Mechanism of steroid induced glaucoma is –
**Core Concept**
Steroid-induced glaucoma, also known as secondary open-angle glaucoma, is a condition where the intraocular pressure (IOP) increases due to prolonged use of corticosteroids. This condition is often seen in patients on long-term corticosteroid therapy, either topically or systemically. The mechanism behind steroid-induced glaucoma is multifactorial, involving changes in the trabecular meshwork and aqueous humor dynamics.
**Why the Correct Answer is Right**
The mechanism of steroid-induced glaucoma involves the suppression of aqueous humor outflow through the trabecular meshwork. Corticosteroids inhibit the expression of the enzyme lactate dehydrogenase (LDH), which in turn reduces the production of prostaglandins and other inflammatory mediators. These mediators normally help to maintain the integrity of the trabecular meshwork and facilitate aqueous humor outflow. With reduced prostaglandin production, the trabecular meshwork becomes more rigid and less permeable, leading to decreased aqueous humor outflow and increased IOP.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not accurately describe the mechanism of steroid-induced glaucoma. While corticosteroids can affect aqueous humor production, the primary mechanism of steroid-induced glaucoma is related to decreased outflow through the trabecular meshwork.
**Option B:** This option is incorrect as it is a mechanism of glaucoma associated with angle-closure glaucoma, not steroid-induced glaucoma.
**Option C:** This option is incorrect as it describes a mechanism of glaucoma associated with pigment dispersion syndrome, not steroid-induced glaucoma.
**Clinical Pearl / High-Yield Fact**
Steroid-induced glaucoma can occur within weeks to months after starting corticosteroid therapy, and the risk is higher in patients with a family history of glaucoma. Monitoring IOP regularly is crucial in patients on long-term corticosteroid therapy.
**Correct Answer: C. Suppression of aqueous humor outflow through the trabecular meshwork.**