The comparative analysis of MRI data in the early period after lumbar microdiscectomies with epidural injection of polyacrylamide hydrogel

Abstract

Objective: To perform a comparative analysis of MRI data obtained in the early postoperative period after repeated lumbar microdiscectomies in patients with and without epidural injection of “Nubiplant” polyacrylamide hydrogel (HG). Material and methods: The MRI data of the lumbar spine in the early postoperative period after repeated removal of herniated disc (on the 3-15th day) in 84 (100%) patients were analyzed: 30 (35,7%) patients were injected intraoperatively epidurally with “Nubiplant” HG to prevent epidural fibrosis (main group (MG) and in 54 (64,3%) patients the HG was not injected (control group (CG). Results: Comparative analysis of MRI data on the 3-15th day after surgery showed that the frequency of epidural edema and hemorrhage signs within the postoperative area in the MG was significantly lower as compared to the CG (p = 0,0444 and p = 0,0288 respectively). To assess the accuracy of the epidural administration of an artificial biopolymer Nubiplant during lumbar microdiscectomy, in the early postoperative period the following MRI criteria could be helpful: i) absence of the dural sac deformation and dislocations of the spinal root; ii) well-defined margin of the adjacent spinal root; iii) homogeneous MRI signals of the Nubiplant zone; iv) absence of Nubiplant areas outside the postoperative area; v) sufficient sectoral coverage of the adjacent root with epidurally administered Nubiplant (optimally >1800). Nubiplant” HG in the patients of the MG was evaluated, and MRI criteria for assessing the correctness of its introduction were proposed. Conclusions: In the early period after repeated lumbar microdiscectomies (on the 3-15th day), intraoperative epidural injection of “Nubiplant” HG was accompanied by a significant decrease of epidural edema and hemorrhage signs within the postoperative area. The proposed criteria of correctness of HG “Nubiplant” introduction allow unifying the approaches in radiological assessment of this patients.