Avaliação comparativa entre o ultrassom transvaginal/transretal e a ecodefecografia no diagnóstico da evacuação obstruída

Abstract

Evaluate the applicability of a novel technique using dynamic tridimensional transvaginal / transrectal ultrasound as an alternative diagnostic method to evaluate the obstructed defecation, comparing with Echodefecography. It is a prospective and comparative exam, involving female patients with obstructed defecation, mean Wexner constipation score higher than 6. All patients were submitted to dynamic tridimensional ultrasound by two different techniques to identify all the obstructed defecation dysfunctions. The Echodefecography was used as the standard method to evaluate the dynamic tridimensional transvaginal / transrectal ultrasound technique. After introducing 120 mL gel into the rectum, it was used the transvaginal approach to evaluate the anorectal angle at rest and during evacuatory effort to identify the Puborectal muscle relaxation or paradoxical contraction (Anismus). Using the transrectal approach, it was evaluated the presence of different sizes of Rectocele, Intussusception and Enterocele / Sigmoidocele during evacuatory effort. All data were compared. It was used Student t Test and Lee Kappa Correlation Coefficient for statistical analysis. It was calculated efficacy, sensibility, specificity, positive predictive valour, negative predictive valour of the combined transvaginal / transrectal ultrasound technique to identify each dysfunction. Thirty three female patients, mean age 48 years old, mean Wexner constipation score 10 (range 7 - 14) were included. There was substantial concordance between both exams to identify Anismus and normal relaxation (K=0.683). There was significant reduction in the anorectal angle in 19 patients submitted to Echodefecography (84.79 ° ± 1.008 x 80.11° ± 1.725), with mean change of 5° ( ±4,738 ) and in 17 patients evaluated by the transvaginal / transrectal Ultrasound (120.5° ± 2.378 x 109.6° ± 3.449), with mean change of 10,82°±8,164. The difference between the angles was significantly higher in patients evaluated by transvaginal / transrectal Ultrasound when compared with Echodefecography (15.45° ± 1.539 x 7.182° ± 0.9804) (p=0,0001). It was identified Rectocele in 27 patients and absent in 6 in both techniques used, demonstrating almost perfect concordance index (K=1.0). It was demonstrated 12 patients with grade III Rectocele, 9 with grade II and 3 with grade I in both techniques used, demonstrating almost perfect concordance index for different grades of Rectocele (K= 0.812) (K=0.857) (K= 0.841). There was disagreement in only 3 patients between both methods, 2 with grade III in Echodefecography and grade I and II in transvaginal / transrectal Ultrasound. Another one with grade II in Echodefecography and grade III in transvaginal / transrectal Ultrasound. Comparing both methods, there was no statistically significant difference with respect to the degree of Rectocele (1,076±0,6838 x 1,139±0,7267) (p=0,7153). There was almost perfect concordance index in identification of rectal Intussusception (K= 0.914) and Enterocele / Sigmoidocele (K= 0.659). It was demonstrated valor higher than 87,6% of efficacy, sensibility, specificity, positive predictive valor, negative predictive for each evaluated dysfunction. In conclusion, the technique using dynamic tridimensional transvaginal / transrectal Ultrasound showed high concordance index with Echodefecography and can be used as an alternative method to evaluate patients with obstructed defecation symptoms.