Coloboma of optic nerve or Morning Glory syndrome

Definition

Coloboma of optic nerve or Morning Glory syndrome is a rare defect of the optic nerve that causes moderate to severe blindness.
Morning Glory syndrome is a congenital anomaly of the optic disc in which there is a funnel-shaped excavation of the posterior fundus incorporating the optic nerve, surrounded by an elevated annulus of chorioretinal pigment.The issue stems from an undeveloped optic nerve: while in utero, the nerve ending from the eye never reached the nerve ending from the brain. A central core of white glial tissue occupies the position of the normal optic cup, causing a white mass. When a picture is taken of the eye, this white mass stands out apart from the veins of the eyes, looking very much like the center of a Morning glory flower. Reflection from within the eye may give the appearance of a white pupil, due to the lack of the "black" optic nerve mass, although this "clouded pupil" cannot be used to diagnose the disease. Morning Glory Syndrome typically affects only one eye; but cases has been documented of bilateral Morning Glory Syndrome (those with that stage of severe blindness have other disorders as well, like autism. Also, this syndrome is different from an optic disc injury, as the disorder is present at birth and not developed later in life. Young girls are twice as likely to be diagnosed with this disorder, pointing toward the possibility of a genetic connection.

Effects

Vision in the affected eye is severely impaired, depending on the completed development of the optic nerve. More mild cases cause limited depth or colorperception, while the most severe cause total blindness. Full use of the affected eye is never gained. The most common side effect of this disorder is eyestrain from overuse of the un-affected eye. Also, there is an increased risk of serious retinal detachment, manifesting in 1/3 of patients. If retinal detachment does occur, it is usually not correctable and all sight is lost in the affected eye.

Diagnosis

The first noticeable signs of the syndrome usually do not appear until after the first twelve months of the child's life. The child usually has severe balance issues as he or she learns to sit or walk, often leaning or tilting the head toward the good eye to correct the brain's skewed perception of the world. Often the child will fall in the same direction while walking or run into objects that are placed on his or her blind side. The child will also develop a "lazy eye", or an eye that drifts severely away from the child's fixed point of reference. This syndrome must be confirmed through pupillary dilation and examination of the optic disc, as the signs alone will not constitute a diagnosis.

Children with Morning Glory live relatively normal lives, even those who have discolored or lazy pupils. Although non-prescription glasses should be worn for eye protection, this syndrome does not usually prevent the individual from living a normal life, driving cars, playing sports, reading, etc. Certain activities, such as gymnastics and ice skating, may be more difficult for patients with Morning Glory due to a compromised view of the world and skewed sense of balance, but they are still possible. Like most other eye conditions, a diagnosis of Morning Glory precludes a person from certain occupations, such as being a baseball player orfighter pilot.