Ultrasonography of peripheral nerve tumours: a case series

Abstract

Background. Peripheral nerve tumours (PNTs) are rare, but important cause of peripheral nerve dysfunction. The aim of the study was to present a series of consecutive patients with peripheral nerve tumors (PNT) evaluated in authors’ ultrasonography (US) practice.

Patients and methods. I retrospectively reviewed the electronic medical records of patients with PNTs examined at our US laboratory from February 2013 to May 2020. In all patients I collected data on gender, age, clinical features, PNT location, electrodiagnostic (EDx) and US findings.

Results. I identified PNTs in 15 patients. Four of them (3 with confirmed neurofibromatosis) had multiple PNTs. Half of patients (53%) presented with features of peripheral nerve damage, and others with palpable mass or pain. The most often involved nerve was ulnar (36%). PNT cross sectional areas varied from 24 mm² to 1250 mm² (median, 61 mm²). Based in 5 patients on histological and in remaining patients on US features I diagnosed schwannoma in 40%, neurofibroma in 27%, and perineurioma in 27% patients.

Conclusions. PNTs are rare, but important cause of peripheral nerve dysfunction. Usually they present with neurological symptoms, palpable mass or pain. In patients with multiple PNTs neurofibromatosis should be considered. In children presenting with unexplained focal nerve lesion perineurioma is a possibility. Ulnar nerve PNTs at the elbow are common and sometimes difficult to differentiate from ulnar neuropathy at the elbow. In contrast to other focal neuropathies, particularly nerves with schwannomas, in spite of their large size, often demonstrate well preserved nerve function.