Which is Less nephrotoxic?
**Core Concept**
The nephrotoxicity of various contrast media used in radiology is a critical consideration for patients with pre-existing kidney disease. The mechanism of nephrotoxicity involves the generation of reactive oxygen species and the deposition of iodine in renal tubules.
**Why the Correct Answer is Right**
The correct answer is **B. Iodixanol**. Iodixanol is a non-ionic, iso-osmolar contrast medium that is less likely to cause nephrotoxicity due to its non-ionic nature and similar osmolality to blood. This reduces the osmotic stress on renal tubules, making it a safer choice for patients with kidney disease. In contrast, ionic contrast media like **Option A: Iopamidol** and **Option C: Iohexol** can cause more significant nephrotoxicity due to their ionic nature and higher osmolality.
**Why Each Wrong Option is Incorrect**
* **Option A:** Iopamidol is an ionic, non-iso-osmolar contrast medium that can cause nephrotoxicity due to its ionic nature and higher osmolality.
* **Option C:** Iohexol is an ionic, non-iso-osmolar contrast medium that can cause nephrotoxicity due to its ionic nature and higher osmolality.
**Clinical Pearl / High-Yield Fact**
When choosing a contrast medium for patients with kidney disease, it's essential to select an iso-osmolar, non-ionic agent like Iodixanol to minimize the risk of nephrotoxicity.
**Correct Answer: B. Iodixanol**