Traumatic subconjunctival hemorrhage is a condition in which a conjunctival blood vessel ruptures due to a blow or other eye trauma, and blood collects in the subconjunctival space (between the bulbar conjunctiva and Tenon’s capsule). It is said to account for 10–20% of all subconjunctival hemorrhages1).
Unlike non-traumatic subconjunctival hemorrhage (idiopathic, hypertension, anticoagulant use, Valsalva maneuvers, etc.), traumatic cases are clinically important because they can be a sign of serious injury inside the eye. Subconjunctival hemorrhage itself is benign, but when it is seen after trauma, it is necessary to systematically rule out hidden ocular injury.
Subconjunctival hemorrhage is found in about 3% of ophthalmology outpatients and reaches 10.1% in people aged 65 years or older2). In Tarlan et al.’s review, idiopathic cases accounted for 30–50% of all subconjunctival hemorrhages, hypertension for 10–30%, and trauma for 10–20%1). Detailed epidemiologic data limited to traumatic cases are scarce, but sports, work, traffic accidents, and accidents at home are the main causes of injury.
If there is no associated intraocular injury, traumatic subconjunctival hemorrhage is absorbed naturally within 1 to 4 weeks and leaves no lasting effects. During the absorption process, the blood changes from red to purple to blue-green to yellow. It does not affect vision. However, the presence or absence of an associated ocular injury determines the prognosis, so careful initial evaluation is essential.
The subconjunctival hemorrhage itself resolves naturally in 1 to 4 weeks and does not affect vision. However, subconjunctival hemorrhage after trauma can be a sign of injury inside the eye (globe rupture, conjunctival laceration, hyphema, etc.), so it is important to see an ophthalmologist even if there is no pain. In particular, 360-degree subconjunctival hemorrhage or cases with decreased vision or marked low intraocular pressure are urgent.
Features of a benign course
Localized hemorrhage: the bleeding remains limited to part of the conjunctiva.
Normal eye pressure: Eye pressure is within the normal range by palpation or non-contact tonometer.
Normal pupil: Normal light response and pupil shape.
Normal vision: Corrected vision is the same as before the injury.
Warning signs that suggest globe rupture
360-degree subconjunctival hemorrhage: Bleeding all around the eye is an important sign of a possible occult globe rupture.
Marked low eye pressure: The globe feels soft on finger palpation (if open globe injury is suspected, do not use a tonometer).
Pupil deviation, distortion, or fixation: Suggests prolapse of anterior segment tissue.
Anterior chamber hemorrhage and decreased vision: Suggests severe injury inside the eye.
360-degree subconjunctival hemorrhage may be a sign of a possible occult globe rupture. If it is accompanied by marked low eye pressure, decreased vision, or pupil distortion, the situation is urgent, and orbital CT and ocular exploration may be considered. If these findings are present, you need to see an eye specialist on the same day.
The mechanisms of injury in traumatic subconjunctival hemorrhage are varied.
The following risk factors increase the incidence of subconjunctival hemorrhage, whether traumatic or non-traumatic.
Evaluate subconjunctival hemorrhage after trauma systematically using the following steps.
Clinical diagnosis
History taking: Check the circumstances of the injury, how it happened, and any history of taking anticoagulants.
Slit-lamp microscopy: assess the extent and color of the hemorrhage, and check for conjunctival laceration and corneal damage.
Seidel test: after fluorescein staining, confirm whether there is any aqueous humor leakage from the bleeding site.
Intraocular pressure measurement: by finger palpation or non-contact method (contact tonometry is contraindicated if an open-globe injury is suspected).
Systemic and imaging tests
Blood pressure measurement: essential as screening for hypertension.
Blood tests: in patients taking anticoagulants, check INR, PT, APTT, and platelet count.
Orbital CT: in cases of 360-degree hemorrhage or low intraocular pressure, evaluate the continuity of the globe wall, intraocular foreign bodies, and the presence of fractures.
Dilated fundus examination: to rule out commotio retinae, retinal tears, and vitreous hemorrhage.
It is necessary to distinguish this from the following conditions.
| Differential diseases | Differentiating points |
|---|---|
| Idiopathic subconjunctival hemorrhage | No history of trauma, normal intraocular pressure, benign course |
| Globe rupture | 360-degree hemorrhage, low intraocular pressure, pupil deformity, hyphema |
| Conjunctival laceration | Laceration beneath the hemorrhage, Seidel test positive |
| Acute hemorrhagic conjunctivitis | Bilateral, follicular conjunctivitis, preauricular lymph node swelling, epidemic history |
| Subconjunctival Kaposi sarcoma | Dark red nodules, HIV-related, does not resolve for a long time |
The treatment of traumatic subconjunctival hemorrhage prioritizes treatment of the associated globe injury rather than the subconjunctival hemorrhage itself.
If there is no associated globe injury, let the subconjunctival hemorrhage run its natural course. It is naturally absorbed in 1 to 4 weeks. There is currently no established treatment that speeds absorption.
| Medication | Dosage | Indication |
|---|---|---|
| Artificial tears | Instill as needed | Symptomatic relief of discomfort |
| Carbazochrome sodium sulfonate (Adona®) 30 mg | Take orally 3 times a day | Capillary strengthening (if recurrent) |
For bothersome symptoms, provide supportive care with artificial tears. If dry eye is present, consider prescribing 3% diquafosol sodium eye drops, 2% rebamipide suspension eye drops, sodium hyaluronate eye drops, and similar treatments. For repeated bleeding, carbazochrome sodium sulfonate (Adona® tablets 30 mg, taken orally 3 times a day) may be used, but the level of evidence is not high.
In patients taking warfarin, confirm by blood test whether the INR is within the therapeutic range (most often 2.0–3.0). Stopping anticoagulants on your own is strictly prohibited because it carries a risk of stroke and cardiogenic embolism. Be sure to discuss the matter with the primary doctor and respond accordingly 3).
At present, there is no established treatment that promotes the absorption of subconjunctival hemorrhage. During the resorption process, it changes color from red to purple to blue-green to yellow, which is a normal course. Warm compresses are sometimes recommended empirically, but evidence is limited. If there is a concomitant eye injury (such as conjunctival laceration or hyphema), prioritize treatment of that injury.
Stopping anticoagulants on your own is strictly prohibited because it carries a risk of stroke and cardiogenic embolism. Check that the therapeutic range is maintained with tests such as INR, and respond after consulting the primary doctor. The incidence of subconjunctival hemorrhage in patients taking warfarin is 3.7% (1.7% in non-users) 3), and after trauma the bleeding tends to spread more easily, but the decision to stop the medication should be made by a specialist.
Direct blunt force causes physical injury to the conjunctival vessels, allowing blood to leak into the subconjunctival space. In older adults, the elastic tissue and connective tissue between Tenon’s capsule and the conjunctiva are more fragile, so the same force is more likely to cause bleeding that spreads widely.
In globe rupture caused by blunt trauma, a sudden rise in intraocular pressure causes a tear at the thinnest part of the eyeball wall, near the corneal limbus and rectus muscle insertions. Intraocular blood and vitreous spill into the subconjunctival space, appearing as widespread subconjunctival hemorrhage. Circumferential subconjunctival hemorrhage is a characteristic finding of this mechanism.
It has been reported that conjunctival lymphatic vessels may be involved in the absorption of subconjunctival hemorrhage. Intraoperative OCT has shown blood within lymphatic vessels with valve-like structures adjacent to the bleeding site, suggesting that lymphatic vessels help clear blood from the subconjunctival space4).
In diabetes, the conjunctival microvessels may become dilated, tortuous, and show changes in blood flow speed, increasing vessel fragility. As a result, even minor trauma can more easily cause subconjunctival hemorrhage.
The drainage mechanism of subconjunctival hemorrhage through conjunctival lymphatic vessels was demonstrated for the first time using intraoperative OCT4). In a case of SCH that occurred during cataract surgery, blood transfer into lymphatic vessels with valve-like structures was confirmed, and marked resolution of SCH within 1 to 2 days after surgery was reported. This finding may also be useful for predicting outcomes after glaucoma filtering surgery.
Standardization of an algorithm to distinguish traumatic subconjunctival hemorrhage from globe rupture is needed. There are also reports that quantitative assessment of the depth and extent of subconjunctival hemorrhage using anterior segment OCT may help improve diagnostic accuracy, but it has not yet become widely used in clinical practice.
