The Mode of Action of Adjustable Transobturator Male System (ATOMS): Intraoperative Urethral Pressure Measurements

Abstract

(1) Background: The Adjustable Transobturator Male System (ATOMS) device is increasingly used to treat post-prostatectomy incontinence as it enhances residual urinary sphincteric function and allows continence recovery or improvement by dorsal compression of the bulbar urethra through a fixed transobturator mesh passage. The mode of action and the profile of the patients with best results are not totally understood. (2) Methods: Intraoperative urethral pressure measurements at different filling levels of the ATOMS device show increased urethral resistance and enhanced residual sphincteric activity. We evaluated whether the pattern of urethral pressure change secondary to serial progressive intraoperative filling of the cushion can predict postoperative results after ATOMS placement. (3) Results: The regression analysis showed a significant direct relationship between cushion volume and intraurethral pressure (p = 0.000). The median intraurethral pressure at atmospheric pressure was 51 ± 22.7 cm H2O, and at atmospheric pressure plus 4 mL was 80 ± 23.1 cm H2O). Cluster analyses defined a group of patients (n = 6) formed by patients with a distensible urethra and 100% continence after adjustment in contrast to another group (n = 3) with rigid urethras and 33% continence after adjustment. (4) Conclusions: As a part of its continence mechanism, the ATOMS device leads to continence by increasing intraurethral pressure owing to the stretching effect on the urethral wall caused by cushion filling that increases urethral resistance.

Update on Adjustable Trans-Obturator Male System (ATOMS) for Male Incontinence after Prostate Cancer Surgery

“…ATOMS increases residual sphincteric function to achieve continence by increasing intraurethral pressure, secondary to the stretching effect on the urethral wall caused by cushion filling, which increases urethral resistance [ 23 ]. The tension is increased proportionally to the urethral stretching effect produced by the fibrotic capsule in the periphery of the ATOMS cushion.…”

“…The urethral stretching effect is more physiologic than other possible mechanisms which act by kinking and obstructing the urethra. The response to serial filling performed intraoperatively depends on urethral rigidity, reflects baseline SUI severity, and predicts postoperative results [ 23 ].…”

The effectiveness of adjustable trans‐obturator male system (ATOMS) in radiated patients is reduced: A propensity score‐matched analysis

“…There is increasing evidence that stretching membranous urethral length can be associated with PPI recovery 4 . However, the response to an increase in intraurethral pressure depends on urethral rigidity and is not exclusively determined by baseline incontinence severity 5 …”

ATOMS (Adjustable Trans-Obturator Male System) in Patients with Post-Prostatectomy Incontinence and Previously Treated Urethral Stricture or Bladder Neck Contracture

“…Unlike the fixed sling, it can even be used in patients with a partially damaged sphincter, and that enlarges its range of applications. The mode of action is a mixture of direct compression of the bulbar urethra and, in the case of good urethral elasticity, a distribution of pressure to the membranous urethra [ 8 ]. The scrotal port connected to the sub-urethral cushion allows simple adjustments by percutaneous puncture through the scrotal skin, which can be done even years after the device was originally implanted.…”