Minimally Invasive Technique for Chiari I Decompression Without Durotomy: Surgical Technique and Preliminary Case Series

Abstract

BackgroundChiari I malformation, marked by severe headaches and potential brainstem/spinal cord issues, often requires surgical intervention when conservative methods fail. This study introduces a minimally invasive surgery (MIS) Chiari decompression technique utilizing a 3-blade retractor, aiming to reduce post-operative discomfort and optimize outcomes. MethodsChiari type 1 malformation patients who underwent a MIS technique were included. Technique consisted of a minimal- soft tissue opening using a 3-blade retractor, suboccipital craniectomy, C1 laminectomy, and resection of the atlantooccipital band without a durotomy. Results10 patients were treated. Mean age was 43.3 years with 7 females. All patients presented occipital headaches, 50% retroorbital pain, 40% neck, upper back or shoulder pain, and 30% limb paresthesias. Median pre-surgical modified Rankin Scale (mRS) was 3 (2-4) and pain visual analog score (VAS) was 7 (5-9). Mean operative time was 59 (59-71) min, with mean blood loss of 88.5 (50-140) mL. 90% of patients were discharged the same surgical day (mean 7.2 [5.3-7.7] hours post-op). No immediate or delayed post-operative complications were evidenced. At 6-months, 90% of patients had mRS 0-1. At last follow-up the VAS mean was 1.5 (range 0-4, p<0.001). ConclusionThe MIS 3-blade flexible retractor technique for Chiari decompression is feasible, provides wide visualization angles of the suboccipital region and C1 arch, allows 2-surgeon work, and minimizes skin and soft tissue disruption. This combination may diminish post-operative discomfort, reduce the risk of surgical site infections, and optimize outcomes.