Eye examination of a person reveals near reflex to be present but light reflex is lost. What is this condition known as?
## **Core Concept**
The question tests the understanding of pupillary reflexes, specifically the near reflex and light reflex, which are crucial in ophthalmology and neurology. The near reflex involves constriction of the pupil when focusing on a near object, and the light reflex involves constriction of the pupil in response to light. These reflexes are mediated by different pathways.
## **Why the Correct Answer is Right**
The condition described, where the near reflex is present but the light reflex is lost, is known as **Argyll Robertson pupil**. This condition is characterized by bilateral small pupils that constrict when the patient focuses on a near object (accommodative response) but do not react or react poorly to light. This dissociation between the light and near reflexes is a classic sign of neurosyphilis, particularly in the context of tabes dorsalis or general paresis.
## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because it is not specified, but based on the context, it's likely not related to the specific condition described.
- **Option B:** Similarly, without specification, it's hard to directly refute, but it's not the correct term for the condition described.
- **Option C:** This could potentially be a distractor related to pupillary abnormalities, but it does not accurately describe the specific condition of preserved near reflex with loss of light reflex.
## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that Argyll Robertson pupils are often associated with neurosyphilis. The presence of this condition should prompt investigation for syphilis, particularly in the appropriate clinical context. Remember, the mnemonic could be "light out, near in" for Argyll Robertson pupils.
## **Correct Answer:** D. Argyll Robertson pupil.