All of the following is true regarding blindness except –
**Blindness**
### Core Concept
Blindness is a condition characterized by severe visual impairment, typically defined as a visual acuity of less than 20/400 in the better eye with correction. The causes of blindness can be congenital, acquired, or age-related, and may involve damage to the retina, optic nerve, or other parts of the visual pathway.
### Why the Correct Answer is Right
* The correct answer to this question is: **C.**
* This option is incorrect because blindness can indeed be caused by **intraocular pressure** associated with glaucoma, which is a leading cause of irreversible vision loss worldwide.
* Glaucoma is characterized by increased intraocular pressure, which damages the optic nerve and can lead to blindness if left untreated.
### Why Each Wrong Option is Incorrect
**Option A:** This option is incorrect because **cataracts** are a common cause of blindness, particularly in older adults. They can be treated with surgery, but if left untreated, can lead to severe vision loss.
**Option B:** This option is incorrect because **diabetic retinopathy** is a leading cause of blindness in working-age adults. It is a complication of diabetes that damages the blood vessels in the retina, leading to vision loss.
### Clinical Pearl / High-Yield Fact
It is essential for clinicians to recognize the signs and symptoms of blindness-causing conditions, such as glaucoma, cataracts, and diabetic retinopathy, to provide timely intervention and prevent irreversible vision loss.
### Correct Answer: C. Intraocular pressure is not a direct cause of blindness.