Annular granular pattern dermoscopy

What is an annular granular pattern?

An annular granular pattern consists of grey or brown dots (granular) around follicular openings (annular) and is regarded as a characteristic of lentigo maligna. In descriptive terminology, it is known as 'grey dots arranged around follicular openings' [1].

What does an annular granular pattern look like through the dermatoscope?

Through the dermatoscope, an annular granular pattern is seen as:

• Dots and structureless areas arranged around follicle openings (and involving adnexal openings)
• Gray dots and circles on the face.

Annular granular pattern seen in dermoscopy of lichen planus-like keratosis

Annular granular pattern and rhomboids seen in dermoscopy of lentigo maligna

Annular granular pattern and rhomboids seen in dermoscopy of lentigo maligna melanoma

In which lesions is an annular granular pattern seen in through the dermatoscope?

Through the dermatoscope, an annular granular pattern may be seen in the following lesions:

• Lentigo maligna
• Pigmented actinic keratosis
• Lichen planus-like keratosis.

In lichen planus-like keratosis, grey dots around the follicular openings tend to be coarse, regular and widespread, whereas in lentigo maligna they are much finer and focal.

Annular granular pattern seen in dermoscopy of lichen planus-like keratosis

Annular granular pattern seen in dermoscopy of lichen planus-like keratosis

Annular granular pattern seen in dermoscopy of lichen planus-like keratosis

Annular granular pattern seen in pigmented actinic keratosis

Annular granular pattern seen in lentigo maligna demoscopy

Annular granular pattern seen in dermoscopy of lentigo maligna

What is the histological explanation of an annular granular pattern?

Histologically, slate grey dots are due to melanin in melanophages.