Endoscopic Suboccipital Decompression on Pediatric Chiari Type I

Abstract

Object: To minimize the invasiveness and maximize the adequacy of Chiari decompression on pediatric patients, 0° and 30° endoscopes were adapted to perform the procedure of suboccipital craniectomy and upper cervical laminectomies.

Methods: Via a 2-cm midline skin incision, craniectomy and C1 laminectomies were performed by using 0° and 30° lens endoscopes. From October 2003 to December 2006, twenty-six pediatric patients underwent the endoscopic procedure; 16 were male and 10 female, whose ages ranged from 18 months to 16 years (mean±SD: 8.07±4.45 years).

Results: Ten of the 26 patients experienced suboccipital headache and cervical pain, 11 presented with dysphagia, choking, frequent nausea/gaging and vomiting, 6 presented with development delay in fine motor function and speech, 5 experienced ataxia, 6 with synrinx, 4 with hydrocephalus, 1 with pseudotumor cerebri and other symptoms including diplopia, weakness and numbness in extremities, nystagmus, and sleep apnea. Intraoperative monitoring of somatosensory evoked potentials (SSEPs) was used for the procedures in 11 patients. The follow-up period ranged from 4 to 39 months (mean±SD: 20.69±10.10 months). Postoperative improvement including complete and partial resolution of preoperative symptoms was shown in 92.3% of patients. Two cases have gained no improvement and one experienced postoperative complications – bacterial meningitis – which was successfully controlled with antibiotics. No mortality, cerebrospinal fluid (CSF) leak, pseudomeningocele, cerebellar ptosis and postoperative hydrocephalus were seen in this series. The average length of hospital stay was 2 nights.

Conclusions: The use of the endoscope through a suboccipital craniectomy and upper cervical laminectomies has made Chiari decompression in pediatric population comparable with the conventional procedure in terms of minimal surgical invasiveness, recovery time, and complexity of the procedure.

Key words

endoscopy - Chiari malformation - suboccipital craniectomy - craniovertebral junction - cervicomedullary junction

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