As an expert in the field of ophthalmology, I can provide you with a detailed explanation of how keratitis is spread. Keratitis is an inflammation of the cornea, which is the clear, protective outer layer covering the front of the eye. It can be caused by various factors, including infections, injuries, or exposure to harmful substances. The spread of keratitis can occur through several mechanisms, which I will outline below. Infectious Agents The most common cause of keratitis is an infection. Bacteria, viruses, fungi, and parasites can all cause this condition. The spread of these infectious agents can occur in several ways: 1. Direct Contact: This is one of the primary methods of transmission. Touching the eye with contaminated hands or objects can introduce the infectious agent directly into the eye. 2. Ocular Trauma: Injuries to the eye, such as from foreign bodies like dust, sand, or even a fingernail scratch, can break the cornea's protective barrier, allowing pathogens to enter. 3. Contaminated Water: Swimming in water that is contaminated with bacteria or other microorganisms can lead to an increased risk of developing keratitis, especially if the individual has a pre-existing corneal abrasion or a compromised immune system. 4. Poor Contact Lens Hygiene: Improper cleaning and storage of contact lenses can lead to the growth of harmful microorganisms on the lens surface. Wearing these contaminated lenses can cause an infection. 5. Airborne Transmission: In some cases, especially with viral infections, the infectious agent can be spread through the air, although this is less common for keratitis. Non-Infectious Causes While the focus is often on infectious causes, it's important to note that keratitis can also result from non-infectious factors: 1. Exposure to Chemicals: Accidental exposure to harmful chemicals can cause a chemical burn to the cornea, leading to keratitis. 2. Dry Eye Syndrome: Chronic dry eye can lead to inflammation and damage to the cornea, which may present similarly to infectious keratitis. 3. Autoimmune Diseases: Conditions like rheumatoid arthritis can cause keratitis as part of a systemic autoimmune response. 4. Prolonged Use of Eye Medications: Some eye drops or ointments, particularly those with steroids, can suppress the immune response and increase the risk of developing keratitis. Consequences of Untreated Keratitis If left untreated, infectious keratitis can have serious consequences. As you mentioned, it can progress through the entire thickness of the cornea, potentially involving the neighboring sclera. This can lead to the spread of the infection inside the eyeball, which may result in perforation of the eye and the possible loss of the eye. Prevention and Treatment Prevention of keratitis involves maintaining good eye hygiene, avoiding touching the eyes with dirty hands, and using proper contact lens care. Treatment depends on the cause and may include antibiotics, antiviral, or antifungal medications for infectious keratitis, or addressing the underlying cause in non-infectious cases. In conclusion, understanding the various ways in which keratitis can spread is crucial for prevention and early intervention. Prompt treatment is key to avoiding the serious complications associated with this condition. read more >>

Infectious keratitis that is not promptly treated can progress through the entire thickness of the cornea, or begin to involve neighboring sclera, possibly leading to spread of infection inside the eyeball or perforation, or both, and possible loss of the eye.read more >>