Comparison between outcomes of endovascular and surgical treatments of ruptured anterior communicating artery aneurysms.

INTRODUCTION: The natural history and optimal treatment of previously ruptured anterior communicating artery (ACOM) aneurysms that recur is unknown. This study looks at rates of complications and recurrences of ruptured ACOM aneurysms treated endovascularly and surgically. MATERIALS AND METHODS: A retrospective observational study of all patients presenting to a single tertiary neurosurgical centre with the first presentation of subarachnoid haemorrhage (SAH) secondary to a ruptured ACOM aneurysm. Data was collected from November 2012 to September 2018 and included baseline demographics, aneurysm characteristics, management, complications, follow-up imaging, and clinical outcomes. RESULTS: 137 patients were included in the study. 113 aneurysms were coiled and 19 were clipped. Management decisions were taken by the multidisciplinary team based on aneurysm morphology or the presence of a haematoma exerting mass effect. There were 187.5 patient-years of follow-up, with a median of 3 years (range 0-73 months). Rates of vasospasm, infarction, CSF diversion, rebleed, length of stay, and functional outcome were not significantly different in the two cohorts. There was a statistically significant increase in the risk of ACOM recurrence in the coiled group when compared to the clipped group at one year (p = .0433). 15 patients required further treatment at a median time of 16 months. In a subgroup group analysis of coiled aneurysms, there was no statistical differences in rates of rebleeding or the functional outcome in those that had aneurysm recurrence and those that did not. CONCLUSIONS: This study suggests patients with aneurysms treated by endovascular coiling have an increased risk of recurrence versus those treated with clipping. However, the risk of rebleed was not statistically significant. The prevention and impact of recurrence and residual aneurysms remains incompletely understood. Hence, treatment decisions should be taken by patients after they have been given carefully considered recommendations from the multi-disciplinary team.

Fusion rates for conservative and surgical management of type II odontoid fractures and its impact.

BACKGROUND: Type II odontoid fractures are known to have low fusion rates following conservative management with a hard collar. However, most patients are elderly with comorbidities and are not fit for surgery. The present study identified the rates of bony fusion, complications, and clinical outcomes following conservative management of type II odontoid fractures. METHODS: We included consecutive patients referred with a suspected odontoid fracture to a Major Trauma Centre in the UK between March 2015 and December 2017. Data including patient demographics, fracture management, complications and outcomes. Bony fusion was assessed by two neurosurgeons and one neuroradiologists. Results were analysed with simple statistics and chi-squared test. RESULTS: 102 patients were included in the study (mean age = 80.4 ± 15.3). 10 (9.8%) were managed surgically and 92 (90.2%) were managed conservatively with a hard collar, for a mean of 87 days. Patients were followed up for a mean of 28.1 months (range 1-855 days) until discharge. 37% developed collar complications, namely pain, stiffness and non-tolerance. Bony union was achieved in 37.3% of patients treated with a hard collar (versus 80% in the surgical group, p = 0.0096). Increasing age was an independent risk factor for non-union (p < 0.001). Of the patients without bony union, none reported symptoms, and 90% were discharged without a collar. CONCLUSION: The management of type II odontoid fractures are difficult in an elderly, co-morbid population. With conservative management fusion rates are low, and collar complications are not insignificant. However, outcomes are good regardless of union.

Lightfield hyperspectral imaging in neuro-oncology surgery: an IDEAL 0 and 1 study.

Introduction: Hyperspectral imaging (HSI) has shown promise in the field of intra-operative imaging and tissue differentiation as it carries the capability to provide real-time information invisible to the naked eye whilst remaining label free. Previous iterations of intra-operative HSI systems have shown limitations, either due to carrying a large footprint limiting ease of use within the confines of a neurosurgical theater environment, having a slow image acquisition time, or by compromising spatial/spectral resolution in favor of improvements to the surgical workflow. Lightfield hyperspectral imaging is a novel technique that has the potential to facilitate video rate image acquisition whilst maintaining a high spectral resolution. Our pre-clinical and first-in-human studies (IDEAL 0 and 1, respectively) demonstrate the necessary steps leading to the first in-vivo use of a real-time lightfield hyperspectral system in neuro-oncology surgery. Methods: A lightfield hyperspectral camera (Cubert Ultris ×50) was integrated in a bespoke imaging system setup so that it could be safely adopted into the open neurosurgical workflow whilst maintaining sterility. Our system allowed the surgeon to capture in-vivo hyperspectral data (155 bands, 350-1,000 nm) at 1.5 Hz. Following successful implementation in a pre-clinical setup (IDEAL 0), our system was evaluated during brain tumor surgery in a single patient to remove a posterior fossa meningioma (IDEAL 1). Feedback from the theater team was analyzed and incorporated in a follow-up design aimed at implementing an IDEAL 2a study. Results: Focusing on our IDEAL 1 study results, hyperspectral information was acquired from the cerebellum and associated meningioma with minimal disruption to the neurosurgical workflow. To the best of our knowledge, this is the first demonstration of HSI acquisition with 100+ spectral bands at a frame rate over 1Hz in surgery. Discussion: This work demonstrated that a lightfield hyperspectral imaging system not only meets the design criteria and specifications outlined in an IDEAL-0 (pre-clinical) study, but also that it can translate into clinical practice as illustrated by a successful first in human study (IDEAL 1). This opens doors for further development and optimisation, given the increasing evidence that hyperspectral imaging can provide live, wide-field, and label-free intra-operative imaging and tissue differentiation.

Delayed periprosthetic collection after cervical disc arthroplasty.

Cervical disc arthroplasty is a treatment option for symptomatic cervical disc disease. There is a paucity of literature on long-term safety outcomes, durability, and device-related failure rates. The M6-C artificial cervical disc is a device with titanium alloy endplates and a complex polymeric centerpiece. To date, trials have exhibited acceptable safety profiles.This case series describes the presentation, management, and pathological findings of a delayed prevertebral periprosthetic mass anterior to the M6-C disc. Four patients at 3 different institutions underwent cervical disc replacement with the M6-C disc. Two to seven years postoperatively, they presented with dysphagia secondary to a compressive mass anterior to the disc. Case notes were reviewed to collect data on symptoms, management, and outcomes. The patients were systemically well and presented with progressive dysphagia. They had imaging findings of a mass anterior to the disc. They underwent a decompressive procedure, with 2 patients undergoing device removal and fusion. In 2 cases, a soft-tissue mass was seen intraoperatively, with frank pus. In 3 cases, Propionibacterium acnes was identified and antibiotic treatment given. Histopathology demonstrated mixed inflammatory infiltrates with foreign body-type granulomas. Postoperatively, the dysphagia resolved.The development of delayed dysphagia in a patient with an M6-C disc should prompt investigation to identify a mass lesion. To the authors' knowledge, this is the first report of delayed infection, or suspected delayed-type hypersensitivity reaction, following M6-C disc implantation. It is important for this to be added to the device safety concerns. Further prospective studies are needed to establish the incidence and the long-term safety and failure rates of the M6-C disc.

Bilateral otoneurological pathology: To operate or not?

OBJECTIVE: To illustrate our experience when managing a complex patient with potentially life-threatening bilateral otological disease facing multisensory compromise including complete loss of audiovestibular function and visual disturbance Clinical presentation: A 67 year old lady, presented with a large left vestibular schwannoma and extensive right cholesteatoma encircling the otic capsule. She underwent translabyrinthine resection of the vestibular schwannoma, resulting in profound sensorineural hearing loss, vestibular hypofunction and corneal scarring following an initial temporary facial palsy. Due to the extent of the disease and good right-sided bone conduction thresholds, the cholesteatoma was managed conservatively utilising a bone-anchored-hearing-aid with regular review by the Skull-Base team. However, following acute deterioration in hearing and disease extension threatening right facial nerve function, the decision was taken for surgical intervention with a view to staged cochlear implantation (CI). INTERVENTION: Our patient underwent right lateral petrousectomy, total osseous labyrinthectomy, and implantation of an intracochlear 'dummy' with blind sac closure of the external auditory canal. Recovery was excellent with no further deterioration in balance and no loss of facial nerve function. CI occurred 3 months post-operatively with good functional outcome. CONCLUSION: We present the management of bilateral complex otoneurological disease with significant risk of multisensory compromise. Size of the left vestibular schwannoma necessitated surgical resection with resultant loss of ipsilateral audiovestibular function. Due to residual right audiovestibular function and the risks of surgery, the extensive right cholesteatoma was managed conservatively until disease progression necessitated surgical intervention. Subsequently it was possible to restore access to open-set speech with a right CI.

Trafficking and processing of bacterial proteins by mammalian cells: Insights from chondroitinase ABC.

BACKGROUND: There is very little reported in the literature about the relationship between modifications of bacterial proteins and their secretion by mammalian cells that synthesize them. We previously reported that the secretion of the bacterial enzyme Chondroitinase ABC by mammalian cells requires the strategic removal of at least three N-glycosylation sites. The aim of this study was to determine if it is possible to enhance the efficacy of the enzyme as a treatment for spinal cord injury by increasing the quantity of enzyme secreted or by altering its cellular location. METHODOLOGY/PRINCIPAL FINDINGS: To determine if the efficiency of enzyme secretion could be further increased, cells were transfected with constructs encoding the gene for chondroitinase ABC modified for expression by mammalian cells; these contained additional modifications of strategic N-glycosylation sites or alternative signal sequences to direct secretion of the enzyme from the cells. We show that while removal of certain specific N-glycosylation sites enhances enzyme secretion, N-glycosylation of at least two other sites, N-856 and N-773, is essential for both production and secretion of active enzyme. Furthermore, we find that the signal sequence directing secretion also influences the quantity of enzyme secreted, and that this varies widely amongst the cell types tested. Last, we find that replacing the 3'UTR on the cDNA encoding Chondroitinase ABC with that of ß-actin is sufficient to target the enzyme to the neuronal growth cone when transfected into neurons. This also enhances neurite outgrowth on an inhibitory substrate. CONCLUSION/SIGNIFICANCE: Some intracellular trafficking pathways are adversely affected by cryptic signals present in the bacterial gene sequence, whilst unexpectedly others are required for efficient secretion of the enzyme. Furthermore, targeting chondroitinase to the neuronal growth cone promotes its ability to increase neurite outgrowth on an inhibitory substrate. These findings are timely in view of the renewed prospects for gene therapy, and of direct relevance to strategies aimed at expressing foreign proteins in mammalian cells, in particular bacterial proteins.

Diagnostics of Tree Diseases Caused by Phytophthora austrocedri Species.

We present methods for the detection and quantification of four Phytophthora species which are pathogenic on trees; Phytophthora ramorum, Phytophthora kernoviae, Phytophthora lateralis, and Phytophthora austrocedri. Nucleic acid extraction methods are presented for phloem tissue from trees, soil, and pure cultures on agar plates. Real-time PCR methods are presented and include primer and probe sets for each species, general advice on real-time PCR setup and data analysis. A method for sequence-based identification, useful for pure cultures, is also included.