Surgical Success Rates

Source: Pediatr Neurosurg 1997 Apr 26:4 190-6

Within the first postoperative month, all patients or their parents reported clear improvement in their presenting symptoms and 93% were found to have clear improvement in their presenting signs. In follow-up periods of 6-70 months, all patients had continued unequivocal symptom improvement and all patients were found on examination to have clear improvement in neurological signs. In patients with syringomyelia, MRI studies carried out at least 6 months postoperatively revealed near total or total syrinx resolution in 80% of the cases. This study demonstrates that a standard bony and dural decompression of the foramen magnum region with modifications designed to maximize the restoration of CSF circulation across the foramen magnum is a safe, effective operative treatment for Chiari I malformation in children.

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The outcome following surgery for CM I is generally good. In 1989, Dyste, et al. presented the outcome in 50 patients with Chiari malformation, most having Chiari I. At follow-up, 20% were aysmptomatic, 66% were improved, 8% were stablized, and 6% showed progressive deterioration following surgical treatment. More recent studies show an improved outcome. The reports of Hida in 1995 and Klekamp in 1996 reveal 77% to 97% of patients remain symptom free at 3- to 5-year follow-up.

Some patients will continue to progress or have a recurrence despite treatment. The factors that have the greatest negative impact on outcome include the presence of muscle atrophy and symptom duration of over 2 years (Dyste 89). This argues for early treatment once symptoms develop.

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: Neurosurgery ; Volume 37,  Issue 6  1995 Dec  1069-74
Bindal AK, Dunsker SB, Tew JM Jr

In the 12 patients with syringomyelia, symptoms from brain stem compression dramatically improved with surgical decompression (P < 0.025), whereas symptoms from syringomyelia less dramatically improved or stabilized. The slight improvement or stabilization of syrinx symptoms represents a successful result, given the documented progressive nature of syringomyelia in this group. We conclude that surgical treatment for the Chiari I malformation can stabilize or slightly improve the symptoms attributed to syringomyelia and dramatically relieve the symptoms of brain stem compression. Furthermore, early diagnosis and treatment are critical in obtaining the best outcome for the patient.

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