Muscle ultrasound aids diagnosis in amyotrophic lateral sclerosis

Andrew Hannaford; Nathan Pavey; Parvathi Menon; Mehdi A J van den Bos; Matthew C Kiernan; Neil Simon; Steve Vucic

doi:10.1016/j.clinph.2024.11.008

Muscle ultrasound aids diagnosis in amyotrophic lateral sclerosis

Clin Neurophysiol. 2024 Nov 22:S1388-2457(24)00331-6. doi: 10.1016/j.clinph.2024.11.008. Online ahead of print.

Authors

Andrew Hannaford¹, Nathan Pavey², Parvathi Menon², Mehdi A J van den Bos², Matthew C Kiernan³, Neil Simon⁴, Steve Vucic²

Affiliations

¹ Brain and Nerve Research Centre, Concord Clinical School, University of Sydney, Concord Hospital, Sydney, NSW, Australia. Electronic address: andrew.hannaford@sydney.edu.au.
² Brain and Nerve Research Centre, Concord Clinical School, University of Sydney, Concord Hospital, Sydney, NSW, Australia.
³ Neuroscience Research Australia, Sydney, NSW, Australia.
⁴ Faculty of Medicine and Health Sciences, Macquarie University, NSW, Australia.

PMID: 39581840
DOI: 10.1016/j.clinph.2024.11.008

Abstract

Objective: There is a need for improved diagnostic tools in Amyotrophic Lateral Sclerosis (ALS). Our objective was to assess muscle ultrasound as a diagnostic tool in patients with ALS and determine a simplified screening protocol to aid implementation in clinical practice.

Methods: Ultrasound of bulbar and limb muscles was prospectively performed on all patients referred to a single centre with suspected ALS. Clinical measures of disease severity and upper motor neuron impairment were also recorded. Receiver operating characteristic (ROC) curves were calculated to assess the diagnostic utility of muscle ultrasound.

Results: 94 patients initially suspected of ALS were recruited to this observational cohort study. Forty-four were subsequently diagnosed as ALS and 50 as disease mimics. ALS patients demonstrated a higher frequency and more generalised distribution of fasciculations compared to mimics. A simplified 5 muscle screening protocol exhibited an AUC of 0.94 (95 %CI 0.89-0.99) in discriminating ALS from mimics. The presence of ≥ 3 fasciculating muscles detected using this screening protocol was 89 % sensitive and 88 % specific for the diagnosis of ALS.

Conclusions: Muscle ultrasound, screening as few as 5 muscles, has diagnostic utility in ALS.

Significance: Muscle ultrasound enhances clinical diagnosis in ALS.

Keywords: Amyotrophic Lateral Sclerosis; Diagnosis; Fasciculations; Muscle ultrasound.