Intraneural Perineurioma

**Semantic type:** Neoplastic Process

**Definition:** A WHO grade I perineurioma that arises within the endoneurium. It is characterized by the formation of pseudo-onion bulbs by the proliferating perineural cells.

**Synonyms:** - Intraneural Perineurioma (WHO Grade I) - Intraneural perineurioma