Conjunctival Nevus in a Child: Key Signs & Considerations

A conjunctival nevus is one of the most common benign eye lesions in children. While usually harmless, its appearance can cause concern for parents. Recognizing key signs and knowing when further evaluation is needed ensures proper monitoring and management. Because these growths vary in presentation, distinguishing them from other ocular conditions is essential.

Common Appearance And Characteristics

A conjunctival nevus in a child typically appears as a well-defined, slightly raised lesion on the conjunctiva, the transparent membrane covering the white part of the eye. These nevi often develop near the limbus, the border between the cornea and sclera, but can also occur elsewhere on the conjunctiva. Their coloration ranges from light brown to dark brown, though some may appear yellowish or nearly colorless. Pigmentation can change over time, sometimes darkening during puberty due to hormonal influences. Unlike malignant lesions, conjunctival nevi grow slowly and remain stable for long periods, though slight enlargement may occur as the child matures.

A distinguishing feature of these lesions is the presence of cystic spaces, appearing as translucent or fluid-filled areas visible under slit-lamp examination. These cysts are a hallmark of benign conjunctival nevi and help differentiate them from more concerning ocular growths. The surface is usually smooth, though some may have a slightly lobulated texture. In some cases, eye irritation or inflammation can make the lesion more prominent, temporarily altering its appearance. However, conjunctival nevi typically do not cause discomfort, redness, or vision changes, distinguishing them from inflammatory or infectious conditions.

Subtypes Of Conjunctival Nevus

Conjunctival nevi are classified based on pigmentation and structural characteristics. The three primary subtypes are pigmented, amelanotic, and cystic nevi, each with distinct features observed during clinical examination.

Pigmented

The most common form, pigmented conjunctival nevi contain melanin, giving them a brown, tan, or black coloration. Pigmentation varies among individuals and may darken over time, particularly during puberty. These nevi are typically well-circumscribed and slightly elevated, often appearing near the limbus. Under slit-lamp examination, they may reveal small cystic spaces, a hallmark of benignity. While pigmentation changes can occur, rapid darkening or irregular pigmentation warrants further evaluation to rule out malignant transformation.

Amelanotic

Lacking significant melanin, amelanotic conjunctival nevi appear pale, pink, or nearly colorless, making them more difficult to identify. Despite their subtle presentation, they share the benign characteristics of pigmented nevi, including well-defined borders and slow growth. Their lack of pigmentation can cause confusion with other conjunctival lesions, such as papillomas or inflammatory growths. Slit-lamp examination remains essential for distinguishing amelanotic nevi, as they often contain cystic spaces similar to their pigmented counterparts. Though less common, these nevi should be monitored for structural changes, particularly if vascularization or surface irregularities develop.

Cystic

Cystic conjunctival nevi contain multiple translucent or fluid-filled spaces, visible under slit-lamp examination. These cysts are a defining characteristic of benign conjunctival nevi and help differentiate them from more concerning lesions, such as melanoma. While cystic nevi can be pigmented or amelanotic, the presence of cysts is a reassuring feature. These lesions typically remain stable, though minor fluctuations in size may occur due to fluid dynamics. Regular monitoring is recommended, but intervention is rarely needed unless cosmetic concerns or significant enlargement arise.

Diagnostic Approaches

Evaluating a conjunctival nevus in a child requires clinical observation, imaging techniques, and, in select cases, histopathological analysis. A slit-lamp examination is the primary method for assessing the lesion’s size, shape, pigmentation, and structural features. This high-magnification inspection allows ophthalmologists to identify benign characteristics such as discrete borders, smooth surface texture, and cystic spaces. Serial photography is often used to track subtle changes over time.

When additional evaluation is needed, anterior segment optical coherence tomography (AS-OCT) provides a detailed cross-sectional view of the lesion, revealing internal cystic structures and lesion depth. AS-OCT is particularly useful for assessing amelanotic or irregularly pigmented nevi. In rare cases, ultrasound biomicroscopy (UBM) may be used to evaluate deeper structures.

If suspicion for malignant transformation arises—such as rapid enlargement, irregular vascularization, or loss of well-defined borders—a biopsy may be considered. Histopathological analysis distinguishes benign nevi from conjunctival melanoma or other proliferative lesions. However, due to the overwhelmingly benign nature of conjunctival nevi in children, invasive procedures are generally avoided unless significant changes occur.

Distinctions From Other Conjunctival Growths

Conjunctival nevi must be differentiated from other conjunctival growths with similar characteristics. Conjunctival papillomas, for instance, can appear slightly raised with a smooth surface but often have a more lobulated texture and are associated with human papillomavirus (HPV) infection. Unlike nevi, papillomas tend to grow more rapidly and may exhibit vascularization, making them more prone to irritation or spontaneous bleeding. Their tendency to develop on the palpebral conjunctiva or fornices rather than near the limbus also aids in differentiation.

Pyogenic granulomas, another type of conjunctival lesion, can resemble nevi due to their raised profile. However, these growths arise from reactive blood vessel proliferation, often following trauma, surgery, or chronic inflammation. Their rapid onset, bright red coloration, and tendency to bleed distinguish them from the slow-growing, well-circumscribed nature of conjunctival nevi. Similarly, limbal dermoids—benign congenital lesions composed of collagen and other tissue elements—may appear as pale or yellowish conjunctival masses but are typically firmer in consistency and lack the cystic spaces characteristic of nevi.

Factors Associated With Pediatric Cases

The development of conjunctival nevi in children is influenced by genetic predisposition, hormonal changes, and environmental factors. While often congenital or appearing in early childhood, they may not become noticeable until later years as pigmentation increases. Familial tendencies suggest a hereditary component, with children of parents with ocular or cutaneous nevi having a higher likelihood of developing similar lesions.

Hormonal fluctuations, particularly during puberty, play a significant role in pigment changes. Increased melanin production can cause nevi to darken, a well-documented phenomenon in both dermatology and ophthalmology. While sun exposure is known to affect skin pigmentation, its impact on conjunctival nevi remains less clear. Some research suggests ultraviolet (UV) radiation may contribute to pigmentation variations, though these nevi generally receive less direct sun exposure than skin lesions. Ophthalmologists may recommend UV-blocking eyewear, particularly for children with fair skin or a predisposition to pigmentation disorders.