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.

Intracranial thrombosis after ventriculoperitoneal shunting.

We report a case of intracranial thrombosis (IT) after ventriculoperitoneal shunting (VPS). We reviewed the literature to highlight the importance of considering the possibility of cerebral venous thrombosis following VPS, even though it is a rarely reported complication. A 14-year-old boy underwent distal catheter replacement due to its short size that was detected during a routine consultation. Five days postoperatively, he experienced nausea, vomiting, seizures, and headache. Although a diagnosis of meningitis was considered, diagnosis of IT was eventually confirmed through computed tomography venography and gadolinium magnetic angioresonance. The patient subsequently underwent anticoagulant therapy, which led to complete resolution of symptoms. In this report, we suggest a possible association between VPS and IT, which is a complication that is not commonly reported. The literature suggests that decreased blood flow due to over-drainage of CSF after VPS causes decreased head pressure, culminating in venous stasis and consequent thrombosis. In addition, the literature describes associations between IT and lumbar puncture (LP); therefore, it is important to consider the possibility of IT following these procedures.