The Chiari II malformation: a surgical series

Surgical management of Chiari II malformation: a systematic review of literature

PURPOSE

Chiari II malformation (CM-II) is a congenital malformation of the posterior fossa associated with myelomeningocele. Of the symptomatic patients, 10-33% require surgical treatment. To this date, there is not a consensus about the best surgical technique, and whether to do duroplasty.

METHODS

A literature search of the PubMed database and crossed references was performed, per PRISMA guidelines. Data regarding demographic features, extent of cervicomedullary deformity, clinical presentation, surgical techniques, and clinical outcomes were extracted. Pearson's chi-squared test was applied. The p-values under 0.05 were considered statistically significant.

RESULTS

Twenty studies (N = 330) were analyzed. C3 and C4 levels represented 56.4% of the lowest tonsil displacement. The most reported symptom was dysphagia/swallowing dysfunction (53.8%). Suboccipital craniectomy (SOC) and cervical spine expansion (CSE) with duroplasty were the most reported technique. Dural augmentation was performed in 57.4% of the patients. After surgery, 59.6% observed an improvement in symptoms and quality of life, 12.5% were unchanged, and 27.8% had a worsened clinical status. The mortality rate was 2.5% during the first month after surgery, and 17.4% at the last follow-up evaluation. Patients who underwent CSE presented a better clinical outcome (p = 0.002). The SOC procedure could not be correlated with symptom improvement (p = 0.06).

CONCLUSION

CM-II is associated with high morbidity and mortality. An early onset symptomatic CM-II demands intervention, which provided an improvement of outcome in most patients included in this review. The best surgical technique and the exact effect of the surgical management of CM-II on mortality are not yet clear.

Dural sac restenosis due to regeneration of the resected C1 lamina in a patient with Chiari malformation: a case report and literature review

Although foramen magnum decompression (FMD) is effective for the treatment of Chiari malformation type I (CM1), reoperations may be required in cases of insufficient decompression. We encountered a patient who experienced restenosis due to regeneration of resected C1 laminae and required reoperation after FMD.We present the case of a 14-year-old boy with symptomatic CM1 and syringomyelia who underwent FMD with outer dura layer incision and C1 laminectomy. He experienced gait disturbance, hyperesthesia, and hyperhidrosis, which did not improve after the surgery. He experienced recurrence of the stenosis at the age of 16 years, for which he underwent resection of the regenerated C1 arch and duraplasty. His symptoms gradually resolved after the second surgery.The recurrence might have been caused by regeneration of the C1 laminae. Bone regeneration rarely necessitates reoperation. Frequent follow-up is important after decompression surgery for Chiari malformation in young patients.

Who needs surgery for pediatric myelomeningocele? A retrospective study and literature review

INTRODUCTION

Children with myelomeningocele (MMC) are usually subjected to multiple surgeries. However, the number and type of surgeries are not the same in every patient with MMC over time. This report summarizes the surgical interventions in a cohort of several ages.

MATERIALS AND METHODS

Data on all of the patients with MMC, aged from 1 year and 10 months to 21 years and 11 months, were retrospectively reviewed at the Dona Estefânia Hospital in Lisbon, Portugal. Data were collected by chart review and individual interviews. The factors analyzed were demographics, ambulatory status, neurological level of involvement, shunt status, Arnold-Chiari malformation type II, surgical history, and occurrence of fracture. The surgical interventions were categorized as neurosurgical, orthopedic, urinary, ulcer repair and others.

RESULTS

A total of 84 alive were eligible and enrolled. The average age was 14 years and six months. A total of 59 patients received shunts (all but one ventriculoperitoneal). In the study group, the 84 patients required 663 surgeries. Neurosurgical interventions were the most frequent surgical procedure and predominated during the first 2 years of life. Surgical interventions related to shunts were the most common neurosurgical interventions. Orthopedic surgeries were more frequent in the age group 6-12 years. Urological surgeries were done mainly after 6 years of age. Surgical repair of pressure ulcers was more common after 12 years of age.

CONCLUSIONS

Our study brings to light the complexity of this condition, with multiple surgeries among patients with MMC.

Revision surgery for chiari malformation decompression

Chiari malformations comprise four different hindbrain anomalies originally described by Hans Chiari, a professor of pathology at the German University in Prague. There are four basic Chiari malformations. The reasons for revision of Chiari malformation decompression may be for conservative or inadequate initial decompression or the development of postoperative complications. Another reason involves cases of both hindbrain herniation and syringomyelia in patients who have undergone adequate posterior fossa decompression without resolution of symptoms, signs, or radiological appearance of their syrinx cavity. Additionally, symptom recurrence has been reported in association with various types of dural grafts. Reoperation or revision surgery for patients with Chiari malformations is common and may not be due to technical error or inadequate decompression. The types of revision surgeries, their indications, and initial presentations will be reviewed.