Blepharitis: This is an inflammation of the eyelids that can cause dry, scaly, itchy spots. It's a common condition that can be due to a variety of factors including poor eyelid hygiene, makeup, or certain skin conditions.

Eczema (Atopic Dermatitis): This is a chronic skin condition characterized by itchy, inflamed skin, which can affect the eyelids and cause dry, scaly patches.
Seborrheic Dermatitis: A skin condition that can cause scaly patches, red skin, and stubborn dandruff, often affecting oily areas of the body like the face, including the eyelids.
Contact Dermatitis: An allergic reaction or irritation to substances like makeup, makeup remover, or certain chemicals that come into contact with the eyelids, leading to itchy, scaly spots.
Psoriasis: An autoimmune condition that speeds up the life cycle of skin cells, causing cells to build up rapidly on the surface of the skin, leading to scaly patches. Though less common on the eyelids, it can occur.

Basal Cell Carcinoma: Although rare on the eyelid, this type of skin cancer can present as a new, growing lesion that might initially appear as a small, scaly spot. Early detection is crucial.
Squamous Cell Carcinoma: Another form of skin cancer that can appear on the eyelids, often as a firm, red nodule or a flat sore with a scaly crust.

Keratoacanthoma: A low-grade, or sometimes considered benign, tumor of the skin that can resemble squamous cell carcinoma but typically has a more rapid growth phase followed by stabilization and sometimes spontaneous resolution.
Discoid Lupus Erythematosus: A chronic skin condition of sores with inflammation and scarring favoring the face, ears, and scalp but can rarely affect the eyelids, causing scaly, itchy lesions.