Utility Of Fasciculation Score And Diaphragmatic Ultrasound In Amyotrophic Lateral Sclerosis

Part 1.Diaphragm ultrasound in the diagnosis of respiratory dysfunction in patients with amyotrophic lateral sclerosisObjective:In this study,we aimed to select the best diaphragm ultrasonography(DUS)parameter as an alternative index for the diagnosis of lung function impairment in amyotrophic lateral sclerosis(ALS).Methods:29 patients with ALS and 15 healthy subjects were enrolled in the study.DUS,lung function tests,phrenic nerve conduction study and arterial blood gas analysis were performed.Results:Patients with respiratory dysfunction have significant lower level of ΔTmax than those without(P = 0.039).Significant correlations(P < 0.05)were found between forced vital capacity(FVC)and Tdi-ins(r = 0.665,P < 0.0001)and ΔTmax(r =-0.748,P < 0.0001)andΔins-exp(r = 0.627,P < 0.0001)and ΔTdi(r = 0.485,P < 0.0001).Receiver Operating Curves analysis demonstrated that ΔTmax(AUC = 0.76,P = 0.044)had a better overall accuracy for detection of respiratory dysfunction compared with Tdi-ins(AUC = 0.27,P =0.067),Δins-exp(AUC = 0.312,P = 0.139),and ΔTdi(AUC = 0.38,P = 0.359).Conclusion:ΔTmax is the most valuable DUS index in the diagnosis of diaphragmatic dysfunction.Significance: DUS can provide functional and structural information of diaphragm and help to diagnose diaphragmatic dysfunction in ALS.Part 2.Fasciculation score: a sensitive biomarker in amyotrophic lateral sclerosisObjective:The aim of our study was to elucidate the characteristic of fasciculation distributions in amyotrophic lateral sclerosis(ALS)using a fasciculation score(FS)of muscle ultrasound(MUS),and to compare the diagnostic values of three MUS fasciculation parameters in patients.Methods:35 ALS patients,16 ALS mimics and 10 healthy subjects were involved.MUS of unilateral10 muscles in each patient and needle electromyography(EMG)of total 204 muscles were performed to detect fasciculations and spontaneous activity respectively in ALS.Control groups underwent only MUS.Fasciculation was graded semi-quantitatively with FS.Results:350 muscles in ALS and 260 in controls were examined.The fasciculation detection rates,total FS,the number of muscles with fasciculation and total number of fasciculations in ALS were all significantly higher than those of controls(P < 0.001).ALS patients exhibited multifocal continuous pattern of fasciculation in limbs whereas there were few fasciculations in controls.Compared with other parameters,total FS had the largest AUC(AUC = 0.899,P < 0.001)in ALS diagnosis.The detection rates of LMN acute lesions by MUS(70.6%)and EMG(72.1%)were nearly the same and positive correlation between the FS and spontaneous activity grades(P < 0.001,r = 0.359)was proved.Conclusions:ALS patients exhibited multifocal continuous pattern of fasciculation in limbs.FS showed high sensitivity and specificity in differentiating ALS from non-ALS patients and the optimal cut-off value was determined as 4.The combination of MUS and EMG can provide additional information about specific muscles.