**Core Concept:**
Inverse Hypopyon refers to the presence of hypopyon, which is a collection of inflammatory cells (predominantly neutrophils) in the anterior chamber of the eye. The term "inverse" indicates that the hypopyon is seen at the base of the iris, opposite to the usual location in anterior uveitis. Hypopyon is usually associated with increased intraocular pressure and inflammation.

**Why the Correct Answer is Right:**
Correct Answer: **D. Uveitis**

Inverse Hypopyon is typically observed in situations where there is inflammation in the uvea, the middle layer of the eye consisting of the iris, ciliary body, and choroid. This type of inflammation, known as uveitis, is characterized by the presence of neutrophils in the anterior chamber. Inverse Hypopyon is seen when the intraocular inflammation primarily affects the posterior part of the uvea (e.g., iris or ciliary body), leading to a hypopyon located at the base of the iris, opposite to the typical anterior location in anterior uveitis.

**Why Each Wrong Option is Incorrect:**
A. **Anterior Uveitis (Iritis):**
Anterior uveitis involves inflammation in the anterior part of the uvea, predominantly affecting the iris, ciliary body, or both. Hypopyon is seen at the anterior chamber. Inverse Hypopyon would not be present in this context.

B. **Hypotony:**
Hypotony is a condition characterized by reduced intraocular pressure, which is not associated with Hypopyon or Inverse Hypopyon.

C. **Infectious keratitis:**
Infectious keratitis refers to inflammation of the cornea due to infection. Hypopyon is seen in the anterior chamber, but inverse hypopyon is not a relevant concept in this context.

D. **Uveitis:**
Uveitis is a broad term encompassing different types of uveitis, including anterior uveitis and posterior uveitis. Inverse Hypopyon is seen in posterior uveitis, where the inflammation primarily involves the iris or ciliary body, leading to the inverse location of the hypopyon at the base of the iris.

E. **Pseudohypopyon:**
Pseudohypopyon refers to a hypopyon that is not associated with inflammation, but rather, is caused by plasma proteins in the aqueous humor, such as in hyphema following trauma or surgery. Inverse Hypopyon is not relevant in this context.

**Clinical Pearls:**
1. Inverse Hypopyon is a characteristic feature of posterior uveitis, particularly when the inflammation primarily involves the iris or ciliary body. In this context, the hypopyon is located at the base of the iris, opposite to the typical anterior location in anterior uveitis.
2. Differentiating between anterior uveitis and posterior uveitis is essential to guide appropriate treatment and monitor disease progression. Knowledge of inverse hypopyon aids in distinguishing posterior uveitis from anterior uveitis, which may have different clinical presentations and management strategies.