Laser iridotomy is useful in
**Core Concept**
Laser iridotomy is a surgical procedure used to create a small hole in the iris to improve the drainage of aqueous humor from the anterior chamber of the eye. This procedure is primarily used to treat conditions characterized by increased intraocular pressure (IOP) and decreased aqueous outflow.
**Why the Correct Answer is Right**
The correct procedure for laser iridotomy involves using a laser to create a small hole in the iris, allowing for increased aqueous outflow and subsequently reducing IOP. This is particularly useful in conditions such as acute angle-closure glaucoma, where the iris is positioned too close to the trabecular meshwork, impeding aqueous outflow. The laser iridotomy procedure helps to alleviate this obstruction, thereby reducing IOP and preventing further damage to the optic nerve.
**Why Each Wrong Option is Incorrect**
**Option A:** Laser iridotomy is not typically used to treat conditions with normal IOP or open-angle glaucoma, as these conditions do not involve significant obstruction of aqueous outflow.
**Option B:** Laser trabeculoplasty is a different procedure that involves stimulating the trabecular meshwork to improve aqueous outflow, and is not related to laser iridotomy.
**Option C:** Laser iridotomy is not used to treat posterior segment diseases, such as retinal detachment or macular degeneration, which require different treatments.
**Clinical Pearl / High-Yield Fact**
A key indication for laser iridotomy is acute angle-closure glaucoma, which requires prompt treatment to prevent permanent vision loss. This condition can be precipitated by factors such as hyperopia, pupil dilation, or anatomical abnormalities.
**Correct Answer:** C. Laser iridotomy is useful in conditions characterized by acute angle-closure glaucoma.