The impact of neurosurgical technique on the short- and long-term outcomes of adult patients with Chiari I malformation

Abstract

ObjectiveThis study is aimed to compare and evaluate any differences in clinical and radiological outcomes of different operative techniques of cranio-cervical decompression (CCD) performed in adults with symptomatic Chiari malformation type I (CM-1) within a single tertiary neurosurgical center. MethodsA retrospective review using the Hospital theatre management system (ORSOS) and records of patients who underwent CCD for CM-1 between January 2011 and October 2019 was performed.Patients were divided in three cohorts according to the operative technique used: an extradural osteo-ligamentous decompression (BD), BD followed by dural opening either without duraplasty (DOWD) or plus duroplasty (DOPD). The primary clinical outcome was measured by utilizing the Chicago Chiari Outcome Scale (CCOS). Syrinx outcome was measured on post-op MRI. Statistical analysis was performed using IBM SPSS 24 with α = 0.05. Results67 adults underwent 69 CCD: 10 BD, 29 DOWD and 30 DOPD. Median follow-up was 47.3 months (Interquartile Range (IQR) 26.3–73.7). Patients who underwent DOPD had a shorter median hospital stay (p-value 0.001), fewer unplanned readmissions (p-value 0.015), a higher median CCOS (p-value 0.001) and a lower post-operative complications rate (p-value 0.001) compared to patients who underwent DOWD. BD revealed a 40 % failure rate and was ineffective in cases with syringomyelia. ConclusionBetter clinical outcomes, lower complication risk, and short duration of hospital stay were associated with patients who underwent dural opening with augmentative watertight duraplasty. Bony decompression alone despite being a very safe technique, does not appear to be reliable and effective in controlling and relieving the clinical symptoms and the syringomyelia of adult patients with CM-1.