## **Core Concept**
Secondary glaucoma refers to increased intraocular pressure (IOP) due to another ocular or systemic condition. Intractable secondary glaucoma implies a severe and difficult-to-manage form of glaucoma. Various conditions can lead to secondary glaucoma, including uveitis, trauma, and certain types of eye surgeries.

## **Why the Correct Answer is Right**
The correct answer, **C.**, corresponds to a condition known to cause severe and challenging glaucoma. In this context, **C. Steroid-induced glaucoma** and other conditions listed could potentially cause glaucoma. However, steroid-induced glaucoma is a well-known cause of intractable secondary glaucoma due to its mechanism of action on the trabecular meshwork. Prolonged use of steroids can lead to increased resistance to aqueous outflow, resulting in elevated IOP.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because, although it could potentially represent a cause of glaucoma, without specifying the condition, it's hard to directly refute. Generally, most types of glaucoma have specific risk factors and mechanisms.
- **Option B:** Similarly, this option lacks specificity but could represent another form of glaucoma or ocular condition. Without specifics, it's challenging to directly address its incorrectness.
- **Option D:** This option is incorrect because, like A and B, without specifics, it's hard to assess directly. However, if we consider common causes of glaucoma, conditions like angle-closure glaucoma, open-angle glaucoma, or secondary glaucomas due to trauma or uveitis are well-defined entities.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that **steroid-induced glaucoma** can be particularly challenging to manage and might require surgical intervention. Patients on long-term steroid therapy, whether topical, inhaled, or systemic, should be monitored for signs of glaucoma. A classic clinical scenario involves patients with chronic uveitis who are on long-term steroid therapy.

## **Correct Answer:** .