Managing uncommon and unexpected findings during neuromuscular ultrasound

Abstract

One barrier to widespread adoption of neuromuscular ultrasound by clinical neurophysiologists is concern over how to identify and manage non-neuromuscular findings. This review addresses this concern by describing the sonographic appearance of a variety of commonly observed pathologies and anatomic variants in dermal, subcutaneous, bony, glandular, lymphatic, vascular, and other superficial tissues. Additionally, it outlines techniques to ensure proper clinical and ultrasound evaluation of unexpected or uncommon findings. Finally, it highlights strategies to manage unexpected findings, including how to best communicate findings to patients and referring clinicians to avoid unnecessary testing and ensure appropriate follow-up. Ultrasound extends the ability of the neuromuscular sonographer-clinician to contribute to patient care.

Extradigital Glomus Tumor of the Forearm Identified During Neuromuscular Ultrasound: A Case Report

“…On a sonogram, a ganglion cyst may resemble glomus tumor and appears as a hypoechoic or anechoic noncompressible swelling with well-defined margins, but it often demonstrates internal septations and acoustic enhancement. [17][18][19] In contrast to simple cysts, abscesses typically appear as anechoic or hypoechoic compressible swelling with thick poorly defined wall and internal septation. 17 Neurofibroma and schwannoma, the most common nerve sheath tumors, may mimic glomus tumor and manifest as a painful palpable lump.…”

“…[17][18][19] In contrast to simple cysts, abscesses typically appear as anechoic or hypoechoic compressible swelling with thick poorly defined wall and internal septation. 17 Neurofibroma and schwannoma, the most common nerve sheath tumors, may mimic glomus tumor and manifest as a painful palpable lump. On sonography, they commonly appear hypoechoic and show internal blood flow, but they are easily distinguished from glomus tumor by their continuity with a nerve.…”

“…The sonographic appearance of lipomas can be highly variable, but it commonly appears as a well-defined isoechoic or hyperechoic avascular elliptical or lobulated subcutaneous mass with no acoustic shadow. 17 Doppler flow may be indicative of liposarcoma. Similar to lipoma, ganglion cysts are usually painless but may occasionally cause mild pain.…”

Developing a framework for neuromuscular ultrasound training and accreditation

“…16 It is likely that a clinician performing NMUS will eventually identify pathology within the scanned field that may be incidental or relevant to the presenting symptoms but not within nerve and muscle. 17…”

“…One consideration not raised by the authors was the implication of limiting training and, hence, competency assessment to nerve and muscle anatomy and pathology 16 . It is likely that a clinician performing NMUS will eventually identify pathology within the scanned field that may be incidental or relevant to the presenting symptoms but not within nerve and muscle 17 . Without specific training in soft tissue and musculoskeletal anatomy and disease the clinician may miss or misdiagnose the abnormality with potentially adverse consequences.…”