VITAMIN A DEFICIENCY IN POSTERIOR SEGMENT OF THE EYES

 

Oparaku Divine.

The posterior segment or posterior cavity is the back two-thirds of the eye that includes the anterior hyaloid membrane and all of the optical structures behind it: the vitreous humor, retina, choroid, and optic nerve. The portion of the posterior segment is visible during ophthalmoscopy (or fundoscopy) is sometimes referred to as the posterior pole, or fundus. Some ophthalmologists specialize in the treatment and management of posterior segment disorders and diseases. 

Your risk of developing an eye disease increases as you get older, but most of the eye disease is as a result to deficiency of some essential nutrient that are vital and very important to the health of the system. Lack of some essential vitamins and supplements could cause damages to the posterior segment of the eye, examples are: Vitamin A: Vitamin A deficiency is one of the most common causes of blindness in the world. This vitamin is essential for maintaining your eyes’ light-sensing cells, also known as photoreceptors. If you don’t consume enough vitamin A, you may experience night blindness, dry eyes, or even more serious conditions, depending on the severity of your deficiency. Vitamin A is only found in animal-derived foods. 

The richest dietary sources include liver, egg yolks, and dairy products. However, you can also get vitamin A form antioxidant plant compounds called pro vitamin A carotenoid, found in high amounts in some fruits and vegetables. 

Pro vitamin A carotenoids provide around 30% of people’s vitamin A requirement, on average. The most efficient of them is betacarotene, which is found in high amounts in kale, spinach, and carrots.

 Deficiency

Keratomalacia: Which is common in badly nourished children who are lacking vitamin A, the condition is bilateral. This cause the cornea to become dull, insensitive, soft and opaque. Secondary infection, hypopyon and perforating ulceration are common. 

Xerophthalmia (xerosis): Characterized by small triangular white patches on the outer and inner side of the cornea, covered by the material resembling dried foam, which is not wetted by tears, in this case the cornea looses luster. 

Nyctalopia (Avitaminosis): Causes night blindness resulting from vitamin A deficiency Hypervitaminosis: Vitamin A intoxication known to produce intracranial hypertension with bilateral papilledema, which may resolve months after ingestion of the vitamin A has ceased.