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Published on: August 28, 2020
The artificial somato-autonomic reflex arch does not improve lower urinary tract function in patients with spinal
Mikkel Mylius Rasmussen1, Yazan F Rawashdeh2, Dorte Clemmensen3
1Pelvic Floor Unit, Department of Surgery, Aarhus University Hospital, Aarhus, Denmark; Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark.
Purpose:
The artificial somato-autonomic reflex arch (Xiao procedure) was proposed as treatment for neurogenic bladder dysfunction. We investigated the effects of the procedure on lower urinary tract function.
Materials And Methods:
Seven and 3 patients with a median age of 46 years (range 19 to 64) had AIS A and B spinal cord injury, respectively. In these patients an anastomosis was created between the ventral (motor) part of L5 and the ventral part of the S2 root. Urodynamics were performed and a standard questionnaire was completed at baseline and 18 months postoperatively.
Results:
Artificial reflex arch stimulation did not initiate voiding or increase bladder pressure. Maximum bladder capacity did not change significantly from baseline to followup (median 427.5 ml, range 168 to 581 vs 498.5, range 271 to 580, p = 0.09). Likewise, bladder compliance did not significantly differ at baseline and followup (median 16.9 ml/cm H2O, range 15.0 to 65.0 vs 25.1, range 17.5 to 50.0, p = 0.95). No difference was found in awareness of bladder emptying, incontinence episodes, bladder emptying method or medication use for neurogenic bladder dysfunction. The only statistically significant change was a decreased incidence of leakage at followup on urodynamics (p = 0.03). Postoperatively decreased genital sensation and erectile dysfunction developed in 1 patient and another experienced a minor cerebrovascular accident with no long-term complications.
Conclusions:
In contrast to earlier findings, creation of an artificial somato-autonomic reflex arch in patients with spinal cord injury had no clinically relevant effect on lower urinary tract function.
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