There is a very distinctive and characteristic wavy or corrugated, refractile keratinization at the luminal surface, often as sociated with parakeratotic
epithelial cells (figure 2).
The affected keratinocytes fail to undergo normal keratinisation and are pushed upwards to form a compact parakeratotic
layer beneath the previously normal orthokeratotic stratum corneum.
On microscopic examination, multifocal areas of full-thickness epidermal proliferation with a parakeratotic
hyperkeratosis were observed, interspersed with areas of intense epidermal necrosis in the skin of the feet and periocular region (Fig 3).
Histopathological studies showed inhibition in cellular infiltration and reduction of synovial hyperplasia and synovitis, whereas in the second test, histopathological and ultrastructural studies showed that topical application of FAM induced orthokeratosis with the presence of keratohyalin granules in the previously parakeratotic adult mouse tail, and without effects on epidermal thickness.
Ten sequential scales were examined for the presence of a granular layer induced in the previously parakeratotic skin areas.
Microscopy of skin sections containing epidermis showed compact keratinization, parakeratotic
foci, and irregular hyperplasia with a pseudoepitheliomatous area.
In contrast to common dyskeratotic cells, which have a dense eosinophilic cytoplasm and mature to parakeratotic
cells, pagetoid dyskeratotic cells are pale, show intercellular prickles with the adjacent keratinocytes, and mature to orthokeratotic keratinization.
It's also important to remove excessive material from the stratum corneum and the parakeratotic
layer to expose the skin, let it dry, and allow the ototopical agent to be absorbed.
Histology of the lesions is characterized by hyperkeratosis and central parakeratotic