Utilidad de la ultrasonografía introital en incontinencia de orina de esfuerzo, curva ROC / Usefulness of introital ultrasonography in stress incontinence of urine, ROC curve

RESUMEN

Para determinar si existe una variable en ultrasonografía introital que pueda utilizarse para distinguir mujeres con incontinencia de orina de esfuerzo (IOE) y mujeres continentes, realizamos este estudio de tipo diagnóstico prospectivo de un solo centro involucrando 24 mujeres continentes y 43 mujeres con IOE todas voluntarias seleccionadas según los criterios de inclusión- exclusión, se realizó ultrasonografía introital a todas ellas consignando diversos parámetros de distancias y ángulos en reposo durante Valsalva y Kegel, de todas las variables analizadas la altura H durante Valsalva fue la mejor para distinguir entre pacientes incontinentes y continentes siendo 15.5 mm el valor de corte según la curva de ROC correspondiente.

ABSTRACT

Objective: To determine if there is a variable on introital ultrasonography (IUS) that can be used to distinguish between women with stress urinary incontinence and continent women. Patients and methods: This single centre, prospective, diagnostic study, comprised 24 women continent and 43 incontinent who were all appropriately informed volunteers selected according to the inclusion criteria. IUS with a transvaginal probe was performed on all women; the measurement plane was standardized and coordinates were obtained at rest, on straining and Kegel. Several distances and angles were measured to determine if any provided an objective distinction between continent and incontinent women. Results: Among all the IUS variables assessed, the height H (the vertical distance from a horizontal line drawn at the lower border of the symphysis and the bladder neck) on straining (Valsalva) was the best for distinguishing continent and incontinent women. The receiver operating characteristic curves showed that with a threshold of 15,5 mm, the height H on straining had a sensitivity of 70.8 percent and a specificity of 82.9 percent for detecting Stress Urinary incontinence (SUI). The sliding (calculated as the difference between the height H at rest and under stress) and the height H at rest could also discriminate, but with lower significance. Conclusions: IUS is an important tool for diagnosing SUI; there are three independent variables, one dynamic (sliding) and two static (height H at rest and straining), that can be used to distinguish between continent women and those with SUI. The height H at Valsalva is the most reliable, as it has the highest sensitivity and specificity. We think that the simplicity, low financial cost and reliability of IUS could allow it to be a routine procedure for physicians working in incontinence units.