The value of postoperative MR in tethered cord: A review of 140 cases

Purpose: This study aimed to determine the justification for routine postoperative MRI (POMR) following surgical release of tethered cord (TC) given that an MR, in this situation, mostly serves as a baseline and rarely has immediate clinical implications. Furthermore, later in the course of the disease, the presence of retethering is mostly assessed by clinical parameters, rather than imaging. Methods: A single-center retrospective review of patients who underwent tethered cord release surgery between the years 1997 and 2009 at the Department of Pediatric Neurosurgery, Tel Aviv Medical Center, Israel was performed. Collected data including basis for diagnosis, pathology, associated clinical and radiologic findings, surgical procedure and outcome, postoperative follow-up and morbidities, and postoperative MRI findings were recorded and analyzed. Results: One hundred forty patients operated upon between 1997 and 2009 for tethered cord syndrome were reviewed. Routine postoperative MR was performed in all cases 6-18 months after surgery. All cases were fully untethered. MR revealed relevant information in eight cases, two with residual dermoid, and six with significant terminal syrinx. None of these findings led to repeat surgery or special treatment. Retethering operations were performed in two cases in which retethering was diagnosed based on clinical evaluation. Conclusions: Based on analysis of our series of 140 consecutive patients who all underwent POMR 6-18 months after TC release, we suggest that POMR as routine clinical practice is not justified for uncomplicated cases of TC release. In cases of high risk for retethering, or significant preoperative syrinx or dermoid, POMR is recommended to establish a baseline for future clinical follow-up.