‘Teichopsia’ is seen in
**Core Concept**
Teichopsia is a rare visual phenomenon characterized by the perception of seeing cobblestones, pebbles, or other small objects on the retina. This condition is often associated with changes in the retina, particularly in the macula, which is responsible for central vision.
**Why the Correct Answer is Right**
Teichopsia is typically seen in conditions that affect the macula, such as age-related macular degeneration (AMD), diabetic retinopathy, or retinal detachment. The macula contains specialized photoreceptors that are sensitive to light and color, and damage to this area can cause distorted or abnormal visual perceptions. The perception of cobblestones or pebbles is thought to be due to the abnormal wiring of the retina, which sends incorrect signals to the brain.
**Why Each Wrong Option is Incorrect**
* **Option A:** While migraines can cause a range of visual disturbances, including auras and blind spots, they are not typically associated with teichopsia.
* **Option B:** Retinal vein occlusion can cause sudden vision loss, but it is not typically characterized by teichopsia.
* **Option C:** Macular edema can cause distorted vision, but it is not typically associated with the specific phenomenon of teichopsia.
**Clinical Pearl / High-Yield Fact**
Teichopsia is a classic example of a "Charles Bonnet syndrome," which refers to complex visual hallucinations caused by changes in the retina or optic nerve. This condition highlights the importance of a thorough ophthalmologic examination in patients with visual disturbances.
**Correct Answer: D. Macular disease. Macular disease.**