Abstract Background Strictureplasty techniques were developed to limit the risk of short bowel syndrome in Crohn’s disease (CD) patients with affected small intestine. In the setting of extensive small bowel disease, long strictures might be treated with modified side-to-side isoperistaltic strictureplasty (SSIS). We studied long-term outcomes in patients who underwent SSIS and evaluated if radiological features on MR enterography (MRE) predict them. Methods This retrospective study included CD patients who underwent SSIS, for whom preoperative and six-month postoperative MRE were routinely performed. Simplified MARIA (MARIAs) score, considering wall thickness, edema, fat stranding and ulcers (score >1 active CD; maximum 5) was used. Improvement in maximal wall thickness was defined as decrease of at least 30% from baseline. Deep remission was defined as absence of symptoms and endoscopic remission (mRutgeerts score ≤i1), and clinical recurrence as occurrence of new symptoms confirmed by endoscopy (mRutgeerts score ≥i2b) or radiology (new strictures/inflammation) requiring treatment. Clinical data were collected from medical records. The correlation between recurrence and features within the MARIAs score was assessed. Results Thirty CD patients underwent SSIS and had pre- and six-month postoperative MRE (table). Immediately after surgery, 13 (43.3%) patients were continued or initiated on advanced therapy. Over a median [IQR] follow-up of 7.4 [3.3-9.3] years, 17 (56.7%) patients showed clinical recurrence of whom 6 (20.0%) needed surgical reintervention (figure). Deep remission was observed in 8 (26.7%) patients. Preoperatively, all patients had a maximum MARIAs score of 5. After surgery, the median [IQR] change in MARIAs score was 0.0 [0.0-0.8]. Cox regression analysis showed no association between decrease in overall MARIAs score, nor separate components of this score, with clinical or surgical recurrence free survival. Wall thickness decrease of >30%, observed in 15 (50%) patients, showed a trend for clinical recurrence free survival (p=0.098). Three patients showed normalization of MARIAs score and showed no recurrence thereafter. None of the clinical variables collected showed significant association with recurrence, except for immediate postoperative advanced therapy which had a 70% protection from clinical recurrence [p=0.036 / HR 0.3 (0.097-0.92)]. Conclusion Long-term follow-up of CD patients undergoing SSIS showed that 57% of patients had clinical recurrence and 20% needed surgical reintervention. The MARIAs score was not predictive of long-term postoperative clinical or surgical recurrence as most features of the score remained unaltered. These shortcomings of the MARIAs score should be addressed when designing improved scoring tools.