INTRODUCTION: The conventional video colpo-cysto entero defecography describing the morpho- functional imaging features, physiological and pathological of the recto-anal region and pelvic floor . It represents the gold standard examination for the identification and staging of morphological and functional disorders of the recto-anal region and pelvic floor in evacuation dysfunctions. MATERIALS AND METHODS: Between January 2010 to January 2013 88 patients underwent STARR procedure for obstructed defecation syndrome (ODS) caused by single rectocele or internal rectal intussusception. We retrospectively analyzed the collected data,in particular we reviewed the defecography results before surgery. RESULTS: At defecography imaging , 30 patients (34 %) had an anal canal opening between 0 and 5 seconds, 44 (50 %) between 6 and 10 seconds and 14 patients (16 %) over 10 seconds at defecography imaging. The defecography showed an enterocele in 30 patients (34 %) The enterocele was functional in 25 (28,4 %) and stable in 5 (5,6 %) patients. 53 patients have a II‹ rectocele (60,2 %) and 35 patients a III‹ rectocele (39,7 %). The average preoperative ODS score was 14 . The average ODS score revaluated at 1 year was 3.1, 4.3 at 3 years an 6,4 after 5 years. The improvement of the ODS score was lower in the subgroup of patients presenting a slow opening of the anal canal (> 10 sec): 7.5 at one year, 9.1 at 3 years and 11 after 5 years follow-up. Also in the subgroup of patients with stable enterocele (5,6 %) the improvement was less evident: 6.7 at 1 year, 8 at 3 years and 9.7 after 5 years follow-up. DISCUSSION AND CONCLUSION: We have observed that a coexistence of a long opening time of the anal canal and / or the presence of a stable enterocele are factors that significantly reduce the effectiveness of the surgery leading over time to ODS score values close to those present before surgery. In the fisrt case we suggest a pre and post-operative perineal physiotherapy, in the second case a Dougla’s platsy