There is a risk of requiring a permanent VP shunt associated with decompression for Chiari I even in the absence of ventriculomegaly or signs of raised ICP pre-operatively. Patients presenting with new symptoms or CSF wound leak following FMD mandate investigation to exclude hydrocephalus, raised ICP or subdural hygroma.

In this paper authors present two cases of multiple schwannomas without the features of neurofibromatosis (NF). The authors retrospectively reviewed the hospital charts, radiology films, operative notes and pathology slides of these two patients. There was no family history of neurofibromatosis. The two patients had contrast enhanced MRI, which was negative for vestibular schwannomas. Both underwent surgical excision of symptomatic lesions. Histopathology confirmed these lesions as schwannomas. Molecular genetic analysis in case 1 demonstrated two distinct mutations of the NF2 gene in two different schwannomas, with concomitant loss of heterozygosity in both tumours. In contrast peripheral blood lymphocytes did not reveal mutations of NF2. The authors recommend surgery for symptomatic lesions. Asymptomatic tumours can be monitored. Regular follow up is essential as they may develop fresh lesions at any time. The relevant literature is discussed.

The natural history of Chiari malformation and our ability to alter it is poorly understood, and reported results of hindbrain decompression show high recurrence rates. We report 11 years of experience of hindbrain decompression, to evaluate long-term outcome related to surgical technique. The results of patients who underwent hindbrain decompression between 1994 and 2005 were retrospectively analysed. We identified 96 patients from operative records and reviewed all clinical records for presenting symptomatology and examination findings. Decompression technique includes traditional decompression, duraplasty and bone--only decompression. Symptoms at the last available follow-up visit were defined by the assessing clinician as resolved, improved, unchanged or worse. There were 35 males and 61 females with a mean age of 33 years (range 6 - 62 years). The mean length of follow-up is 3.6 years with a range of 6 months to 9 years. Postoperative resolution or improvement in symptoms was seen in 75 patients (78%). Drop attacks and headaches were the most likely to respond to hindbrain decompression, showing improvement or resolution in 100 and 92% of cases. Dysaesthetic arm pain and weakness carried the worse prognosis with only 20% having symptom resolution. Sixteen patients had only bony decompression leaving the dura intact. In eight patients (66%) the headaches resolved following bony decompression alone. However the headaches were unchanged in 25% of cases. Dysaesthetic pain and weakness was unchanged in 60%. Restoration of CSF flow dynamics at the foramen magnum by surgical decompression does not consistently result in resolution of symptoms in all patients. Identification of predictors of successful outcome following decompression, coupled with early intervention and appropriate choice of procedure may result in improved outcomes. Although this is a retrospective study it suggests that bone only decompression should be reserved for patients with isolated headache.

Purpose Predictive models in spine surgery are of use in shared decision-making. This study sought to develop multivariable models to predict the probability of general and surgical perioperative complications of spinal surgery for lumbar degenerative diseases. Methods Data came from EUROSPINE's Spine Tango Registry (1.2012–12.2017). Separate prediction models were built for surgical and general complications. Potential predictors included age, gender, previous spine surgery, additional pathology, BMI, smoking status, morbidity, prophylaxis, technology used, and the modified Mirza invasiveness index score. Complete case multiple logistic regression was used. Discrimination was assessed using area under the receiver operating characteristic curve (AUC) with 95% confidence intervals (CI). Plots were used to assess the calibration of the models. Results Overall, 23′714/68′111 patients (54.6%) were available for complete case analysis: 763 (3.2%) had a general complication, with ASA score being strongly predictive (ASA-2 OR 1.6, 95% CI 1.20–2.12; ASA-3 OR 2.98, 95% CI 2.19–4.07; ASA-4 OR 5.62, 95% CI 3.04–10.41), while 2534 (10.7%) had a surgical complication, with previous surgery at the same level being an important predictor (OR 1.9, 95%CI 1.71–2.12). Respectively, model AUCs were 0.74 (95% CI, 0.72–0.76) and 0.64 (95% CI, 0.62–0.65), and calibration was good up to predicted probabilities of 0.30 and 0.25, respectively. Conclusion We developed two models to predict complications associated with spinal surgery. Surgical complications were predicted with less discriminative ability than general complications. Reoperation at the same level was strongly predictive of surgical complications and a higher ASA score, of general complications. A web-based prediction tool was developed at https://sst.webauthor.com/go/fx/run.cfm?fx=SSTCalculator.

No abstract