Summary about Disease
Keratoglobus is a very rare, non-inflammatory, degenerative corneal ectasia characterized by a global thinning of the cornea, resulting in a spherical protrusion of the entire cornea. This distinguishes it from keratoconus, where the thinning is localized. It is often bilateral and can lead to significant visual impairment.
Symptoms
Significant blurring of vision
Severe nearsightedness (myopia) and astigmatism
Pronounced corneal protrusion
Increased risk of corneal rupture with minor trauma
Eye irritation
Glare and halos around lights
Causes
The exact cause of keratoglobus is not fully understood, but it is believed to be related to:
Genetic factors: Often associated with Ehlers-Danlos syndrome, brittle cornea syndrome and Leber congenital amaurosis. Familial cases have been reported.
Enzyme deficiencies: Possible alterations in collagen metabolism.
Congenital weakness: An inherent weakness in the corneal structure from birth.
Eye rubbing: Can accelerate corneal thinning.
Medicine Used
There is no specific medicine to "cure" keratoglobus. Treatment focuses on managing the symptoms and preventing further progression:
Eyeglasses or contact lenses: For correcting refractive errors (myopia and astigmatism) in mild cases.
Scleral lenses: These are large, rigid gas permeable lenses that vault over the cornea, providing a smooth refractive surface and protecting the weakened cornea.
Corneal cross-linking (CXL): While primarily used for keratoconus, it may be considered in some cases of keratoglobus to strengthen the cornea, although evidence is limited.
Corneal transplantation (Penetrating Keratoplasty or Deep Anterior Lamellar Keratoplasty - DALK): May be necessary in severe cases with significant corneal thinning or rupture.
Is Communicable
Keratoglobus is not communicable. It is not caused by a virus, bacteria, or any other infectious agent and cannot be spread from person to person.
Precautions
Avoid eye rubbing: Rubbing can worsen corneal thinning and increase the risk of rupture.
Protective eyewear: Wear protective glasses or goggles during activities with a risk of eye injury.
Regular eye exams: Frequent monitoring by an ophthalmologist is crucial to track the progression of the disease.
Genetic counseling: If there is a family history of keratoglobus or related conditions, genetic counseling may be beneficial.
How long does an outbreak last?
Keratoglobus is not an "outbreak"-related disease. It is a chronic condition that progresses over time. There isn't a specific "outbreak" period; instead, the condition gradually worsens.
How is it diagnosed?
Diagnosis is typically made by an ophthalmologist through a comprehensive eye exam, including:
Slit-lamp examination: To assess the corneal shape and thickness.
Corneal topography: Maps the curvature of the cornea.
Pachymetry: Measures corneal thickness.
Refraction: To determine the degree of refractive error (myopia and astigmatism).
Optical coherence tomography (OCT): Provides detailed images of the corneal structure.
Timeline of Symptoms
The progression of keratoglobus varies from person to person. However, a general timeline could be:
Early Stages: Mild blurring of vision, increasing nearsightedness and astigmatism.
Middle Stages: Noticeable corneal protrusion, increased glare and halos, worsening vision.
Late Stages: Significant corneal thinning, high risk of corneal rupture, severe vision impairment.
Important Considerations
Prompt Diagnosis: Early diagnosis and management are crucial to prevent complications.
Corneal Rupture Risk: Keratoglobus significantly increases the risk of corneal rupture from even minor trauma.
Individualized Treatment: Treatment plans should be tailored to the individual's condition and stage of the disease.
Associated Conditions: It's important to investigate for underlying systemic conditions like Ehlers-Danlos syndrome.
Surgical Risks: Corneal transplantation in keratoglobus can have a higher risk of complications compared to other corneal conditions.