The utility of the CADISS® system in the dissection of epidural fibrosis in revision lumbar spine surgery (A case series)

Spine surgery and spinal fusion surgery are rising. Revision rates following initial surgery are between 8 and 45%. Epidural fibrosis is a common response to spine surgery for most patients and increases complications in revision surgery. Previous research suggests using MESNA (Sodium 2-mercaptoethane sulfonate) in combination with mechanical blunt dissection safely reduces surgical complications. MESNA is a mucolytic agent which selectively cleaves disulphide bonds involved in the adherence and strength of fibrosis, meaning cutting in-struments are not needed. The Chemically Assisted DISSection (CADISS (R)) System is an optimised non-cutting surgical device, consisting of a reconstitution cartridge for MESNA preparation, irrigated surgical instruments, and a footswitch to control MESNA release. This is the first study to investigate the use of the CADISS (R) System in revision spine surgery.Methods: This was a prospective, open label, observational case study. We enrolled 21 patients for revision spine surgery with the CADISS (R) System at two Belgium sites. The primary assessment was the number of successful removals of epidural fibrosis without cutting. The amount of MESNA used, total dissection and procedure time were recorded. For secondary criterion, the surgeons assessed global satisfaction, facilitation of dissection, quickness of action, usability, bleeding reduction and visualisation of the cleavage plane using an 11-point Likert scale (0-10). Due to the exploratory nature, no formal statistical analysis was planned. We calculated the per-centage and confidence interval of successful procedures, the medians and corresponding interquartile range of the Likert criterion, and the mean (+/- SD) of the amount of MESNA used, CADISS (R) dissection time and total procedure time.Results: 24 fibrosis dissections were performed in 19 patients and 23 were successful (95.8%, CI: 78.9%; 99.9%). The mean amount of MESNA used, mean dissection time and procedure time were 16 ml (+/- 4.94), 16.5 min (+/- 16.1) and 86.3 min (+/- 25.1), respectively. No dural tears were reported. The mean global satisfaction score was 9.0 (8.0-9.0). All other Likert criterion had scores of 8.0 or 9.0, excluding quickness of action, which scored 7.0 (6.0-9.0).Conclusions: The CADISS (R) System in revision spine surgery has potential to effectively reduce dissection complications.