## **Core Concept**
Lattice corneal dystrophy is a rare, autosomal dominant disorder characterized by the accumulation of abnormal protein deposits in the cornea, leading to corneal opacity and vision impairment. The condition primarily affects the cornea's stroma. The deposits are primarily composed of amyloid.

## **Why the Correct Answer is Right**
The correct answer, amyloid, is right because lattice corneal dystrophy is pathologically characterized by the deposition of amyloid in the corneal stroma. This amyloid deposition leads to the formation of lattice-like lines or streaks within the cornea, which is a hallmark of the disease. The amyloid deposits are produced due to mutations in the TGFBI gene, which encodes for transforming growth factor beta-induced protein (TGFBIp) or keratoepithelin. These mutations lead to the production of abnormal keratoepithelin, which aggregates and forms amyloid fibrils.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because while hyaline can form deposits in various tissues, it is not specifically associated with lattice corneal dystrophy.
- **Option B:** Glycogen deposits are not characteristic of lattice corneal dystrophy; they are more commonly associated with conditions like von Gierke's disease.
- **Option C:** Lipid deposits are not the primary type of deposit seen in lattice corneal dystrophy; they are more commonly associated with conditions like lipid keratopathy.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl for lattice corneal dystrophy is that it often presents with recurrent corneal erosions and visual disturbances. A classic feature is the presence of lattice-like amyloid deposits in the corneal stroma, which can be visualized with a slit lamp. Early diagnosis and treatment, such as corneal transplantation, are crucial to prevent vision loss.

## **Correct Answer: D. Amyloid**