Is routine endoanal ultrasound useful in anal fistulas? ¿Es útil la ecografía endoanal de rutina en las fístulas perianales?

Objective: to evaluate the effectiveness of endoanal ultrasound with hydrogen peroxide enhancement in the assessment of anal fistula (tract and internal opening), and to value the utility of this examination for anal or perianal suppuration when performed by a colorectal surgeon trained in this technique. Patients: endoanal ultrasound was performed in 103 patients with anal or perianal suppuration. Twenty patients were excluded: 9 had the external opening closed, and 11 had cryptoglandular abscesses. All ultrasound scans were performed by the same explorer using a B&K Diagnostic Ultrasound System with a 7 MHz endoprobe. The examination was based on the identification of the three anal planes, then hydrogen peroxide was infused and the procedure was repeated. Results: out of 83 patients included, 11 had a perianal sinus and 72 an anal fistula. In all fistulas the main tract was found: 24 were inter-sphinteric (33.33%), 33 trans-sphincteric (45.83%), 3 supra-sphincteric (4.17%), and 12 extra-sphincteric (16.67%). An internal opening was identified in 69 (95.83%). Conclusions: endoanal ultrasound with hydrogen peroxide enhancement is an effective examination to visualize fistulous tracts and internal openings. We think it is highly useful for anal or perianal suppuration to identify abscesses, to recognize a perianal sinus, to check the sphincteric condition, and to plan subsequent surgery.<br>Objetivo: evaluar la efectividad de la ecografía endoanal contrastada con inyección de agua oxigenada para establecer la topografía fistulosa (trayecto y localización del orificio interno) y valorar la conveniencia de esta exploración en la supuración anal o perianal cuando es realizada por un cirujano general dedicado a coloproctología y entrenado en esta técnica. Pacientes: se hizo ecografía endoanal a 103 pacientes con supuración anal o perianal. Se excluyeron 20 pacientes del estudio: 9 tenían el orificio externo de la fístula cerrado y 11 presentaban abscesos de origen criptoglandular. Todas las ecografías fueron hechas por el mismo explorador utilizando un ecógrafo B&K con sonda rotatoria de 7 MHz. La exploración consistía en identificar los tres planos ecográficos del canal anal, inyectar agua oxigenada por el orificio externo y repetir el procedimiento. Resultados: de los 83 pacientes incluidos, 11 resultaron ser sinus y 72 fístulas perianales. De estas se localizó el trayecto principal en todas, identificándose 24 interesfinterianas (33,33%), 33 transesfinterianas (45,83%), 3 supraesfinterianas (4,17%) y 12 extraesfinterianas (16,67%). Se localizó el orificio interno en 69 (95,83%). Conclusiones: la ecografía endoanal realzada con agua oxigenada es un método efectivo para visualizar el trayecto y el orificio interno de las fístulas perianales. Creemos que resulta de gran utilidad en todos los casos de supuración anal o perianal para localizar colecciones, reconocer sinus perianales, conocer el estado de los esfínteres y planificar la cirugía

Is routine endoanal ultrasound useful in anal fistulas?

Objective: to evaluate the effectiveness of endoanal ultrasound with hydrogen peroxide enhancement in the assessment of anal fistula (tract and internal opening), and to value the utility of this examination for anal or perianal suppuration when performed by a colorectal surgeon trained in this technique. Patients: endoanal ultrasound was performed in 103 patients with anal or perianal suppuration. Twenty patients were excluded: 9 had the external opening closed, and 11 had cryptoglandular abscesses. All ultrasound scans were performed by the same explorer using a B&K Diagnostic Ultrasound System with a 7 MHz endoprobe. The examination was based on the identification of the three anal planes, then hydrogen peroxide was infused and the procedure was repeated. Results: out of 83 patients included, 11 had a perianal sinus and 72 an anal fistula. In all fistulas the main tract was found: 24 were inter-sphinteric (33.33%), 33 trans-sphincteric (45.83%), 3 supra-sphincteric (4.17%), and 12 extra-sphincteric (16.67%). An internal opening was identified in 69 (95.83%). Conclusions: endoanal ultrasound with hydrogen peroxide enhancement is an effective examination to visualize fistulous tracts and internal openings. We think it is highly useful for anal or perianal suppuration to identify abscesses, to recognize a perianal sinus, to check the sphincteric condition, and to plan subsequent surgery