What is Subconjunctival Hemorrhage?
Having a red eye is a common reason people visit the emergency room or outpatient clinics. Usually, it’s due to something known as a subconjunctival hemorrhage. This is a condition where small blood vessels on the eye’s surface break and bleed. It generally doesn’t cause any pain, but it can make the white part of your eye look red.
Most of the time, subconjunctival hemorrhages are harmless and don’t indicate a big problem. But sometimes, if they keep happening or don’t go away, it might be a sign of a more serious underlying condition. Doctors, nurses, and eye specialists often see and treat this issue in their practice.
For some context, the surface of your eye and the inside of your eyelids are covered by a thin layer called the conjunctiva. This is divided into two parts: the bulbar conjunctiva, which covers the white part of your eye, and the tarsal conjunctiva, which lines the inside of your eyelids. When a subconjunctival hemorrhage happens, blood leaks under a layer called Tenon’s capsule and is most visible when it reaches the outward-facing part of the bulbar conjunctiva.
Older people, especially those with blood vessel-related conditions like high blood pressure and diabetes, are more likely to experience this. On the other hand, younger individuals usually have these bleeds because of a spontaneous break or injury. The good news is that subconjunctival hemorrhages typically don’t need special treatment and usually clear up on their own in one to two weeks.
What Causes Subconjunctival Hemorrhage?
Subconjunctival hemorrhages (SCH), which refer to bleeding beneath the clear outer layer of your eye, can happen in two broad ways: because of an injury (traumatic) or for no clear reason (spontaneous).
Injuries leading to SCH have become more common with the increasing use of contact lenses and the growing number of eye surgeries. Contact lens users are more likely to have certain eye conditions, such as conjunctival diseases, which increase inflammation through dryness and friction between the lenses and the eye itself. It could also disrupt the flow of tears. Poor quality or long-term use of contact lenses can lead to SCH.
Eye surgeries, particularly in patients on blood thinners, increase the risk for SCH. Certain surgeries such as cataract surgery, corrective eye surgery, or local anesthesia like sub-Tenon’s injections can increase the likelihood of SCH.
Simple actions like rubbing the eye or the presence of a foreign body can also cause SCH. Often, patients might not remember any such minor incidents. In severe cases, extensive trauma or injuries such as an open eye injury or diseases like orbital fractures can cause SCH. Basilar skull fractures can also be identified if there’s SCH occurrence without any eye injury.
In infants, bilateral subconjunctival hemorrhages (SCH in both eyes), particularly if associated with small red spots on the face, could be a sign of non-accidental trauma. Sometimes, conditions like traumatic asphyxia syndrome, caused by prolonged pressure on a child’s chest and upper abdomen, can cause SCH due to severe congestion in the veins. However, in newborns, SCH can be normal after a vaginal delivery, with a chance of occurrence being 1-2%.
The most common cause of spontaneous SCH is high blood pressure, although other conditions like diabetes and high blood lipid levels also increase the risk. These diseases can weaken blood vessels leading them to rupture spontaneously. High blood pressure remains a major risk factor for SCH whether or not it’s controlled by medication. Moreover, if blood pressure is high when SCH is first detected, it could indicate future high blood pressure.
People with conditions affecting the blood vessels are often on blood thinners like warfarin or heparin. Drugs such as aspirin and P2Y12 inhibitors like clopidogrel also increase the risk of SCH. This risk remains even if the blood is within the recommended range of clotting rate. Other factors that can cause spontaneous SCH include elevated venous pressure due to activities like coughing, vomiting, heavy exercise or lifting, and certain maneuvers that increase pressure in the abdomen. Conditions like acute hemorrhagic conjunctivitis, often caused by enterovirus 70, may lead to SCH although the occurrence of this disease is decreasing.
There are several other diseases that may first appear along with SCH such as Steven-Johnson syndrome, hemochromatosis, and certain skin vascular diseases. However, in nearly half of the cases, the cause of spontaneous SCH remains unknown.
Risk Factors and Frequency for Subconjunctival Hemorrhage
Subconjunctival hemorrhages, which are bleeds in the eye, are evenly common in all genders. However, young males typically experience more of these eye bleeds due to heavy work and engaging in aggressive activities. Whether these eye bleeds are spontaneous or due to trauma often depends on the person’s characteristics. According to a study, women have a slightly higher rate of spontaneous eye bleeds than men. As people age, especially after 50, the risk of spontaneous eye bleeds increases. This risk is higher in people who have illnesses like high blood pressure, high cholesterol, and diabetes. Interestingly, one study found that eye bleeds are more common in the summer, but this could be because children are seen by doctors more often during the summer vacation.
Signs and Symptoms of Subconjunctival Hemorrhage
A thorough medical background check and physical examination can help determine if a subconjunctival hemorrhage (SCH), or bleeding beneath the eye surface, is harmless or indicative of a more serious condition. Some people might not even be aware of the issue until they see themselves in a mirror or are informed by someone else. Doctors need to understand if there has been any eye trauma. SCH, which occurs due to blunt trauma, could hint towards a major problem like a ruptured globe or retrobulbar hematoma (bleeding behind the eyeball), and therefore needs further examination.
It’s also crucial to know about other health issues, particularly vascular disorder such as high blood pressure, cholesterol, diabetes, or medication history involving blood thinners. Other factors that could affect the eye health includes lack of medication compliance, use of contact lenses, past eye surgeries, any recent virus-like illnesses and occurrences like coughing, vomiting or constipation. If the patient reports visual loss, discharge, sensitivity to light, a sensation of a foreign body in the eye or headache, other causes need to be considered as well.
On physical examination, SCH appears as a sudden, distinct area of blood leakage just below the eye’s surface, usually on one side. It doesn’t affect the person’s eyesight ability. While a traumatic SCH is more localized, in elderly individuals, it may be more spread out. The most common SCH site is the lower outer part of the eye’s covering. Common signs like swollen eyes, protruding eyes, pus discharge, paralysis of eye muscles are not associated with a simple SCH. In cases of a ruptured sclera or the white part of the eye, blood can flow through the defect and accumulate in the subconjunctival space, leading to a raised, bubble-like looking hemorrhage.
During the physical examination, it’s essential to differentiate between redness in the conjunctiva (the transparent tissue covering the front of the eye) and ciliary (eye muscles) vessel dilations. The former is a result of the dilation of the more superficial conjunctival vessels, making the eye look unusually red over the white area. On the other hand, the dilation of the ciliary blood vessels implies inflammation inside the eye at the iris, cornea, or ciliary body. This produces a round disc of redness around the cornea and is associated with conditions such as iritis, acute glaucoma, episcleritis, and scleritis that are potentially more serious.
SCH can be mistaken with viral or bacterial conjunctivitis. However, these conditions are usually accompanied by some level of pain. Besides, the redness in these conditions is more widespread and not a precise, combined area of blood change as seen in SCH. Viral conjunctivitis impacts both the eyes, whereas SCH typically occurs in one eye.
Testing for Subconjunctival Hemorrhage
If your eye doctor suspects that you may have subconjunctival hemorrhage (SCH), a condition where the tiny blood vessels in the eye break open and cause bleeding just underneath the surface of the eye, they will use a special device called a slit lamp. The lamp shines a thin sheet of light into your eye, while your doctor looks through the lamp’s microscope. This allows them to examine the structures at the front of your eye. For this examination, they may use fluorescein, a yellow dye that makes different parts of your eye easier to see. This helps determine if there’s any damage to your eye, or if any specific eye condition caused the SCH.
Every patient who presents with SCH should also have their blood pressure checked, because high blood pressure can increase the risk of SCH. If you are taking the medication warfarin, which slows down your body’s process of blood clot formation, an International Normalized Ratio (INR) test is recommended to measure how long it takes for your blood to clot. This can help determine if your medication is contributing to your SCH.
If your SCH does not heal or keeps returning, more investigations should be done to figure out if there are any underlying issues, like conditions that affect how your blood clots. However, if you only have SCH symptoms and no other symptoms related to abnormal bleeding, more extensive blood clotting tests aren’t usually needed.
Even though a fundoscopy, a test that allows your doctor to look at the back of your eye, can provide more information about the overall health of your eyes, it typically isn’t needed if you have SCH.
Treatment Options for Subconjunctival Hemorrhage
In most cases, subconjunctival hemorrhage (SCH), which is the bursting of tiny blood vessels just beneath the clear surface of your eye, doesn’t require any treatment. The body typically absorbs the leaked blood in about 1 to 2 weeks, depending on how much blood has leaked out. If you’re taking blood-thinners, recovery might take up to 3 weeks.
To soothe any irritation, you can apply cold compresses or ice packs to help minimize swelling, and use artificial tears or over-the-counter lubricant eye drops to provide some relief from discomfort.
If you experienced eye trauma that resulted in a SCH, it’s important to see an eye specialist promptly. This is to rule out other potential injuries to the inside of the eye or retina, which is the light-sensitive tissue at the back of the eye.
Additionally, diluted eye drops containing medications such as brimonidine or oxymetazoline might be recommended to help improve comfort and lessen the likelihood of SCH occurring after injections into the eye.
What else can Subconjunctival Hemorrhage be?
If a person has had an injury to their eye, doctors need to check for certain serious conditions that could threaten the person’s sight. These include a rupture of the eyeball or a blood clot behind the eye, both of which need urgent attention from an eye specialist.
After an injury, healthcare professionals also look out for less critical but still important conditions like scratches on the eye surface, cuts to the thin layer that covers the front of the eye, foreign objects in the eye, and inflammation inside the eye.
But even if there hasn’t been an injury, other conditions can still affect the eye. Doctors check for eye inflammation, swelling, cornea damage, and inflammation inside the front part of the eye. More serious conditions that need immediate attention, like a type of emergency glaucoma, eye ulcers, internal eye inflammation and extreme inflammation of the white part of the eye also need to be ruled out.
Often, dangerous conditions can be identified just by looking at the patient. For example, if the eye is bulging, swollen, there is reduced vision, or the pupil is shaped like a teardrop, it can indicate a serious condition like a rupture or blood clot in the eye. Physical exams can also help identify other eye disorders. For instance, an abnormal pupil response to light may point to optic nerve damage, while heightened light sensitivity may signal inflammation inside the eye. Using a special device to examine the eye in combination with a dye test can provide more information about possible damage and discomfort in the eye. All these symptoms would be unexpected in simple cases of blood accumulation in the eye.
What to expect with Subconjunctival Hemorrhage
Subconjunctival hemorrhage (SCH), a condition where a tiny blood vessel breaks underneath the clear surface of the eye, generally has a good outcome after it heals. This means that your sight is usually not affected. However, there’s about a 10% chance of SCH happening again without any known risk factors. This chance may increase if you’re taking medicines that prevent blood clots, such as anticoagulants or antiplatelet therapy.
Possible Complications When Diagnosed with Subconjunctival Hemorrhage
Subconjunctival hemorrhage, or bleeding underneath the clear surface of your eye, usually resolves itself within around two weeks and doesn’t typically cause any complications. However, it’s important to note that this condition can sometimes indicate the presence of a more serious underlying health issue. These could include problems with blood clotting (coagulopathy), a serious flare-up of asthma, non-accidental injury, or significant injury to the orbit, the bony structure surrounding the eye.
Potential underlying conditions include:
- Coagulopathy (problems with blood clotting)
- Severe asthma exacerbation
- Non-accidental trauma
- Severe injury to the orbit (eye socket)
Preventing Subconjunctival Hemorrhage
If a person has a subconjunctival hemorrhage, which is bleeding just below the surface of the eye, it typically improves within two weeks. If a person notices that this condition is repeating itself or not going away, or if they find bruises on other parts of their body, they should contact their doctor. This is especially important if they are taking medication to thin their blood or prevent blood clots.
Their doctor might arrange for more tests to check on their condition. If the eye feels rough or too full, over-the-counter eye drops could be helpful.
If a person experiences loss of vision, inability to move the eye, or increasing pain and swelling, they should get in touch with their regular doctor immediately or see a specialist. These symptoms could indicate a more serious problem that needs immediate attention.