Fasciculation differences between ALS and non-ALS patients: an ultrasound study

Abstract

Background Fasciculation is an important sign for the diagnosis of amyotrophic lateral sclerosis (ALS). Our study aimed to analyze the difference in fasciculation detected with muscle ultrasonography (MUS) between ALS patients and non-ALS patients with symptoms resembling ALS. Methods Eighty-eight ALS patients and fifty-four non-ALS (eight multifocal motor neuropathy, 32 chronic inflammatory demyelinating polyneuropathy/Charcot-Marie-Tooth, and 14 cervical spondylopathy or lumbar spondylopathy) patients were recruited. MUS was performed on 19 muscle groups in cervical, lumbosacral, bulbar, and thoracic regions for each patient. The intensity of fasciculation was divided into five grades based on firing frequency and number in the involved muscle groups. Results The overall detection rates were 72.8% in ALS and 18% in non-ALS patients. The fasciculation grades (median [IQR]) were 2 (0–3) in ALS and 0 (0–0) in non-ALS patients (P < 0.001). Fasciculations were observed in four regions for ALS patients and primarily distributed in proximal limbs. Fasciculations in non-ALS patients were primarily low-grade and mostly distributed in distal limbs. Discussion The fasciculation grade was higher in ALS than non-ALS patients. The distribution pattern of fasciculation was different between ALS and non-ALS patients. Conclusions The fasciculation grade and distribution pattern detected with MUS could help distinguish ALS from non-ALS patients.

A Case Report of an Incidental Ultrasound Finding in a Suspected Malignant Hyperthermia Patient

“…8,9 According to an intensity classification based on firing frequency and site number (Table ), the intensity of fasciculation in our patient before treatment with dantrolene was grade 4 (high grade). 10 A previous study suggested the intensity grading of fasciculation differs between ALS and non-ALS patients. 10 It is uncertain, however, whether grading fasciculation would provide diagnostic assistance in MH cases.…”

Abdominal Muscle Fasciculations and Amyotrophic Lateral Sclerosis Diagnosis in a Patient Unable to Perform Sit-Ups

“…In addition, MU is useful for differentiating between ALS (a positive likelihood ratio of 6.17) and non-ALS patients (a negative likelihood ratio of 0.04) [ 14 ]. The fasciculation grade, assessed by MU, was higher in ALS patients than in non-ALS patients, and the distribution pattern was more easily detected in the proximal limbs of ALS patients [ 15 ]. Several MU findings, such as the extent and frequency of fasciculations, the decrease in muscle thickness, and the increase in echogenicity, are useful for estimating ALS progression and prognosis [ 16 ].…”

Bedeutung der Muskelsonographie in der Detektion von Faszikulationen bei der ALS

“…der Zunge, 2: beidseitige Faszikulationen) bei einem Cut-Off-Wert von 3 eine Sensitivität von 86 % und eine Spezifität von 96 % sowie ähnliche Testgütekriterien in einer Validierungskohorte mit späterem ALS-Stadium [31]. Ähnliche Ergebnisse erbrachte die Anwendung eines 5-stufigen semiquantitativen Scores, in den für jeden analysierten Muskel sowohl Frequenz als auch örtliche Verteilung der Faszikulationen einging [32]. Es bleibt anzumerken, dass in keiner der Arbeiten nähere Angaben zu Untersuchungsdauer und -lokalisation der "nach klinischem Standard" durchgeführten Nadel-EMG-Untersuchung gemacht wurden, jedoch war die absolute Zahl der mit EMG untersuchten Muskeln angesichts der höheren Invasivität maximal gleich bzw.…”