Chorioretinal lacunae are areas of thinning or atrophy in the choroid and retinal pigment epithelium (RPE), layers supporting the retina at the back of the eye. This article explains what they are, their causes, and how they can affect vision.
What Are Chorioretinal Lacunae
Chorioretinal lacunae are distinct, punched-out lesions in the pigmented layer of the retina, often found around the optic disc. These areas represent a loss or thinning of tissue in the choroid and the retinal pigment epithelium (RPE), layers located beneath the light-sensing retina.
The choroid is a vascular layer providing oxygen and nutrients to the outer retina, while the RPE helps maintain retinal health by absorbing scattered light and nourishing photoreceptor cells.
When lacunae form, the tissue in these supporting layers becomes atrophied or absent, exposing the underlying sclera, the white outer layer of the eye. This absence of pigment results in their typical appearance as pale, depigmented areas that can be white or yellowish. They are well-circumscribed and can vary in size and number, ranging from small, isolated spots to larger, confluent patches. The lesions are full-thickness defects limited to the RPE and choroid, with the overlying retina typically remaining intact.
Underlying Causes
Chorioretinal lacunae can arise from various underlying causes, broadly categorized as congenital or acquired. Congenital lacunae are present at birth and often result from developmental anomalies during fetal eye formation. A notable example is Aicardi syndrome, a rare neurodevelopmental disorder where chorioretinal lacunae are a consistent feature.
Acquired causes develop later in life due to external factors or disease processes. Past infections are a common acquired cause; for instance, toxoplasmosis or histoplasmosis can lead to inflammation that damages the choroid and retina, resulting in lacunae as the inflammation resolves and tissue atrophies.
Severe trauma to the eye can also cause localized tissue damage and subsequent lacunae. Additionally, high myopia, or severe nearsightedness, can lead to lacunae due to the extreme stretching and thinning of the ocular tissues, including the choroid and retina, as the eyeball elongates.
How They Affect Vision
Many individuals with chorioretinal lacunae may experience no noticeable visual symptoms, particularly if the lacunae are small or located away from the central macula. The macula is the part of the retina responsible for sharp, detailed central vision. If the lacunae are situated in the peripheral retina, their presence may not affect daily visual tasks.
However, if chorioretinal lacunae affect critical areas, particularly the macula or the optic nerve head, visual symptoms can occur. These symptoms may include blurred vision, which can range from subtle to significant depending on the size and location of the lesion. Individuals might also experience blind spots, known as scotomas, where a portion of their visual field is missing. Reduced visual acuity, meaning the sharpness of vision, can also be a consequence, especially if the central fovea—the most sensitive part of the macula—is involved.
Diagnosis and Ongoing Care
The diagnostic process for chorioretinal lacunae involves a comprehensive eye examination performed by an ophthalmologist. Ophthalmoscopy, where the doctor looks into the back of the eye, is used to visualize the retina and choroid. The characteristic pale, depigmented areas of lacunae are typically identifiable.
To further assess and monitor the condition, imaging techniques are employed. Fundus photography captures detailed images of the back of the eye, providing a baseline record. Optical coherence tomography (OCT) offers cross-sectional views of the retinal layers, allowing for precise evaluation of tissue thinning and atrophy.
There is no direct treatment to reverse lacunae once formed. Management focuses on monitoring the condition for any changes or potential complications. This includes addressing any underlying treatable causes, such as active infections, or managing secondary complications. Regular follow-up appointments with an ophthalmologist are important to track the stability of the lacunae and maintain overall eye health.