Hypothesis / aims of study
In the current era of controversy associated with mesh, urethral bulking injections are becoming an increasingly popular, low risk, minimally invasive treatment option for women with stress urinary incontinence (SUI). Despite this, little is known about their long-term effects.
"Deflux®" is a hyaluronic acid/dextranomer gel that is non-animal stabilised (NASHATM/Dx). With an established safety record and short-term efficacy for SUI, the drug is injected under direct vision using a cystoscope. Dextranomer microspheres of 80-200µm are utilised in the bulking process with hyaluronic acid acting as the transport compound.
This study evaluates the efficacy and long-term outcomes of Deflux as a urethral bulking agent when used in females with SUI.
Study design, materials and methods
Between 2001 and 2007, all women with SUI who underwent transurethral Deflux® urethral bulking injection were identified. All the women had mild to moderate incontinence, with a maximal pad usage of less than 3 per day.
Treatment success was defined as "dry at their initial 3 months follow up" or "only minor residual incontinence for which the patient does not desire further treatment".
Longer-term outcomes were ascertained from the patient's medical records in a retrospective manner or via telephone contact.
Results
142 women (mean 57 years, median 58 years) were identified to have undergone urethral bulking infections. Follow up was possible for 90% (128/142) of the patients, with 14 lost to follow up after their initial 3-month post-operative consultation.
Overall follow up from initial treatment was up to 13 years (mean 8.8 years, median 8.7 years).
51 women underwent repeat urethral bulking treatment during the follow-up period. 35 was due to insufficient response to their initial injection. 16 women had a repeat procedure due to recurrence of symptoms after a period of good symptom control.
63% (90/142) of women had a successful response to their first injection, with 38% (54/142) achieving complete resolution of incontinence and 25% (36/142) achieving what they felt to be a significant improvement with only minor residual incontinence. No patient reported worsening of SUI symptoms due to treatment.
For patients who underwent repeat injections, improvement was achieved in 71% (17/24) of patients who had a symptomatic response to the first injection, but only in 18% (2/11) of cases who did not have any improvement after their initial treatment.
94% (15/16) of cases had a successful second treatment if they had a complete resolution of symptoms after their initial treatment.
Duration of efficacy was on average 4.7 years (median 3.5 years, range 1-13 years) in those who achieved success in either their first or second treatment.
Interpretation of results
Deflux appears to be an effective treatment for women with mild to moderate SUI (up to a maximum of 3 days per day) with a duration of efficacy longer than previous studies. Our data however is limited by its retrospective design.