Urethral Sphincter Mechanism Incompetence (USMI)

Identifying ectopic ureters – tips and tricks: Ureteral ectopia (EU) is a congenital abnormality, in which one or both ureteral openings form with their termination located distal to the bladder trigone. Intramural and extramural phenotypes are recognised, with >95% of canine cases identified as intramural, whilst the majority of feline EU are extramural. Diagnosis may be straightforward in patients presenting with significant urinary incontinence at a young age, but may be challenging in patients with a more atypical presentation, or in those with only subtle abnormalities of their urinary tracts. This session covers the variable clinical presentation of patients with ectopic ureters, explains ultrasound findings that may increase your index of suspicion for this condition, how to optimise contrast imaging to highlight an abnormal ureter and more about our current gold standard of diagnosis, cystoscopy. This information should enable you to more confidently recommend additional diagnostic tests in the correct animals and avoid unnecessary testing in those patients unlikely to have this condition. More patients can then in turn receive appropriate treatment.

USMI when medicine fails: what next? Urethral sphincter mechanism incompetence (USMI) is the commonest cause of urinary incontinence in the bitch. Medical management is the first line treatment (usually with either an adrenergic agent (e.g. phenylpronolamine) or an oestrogenic agent (e.g. estriol). The majority of bitches have a good response to these, but other treatments need consideration in a minority of cases. Before surgery is planned, the clinician should review the diagnosis and consider underlying or secondary factors (such as obesity and urinary tract infection). If the diagnosis is confirmed and these have been considered, surgical management can be offered to the owners. There are several established surgical options (colposuspension, Artificial Urethral Sphincter placement, urethral sling), endoscopic management with urethral bulking agents and some less well established procedures (vaginectomy, vaginal septum transection). The session looks at each of these and make suggestions as to their application.