Benign anorectal disorders

Problem Investigated:A multitude of benign disorders affect the anorectal complex often resulting in significant morbidity. For many of these conditions the pathophysiology and clinical management continue to be debated. This is particularly so for anal fissures, anal incontinence and pelvic floor dysfunction.Procedures Followed:A series of clinical trials was performed.Anal Fissure: Two current management regimes for chronic anal fissure, Glyceryl Trinitrate and Botulinum Toxin, were prospectively assessed for manometric and clinical outcome. A new treatment regime, inducible nitric oxide, was prospectively assessed in an animal model and a new manometric observation in anal fissure patients, the Fast Wave, was validated.Anal Incontinence: The magnitude of the problem and the relative role of several previously identified risk factors was assessed from a manometric data-base. The impact of a standard treatment for Crohn's disease, the seton, on anal continence was assessed via a retrospective cohort study. The long-term outcome of dynamic graciloplasty and re-do anal sphincter repair, two previously accepted treatments for anal incontinence, were also assessed retrospectively. A new intervention for treating anal incontinence, the magnetic ‘Chair’, was prospectively trialed in incontinent patients.Pelvic Floor Dysfunction: A new treatment option for rectocoele, the laparoscopic repair, was compared with an accepted treatment option, the transanal repair via a matched cohort study. A further group of patients with multiple symptoms of pelvic floor dysfunction undergoing the same laparoscopic technique were then prospectively assessed for functional outcome across the pelvic floor compartments.General Results:Anal Fissure; The manometric effects of both glyceryl trinitrate and botulinum toxin, demonstrated in this thesis would imply that their mode of impact on the anal sphincter is other than that of anal pressure reduction. Fissure healing is dependent upon the pre-treatment anal resting pressure and fissure grade, not anal pressures following treatment. Inducible nitric oxide does not increase nitrate levels in the rat internal anal sphincter. A new manometric wave form in the hypertonic internal anal sphincter, the Fast Wave, has been validated.Faecal Incontinence; Faecal incontinence is multi-factorial. However, obstetric birth injuries are the most significant factor predisposing to faecal incontinence following age. Furthermore current government policies are failing to address the problem. The dynamic graciloplasty provides symptomatic long-term relief in only 16 percent of patients and results in significant co-morbidity in most patients. Re-do anal sphincter repair provides relief in 60 percent of patients without further side effects. The use of a seton in Crohn’s perianal disease prevents deterioration of patient continence. Extracorporeal magnetic stimulation, the Chair, may provide significant relief for patients with faecal incontinence.Pelvic Floor Dysfunction: The laparoscopic posterior compartment repair provides relief of bowel symptoms in 31 percent of patients. This does not compare favourably with the transanal long-term symptomatic improvement of 67 percent. The results of the laparoscopic pelvic floor repair in patients with multiple symptoms of pelvic floor dysfunction is disappointing, particularly for bowel and bladder symptom improvement.Major Conclusions: This thesis questions the accepted pathophysiology of anal fissure, highlights the long-term implications of obstetric childbirth injuries on faecal continence and raises concerns about current management strategies for faecal incontinence and pelvic floor dysfunction