Introduction
Fibrosis is a mechanism of the body's response to certain trauma or impacts. It can develop anywhere in the body. When it develops in the eyes, it can bring about various ocular complications by interrupting the path of vision.
What Is Ocular Fibrosis?
Fibrosis is a form of reaction the body exhibits following trauma or impact. Tissue injury or abrasion is often followed by a sequence of steps that eventually lead to fibrosis in the area. Like other bodily areas, this fibrosis may also arise in the eyes, technically known as ocular fibrosis. The human eyes are highly sophisticated and organized; hence, they cannot afford any changes in the cells or vasculature (blood supply). Fibrosis in the eyes creates a hindrance to the visual axis. It significantly impacts the vision in diverse ways and reflects in the form of numerous eye disorders.
What Causes Ocular Fibrosis?
Fibrosis in the eye is an obstacle to light transmission through the eyes. Only when the light traversed through the cornea reaches the retina and acts on the photoreceptor cells (light-sensitive cells), the impulse for the vision gets generated, which the brain perceives (recognizes). Finally, facilitating the vision. In the case of fibrosis, the light could not pass unhindered to the retina, thus impacting the vision greatly. A wide variety of factors could result in fibrosis in the eyes. Some of the leading causes of ocular fibrosis include the following:
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Infections: Certain eye infections damage the delicate ocular cells, resulting in fibrosis. Post-infectious conjunctivitis is also associated with ocular fibrosis, typically in the corneal region.
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Trauma: Any form of impact or injury to the eye results in tissue damage. Whenever tissue damage and bleeding occur in any of the delicate eye tissues, as in other bodily areas, healing occurs in the eye, healing is often accompanied by the formation of scars which eventually progress into fibrosis.
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Immune-Mediated Injury: Any inflammation or injury in the eye mediated by the immune cells often give rise to fibrosis. Autoimmune conditions like ocular mucous membrane pemphigoid (OMMP) also manifest scarring and extensive fibrosis in the conjunctiva (conjunctival scarring).
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Metabolic Injury: Injury to the optic cells induced by certain metabolic disorders may also reflect in the form of ocular fibrosis.
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Burn Injuries: Scarring and fibrosis develop from thermal and chemical burns.
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Ischemia: When the blood flow to the eye is significantly impaired due to underlying conditions, it gives rise to death and injury to the cells. Ischemia is the medical term that stands for compromised blood flow. Injury and reduced oxygen levels trigger the formation and growth of new blood-supplying units (neovascularization), which potentially give rise to scarring and fibrosis.
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Surgical Complications: Surgical treatments in the eyes always carry the potential risk of developing scarring and fibrosis.
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Congenital: At times, fibrosis develops due to inborn (by birth) conditions or defects like congenital extraocular muscle fibrosis.
What Are the Symptoms Associated With Ocular Fibrosis?
Ocular fibrosis does not exhibit wide-ranging symptoms; most of its signs and symptoms are limited to visual changes. Scarring leads to cloudiness and makes the vision foggy, blurred, and dim. Severe fibrosis may even end up in complete loss of eyesight.
What Are the Different Types of Ocular Fibrosis?
Based on the site in which the fibrosis develops in the eyes, ocular fibrosis can be categorized into the following:
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Fibrotic Disorders Developing in the Anterior Section of the Eye: Fibrosis develops in the front segment of the eye involving the sclera, conjunctiva, and cornea. It encompasses certain eye disorders like glaucoma and corneal opacification. The fibrosis of the drainage meshwork in the eye may lead to fluid drainage disruption, eventually leading to glaucoma (open-angle glaucoma). Trachoma and trichiasis infections caused by chlamydia trachomatis often result in conjunctival scarring and fibrosis.
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Fibrotic Disorders Developing in the Posterior Section of the Eyes: Posterior section encompasses the structures afterward the eye lens. Fibrotic disorders affecting those areas include epiretinal, retinal, and sub-retinal fibrosis. Retinal fibrosis has got severe implications for the vision of a person. Abnormalities in the retinal structure manifest as bleeding, swelling, and eventually resulting in cicatrization (scar). Epiretinal fibrosis is more or less associated with diabetic retinopathy, significantly lowering oxygen levels and bleeding. It often ends up in the growth of new blood vessels, paving the way for fibrosis.
What Are the Diagnostic Procedures Used for the Detection of Ocular Fibrosis?
Detailed medical history and clinical findings are insufficient for the diagnosis. In addition, physical examination and specific diagnostic techniques are undertaken to identify the type, site, and severity of the fibrosis.
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Slit Lamp Examination: It facilitates eye visualization in all three dimensions, especially the anterior segment. Fibrosis in this segment can be easily recognized with the help of slit lamp examination.
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Optical Coherence Tomography: It provides a clear picturization of the retina, thus, enhancing the detection of fibrosis in the retinal area.
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Optical Coherence Tomography Angiography: It combines the optical coherence tomography technique to visualize blood vessels. So that any irregularities or changes in the optic blood vessel can be easily spotted.
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Retinal Fundus Photography: Retinal areas of bleeding, scarring, trauma, and many more can be sighted by this technique.
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Second Harmonic Generation (SHG) Imaging: It is a novel technique extensively adopted for detecting corneal fibrosis.
What Are the Available Treatment Interventions for Ocular Fibrosis?
Ocular fibrosis is a potentially impairing condition. The treatment strategy is influenced by the underlying factors that lead to fibrosis, the location, and the intensity of fibrosis. However, there are not many successful treatment strategies for correcting ocular fibrosis. Antimetabolites are the sole approved treatment strategy that is available as of now. Numerous research is ongoing to establish newer treatment modalities for ocular fibrosis.
Conclusion
Ocular fibrosis dramatically impacts the quality of life as it can lead to complete impairment of eyesight. It holds a significant position among the diseases that potentially affect vision. Even though the conditions are reported frequently, they still lack efficacious and fruitful treatment interventions. The upcoming years will witness novel interventions to tackle ocular fibrosis.
