All of the following are employed to evaluate a case of heterophoria except
**Core Concept**
Heterophoria is a type of eye movement disorder characterized by an involuntary deviation of the eyes when fixation is broken, but alignment is maintained when the eyes are fixating on a target. It is often assessed using various clinical tests to determine the underlying cause and treatment options.
**Why the Correct Answer is Right**
To evaluate a case of heterophoria, clinicians use a combination of clinical tests to assess the patient's eye movements, including cover-uncover tests, near point of convergence, and prism cover test. These tests help to determine the type and magnitude of heterophoria, which is essential for developing an effective treatment plan.
**Why Each Wrong Option is Incorrect**
**Option A:** The cover-uncover test is a common method used to evaluate heterophoria, so this option is incorrect.
**Option B:** Near point of convergence is a test used to assess convergence insufficiency, which can be a type of heterophoria, making this option incorrect.
**Option C:** Prism cover test is a specific type of cover-uncover test used to measure heterophoria, so this option is incorrect.
**Clinical Pearl / High-Yield Fact**
It's essential to note that heterophoria can be classified into three types: esophoria (inward deviation), exophoria (outward deviation), and cyclotropia (rotational deviation). Understanding the type and magnitude of heterophoria is crucial for developing an effective treatment plan.
**Correct Answer: D.**