Pain Related to Intradetrusor BotulinumtoxinA: A Randomized Clinical Trial

IMPORTANCE

OnabotulinumtoxinA (BTX-A) is an effective treatment for overactive bladder (OAB), but few studies have been done to evaluate injection techniques.

OBJECTIVE

The primary objective was to evaluate procedural discomfort between 2 commonly used injection techniques for BTX-A.

STUDY DESIGN

This was a single-blinded, randomized clinical trial of women undergoing injection of 100 U BTX-A for idiopathic OAB. Patients were randomized to 5 mL/5 injection or 10 mL/10 injection groups. Bladder pain was assessed by a validated Numeric Pain Rating Scale. Overactive bladder symptoms were assessed with a standardized questionnaire (Overactive Bladder Questionnaire Short Form). Patient satisfaction, treatment efficacy, and adverse events were assessed at 30 days after procedure.

RESULTS

One hundred eight patients were randomized to 52 in the 5 mL/5 injection arm and 56 in the 10 mL/10 injection arm. Mean procedural pain scores were 3.2 (±2.3) in the 5 mL/5 injection group versus 3.6 (±2.1) in the 10 mL/10 injection group (P = 0.21). No difference was found when categorizing pain scores into ordinal outcomes of low (P = 0.55), medium (P = 0.70), and high (P = 1.0) or a binary outcome of low (P = 0.55) versus medium + high (P = 0.55). Multivariate analyses did not effect statistical significance between the 2 groups for the ordinal outcome (odds ratio = 1.86; 95% confidence interval = 0.77 = 4.52; P = 0.17) or the binary outcome (odds ratio = 1.81; 95% confidence interval = 0.68-4.77; P = 0.28). No difference was observed between overall patient satisfaction, global impression of improvement, Overactive Bladder Questionnaire Short Form scores, or adverse outcomes.

CONCLUSIONS

Procedural discomfort related to BTX-A injection for idiopathic OAB was not different between 2 injection protocols. Overall satisfaction was high for both groups, and there was no difference in symptom scores or adverse events.

Polystyrene-poly(ethylene oxide) diblock copolymer: the effect of polystyrene and spreading concentration at the air/water interface

Polystyrene-block-poly(ethylene oxide) (PS-PEO) is an amphiphilic diblock copolymer that undergoes microphase separation when spread at the air/water interface, forming nanosized domains. In this study, we investigate the impact of PS by examining a series of PS-PEO samples containing constant PEO (~17,000 g·mol(-1)) and variable PS (from 3600 to 200,000 g·mol(-1)) through isothermal characterization and atomic force microscopy (AFM). The polymers separated into two categories: predominantly hydrophobic and predominantly hydrophilic with a weight percent of PEO of ~20% providing the boundary between the two. AFM results indicated that predominantly hydrophilic PS-PEO forms dots while more hydrophobic samples yield a mixture of dots and spaghetti with continent-like structures appearing at ~7% PEO or less. These structures reflect a blend of polymer spreading, entanglement, and vitrification as the solvent evaporates. Changing the spreading concentration provides insight into this process with higher concentrations representing earlier kinetic stages and lower concentrations demonstrating later ones. Comparison of isothermal results and AFM analysis shows how polymer behavior at the air/water interface correlates with the observed nanostructures. Understanding the impact of polymer composition and spreading concentration is significant in leading to greater control over the nanostructures obtained through PS-PEO self-assembly and their eventual application as polymer templates.