A subconjunctival hemorrhage occurs when a small blood vessel breaks underneath the conjunctiva, the clear membrane covering the white part of your eye. This leads to a bright red patch on the eye’s surface, which can appear alarming. A “bullous” subconjunctival hemorrhage represents a more pronounced form of this condition, where the bleeding is significant enough to create a raised, blister-like collection of blood. While its appearance can be startling, this type of hemorrhage is generally harmless and often resolves without intervention.
Understanding Bullous Subconjunctival Hemorrhage
A bullous subconjunctival hemorrhage is a prominent, elevated collection of blood beneath the conjunctiva. This thin, transparent membrane covering the white part of your eye and the inner surface of the eyelids. The bleeding occurs in the space between the conjunctiva and the sclera.
When tiny blood vessels within the conjunctiva rupture, blood leaks into this subconjunctival space. Because the conjunctiva cannot absorb blood quickly, the blood becomes trapped, leading to the characteristic red patch. In a bullous subconjunctival hemorrhage, the volume of trapped blood is greater, causing the conjunctiva to lift and form a noticeable blister-like bulge, distinguishing it from a typical, flatter subconjunctival hemorrhage.
Common Causes and Risk Factors
Various factors can lead to a bullous subconjunctival hemorrhage, often involving a sudden increase in pressure within the small blood vessels of the eye. Common actions that can cause this include straining during coughing, powerful sneezing, vomiting, or lifting heavy objects. Even vigorously rubbing the eye can result in minor trauma that causes capillaries to break.
Certain medical conditions and medications also increase the risk. High blood pressure is a frequent systemic risk factor, as it can make blood vessels more fragile. Diabetes and arteriosclerosis are other systemic vascular diseases that can contribute to vessel wall fragility. Additionally, blood-thinning medications can increase the likelihood and extent of bleeding.
When to Seek Medical Attention
While most bullous subconjunctival hemorrhages are benign and resolve on their own, certain symptoms warrant immediate medical evaluation. Persistent eye pain or any changes in vision, such as blurriness, double vision, or vision loss, should prompt a consultation. Discharge from the eye, along with redness or swelling around the eye, could indicate an infection.
A history of recent head or eye trauma, especially if the hemorrhage is extensive or accompanied by other signs like periorbital bruising or decreased eye movement, requires prompt assessment to rule out more serious conditions like a scleral laceration or orbital fractures. Recurrent hemorrhages, or if accompanied by systemic symptoms like severe headache, nausea, weakness, or unexplained bruising elsewhere on the body, also suggest the need for further medical investigation to identify underlying conditions such as bleeding disorders or systemic vascular issues.
Management and Recovery
Most bullous subconjunctival hemorrhages do not require specific medical treatment and resolve without intervention. The body naturally absorbs the blood over time, similar to how a bruise fades. For comfort, applying cold compresses initially can help, followed by warm compresses later. Artificial tears can be used to alleviate any mild irritation or scratchy sensation in the eye.
The resolution timeline for a subconjunctival hemorrhage ranges from one to three weeks, depending on its size. As the blood dissipates, the red patch will gradually change color, often progressing through shades of brown, purple, and yellow, mimicking the appearance of a fading bruise. Throughout this healing period, vision is unaffected, and the condition does not impair sight unless an underlying eye injury or systemic issue is present.