**Question:** Most common late post-op complication of cataract Surgery is

A. Endophthalmitis
B. Hypotony
C. IOL tilt or decentration
D. Cataract recurrence

**Core Concept:**
Cataract surgery is a common surgical procedure performed to improve vision in patients with cataracts. Post-operative complications can occur due to various reasons, including infection, intraocular pressure issues, and IOL positioning issues. Understanding these complications helps in providing appropriate management and patient care.

**Why the Correct Answer is Right:**
The most common late post-op complication of cataract surgery is **Cataract recurrence** (Option D). Cataract recurrence refers to the regrowth of the cataractous lens substance after surgery, leading to a decrease in visual acuity. Although uncommon, this can occur due to various reasons, such as inadequate removal of the cataractous lens substance, incomplete removal of the cortex (the outer layer of the lens), or the presence of a small residual cataractous nucleus.

**Why Each Wrong Option is Incorrect:**

A. **Endophthalmitis (Option A)** is an infection within the eye. While endophthalmitis can occur as a late complication of cataract surgery, it is less common compared to cataract recurrence.

B. **Hypotony (Option B)** is characterized by low intraocular pressure (IOP), which can lead to ocular complications. While hypotony may be seen as a late complication, it is less common than cataract recurrence.

C. **IOL tilt or decentration (Option C)** refers to the misalignment or displacement of the intraocular lens (IOL) from its intended position. Although IOL tilt or decentration can occur as a complication, it is less common than cataract recurrence.

**Clinical Pearl:**
In clinical practice, it is essential to closely monitor patients for signs of cataract recurrence after cataract surgery. If detected early, cataract recurrence can be managed effectively by performing a repeat lens extraction procedure.