Imaged-guided and muscle sparing laparoscopic anorectoplasty using real-time magnetic resonance imaging

A challenge when repairing imperforate anus is positioning the neo-rectum into the center of the sphincter muscle complex (SMC) with limited muscle injury and scarring. Unfortunately, the path through the components of the SMC are often non-linear. We have used MRI to delineate the complex and guide the needle through the center using standard MRI-guidance (Raschbaum GR et al. J Pediatr Surg 45:220-223, 2010; Thomas TT et al. J Pediatr Surg 35:927-930, 2000). However, asynchronous scanning requires multiple, time-consuming scans to advance the needle in stepwise fashion. Asynchronous scanning also prevents visualizing the needle as it is advanced. We recently integrated software into the MRI operative suite that allows placement of the needle with real-time MRI. We report the feasibility and utility of real-time MRI-assisted laparoscopic assisted anorectoplasty (RT MRI-LAARP). Needle guidance was performed with Siemens Espree 1.5 T MRI with T1 Flash RT Sequence. After needle placement, laparoscopic mobilization, fistula takedown and pull-through was performed using the needle to guide dilation to create a tract to pull-through the neo-rectum. Charts of patients who underwent RT MRI-LAARP were reviewed. Demographics, anatomy, number of needle passes, OR duration and complications are reported. There were five children that underwent RT MRI-LAARP; one was a redo secondary to a retracted rectovestibular fistula. Operative time ranged from 187-505 min. Average hospital stay was 4.0 ± 1.0 days. There were no intraoperative complications although one patient had temporary urinary retention post-op. Muscle sparring laparoscopic anorectoplasty using real-time MRI is feasible and facilitates needle placement through the SMC.