A Combinatorial Approach with Cerebellar Tonsil Suspension to Treating Symptomatic Chiari Malformation Type I in Adults: A Retrospective Study

World Neurosurg. 2020 Nov:143:e19-e35. doi: 10.1016/j.wneu.2020.02.184. Epub 2020 Mar 12.

Abstract

Background: Primary Chiari malformations (CMs) are congenital defects of the skull base and brain. Among the 4 CM types, type I (CM-I) occurs most frequently and may cause somatosensorimotor, autonomic and vision symptoms. Presently, posterior fossa decompression alone (PFD) or with duraplasty (PFDD) and cerebellar tonsil (CbT) shrinkage tactics are standard treatments, albeit inherent issues. There has been no report on devising CbT suspension (CTS) to manage CM-I.

Objectives: 1) To design a CTS protocol that can be used with CbT coagulation (CTC) and PFDD; 2) to evaluate the regimen for feasibility, safety, and efficacy in a retrospective study; and 3) to obtain data for planning prospective studies to validate PFDD + CTC + CTS as a novel approach to treating adult CM-I.

Methods: PFDD + CTC + CTS (n = 17), PFDD + CTC (n = 13), and PFDD (n = 12) were performed for 42 adult patients (age range, 18-55 years; female:male = 27:15) following a balanced study design. Neck Disability Index (NDI), Chicago Chiari Outcome Scale (CCOS), and /magnetic resonance imaging/computed tomography were used to determine postsurgery outcomes for approximately 20 months.

Results: Comparing to PFDD + CTC or PFDD, patients receiving PFDD + CTC +CTS operation exhibited significantly improved group average NDI (10.72 ± 3.95%; P = 0.007), CbT elevation distance (7.06 ± 2.42 mm; P < 0.001, Kruskal-Wallis test; 55.7 ± 25.4% higher than the presurgery level; P < 0.001, analysis of variance), and syringomyelia syrinx retraction (P = 0.009, analysis of variance).

Conclusions: The PFDD + CTC + CTS regimen appeared to be safe and potentially more efficacious in patients with CM-I evaluated for the period, relative to PFDD + CTC or PFDD treatment. Future prospective studies were warranted.

Keywords: Cerebellar tonsil coagulation; Cerebellar tonsil suspension; Chiari malformation type I; Chicago Chiari Outcome Scale; Duraplasty; Neck Disability Index; Syringomyelia.

MeSH terms

  • Adolescent
  • Adult
  • Arnold-Chiari Malformation / physiopathology
  • Arnold-Chiari Malformation / surgery*
  • Cerebellum / surgery*
  • Cervical Atlas / surgery
  • Decompressive Craniectomy / methods*
  • Dura Mater / surgery
  • Female
  • Humans
  • Laminectomy / methods
  • Male
  • Middle Aged
  • Occipital Bone / surgery
  • Plastic Surgery Procedures / methods*
  • Retrospective Studies
  • Suture Techniques*
  • Syringomyelia / physiopathology
  • Syringomyelia / surgery
  • Young Adult

Supplementary concepts

  • Chiari Malformation Type I with Syringomyelia