Purpose: Foramen magnum decompression is a common surgical treatment for Chiari type 1 malformation (CM-1). There are several methods for the intervention to the dura matter such as dural plasty sectioning the dura, also removing the outer membrane of the dura without intradural manipulation. We compared retrospectively our cases with a presentation of illustrative cases. Finally, we add our comments to the worldwide questionnaire which was offered.
Methods: Twenty-six patients (9 males and 17 females) who underwent surgery from 2010 to 2019 were included. The age distribution was 1 to 55 years old (mean: 16.4 ± 11.3).They were divided into two groups, group A which underwent outer membranectomy and group B which underwent dural plasty.
Results: There were 15 cases in group A and 11 cases in group B, and tonsillectomy was performed in 5 cases out of the 11. Symptoms improved in 7 cases (47%) and 5 cases (45%), respectively. Improvement of the syrinx was seen in 14 cases (93%) and 10 cases (90.9%), respectively. No complications were seen in group A; however, one CSF leak and 2 pseudomeningoceles were seen in group B.
Conclusion: The number of our cohort is not large enough to analyze statistics, but it seems that outer membranectomy is similar to dural plasty in terms of the results of surgery with a lower risk of complications for the treatment in non-complicated CM-1.
Keywords: Chari type 1 malformation; Outermenbrenectomy; Surgical indication.