What is not a feature of paralytic squint –
**Core Concept**
Paralytic squint, also known as paralytic strabismus, is a type of strabismus caused by weakness or paralysis of one or more extraocular muscles. This condition leads to misalignment of the eyes, resulting in double vision or loss of binocular vision.
**Why the Correct Answer is Right**
The key features of paralytic squint include:
- Diplopia (double vision) due to lack of coordination between the two eyes.
- Incomitance, where the angle of deviation varies between different directions of gaze.
- Limitation of movement in the affected muscle, leading to restrictive strabismus.
- Presence of a compensatory head posture to minimize diplopia.
**Why Each Wrong Option is Incorrect**
**Option A:** Heterophoria, a latent deviation that appears only when the patient is asked to maintain a specific posture, is a feature of paralytic squint.
**Option B:** Incomitance is indeed a characteristic of paralytic squint, as the angle of deviation varies between different directions of gaze.
**Option C:** Limitation of movement in the affected muscle is a key feature of paralytic squint, leading to restrictive strabismus.
**Clinical Pearl / High-Yield Fact**
A classic clinical finding in paralytic squint is the presence of a compensatory head posture, which the patient adopts to minimize diplopia. This can be a useful clue in differentiating paralytic squint from other types of strabismus.
**Correct Answer: D.**