Keratoglobus (from

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

: ''kerato-'' horn, cornea; and

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

: ''globus'' round) is a degenerative non- inflammatory disorder of the

eye Eyes are organs of the visual system. They provide living organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and conv ...

in which structural changes within the

cornea The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical power ...

cause it to become extremely thin and change to a more globular shape than its normal gradual

curve In mathematics, a curve (also called a curved line in older texts) is an object similar to a line (geometry), line, but that does not have to be Linearity, straight. Intuitively, a curve may be thought of as the trace left by a moving point (ge ...

. It causes corneal thinning, primarily at the margins, resulting in a spherical, slightly enlarged eye. It is sometimes equated with "megalocornea".

Pathophysiology

Keratoglobus is a little-understood disease with an uncertain cause, and its progression following

diagnosis Diagnosis is the identification of the nature and cause of a certain phenomenon. Diagnosis is used in many different disciplines, with variations in the use of logic, analytics, and experience, to determine " cause and effect". In systems engin ...

is unpredictable. If afflicting both eyes, the deterioration in vision can affect the patient's ability to drive a car or read normal print. It does not however lead to

blindness Visual impairment, also known as vision impairment, is a medical definition primarily measured based on an individual's better eye visual acuity; in the absence of treatment such as correctable eyewear, assistive devices, and medical treatment� ...

Treatment

Treatment includes the use of protective eye glasses. A number of surgical options are also available. Further progression of the disease usually leads to a need for

corneal transplantation Corneal transplantation, also known as corneal grafting, is a surgical procedure where a damaged or diseased cornea is replaced by donated corneal tissue (the graft). When the entire cornea is replaced it is known as penetrating keratoplasty a ...

because of extreme thinning of the cornea. Primarily, large size penetrating keratoplasty has been advocated. Recent additions of techniques specifically for keratoglobus include the "tuck procedure", whereby a 12 mm corneo-scleral donor graft is taken and trimmed at its outer edges. A host pocket is formed at the limbal margin and the donor tissue is "tucked" into the host pocket.

Prognosis

Keratoglobus continues to be a somewhat mysterious disease, but it can be successfully managed with a variety of clinical and surgical techniques. The patient is at risk for globe perforation because the thinned out cornea is extremely weak.

Epidemiology

It is a much rarer condition than

keratoconus Keratoconus (KC) is a disorder of the eye that results in progressive thinning of the cornea. This may result in blurry vision, double vision, nearsightedness, irregular astigmatism, and light sensitivity leading to poor quality-of-life. Usu ...

, which is the most common

dystrophy Dystrophy is the degeneration of tissue, due to disease or malnutrition, most likely due to heredity. Types * Muscular dystrophy ** Duchenne muscular dystrophy ** Becker's muscular dystrophy ** Myotonic dystrophy * Reflex neurovascular dystrop ...

of the cornea. Similar to

it is typically diagnosed in the patient's adolescent years and attains its most severe state in the twenties and thirties.

References

External links

{{Congenital malformations and deformations of eye, ear, face and neck Congenital disorders of eyes