Keratoglobus (from

Greek Greek may refer to: 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 of all kno ...

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

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

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

eye An eye is a sensory organ that allows an organism to perceive visual information. It detects light and converts it into electro-chemical impulses in neurons (neurones). It is part of an organism's visual system. In higher organisms, the ey ...

in which structural changes within the

cornea The cornea is the transparency (optics), transparent front part of the eyeball which covers the Iris (anatomy), iris, pupil, and Anterior chamber of eyeball, anterior chamber. Along with the anterior chamber and Lens (anatomy), lens, the cornea ...

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, but that does not have to be straight. Intuitively, a curve may be thought of as the trace left by a moving point. This is the definition that ...

. 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 (: diagnoses) is the identification of the nature and cause of a certain phenomenon. Diagnosis is used in a lot of different academic discipline, disciplines, with variations in the use of logic, analytics, and experience, to determine " ...

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 or vision impairment (VI or VIP) is the partial or total inability of visual perception. In the absence of treatment such as corrective eyewear, assistive devices, and medical treatment, visual impairment may cause the individual difficul ...

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 prognosis continues to be variable, 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 is an eye disorder in which the cornea, the transparent front part of the eye, gradually thins and bulges outward into a cone shape. This causes distorted vision, including blurry vision, double vision, increased nearsightedness, ...

, 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 dy ...

of the cornea. Similar to

it is typically diagnosed in the patient's

adolescent Adolescence () is a transitional stage of human physical and psychological development that generally occurs during the period from puberty to adulthood (typically corresponding to the age of majority). Adolescence is usually associated w ...

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