The ñ Sign: A Visual Clue for the Histopathologic Diagnosis of Psoriasis.

This qualitative study describes a visual clue for the diagnosis of psoriasis, in which the sum of the fragmentation and separation of the laminar parakeratotic stratum corneum and hyperplasia with regular elongation of the rete ridges resembles the letter ñ on histopathologic biopsy specimens.

[Histological characteristics of head and neck paragangliomas].

Paragangliomas arise from the extra-adrenal paraganglion system. Histologically, paragangliomas are usually easy to diagnose, with well-defined characteristics. These lesions are clearly delimited and highly vascular and are composed of cell balls (Zellballen) separated by thin fibrous septa.