Painless flat bright-red blood under conjunctiva — self-limited; investigate trauma, anticoagulation, or recurrence.
Also known as: subconjunctival hemorrhage, subconjunctival hematoma, SCH
Overview
Extravasation of blood from small conjunctival or episcleral vessels into the potential space between the conjunctiva and the underlying sclera. Appears as a flat, sharply demarcated, bright-red patch with normal vision and no pain. The condition is benign and resolves spontaneously over 1-2 weeks.
Epidemiology
Very common in all age groups. Two peaks: young adults (trauma, contact lens use) and older adults (hypertension, anticoagulants, fragile vessels). Slight female predominance.
Try two board-style Subconjunctival Hemorrhage questions
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Question 1EENTEasy
A 62-year-old man on warfarin notices a bright-red patch on the white of his right eye after a bout of forceful coughing this morning. He has no eye pain, no discharge, and no change in vision, and he does not wear contact lenses. On exam there is a flat, sharply demarcated, confluent area of red discoloration over the sclera; the cornea is clear, the pupil reacts normally, and visual acuity is unchanged. Which of the following is the most likely diagnosis?
ASimple sectoral episcleritis
BSubconjunctival hemorrhage
CAnterior chamber hemorrhage
DInflamed nasal pinguecula
EAcute hemorrhagic conjunctivitis
Reveal answer & full explanation
Correct answer: B — Subconjunctival hemorrhage
ASimple sectoral episcleritis
BSubconjunctival hemorrhage✓
CAnterior chamber hemorrhage
DInflamed nasal pinguecula
EAcute hemorrhagic conjunctivitis
Why Subconjunctival hemorrhage is correct
A subconjunctival hemorrhage is blood from a ruptured small conjunctival vessel pooling beneath the conjunctiva, producing a flat, sharply demarcated bright-red patch with a completely white surrounding sclera.
It is painless, does not affect vision, produces no discharge, and is provoked by Valsalva (coughing, straining), trauma, hypertension, or anticoagulation — all fitting this warfarin user after coughing.
It is self-limited and resolves over 1-2 weeks.
Why the others are wrong
Anterior chamber hemorrhage — this is a hyphema: blood in the anterior chamber, seen through the cornea layering over the inferior iris rather than as a patch on the white of the eye; it usually follows blunt trauma and typically causes pain, photophobia, and blurred vision.
Simple sectoral episcleritis — a localized wedge of redness from dilated, radially oriented episcleral vessels that blanch with topical phenylephrine, often with mild tenderness; individual vessels are visible rather than a flat, confluent pool of blood, and it is not triggered by coughing.
Inflamed nasal pinguecula — this is pingueculitis: a pinguecula is a raised yellowish-white nodule at the nasal or temporal limbus, and when inflamed it causes surrounding injection and foreign-body irritation rather than a flat, painless red patch.
Acute hemorrhagic conjunctivitis — the name fits a bright-red eye, and this usually enteroviral infection does produce subconjunctival hemorrhages, but it is an acute, highly contagious conjunctivitis with watery discharge, foreign-body sensation or pain, and eyelid swelling, often spreading to the other eye; a single painless, sharply demarcated patch without discharge after forceful coughing in a patient on warfarin fits a simple subconjunctival hemorrhage.
Question 2EENTMedium
A 58-year-old woman has had three separate spontaneous subconjunctival hemorrhages over the past two months. Each was painless with normal vision and resolved on its own. She takes no anticoagulants and denies trauma. Which of the following is the most appropriate next step in her evaluation?
AReassure and recheck at routine follow-up
BOrder MRI of the orbits with and without contrast
CAssess blood pressure and coagulation studies
DMeasure intraocular pressure with tonometry
ERefer for bilateral carotid duplex ultrasound
Reveal answer & full explanation
Correct answer: C — Assess blood pressure and coagulation studies
AReassure and recheck at routine follow-up
BOrder MRI of the orbits with and without contrast
CAssess blood pressure and coagulation studies✓
DMeasure intraocular pressure with tonometry
ERefer for bilateral carotid duplex ultrasound
Why Assess blood pressure and coagulation studies is correct
A single subconjunctival hemorrhage is benign and needs only reassurance.
RECURRENT spontaneous hemorrhages, however, warrant a search for an underlying cause: uncontrolled hypertension and a bleeding diathesis (including occult anticoagulant use, thrombocytopenia, or a coagulopathy) are the principal culprits, so checking blood pressure and coagulation studies (with a platelet count) is the appropriate next step.
Why the others are wrong
Reassure and recheck at routine follow-up — is appropriate for an isolated single episode but inadequate once episodes recur without an obvious cause; deferring testing can miss uncontrolled hypertension or a bleeding disorder.
Order MRI of the orbits with and without contrast — orbital imaging is reserved for proptosis, an orbital mass, restricted eye movement, or significant orbital trauma; it cannot detect the hypertension or bleeding diathesis behind recurrent subconjunctival hemorrhages.
Refer for bilateral carotid duplex ultrasound — evaluates extracranial carotid stenosis after a transient ischemic attack, amaurosis fugax, or stroke; carotid atherosclerosis does not cause subconjunctival hemorrhage.
Measure intraocular pressure with tonometry — an eye-focused measurement can seem a logical response to a recurrent eye finding, and the word pressure invites confusion with the blood pressure that matters here, but a subconjunctival hemorrhage is a bleed on the ocular surface, not a sign of glaucoma or raised intraocular pressure, and tonometry cannot detect the uncontrolled hypertension or bleeding diathesis that underlies recurrent spontaneous episodes.
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Acute hemorrhagic conjunctivitis (enterovirus 70 — bilateral hemorrhages with conjunctivitis)
Recent eye or eyelid surgery
Pathophysiology
Rupture of small conjunctival or episcleral capillaries deposits blood into the subconjunctival potential space. Because conjunctiva is loosely attached and translucent, blood becomes immediately visible as a discrete bright-red patch. Resorption proceeds through the standard hemoglobin breakdown, with the patch fading through red → orange → yellow → resolution.
Clinical presentation
Symptoms
Bright red patch noticed by patient or pointed out by family — often on awakening
PAINLESS — mild scratchy or pressure sensation at most
Normal vision
No discharge
May report preceding cough, sneeze, vomiting, lifting, straining, or trauma; sometimes no inciting event
Signs / physical exam
Sharply demarcated, FLAT, bright red patch of blood under conjunctiva
Sclera underneath is opaque (blood is in conjunctival/subconjunctival plane, not intraocular)
Pupil round and reactive; visual acuity normal; cornea clear
No injection of remainder of conjunctiva
Check blood pressure; check anticoagulation status
If trauma: examine for hyphema, ruptured globe, orbital injury, foreign body — do NOT rely on subconjunctival blood to obscure these
Classic findings
Painless, flat, well-demarcated bright-red patch under the conjunctiva with normal vision and pupil.
Differential diagnosis
Hyphema — Blood in anterior chamber (between cornea and iris), often after blunt trauma; vision affected; sickle screening; bed rest with head elevation; consider IOP control
Conjunctivitis (viral, bacterial, allergic) — Diffuse injection rather than well-demarcated red patch; discharge, itching, or follicles
Acute hemorrhagic conjunctivitis (enterovirus 70) — Bilateral subconjunctival hemorrhages plus follicular conjunctivitis in outbreak; supportive care
Kaposi sarcoma of conjunctiva — Reddish-purple plaque or nodule that persists; HIV; biopsy
If recurrent or atypical: CBC, PT/INR, PTT, platelets, liver function; consider von Willebrand workup if suggestive bleeding history
Blood pressure measurement is essential
Imaging
No imaging required for typical isolated SCH
If trauma — examine for hyphema, ruptured globe; CT orbits if orbital fracture or intraocular foreign body suspected
Diagnostic algorithm
Feature
Subconjunctival Hemorrhage
Hyphema
Conjunctivitis
Location of blood/red
Under conjunctiva; flat patch
Anterior chamber (between cornea and iris)
Diffuse conjunctival injection
Pain
None
Often present, may be severe
Mild to moderate; itching in allergic
Vision
Normal
Often decreased
Usually preserved (unless keratitis)
Trauma history
Sometimes
Almost always
Rare
Workup
BP; consider anticoagulation review
Sickle screen, IOP, exclude ruptured globe
Clinical; based on type
Treatment
Reassurance, lubrication
Bed rest, head elevation, IOP control, ophthalmology
Per etiology (viral/bacterial/allergic)
Subconjunctival hemorrhage vs hyphema vs conjunctivitis — quick differentiator.
Treatment
First-line
Reassurance — SCH is benign and self-resolves over 1-2 weeks; color fades through red → yellow before disappearing
Artificial tears for any mild irritation
Cold compresses initially (24-48 h) followed by warm compresses can speed perceived resolution
Avoid aspirin/NSAIDs and vigorous activity if recent or extensive (clinical judgment)
Address blood pressure if elevated; review anticoagulation but generally do not interrupt unless indicated
Second-line / adjunct
Recurrent (>2-3 episodes) or bilateral: evaluate for bleeding disorder, hypertension, anticoagulation adjustment, or systemic disease
Refer to ophthalmology for: associated trauma with possible globe injury, vision change, pain, persistent (>3 weeks) or atypical lesion suspicious for malignancy, or coexisting hyphema
Manage hypertension and any underlying contributors
Complications
Cosmetic only — no visual or anatomic sequelae from isolated SCH
Recurrence flags a workup for hypertension or bleeding diathesis
If associated with trauma — risk lies with concomitant injuries (hyphema, globe rupture, orbital fracture) that must not be missed
PANCE pearls
Painless, flat, bright-red patch with normal vision and pupil = subconjunctival hemorrhage, not conjunctivitis or hyphema.
Always check BP, anticoagulation, and trauma history — and examine carefully for hyphema or ruptured globe in the setting of trauma.
Reassurance is the treatment; expect resolution in 1-2 weeks with color fading through orange-yellow.
Bilateral SCH with conjunctivitis in an outbreak — think enterovirus 70 (acute hemorrhagic conjunctivitis).
Recurrent SCH should prompt workup for hypertension, bleeding disorder, or systemic anticoagulant effect; isolated, infrequent SCH does not require labs.
A persistent vascular or pigmented lesion that does not resolve is not SCH — biopsy to exclude malignancy.
References
AAO EyeWiki — American Academy of Ophthalmology. Subconjunctival Hemorrhage (EyeWiki, accessed 2026)
Mimura 2009 — Mimura T et al. Subconjunctival hemorrhage and conjunctivochalasis. Ophthalmology 2009;116(10):1880-1886
Tarlan 2013 — Tarlan B, Kiratli H. Subconjunctival hemorrhage: risk factors and potential indicators. Clin Ophthalmol 2013;7:1163-1170
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