The conjunctiva is a thin, transparent membrane covering the white part of the eye (sclera) and the inner surface of the eyelids. This delicate tissue is often exposed to the environment, making it a common site for abnormal growths or discolorations. A conjunctival lesion is any bump, spot, or mass on this membrane, ranging from harmless pigmentations to rare, potentially serious growths. Understanding these lesions is the first step in knowing when to seek professional medical attention.
Identifying the Most Common Benign Growths
The vast majority of growths on the conjunctiva are benign, developing slowly due to environmental factors. Two frequent benign growths are the pinguecula and the pterygium, both strongly linked to chronic ultraviolet (UV) light exposure.
A pinguecula is a yellowish, slightly raised patch, typically located near the nasal side of the cornea. This lesion is an accumulation of protein, fat, and calcium deposits and does not extend onto the clear corneal surface.
A pterygium, often called “surfer’s eye,” is a fleshy, triangular growth that actively invades and grows onto the cornea. It is vascularized, containing visible blood vessels. Its extension across the eye’s surface is the main concern for potential vision interference. Both are degenerative changes caused by chronic irritation from sun, wind, and dust exposure.
Another common benign finding is the conjunctival nevus, essentially a freckle or mole on the eye’s surface. These lesions arise from melanocytes, the pigment-producing cells, and vary widely in color from dark brown to yellow or non-pigmented. A key characteristic distinguishing a benign nevus is the frequent presence of tiny, clear fluid-filled cysts within the growth. Nevi are typically present from childhood or develop early in life, and their size and color usually remain stable. While nevi may darken or lighten due to hormonal changes, they generally do not pose a threat.
Associated Symptoms and Signs of Progression
Benign conjunctival lesions frequently cause noticeable, though typically mild, symptoms due to their physical presence. Patients often report a foreign body sensation, irritation, or grittiness. The lesion can also interfere with the tear film, leading to localized redness, dryness, or occasional inflammation (pingueculitis, if affecting a pinguecula).
Certain changes in any conjunctival lesion, even a previously stable one, should prompt an urgent evaluation. Signs of concern include a rapid increase in the size or thickness of the growth, suggesting an aggressive change. New or sudden bleeding from the lesion also warrants immediate investigation.
For a conjunctival nevus, any significant change in color or shape is a red flag, particularly if the pigmentation spreads into the surrounding tissue or becomes irregular. If a pterygium grows significantly into the central cornea and begins to impair vision or induce astigmatism, intervention is needed. The physical immobility of a growth that was previously movable over the white of the eye can also indicate a deeper, more invasive process.
Medical Evaluation and Treatment Options
Evaluation begins with a detailed examination using a slit lamp, a specialized microscope that allows the ophthalmologist to view the eye’s surface in high magnification. The doctor assesses the lesion’s location, color uniformity, presence of internal cysts, and blood vessel pattern. Photographs and precise measurements establish a baseline for monitoring future changes.
For small, stable, and clearly benign lesions, the management strategy is simple observation with regular follow-up. If the lesion causes irritation, medical management uses artificial tears for lubrication and sometimes short courses of anti-inflammatory or steroid eye drops to reduce swelling and redness. This conservative approach is effective for most non-progressing pinguecula and pterygium cases.
Surgical removal (excision) is reserved for specific situations, such as when a pterygium threatens to block the visual axis or when the lesion causes severe discomfort unresponsive to medical treatment. Excision is mandatory when there is clinical suspicion of malignancy, confirmed through a biopsy and analysis. For suspected malignant lesions, surgery involves excising the growth with a margin of healthy tissue, followed by cryotherapy (freezing) applied to the edges to destroy any remaining abnormal cells.
Recognizing High-Risk and Malignant Lesions
While rare, a small number of conjunctival lesions represent a serious health concern, primarily malignant melanoma and squamous cell carcinoma (SCC). Conjunctival melanoma is an aggressive cancer arising from melanocytes, or it can develop from primary acquired melanosis (PAM), a flat, patchy pigmentation. The presence of PAM, especially in fair-skinned adults, is a significant risk factor for progression to melanoma.
A malignant melanoma often presents as a new or changing pigmented or non-pigmented nodule, typically near the limbus (the border between the cornea and the sclera). SCC is usually a reddish or whitish, slightly gelatinous mass that may show prominent, abnormal feeder vessels.
The primary risk factor for both melanoma and SCC is excessive, chronic UV radiation exposure. Other risk factors include having light-colored eyes and fair skin, consistent with higher sun sensitivity. Unlike benign growths, any lesion displaying rapid growth, nodularity, or a change in its boundaries requires immediate, aggressive evaluation. Recognizing these specific features is paramount for early diagnosis and treatment, which significantly improves the prognosis.