Introduction: This study was conducted to evaluate our results of surgically treated patients for chiari malformation-I (CM-I) with and without syringomyelia.
Methods: The medical records of all the patients undergoing posterior fossa decompression (PFD) were analysed. Extradural decompression with thinning of the sclerotic tissue and splitting of outer dural layer was performed in patients without syringomyelia. Duraplasty was performed In patients with syringomyelia.
Results: 8 males and 34 females with a mean age of 33.8 years were included. The most common presenting symptoms were headache, and/or tingling and numbness. CM-I with syrinx presented in 5/41 patients. PFD without durotomy was performed in 29/41 patients. The mean duration of preoperative symptoms was significantly longer in duraplasty group (4.6 versus 1.7 years, P = 0.005, OR = 0.48, CI = 0.29–0.8). Complications was significantly associated with duraplasty (P=0.004, OR=0.5, CI=0.3–0.8) with longer duration of hospital stay (P = 0.03, OR = 2.7, CI = 1.1–6.8). Patients had an overall complication rate of 6/41(15%). The overall improvement rate was 36/41 (84%); 12% (5/41) were stable; and worsening of symptoms were evident in 5% (2/41). Unfavorable outcomes were associated with prior CM decompression (P = 0.04, OR = 14, CI = 1.06–184). One patient had a recurrence a year after the PFD with duraplasty.
Conclusions: This study reports the association of duraplasty with longer duration of hospital stay and higher complication rate. Surgical outcomes with extra-dural decompression of the posterior fossa are favorable in patients with CM-I without syringomyelia. Intradural intra-arachnoid decompression is favorable for patients with syringomyelia and history of prior PFD. Hence duraplasty is not necessary except in certain conditions, in particular syringomyelia.
Patient Care: Further studies are required to provide more recommendation on the indication of intra or extradural decompression.
Learning Objectives: 1. In symptomatic CM patients without syringomyelia, the extra-dural dura- splitting decompression demonstrated a favorable outcomes.
2. Complications and longer duration of hospital stay was associated with duraplasty.
3. Intradural intra-arachnoid decompression is favorable in patients with syringomyelia and history of prior PFD.