An evaluation of the kinetics of skin lesion evolution in psoriasis was made by quantitative histogeometric measurements of tissue changes occurring in barely perceptible punctate early papules of the disease and by comparing these to changes in plaque-type older lesions. Marked thickening of the granular layer in the epidermis paracentrally in early punctate lesions was found to occur consistently. In plaque lesions similar thickening of the granular layer was found at the margins, immediately peripheral to the rim of maximal epidermal thickness. The granular layer in central areas of plaques was variably diminished or accentuated in thickness. The kinetics of lesion evolution and resolution may provide some new aspects on the pathogenesis of psoriasis beyond those gained from tissue changes conventionally held as characteristic of this disease.
Soltani K, Van Scott EJ. Patterns and Sequence of Tissue Changes in Incipient and Evolving Lesions of Psoriasis. Arch Dermatol. 1972;106(4):484-490. doi:10.1001/archderm.1972.01620130016005