The fate of cerebrospinal fluid after unrecognized incidental durotomy in cervical spine surgery.

Abstract

Cerebrospinal fluid (CSF) leakage due to incidental durotomy may not be recognized during cervical spine surgery. Thereafter large volume of CSF leakage may be found through inserted drainage. To examine the natural progress of large volume of CSF leakage after cervical spine surgery which were not managed by either revision surgery for dural repair or lumbar drainage. Retrospective cohort study. A total of 3,215 patients who underwent cervical spine surgery by a single surgeon between 2015 and 2022. The volume of the leaked CSF was measured on the T2 sagittal MRI using PACS volume measuring tool. Spontaneous absorption rate of CSF at 6-month postoperative period was calculated for each patient. For risk factor analysis, the incidence of unrecognized incidental durotomy was assessed according to types of surgery, revision surgery, presence of ligamentous ossification or smoking history. MRIs were taken in all 31 patients postoperatively and at 6 months follow up. The total incidence of unrecognized incidental durotomy was 1.09% (31/2949). Posterior laminectomy and fusion had 2.14%, followed by open-door laminoplasty (1.41%), and anterior surgery (0.34%). Revision surgery had significantly higher incidence of CSF leakage (4.67%) compared to primary cases (0.95%). Patients with ligamentous ossification showed higher incidence of CSF leakage (5.57%) compared to the patients without it (0.48%). The average spontaneous absorption rate was 95.0%. Leaked CSF was spontaneously absorbed within 6 months without any reoperation for dural repair or lumbar drainage. Risk factors for unrecognized incidental durotomy were posterior laminectomy and fusion, revision surgery, or existence of ligamentous ossification.