Background/Purpose: Our earlier studies have demonstrated that sacral magne
tic stimulation (MS) in the canine model, in healthy volunteers and in cons
tipated subjects brought about a rise in rectal pressure and a decline in r
ectal neck (anal canal) pressure as well as rectal evacuation. Based on the
se results, we studied the effect of sacral MS on defecation in patients wi
th paradoxical puborectalis syndrome (PPS). Methods: Eleven subjects (8 wom
en, 3 men; age 36-53 years) with PPS were enrolled in the study. The magnet
ic coil was placed on the back with its center located between L4 and L5. S
timulation parameters were set at 70% of maximum intensity, 40 Hz frequency
and 2 s burst length with 2 s off. During MS, the rectal neck and gastric
(intra-abdominal) pressures were measured. The procedure was performed in t
he empty and the full rectum using the balloon expulsion test in the latter
. Results: MS of the empty and balloon-filled rectum brought about a rise i
n the rectal pressure (p < 0.001), decline in rectal neck pressure (p < 0.0
01) and no significant change in intragastric pressure (p > 0.05). The ball
oon was expelled by all patients. Conclusions: Sacral MS succeeded in expel
ling the water-filled rectal balloon. The method is simple, easy, noninvasi
ve, nonradiologic and can be performed on an outpatient basis in the treatm
ent of PPS. Copyright (C) 2000 S. Karger AG, Basel.