Surface-based tracking for short association fibre tractography.

It is estimated that in the human brain, short association fibres (SAF) represent more than half of the total white matter volume and their involvement has been implicated in a range of neurological and psychiatric conditions. This population of fibres, however, remains relatively understudied in the neuroimaging literature. Some of the challenges pertinent to the mapping of SAF include their variable anatomical course and proximity to the cortical mantle, leading to partial volume effects and potentially affecting streamline trajectory estimation. This work considers the impact of seeding and filtering strategies and choice of scanner, acquisition, data resampling to propose a whole-brain, surface-based short (≤30-40 mm) SAF tractography approach. The framework is shown to produce longer streamlines with a predilection for connecting gyri as well as high cortical coverage. We further demonstrate that certain areas of subcortical white matter become disproportionally underrepresented in diffusion-weighted MRI data with lower angular and spatial resolution and weaker diffusion weighting; however, collecting data with stronger gradients than are usually available clinically has minimal impact, making our framework translatable to data collected on commonly available hardware. Finally, the tractograms are examined using voxel- and surface-based measures of consistency, demonstrating moderate reliability, low repeatability and high between-subject variability, urging caution when streamline count-based analyses of SAF are performed.

Detecting microstructural deviations in individuals with deep diffusion MRI tractometry.

Most diffusion magnetic resonance imaging studies of disease rely on statistical comparisons between large groups of patients and healthy participants to infer altered tissue states in the brain; however, clinical heterogeneity can greatly challenge their discriminative power. There is currently an unmet need to move away from the current approach of group-wise comparisons to methods with the sensitivity to detect altered tissue states at the individual level. This would ultimately enable the early detection and interpretation of microstructural abnormalities in individual patients, an important step towards personalized medicine in translational imaging. To this end, Detect was developed to advance diffusion magnetic resonance imaging tractometry towards single-patient analysis. By operating on the manifold of white-matter pathways and learning normative microstructural features, our framework captures idiosyncrasies in patterns along white-matter pathways. Our approach paves the way from traditional group-based comparisons to true personalized radiology, taking microstructural imaging from the bench to the bedside.

Effect of Steroid Therapy on Risk of Subsequent Surgery for Neurologically Stable Chronic Subdural Hemorrhage-Retrospective Cohort Study and Literature Review.

BACKGROUND: Chronic subdural hemorrhage (CSDH) is a common neurosurgical pathology. While acute deterioration is managed surgically, the optimal management of patients with neurologically stable CSDH remains uncertain. Despite an increasing interest in the use of corticosteroids, it is unclear whether this reduces the rate of subsequent crossover to surgery. In this study we evaluate rate of crossover to surgery in such patients managed in our Neurosurgical unit. METHODS: A retrospective database search over a 2-year period was performed. A multi-database literature review was also conducted to identify relevant articles reporting rate of subsequent surgery in CSDH patients managed with corticosteroids. RESULTS: A total of 532 CSDH patients were identified. Subsequently, a total of 364 patients who were managed conservatively were included for further analysis. The majority (315 patients; 59.1%) were managed conservatively. Forty-nine patients (9.2%) received steroids as first-line treatment. There was considerable variation in steroid dosing regimens, with the commonest involving 4 mg dexamethasone three times daily for 5 days. Four patients in the steroid group required subsequent surgery (8.2%), compared with 22 conservatively managed patients (7.0%). Statistical analysis revealed no significant difference in the rate of surgery (chi-square 0.089, difference 1, P = 0.77). CONCLUSIONS: Current evidence implicates a potentially beneficial role of dexamethasone in the management of CSDH. However, it remains unclear whether the rate of crossover to surgery is reduced in patients treated with corticosteroids compared with those managed conservatively. A longer duration of study with detailed analysis of individual cases and appropriately randomized cohorts are necessary to draw more reliable conclusions.

Fronto-orbital advancement and reconstruction using reverse frontal bone graft without the use of orbital bar: a technical note.

INTRODUCTION: We describe our technique of using reverse frontal bone graft for FOAR for patients with metopic or coronal synostosis and present our complications using the Leeds classification system for complications in craniosynostosis surgery. METHODS: Since April 2015, seventeen patients have been operated using this technique. We perform a frontal bone graft that is then reversed, and supraorbital margins are drilled out. The orbital bar is then removed and drilled down to make bone dust and on-lay bone grafts which are then used to fill gaps on exposed dura and fill in around the temporal region. RESULTS: All 17 patients who underwent this technique have good cosmetic results. We report 5 (29%) complications and 8 (47%) blood transfusions (7 exposures, 1 cell salvage).

Unexplained paraparesis following subarachnoid haemorrhage.

Spinal arachnoid cysts (SAC) are rare in isolation and the exact aetiology is still debated. Primary (congenital) cysts are caused by structural abnormalities in the arachnoid layer and largely affect the thoracic region. Secondary cysts are induced by a multitude of factors, infection, trauma or iatrogenic response, and can affect any level of the spinal cord. While subarachnoid haemorrhage (SAH) is a relatively common condition with significant repercussions, it is extremely uncommonly associated with SAC. When present, it may develop in the months and years after the original bleed, giving rise to new neurological symptoms. Prompt treatment is needed to halt or reverse the worsening of symptoms and questions are still being asked about how best to approach this condition. A 42-year-old man presented with chronic back pain, severe worsening ataxia and numbness below the umbilicus, 7 months after treatment for a World Federation of Neurosurgical Societies grade five (WFNS V) SAH. Imaging revealed a SAC extending from T12 to L4 and causing thecal compression. This was treated with a L3 laminectomy andmarsupialisation. An improvement in neurological function was observed at 6 months. Aetiology of the SAC and its association with SAH are discussed and a review of the relevant literature is provided.

Cavernous sinus meningioma presenting as third nerve palsy in pregnancy.

A 33-year-old female patient presented with diplopia and left eye ptosis 26 weeks into her first pregnancy. No investigation was conducted at the time and her symptoms subsided 4 weeks post partum. This same phenomenon occurred during second pregnancy at 20 weeks of gestation, with patient becoming symptom-free again 6 weeks after giving birth. MRI revealed a lesion in the left cavernous sinus in keeping with a meningioma. Due to the surgically challenging location, the lesion was treated with gamma knife radiosurgery. To date, the patient remains asymptomatic with no progression on follow-up imaging 9 years on.

Recurrent hiccups may signal brainstem pathology and should be investigated.

While occasional hiccups are normal, their persistent recurrence is distressing and may have an underlying aetiology. Patients with recurrent hiccups may undergo a long journey and see many physicians before the diagnosis is finally made. The purpose of this report is to increase awareness of central nervous system lesions as a possible cause for recurrent hiccups and provide an illustrative case of an otherwise fit man presenting with ongoing hiccups caused by a medullary haemangioblastoma.

Cervical spinal glioblastoma multiforme in the elderly.

Spinal glioblastoma multiforme (GBM) is uncommon, and its diagnosis may be challenging. This is especially true in the elderly population. Best management strategy remains to be defined. The purpose of this report is to document this rare condition, increase awareness (as a potential differential diagnosis) and propose treatment options in the elderly; a review of the relevant literature is included. A biopsy may be beneficial in given circumstances as cervical spinal GBM carries a better prognosis compared with intramedullary metastasis.

A proposal for a new classification of complications in craniosynostosis surgery.

OBJECTIVE Complications have been used extensively to facilitate evaluation of craniosynostosis practice. However, description of complications tends to be nonstandardized, making comparison difficult. The authors propose a new pragmatic classification of complications that relies on prospective data collection, is geared to capture significant morbidity as well as any "near misses" in a systematic fashion, and can be used as a quality improvement tool. METHODS Data on complications for all patients undergoing surgery for nonsyndromic craniosynostosis between 2010 and 2015 were collected from a prospective craniofacial audit database maintained at the authors' institution. Information on comorbidities, details of surgery, and follow-up was extracted from medical records, anesthetic and operation charts, and electronic databases. Complications were defined as any unexpected event that resulted or could have resulted in a temporary or permanent damage to the child. RESULTS A total of 108 operations for the treatment of nonsyndromic craniosynostosis were performed in 103 patients during the 5-year study period. Complications were divided into 6 types: 0) perioperative occurrences; 1) inpatient complications; 2) outpatient complications not requiring readmission; 3) complications requiring readmission; 4) unexpected long-term deficit; and 5) mortality. These types were further subdivided according to the length of stay and time after discharge. The overall complication rate was found to be 35.9%. CONCLUSIONS The proportion of children with some sort of complication using the proposed definition was much higher than commonly reported, predominantly due to the inclusion of problems often dismissed as minor. The authors believe that these complications should be included in determining complication rates, as they will cause distress to families and may point to potential areas for improving a surgical service.

Can patients with a CSF shunt SCUBA dive?

BACKGROUND: Shunt placement for cerebrospinal fluid (CSF) diversion is one of the most commonly performed procedures in neurosurgery. Pleasure or sports diving is a popular sport enjoyed by millions. At present, no guidelines exist to affirm the safety of diving in the presence of a CSF shunt. METHODS: Literature search and review of medical fitness regulations used by diving organisations. RESULTS: Although the available evidence is anecdotal, no reports of shunt-related complications exist and in vitro studies show lasting functionality. CONCLUSIONS: Patients with CSF shunts should undergo careful evaluation including assessment of their cognitive and physical needs as well as co-morbidities. Having a CSF shunt in situ is not in itself a contraindication to SCUBA diving.

Monitoring the changing pattern of delivery of paediatric epilepsy surgery in England--an audit of a regional service and examination of national trends.

PURPOSE: The demand for paediatric epilepsy surgery in the UK greatly exceeds the number of operations performed. Hence, Children's Epilepsy Surgery Service (CESS) was commenced in 2012. This study is aimed to characterise the changes in service delivery in the North East of England Paediatric Neuroscience Network and nationally. METHODS: A retrospective cohort study of paediatric epilepsy surgery in Leeds between 2005 and 2012 is presented followed by analysis of British Paediatric Neurosurgical Group (BPNG) data before and after CESS commissioning. RESULTS: During the study period, 42 children underwent epilepsy surgery in Leeds. The commonest aetiologies were neoplasm (33%), focal cortical dysplasia (19%) and mesial temporal sclerosis (19%). Seizure outcome was 71 % EngelI and 83% EngelI+II. Complications included one infection (2%), two temporary (5%) and one permanent (2%) motor deficits, three new/worsened visual field deficits (7%). There were six re-craniotomies (14%). The BPNG data show a 48% increase in paediatric epilepsy surgery in England between 2009 (90 cases) and 2012 (133 cases), and a 20% fall in 2013 (106 cases)--the first calendar year for CESS. On average, 64% of all operations were performed in London. CONCLUSIONS: The number of children receiving surgery for epilepsy in England had increased annually up to, and declined after, the establishment of CESS centres. The yearly caseload in neurosurgical units outside of London is small. The outcomes from Leeds are comparable to those published elsewhere. Other UK units are encouraged to publish outcomes to facilitate patient, commissioner and provider decision making.

A rare case of anterior sacral meningocoele presenting as cauda equina syndrome.

The authors present a case of anterior sacral meningocoele demonstrating a clinical picture of cauda equina syndrome. To the best of our knowledge, such presentation has not yet been reported.

Repeated citalopram administration counteracts kainic acid-induced spreading of PSA-NCAM-immunoreactive cells and loss of reelin in the adult mouse hippocampus.

Systemic or intracerebral administration of kainic acid in rodents induces neuronal death followed by a cascade of neuroplastic changes in the hippocampus. Kainic acid-induced neuroplasticity is evidenced by alterations in hippocampal neurogenesis, dispersion of the granule cell layer and re-organisation of mossy fibres. Similar abnormalities are observed in patients with temporal lobe epilepsy and, therefore, kainic acid-induced hippocampal neuroplasticity might mimic pathological mechanisms leading to the formation of 'epileptic brain' in patients with temporal lobe epilepsy. Previous studies have demonstrated that selective serotonin re-uptake inhibitor antidepressants might reduce the severity of seizures in epileptic patients and reduce neuronal death in laboratory animal models of kainic acid-induced neurotoxicity. In the present study, we investigated whether kainic acid-induced neuroplasticity in mice is modulated by the repeated administration of citalopram, a selective serotonin reuptake inhibitor. We found that at the histopathological level, repeated citalopram treatment counteracted the kainic acid-induced neuronal loss and dispersion of young granule neurons expressing the polysialylated neural cell adhesion molecule within the granule cell layer of the hippocampus. Citalopram also counteracted the downregulation of reelin on both mRNA and protein levels induced by kainic acid administration. Our findings indicate that repeated administration of citalopram is able to prevent kainic acid-induced abnormal brain plasticity and thereby prevent the formation of an epileptic phenotype.