Notable differences in changes between ventral and dorsolateral spinal longitudinal extradural CSF collection after treatment in patients with spontaneous spinal CSF leaks.

Spontaneous spinal CSF leaks can lead to significant clinical symptoms and present a diagnostic challenge. However, the relationship between post-treatment headache relief and changes in epidural CSF collections, commonly observed laterally and dorsally around the dural sac, or in ventral spinal longitudinal extradural CSF collections (vSLEC), is not yet well understood. Forty-five consecutive patients with spontaneous CSF leaks (female, 28; median age, 44 years) treated at our hospital between April 2006 and December 2023 were retrospectively investigated. Clinical outcomes were assessed in all 45 patients following treatment, which included conservative management with intravenous fluids and rest (7 cases [15.6%]), and large-volume epidural blood patch (38 cases [84.4%]), including an analysis of changes in dorsolateral epidural CSF collection and vSLEC at baseline and final follow-up in 35 patients who underwent postoperative MRI. The findings of dorsolateral epidural CSF collection disappeared or reduced after treatments in all 35 patients (disappearance, 20 of 35 cases [57.1%]; marked reduction, 13 [37.1%]; and mild reduction, 2 [5.7%]). Conversely, post-treatment MRI was available in 32 (77.3%) of 41 patients with vSLEC findings at baseline (median follow-up period, 129 days). The changes in vSLEC were as follows: disappearance, 4 of 32 cases (12.5%); marked reduction, 10 (31.3%); mild reduction, 12 (37.5%); no change, 4 (12.5%); and enlargement, 2 (6.2%). In conclusion, despite the low rate of vSLEC reduction after treatment, patients experienced significant headache relief in 44 (97.8%) of the 45 cases, along with a high rate of reduction in dorsolateral epidural CSF collections following treatment. Clinical trial number: not applicable.