoma, or retinoblastoma
  • Systemic & Pharmacological: systemic anticoagulants, antiplatelets, or underlying bleeding diatheses

Red Flags

  • Sickle cell trait or disease: rigid RBCs cannot clear the trabecular meshwork; an IOP ≥24 mmHg risks rapid optic nerve infarction
  • Rebleed window (days 2–5): highest risk occurs as the initial clot retracts and lyses; rebleeds are often more severe than the primary event
  • Systemic CAI contraindication: strictly avoid acetazolamide and hyperosmotics (mannitol) in sickle cell patients as it induces hypoxia/acidosis and worsens sickling
  • Early corneal blood staining: a critical red flag indicating the immediate necessity for surgical AC washout
  • Delayed presentation: must rule out an occult or posterior globe rupture hidden by periocular swelling

Investigations

Clinical Diagnostics

  • Baseline visual acuity, daily applanation IOP measurements, and detailed slit-lamp grading
  • Dilated fundus examination (avoiding scleral depression acutely) once globe integrity is fully confirmed

Laboratory & Imaging Workup

  • Sickle cell screen (Sickledex / Hb electrophoresis): mandatory for all at-risk ethnicities or patients with unknown status
  • CT scan of the orbits: indicated if orbital fractures or an intraocular foreign body (IOFB) are suspected
  • B-scan ultrasonography: indicated if a dense hyphema or vitreous hemorrhage completely obscures the posterior segment view
  • Coagulation panel (CBC, PT/INR, and PTT) for all spontaneous, non-traumatic cases
  • Delayed Gonioscopy: safely perform at 4 weeks post-injury to document the presence and extent of angle recession

Treatment

Medical Management

  • Topical prednisolone acetate 1% (ranging from QID to Q1h depending on inflammation levels)
  • Topical cycloplegia: atropine 1% drops (daily to BID) to stabilize the blood-aqueous barrier and prevent synechiae
  • IOP control (Non-Sickle): topical beta-blockers, alpha2-agonists, or topical CAIs (strictly avoid miotics like pilocarpine)
  • IOP control (Sickle Cell): treat aggressively; use topical agents and consider oral methazolamide if a systemic CAI is absolutely required

Surgical Intervention (AC Washout)

  • Indications: IOP >60 mmHg for 48 hours, IOP >50 mmHg for 5 days, or a total (8-ball) hyphema persisting >5 days with IOP ≥25 mmHg
  • Any initial manifestation of impending corneal blood staining requires immediate washout
  • Sickle cell patients carry a significantly lower threshold for surgical intervention due to low pressure tolerance

Clinical Pearl

Sickle cell + hyphema is a true ophthalmic emergency: sickled RBCs clog the trabecular meshwork and can infarct the optic nerve at IOP levels that normal eyes tolerate (~24 mmHg). Screen every at-risk patient, avoid systemic acetazolamide or hyperosmotics, and lower your threshold to wash out the AC. Rebleed risk peaks at days 2–5 as the clot naturally retracts; enforce activity restrictions and avoid all NSAIDs/aspirin.

Differential Diagnosis

  • • Neovascular hyphema (associated with rubeosis iridis and neovascular glaucoma)
  • • UGH (Uveitis-Glaucoma-Hyphema) syndrome
  • • Primary anterior uveitis with a dense fibrinous or hypopyon reaction
  • • Iris or ciliary body tumors (e.g., juvenile xanthogranuloma, iris melanoma, retinoblastoma)
  • • Systemic bleeding diathesis or over-anticoagulation
  • • Traumatic open or ruptured globe

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