In the first study, Canadian and American researchers implanted the artificial anal sphincter in 112 patients (mean age, 49 years) with a fecal incontinence score of ≥ 88 (scale, 1-120).
The participants were then evaluated 6 and 12 months after implantation.
A total of 384 device-related or potentially device-related adverse events were reported in 99 enrolled patients.
Of these events, 246 required no intervention or only non-invasive intervention.
However, 73 revisional operations were required in 46% of the implanted patients.
Infection rate necessitating surgical revision was 25%.
A total of 41 patients (37%) have had their devices completely explanted, of which 7 have had successful reimplantations.
In patients with a functioning neosphincter, improvement in quality of life and anal continence was documented.
At 6 months follow-up, mean matched fecal incontinence score was improved from 105 preimplant to 51 postimplant.
At 12 months follow-up, mean matched fecal incontinence score had improved further, to 48.
A successful outcome was achieved in 85% of patients with a functioning device. Intention to treat success rate was 53%.
Dr W. Douglas Wong, of the Memorial Sloan-Kettering Cancer Center, New York, USA, concluded on behalf of his team, "Although morbidity and the need for revisional surgery are high, the artificial anal sphincter can improve anal incontinence and quality of life in patients with severe fecal incontinence."
In the second study, a group from Madrid, Spain, implanted the Acticon Neosphincter in 53 patients (median age, 46 years) with total anal incontinence.
Physiologic testing was conducted before and after the operation (mean follow-up, 26.5 months).
Quality of life was also assessed in 25 of the patients.
The researchers found that perioperative events occurred in 26% of the patients. These were abnormal bleeding (n = 7), vaginal perforation (n = 4), rectal perforation without apparent contamination (n = 2), and unobserved urethral perforation (n = 1).
Early complications were mainly related to sepsis in 15% of patients and also wound complication in 15%.
| Complication rates were high in patients who had the artificial sphincter implanted.
| Diseases of the Colon & Rectum |
Sepsis could not be statistically associated with any of the variables studied.
However, wound separation was associated with fibrosis and tension of the wound.
Late complications included cuff and/or pump erosion in 18% of patients, infection in 6%, impaction in 22%, pain in 8%, and mechanical failures in 4%.
Nonetheless, none of those complications showed a statistical association with any of the variables studied.
Of the artificial sphincters, 19% had to be explanted due to septic or skin complications.
It was discovered that normal continence was achieved in 65% of patients and continence to solid stool in 98%.
The Cleveland Clinic score of incontinence (0-20, maximal incontinence) changed from 17 preoperatively, to 4 postoperatively.
In addition, resting and squeeze pressures changed significantly after activation.
Furthermore, quality of life measured in 4 subscales was found to change significantly in all the subscales.
Dr Jose M. Devesa, of the University Hospital Ramón y Cajal, Madrid, said on behalf of the group, "The artificial anal sphincter restores continence to solid stool in almost all severely incontinent patients, two-thirds of whom achieve practically normal continence, and also significantly improves quality of life.
"Infection and skin erosion are the cause of the majority of explants."
"However, no predictable factors of functional success could be found in this study," it was concluded.