ObjectivesIntraneural perineurioma is a rare, benign neoplasm of peripheral nerve. The histopathological features are well defined.DesignWe describe 5 cases of histologically confirmed perineuriomas and 14 cases diagnosed on clinical and radiological characteristics to highlight the features of this rare entity.MethodsWe identified cases from the imaging and histopathology database and conducted a retrospective case note review.ResultsThe subjects include 7 men and 12 women, with mean (standard deviation) age of 17.64 (13) years at onset of symptoms. 14 of the 15 lower limb cases were located in the sciatic nerve or its divisions. 1 each was identified in ulnar, median and radial nerves and 1 case was in a facial nerve. The MRI features were homogenous between the groups. The nerves biopsied included 1 tibial, 1 ulnar, 1 radial, 1 facial and 1 sciatic all showing classic pathology findings. 2 patients, interestingly, had coincidental intracranial meningioma, given the recent discovery of a potential shared pathogenesis (mutations in TRAF7) with intracranial meningiomas. 2 patients had ‘skip lesions’ within the same nerve and 3 patients had foraminal and extraforaminal involvement of lumbosacral nerve roots.ConclusionsOur unit now favours the clinicoradiological features for diagnosing perineuriomas rather than performing a biopsy on all patients. Also, the potential shared pathogenesis with meningiomas raises the clinical issue of screening in patients with perineuriomas but more clinical evidence is required.
Intraneural perineurioma
