Obesity and posterior spinal fat content: impact on complications in non-complex lumbar spine surgery.

AIM: Obesity is increasing in prevalence across the world with a potentially very significant impact in spine surgery. This study aimed to characterise this in the setting of neurosurgical spine practise at a single centre in UK. Uniquely, we assess the contribution of posterior spinal fat content to intraoperative complications. MATERIALS AND METHODS: All cases of lumbar spine surgery in 1 year were investigated. Case note review was carried out documenting patient demographics, comorbidities, operative details, complications and length of stay. Ninety-four complete datasets were compiled from 128 cases. The posterior spinal fat content was recorded from T2-weighted MRI. Body mass index (BMI) was correlated with each measure using logistic multiple regression and contingency table analysis. RESULTS: Mean BMI was 28.3 (SD: 5.2) comprising one underweight (BMI <18.5), 26 normal weight (BMI: 18.5-24.9), 32 overweight (BMI ≥25), 33 obese (BMI ≥30) and two morbidly obese patients (BMI ≥40). BMI (coefficient: 0.03, SE: 0.01, p = 0.005) and posterior spinal fat content (coefficient: 0.01, SE: 0.005, p = 0.042) correlated significantly with increasing length of stay. Procedure (p = 0.006) and complication rate (p = 0.010) also correlated with length of stay. Neither BMI nor posterior spinal fat content had a significant effect on the incidence of perioperative complications (p = 0.932, p = 0.742), operating time (p = 0.454, p = 0.748) or blood loss (p = 0.127, p = 0.692). There were three non-operative complications in the obese and overweight groups compared with none in the normal weight group, but this was not significant. Overall complication rate was 15%. CONCLUSION: Obesity and posterior spinal fat content correlate with the length of stay in simple spine surgery. There is a non-significant trend towards increased non-operative complications in overweight and obese patients, which could reach significance with larger numbers and prospective data. Excess posterior spinal fat is not associated with increased operative complications, operating time or blood loss.

A 5-year retrospective study assessing the association between seasonal and meteorological change and incidence of aneurysmal subarachnoid haemorrhage.

OBJECTIVE: Seasonal variation in incidence of spontaneous subarachnoid haemorrhage (SAH) is well recognised. This retrospective single-centre study aimed to characterise seasonality of SAH in the temperate climate of London, UK and to determine associations of incidence with meteorological variables. We further investigated whether associations vary according to location of aneurysm. METHODS: Admission data on 647 patients admitted with spontaneous SAH from December 2003 to August 2008 was analysed using our neurosurgical referrals database. Average monthly incidence of SAH was correlated with local temperature, atmospheric pressure and humidity data. In a subset of 467 patients, impact of aneurysm location on seasonal variation was evaluated. RESULTS: A non-significant bi-annual peak incidence was observed in Spring and Autumn with a trough in Summer (chi(2) = 1.5, p = 0.47). This trend was particularly marked with middle cerebral and posterior communicating artery aneurysms. However, anterior communicating artery aneurysmal SAH peaked in Summer only. SAH incidence correlated significantly with average humidity (coefficient 0.213, CI (0.02-0.404), p = 0.035) and peak humidity (coefficient 0.128, CI (0.008-0.248), p = 0.041). Temperature and atmospheric pressure did not correlate with incidence. CONCLUSIONS: This study illustrates a pattern of variation in SAH incidence similar to that seen in other populations and climates. However, our data suggests that this pattern differs according to aneurysm location. Unusually, we also find that humidity, and not temperature or atmospheric pressure, correlates with SAH incidence. Seasonal variability in aneurysm rupture is likely to be multifactorial, but meteorological factors may play an important role.

Coma caused by spontaneous otogenic pneumocephalus.

We present the first case of spontaneous otogenic pneumocephalus presenting with a rapid deterioration in conscious level. This occurred in a 69-year-old woman who was subsequently treated with a subtemporal, extradural exploration and packing of the multiple defects in the mastoid air cells. The patient made a full neurological recovery within 10 weeks. Spontaneous otogenic pneumocephalus is a rare condition and was previously understood to present with subtle symptoms of headache, aphasia and cognitive deficits. This case, however, establishes how it can cause a rapid decline towards coma.

Tumour resection volumes and facial nerve outcomes for vestibular schwannomas.

The objective of this study is to correlate tumour volume relationship with surgical outcomes in subtotal resections and accepted nomenclature through a retrospective study at Charing Cross Hospital, London, a tertiary referral centre. The participants were 16 patients with vestibular schwannoma managed with subtotal resection between 2002 and 2011. The main outcome measures were surgical technique; tumour volume; recurrence and post-operative facial nerve function. Mean pre-operative and post-operative volumes for all patients were 14.7 and 3.7 cm(3) respectively. Tumour volumes do not correlate with diameter (p < 0.05). Mean reduction in volume of these subtotal resections was 75 %. Long term facial nerve outcome was good in the majority of patients: House-Brackmann Grade I/II in 12 (75 %), Grade III/IV in 2 (12.5 %) and Grade V/VI in 2 patients (12.5 %). Notably, two patients with Grade I/II House-Brackmann grading later developed Grade V/VI palsy following adjunctive radiotherapy. Seven of the 16 subtotal resections had subsequent radiotherapy or microsurgery. Mean follow up was 26.5 months. In conclusion, subtotal resections lead to good facial nerve outcomes but may require further treatments. Radiation treatment can worsen facial nerve function. There is no standardised use of tumour volumes or accepted guidelines for resection terminology. We propose the use of tumour volumes to define this further.