Headache Relief Stratified by Location for Pediatric Patients Undergoing Posterior Fossa Decompression for Chiari-1 Malformation With Syringomyelia

Introduction: Patients with Chiari-1 malformation (CM) often present with occipital/suboccipital headaches. However, patients may also present with atypical headache patterns or locations. We evaluated the impact of posterior fossa decompression on typical versus atypical headaches in pediatric patients with Chiari-1 malformation with syringomyelia (SM).

Methods: We utilized the Park-Reeves Syringomyelia Research Consortium database to identify pediatric patients with CM+SM who received posterior fossa decompression with (PFDD) or without (PFD) duraplasty with ≥1 year of follow-up data. Preoperative headache characteristics, including location, and postoperative improvements in headaches and syringes were compared between groups.

Results: 349 patients were analyzed (mean age 11.2 years, mean follow-up 2.6 years). One-hundred sixty-four patients (41.5%) had occipital/suboccipital, 115 (23.1%) had holocranial, 81 (20.5%) had frontal, 20 (5.1%) had temporal, and 15 (3.8%) had parietal headaches. Seventy-eight (22.3%) patients had Valsalva-induced headaches; 59 (16.9%) had headaches with nausea/vomiting. PFDD was performed for 283 patients (81.1%). Valsalva-induced headaches were more associated with suboccipital headaches (60.2%) compared to holocranial (17.9%), frontal (14.1%), temporal (5.1%), or parietal (2.6%) headaches (p=0.005). Suboccipital headaches more often improved postoperatively (86.6%) compared to holocranial (79.1%), frontal (65.4%), temporal (55.0%), or parietal (46.7%) headaches (p < 0.001 in a priori and post-hoc analyses). Improvements in Valsalva-induced headaches did not differ by headache location. Between PFD and PFDD, there were no differences in postoperative headache improvement by headache location or for Valsalva-induced headaches. PFDD was utilized more for patients with holocranial (p=0.01), frontal (p < 0.001), and temporal (0.003) headaches. Preoperative syrinx diameter and postoperative change in diameter were not associated with headaches. Preoperative syrinx length, but not postoperative change in length, was negatively associated with headaches (p=0.002; OR: 0.94).

Conclusion : Patients with typical Chiari headaches more often symptomatically benefitted from PFD/PFDD than those with atypical headaches. PFDD and PFD provided equivalent headache relief. Change in SM was not associated with headaches.