There are various types of Coloboma, contingent upon which some portion of the eye is absent. Coloboma can be inherited or can occur spontaneously. This is a congenital defect that affects the normal structures of the eye, most commonly the eyelid or the iris.
This Disease involving the retina result in vision loss in specific parts of the visual field. Colobomas might be available in one or the two eyes and, contingent upon their size and area, can influence an individual’s vision.
Coloboma is an eye abnormality that occurs before birth. Colobomas involving the eyeball should be distinguished from gaps that occur in the eyelids.
How Many types of coloboma?
- Iris Coloboma
- Eyelid Coloboma
- Lens Coloboma
- Macular Coloboma
- Optic Nerve Coloboma
- Uveal Coloboma
- Chorioretinal Coloboma
Now, we are going to detail discuss about types of Coloboma.
The iris is the front most piece of the uvea (center layer of the eye). Coloboma can influence your iris, the tissue that gives you your eye shading. A coloboma is an opening in one of the structures of the eye, for example, the iris.
Clinical features of the iris coloboma are:
- Blurry vision
- Monocular diplopia
- Absence of sectoral iris tissue
- Often associated with cataract
Iris coloboma is likely to cause light sensitivity in bright conditions. Light sensitivity and glare can cause discomfort and affect the quality of vision. Your pupil may look oval if the coloboma is partial, but if more of your lower iris is missing, your pupil will look more keyholes shaped.
The two kids and grown-ups with just iris coloboma will most likely have genuinely great vision. The iris has the characteristic “keyhole” shape. These normally leave the vision unchanged. Coloboma influences just the edge of the student, making it seem oval instead of round.
The most common position of Eylid Coloboma is at the junction of the medial and middle third of the upper lid. Eyelid coloboma is an unprecedented, one-sided or reciprocal, incomplete or full-thickness eyelid deformity. In eyelid coloboma a piece of either the upper or lower eyelid is missing.
Eyelid coloboma might be a piece of a hereditary disorder or occur because of a disturbance of eyelid advancement in an infant. An eyelid coloboma is a full-thickness imperfection of the eyelid. Eyelid coloboma can occur in many locations. It is brought about by disappointment of combination of the mesodermal top folds.
Treat Eyelid Coloboma:
Surgery in an eyelid coloboma is mainly for cosmesis and corneal protection. If small, then the cornea is protected with ocular lubricants till it is a little older. If large, immediate surgery is required to close the defect.
In Lens coloboma, a piece of the lens is missing. The focal point, which enables spotlight to light on the retina, will normally show up with a score. On the off chance that the focal point of the eye is influenced by coloboma, vision is influenced in light of the adjustment fit as a fiddle brought about by a score or scratch.
There may also be some degree of cataract in the affected eye, that’s why the lens is cloudy instead of being clear. This cloudiness can cause symptoms such as blurred or misty vision, colors appearing dull and glare in your vision.
Treat Iris coloboma:
Contact lenses may be used to improve the cosmetic appearance of a coloboma, and to rid the patient of unwanted symptoms. If the patient is undergoing any intraocular surgery then repair of the iris may be done at the same time.
Coloboma of Macula is a rare, non-syndromic developmental defect of the eye characterized by well-circumscribed. Macular coloboma is characterised by a sharply defined, rather large defect in the central area of the fundus that is oval or round, and coarsely pigmented. Macular coloboma might be caused when typical eye advancement is hindered or following an irritation of the retina during improvement of the infant.
Currently, no risk factors have been clearly identified for Macular Coloboma. This happens when the focal point of the retina, called the macula, does not grow regularly. Macular Coloboma may be seen in association with the Down syndrome and certain bone disorders and kidney disorders. The macula is responsible for daylight, fine and color vision. Macular colobomas, usually bilateral, are the major ocular feature of this oculoskeletal disorder.
Optic Nerve Coloboma
Colobomas of the optic nerve usually occur bilaterally. Coloboma of the optic nerve is an innate irregularity of the optic plate where there is a deformity of the second rate part of the optic nerve. The condition may occur in one or both eyes. Therefore, The optic nerve cups are frequently enormous and may have leftover glial tissue in them.
Optic nerve is burrowed out, diminishing vision. The optic nerve is the heap of nerve filaments that transfers the light flag from the eye to the mind. An uveal coloboma that is huge enough to include the optic nerve, either the sub-par divide or the whole optic plate.
Uveal colobomas are a rare entity; they are present in our milieu. Uveal colobomas are a congenital malformation that is secondary to a failure in the closure of the embryonic optic fissure. The unea is the middle layer of the eye. This Disease can affect the iris, the colored part of the eye, giving it a distinct keyhole or cat-eye appearance. Uveal coloboma-cleft lip and palate-intellectual disability is characterize by coloboma of the iris, bilateral cleft lip and palate, and intellectual deficiency of varying degree.
It is believe that uveal coloboma is primarily genetic in origin. Patients with uveal coloboma ought to have yearly follow-up tests by an eye care proficient. There is at present no drug or medical procedure that can fix or turn around coloboma and make the eye entire once more.
Chorioretinal coloboma is an uncommon congenital anomaly of the posterior segment occurring as a consequence of incomplete closure of the embryonic fissure during fetal development. In the chorioretinal coloboma, part of the retina is missing. Chorioretinal colobomas are cause by failure of the embryonic fissure to close during development.
Clinical features of the Chorioretinal coloboma is Chorioretinal coloboma depend on the location of the coloboma and ocular structures involved. Chorioretinal coloboma typically located in inferotemporal area.
It can be unilateral or bilateral. It May extend and involve the macula. Chorioretinal coloboma Maybe associate with coloboma of other ocular structures along the embryonic fissure i.e. optic nerve, iris or lid.
Above all, 7 types of Coloboma disease.