Objective: Motor unit potential (MUP) morphology can bequantified using parame ters describing electrophysiological size and shape (complexity). Traditionally, MUP complexity has been estimated using parameters number...Objective: Motor unit potential (MUP) morphology can bequantified using parame ters describing electrophysiological size and shape (complexity). Traditionally, MUP complexity has been estimated using parameters number of phases and turns. Recently, ‘irregularity coefficient’(IR), measuring the length of the MUP curv e normalized with its amplitude, has been introduced. The aim of this study was to evaluate IR in the external anal sphincter muscle. Methods: Sensitivity was e xamined in 61 patients with chronic cauda equina lesions, and specificity in 75 controls using a standard concentric EMG needle and EMG system with multi-MUP a nalysis. Results: When evaluated separately the sensitivity of IR was 16%lower, and specificity 5%higher compared to number of turns, with both differences de creasing to only 2 and 1%, respectively, when each of these parameters was adde d to MUP area and duration.Conclusions: Our present results suggest that IR prov ides a similar diagnostic usefulness, but a more appropriate description of MUP complexity compared to traditional MUP parameters.Significance: IR seems to be s uitable to complement one of MUP parameters measuring electrophysiological MUP s ize in the future quantitative EMG.展开更多
For the external anal sphincter muscle, both normative values and an optimal s et of motor unit potential (MUP) parameters have been defined. However, criteria for the diagnosis of neuropathic conditions have not yet ...For the external anal sphincter muscle, both normative values and an optimal s et of motor unit potential (MUP) parameters have been defined. However, criteria for the diagnosis of neuropathic conditions have not yet been validated. Theref ore, in this study, sensitivity was examined in 86 patients with cauda equina le sions (227 muscles), and specificity in 77 controls (119 muscles), using multi MUP analysis. Six previously defined diagnostic criteria (mean values and outlie rs for MUP area, duration, and number of turns) were used. An increase in the nu mber of diagnostic criteria required for muscle abnormality (two and three inste ad of one), and the application of more stringent normative limits resulted in a progressive increase in specificity from 74%to 99%(controls), and a decrease in sensitivity from 70%to 21%(patients). The data suggest that no single cut off diagnostic criterion has both satisfactory sensitivity and specificity. Intr oduction of the diagnostic categories of “possible,”“probable,”and “definit e”neuropathic abnormalities into quantitative electromyographic analysis is pro posed.展开更多
文摘Objective: Motor unit potential (MUP) morphology can bequantified using parame ters describing electrophysiological size and shape (complexity). Traditionally, MUP complexity has been estimated using parameters number of phases and turns. Recently, ‘irregularity coefficient’(IR), measuring the length of the MUP curv e normalized with its amplitude, has been introduced. The aim of this study was to evaluate IR in the external anal sphincter muscle. Methods: Sensitivity was e xamined in 61 patients with chronic cauda equina lesions, and specificity in 75 controls using a standard concentric EMG needle and EMG system with multi-MUP a nalysis. Results: When evaluated separately the sensitivity of IR was 16%lower, and specificity 5%higher compared to number of turns, with both differences de creasing to only 2 and 1%, respectively, when each of these parameters was adde d to MUP area and duration.Conclusions: Our present results suggest that IR prov ides a similar diagnostic usefulness, but a more appropriate description of MUP complexity compared to traditional MUP parameters.Significance: IR seems to be s uitable to complement one of MUP parameters measuring electrophysiological MUP s ize in the future quantitative EMG.
文摘For the external anal sphincter muscle, both normative values and an optimal s et of motor unit potential (MUP) parameters have been defined. However, criteria for the diagnosis of neuropathic conditions have not yet been validated. Theref ore, in this study, sensitivity was examined in 86 patients with cauda equina le sions (227 muscles), and specificity in 77 controls (119 muscles), using multi MUP analysis. Six previously defined diagnostic criteria (mean values and outlie rs for MUP area, duration, and number of turns) were used. An increase in the nu mber of diagnostic criteria required for muscle abnormality (two and three inste ad of one), and the application of more stringent normative limits resulted in a progressive increase in specificity from 74%to 99%(controls), and a decrease in sensitivity from 70%to 21%(patients). The data suggest that no single cut off diagnostic criterion has both satisfactory sensitivity and specificity. Intr oduction of the diagnostic categories of “possible,”“probable,”and “definit e”neuropathic abnormalities into quantitative electromyographic analysis is pro posed.
