E. Eisman et J. Tries, A NEW PROBE FOR MEASURING ELECTROMYOGRAPHIC ACTIVITY FROM MULTIPLE SITES IN THE ANAL-CANAL, Diseases of the colon & rectum, 36(10), 1993, pp. 946-952
A new multiple electrode probe (MEP) designed to measure surface elect
romyographic activity from the subcutaneous and deep portions of the e
xternal anal sphincter is described. Using the MEP, electromyographic
activity was sampled in an asymptomatic subject and in three incontine
nt patients. Comparisons of electromyographic data between and within
subjects, and across sessions, indicate that the MEP discriminates mus
cle activity from different sites along the anal canal. The recording
method described is capable of identifying patterns of muscle recruitm
ent which have not been reported before using surface electromyography
. After a defecation maneuver, the distal and proximal portions of ext
ernal and sphincter were observed to contract in what would seem to be
a closing reflex. Moreover, the absence of this pattern may indicate
abnormality. Accordingly, the MEP promises to be useful in the diagnos
is, evaluation, and treatment of fecal and urinary incontinence and, p
articularly, in the biofeedback treatment of these and related disorde
rs.