In 2014, the American Food and Drug Administration  FDA approved the indication of the non-invasive, Er:YAG laser in the field of urogynecology. The Er:YAG laser has a SMOOTH mode, which emits laser pulses from the vaginal probe, releasing pulsatile-heat to the vaginal wall to shorten the intermolecular cross-links of collagen, shrinking the collagen fibril, and enhancing collagen production. Furthermore, FDA has announced warnings regarding their use. Therefore,the risks of these devices should be evaluated, and patients should be informed prior to use.There have been publications on the efficacy of laser therapy in stress incontinence.  Overactive bladder (OAB) symptoms may coexist in 21.6–46.9% of patients with urinary incontinence. Previous studies reported that only 50–71% of patients have improved symptoms  of OAB or urgency incontinence after sling surgery for SUI one year later. Thus we aimed to evaluate the efficacy of the non-invasive Erbium:YAG laser in the treatment of urgency incontinence  in women with stress urinary incontinence.

Between April, 2015 and February 2016, 67 consecutive women with  stress-predominant mixed urinary incontinence were included.Before and 6 months after treatment, each patient’s baseline The characteristic data was collected and a personal interview was conducted using the following battery of questionnaires: Incontinence Questionnaire–Short Form (ICIQ-SF)
, Urogenital Distress Inventory 6 (UDI-6), Incontinence Impact Questionnaire 7 (IIQ-7), Overactive Bladder Symptom Score (OABSS) , Pelvic Organ Prolapse Distress Inventory 6 (POPDI-6) and Female Sexual Function Index (FSFI) .The information gained was used to assess each patient’s degree of urinary incontinence and its impact on their quality of life.The vaginal pressure at rest and during contraction and pad test were measured  prior to initial treatment and repeated 6 months after laser treatment.The average and maximal pressures and the period of time during contraction were also calculated.If patients did not adhere to their scheduled follow-up appointments, their recordings were excluded from the study.

We included 67 patients with a mean age of  40.6± 8.8 years.  About SUI, twenty-four (24/37) was cured and sixteen (16/67) was improved. Six months after therapy, mean 1-h pad test significantly decreased (P = 0.030).The efficacy of laser for SUI is 74.6% (50/67). Thirty-nine percent  of these patients felt urgency incontinence improved and thirty-three percent of frequency exhibited improvements.  Significant improvement in OAB symptoms in OABSSS  (7.0 ±2.0 ==> 3.5± 2.1,p=0.00) and associated questionnaires were noted post treatment.The mean vaginal pressure not significantly improved (P = 0.162) . The total scores of  FSFI with lubricatiaon, satisfication and pain domains were significantly improved (P=0.034)  No major adverse effects were noticed.Due to SUI ofen being related to pelvic foor muscle dysfunction, we were inquisitive about a possible applicationusing the Er:YAG laser to increase pelvic muscle tone.Disappointingly, the assessed muscle tone did not show asignifcant increase after treatment.The  synergistic benefit may be achieved with a combined treatment regimen using the Er:YAG laser in combination with pelvic muscle exercises, thereby allowing for a different mechanism for SUI improvement.

In comparison to other studies, our OABSS and POPDI scores were significantly decreased.Women with
SUI usually have OAB problem and most parous women demonstrated some degree of cystocele. The mechanism has been investigated that funneling of the proximal urethra urine enters the proximal urethra and then produces sensory
stimulation resulting in a reflex of bladder contraction with OAB. Based on the hypothesis ,the  cure of SUI can be related the improvement of urgency incontinence.  The dryness of vaginal wall of genitourianry symptom of menopause can resulted to urinary frequency or urgency.The vaginal laser had the collagenensis effect of vaginal wall and further moisture of the vagina was found. Our reports demonstrated the collage remodeling made  lubrication and pain domains of FSFI significantly improve.

Er:YAG vaginal  laser procedure is a minimal invasive  procedure and seems to be a efficacious treatment  for patients with SUI and partially effective for urgency incontinence among women with  stress-predominant mixed urinary incontinence.

H. Abrahamse, “Regenerative medicine, stem cells, and low- level laser therapy: future directives,” Photomedicine and Laser  Surgery, vol. 30, no. 12, pp. 681-682, 2012.
Y.-W. Tien, S.-M. Hsiao, C.-N. Lee, and H.-H. Lin, “Efects of laser procedure for female urodynamic stress incontinence on pad weight, urodynamics, and sexual function,” International Urogynecology Journal, vol. 28, no. 3, pp. 469–476, 2017.
G. Geirsson and M. Fall, “Refex interaction between the proximal urethra and the bladder: A clinical experimental study,” Scandinavian Journal of Urology, vol. 33, no. 1, pp. 24– 26, 1999.