Re-evaluation of foramen magnum decompression with dura left open for Chiari I malformation

One of the controversies in foramen magnum decompression (FMD) is the management of dura. Graft adhesion is the most common finding in revisions after FMD with duraplasty. Furthermore, certain number of patients after FMD without dural opening required revision surgery. The most common cause is excessive fibrosis over the preserved dura. On the other hand, FMD with dura left open could reduce the risk for symptomatic recurrence, although it was generally abandoned because of the higher risk of postoperative CSF leakage or meningitis. Purpose of this study was to re-evaluate FMD with dura left open after the application of tight fascial closures in order to reduce the risk of cerebrospinal fluid (CSF) leakage. We compared CSF-related complications of this surgery with other FMD techniques based on literature review. Our retrospective study included 13 patients who underwent FMD with dura left open. We paid particular attention to prevent CSF leak by the tight suturing of fascial layers especially at both ends of each layer and keeping muscle attachments to inion intact. CSF-related complications and symptomatic recurrence were not observed. The postoperative CSF collection contained within the tightly closed fasciae became of limited size over several months. FMD with dura left open did not show higher rate of CSF leakage as compared to other FMD techniques. The tight closure of fascial layers is essential to minimalize CSF leakage in this surgery. Moreover, it has the advantage of reducing symptomatic recurrence over other FMD techniques. •Attention in the tight fascial closure is described when the dura left open.•FMD with dura left open holds the potential for reducing symptomatic recurrence.•FMD with dura left open does not have higher rate of CSF-related complications as compared to FMD with duraplasty.