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

BACKGROUND CONTEXT: 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.

PURPOSE: 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.

STUDY

DESIGN

Retrospective cohort study.

PATIENT SAMPLE: A total of 3,215 patients who underwent cervical spine surgery by a single surgeon between 2015 and 2022.

OUTCOME MEASURES: 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.

METHODS

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.

RESULTS

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%.

CONCLUSION

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.