E-ISSN : 2757-7163
Materials and Methods: This retrospective cohort study involved 61 women diagnosed with SUI from 2022 to 2024. The study divided the patients into two groups: one comprising 32 patients who underwent TOT surgery and another comprising 29 patients who received PAHG injections. The key variables analyzed included demographic data, operation time, hospital stay, and patient satisfaction measured using the visual analog scale (VAS). Complications were recorded using the Clavien-Dindo classification. Statistical analyses were performed to identify the factors influencing the outcomes, including independent sample t-tests and regression models.
Results: The TOT group showed a higher treatment success rate, with 93.75% of patients having a resolution of SUI symptoms than the PAHG group (82.76%). PAHG demonstrated advantages in shorter operation times (mean difference, 8.31 minutes, p<0.001), absence of catheterization, and shorter hospital stays (mean difference of 20.24 hours, p<0.001). TOT was associated with higher rates of complications such as vaginal discharge (43.75%) and groin pain (28.12%), whereas the PAHG group reported no such complications.
Conclusions: TOT surgery provides higher success rates for SUI treatment; however, PAHG injections offer a viable, minimally invasive alternative with a lower risk of complications. Future research needs to involve larger sample sizes and include long-term follow-up to validate and refine these findings.
Recent complications in the surgical treatment of SUI have notably undermined confidence in traditional treatment methods. Mesh-based surgical approaches, such as transobturator tape (TOT), have been associated with serious complications including bladder injury and mesh erosion [2]. In this context, there is growing interest in alternative treatment modalities that are less invasive and reduce the risk of meshrelated complications.
Given the complications associated with traditional meshbased surgeries, our study turns to emerging alternatives such as PAHG (polyacrylamide Hydrogel) injections, aiming to evaluate their efficacy and safety. Degradation-resistant PAHG was approved by the Food and Drug Administration (FDA). This polymer gel contains 2.5% cross-linked polyacrylamide and 97.5% water for injection and is considered a promising option for treating urinary incontinence [3]. However, available data on the long-term efficacy and safety of PAHG injections are limited, making it imperative to compare this treatment option with other surgical methods.
This study aimed to compare the efficacy and safety of PAHG injections with those of TOT surgery for the treatment of SUI, to reveal the differences between these two methods, and to determine which of these treatment options is more appropriate in clinical practice. By filling the knowledge gaps in the existing literature, we aimed to provide evidence-based recommendations to improve patient satisfaction and outcomes in SUI treatment.
Eligibility Criteria
Patients included in the study did not differentiate between
mixed and pure urinary incontinence. Stress incontinence
was sufficient. Therefore, the presence of intrinsic sphincteric
deficiency (ISD) is not considered a valid criterion for exclusion of any procedure. Patients with recurrent urinary
tract infections, neurogenic bladder, neurological disorders
with severe functional impairment, or mental health problems
were excluded. Previous surgical interventions for stress urinary
incontinence were considered exclusion criteria for participation
in the study because they may confound the study results and,
therefore, were not included in the analysis. Minimally invasive
urodynamic studies were not conducted on uncomplicated
patients and were, thus, beyond the scope of this study. A visual
analog scale was used to evaluate patient satisfaction after the
procedure.
Treatment Decision Criteria
The decision to perform TOT or administer PAHG injections
was based on a combination of clinical evaluations and patientspecific
factors. Key considerations included:
Urethral Mobility: Patients with significant urethral hypermobility (as indicated by a Q-tip test angle >30°) were more likely to undergo TOT due to its higher efficacy in such cases.
Patient Preferences: Patients who desire a less invasive option with shorter recovery times were guided toward PAHG injections.
Body mass index (BMI) and comorbidities: TOT was preferred for patients with higher BMI (>35) or those who required greater structural support, while PAHG injections were recommended for patients with lower BMI or those unsuitable for surgical procedures due to comorbidities.
Previous Treatment History: Since no patients had prior treatments for SUI in this study, all interventions were considered first-line. Patients with contraindications for anesthesia or surgery were prioritized for PAHG injections.
Physician Assessment: The attending physician's clinical judgment, based on the patient"s medical history, physical examination, and risk-benefit analysis, played a crucial role in the final decision.
Ethical Considerations
Patients were apprised of the objective of the surgical
operation and the potential risks and advantages associated with
the procedures involved. Prior to and following the surgical
intervention, the patients were informed that the obtained data
could be used in a scientific study by safeguarding their personal
information, and they provided written informed consent before
the procedures commenced. This study adhered to the ethical
guidelines of the Declaration of Helsinki and was approved by
the Ethics Committee of Burhan Nalbantoğlu State Hospital
(Number: YTK1.01, project code 29/24).
Treatment and Follow-up Protocol
The trans-obturator type (out-in technique) procedure was
applied to all patients. Polyacrylamide hydrogel injection was
performed using a product-specific endoscope, endoscopy kit,
and injection needle (23-gauge), and 2-3 cc was injected at 3-4
distinct locations at the junction of the bladder neck and urethra.
The primary objective was to eradicate stress urinary incontinence as a measure of success. The patients" postoperative 6th-week stress incontinence was assessed via telephone. Bladder overactivity following the procedure is regarded as a complication in patients diagnosed with pure stress incontinence. Postoperative satisfaction was assessed using a visual analog scale. The global evaluation scale indicated that the treatment success had a response rate exceeding 50%. During the evaluation, patients were questioned about their inclination to submit themselves to the procedure again and recommend it to their friends.
Data Analysis
A power analysis was performed using G-power software
to evaluate the validity of the study and dependability of the
outcomes obtained. In the power analysis, the effect size (d) was
determined to be 0.8, which indicates that there was a mediumhigh-
level effect in our study. According to the power analysis
results, the probability of a type I error (α) was 8.61%, the
probability of a type II error (β) was 8.61%, and the statistical
power (1-β) was 91.38. The categorical data encompassed the
nature of the treatment, including TOT/PAHG, as well as the
classification of urinary incontinence, such as mixed or pure.
Moreover, it contains information on potential complications,
including vaginal discharge and groin pain. The quantitative
data examined in this study comprised several variables, such
as patient age, body mass index (BMI), frequency of urinary
incontinence episodes per day, operation time, hospital stay, and
visual analoge scale (VAS) satisfaction score. These variables
were analyzed using descriptive statistics, and an independent
sample t-test was used to compare the results between the
TOT and PAHG groups. The tables provide a summary of the
descriptive statistics. Categorical data were expressed as numbers
(n) and percentages, whereas quantitative data were presented
as mean ± standard deviation (SD). Regression and correlation
tests were conducted to determine the factors influencing the
treatment outcomes. Data analysis was performed using SPSS
version 28.0 software.
Table 1. Characteristic features of the surgical technique groups
The treatment success rate was 30 (93.75%) in patients who underwent TOT. In 2 (6.25%) patients, no incontinence was observed with provocation in the lithotomy position; however, incontinence was detected while standing. Urinary incontinence in five (17.24%) patients in the PAHG group resolved completely a few days after the procedure but returned afterward. Three of the five patients with urinary incontinence after PAHG injection had a BMI > 35.
Both methods were assessed in terms of operative time, postoperative urethral catheter duration, and length of hospital stay by using an independent t-test. The mean difference in operative times was 8.31 minutes. According to Levene's test, the p-value was 0.054, suggesting that the variances were equal. Therefore, the mean operative time was notably shorter in the PAHG group (p <0.001). The PAHG group did not experience catheterization, whereas the TOT group was catheterized for 22.53 hours. There was a statistically significant difference between the two groups regarding catheterization (p<0.001). In addition, there was a mean difference of 20.24 hours between postoperative hospitalization times, and the TOT group had a longer hospital stay (p<0.001). Statistical evidence revealed that the hospitalization requirements of the TOT group were more significant.
In a cross-tabulation analysis conducted using SPSS and employing the global response scale, 20 out of 32 patients in the TOT group were classified as "4," 10 as "5," and two as "2". For the PAHG group, 2 of 29 patients received a score of "0", 3 received a score of "2", 7 received a score of "4", and 17 received a score of "5". The results indicated a statistically significant difference between the two groups (p = 0.021). The postoperative VAS satisfaction score for the TOT group was 7.81±1.06, while that for the PAHG group was 8.06±1.36. Since the postoperative VAS satisfaction scores did not follow a normal distribution, the Mann-Whitney U test was used to compare the two groups, and no significant difference was observed between them (p=0.12).
The results of the linear regression analysis were used to determine the factors that influenced the VAS satisfaction score. The p-value for treatment method was 0.835, while the p-value for age was 0.019. As age increased, the VAS satisfaction scores also increased. The p-values for the number of urinary incontinence episodes and the duration of urinary incontinence were 0.213 and 0.630, respectively, indicating that these variables did not notably affect the VAS satisfaction score. The p-value for BMI was 0.675, suggesting that this variable had no significant impact on the VAS satisfaction score. The factors that influenced treatment success were analyzed using a logistic regression model. The results showed that the variables were collectively significant (Overall Statistics: p=0.003). Specifically, the Treatment Method (p=0.014), age (p=0.548), number of Urinary Incontinence episodes (p=0.094), duration of Urinary Incontinence (p=0.293), and BMI (p=0.014) were all found to be statistically significant.
None of the patients had urinary retention or required clean intermittent catheterization. Of the 32 patients who received TOT after 7 days, 14 (43.75%) were found to have vaginal discharge (Clavien-Dindo grade II). The patients were administered vaginal antibacterial suppositories. Of the 32 individuals who underwent TOT, 9 (28.12%) experienced pain in the groin area (Clavien-Dindo grade I). The patients were treated with nonsteroidal anti-inflammatory drugs (NSAIDs) without requiring physical therapy or additional medical or surgical intervention. Twenty-three patients with TOT experienced postoperative vaginal bleeding in the form of spotting that soiled the pads or underwear. No bladder injury or mesh erosion was detected in any of the patients in the TOT group during the follow-up period (Table 2).
The use of specific equipment for PAHG applications makes this method easy and standardized [7]. The use of PAHG may be considered for patients with hip issues who are placed in a restricted lithotomy position during mid-urethral sling procedures as it has demonstrated comparable treatment outcomes. In our case series, three patients were referred to the PAHG by their surgeons for this specific purpose.
When evaluated in terms of patient satisfaction, there was no statistically significant difference between the two methods; however, the satisfaction rates in the PAHG group tended to increase with age. In the literature, satisfaction rates with PAHG injections have been reported to range between 64% and 90% [4], which is consistent with our findings [4,8,9]. Despite the high success rates of the TOT method, the low complication rates and minimally invasive nature of PAHG injections may support the preference for this method in certain patient groups. However, in contrast to more invasive methods such as TOT and tension-free vaginal tape (TVT), no disparity in satisfaction rates has been detected in most studies [4].
Remarkably, patients with high BMI benefited less from PAHG injections, suggesting that the efficacy of this method may be related to BMI. However, the fact that patients with similar BMI benefited notably from TOT suggests that TOT may be more effective in this patient group. Although the sample size of our study was small, this finding suggests that BMI may be an important factor in treatment selection, and this issue should be examined in greater depth in studies with larger sample sizes.
The effect of surgical experience on treatment outcomes was an important finding of our study. The surgeons" long years of experience with the TOT method may explain the high success rates of this method, whereas less experience with PAHG injections may have led to lower success rates. This suggests that surgical experience and skill can notably influence treatment outcomes, especially with new or less commonly used methods [10,11].
With regard to complications, higher rates of vaginal discharge and groin pain were observed in the TOT group. These complications may be related to the invasive nature of TOT, and surgical techniques should be revised to reduce such complications [10,11]. The absence of such complications in the PAHG group suggests that the PAHG injections have an advantageous safety profile. Nevertheless, it is reasonable to anticipate low complication rates by carefully selecting the patients in the PAHG group [6,12]. Unfortunately, this study did not include long-term follow-up data. Long follow-up periods of up to 7 years have been documented in previous studies for PAHG patients with PAHG and are consistent with our observations [13].
This study has some limitations. First, the relatively small sample size limited the generalizability of our findings. Furthermore, the inhomogeneity of the patients and lack of separation between mixed-type and pure SUI cases may have affected the accuracy of the results. Furthermore, the absence of long-term follow-up data in this study introduces uncertainty, particularly concerning the long-term efficacy and safety of PAHG injections. Moreover, the fact that a single surgeon performed all the surgical procedures could have influenced the outcomes. Notably, while the surgeon had 17 years of experience in the TOT group, they had only two years of experience in the PAHG group. This disparity in experience may have affected the results and should be considered when interpreting the findings. Considering these limitations, randomized controlled trials with larger sample sizes and long-term outcomes should be conducted in the future [6].
Ethics Committee Approval: This study was performed according to the Helsinki Declaration and with permission from the local ethics committee of Burhan Nalbantoğlu State Hospital (Number: YTK1.01, project code 29/24).
Informed Consent: An informed consent was obtained from all the patients.
Publication: The results of the study were not published in full or in part in form of abstracts.
Peer-review: Externally peer-reviewed.
Authorship Contributions: Any contribution was not made by any individual not listed as an author. All authors read and approved the final version of the manuscript. Concept – N.B., F.E.; Design – N.B., F.E.; Supervision – N.B., F.E.; Resources – N.B., F.E.; Materials – N.B., F.E.; Data Collection and/or Processing – N.B., F.E.; Analysis and/or Interpretation – N.B., F.E.; Literature Search – N.B., F.E.; Writing Manuscript – N.B., F.E.; Critical Review – N.B., F.E.
Conflict of Interest: The authors declare that they have no conflicts of interest.
Financial Disclosure: The authors declare that this study received no financial support.
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