A bump appearing on the surface of the eye can be a surprising finding, but these visible abnormalities frequently relate to the conjunctiva. The conjunctiva is the thin, clear membrane that covers the white part of the eye (sclera) and lines the inner surface of the eyelids. Most growths originating from this layer are benign and common. These lesions often develop slowly in response to environmental factors like sun exposure or chronic irritation. Identifying the specific characteristics of the bump is necessary because while many are harmless, some can progress to affect vision or signal a different underlying issue.
Pingueculae: The Common Yellow Bump
The most frequently encountered type of bump on the white of the eye is a pinguecula, which manifests as a yellowish patch or raised deposit. This lesion forms when proteins, fats, or calcium accumulate within the conjunctival tissue. Pingueculae are most often found on the nasal side of the eye, closer to the nose, but they can appear on the temporal side.
This common growth is strongly associated with chronic exposure to ultraviolet (UV) light, wind, and dust. People who spend significant time outdoors in sunny or dry climates have a higher likelihood of developing these deposits. Although a pinguecula is often asymptomatic, it can become irritated, red, and swollen, a condition known as pingueculitis. Treatment for irritation usually involves lubricating eye drops, or sometimes anti-inflammatory drops if swelling is pronounced.
A defining characteristic of the pinguecula is that it remains confined to the conjunctiva and the white part of the eye. It does not grow onto the clear dome covering the iris and pupil (the cornea). This distinction is important because a pinguecula, even if large, will not directly impair vision by obstructing the visual axis. The bump may cause a foreign-body sensation, making it feel like something is stuck in the eye.
Pterygium: The Wing-Shaped Growth
A pterygium is a distinct type of fleshy, wedge-shaped growth that begins on the conjunctiva but then invades the cornea. It is sometimes referred to as “surfer’s eye” due to its strong link to chronic UV light exposure, similar to a pinguecula. Unlike the yellowish deposit of a pinguecula, a pterygium contains blood vessels, giving it a fleshy or pink appearance.
The invasive nature of the pterygium is the primary difference from a pinguecula, as it grows across the surface of the cornea. As the growth advances, it can create a pulling effect on the cornea, altering its curvature. This change in shape can induce astigmatism, leading to blurred or distorted vision. If the pterygium progresses far enough to cover the center of the cornea, it can physically block the light entering the eye, severely compromising sight.
Initial management for a pterygium involves the use of lubricating drops to reduce dryness and irritation. If the growth is rapidly advancing or begins to affect vision, surgical removal may be necessary. The goal of surgery is to excise the abnormal tissue and prevent its recurrence, often by grafting a small piece of healthy conjunctiva onto the area. Although the growth is benign, surgical intervention is sometimes required to preserve vision quality.
Less Common Causes of Localized Swelling
Beyond the chronic growths of pingueculae and pterygia, other conditions can result in a localized bump on the eyeball. Conjunctival cysts are one such cause, appearing as small, clear, fluid-filled sacs on the surface of the eye. These cysts can arise from blocked ducts or inflammation and may cause a mild foreign-body sensation or tearing. Many conjunctival cysts resolve on their own, but if they become large or bothersome, an eye care professional can drain or remove them.
Inflammation of the outer layers of the eye can also present as a localized bump, specifically nodular episcleritis. Episcleritis is an inflammatory condition affecting the episclera, the tissue layer between the conjunctiva and the sclera. The nodular form is characterized by a slightly raised, red bump in a specific sector of the eye, sometimes with tenderness. This condition is self-limiting and milder than scleritis, an inflammation of the deeper scleral tissue that causes intense, deep, and radiating pain.
This discussion focuses only on growths on the eyeball itself (the clear or white surface). Bumps that appear on the eyelid margin, such as styes or chalazia, originate from oil glands in the lid tissue. These common eyelid lesions are entirely separate conditions with different causes and management protocols.
When to Seek Medical Attention
While many growths on the eyeball are benign, professional diagnosis from an eye care provider is necessary to determine the exact cause and rule out more serious issues. If you notice a bump on your eye, an examination by an optometrist or ophthalmologist is the appropriate first step. Timely evaluation ensures that proper monitoring or treatment can begin quickly.
Certain symptoms signal a more urgent need for medical attention. These “red flag” signs include the sudden onset of severe or increasing pain, which may suggest a deeper inflammatory process like scleritis. Any change in vision, such as sudden blurring, double vision, or noticeable loss of sight, warrants an immediate visit to an eye specialist. Other concerning symptoms include bleeding from the bump, a rapid change in its size or color, or the feeling that a foreign object is lodged in the eye.